Transient oligemia is associated with long-term changes in binding densities of cortical inhibitory GABAA receptors in the rat brain

2009

Recently, we could demonstrate in rats that a short transient oligemic period of only 20-minute duration, induced by systemic hypotension, resulted in a transient decline of spatial memory capacities without any histological damage over a subsequent period of 6 months. In our present study, we checked for more subtle alterations within the highly vulnerable hippocampal CA1 subfield using quantification of neuronal cell density and semi-quantitative analysis of the ischemia-sensitive protein MAP2. Since hippocampal excitatory and inhibitory neurotransmitter receptors are crucially involved in spatial memory processes, quantitative in vitro receptor autoradiography was performed using [(3)H]M…

Eosinophilic Meningitis due toAngiostrongylus cantonensisin Germany

2009

We report a case of eosinophilic meningitis due to Angiostrongylus cantonensis in a patient who returned from Thailand. The presence of a compatible epidemiologic history and eosinophilia in cerebrospinal fluid (CSF) lead to the diagnosis, which was confirmed by detection of specific antibodies. After treatment with albendazole and corticosteroids he recovered completely.

Systemic PaO2 oscillations cause mild brain injury in a pig model

2016

OBJECTIVE: Systemic PaO2 oscillations occur during cyclic recruitment and derecruitment of atelectasis in acute respiratory failure and might harm brain tissue integrity. DESIGN: Controlled animal study. SETTING: University research laboratory. SUBJECTS: Adult anesthetized pigs. INTERVENTIONS: Pigs were randomized to a control group (anesthesia and extracorporeal circulation for 20 hr with constant PaO2, n = 10) or an oscillation group (anesthesia and extracorporeal circulation for 20 hr with artificial PaO2 oscillations [3 cycles min⁻¹], n = 10). Five additional animals served as native group (n = 5). MEASUREMENTS AND MAIN RESULTS: Outcome following exposure to artificial PaO2 oscillations…

Revised Definition of Neuropathic Pain and Its Grading System: An Open Case Series Illustrating Its Use in Clinical Practice

2009

The definition of neuropathic pain has recently been revised by an expert committee of the Neuropathic Pain Special Interest Group of the International Association for the Study of Pain (NeuPSIG) as "pain arising as direct consequence of a lesion or disease affecting the somatosensory system," and a grading system of "definite," "probable," and "possible" neuropathic pain has been introduced. This open case series of 5 outpatients (3 men, 2 women; mean age 48 +/- 12 years) demonstrates how the grading system can be applied, in combination with appropriate confirmatory testing, to diagnosis neuropathic conditions in clinical practice. The proposed grading system includes a dynamic algorithm …

FTY720 reduces post-ischemic brain lymphocyte influx but does not improve outcome in permanent murine cerebral ischemia.

2011

Background The contribution of neuroinflammation and specifically brain lymphocyte invasion is increasingly recognised as a substantial pathophysiological mechanism after stroke. FTY720 is a potent treatment for primary neuroinflammatory diseases by inhibiting lymphocyte circulation and brain immigration. Previous studies using transient focal ischemia models showed a protective effect of FTY720 but did only partially characterize the involved pathways. We tested the neuroprotective properties of FTY720 in permanent and transient cortical ischemia and analyzed the underlying neuroimmunological mechanisms. Methodology/Principal Findings FTY720 treatment resulted in substantial reduction of c…

Evaluation of the apparent diffusion coefficient in patients with recurrent glioblastoma under treatment with bevacizumab with radiographic pseudores…

2017

Abstract Background Response Assessment in Neuro-Oncology Criteria (RANO), are used to asses response to first-line treatment of glioblastoma (GBM). Differentiation between response and pseudoresponse under treatment with Bevacizumab (BVZ) remains challenging. This study evaluates ADC changes in patients with radiographic pseudoresponse under treatment with (BVZ). Methods Patients (n = 40) with recurrent GBM under-treatment with BVZ underwent MRI before, two and four months after treatment with BVZ. In patients with radiological pseudoresponse (n = 11), ADC analyses were performed. Areas with decreasing T1 contrast enhancement (CE) and FLAIR signal decrease were manually selected and compar…

Dietary salt promotes ischemic brain injury and is associated with parenchymal migrasome formation

2018

Sodium chloride promotes vascular fibrosis, arterial hypertension, pro-inflammatory immune cell polarization and endothelial dysfunction, all of which might influence outcomes following stroke. But despite enormous translational relevance, the functional importance of sodium chloride in the pathophysiology of acute ischemic stroke is still unclear. In the current study, we show that high-salt diet leads to significantly worse functional outcomes, increased infarct volumes, and a loss of astrocytes and cortical neurons in acute ischemic stroke. While analyzing the underlying pathologic processes, we identified the migrasome as a novel, sodium chloride-driven pathomechanism in acute ischemic …

Low-Frequency Therapeutic Ultrasound with Varied Duty Cycle: Effects on the Ischemic Brain and the Inner Ear

2009

Sonothrombolysis is a promising modality for acute stroke treatment. In vitro data suggest a duty cycle dependence of sonothrombolytic efficacy of low-frequency applications. The aim of our study was to examine its impact on safety issues in a rat model of middle cerebral artery occlusion. Rats were exposed to transcranial 60-kHz ultrasound with varied duty cycles. To determine effects on the inner ear, the acoustic threshold was determined in additional healthy animals (acoustic evoked potentials). A short duty cycle (20%) resulted in significant adverse effects (ischemic volume, hemorrhage, functional outcome), which was not observed in longer duty cycle (80%). Continuous-wave insonation …

The hematopoietic factor G-CSF is a neuronal ligand that counteracts programmed cell death and drives neurogenesis.

2005

G-CSF is a potent hematopoietic factor that enhances survival and drives differentiation of myeloid lineage cells, resulting in the generation of neutrophilic granulocytes. Here, we show that G-CSF passes the intact blood-brain barrier and reduces infarct volume in 2 different rat models of acute stroke. G-CSF displays strong anti-apoptotic activity in mature neurons and activates multiple cell survival pathways. Both G-CSF and its receptor are widely expressed by neurons in the CNS, and their expression is induced by ischemia, which suggests an autocrine protective signaling mechanism. Surprisingly, the G-CSF receptor was also expressed by adult neural stem cells, and G-CSF induced neurona…

Histology and Infarct Volume Determination in Rodent Models of Stroke

2016

Short-term ischemia usually used for ischemic preconditioning causes loss of dendritic integrity after long-term survival in the gerbil hippocampus

2006

Ischemic preconditioning has been established as a powerful experimental neuroprotective strategy, both after global and focal cerebral ischemia. Little is known, however, about the structural and functional long-term outcome. Therefore, our present study was designed to check for potential subtle alterations in the hippocampus after long-term survival. Gerbils were subjected either to short-term ischemia of 2.5 min duration usually used for ischemic preconditioning (n=8) or to sham operation (n=6) and allowed to survive for 6 weeks. Hippocampi with neuronal densities comparable to those of sham-operated control animals were analyzed for dendritic marker proteins MAP2, MAP1B and synaptopodi…

Neuroprotection and glutamate attenuation by acetylsalicylic acid in temporary but not in permanent cerebral ischemia.

2007

To assess the effects of acetylsalicylic acid (ASA) on glutamate and interleukin-6 (IL-6) release in the striatum of rats suffering from cerebral ischemia, we used the microdialysis technique with probes implanted 2 h prior to stroke onset. A total of 36 rats were randomly assigned to either temporary (90 min, n = 18) or permanent (n = 18) middle cerebral artery occlusion (MCAO). Animals received either a bolus of 40 mg/kg ASA or saline as control 30 min after stroke onset. Permanent MCAO led to large infarct volumes with no differences between treatment with ASA (239.8 ± 4.1 mm3) and saline (230.1 ± 3.9 mm3, p = 0.15). In contrast, ASA therapy in temporary ischemia (87.2 ± 6.2 mm3) reduced…

Different postischemic protein expression of the GABA_{A} receptor α2 subunit and the plasticity-associated protein MAP1B after treatment with BDNF v…

2009

Purpose Recent data indicate that both brain-derived neurotrophic factor (BDNF) and granulocyte-colony stimulating factor (G-CSF) exert substantial neuroregenerative effects and improve functional outcome after ischemic stroke. In the present study, we checked for potential differences in the postischemic modulation of various excitatory and inhibitory neurotransmitter receptors as well as various marker molecules for structural plasticity by BDNF versus G-CSF. Methods Adult male Wistar rats were subjected to photothrombotic ischemia and subsequently treated with NaCl, BDNF or G-CSF, respectively. After 6 weeks, postischemic protein expression of the NR1, GluR1 and alpha2 subunit of the NMD…

Fatigue in SLE: diagnostic and pathogenic impact of anti-N-methyl-D-aspartate receptor (NMDAR) autoantibodies.

2019

ObjectivesWe explored the impact of circulating anti-N-methyl-D-aspartate receptor (NMDAR) antibodies on the severity of fatigue in patients with systemic lupus erythematosus (SLE).MethodsSerum samples of 426 patients with SLE were analysed for the presence of antibodies to the NR2 subunit of the NMDAR. In parallel, the severity of fatigue was determined according to the Fatigue Scale for Motor and Cognitive functions questionnaire. In a subgroup of patients with SLE, the hippocampal volume was correlated with the levels of anti-NR2 antibodies. Isolated immunoglobulin G from patients with anti-NR2 antibodies were used for murine immunohistochemical experiments and functional assays on neuro…

Visualizing cell death in experimental focal cerebral ischemia: promises, problems, and perspectives

2011

One of the hallmarks of stroke pathophysiology is the widespread death of many different types of brain cells. As our understanding of the complex disease that is stroke has grown, it is now generally accepted that various different mechanisms can result in cell damage and eventual death. A plethora of techniques is available to identify various pathological features of cell death in stroke; each has its own drawbacks and pitfalls, and most are unable to distinguish between different types of cell death, which partially explains the widespread misuse of many terms. The purpose of this review is to summarize the standard histopathological and immunohistochemical techniques used to identify …

C2orf69 mutations disrupt mitochondrial function and cause a multisystem human disorder with recurring autoinflammation

2021

BACKGROUND. Deciphering the function of the many genes previously classified as uncharacterized open reading frame (ORF) would complete our understanding of a cell’s function and its pathophysiology. METHODS. Whole-exome sequencing, yeast 2-hybrid and transcriptome analyses, and molecular characterization were performed in this study to uncover the function of the C2orf69 gene. RESULTS. We identified loss-of-function mutations in the uncharacterized C2orf69 gene in 8 individuals with brain abnormalities involving hypomyelination and microcephaly, liver dysfunction, and recurrent autoinflammation. C2orf69 contains an N-terminal signal peptide that is required and sufficient for mitochondrial…

MGMT activity, promoter methylation and immunohistochemistry of pretreatment and recurrent malignant gliomas: a comparative study on astrocytoma and …

2010

The DNA repair protein O(6)-methylguanine-DNA methyltransferase (MGMT) is a key player in tumor cell resistance. Promoter methylation, MGMT activity and immunohistochemistry are used for determining the MGMT status. However, it is unclear whether MGMT promoter methylation correlates with MGMT activity and whether MGMT promoter methylation of the pretreatment tumor predicts the MGMT status of recurrences. To address these questions, we determined MGMT activity promoter methylation and immunoreactivity in pretreatment and recurrent glioblastomas (GB, WHO Grade IV), and in astrocytomas (WHO Grade III). We show that GB that were promoter methylated display a range of 0-62 fmol/mg MGMT and tumor…

Intrahematomal Ultrasound Enhances RtPA-Fibrinolysis in a Porcine Model of Intracerebral Hemorrhage

2021

Catheter-based ultrasound-thrombolysis has been successfully used in a small clinical trial in order to enhance recombinant tissue plasminogen activator (rtPA)-fibrinolysis, for the treatment of spontaneous intracerebral hemorrhages (ICHs). The aim of this study was to investigate the ultra-early effects of ultrasound on hematoma and the surrounding brain tissue in a porcine ICH-model. To achieve this, 21 pigs with a right frontal ICH were randomly assigned to four groups: (1) drainage (n = 3), (2) drainage + rtPA (n = 6), (3) drainage + ultrasound (n = 6), and (4) drainage + ultrasound + rtPA (n = 6). The hematoma volume assessment was performed using cranial MRI before and after the treat…

Immunohistochemical analysis of KCNQ3 potassium channels in mouse brain.

2005

KCNQ-type potassium channels generate the so-called M-current regulating excitability in many neurons. Mutations in KCNQ2/KCNQ3 channels can cause benign familial neonatal convulsions (BFNC). We describe the immunohistochemical staining of adult and developing mouse brain using an antibody directed against the N-terminus of KCNQ3 channels (KCNQ3N). A widespread KCNQ3N immunoreactivity predominantly of neuropil but also of somata was detected in different regions of the adult mouse brain, in particular in the hippocampus, cortex, thalamus and cerebellum. This staining pattern appeared gradually and became more intense during development. In the pyramidal cell layer of the hippocampus, the im…

Identification of High-Risk Atypical Meningiomas According to Semantic and Radiomic Features

2020

Up to 60% of atypical meningiomas (World Health Organization (WHO) grade II) reoccur within 5 years after resection. However, no clear radiological criteria exist to identify tumors with higher risk of relapse. In this study, we aimed to assess the association of certain radiomic and semantic features of atypical meningiomas in MRI with tumor recurrence. We identified patients operated on primary atypical meningiomas in our department from 2007 to 2017. An analysis of 13 quantitatively defined radiomic and 11 qualitatively defined semantic criteria was performed based on preoperative MRI scans. Imaging characteristics were assessed along with clinical and survival data. The analysis include…

Longitudinal imaging and evaluation of SAH-associated cerebral large artery vasospasm in mice using micro-CT and angiography

2019

Longitudinal in vivo imaging studies characterizing subarachnoid hemorrhage (SAH)-induced large artery vasospasm (LAV) in mice are lacking. We developed a SAH-scoring system to assess SAH severity in mice using micro CT and longitudinally analysed LAV by intravenous digital subtraction angiography (i.v. DSA). Thirty female C57Bl/6J-mice (7 sham, 23 SAH) were implanted with central venous ports for repetitive contrast agent administration. SAH was induced by filament perforation. LAV was assessed up to 14 days after induction of SAH by i.v. DSA. SAH-score and neuroscore showed a highly significant positive correlation (rsp = 0.803, p < 0.001). SAH-score and survival showed a negative sig…

Local Delivery of Nimodipine by Prolonged-Release Microparticles—Feasibility, Effectiveness and Dose-Finding in Experimental Subarachnoid Hemorrhage

2012

Background and purposeTo investigate the effect of locally applied nimodipine prolonged-release microparticles on angiographic vasospasm and secondary brain injury after experimental subarachnoid hemorrhage (SAH).Methods70 male Wistar rats were categorized into three groups: 1) sham operated animals (control), 2) animals with SAH only (control) and the 3) treatment group. SAH was induced using the double hemorrhage model. The treatment group received different concentrations (20%, 30% or 40%) of nimodipine microparticles. Angiographic vasospasm was assessed 5 days later using digital subtraction angiography (DSA). Histological analysis of frozen sections was performed using H&E-staining as …

Immunohistochemical analysis of KCNQ2 potassium channels in adult and developing mouse brain

2005

The syndrome of benign familial neonatal convulsions (BFNC) is characterized by seizures starting within the first days of life and disappearing within weeks to months. BFNC is caused by loss-of-function mutations in the potassium channels KCNQ2 and KCNQ3 which can well explain the resulting neuronal hyperexcitability. However, it is not understood why seizures predominantly occur in the neonatal period. A potential explanation might be a change in the expression pattern of these channels during development. We therefore performed an immunohistochemical analysis of mouse brain slices at different stages of postnatal development using an antibody recognizing the C-terminus of the KCNQ2 chann…

Regression of advanced rat and human gliomas by local or systemic treatment with oncolytic parvovirus H-1 in rat models

2010

Oncolytic virotherapy is a potential treatment modality under investigation for various malignancies including malignant brain tumors. Unlike some other natural or modified viruses that show oncolytic activity against cerebral neoplasms, the rodent parvovirus H-1 (H-1PV) is completely apathogenic in humans. H-1PV efficiently kills a number of tumor cells without harm to corresponding normal ones. In this study, the concept of H-1PV-based virotherapy of glioma was tested for rat (RG-2 cell-derived) and for human (U87 cell-derived) gliomas in immunocompetent and immunodeficient rat models, respectively. Large orthotopic rat and human glioma cell-derived tumors were treated with either single …

Functional Improvement after Photothrombotic Stroke in Rats Is Associated with Different Patterns of Dendritic Plasticity after G-CSF Treatment and G…

2016

We have previously shown that granulocyte-colony stimulating factor (G-CSF) treatment alone, or in combination with constraint movement therapy (CIMT) either sequentially or concomitantly, results in significantly improved sensorimotor recovery after photothrombotic stroke in rats in comparison to untreated control animals. CIMT alone did not result in any significant differences compared to the control group (Diederich et al., Stroke, 2012;43:185-192). Using a subset of rat brains from this former experiment the present study was designed to evaluate whether dendritic plasticity would parallel improved functional outcomes. Five treatment groups were analyzed (n = 6 each) (i) ischemic contr…

Extracranial metastasizing solitary fibrous tumors (SFT) of meninges: Histopathological features of a case with long-term follow-up

2012

Extrapleural solitary fibrous tumors are uncommon mesenchymal neoplasms frequently observed in middle-aged adults and are classified, according to the WHO classification of soft tissue tumors, as part of the hemangiopericytoma tumor group. However, these two entities remain separated in the WHO classification of tumors of the central nervous system. In fact, meningeal solitary fibrous tumors are believed to be benign lesion and only in a minority of cases local relapses have been described, although detailed survival clinical studies on solitary fibrous tumors of meninges are rare. In contrast to hemangiopericytoma, which frequently shows distant extracranial metastases, such an event is ex…

Neuroprotective effect of ceftriaxone on the penumbra in a rat venous ischemia model.

2012

Glutamate transporter-1 (GLT-1) maintains low concentrations of extracellular glutamate by removing glutamate from the extracellular space. It is controversial, however, whether upregulation of GLT-1 is neuroprotective under all ischemic/hypoxic conditions. Recently, a neuroprotective effect of preconditioning with a β-lactam antibiotic ceftriaxone (CTX) that increases expression of GLT-1 has been reported in animal models of focal ischemia. On the other hand, it is said that CTX does not play a neuroprotective role in an in vitro study. Thus, we examined the effect of CTX on ischemic injury in a rat model of two-vein occlusion (2VO). This model mimics venous ischemia during, e.g. tumor sur…

Prevention of an increase in cortical ligand binding to AMPA receptors may represent a novel mechanism of endogenous brain protection by G-CSF after …

2016

PURPOSE Using G-CSF deficient mice we recently demonstrated neuroprotective properties of endogenous G-CSF after ischemic stroke. The present follow-up study was designed to check, whether specific alterations in ligand binding densities of excitatory glutamate or inhibitory GABAA receptors may participate in this effect. METHODS Three groups of female mice were subjected to 45 minutes of MCAO: wildtype, G-CSF deficient and G-CSF deficient mice substituted with G-CSF. Infarct volumes were determined after 24 hours and quantitative in vitro receptor autoradiography was performed using [3H]MK-801, [3H]AMPA and [3H]muscimol for labeling of NMDA, AMPA and GABAA receptors, respectively. Ligand b…

Mice with experimental antiphospholipid syndrome display hippocampal dysfunction and a reduction of dendritic complexity in hippocampal CA1 neurones

2015

Aims The antiphospholipid syndrome (APS) is an autoimmune disease characterized by high titres of auto-antibodies (aPL) leading to thrombosis and consequent infarcts. However, many affected patients develop neurological symptoms in the absence of stroke. Similarly, in a mouse model of this disease (eAPS), animals consistently develop behavioural abnormalities despite lack of ischemic brain injury. Therefore, the present study was designed to identify structural alterations of hippocampal neurones underlying the neurological symptoms in eAPS. Methods Adult female Balb/C mice were subjected to either induction of eAPS by immunization with β2-Glycoprotein 1 or to a control group. After sixteen…

Nonmetastatic Medulloblastoma of Early Childhood: Results From the Prospective Clinical Trial HIT-2000 and An Extended Validation Cohort

2020

PURPOSE The HIT-2000-BIS4 trial aimed to avoid highly detrimental craniospinal irradiation (CSI) in children < 4 years of age with nonmetastatic medulloblastoma by systemic chemotherapy, intraventricular methotrexate, and risk-adapted local radiotherapy. PATIENTS AND METHODS From 2001-2011, 87 patients received systemic chemotherapy and intraventricular methotrexate. Until 2006, CSI was reserved for nonresponse or progression. After 2006, local radiotherapy was introduced for nonresponders or patients with classic medulloblastoma (CMB) or large-cell/anaplastic medulloblastoma (LCA). DNA methylation profiles of infantile sonic hedgehog-activated medulloblastoma (SHH-INF) were subdivided i…

Neuroprotective effect of Fn14 deficiency is associated with induction of the granulocyte-colony stimulating factor (G-CSF) pathway in experimental s…

2010

Using a transgenic mouse model of ischemic stroke we checked for a possible interaction of antiphospholipid antibodies (aPL) which often cause thromboses as well as central nervous system (CNS) involvement under non-thrombotic conditions and the TWEAK/Fn14 pathway known to be adversely involved in inflammatory and ischemic brain disease. After 7 days, infarct volumes were reduced in Fn14 deficient mice and were further decreased by aPL treatment. This was associated with strongest increase of the endogenous neuroprotective G-CSF/G-CSF receptor system. This unexpected beneficial action of aPL is an example for a non-thrombogenic action and the double-edged nature of aPL.

Resection of C6 gliomas in rats with the aid of the waterjet technique

2016

While clinically the safety and efficacy of waterjet resection of brain tumors have been shown, evidence that waterjet dissection improves tumor resection radicality in comparison with conventional techniques is still missing. In the present study, resection radicality and tumor-free long-term survival of both techniques were evaluated in a C6-glioma model.Fifty-thousand C6-glioma cells were stereotactically transplanted in the left frontal lobe of 100 male Sprague-Dawley rats. After MRI-scanning for evaluation of tumor extension, microsurgical tumor resection was performed with conventional techniques (n=50) or with the waterjet dissector at pressures of 6bar (n=50). Twenty-five animals of…

Gene expression of neuregulin-1 isoforms in different brain regions of elderly schizophrenia patients

2010

One important risk gene in schizophrenia is neuregulin-1 (NRG1), which is expressed in different isoforms in the brain. To determine if alterations of NRG1 are present in schizophrenia, we measured gene expression of NRG1 and its main isoforms as well as the impact of genetic variation of NRG1 in an exploratory study examining three brain regions instead of only one as published so far. In all, we examined post-mortem samples from 11 schizophrenia patients and eight normal subjects. We investigated gene expression of total NRG1 and isoforms I, II and III by real-time PCR in the prefrontal cortex (Brodmann areas 9 and 10) and right hippocampal tissue. For the genetic study, we genotyped the …

Ischemic Preconditioning: Postischemic Structural Changes in the Brain

2008

Ischemic brain damage can be prevented or at least significantly reduced when there is a preceding brief ischemic period that does not exceed the threshold for tissue damage--a phenomenon termed "ischemic preconditioning" (ischemic PC). Experimental PC in rodents is now considered to be a model for transient ischemic attacks in humans, and there is increasing hope for translating the knowledge of underlying mechanisms in the animal models into the clinic to enhance endogenous neuroprotective mechanisms in patients with stroke. However, although PC was originally defined as a subtoxic stimulus without any morphologic damage, there is a growing body of evidence from studies using sensitive te…

MBCL-07. NON-METASTATIC MEDULLOBLASTOMA OF EARLY CHILDHOOD: RESULTS FROM THE PROSPECTIVE CLINICAL TRIAL HIT-2000 AND AN EXTENDED VALIDATION COHORT

2020

Abstract OBJECTIVE To avoid craniospinal irradiation (CSI) in children younger than four years with non-metastatic medulloblastoma by chemotherapy, intraventricular methotrexate and risk-adapted local radiotherapy. PATIENTS AND METHODS Eighty-seven patients received systemic chemotherapy and intraventricular methotrexate. Until 2006, CSI was reserved for non-response or progression. After 2006, local radiotherapy was introduced for non-responders or classic (CMB), anaplastic or large-cell medulloblastoma (LCA). Infantile SHH-activated medulloblastomas (SHH_INF) were subdivided by DNA-methylation profiling. Survival in SHH_INF subtypes were also assessed in a validation cohort (n=71). RESULT…

Identification of an Immunogenic Medulloblastoma-Specific Fusion Involving EPC2 and GULP1

2021

Medulloblastoma is the most common malignant brain tumor in children. Immunotherapy is yet to demonstrate dramatic results in medulloblastoma, one reason being the low rate of mutations creating new antigens in this entity. In tumors with low mutational burden, gene fusions may represent a source of tumor-specific neoantigens. Here, we reviewed the landscape of fusions in medulloblastoma and analyzed their predicted immunogenicity. Furthermore, we described a new in-frame fusion protein identified by RNA-Seq. The fusion involved two genes on chromosome 2 coding for the enhancer of polycomb homolog 2 (EPC2) and GULP PTB domain containing engulfment adaptor 1 (GULP1) respectively. By qRT-PCR …

Evaluation of Resection Margin after Image-Guided Dural Tail Resection in Convexity Meningiomas

2021

Infiltration of adjacent dura with meningioma cells is a common phenomenon. Wide resection of the dural tail (DT) to achieve a gross total resection is a general recommendation. We aimed to investigate a tumor cell infiltration of the DT after image-guided resection of convexity meningiomas. The study’s inclusion criteria were the diagnosis of convexity meningioma, planned Simpson I° resection, and an identifiable DT. Intraoperative image-guidance was applied to identify the outer edge of the DT and to guide resection. After resection, en-bloc specimen or four samples of outermost pieces of DT in case of piecemeal resection were sent for histological analysis. In addition to resection margi…

Principles and requirements for stroke recovery science

2020

The disappointing results in bench-to-bedside translation of neuroprotective strategies caused a certain shift in stroke research towards enhancing the endogenous recovery potential of the brain. One reason for this focus on recovery is the much wider time window for therapeutic interventions which is open for at least several months. Since recently two large clinical studies using d-amphetamine or fluoxetine, respectively, to enhance post-stroke neurological outcome failed again it is a good time for a critical reflection on principles and requirements for stroke recovery science. In principal, stroke recovery science deals with all events from the molecular up to the functional and behav…

Does granulocyte-colony stimulating factor stimulate peripheral nerve regeneration? An experimental study on traumatic lesion of the sciatic nerve in…

2021

Aim of the study. To analyse the therapeutic potential of granulocyte-colony stimulating factor (G-CSF) treatment using a rat model of traumatic sciatic nerve lesion. Clinical rationale for the study. G-CSF has proven strong neurotrophic properties in various models of ischaemic and traumatic brain injury. Fewer studies exist regarding the influence of G-CSF on posttraumatic peripheral nerve regeneration. Currently, the possibilities of pharmacological prevention or treatment of mechanical nerve injury are limited, and there is an urgent need to find new treatment strategies applicable in clinical situations. Material and methods . A controlled traumatic right sciatic nerve lesion was set u…

Reduced oxytocin receptor gene expression and binding sites in different brain regions in schizophrenia: A post-mortem study

2016

Schizophrenia is a severe neuropsychiatric disorder with impairments in social cognition. Several brain regions have been implicated in social cognition, including the nucleus caudatus, prefrontal and temporal cortex, and cerebellum. Oxytocin is a critical modulator of social cognition and the formation and maintenance of social relationships and was shown to improve symptoms and social cognition in schizophrenia patients. However, it is unknown whether the oxytocin receptor is altered in the brain. Therefore, we used qRT-PCR and Ornithine Vasotocin Analog ([125I]OVTA)-based receptor autoradiography to investigate oxytocin receptor expression at both the mRNA and protein level in the left p…

Histology and Infarct Volume Determination

2010

A Neuroprotective Function for the Hematopoietic Protein Granulocyte-Macrophage Colony Stimulating Factor (GM-CSF)

2007

Granulocyte-macrophage colony-stimulating factor (GM-CSF) is a hematopoietic cytokine responsible for the proliferation, differentiation, and maturation of cells of the myeloid lineage, which was cloned more than 20 years ago. Here we uncovered a novel function of GM-CSF in the central nervous system (CNS). We identified the GM-CSF α-receptor as an upregulated gene in a screen for ischemia-induced genes in the cortex. This receptor is broadly expressed on neurons throughout the brain together with its ligand and induced by ischemic insults. In primary cortical neurons and human neuroblastoma cells, GM-CSF counteracts programmed cell death and induces BCL-2 and BCL-Xl expression in a dose- a…

DOSE-RELATED EFFICACY OF A CONTINUOUS INTRACISTERNAL NIMODIPINE TREATMENT ON CEREBRAL VASOSPASM IN THE RAT DOUBLE SUBARACHNOID HEMORRHAGE MODEL

2009

Objective Intracisternal continuous therapy is a concept in the treatment of cerebral vasospasm after subarachnoid hemorrhage. The purpose of the current study was to investigate the effect of intracisternal nimodipine after induced vasospasm. Methods Sixty-five male Wistar rats were randomized into 4 groups: the control sham-operated group, the control subarachnoid hemorrhage-only group, and the treatment groups receiving 5 or 10 microL/hour of intracisternal nimodipine continuously for 5 days via subcutaneously implanted Alzet osmotic pumps (Durect Corp., Cupertino, CA). Vasospasm was analyzed 5 days later by means of digital subtraction angiography. Morphological examination of the brain…

Towards a glioma model for surgical technique evaluation in the rat.

2013

Evaluation of new surgical techniques in animal models is frequently challenging. This article describes the pitfalls, peculiarities and the final best applicable model for evaluating surgical techniques for glioma resection.The C6 glioma cell line and the Sprague-Dawley rat strain were selected. Fifty-thousand glioma cells were stereotactically transplanted in the left hemisphere of 137 male adult rats. Evaluation of solid tumour formation, tumour growth and scheduling of surgical resection was performed by MR scanning at 1, 2, and 4 weeks after transplantation and 3 and 6 months after tumour resection. Microsurgical tumour resection was performed with conventional techniques or with the w…

Childhood supratentorial ependymomas with YAP1-MAMLD1 fusion: an entity with characteristic clinical, radiological, cytogenetic and histopathological…

2018

Ependymoma with YAP1-MAMLD1 fusion is a rare, recently described supratentorial neoplasm of childhood, with few cases published so far. We report on 15 pediatric patients with ependymomas carrying YAP1-MAMLD1 fusions, with their characteristic histopathology, immunophenotype and molecular/cytogenetic, radiological and clinical features. The YAP1-MAMLD1 fusion was documented by RT-PCR/Sanger sequencing, and tumor genomes were studied by molecular inversion probe (MIP) analysis. Significant copy number alterations were identified by GISTIC (Genomic Identification of Significant Targets in Cancer) analysis. All cases showed similar histopathological features including areas of high cellularity…

Distribution of the hematopoietic growth factor G-CSF and its receptor in the adult human brain with specific reference to Alzheimer's disease

2013

The granulocyte colony-stimulating factor (G-CSF), being a member of the hematopoietic growth factor family, is also critically involved in controlling proliferation and differentiation of neural stem cells. Treatment with G-CSF has been shown to result in substantial neuroprotective and neuroregenerative effects in various experimental models of acute and chronic diseases of the central nervous system. Although G-CSF has been tested in a clinical study for treatment of acute ischemic stroke, there is only fragmentary data on the distribution of this cytokine and its receptor in the human brain. Therefore, the present study was focused on the immunohistochemical analysis of the protein expr…

A new model of thromboembolic stroke in the posterior circulation of the rat

2006

The prognosis of vertebrobasilar occlusion is grave and therapeutic options are limited. The aim of the present study was to develop a new model of embolic hindbrain ischemia in the rat that closely resembles the clinical situation and that can be used to study pathophysiology and treatment options. After thoracotomy in 20 male Wistar rats, 15 animals received an injection of in vitro prepared autologous blood clots into the left vertebral artery. Five animals without clot injection served as controls. Neurological deficits were assessed in all animals 2 h after embolism. After 2 h, five animals were sacrificed to measure cerebral blood flow (CBF) by iodo-antipyridine autoradiography, and t…

Genomic profiling to assess the clonal relationship between histologically distinct intracranial tumours

2012

Detrimental Effects of 60 kHz Sonothrombolysis in Rats with Middle Cerebral Artery Occlusion

2008

Recent studies have raised concerns about the safety of low frequency ultrasound in transcranial therapeutic application in cerebral ischemia. This study was designed to evaluate safety aspects and potential deleterious effects of low frequency, 60 kHz ultrasound in treatment of experimental middle cerebral artery occlusion (MCAO) in rats. Forty-five male Wistar rats were submitted to either temporary (90 min; groups I and II) or permanent MCAO (groups III and IV) using the suture technique. All animals received recombinant tissue plasminogen activator (rt-PA) starting 90 min after the beginning of occlusion. Groups I and III were additionally treated with 60 kHz ultrasound (time average ac…

Inhibition of lymphocyte trafficking shields the brain against deleterious neuroinflammation after stroke

2011

T lymphocytes are increasingly recognized as key modulators of detrimental inflammatory cascades in acute ischaemic stroke, but the potential of T cell-targeted therapy in brain ischaemia is largely unexplored. Here, we characterize the effect of inhibiting leukocyte very late antigen-4 and endothelial vascular cell adhesion molecule-1-mediated brain invasion-currently the most effective strategy in primary neuroinflammatory brain disease in murine ischaemic stroke models. Very late antigen-4 blockade by monoclonal antibodies improved outcome in models of moderate stroke lesions by inhibiting cerebral leukocyte invasion and neurotoxic cytokine production without increasing the susceptibilit…

Brain-Derived Neurotrophic Factor But Not Forced Arm Use Improves Long-Term Outcome After Photothrombotic Stroke and Transiently Upregulates Binding …

2008

Background and Purpose— Both application of neurotrophic factors like brain-derived neurotrophic factor (BDNF) and constraint-induced movement therapy like forced arm use have been shown to potentially improve outcome after stroke. The aim of the present study was to check whether postischemic long-term outcome correlates to specific modifications in the abundance of various neurotransmitter receptors. Methods— Adult male Wistar rats were subjected to photothrombotic ischemia and assigned to various treatment groups (n=5 each) with end points at 3 and 6 weeks: (1) ischemic control (saline); (2) BDNF (ischemia, 20 μg BDNF); (3) forced arm use (ischemia, saline, and ipsilateral plaster cast …

Fostering Poststroke Recovery: Towards Combination Treatments.

2016

Despite countless experimental studies demonstrating neuroprotective effects in the treatment of acute ischemic stroke, they all could not live up their promises when it came to translation into patients. Recent research therefore increasingly shifted to therapies enhancing poststroke recovery with the important advantage of a much wider time window up to several months. To further increase poststroke recovery, the combination of different therapy principles is a logical step. However, several burning questions concerning the modus of combination are unresolved. This review will briefly mention the principle poststroke recovery approaches and discuss the mostly used combination designs. In …

Long-term gene expression changes in the cortex following cortical ischemia revealed by transcriptional profiling

2006

Cerebral ischemia evokes changes in gene expression time-dependently after the ischemic event. Most studies on transcriptional changes following ischemia have centered on relatively early postischemic time points, and detected multiple genes relevant to neuronal cell death. However, functional outcome after ischemia depends critically on adaptations of the postischemic brain. Plasticity may derive from network-inherent changes, or from the formation of new nerve cells in the CNS. We have screened for gene expression changes up to 3 weeks following a limited photothrombotic cortical insult in the rat sensorimotor cortex by using the sensitive restriction-mediated differential display (RMDD) …

Exploiting Gangliosides for the Therapy of Ewing’s Sarcoma and H3K27M-Mutant Diffuse Midline Glioma

2021

Simple Summary Osteosarcoma, Ewing’s sarcoma, and H3K27M-mutant diffuse midline glioma are rare but aggressive malignancies occurring mainly in children. Due to their rareness and often fatal course, drug development is challenging. Here, we repurposed the existing drugs dinutuximab and eliglustat and investigated their potential to directly target or indirectly modulate the tumor cell-specific ganglioside GD2. Our data suggest that targeting and/or modulating tumor cell-specific GD2 may offer a new therapeutic strategy for the above mentioned tumor entities. Abstract The ganglioside GD2 is an important target in childhood cancer. Nevertheless, the only therapy targeting GD2 that is approve…

Propofol Impairs Neurogenesis and Neurologic Recovery and Increases Mortality Rate in Adult Rats After Traumatic Brain Injury*

2013

Objective: Limited data are available on the influence of sedation for critical care therapy with the widely used anesthetic propofol on recovery from acute traumatic brain injury. To establish the influence of propofol on endogenous neurogenesis and functional recovery after traumatic brain injury, rats were sedated with propofol either during or 2 hours after experimental traumatic brain injury. Design: Randomized controlled animal study. Setting: University research laboratory. Subjects: One hundred sixteen male Sprague Dawley rats. Interventions: Mechanical brain lesion by controlled cortical impact. Measurements and Main Results: This study investigated the dose-dependent influence of …

Anti-prothrombin autoantibodies enriched after infection with SARS-CoV-2 and influenced by strength of antibody response against SARS-CoV-2 proteins

2021

Antiphospholipid antibodies (aPL), assumed to cause antiphospholipid syndrome (APS), are notorious for their heterogeneity in targeting phospholipids and phospholipid-binding proteins. The persistent presence of Lupus anticoagulant and/or aPL against cardiolipin and/or β2-glycoprotein I have been shown to be independent risk factors for vascular thrombosis and pregnancy morbidity in APS. aPL production is thought to be triggered by–among other factors–viral infections, though infection-associated aPL have mostly been considered non-pathogenic. Recently, the potential pathogenicity of infection-associated aPL has gained momentum since an increasing number of patients infected with Severe Acu…

Neurological impairment in experimental antiphospholipid syndrome is associated with increased ligand binding to hippocampal and cortical serotonergi…

2013

The antiphospholipid syndrome (APS) is an autoimmune disease where the presence of high titers of circulating autoantibodies causes thrombosis with consecutive infarcts. In experimental APS (eAPS), a mouse model of APS, behavioral abnormalities develop in the absence of vessel occlusion or infarcts. Using brain hemispheres of control and eAPS mice with documented neurological and cognitive deficits, we checked for lymphocytic infiltration, activation of glia and macrophages, as well as alterations of ligand binding densities of various neurotransmitter receptors to unravel the molecular basis of this abnormal behavior. Lymphocytic infiltrates were immunohistochemically characterized using a…

Altered receptor binding densities in experimental antiphospholipid syndrome despite only moderately enhanced autoantibody levels and absence of beha…

2013

Abstract Experimental antiphospholipid syndrome (eAPS) in Balb/c mice causes neuropsychiatric abnormalities including hyperactivity, increased explorative behavior and cognitive deficits. Recently, we have demonstrated that these behavioral changes were linked to an upregulation of serotonergic 5-HT1A receptor binding densities in cortical and hippocampal regions while excitatory and inhibitory neurotransmitter receptors remain largely unchanged. To examine whether the observed behavioral features depend on a critical antibody concentration, mice with only moderately enhanced antiphospholipid antibodies (aPL), about 50–80% of high levels, were analyzed and compared to controls. The staircas…

PNR-35CNS HGNET-BCOR - MOLECULAR CHARACTERIZATION AND IDENTIFICATION OF POSSIBLE THERAPEUTIC TARGETS OF A NEW BRAIN TUMOR ENTITY

2016

Waterjet Dissection of Peripheral Nerves: An Experimental Study of the Sciatic Nerve of Rats

2010

BACKGROUND: Although waterjet dissection has been well evaluated in intracranial pathologies, little is known of its qualities in peripheral nerve surgery. Theoretically, the precise dissection qualities could support the separation of nerves from adjacent tissues and improve the preservation of nerve integrity in peripheral nerve surgery. OBJECTIVE: To evaluate the potential of the new waterjet dissector in peripheral nerve surgery. METHODS: Waterjet dissection with pressures of 20 to 80 bar was applied on the sciatic nerves of 101 rats. The effect of waterjet dissection on the sciatic nerve was evaluated by clinical tests, neurophysiological examinations, and histopathological studies up …

NECAB2 participates in an endosomal pathway of mitochondrial stress response at striatal synapses

2021

Synaptic signaling depends on ATP generated by mitochondria. Due to extensive connectivity, the striatum is especially vulnerable to mitochondrial dysfunction and thus requires efficient mitochondrial quality control. We found that the neuronal calcium-binding protein NECAB2 ensures synaptic function in the striatum by increasing mitochondrial efficiency. NECAB2 associates with early endosomes and mitochondria at striatal synapses. Loss of NECAB2 dysregulates proteins of the endosomal ESCRT machinery and oxidative phosphorylation. Mitochondria from NECAB2-deficient mice are more abundant but less efficient. These mitochondria exhibit increased respiration and superoxide production but produ…

Pravastatin treatment causes a shift in the balance of hippocampal neurotransmitter binding densities towards inhibition

2009

Since pravastatin, a HMG-CoA reductase inhibitor, has recently been shown to reduce infarct volumes and glutamate release in a rat model of ischemic stroke, the aim of the present study was to investigate whether this neuroprotective effect may be due to a modulation of excitatory and inhibitory neurotransmitter receptors. Therefore, Wistar rats were treated six times in 4 days with pravastatin or saline and allowed to survive for 6 hours or 5 days (n=10 per time point and group), respectively. Using quantitative receptor autoradiography, ligand binding densities of [(3)H]MK-801, [(3)H]AMPA, and [(3)H]muscimol for labeling of NMDA, AMPA, and GABA(A) receptors were analyzed in sensorimotor c…

The experimental antiphospholipid syndrome: an invaluable tool to study autoimmunity-induced neurodegeneration

2014

cells and its activation inhibits their differentiation and remyelination. These suggest a possible role of CNS TLR2 in progressive autoimmune demyelination. Methods: We examined the effects of intra-cerebro-ventricular (ICV) injection of Zymozan, a TLR2 agonist, on the clinical and pathological course of EAE. The survival and clinical scores were monitored; demyelination and axonal loss were quantified by gold-black and Bielschowsky stains, and the nature of neuro-inflammatory response was characterized by TLR2, IBA-1 and CD3 stainings and PCR for immune cytokines. Immune cells were isolated from EAE brain tissue and their proliferative response to the autoantigen (PLP peptide) or Concaval…

Postischemic Brain Infiltration of Leukocyte Subpopulations Differs among Murine Permanent and Transient Focal Cerebral Ischemia Models

2012

Cellular and humoral inflammations play important roles in ischemic brain injury. The effectiveness of immunomodulatory therapies may critically depend on the chosen experimental model. Our purpose was to compare the post-ischemic neuroinflammation among murine permanent and transient middle cerebral artery occlusion (MCAO) models. Permanent MCAO was induced by transtemporal electrocoagulation and 30 minutes or 90 minutes transient MCAO was induced by intraluminal filament in C57BL/6 mice. Infiltration of leukocyte subpopulations was quantified by immunohistochemistry and fluorescence-activated cell sorting. Cerebral cytokine and adhesion molecule expression was measured by real-time polyme…

Induction of the cytokine TWEAK and its receptor Fn14 in ischemic stroke.

2008

Stroke outcome is determined by delayed neuronal cell death and edema formation. TWEAK, a cytokine of the TNF superfamily, and its membrane receptor Fn14 promote ischemia-induced neuronal apoptosis and leakage of the blood-brain barrier. Both TWEAK and Fn14 are upregulated in experimental stroke models. In this study, we investigated whether TWEAK and Fn14 are upregulated in stroke patients. We measured serum concentrations of TWEAK in stroke patients and matched control subjects by ELISA. Expression of Fn14 in the brain was evaluated by real-time RT-PCR and immunohistochemistry. TWEAK serum concentrations were elevated in stroke patients. In autopsy samples, we found elevated mRNA levels o…

In Vitro Effects of Antiphospholipid Syndrome-IgG Fractions and Human Monoclonal Antiphospholipid IgG Antibody on Human Umbilical Vein Endothelial Ce…

2009

It has been shown that stimulation of endothelial cells and monocytes by antiphospholipid antibodies leads to a prothrombotic state involving upregulation of tissue factor (TF). We examined the in vitro effects of IgG fractions from patients with antiphospholipid syndrome (APS) and of a β-2-glycoprotein 1-independent human monoclonal antiphospholipid antibody (HL-5B) on human umbilical vein endothelial cells (HUVEC) in comparison to untreated cell controls and to exposure to monoclonal IgG control antibody. We also examined the effect of recombinant monocyte chemoattractant protein-1 (MCP-1) on peripheral blood monocytes. Stimulation of endothelial cells with APS IgG fractions or HL-5B resu…

Endocannabinoids mediate neuroprotection after transient focal cerebral ischemia.

2008

The endocannabinoids anandamide (AEA) and palmitoylethanolamide (PEA) act as endogenous protective factors of the brain, using different pathways of neuroprotection against neuronal damage. Although several in vivo and in vitro studies confirmed the neuroprotective efficacy of endocannabinoids, no experimental settings compare and explore the neuroprotective potential of AEA and PEA in an acute stroke model. In this study, we investigated the neuroprotective potential by infarct measurement after high (30 mg/kg body weight) and low dosage administration (10 mg/kg body weight) of the endocannabinoid PEA in 49 male Wistar rats. In additions we studied infarct volumes of 22 male Wistar rats re…

A human multisystem disorder with autoinflammation, leukoencephalopathy and hepatopathy is caused by mutations in C2orf69

2021

AbstractBackgroundDeciphering the function of the many genes previously classified as uncharacterized “open reading frame” (orf) completes our understanding of cell function and its pathophysiology.MethodsWhole-exome sequencing, yeast 2-hybrid and transcriptome analyses together with molecular characterization are used here to uncover the function of the C2orf69 gene.ResultsWe identify loss-of-function mutations in the uncharacterized C2orf69 gene in eight individuals with brain abnormalities involving hypomyelination and microcephaly, liver dysfunction and recurrent autoinflammation. C2orf69 contains an N-terminal signal peptide that is required and sufficient for mitochondrial localizatio…

Meta-analysis of the efficacy of different training strategies in animal models of ischemic stroke.

2013

Background and Purpose— Although several studies have shown beneficial effects of training in animal stroke models, the most effective training strategy and the optimal time to initiate training have not been identified. The present meta-analysis was performed to compare the efficacy of different training strategies and to determine the optimal time window for training in animal stroke models. Methods— We searched the literature for studies analyzing the efficacy of training in animal models of ischemic stroke. Training was categorized into forced physical training, voluntary physical training, constraint-induced movement therapy, and skilled reaching training. Two reviewers independently …

Neuronavigation and epilepsy surgery

2010

Resective epilepsy surgery is an elective therapy indicated in focal epilepsy patients who are resistant to pharmacotherapy. Every effort should be undertaken to perform the procedures as safe and less traumatic as possible. Neuronavigation could represent a suitable tool to reduce surgical morbidity and increase surgical radicality. Here, we present a series of 41 patients who were operated on for medically intractable epilepsy using neuronavigation. Overall, complication rate was 17% with a favourable seizure outcome of 88% (Engel’s class I/II). Our data suggest that neuronavigation is a valuable surgical technique to accomplish a favourable outcome in epilepsy surgery.

Evaluation of a murine single-blood-injection SAH model.

2014

The molecular pathways underlying the pathogenesis after subarachnoid haemorrhage (SAH) are poorly understood and continue to be a matter of debate. A valid murine SAH injection model is not yet available but would be the prerequisite for further transgenic studies assessing the mechanisms following SAH. Using the murine single injection model, we examined the effects of SAH on regional cerebral blood flow (rCBF) in the somatosensory (S1) and cerebellar cortex, neuro-behavioural and morphological integrity and changes in quantitative electrocorticographic and electrocardiographic parameters. Micro CT imaging verified successful blood delivery into the cisterna magna. An acute impairment of …

JCB887052 Supplemetal Material - Supplemental material for Longitudinal imaging and evaluation of SAH-associated cerebral large artery vasospasm in m…

2019

Supplemental material, JCB887052 Supplemetal Material for Longitudinal imaging and evaluation of SAH-associated cerebral large artery vasospasm in mice using micro-CT and angiography by Vanessa Weyer, Máté E Maros, Andrea Kronfeld, Stefanie Kirschner, Christoph Groden, Clemens Sommer, Yasemin Tanyildizi, Martin Kramer and Marc A Brockmann in Journal of Cerebral Blood Flow & Metabolism