Neutrophil extracellular traps in CSF and serum of dogs with steroid-responsive meningitis-arteritis.

In steroid-responsive meningitis-arteritis (SRMA), inflammatory dysregulation is driven by neutrophilic granulocytes resulting in purulent leptomeningitis. Neutrophils can generate neutrophil extracellular traps (NET). Uncontrolled NET-formation or impaired NET-clearance evidently cause tissue and organ damage resulting in immune-mediated diseases. The aim of the study was to verify that NET-formation is detectable in ex vivo samples of acute diseased dogs with SRMA by visualizing and measuring NET-markers in serum and cerebrospinal fluid (CSF) samples. CSF-samples of dogs with acute SRMA (n = 5) and in remission (n = 4) were examined using immunofluorescence (IF)-staining of DNA-histone-1-complexes, myeloperoxidase and citrullinated Histone H3 (H3Cit). Immunogold-labeling of H3Cit and neutrophil elastase followed by transmission electron microscopy (TEM) were used to determine ultrastructural NET-formation in the CSF of one exemplary dog. H3Cit-levels and DNase-activity were measured in CSF and serum samples using an H3Cit-ELISA and a DNase-activity-assay, respectively in patients with the following diseases: acute SRMA (n = 34), SRMA in remission (n = 4), bacterial encephalitis (n = 3), meningioma with neutrophilic inflammation (n = 4), healthy dogs (n = 6). NET-formation was detectable with IF-staining in n = 3/5 CSF samples of dogs with acute SRMA but were not detectable during remission. Vesicular NET-formation was detectable in one exemplary dog using TEM. DNase-activity was significantly reduced in dogs suffering from acute SRMA compared to healthy control group (p < 0.0001). There were no statistical differences of H3Cit levels in CSF or serum samples of acute diseased dogs compared to dogs under treatment, dogs suffering from meningioma or bacterial encephalitis or the healthy control group. Our findings demonstrate that NET-formation and insufficient NET-clearance possibly drive the immunologic dysregulation and complement the pathogenesis of SRMA. The detection of NETs in SRMA offers many possibilities to explore the aetiopathogenetic influence of this defence mechanism of the innate immune system in infectious and non-infectious canine neuropathies.

Current definition, diagnosis, and treatment of canine and feline idiopathic vestibular syndrome.

Idiopathic vestibular syndrome (IVS) is one of the most common neurological disorders in veterinary medicine. However, its diagnosis and treatment varies between publications. The aim of the current study was to gather experts' opinion about IVS definition, diagnosis, and treatment. An online-survey was used to assess neurology specialists' opinion about the definition, diagnosis and treatment of IVS. The study demonstrated that the definition, diagnosis, and treatment of IVS are largely consistent worldwide, with the EU prioritising less frequently advanced imaging and more often otoscopy to rule out other diseases. IVS was defined by most specialists as an acute to peracute, improving, non-painful peripheral vestibular disorder that often affects cats of any age and geriatric dogs. Regarding diagnosis, a detailed neurological examination and comprehensive blood tests, including thyroid values, blood pressure, and otoscopic examination, was seen as crucial. A thorough workup may also involve MRI and CSF analysis to rule out other causes of vestibular dysfunction. Treatment of IVS typically involved intravenous fluid therapy and the use of an antiemetic, with maropitant once daily being the preferred choice among specialists. Antinausea treatment was considered, however, only by a handful specialists. This survey-based study provides valuable insights from neurology experts and highlights areas that require further research to bridge the gap between theory and practice.

Biopsy Characteristics, Subtypes, and Prognostic Features in 107 Cases of Feline Presumed Immune-Mediated Polyneuropathy.

Inflammatory polyradiculoneuropathy (IMPN) is one of the causes of sudden onset of neuromuscular signs such as para-/tetraparesis in young cats. Even though most cases have a favorable outcome, persistent deficits, relapses, and progressive courses are occasionally seen. As clinical presentation does not always appear to predict outcome and risk of recurrence, this study was initiated to screen for prognostic biopsy findings in a large cohort of histologically confirmed IMPN cases with clinical follow-up. In total, nerve and muscle specimens of 107 cats with biopsy diagnosis of presumed autoreactive inflammatory polyneuropathy and 22 control cases were reviewed by two blinded raters for a set of 36 histological parameters. To identify patterns and subtypes of IMPN, hierarchical k-means clustering of 33 histologic variables was performed. Then, the impact of histological parameters on IMPN outcome was evaluated via an univariate analysis to identify variables for the final multivariate model. The data on immediate outcome and follow-up were collected from submitting neurologists using a purpose-designed questionnaire. Hierarchical k-means clustering sorted the tissues into 4 main categories: cluster 1 (44/129) represents a purely inflammatory IMPN picture, whereas cluster 2 (47/129) was accompanied by demyelinating features and cluster 3 (16/129) by Wallerian degeneration. Cluster 4 (22/129) reflects normal tissues from non-neuropathic control cats. Returned questionnaires provided detailed information on outcome in 63 animals. They were categorized into recovered and non-recovered. Thereby, fiber-invasive infiltrates by mononuclear cells and mild fiber loss in intramuscular nerve branches correlated with higher probabilities of recovery. Remyelination in semithin sections, on the other hand, is correlated with a less favorable outcome. Animals grouping in cluster 1 had a tendency to a higher probability of recovery compared to other clusters. In conclusion, diagnosis of feline IMPN from nerve and muscle biopsies allowed for the identification of histologic features that were positively or negatively correlated with outcome.

Pregabalin Add-On vs. Dose Increase in Levetiracetam Add-On Treatment: A Real-Life Trial in Dogs With Drug-Resistant Epilepsy.

Epilepsy is a common neurological disorder affecting 0.6-0.75% of dogs in veterinary practice. Treatment is frequently complicated by the occurrence of drug-resistant epilepsy and cluster seizures in dogs with idiopathic epilepsy. Only few studies are available to guide treatment choices beyond licensed veterinary drugs. The aim of the study was to compare antiseizure efficacy and tolerability of two add-on treatment strategies in dogs with drug-resistant idiopathic epilepsy. The study design was a prospective, open-label, non-blinded, comparative treatment trial. Treatment success was defined as a 3-fold extension of the longest baseline interseizure interval and to a minimum of 3 months. To avoid prolonged adherence to a presumably ineffective treatment strategy, dog owners could leave the study after the third day with generalized seizures if the interseizure interval failed to show a relevant increase. Twenty-six dogs (mean age 5.5 years, mean seizure frequency 4/month) with drug-resistant idiopathic epilepsy and a history of cluster seizures were included. Dogs received either add-on treatment with pregabalin (PGB) 4 mg/kg twice daily (14 dogs) or a dose increase in levetiracetam (LEV) add-on treatment (12 dogs). Thirteen dogs in the PGB group had drug levels within the therapeutic range for humans. Two dogs in the PGB group (14.3%; 2/14) and one dog in the LEV group (8.3%; 1/12) achieved treatment success with long seizure-free intervals from 122 to 219 days but then relapsed to their early seizure frequency 10 months after the study inclusion. The overall low success rates with both treatment strategies likely reflect a real-life situation in canine drug-resistant idiopathic epilepsy in everyday veterinary practice. These results delineate the need for research on better pharmacologic and non-pharmacologic treatment strategies in dogs with drug-resistant epilepsy.

Clinical Course and Diagnostic Findings of Biopsy Controlled Presumed Immune-Mediated Polyneuropathy in 70 European Cats.

There is a paucity of information on the clinical course and outcome of young cats with polyneuropathy. The aim of the study was to describe the clinical features, diagnostic investigations, and outcome of a large cohort of cats with inflammatory polyneuropathy from several European countries. Seventy cats with inflammatory infiltrates in intramuscular nerves and/or peripheral nerve biopsies were retrospectively included. Information from medical records and follow up were acquired via questionnaires filled by veterinary neurologists who had submitted muscle and nerve biopsies (2011-2019). Median age at onset was 10 months (range: 4-120 months). The most common breed was British short hair (25.7%), followed by Domestic short hair (24.3%), Bengal cat (11.4%), Maine Coon (8.6%) and Persian cat (5.7%), and 14 other breeds. Male cats were predominantly affected (64.3%). Clinical signs were weakness (98.6%) and tetraparesis (75.7%) in association with decreased withdrawal reflexes (83.6%) and, less commonly, cranial nerve signs (17.1%), spinal pain/hyperesthesia (12.9%), and micturition/defecation problems (14.3%). Onset was sudden (30.1%) or insidious (69.1%), and an initial progressive phase was reported in 74.3%. Characteristic findings on electrodiagnostic examination were presence of generalized spontaneous electric muscle activity (89.6%), decreased motor nerve conduction velocity (52.3%), abnormal F-wave studies (72.4%), pattern of temporal dispersion (26.1%) and unremarkable sensory tests. The clinical course was mainly described as remittent (49.2%) or remittent-relapsing (34.9%), while stagnation, progressive course or waxing and waning were less frequently reported. Relapses were common and occurred in 35.7% of the cats' population. An overall favorable outcome was reported in 79.4% of patients. In conclusion, young age at the time of diagnosis and sudden onset of clinical signs were significantly associated with recovery (p < 0.05). Clinical and electrodiagnostic features and the remittent-relapsing clinical course resembles juvenile chronic inflammatory demyelinating polyneuropathy (CIDP), as seen in human (children/adolescents), in many aspects.

[Trichinella induced polymyositis with unilateral lameness in a dog]. / Polymyositis mit einseitiger Lahmheit im Rahmen einer Trichinellose beim Hund.

A 9-year-old Cairn Terrier was presented for a right thoracic limb lameness of 3-month duration resistant to anti-inflammatory pain treatment. Blood chemistry revealed a highly elevated creatine kinase activity. An orthopedic or vascular etiology of the lameness was excluded by radiographs, computed tomography, and magnetic resonance imaging. Further workup for a neurologic or muscular etiology by electromyography, nerve conduction velocity measurement, and histology of muscle as well as nerve biopsies identified the cause of the lameness. Histology revealed a pyogranulomatous, necrotizing myositis with parasites of the species Trichinella. Furthermore different developmental stages of fungi were detected which were identified as Mucor sp. Treatment with albendazole and itraconazole significantly improved the patient's clinical signs.

Short-term and long-term effects of a minimally invasive transilial vertebral blocking procedure on the lumbosacral morphometry in dogs measured by computed tomography.

OBJECTIVE: To determine the effects of a minimally invasive transilial vertebral (MTV) blocking procedure on the computed tomographic (CT) appearance of the lumbosacral (L7/S1) junction of dogs with degenerative lumbosacral stenosis (DLSS). STUDY DESIGN: Prospective study. ANIMALS: 59 client-owned dogs with DLSS. METHODS: Lumbosacral CT images were acquired with hyperextended pelvic limbs before and after MTV in all dogs. Clinical follow-up was obtained after 1 year, including a neurologic status classified in 4 grades, and if possible, CT. Morphometric measurements (Mean ± SEM) including foraminal area, endplate distance at L7/S1 and LS angle were obtained on sets of reformatted parasagittal and sagittal CT images. RESULTS: The mean foraminal area (ForL) increased from 32.5 ± 1.7 mm2 to 59.7 ± 1.9 mm2 on the left and from 31.1 ± 1.4 mm2 to 59.1 ± 2.0 mm2 on the right (ForR) side after MTV. The mean endplate distance (EDmd) between L7/S1 increased from 3.7 ± 0.1 mm to 6.0 ± 0.1 mm, and mean lumbosacral angle (LSa) from 148.0 ± 1.1° to 170.0 ± 1.1° after MTV. CT measurements were available 1 year postoperatively in 12 cases: ForL: 41.2 ± 3.1 mm2 ; ForR: 37.9 ± 3.1 mm2 ; EDmd: 4.3 ± 0.4 mm, and LSa 157.6 ± 2.1° (values are mean and standard error of mean = SEM). All 39 dogs with long-term follow-up improved by at least 1 neurologic grade, 9/39 improving by 3 grades, 15/39 by 2 grades, and 15/39 by 1 grade. CONCLUSIONS: MTV results in clinical improvement and morphometric enlargement of the foraminal area in dogs with variable degrees of foraminal stenosis. CLINICAL RELEVANCE: MTV may be a valuable minimally invasive option for treatment of dogs with DLSS.

Nodo-paranodopathy, internodopathy and cleftopathy: Target-based reclassification of Guillain-Barré-like immune-mediated polyradiculoneuropathies in dogs and cats.

Recent views on Guillain-Barré syndrome (GBS) question the accuracy of classification into axonal and demyelinating subtypes that represent convergent neurophysiological phenotypes rather than immunological targets. Instead it has been proposed to clarify the primarily affected fibre subunit in nerve biopsies. As nerve biopsies rarely are part of routine work-up in human patients we evaluated tissues taken from companion animals affected by GBS-like polyradiculoneuropathy to screen for distribution of immune cells, targeted fibre components and segregating non-inflammatory lesions. We identified that immune responses were directed either at Schmidt-Lanterman clefts, the paranode-node complex or both. Based on infiltrative and non-inflammatory changes, four subtypes and/or stages were distinguished, some of which indicate localisation of primary target antigens while others represent convergent late stage pictures, as a consequence to epitope spreading. The impact of histological subtyping onto clinical management and prognosis remains to be evaluated in future clinical trials. Natural development and clinical manifestation of large animal dysimmune neuropathy may reflect human Guillain-Barré syndrome more accurately than experimental models and therefore provide complementary clues for translational research.

Transient neuromyopathy after bromide intoxication in a dog with idiopathic epilepsy.

A seven-year old Australian Shepherd, suffering from idiopathic epilepsy under treatment with phenobarbitone and potassium bromide, was presented with generalised lower motor neuron signs. Electrophysiology and muscle-nerve biopsies revealed a neuromyopathy.The serum bromide concentration was increased more than two-fold above the upper reference value.Clinical signs disappeared after applying diuretics and reducing the potassium bromide dose rate. This is the first case report describing electrophysiological and histopathological findings associated with bromide induced lower motor neuron dysfunction in a dog.

Canine muscle cell culture and consecutive patch-clamp measurements - a new approach to characterize muscular diseases in dogs.

BACKGROUND: The recognition of functional muscular disorders, (e.g. channelopathies like Myotonia) is rising in veterinary neurology. Morphologic (e.g. histology) and even genetic based studies in these diseases are not able to elucidate the functional pathomechanism. As there is a deficit of knowledge and skills considering this special task, the aim of the current pilot study was to develop a canine muscle cell culture system derived from muscle biopsies of healthy client-owned dogs, which allows sampling of the biopsies under working conditions in the daily veterinary practise. RESULTS: Muscular biopsies from 16 dogs of different age and breed were taken during standard surgical procedures and were stored for one to three days at 4°C in a transport medium in order to simulate shipping conditions. Afterwards biopsies were professionally processed, including harvesting of satellite cells, inducing their proliferation, differentiating them into myotubes and recultivating myotubes after long-term storage in liquid nitrogen. Myogenic origin of cultured cells was determined by immunofluorescence, immunohistology and by their typical morphology after inducing differentiation. Subsequent to the differentiation into myotubes feasibility of patch-clamp recordings of voltage gated ion channels was successfully. CONCLUSION: We have developed a canine muscle cell culture system, which allows sampling of biopsies from young and old dogs of different breeds under practical conditions. Patch clamp measurements can be carried out with the cultured myotubes demonstrating potential of these cells as source for functional research.

Electroencephalographic recordings in dogs suffering from idiopathic and symptomatic epilepsy: diagnostic value of interictal short time EEG protocols supplemented by two activation techniques.

The diagnostic value of interictal short time electroencephalographic (EEG) recordings in epileptic dogs under general anaesthesia with propofol and the muscle relaxant rocuronium bromide was investigated. Two activation techniques, namely photic stimulation and hyperventilation, were evaluated for their potential to enhance the diagnostic validity of these recordings. Sixty-one dogs suffering from idiopathic epilepsy and 28 dogs suffering from symptomatic epilepsy were included. Electroencephalograms were recorded using five subdermal EEG electrodes (F3, F4, Cz, O1 and O2). All 89 EEGs were analysed visually and 61 were also evaluated quantitatively with fast Fourier transformation. Interictal paroxysmal epileptiform activity was found in 25% of idiopathic and in 29% of symptomatic epileptic dogs. Quantitative analysis of the EEGs (qEEGs) detected significant differences of frequency analysis in single reading points without any continuous changes of frequency bands. A comparison between healthy and affected brain hemispheres in seven dogs with focal lesions of one hemisphere did not show any significant differences in qEEG analysis. qEEG was not more sensitive than visual evaluation. Despite the use of activation techniques, the results showed that short time EEG recordings in epileptic dogs can detect interictal epileptic activity in less than one third of all seizuring dogs and is not a useful screening method.

Evaluation of periodic electrodiagnostic measurements to monitor motor recovery after different peripheral nerve lesions in the rat.

INTRODUCTION: The advantage of minimally invasive electrodiagnostic methods for periodic evaluation of reinnervation at predefined time intervals does not seem to be widely recognized. In this study, using a rat model, we assessed the utility of periodic electrodiagnostic measurements for monitoring ongoing motor recovery after peripheral nerve injuries of differing severity. METHODS: In a comparative study, either unilateral sciatic nerve crush injury (n = 10), end-to-end coaptation (n = 5), or 10-mm nerve autotransplantation (n = 10) were performed. During the 6-16-week period thereafter compound muscle action potentials (CMAPs) were recorded percutaneously every week in anesthetized animals. Motor nerve conduction velocity and percentage of axon loss were calculated and compared with footprint analyses (static sciatic index, SSI) and evaluations of sensory recovery. RESULTS: Our results clearly demonstrate that, although SSI measurements reliably demonstrated progress of regeneration after nerve crush injury only, differences in electrodiagnostically determined values precisely remodeled differences in axonal regeneration, which was confirmed by histomorphometric analysis of axonal regeneration. CONCLUSIONS: Percutaneous electrodiagnostic measurements enable reliable estimation of axonal regeneration parameters such as myelination and nerve fiber density and display in close proximity the actual status of axonal regeneration.

Potassium-aggravated muscle stiffness in 12 cats.

CASE DESCRIPTION: 12 European shorthair cats (6 males and 6 females; age range, 2 months to 3 years) from 1 household were evaluated for clinical signs of recurrent and progressive muscle spasticity. Genetic relationships among the cats were suspected but were not known. CLINICAL FINDINGS: Physical examination of all cats revealed a thin to mildly emaciated body condition and signs of suppurative rhinitis. Results of neurologic evaluations revealed no abnormalities in any cats at rest, but exercise- and stress-induced episodes of muscle spasticity were observed. Results of hematologic (7/12 cats) and CSF (4) analysis, diagnostic imaging (including radiography [7] and magnetic resonance imaging [4]), electromyography (4), motor nerve conduction tests (4), screening for metabolic storage diseases (4), provocation tests via exercise in a cold (4°C [39.2°F]) environment (7), and gross pathological and histologic examination (5) revealed no abnormalities that could potentially explain the clinical signs. However, consumption of a potassium-enriched diet resulted in severe aggravation of clinical signs in 7 of 7 cats, leading to a diagnosis of potassium-aggravated muscle stiffness. TREATMENT AND OUTCOME: 5 cats were euthanized after initial examination because of poor physical condition and severe clinical signs. Spasticity in the 7 remaining cats was improved during a 6-week follow-up period as they reduced their own activity. Further investigation and treatment were declined. CLINICAL RELEVANCE: Channelopathies are rarely recognized diseases in domestic animals. In addition to conventional diagnostic evaluation methods, provocation tests in a clinical environment can be used in the assessment of channelopathies.

Spider silk constructs enhance axonal regeneration and remyelination in long nerve defects in sheep.

BACKGROUND: Surgical reapposition of peripheral nerve results in some axonal regeneration and functional recovery, but the clinical outcome in long distance nerve defects is disappointing and research continues to utilize further interventional approaches to optimize functional recovery. We describe the use of nerve constructs consisting of decellularized vein grafts filled with spider silk fibers as a guiding material to bridge a 6.0 cm tibial nerve defect in adult sheep. METHODOLOGY/PRINCIPAL FINDINGS: The nerve constructs were compared to autologous nerve grafts. Regeneration was evaluated for clinical, electrophysiological and histological outcome. Electrophysiological recordings were obtained at 6 months and 10 months post surgery in each group. Ten months later, the nerves were removed and prepared for immunostaining, electrophysiological and electron microscopy. Immunostaining for sodium channel (NaV 1.6) was used to define nodes of Ranvier on regenerated axons in combination with anti-S100 and neurofilament. Anti-S100 was used to identify Schwann cells. Axons regenerated through the constructs and were myelinated indicating migration of Schwann cells into the constructs. Nodes of Ranvier between myelin segments were observed and identified by intense sodium channel (NaV 1.6) staining on the regenerated axons. There was no significant difference in electrophysiological results between control autologous experimental and construct implantation indicating that our construct are an effective alternative to autologous nerve transplantation. CONCLUSIONS/SIGNIFICANCE: This study demonstrates that spider silk enhances Schwann cell migration, axonal regrowth and remyelination including electrophysiological recovery in a long-distance peripheral nerve gap model resulting in functional recovery. This improvement in nerve regeneration could have significant clinical implications for reconstructive nerve surgery.

Electroencephalographic recordings in dogs: Prevention of muscle artifacts and evaluation of two activation techniques in healthy individuals.

This study was performed to improve a standard anesthetic protocol for electroencephalography (EEG) in dogs and to evaluate the effect of photic stimulation and hyperventilation on the EEG of healthy dogs. Ten clinically and neurologically normal beagle dogs were anesthetized with propofol given intravenously with average doses of 7.5mg/kg for induction and 0.37mg/kg/min constant rate infusion for maintenance. Rocuronium bromide (0.4mg/kg IV) was used as a peripheral muscle relaxant in order to prevent muscle artifacts. EEGs were recorded digitally using five subdermal needle electrodes. Photic stimulation and hyperventilation were performed to evaluate two activation techniques commonly used in human EEG recording methods. Monopolar and bipolar montages were analyzed visually and quantitatively. The use of rocuronium produced muscle artifact-free EEG recordings during the given recording procedure which indicates that rocuronium is a valuable adjunct to anesthesia during EEG recording. Photic stimulation and hyperventilation did not provoke paroxysmal discharges in the EEG of healthy dogs. Analysis of quantitative EEG data showed that background activity did not differ significantly between periods with and without stimulation. This data are important basic values and will further help to compare the effects of photic stimulation and hyperventilation of healthy dogs and those suffering from epilepsy.

[Quantitative study on cultivation of canine myoblasts]. / Quantitative Untersuchungen zur Kultivierung caniner Myoblasten.

Skeletal muscle cell culture is an important tool to discover the pathogenesis of rare canine neuromuscular diseases. The aim of the current study was to improve an existing clinical protocol to extract and cultivate canine myoblasts by using different enzymes for tissue digestion. The contamination of the mixed culture with fibrocytes should be minimized, a higher number of myoblasts with a shorter lag period should be gained and the influence of transport length on the myoblast numbers should be assessed. Twenty-one muscle biopsies (n = 21) from healthy dogs were taken, mechanically trimmed, enzymatically dissociated with either Protease or Trypsin and cultured under identical conditions for 168 hours. To distinguish and quantify myoblasts and fibrocytes an immunocytochemical staining of the muscle cell specific intermediate filament desmin was performed. To analyse the influence of a transport on the samples eight biopsies were cultured with either Trypsin or Protease at the Using Protease a significant higher production and a morphological better proliferation of myoblasts (P = 0.0102) was achieved. The average percentage of myoblasts was 78.96% using Protease and 54.68% using Trypsin. The duration of the transport (1-3 days) did not result in any significant changes in total myoblast cell counts (P = 0.798). This reveals the possibility to send muscle biopsies from distant clinics to a specialised laboratory. In conclusion, the use of Protease is an improvement for cultivating canine myoblasts and provides better conditions for further investigations elucidating pathogenesis of rare neuromuscular diseases.

Genetically modified canine Schwann cells--In vitro and in vivo evaluation of their suitability for peripheral nerve tissue engineering.

After peripheral nerve injury, Schwann cells (SC) guarantee for a regeneration-promoting milieu and are crucially involved in axonal regeneration. For extended nerve defects, bridging with an autologous nerve transplant is the gold standard therapy. Artificial biohybrid nerve transplants which combine a synthetic conduit with autologous SC genetically modified to express regeneration-promoting proteins may provide an alternative therapy to autotransplantation. The dog seems to be an ideal translational animal model for new treatment strategies. In the present study, utilizing a new transfection protocol, we transplanted enhanced green fluorescent protein (EGFP)-expressing adult canine SC (cSC) into a 5mm epineural pouch in the sciatic nerve of adult rats (n=9). The epineurial pouch technique serves as proof of principle to follow the fate of the transplanted cSC for up to 14 days after surgery. Fluorescence microscopy and immunohistochemistry revealed survival and integration of EGFP-expressing cSC into the regenerating host nerve tissue. We demonstrate that transplanted cSC contribute to the formation of bands of Büngner and are located in close vicinity to growth-associated protein-43 (GAP-43) expressing regenerating nerve fibers. This provides first evidence that transplanted genetically modified Schwann cells do successfully integrate into the host tissue where they could actively contribute to the regeneration process.

[A case of a congenital high-grade hydrocephalus internus and Dandy-Walker syndrome in a black and white German Holstein calf]. / Ein Fall von angeborenem hochgradigen Hydrocephalus internus und Dandy-Walker-Syndrom bei einem schwarzbunten Kalb der Rasse Deutsche Holsteins.

A black and white female German Holstein calf showed a highly deformed cranium. The animal was not able to stand. Further findings were bilateral strabismus divergens and negative pupillary light reflexes. Magnetic resonance imaging and pathological-anatomical examination showed that the cerebrum was replaced to a high degree by the ventricle system filled with 1.5 liters of cerebrospinal fluid. The hemispheres of the cerebellum were ruptured by the dilated fourth ventricle. In addition, the vermis and pons were missing and fluid accumulation in the subarachnoidal space extending up to the first spinal cord segments was visible. Inbreeding was not detected in the 3-generation-pedigree. No other affected calves from the same parents were known at the farm. Chromosomal abnormalities could not be detected after examination of 30 metaphase spreads using a light microscope. Infections and parasitic diseases could be ruled out for this anomaly. Very rare defect alleles might have been involved in the development of these inborn defects.