10 results on '"I. Y. Eyüpoglu"'
Search Results
2. Treatment of severe traumatic brain injury in German pediatric intensive care units-a survey of current practice
- Author
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T. M. K. Völkl, Regina Trollmann, H. Huebner, V. Konrad, I. Y. Eyüpoglu, Fabian B. Fahlbusch, J. Zierk, and Adrian P. Regensburger
- Subjects
Male ,medicine.medical_specialty ,Adolescent ,Traumatic brain injury ,Poison control ,Intensive Care Units, Pediatric ,Severity of Illness Index ,03 medical and health sciences ,Young Adult ,0302 clinical medicine ,Intensive care ,Germany ,Surveys and Questionnaires ,Brain Injuries, Traumatic ,Medicine ,Humans ,030212 general & internal medicine ,Child ,Pediatric intensive care unit ,business.industry ,Glasgow Coma Scale ,Infant, Newborn ,Infant ,General Medicine ,medicine.disease ,Hypertonic saline ,Clinical trial ,Treatment Outcome ,Child, Preschool ,Pediatrics, Perinatology and Child Health ,Emergency medicine ,Practice Guidelines as Topic ,Female ,Neurology (clinical) ,Neurosurgery ,business ,030217 neurology & neurosurgery - Abstract
German pediatric guidelines for severe traumatic brain injury (TBI) management expired in 2011. Thus, divergent evidence-based institutional protocols are predominantly being followed. We performed a survey of current Pediatric Intensive Care Unit (PICU) management of isolated severe TBI in Germany to reveal potential varying practices. Seventy German PICUs were invited to join an anonymous online survey from February to May 2017. Twenty-nine participants (41.4%) successfully completed the survey (17 university hospitals and 12 district hospitals). The majority of items were polar (yes/no) or scaled (e.g., never - always). Main topics were imaging, neurosurgery, neuromonitoring, adjuvant therapy, and medication. Severity of TBI was defined via Glasgow Coma Scale. The majority of respondents (93.1%) had internal TBI standards, and patients were mainly administered to interdisciplinary trauma units. The use of advanced neuromonitoring techniques, intracranial hypertension management, and drug treatment differed between PICUs. Routine administration of hypertonic saline in TBI-associated cerebral edema was performed by 3.4%, while it was never an option for 31.0% of the participants. Prophylactic anticonvulsive therapy was restrictively performed. If indicated, the main anticonvulsive drugs used were phenobarbital and levetiracetam. Neuroendocrine follow-up was recommended/performed by 58.6% of the PICUs. This survey provides an overview of the current PICU practices of isolated severe TBI management in Germany and demonstrates a wide instrumental and therapeutical range, revealing an unmet need for the revised national guideline and further (international) clinical trials for the treatment of severe TBI in pediatrics.
- Published
- 2019
3. Targeting xCT-mediated glutamate release normalizes tumor angiogenesis in the brain
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Tina Sehm, MH Schmidt, Eric P. Meyer, Sebastian Schürmann, NE Savaskan, Marco Stampanoni, I Y Eyüpoglu, Eduard Yakubov, Michael Buchfelder, Oliver Friedrich, Marcus Czabanka, Robert Nitsch, Zheng Fan, ND Stankovic, and Thomas Broggini
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Programmed cell death ,biology ,Glutamate secretion ,Angiogenesis ,Knockout mouse ,Glutamate receptor ,biology.protein ,Cancer research ,NMDA receptor ,SLC7A11 ,Intravital microscopy - Abstract
Brain tumors are among the most malignant primary tumors, hallmarked by angiogenesis, neuronal destruction and brain swelling. Inhibition of the glutamate-cystein antiporter xCT (system xc−/SLC7A11) alleviates seizures, neuronal cell death and tumor-associated brain edema. Here we show enhanced tumor vessel growth and increased brain edema in xCT-expressing brain tumors. Furthermore, xCT-mediated glutamate impacts directly on endothelial cells in an N-methyl-D-aspartate receptor (NMDAR) dependent manner with intracellular Ca2+ release. Cerebral intravital microscopy revealed that xCT-driven tumor vessels are functional and display increased permeability. Endothelial-cell-specific NMDAR1 knockout mice (GRINiΔEC) show suppressed endothelial sprouting and vascular density compared to control littermates. In addition, implanted gliomas in GRINiΔEC mice display reduced tumor vessels in contrast to gliomas in wildtype animals. Moreover, therapeutic targeting of xCT in gliomas alleviates tumor angiogenesis to normalized levels comparable to controls. Our data reveal that xCT and its substrate glutamate specifically operate on endothelial cells and promote neoangiogenesis. Thus, targeting xCT expression and glutamate secretion in gliomas provides a novel therapeutic roadmap for normalizing tumor angiogenesis.
- Published
- 2017
4. Definition of Ktrans and FA Thresholds for Better Assessment of Experimental Glioma Using High-field MRI: A Feasibility Study
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Lubos Budinsky, I Y Eyüpoglu, A. Doerfler, Michael Schwarz, P. Pitann, Andreas Hess, and Tobias Engelhorn
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Brain glioma ,Sensitivity and Specificity ,Animal model ,Cell Line, Tumor ,Glioma ,Image Interpretation, Computer-Assisted ,Fractional anisotropy ,medicine ,Animals ,Radiology, Nuclear Medicine and imaging ,Neuroradiology ,medicine.diagnostic_test ,Brain Neoplasms ,business.industry ,Reproducibility of Results ,Magnetic resonance imaging ,Image Enhancement ,medicine.disease ,Rats, Inbred F344 ,Rats ,Tumor Burden ,High field mri ,Diffusion Tensor Imaging ,Feasibility Studies ,Neurology (clinical) ,Nuclear medicine ,business ,Algorithms ,Diffusion MRI - Abstract
To define K(trans) and fractional anisotropy (FA) thresholds in correlation to histology for improved magnetic resonance imaging (MRI) tumor assessment in an animal model of brain glioma.Twelve rats underwent 4.7 T MRI at day 10 after tumor implantation. Anatomical scans (T2, T1 at 8 min after double dose contrast application) as well as dynamic contrast-enhanced (DCE) imaging with calculation of K(trans) and diffusion tensor imaging (DTI) with calculation of FA were performed. T2- and T1-derived tumor volumes were calculated and thresholds for K(trans) and FA were defined for best MRI tumor assessment correlated to histology.Tumor volumes were 159 ± 14 mm(3) (histology), 126 ± 26 mm(3) (T1 with contrast, r=0.76), and 153 ± 12 mm(3) (T2, r=0.84), respectively. K(trans)- and FA-derived tumor volumes were 160 ± 16 mm(3) (for K(trans ≥ 0.04 min(-1), r=0.94), and 159 ± 14 mm(3) (for FA £0.14, r=0.96), respectively.DCE-MRI and DTI with calculation of K(trans) and FA maps allow very precise brain glioma assessment comparable to histology if established thresholds for the given tumor model are used.
- Published
- 2013
5. Meningomyelozele und Hydrozephalus: interdisziplinäres Management
- Author
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I. Y. Eyüpoglu, O. Ganslandt, and R. Trollmann
- Abstract
Der kongenitale Hydrocephalus (kHC) umfasst ein atiologisch breites Spektrum von angeborenen Fehlbildungen sowie erworbenen Lasionen und erfordert angesichts der Akuitat und Schwere des Krankheitsbildes ein rasches neurochirurgisches und interdisziplinares Handeln. Obwohl die entwicklungsneurologische Prognose entscheidend von der zugrundeliegenden Genese des kHC bestimmt wird, konnte die Mortalitat und Morbiditat von Kindern mit kHC durch Fortschritte der chirurgischen Therapie entscheidend verbessert werden. Mit der endoskopischen Drittventrikulostomie (ETV) steht ein endoskopisches Verfahren mit geringer Komplikationsrate fur ausgewahlte Patienten mit kommunizierendem kHC zur Verfugung. Die Meningomyelocele, der haufigste und klinisch bedeutsamste Neuralrohrdefekt, geht in mehr als 80 % mit einem HC einher. Moderne neurochirurgische und plastisch-chirurgische Techniken zur primaren Deckung der Cele tragen substantiell zur Vermeidung von Komplikationen, insbesondere Infektionen und sekundarer neurologischer Schadigung, bei. Die exakte Diagnose von assoziierten ZNS-Fehlbildungen wie der Chiari-II-Malformation ist Voraussetzung fur die spezifische Therapie und vor allem Pravention von Komplikationen. Der Stellenwert alternativer operativer Behandlungsoptionen wie der pranatalen minimal invasiven chirurgischen Therapie ist derzeit ungeklart. Durch die Etablierung interdisziplinarer ambulanter Betreuungskonzepte kann eine spezialisierte Langzeitbetreuung mit dem Ziel der individuell optimalen Rehabilitation, der Prophylaxe von Komplikationen und psychosozialer Unterstutzung angeboten werden.
- Published
- 2012
6. Stauungspapille und echografisch nachweisbare retroorbitale Erweiterung des Subarachnoidalraums bei offener Fontanelle – Sechs Kasuistiken
- Author
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Gabriele C. Gusek-Schneider, Christian Y. Mardin, I. Y. Eyüpoglu, O. Ganslandt, and R. Trollmann
- Subjects
medicine.medical_specialty ,Consecutive optic atrophy ,business.industry ,Fontanelle ,Age limit ,eye diseases ,Major duodenal papilla ,Ophthalmology ,medicine.anatomical_structure ,medicine ,Radiology ,medicine.symptom ,Papilledema ,business - Abstract
This paper analyses the case reports for three children in which a papilledema occurred before the age of one year. Furthermore, an analysis is also given of three further case reports for children aged less than one year in which, in spite of open fontanelle, no papilledema was found, however, a dilatation of the sub-arachnoidal space was demonstrated echographically. Even in children less than one year of age in which an open fontanelle still exists and in whom a neuro-paediatric clarification of internal hydrocepalus is made, in spite of opththalmoscopically inconspicuous findings for the papilla an echography is indispensable for the evaluation of the sub-arachnoidal space. Here, the early recognition of a dilatation of the retro-bulbar sub-arachnoidal space can possibly prevent the occurrence of a consecutive optic atrophy. At the present time, the data available do not allow the recommendation of an upper age limit for an echographic examination.
- Published
- 2011
7. Dissection of mitogenic and neurodegenerative actions of cystine and glutamate in malignant gliomas
- Author
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Jan Hauke, Christian Tränkle, Eric Hahnen, Sebastian Seufert, I Y Eyüpoglu, and Nic E. Savaskan
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Cancer Research ,Excitotoxicity ,Down-Regulation ,Glutamic Acid ,Cell Growth Processes ,AMPA receptor ,Biology ,Transfection ,medicine.disease_cause ,Mice ,Cell Line, Tumor ,Glioma ,Genetics ,medicine ,Animals ,Humans ,Receptors, AMPA ,Autocrine signalling ,Molecular Biology ,Tumor microenvironment ,Glutamate secretion ,Brain Neoplasms ,Glutamate receptor ,Glutamic acid ,medicine.disease ,Rats ,Biochemistry ,Cancer research ,Cystine ,Signal Transduction - Abstract
Malignant glioma represents one of the most aggressive and lethal human neoplasias. A hallmark of gliomas is their rapid proliferation and destruction of vital brain tissue, a process in which excessive glutamate release by glioma cells takes center stage. Pharmacologic antagonism with glutamate signaling through ionotropic glutamate receptors attenuates glioma progression in vivo, indicating that glutamate release by glioma cells is a prerequisite for rapid glioma growth. Glutamate has been suggested to promote glioma cell proliferation in an autocrine or paracrine manner, in particular by activation of the (RS)-α-amino-3-hydroxy-5-methylisoxazole-4-propionic acid hydrate (AMPA) subtype of glutamate receptors. Here, we dissect the effects of glutamate secretion on glioma progression. Glioma cells release glutamate through the amino-acid antiporter system X(c)(-), a process that is mechanistically linked with cystine incorporation. We show that disrupting glutamate secretion by interfering with the system X(c)(-) activity attenuates glioma cell proliferation solely cystine dependently, whereas glutamate itself does not augment glioma cell growth in vitro. Neither AMPA receptor agonism nor antagonism affects glioma growth in vitro. On a molecular level, AMPA insensitivity is concordant with a pronounced transcriptional downregulation of AMPA receptor subunits or overexpression of the fully edited GluR2 subunit, both of which block receptor activity. Strikingly, AMPA receptor inhibition in tumor-implanted brain slices resulted in markedly reduced tumor progression associated with alleviated neuronal cell death, suggesting that the ability of glutamate to promote glioma progression strictly requires the tumor microenvironment. Concerning a potential pharmacotherapy, targeting system X(c)(-) activity disrupts two major pathophysiological properties of glioma cells, that is, the induction of excitotoxic neuronal cell death and incorporation of cystine required for rapid proliferation.
- Published
- 2010
8. MIF-CD74 signaling impedes microglial M1 polarization and facilitates brain tumorigenesis
- Author
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Michael Schwarz, R Bucala, Eduard Yakubov, A. Doerfler, I Y Eyüpoglu, Ali Ghoochani, Michael Buchfelder, Nic E. Savaskan, and Tobias Engelhorn
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0301 basic medicine ,Cancer Research ,Small interfering RNA ,medicine.medical_treatment ,Biology ,Models, Biological ,03 medical and health sciences ,Interferon-gamma ,Mice ,Growth factor receptor ,Phagocytosis ,Interferon ,Glioma ,Cell Line, Tumor ,Genetics ,medicine ,Animals ,Humans ,Molecular Biology ,Macrophage Migration-Inhibitory Factors ,Microglia ,Histocompatibility Antigens Class II ,medicine.disease ,Cell biology ,Rats ,Antigens, Differentiation, B-Lymphocyte ,Autocrine Communication ,Disease Models, Animal ,030104 developmental biology ,medicine.anatomical_structure ,Cytokine ,Cell Transformation, Neoplastic ,Gene Knockdown Techniques ,Disease Progression ,Heterografts ,Macrophage migration inhibitory factor ,Signal transduction ,medicine.drug ,Signal Transduction - Abstract
Microglial cells in the brain tumor microenvironment are associated with enhanced glioma malignancy. They persist in an immunosuppressive M2 state at the peritumoral site and promote the growth of gliomas. Here, we investigated the underlying factors contributing to the abolished immune surveillance. We show that brain tumors escape pro-inflammatory M1 conversion of microglia via CD74 activation through the secretion of the cytokine macrophage migration inhibitory factor (MIF), which results in a M2 shift of microglial cells. Interruption of this glioma-microglial interaction through an antibody-neutralizing approach or small interfering RNA (siRNA)-mediated inhibition prolongs survival time in glioma-implanted mice by reinstating the microglial pro-inflammatory M1 function. We show that MIF-CD74 signaling inhibits interferon (IFN)-γ secretion in microglia through phosphorylation of microglial ERK1/2 (extracellular signal-regulated protein kinases 1 and 2). The inhibition of MIF signaling or its receptor CD74 promotes IFN-γ release and amplifies tumor death either through pharmacological inhibition or through siRNA-mediated knockdown. The reinstated IFN-γ secretion leads both to direct inhibition of glioma growth as well as inducing a M2 to M1 shift in glioma-associated microglia. Our data reveal that interference with the MIF signaling pathway represents a viable therapeutic option for the restoration of IFN-γ-driven immune surveillance.
- Published
- 2015
9. [Papilledema and echographically detectable retro-orbital dilatation of the sub-arachnoidal space with open fontanelle - six case reports]
- Author
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G C, Gusek-Schneider, C Y, Mardin, R, Trollmann, I Y, Eyüpoglu, and O, Ganslandt
- Subjects
Echocardiography ,Cranial Fontanelles ,Humans ,Infant ,Subarachnoid Space ,Dilatation, Pathologic ,Papilledema - Abstract
This paper analyses the case reports for three children in which a papilledema occurred before the age of one year. Furthermore, an analysis is also given of three further case reports for children aged less than one year in which, in spite of open fontanelle, no papilledema was found, however, a dilatation of the sub-arachnoidal space was demonstrated echographically. Even in children less than one year of age in which an open fontanelle still exists and in whom a neuro-paediatric clarification of internal hydrocepalus is made, in spite of opththalmoscopically inconspicuous findings for the papilla an echography is indispensable for the evaluation of the sub-arachnoidal space. Here, the early recognition of a dilatation of the retro-bulbar sub-arachnoidal space can possibly prevent the occurrence of a consecutive optic atrophy. At the present time, the data available do not allow the recommendation of an upper age limit for an echographic examination.
- Published
- 2011
10. Phagocytosis of neuronal or glial debris by microglial cells: upregulation of MHC class II expression and multinuclear giant cell formation in vitro
- Author
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M, Beyer, U, Gimsa, I Y, Eyüpoglu, N P, Hailer, and R, Nitsch
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Neurons ,Animals, Newborn ,Gene Expression Regulation ,Genes, MHC Class II ,Animals ,Microglia ,Rats, Wistar ,Giant Cells ,Neuroglia ,Cells, Cultured ,Rats ,Up-Regulation - Abstract
Most CNS pathologies are accompanied by the occurrence of activated, phagocytic microglial cells. We intended to investigate whether (1) isolated microglial cells removed from the CNS cytokine network sustain their capacity to acquire an activated phenotype when challenged with cellular or noncellular debris; and (2) different substrates lead to different patterns of microglial activation. It was observed that although removed from their usual surroundings microglial cells preserve their ability to transform to an amoeboid morphology, form multinucleated giant cells, and enhance their expression of MHC class II when exposed to membranes of neuronal or glial origin. Furthermore, cellular substrates derived from primary hippocampal neuronal cultures, neuroblastic cells (B50), or glial cells were all able to induce similar morphological changes and enhanced expression of MHC class II. In contrast, phagocytosis of Latex beads induced an amoeboid morphology but no increase in the expression of immunologically relevant molecules. Interferon-beta (IFN-beta), a substance clinically used in the treatment of the relapsing-remitting form of multiple sclerosis, was shown to inhibit the phagocytosis-induced upregulation of MHC-class II. In summary, phagocytic microglial cells are independent from the CNS cytokine network in their transition from a resting to an activated phenotype; and different cellular substrates, regardless whether they are of neuronal, glial, or even malignant origin, result in similar morphological and functional changes.
- Published
- 2000
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