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U Bogdahn

Publications and source records attributed to U Bogdahn.

At least 37 records · Page 2Linked to original sources
PubMed2003

"Motor circuit" gray matter changes in idiopathic cervical dystonia.

BACKGROUND: Idiopathic cervical dystonia (ICD), the most common adult-onset focal dystonia, is clinically characterized by involuntary uni- or bilateral contractions of head and neck musculature. One crucial criterion for the diagnosis of ICD is normal results on MRI of the brain. OBJECTIVE: To test the hypothesis whether subtle brain structure changes occur in ICD. METHODS: Using voxel-based morphometry, the authors compared the brain structure of 10 patients with ICD with that of 10 healthy sex- and age-matched controls using high-resolution MRI. RESULTS: Patients with ICD showed an increase in gray matter density bilaterally in the motor cortex and in the cerebellar flocculus and unilaterally in the right globus pallidus internus. In addition, a decrease in gray matter density was observed in the right caudal supplementary motor area as well as in the right dorsal lateral prefrontal and visual cortex. CONCLUSIONS: These results demonstrate for the first time in vivo subtle morphologic alterations in ICD. These data challenge the principal concept that patients with ICD have no brain structure abnormalities and that this movement disorder is solely due to abnormal cerebral function.

Adult↗
PubMed2002

Intractable eye pain: indication for triptans.

Management of pain is difficult in many eye diseases. Particularly in patients undergoing surgical procedures, postoperative intractable pain is a major concern and severely influences the patient's comfort. We present 13 patients (eight male, five female, mean age 36 years) in whom sumatriptan, a highly selective 5-HT1B/1D agonist that is normally used as a specific anti-migraine drug, was used for the treatment of pain following photorefractive keratectomy (PRK). In two patients both eyes were operated on different days, resulting in a total of 15 operated eyes. A positive clinical response was achieved in all patients. In particular, in four patients, who received a second dose prophylactically 4 h following the first dose and before the recurrence of pain, we achieved excellent efficacy and stable control of pain. Further controlled studies are needed to investigate the usefulness of 5-HT1B/1D agonists in painful eye conditions.

Adult↗
PubMed2001

Long-term stabilization in patients with malignant glioma after treatment with liposomal doxorubicin.

BACKGROUND: Resistance to chemotherapeutic agents and poor blood-brain barrier penetration are major limitations in the treatment of malignant glioma. To improve drug delivery across the blood-brain barrier, the authors used doxorubicin as liposomal encapsulated formulation (Caelyx, Scheringh-Plough, Munich, Germany) in therapy of recurrent malignant glioma. METHODS: Fifteen patients with recurrent high-grade gliomas were included in the study. Of these, 13 patients could be evaluated, including 6 patients with glioblastoma, 1 patient with gliosarcoma and 6 patients with anaplastic astrocytoma. The treatment consisted of liposomal doxorubicin (20 mg/m(2)), applied intravenously every 2 weeks. RESULTS: Stabilization of the disease was observed in 54% (7 of 13) of patients. Partial response and complete response (CR) were not observed. Median time-to-progression was 11 weeks. Progression free survival at 12 months was 15%. Median overall survival (OS) after doxorubicin therapy was 40.0 weeks, whereas the median OS after diagnosis reached 20.0 months (87.0 weeks). Doxorubicin was well tolerated, with main side effects being palmoplantar erythrodysesthesia occurring in 38% and myelotoxicity (World Health Organization Grade 3-4) in 31% of the patients. CONCLUSIONS: Doxorubicin has been shown to be a safe treatment with moderate activity that may lead to long-term stabilization in recurrent high-grade glioma patients. Of note, median OS after all and after initiation of recurrence therapy was prolonged in comparison with the OS in other Phase II studies, as recently described by Wong et al. (Wong ET, Hess KR, Gleason MJ, Jaeckle KA, Kyritsis AP, Prados MD, et al. Outcomes and prognostic factors in recurrent glioma patients enrolled onto phase II clinical trials. J Clin Oncol 1999;17:2572.).

Adult↗
PubMed2001

Sonographic parenchymal and brain perfusion imaging: preliminary results in four patients following decompressive surgery for malignant middle cerebral artery infarct.

To investigate new methods of diagnostic transcranial sonography for brain parenchymal, vascular and perfusion imaging, we performed 3-D native tissue harmonic transcranial sonography (3D-nthTCS), 3-D transcranial color-coded duplex sonography (3D-TCCS), and "loss-of-correlation" imaging (LOC-TCCS) in four patients following early hemicraniectomy due to space-occupying "malignant" middle cerebral artery infarction (MMCAI). Three-dimensional datasets, utilizing 3D-nthTCS and 3D-TCCS, were created and up to 10 axial 2-D B-mode image planes, similar to CCT, reconstructed in each patient. Three-dimensional reconstructions of the circle of Willis documented one persistent carotid-T occlusion and three recanalizations of the MCA. LOC-TCCS, based on stimulated acoustic emission from an ultrasound (US) contrast agent, demonstrated a perfusion deficit in 2 of 3 patients, with regard to their infarcts. Concluding, 3D-nthTCS, 3D-TCCS and LOC-TCCS are promising tools for bedside monitoring, early prognosis and treatment evaluation for MMCAI in the postoperative period. Further studies should be performed to standardize these new methods and evaluate their applications through the intact calvarina.

Adult↗
PubMed2001

Echo-enhanced transcranial color-coded US: clinical usefulness of intravenous infusion versus bolus injection of SH U 508A.

Twelve patients with insufficient transcranial Doppler signal underwent transcranial color-coded ultrasonography before and after administration of SH U 508A with different modes of administration. Clinically useful enhancement time after bolus injection was surpassed by that after standard infusion (1 mL/min), whereas further prolongation was observed after individualized infusion. Intravenous infusion of SH U 508A provides a prolonged useful enhancement compared with that after bolus injection.

Contrast Media↗
PubMed2001

Dynamic and three-dimensional transcranial ultrasonography of an arachnoid cyst in the cerebral convexity. Technical note.

Structural imaging of the brain, such as cerebral computerized tomography (CT) and magnetic resonance (MR) imaging, is state-of-the-art. Dynamic transcranial (dTC) ultrasonography and three-dimensional (3D) transcranial color-coded duplex (TCC) ultrasonography are complementary, noninvasive procedures with the capacity for real-time imaging, which may aid in the temporary management of space-occupying lesions. A 16-year-old woman presented with recurrent tension-type headaches. A space-occupying arachnoid cyst in the cerebral convexity was demonstrated on MR images. The patient underwent an examination for raised intracranial pressure. which was performed using a standard color-coded duplex ultrasonography system attached to a personal computer-based system for 3D data acquisition. Transcranial ultrasonography was used to identify the outer arachnoid membrane of the cyst, which undulated freely in response to rotation of the patient's head (headshake maneuver). Three-dimensional data sets were acquired and, using a multiplanar reformatting reconstruction algorithm, the authors obtained high-resolution images that corresponded to the initial MR image and a follow-up cranial CT scan. No detectable differences were observed on dTC or 3D TC ultrasonograms obtained at follow-up examinations performed 9 and 28 months later. Three-dimensional TCC and dTC ultrasonography may complement conventional diagnostic procedures such as MR and CT imaging. This report represents evidence of the high resolution and good reproducibility of 3D TC methods. Ultrasonography is a mobile and inexpensive tool and may be used to improve management and therapeutic strategies for patients with space-occupying brain lesions in selected cases.

Adolescent↗
PubMed2000

[Carotid endarterectomy and carotid stenting. A pilot study of a prospective, randomized and controlled comparison].

INTRODUCTION: A prospective, randomized and controlled trial is conducted to compare carotid endarterectomy and carotid stenting in high grade symptomatic carotid artery stenoses. METHODS: According to the study design symptomatic patients with a angiographically high-grade (> or = 70%) internal carotid artery stenosis are included. Pre- and postinterventional diagnostics during the hospitalization period includes neurological assessment, duplex sonography of the cervical and cerebral arteries and magnetic resonance imaging of the brain. Follow-up examinations are scheduled after 1, 6 and 12 months and consist of a neurological assessment and duplex sonography. After 12 months selective angiography and magnetic resonance imaging of the brain will be performed additionally. During a period of 9 months up to now 23/137 patients treated for a carotid artery stenosis were included in the study, 11 patients underwent surgery and 12 patients carotid stenting. RESULTS: Carotid stenting and endarterectomy was primarily successful without residual stenosis > 30% in each patient without the occurrence of stroke or death. In 18 follow-up examinations (neurological assessment including duplex sonography) of 13 patients (13 follow-up examinations after 30 days, 5 after 6 months) no relevant restenosis and no stroke occurred. CONCLUSION: As of yet, carotid stenting was a safe procedure. Due to the small number of patients a definitive conclusion can not be drawn.

Angiography, Digital Subtraction↗
PubMed2000

Transcranial Doppler ultrasonography: year 2000 update.

In this update, the main clinical applications of transcranial Doppler ultrasonography are reassessed. A specific format for technology assessment, personal experience, and an extensive review of the literature form the basis of the evaluation. The document is approved by the American Society of Neuroimaging and the Neurosonology Research Group of the World Federation of Neurology.

Brain Diseases↗
PubMed1999

Somatostatin receptor scintigraphy in thymoma imaging method and clinical application.

Somatostatin receptor scintigraphy with 111In-[DTPA-D-Phe1]-octreotide has the potential for visualizing primary and recurrent thymomas in patients with myasthenia gravis, whereas thymic hyperplasias fail to accumulate somatostatin analog peptides. We demonstrate somatostatin receptor imaging findings in a patient with a mixed encapsulated thymoma which exhibited intense 111In-[DTPA-D-Phe1]-octreotide uptake in early and late scans. In another patient with a history of malignant thymoma 111In-[DTPA-D-Phe1]-octreotide accumulation was clearly seen in a mass suspected to be a recurrence. This paper describes the imaging protocol including Single Photon Emission Computed Tomography (SPECT) and discusses the clinical applications of this feasible functional imaging method in patients with thymomas.

Female↗
PubMed1998

[3-dimensional echo-enhanced transcranial Doppler ultrasound diagnosis].

Echo-enhancing agents improve the signal intensity of transcranial Doppler signals, enabling a novel approach of three-dimensional transcranial vascular imaging by Doppler ultrasound. The basic principle, system requirements and early clinical results with a custom built system are described. Transcranial color Doppler imaging was performed through the temporal bone acoustic window. During i.v. administration of the transpulmonary stable, galactose-based echo-enhancer Levovist (Schering) the video output of the ultrasound scanner was digitized and the spatial position of the recorded frames was simultaneously registered using a mechanical position sensor. After automatic segmentation of the color information, the 3D datasets were reconstructed offline using a Unix-based workstation (Silicon Graphics). Visualization was achieved by maximum intensity projection or surface visualization techniques. Administration of Levovist resulted in good enhancement of the vascular Doppler signal intensity, enabling acquisition of a 3D dataset of the complete circle of Willis with an imaging window of approximately 3-5 min for one i.v. injection. The vascularity of tumors could be recorded as a 3D dataset and further analyzed. The power Doppler technique with echoenhancement proved a valuable tool for 3D dataset recording. 3D datasets clearly facilitated the diagnosis of the vascular anatomy and lesion vascularity and provided additional information on localization of feeders, vascular displacement and extent of tumor vascularity.

Blood Flow Velocity↗
PubMed1998

Chronic inflammatory demyelinating polyradiculoneuropathy: superiority of protein A immunoadsorption over plasma exchange treatment.

We present a patient with chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) who was treated regularly with plasma exchanges (PE) because response to other therapies including i.v. immunoglobulins was not adequate. To reduce nonspecific protein losses due to repeated PE and increase IgG-removal, immunoadsorption (i.a.)-therapy using sepharose-bound protein A was initiated. Retrospective analysis of clinical data including muscle strength and walking distance shows that IA led to more rapid and greater functional improvement than PE in this patient with no relevant side effects. After 3 years of therapy lymphoma was diagnosed and treated. The patient had no relapses of CIDP for 17 months, when his functional status deteriorated again necessitating further IA-therapy. It is concluded that IgG removal by IA in CIDP is more effective and has fewer complications than PE. Due to the chronic course of CIDP requiring repeated interventions IA is also not more expensive than PE.

Chronic Disease↗
PubMed1997

Transcranial duplex ultrasound: experience with contrast enhancing agents.

Transcranial duplex real time sonography (TCCS) is a non-invasive imaging modality that allows repetitive examinations of central nervous system vascular and parenchymal anatomy; a broad spectrum of cerebral pathology may be disclosed: vascular changes include ischemic and hemorrhagic stroke, arteriosclerotic vascular degeneration, arteno-venous malformations and aneurysms, as well as neoplastic and degenerative parenchymal disorders. Imaging was performed with a duplex ultrasound system, employing a 2.25 resp. 2.0 MHz phased-array transducer. Imaging was achieved through the acoustic bone window of the temporal bone and through the foramen magnum. For three-dimensional image reconstruction a mechanical position sensor and online video grabbing was applied. To evaluate the potential of a transpulmonary stable ultrasound contrast enhancing agent we used galactose-based SH U 508 A (Levovist, Schering, Berlin) with 1 to 6 i.v. injections per patient in a phase 2/3 clinical protocol. The signal to noise ratio is significantly improved; the Doppler signal intensity is increased by approx. 25 dB. Levovist was well tolerated and no adverse events occurred, approx. 30% of patients had a sensation of heat and slight pain at the injection site during and shortly after the injection. With the increase in signal intensity, the complete circle of Willis, the peripheral arterial branches, the vertebro-basilar system and the basal venous system may be depicted. In addition, tumour parenchyma vascularisation may be detected, as well as improved delineation of arteriovenous malformations and aneurysms. Three dimensional image reconstruction may represent a novel option in contrast enhanced transcranial duplex imaging including additional information about 3D structure and continuity.

Adolescent↗
PubMed1996

Transforming growth factor-beta-mediated autocrine growth regulation of gliomas as detected with phosphorothioate antisense oligonucleotides.

Transforming growth factors-beta 1 and -beta 2 (TGF-beta 1 and -beta 2) are important growth-regulatory proteins for astroglial neoplasms. We analyzed their role in tumor-cell proliferation in 12 glioma cell lines, employing phosphorothioate antisense oligodeoxynucleotides (S-ODNs, 14 mer), specifically targeted against the coding sequences of TGF-beta 1-mRNA and TGF-beta 2-mRNA. TGF-beta 1-S-ODNs inhibited cell proliferation in 5 of 12 gliomas, whereas TGF-beta 2-S-ODNs reduced the cell proliferation in all glioma cell lines, compared to nonsense-S-ODN-treated and S-ODN-untreated cells as controls. The efficacy and specificity of antisense effects was validated by Northern-blot analysis and determination of protein concentrations in culture supernatants (ELISA). Exogenous hrTGF-beta 1 either stimulated or inhibited the cell lines, whereas pnTGF-beta 2 stimulated the proliferation of most glioma cells. Blocking the extracellular pathway of TGF-beta by neutralizing antibodies only slightly inhibited those cell lines, which were markedly stimulated by TGF-betas. As the effects of TGF-beta 2-S-ODNs were much stronger than those of TGF-beta neutralizing antibodies, we postulate that the endogenously produced TGF-beta 2 control glioma-cell proliferation, in part by an intracellular loop.

Base Sequence↗
PubMed1996

Structure and promoter analysis of the gene encoding the human melanoma-inhibiting protein MIA.

We have recently described the isolation of a novel protein, MIA, which is secreted from malignant melanoma cells and elicits growth inhibition on melanoma cells in vitro (Blesch, A., Bosserhoff, A. K., Apfel, R., Behl, C., Hessdörfer, B., Schmitt, A., Jachimczak, P., Lottspeich, F., Schlingensiepen, H., Buettner, R., and Bogdahn, U. (1994) Cancer Res. 54, 5695-5701). Here, we report the structure of the human MIA gene locus, describe its expression pattern in melanocytic tumors in vivo, and provide an initial characterization of the MIA promoter. The MIA gene is encoded by four exons, and the mRNA initiation site was identified 70 base pairs upstream from the translation start codon. MIA mRNA expression in vivo correlated with progressive malignancy of melanocytic lesions and was inducible in other cells by phorbol esters. To investigate mechanisms mediating this melanoma-associated expression pattern, we analyzed the promoter activity of the 1.3-kilobase genomic sequences located 5'-upstream of the MIA gene. The MIA promoter conferred high levels of gene activation specifically in human and murine melanoma cells, and its activity was further enhanced by treatment with phorbol esters. Site-directed mutation of an NF-kB site within the MIA promoter did reduce the basal promoter activity in melanoma cells but did not change significantly enhancement by phorbol esters.

Animals↗