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Dive into the research topics where Barbara Fiedler is active.

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Featured researches published by Barbara Fiedler.


Circulation | 2010

Impact of Thrombophilia on Risk of Arterial Ischemic Stroke or Cerebral Sinovenous Thrombosis in Neonates and Children A Systematic Review and Meta-Analysis of Observational Studies

Gili Kenet; Lisa K. Lütkhoff; Manuela Albisetti; Timothy J. Bernard; Mariana Bonduel; Stéphane Chabrier; Anthony K.C. Chan; Gabrielle deVeber; Barbara Fiedler; Heather J. Fullerton; Neil A. Goldenberg; Eric F. Grabowski; Gudrun Günther; Christine Heller; Susanne Holzhauer; Alfonso Iorio; Janna M. Journeycake; Ralf Junker; Fenella J. Kirkham; Karin Kurnik; John K. Lynch; Christoph Male; Marilyn J. Manco-Johnson; Rolf M. Mesters; Paul Monagle; C. Heleen van Ommen; Leslie Raffini; Kevin Rostasy; Paolo Simioni; Ronald Sträter

Background— The aim of this study was to estimate the impact of thrombophilia on risk of first childhood stroke through a meta-analysis of published observational studies. Methods and Results— A systematic search of electronic databases (Medline via PubMed, EMBASE, OVID, Web of Science, The Cochrane Library) for studies published from 1970 to 2009 was conducted. Data on year of publication, study design, country of origin, number of patients/control subjects, ethnicity, stroke type (arterial ischemic stroke [AIS], cerebral venous sinus thrombosis [CSVT]) were abstracted. Publication bias indicator and heterogeneity across studies were evaluated, and summary odds ratios (ORs) and 95% confidence intervals (CIs) were calculated with fixed-effects or random-effects models. Twenty-two of 185 references met inclusion criteria. Thus, 1764 patients (arterial ischemic stroke [AIS], 1526; cerebral sinus venous thrombosis [CSVT], 238) and 2799 control subjects (neonate to 18 years of age) were enrolled. No significant heterogeneity was discerned across studies, and no publication bias was detected. A statistically significant association with first stroke was demonstrated for each thrombophilia trait evaluated, with no difference found between AIS and CSVT. Summary ORs (fixed-effects model) were as follows: antithrombin deficiency, 7.06 (95% CI, 2.44 to 22.42); protein C deficiency, 8.76 (95% CI, 4.53 to 16.96); protein S deficiency, 3.20 (95% CI, 1.22 to 8.40), factor V G1691A, 3.26 (95% CI, 2.59 to 4.10); factor II G20210A, 2.43 (95% CI, 1.67 to 3.51); MTHFR C677T (AIS), 1.58 (95% CI, 1.20 to 2.08); antiphospholipid antibodies (AIS), 6.95 (95% CI, 3.67 to 13.14); elevated lipoprotein(a), 6.27 (95% CI, 4.52 to 8.69), and combined thrombophilias, 11.86 (95% CI, 5.93 to 23.73). In the 6 exclusively perinatal AIS studies, summary ORs were as follows: factor V, 3.56 (95% CI, 2.29 to 5.53); and factor II, 2.02 (95% CI, 1.02 to 3.99). Conclusions— The present meta-analysis indicates that thrombophilias serve as risk factors for incident stroke. However, the impact of thrombophilias on outcome and recurrence risk needs to be further investigated.


Journal of Child Neurology | 2008

Brain tumors in children: initial symptoms and their influence on the time span between symptom onset and diagnosis.

Bettina C. Reulecke; Christian G. Erker; Barbara Fiedler; Thomas-Ulrich Niederstadt; Gerhard Kurlemann

Brain tumors are the most common solid tumor entity in childhood. Symptoms are often unspecific, depending not only on the localization of the tumor, but also on the age of the child. The aim of this study was to detect factors influencing the time span between the occurrence of symptoms and the diagnosis to alert health professionals to the early symptoms of pediatric brain tumors. The records of 245 consecutive patients treated for brain tumors between 1980 and 2004 at the neuropediatric department of the University of Muenster were analyzed regarding their primary symptoms, tumor location, entity, and, in 151 cases, the primary electroencephalogram findings. The median time span between symptom onset and diagnosis in our study was 24 days. Multivariate analysis showed a significant influence of 6 parameters on the interval between symptom onset and diagnosis. An additional symptom had a significant influence on the time span between symptom onset and diagnosis in the univariate analysis. The findings that several symptoms influence the interval between symptom onset and diagnosis emphasize the necessity to systematically inquire about the key symptoms of brain tumors. The challenge for every consultant is to decide in which cases cerebral imaging is appropriate. As the most frequent symptoms are unspecific and often underestimated, a detailed anamnesis is crucial to detect possible brain tumor patients. In doubtful cases, a systematic interrogation regarding the catalogue of symptoms can be helpful.


American Journal of Human Genetics | 2015

SLC39A8 Deficiency: A Disorder of Manganese Transport and Glycosylation

Julien H. Park; Max Hogrebe; Marianne Grüneberg; Ingrid DuChesne; Ava L. von der Heiden; Janine Reunert; Karl P. Schlingmann; Kym M. Boycott; Chandree L. Beaulieu; Aziz Mhanni; A. Micheil Innes; Konstanze Hörtnagel; Saskia Biskup; Eva M. Gleixner; Gerhard Kurlemann; Barbara Fiedler; Heymut Omran; Frank Rutsch; Yoshinao Wada; Konstantinos Tsiakas; René Santer; Daniel W. Nebert; Stephan Rust; Thorsten Marquardt

SLC39A8 is a membrane transporter responsible for manganese uptake into the cell. Via whole-exome sequencing, we studied a child that presented with cranial asymmetry, severe infantile spasms with hypsarrhythmia, and dysproportionate dwarfism. Analysis of transferrin glycosylation revealed severe dysglycosylation corresponding to a type II congenital disorder of glycosylation (CDG) and the blood manganese levels were below the detection limit. The variants c.112G>C (p.Gly38Arg) and c.1019T>A (p.Ile340Asn) were identified in SLC39A8. A second individual with the variants c.97G>A (p.Val33Met) and c.1004G>C (p.Ser335Thr) on the paternal allele and c.610G>T (p.Gly204Cys) on the maternal allele was identified among a group of unresolved case subjects with CDG. These data demonstrate that variants in SLC39A8 impair the function of manganese-dependent enzymes, most notably β-1,4-galactosyltransferase, a Golgi enzyme essential for biosynthesis of the carbohydrate part of glycoproteins. Impaired galactosylation leads to a severe disorder with deformed skull, severe seizures, short limbs, profound psychomotor retardation, and hearing loss. Oral galactose supplementation is a treatment option and results in complete normalization of glycosylation. SLC39A8 deficiency links a trace element deficiency with inherited glycosylation disorders.


Journal of Pineal Research | 2002

Spontaneous central melatonin secretion and resorption kinetics of exogenous melatonin: a ventricular CSF study.

Otfried Debus; Alexander Lerchl; Hans W. Bothe; Janbernd Bremer; Barbara Fiedler; Meike Franssen; Jessica Koehring; Michaela Steils; Gerhard Kurlemann

Abstract: Pineal secretion of melatonin, a potential sleep‐inducing agent, is stimulated by nighttime darkness. To gain better insight into the control of melatonin physiology in man, we studied melatonin concentrations in ventricular cerebrospinal fluid (v‐CSF). In four patients aged 1–4 yr with therapeutic v‐CSF drainage, including one with lumbar CSF (l‐CSF) drainage, CSF samples were collected sequentially over 24‐hr periods. One further patient with severe sleep disturbance had one collection period under chloral hydrate and another after oral melatonin administration. Reduction of light intensity or night periods, respectively, led to increased melatonin levels. At the moment of falling asleep, additional melatonin peaks were observed in v‐CSF but not in l‐CSF. Oral melatonin, but not chloral hydrate, caused a rapid increase in CSF melatonin between 10 and 80 min after intake, raising levels far beyond physiological concentrations. The commencement of sleep is associated with an additional melatonin peak v‐CSF which is independent of baseline secretion during the day–night cycle. The possibility is discussed that the induction of sleep might depend on a critical level or increased melatonin concentrations, which can be achieved with orally administered melatonin.


Genetics in Medicine | 2018

SLC39A8 deficiency: biochemical correction and major clinical improvement by manganese therapy

Julien H. Park; Max Hogrebe; Manfred Fobker; Renate Brackmann; Barbara Fiedler; Janine Reunert; Stephan Rust; Konstantinos Tsiakas; René Santer; Marianne Grüneberg; Thorsten Marquardt

PurposeSLC39A8 deficiency is a severe inborn error of metabolism that is caused by impaired function of manganese metabolism in humans. Mutations in SLC39A8 lead to impaired function of the manganese transporter ZIP8 and thus manganese deficiency. Due to the important role of Mn2+ as a cofactor for a variety of enzymes, the resulting phenotype is complex and severe. The manganese-dependence of β-1,4-galactosyltransferases leads to secondary hypoglycosylation, making SLC39A8 deficiency both a disorder of trace element metabolism and a congenital disorder of glycosylation. Some hypoglycosylation disorders have previously been treated with galactose administration. The development of an effective treatment of the disorder by high-dose manganese substitution aims at correcting biochemical, and hopefully, clinical abnormalities.MethodsTwo SCL39A8 deficient patients were treated with 15 and 20 mg MnSO4/kg bodyweight per day. Glycosylation and blood manganese were monitored closely. In addition, magnetic resonance imaging was performed to detect potential toxic effects of manganese.ResultsAll measured enzyme dysfunctions resolved completely and considerable clinical improvement regarding motor abilities, hearing, and other neurological manifestations was observed.ConclusionHigh-dose manganese substitution was effective in two patients with SLC39A8 deficiency. Close therapy monitoring by glycosylation assays and blood manganese measurements is necessary to prevent manganese toxicity.


Neonatal and Pediatric Medicine | 2017

Prediction of Multiple Sclerosis after Childhood Isolated Optic Neuritis

Christiane Elpers; Amler S; Grenzebach U; Allkemper T; Barbara Fiedler; Schwartz O; Sven G. Meuth; Gerhard Kurlemann

Isolated optic neuritis in adults (ON) is the most common initial manifestation of multiple sclerosis (MS). Conversion to MS after childhood ON is not well determined. We aimed to identify risk factors predicting MS following ON and to develop risk profiles with adjusted clinical follow-up based on current diagnostic tools. Medical records of 42 cases with isolated ON between 1970 and 2005 were analysed. In 2006 and 2007 all patients received a clinical follow-up investigation including ophthalmological and neurological examination, visual evoked potentials (VEPs), somatosensory evoked potentials (SEPs) and cerebral magnetic resonance imaging (cMRI). Investigation was performed to a mean follow-up of 18 years (3-38 years). 14% of all patients showed MS-like lesions in cMRI. Additional neurologic symptoms or abnormal cMRI at initial presentation indicating dissemination in space significantly altered the risk of MS (OR 16.0, 95% CI [1.5; 176.5], p = 0.020), (OR 4.6, 95% CI [0.7; 31.0], respectively). Severe visual loss and funduscopic affection reduced the likelihood for progression to MS (OR 0.2, 95% CI [0.0; 1.5]). Children presenting with isolated ON, neurological impairment at onset or especially coordinative dysfunction at follow-up and demyelinating lesions in cMRI at disease onset were at high risk for the development of MS.


Neuropediatrics | 2015

A Case Report on Juvenile Neuromyelitis Optica: Early Onset, Long Remission Period, and Atypical Treatment Response

C. Elpers; Catharina C. Gross; Barbara Fiedler; Sven G. Meuth; Gerhard Kurlemann

Neuromyelitis optica (NMO) is a severe inflammatory demyelinating disease of the central nervous system and preferentially targets the optic nerves and spinal cord. NMO is rare in children and clinical course of the disease is highly variable as described in studies. Here, we present a case report of a young girl presenting with a rare course of pediatric NMO with an early disease onset at the age of 12 years, a relapse free interval of 4 years, evidence of NMO immunoglobulin G (IgG) and an unusual response against immunosuppressive therapy. The aim of this report is to highlight the potentially long remission period between relapses complicating proper diagnosis despite well defined diagnostic criteria. In addition, we want to encourage the use of rituximab in pediatric NMO, although larger cohorts are warranted to establish B cell depleting therapies in juvenile NMO.


F1000Research | 2010

Impact of thrombophilia on arterial ischemic stroke or cerebral venous sinus thromboses in children: a systematic review & meta-analysis of observational studies

Lisa K. Lütkhoff; Manuela Albisetti; Timothy J. Bernard; Mariana Bonduel; Stéphane Chabrier; Anthony T.C. Chan; Barbara Fiedler; Heather J. Fullerton; Vijeja Ganesan; Neil A. Goldenberg; Meredith R. Golomb; Eric F. Grabowski; Christine Heller; Susanne Holzhauer; Alfonso Iorio; Janna M. Journeycake; Gili Kenet; Fenella J. Kirkham; Karin Kurnik; John K. Lynch; Christoph Male; Marilyn J. Manco-Johnson; Rolf M. Mesters; Paul Monagle; Heleen van Ommen; Leslie Raffini; Paolo Simioni; Ronald Straeter; Guy Young; Ulrike Nowak-Göttl

Background: The incidence of stroke in children is estimated at about 2.6 per 100,000 per year. Apart from acquired thrombophilic risk factors, such as the presence of antiphospholipid antibodies, inherited thrombophilias (IT) have been found to be associated with stroke in infants and children. However, results of single studies on the risk of stroke onset associated with IT have been contradictory or inconclusive, mainly due to lack of statistical power. The aim of this study was to estimate the impact of IT on risk of childhood stroke via meta-analysis of published observational studies. In addition, forest plots for FV G1691A (figure 2a & b) for older infants (a), and children compared to neonates (b) with TE are shown.


Blood | 2009

Impact of Thrombophilia On Arterial Ischemic Stroke or Cerebral Venous Sinus Thromboses in Children : A Systematic Review & Meta-Analysis of Observational Studies

Lisa K. Luetkhoff; Manuela Albisetti; Timothy J. Bernard; Mariana Bonduel; Stephanie Chabrier; Anthony K.C. Chan; Barbara Fiedler; Heather J. Fullerton; Vijeja Ganesan; Neil A. Goldenberg; Meredith R. Golomb; Eric F. Grabowski; Christine Heller; Susanne Holzhauer; Alfonso Iorio; Janna M. Journeycake; Gili Kenet; Fenella J. Kirkham; Karin Kurnik; John K. Lynch; Christoph Male; Marilyn J. Manco-Johnson; Rolf M. Mesters; Paul Monagle; Heleen van Ommen; Leslie Raffini; Paolo Simioni; Ronald Straeter; Guy Young; Ulrike Nowak-Göttl


Archive | 2013

Case Report A bumpy road to the diagnosis of a Kytococcus schroeteri shunt infection

Frieder Schaumburg; Christian Schmalstieg; Barbara Fiedler; Angela Brentrup; Heymut Omran; Karsten Becker

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Christine Heller

Goethe University Frankfurt

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Janna M. Journeycake

University of Texas Southwestern Medical Center

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John K. Lynch

National Institutes of Health

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Leslie Raffini

Children's Hospital of Philadelphia

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Manuela Albisetti

Boston Children's Hospital

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