Ulrich Bogdahn

Bio: Ulrich Bogdahn is an academic researcher from University of Regensburg. The author has contributed to research in topics: Neural stem cell & Neurogenesis. The author has an hindex of 67, co-authored 344 publications receiving 32279 citations. Previous affiliations of Ulrich Bogdahn include Hoffmann-La Roche & Volkswagen Foundation.

The effect of transforming growth factor-beta 2-specific phosphorothioate-anti-sense oligodeoxynucleotides in reversing cellular immunosuppression in malignant glioma.

Abstract: This in vitro study was aimed at restitution of transforming growth factor (TGF)-beta 2-mediated suppression of T-lymphocyte activation within malignant gliomas. In early-passage tumor cell cultures of two glioblastomas (HTZ-153 and HTZ-209) and one malignant astrocytoma classified as World Health Organization Grade III (HTZ-243), autologous peripheral blood mononuclear cells were activated by interleukin-1 alpha and interleukin-2 in vitro (lymphokine-activated killer cells) and tested for cytotoxic and proliferative activity. In expression studies (Western blot and Northern hybridization) of all three tumors, TGF-beta could be detected at the protein and messenger ribonucleic acid (mRNA) levels. A polyclonal anti-TGF-beta neutralizing antibody did not enhance lymphocyte proliferation upon stimulation with tumor targets (3H-thymidine incorporation) and slightly stimulated lymphocyte cytotoxicity against autologous target cells. Preincubation of target cells for 12 hours with TGF-beta 2-specific phosphorothioate-anti-sense oligodeoxynucleotides (S-ODN's) did, however, enhance lymphocyte proliferation up to 2.5-fold and autologous tumor cytotoxicity up to 60%, compared to controls not treated with S-ODN's. Incubation of tumor cells with TGF-beta 2-specific S-ODN's resulted in decreased TGF-beta-specific immunoreactivity in cultured glioma cells, in reduced TGF-beta 2 protein concentration (Western blot), and in a change in the expression pattern of TGF-beta 2 mRNA's. These observations may have implications for in vivo and in vitro activation of a cellular immune response against autologous malignant glioma cells.

Mesenchymal Stem Cells Instruct Oligodendrogenic Fate Decision on Adult Neural Stem Cells

Abstract: Adult stem cells reside in different tissues and organs of the adult organism. Among these cells are MSCs that are located in the adult bone marrow and NSCs that exist in the adult central nervous system (CNS). In transplantation experiments, MSCs demonstrated neuroprotective and neuroregenerative effects that were associated with functional improvements. The underlying mechanisms are largely unidentified. Here, we reveal that the interactions between adult MSCs and NSCs, mediated by soluble factors, induce oligodendrogenic fate decision in NSCs at the expense of astrogenesis. This was demonstrated (a) by an increase in the percentage of cells expressing the oligodendrocyte markers GalC and myelin basic protein, (b) by a reduction in the percentage of glial fibrillary acidic protein (GFAP)-expressing cells, and (c) by the expression pattern of cell fate determinants specific for oligodendrogenic differentiation. Thus, it involved enhanced expression of the oligodendrogenic transcription factors Olig1, Olig2, and Nkx2.2 and diminished expression of Id2, an inhibitor of oligodendrogenic differentiation. Results of (a) 5-bromo-2'-deoxyuridine pulse-labeling of cells, (b) cell fate analysis, and (c) cell death/survival analysis suggested an inductive mechanism and excluded a selection process. A candidate factor screen excluded a number of growth factors, cytokines, and neurotrophins that have previously been shown to influence neurogenesis and neural differentiation from the oligodendrogenic activity derived from the MSCs. This work might have major implications for the development of future transplantation strategies for the treatment of degenerative diseases in the CNS.

Contrast-enhanced transcranial color-coded real-time sonography. Results of a phase-two study.

Abstract: Transcranial color-coded real-time sonography has been developed as a promising new bedside procedure to monitor central nervous system parenchymal and vascular pathology; the present study was designed to investigate the potential role of galactose microparticles (SH U 508 A) as a new ultrasound contrast-enhancing agent for transcranial sonography. Ten patients (four women and six men, 24-63 years of age) with a broad spectrum of central nervous system pathology were investigated by transcranial color-coded real-time sonography in a phase-two clinical study. After conventional ultrasound examination, all patients received a maximum of six injections of 10 ml with 200, 300, or 400 mg/mL SH U 508 A. The intracranial vessels were scanned by color flow imaging in the axial and coronal planes through a transtemporal acoustic bone window; in addition, the vertebrobasilar system was followed through the foramen magnum. SH U 508 A was well tolerated without side effects. In axial and coronal scans, the application of SH U 508 A resulted in detection of peripheral branches of the anterior, middle, and posterior cerebral arteries, as well as the posterior communicating and superior cerebellar arteries. In addition, the deep cerebral veins (i.e., inferior sagittal sinus, internal cerebral veins, great cerebral vein of Galen, straight sinus, and the confluence sinuum) were revealed. The transforaminal approach led to detection of the main infratentorial branches (anterior inferior, posterior inferior, and superior cerebellar arteries). One patient could not be insonated without contrast, but after SH U 508 A the trunks of the large intracranial arteries were detected. No obvious changes in the ultrasound pattern of the central nervous system parenchyma were observed. These preliminary data indicate that the use of a transpulmonary ultrasound contrast agent (SH U 508 A) may substantially broaden the spectrum and potential diagnostic utility of transcranial ultrasound by allowing detection of supratentorial peripheral central nervous system arteries, deep cerebral veins, and (through the foramen magnum) the entire vertebrobasilar system, including the cerebellar arteries.

CD133 Expression and Cancer Stem Cells Predict Prognosis in High‐grade Oligodendroglial Tumors

Abstract: High-grade oligodendroglial tumors, that is, anaplastic oligodendroglial tumors and glioblastomas with oligodendroglial component, differ significantly in terms of prognosis and response to chemotherapy. Differentiation might be difficult because the histological differences are vague and reliable markers are not established. We correlated the presence of putative cancer stem cells (CSC) in high-grade oligodendroglial tumors (WHO grades III and IV) with clinical outcome. Tumors with favorable prognosis neither contained CSC nor did they show CD133 expression. Tumor cells resembled lineage-restricted progenitor cells with limited proliferative capacity and differentiation profile. In contrast, CD133 expression and stem cell-like tumor cells characterized tumors with poor prognosis. They showed neurosphere-like growth, differentiated into cells of all neural lineages, and were tumorigenic in nude mice. In our series, CSC and expression of CD133 predicted the clinical course of disease better than the histological grading. To confirm these results, we retrospectively analyzed 36 high-grade oligodendroglial tumors. Again, CD133 expression indicated shorter survival and predicted clinical outcome more reliable than the histological assessment. Our data show that detection of CSC and expression of CD133 is predictive of prognosis in high-grade oligodendroglial tumors. The presence or absence of CD133(+) CSC might explain the crucial biological difference between WHO grade III and IV oligodendroglial tumors.

Guidelines for the Early Management of Patients With Acute Ischemic Stroke A Guideline for Healthcare Professionals From the American Heart Association/American Stroke Association

Abstract: Background and Purpose—The authors present an overview of the current evidence and management recommendations for evaluation and treatment of adults with acute ischemic stroke. The intended audienc...

Headache Classification Committee of the International Headache Society (IHS) The International Classification of Headache Disorders, 3rd edition

Abstract: The 3rd edition of the International Classification of Headache Disorders (ICHD-3) may be reproduced freely for scientific, educational or clinical uses by institutions, societies or individuals. Otherwise, copyright belongs exclusively to the International Headache Society. Reproduction of any part or parts in any manner for commercial uses requires the Society’s permission, which will be granted on payment of a fee. Please contact the publisher at the address below. International Headache Society 2013–2018. Applications for copyright permissions should be submitted to Sage Publications Ltd, 1 Oliver’s Yard, 55 City Road, London EC1Y 1SP, United Kingdom (tel: þ44 (0) 207 324 8500; fax: þ44 (0) 207 324 8600; permissions@sagepub.co.uk) (www.uk.sagepub.com). Translations

Effects of radiotherapy with concomitant and adjuvant temozolomide versus radiotherapy alone on survival in glioblastoma in a randomised phase III study: 5-year analysis of the EORTC-NCIC trial

Abstract: BACKGROUND: In 2004, a randomised phase III trial by the European Organisation for Research and Treatment of Cancer (EORTC) and National Cancer Institute of Canada Clinical Trials Group (NCIC) reported improved median and 2-year survival for patients with glioblastoma treated with concomitant and adjuvant temozolomide and radiotherapy. We report the final results with a median follow-up of more than 5 years. METHODS: Adult patients with newly diagnosed glioblastoma were randomly assigned to receive either standard radiotherapy or identical radiotherapy with concomitant temozolomide followed by up to six cycles of adjuvant temozolomide. The methylation status of the methyl-guanine methyl transferase gene, MGMT, was determined retrospectively from the tumour tissue of 206 patients. The primary endpoint was overall survival. Analyses were by intention to treat. This trial is registered with Clinicaltrials.gov, number NCT00006353. FINDINGS: Between Aug 17, 2000, and March 22, 2002, 573 patients were assigned to treatment. 278 (97%) of 286 patients in the radiotherapy alone group and 254 (89%) of 287 in the combined-treatment group died during 5 years of follow-up. Overall survival was 27.2% (95% CI 22.2-32.5) at 2 years, 16.0% (12.0-20.6) at 3 years, 12.1% (8.5-16.4) at 4 years, and 9.8% (6.4-14.0) at 5 years with temozolomide, versus 10.9% (7.6-14.8), 4.4% (2.4-7.2), 3.0% (1.4-5.7), and 1.9% (0.6-4.4) with radiotherapy alone (hazard ratio 0.6, 95% CI 0.5-0.7; p<0.0001). A benefit of combined therapy was recorded in all clinical prognostic subgroups, including patients aged 60-70 years. Methylation of the MGMT promoter was the strongest predictor for outcome and benefit from temozolomide chemotherapy. INTERPRETATION: Benefits of adjuvant temozolomide with radiotherapy lasted throughout 5 years of follow-up. A few patients in favourable prognostic categories survive longer than 5 years. MGMT methylation status identifies patients most likely to benefit from the addition of temozolomide. FUNDING: EORTC, NCIC, Nelia and Amadeo Barletta Foundation, Schering-Plough.

MGMT Gene Silencing and Benefit from Temozolomide in Glioblastoma

Abstract: background Epigenetic silencing of the MGMT (O 6 -methylguanine–DNA methyltransferase) DNArepair gene by promoter methylation compromises DNA repair and has been associated with longer survival in patients with glioblastoma who receive alkylating agents. methods We tested the relationship between MGMT silencing in the tumor and the survival of patients who were enrolled in a randomized trial comparing radiotherapy alone with radiotherapy combined with concomitant and adjuvant treatment with temozolomide. The methylation status of the MGMT promoter was determined by methylation-specific polymerase-chain-reaction analysis. results The MGMT promoter was methylated in 45 percent of 206 assessable cases. Irrespective of treatment, MGMT promoter methylation was an independent favorable prognostic factor (P<0.001 by the log-rank test; hazard ratio, 0.45; 95 percent confidence interval, 0.32 to 0.61). Among patients whose tumor contained a methylated MGMT promoter, a survival benefit was observed in patients treated with temozolomide and radiotherapy; their median survival was 21.7 months (95 percent confidence interval, 17.4 to 30.4), as compared with 15.3 months (95 percent confidence interval, 13.0 to 20.9) among those who were assigned to only radiotherapy (P=0.007 by the log-rank test). In the absence of methylation of the MGMT promoter, there was a smaller and statistically insignificant difference in survival between the treatment groups. conclusions Patients with glioblastoma containing a methylated MGMT promoter benefited from temozolomide, whereas those who did not have a methylated MGMT promoter did not have such a benefit.