Rolf Fimmers

University of Bonn, Bonn, North Rhine-Westphalia, Germany

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Publications (325)1318.3 Total impact

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    ABSTRACT: Hypomethylation of long interspersed element (LINE)-1 has been observed in tumorigenesis when using degenerate assays, which provide an average across all repeats. However, it is unknown whether individual LINE-1 loci or different CpGs within one specific LINE-1 promoter are equally affected by methylation changes. Conceivably, studying methylation changes at specific LINE-1 may be more informative than global assays for cancer diagnostics. Therefore, with the aim of mapping methylation at individual LINE-1 loci at single-CpG resolution and exploring the diagnostic potential of individual LINE-1 locus methylation, we analyzed methylation at 11 loci by pyrosequencing, next-generation bisulfite sequencing as well as global LINE-1 methylation in bladder, colon, pancreas, prostate, and stomach cancers compared to paired normal tissues and in blood samples from some of the patients compared to healthy donors. Most (72/80) tumor samples harbored significant methylation changes at at least one locus. Notably, our data revealed not only the expected hypomethylation but also hypermethylation at some loci. Specific CpGs within the LINE-1 consensus sequence appeared preferentially hypomethylated suggesting that these could act as seeds for hypomethylation. In silico analysis revealed that these CpG sites more likely faced the histones in the nucleosome. Multivariate logistic regression analysis did not reveal a significant clinical advantage of locus-specific methylation markers over global methylation markers in distinguishing tumors from normal tissues. Methylation changes at individual LINE-1 loci are heterogeneous, whereas specific CpGs within the consensus sequence appear to be more prone to hypomethylation. With a broader selection of loci, locus-specific LINE-1 methylation could become a tool for tumor detection.
    Clinical Epigenetics 12/2015; 7(1):17. DOI:10.1186/s13148-015-0051-y · 4.54 Impact Factor
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    ABSTRACT: Livestock-associated bacteria with resistance to two or more antibiotic drug classes have heightened our awareness for the consequences of antibiotic consumption and spread of resistant bacterial strains in the veterinary field. In this study we assessed the prevalence of concomitant colonization with livestock-associated methicillin-resistant Staphylococcus aureus (LA-MRSA) and enterobacteriaceae expressing extended-spectrum betalactamases (ESBL-E) in farms at the German-Dutch border region. Nasal colonization of pigs with MRSA (113/547 (20.7%)) was less frequent than rectal colonization with ESBL-E (163/540 (30.2%)). On the individual farm level MRSA correlated with ESBL-E recovery. The data further provide information on prevalence at different stages of pig production, including abattoirs, as well as in air samples and humans living and working on the farms. Notably, MRSA was detected in stable air samples of 34 out of 35 pig farms, highlighting air as an important MRSA transmission reservoir. The majority of MRSA isolates, including those from humans, displayed tetracycline resistance and spa types t011 and t034 characteristic for LA-MRSA, demonstrating transmission from pigs to humans. ESBL-E positive air samples were detected on 6 out of 35 farms but no pig-to-human transmission was found. Detection of ESBL-E, e.g. mostly Escherichia coli with CTX-M-type ESBL, was limited to these six farms. Molecular typing revealed transmission of ESBL-E within the pig compartments; however, related strains were also found on unrelated farms. Although our data suggest that acquisition of MRSA and ESBL-E might occur among pigs in the abattoirs, MRSA and ESBL-E were not detected on the carcasses. Altogether, our data define stable air (MRSA), pig compartments (ESBL-E) and abattoir waiting areas (MRSA and ESBL-E) as major hot spots for transmission of MRSA and/or ESBL-E along the pig production chain.
    PLoS ONE 09/2015; 10(9):e0138173. DOI:10.1371/journal.pone.0138173 · 3.23 Impact Factor
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    ABSTRACT: Background: The innate immune receptor RIG-I detects viral RNA within the cytosol of infected cells. Activation of RIG-I leads to the induction of antiviral cytokines, in particular type I interferon, the inhibition of a T(H)17 response as well as to the suppression of tumor growth. Therefore, RIG-I is a promising drug target for the treatment of cancer as well as multiple sclerosis. A specific ligand for RIG-I is currently in preclinical testing. The first-in-human trial will need to be carefully designed to avoid an overshooting cytokine response. Therefore, the ResI study was set up to analyze the human immune response to standard treatment with recombinant interferon-beta to establish biomarkers for safety and efficacy of the upcoming first-in-human trial investigating the RIG-I ligand. Methods/design: ResI is a single center, prospective, open label, non-randomized phase I clinical trial. Three different cohorts (20 healthy volunteers, 20 patients with RRMS and ongoing interferon-beta treatment and 10 patients starting on interferon-beta) will receive standard interferon-beta-1a therapy for nine days. The study will be conducted according to the principles of the german medicinal products act, ICH-GCP, and the Declaration of Helsinki on the phase I unit of the Institute of Clinical Chemistry and Clinical Pharmacology and in the Department of Neurology, both University Hospital Bonn. Interferon-beta-induced cytokine levels, surface marker on immune cells, mRNA- and miRNA-expression as well as psychometric response will be investigated as target variables. Discussion: The ResI study will assess biomarkers in response to interferon-β treatment to guide the dose steps within the first-in-human trial with a newly developed RIG-I ligand. Thus, ResI is a biomarker study to enhance the safety of the clinical development of a first-in-class compound. The data can additionally be used for the development of other therapies based on type I interferon induction such as TLR ligands. Moreover, it will help to understand the interferon-beta induced immune response in a controlled in vivo setting in the human system. Trial registration: ID NCT02364986.
    BMC pharmacology & toxicology 09/2015; 16(1):25. DOI:10.1186/s40360-015-0025-x
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    ABSTRACT: Colonization of livestock with bacteria resistant to antibiotics is considered as a risk for the entry of drug-resistant pathogens into the food chain. For this reason there is a need for novel concepts to address the eradication of drug-resistant commensals on farms. In the present report we evaluated the decontamination measures taken on a farm contaminated with methicillin-resistant Staphylococcus aureus (MRSA) and Enterobacteriaceae expressing extended-spectrum ß-lactamases (ESBL-E). The decontamination process preceded the conversion from piglet breeding to gilt production. Microbiological surveillance showed that the decontamination measures eliminated the MRSA and ESBL-E strains that were detected on the farm before the complete removal of pigs, cleaning and disinfection of the stable, and the construction of an additional stable meeting high quality standards. After restarting pig production, ESBL-E remained undetectable over twelve months, but MRSA was recovered from pigs and the environment within the first two days. However, spa (Staphylococcus aureus protein A) typing revealed acquisition of a MRSA strain (type t034) that had not been detected before decontamination. Interestingly, we observed that a farm worker who had been colonized with the prior MRSA strain (t2011) acquired the new strain (t034) after two months. In summary, this report demonstrates that decontamination protocols similar to those used here can lead to successful elimination of contaminating MRSA and ESBL-E in pigs and the stable environment. Nevertheless, decontamination protocols do not prevent the acquisition of new MRSA strains. Copyright © 2015, American Society for Microbiology. All Rights Reserved.
    Applied and Environmental Microbiology 09/2015; DOI:10.1128/AEM.01713-15 · 3.67 Impact Factor
  • Forensic Science International Genetics Supplement Series 09/2015; DOI:10.1016/j.fsigss.2015.09.080
  • Zeitschrift für Gastroenterologie 08/2015; 41(08). DOI:10.1055/s-0035-1555166 · 1.05 Impact Factor
  • C C Pieper · V Weis · R Fimmers · I Rajab · M Linhart · H H Schild · C P Nähle
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    ABSTRACT: Purpose: To investigate the incidence and possible risk factors of upper deep vein obstruction in patients both prior to first cardiac device implantation and before device revision. Materials and Methods: Records of asymptomatic patients undergoing contrast venography prior to implantation or revision of a cardiac device from 09/2009 to 04/2012 were reviewed. Venograms were used to determine the presence of venous obstruction. Interrelations between the incidence of venous obstruction and patient- or device-related parameters were identified using Fisher's exact test and univariate logistic regression. Multivariate logistic regression was used to identify independent predictors of venous obstruction. Results: 456 patients met the inclusion criteria (330 males, 126 females, 67.8 ± 12.9 years). 100 patients underwent first implantation, and 356 patients underwent device revision (mean time since implantation 82.5 ± 75.3 months). Venous obstruction was present in 11.0 % and 30.1 % before implantation and revision, respectively. Only presence of ventricular escape rhythm was significantly related to venous occlusion (p < 0.001) prior to first implantation. Prior to revision, significant predictors were male sex (p = 0.01), time since implantation (p < 0.0001), presence of escape rhythm (p = 0.02), compromised coagulation (p = 0.02), phenprocoumon (p = 0.005), and peripheral arterial disease (p = 0.01). Conclusion: Although several risk factors could be identified, reliable prediction of venous obstruction was not possible. Therefore, we advocate performing venography in all patients prior to device revision or upgrade to avoid complications. In cases of first device implantation, the risks associated with venography should be weighed against the surprisingly high rate of deep upper vein obstruction. Key points: • Prevalence of upper extremity deep vein obstruction is surprisingly high.• Reliable prediction of venous obstruction is not possible.• Contrast venography should be performed prior to device revision/upgrade.• Before first implantation procedure-related risks must be weighed against high obstruction rates. Citation Format: • Pieper CC, Weis V, Fimmers R et al. Venous Obstruction in Asymptomatic Patients Undergoing First Implantation or Revision of a Cardiac Pacemaker or Implantable Cardioverter-Defibrillator: A Retrospective Single Center Analysis. Fortschr Röntgenstr 2015; DOI: 10.1055/s-0035-1553351. © Georg Thieme Verlag KG Stuttgart · New York.
    RöFo - Fortschritte auf dem Gebiet der R 07/2015; DOI:10.1055/s-0035-1553351 · 1.40 Impact Factor
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    ABSTRACT: In many clinical trials on cutaneous healing, wound closure is the primary endpoint and single most important outcome parameter, making precise assessment of this time point one of utmost importance. The assessment of wound closure can be performed either by subjective clinical inspection or with a variety of methodologies anticipated to provide more objective data. The aim of this study was to examine intra- and interrater variability of blinded photographic analysis of wound closure of human partial thickness wounds, as well as the reliability of remote photographic analysis of wounds with that of direct clinical assessment. Two plastic surgeons, a dermatologist, and a maxillofacial surgeon constituted our rater panel. High-resolution images of patient wounds derived from two randomized controlled clinical trials (EU Clinical Trials Register numbers EudraCT 2009-017418-56 (registered 12 January 2010) and EudraCT 2010-019945-24 (registered 13 July 2010)) were individually assessed by the blinded, experienced study raters. The reliability of photographic image analysis was tested using intraclass and interclass correlation. The validity of photographic image analysis was correlated with clinical assessments of documented time to heal from the study centers' files. The results demonstrated that the mean intraclass correlation coefficient of all four examiners was excellent (r = 0.79; 95% confidence interval (CI), 0.61, 1.00)). The interrater correlation coefficient was good (r = 0.67; 95% CI, 0.57, 1.00)) and therefore acceptable. The agreement between remote visual assessment and clinical assessment at the time of healing was good (r = 0.64; 95% CI, 0.52, 0.76)) with an overall difference of about 1 day. Remote photographic analysis of cutaneous wounds is a feasible instrument in clinical open-label studies to evaluate time to wound closure. We found that it was a reliable method of measuring wound closure that correlated satisfactorily with clinical judgment, bolstering the potential relevance in the current era of evolving application and dependency in the field of telemedicine. EU Clinical Trials Register EudraCT numbers 2009-017418-56 (date of registration: 12 January 2010) and 2010-019945-24 (date of registration: 13 July 2010):; and
    Trials 05/2015; 16(1):235. DOI:10.1186/s13063-015-0742-x · 1.73 Impact Factor
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    ABSTRACT: &Aims: Patients with liver cirrhosis and variceal hemorrhage have a high risk of rebleeding. We performed a prospective, randomized trial to compare prevention of rebleeding in patients given small-diameter covered stent vs those given hepatic venous pressure gradient (HVPG)-based medical therapy prophylaxis. We performed an open-label study of patients with liver cirrhosis (92% Child class A or B, 70% alcoholic) treated at 10 medical centers in Germany. Patients were randomly assigned more than 5 days after variceal hemorrhage to groups given a small intrahepatic stent shunt (cTIPS, 8mm; n=90), or medical reduction of portal pressure (propranolol and isosorbide-5-mononitrate; n=95). HVPG was determined at the time patients were assigned to groups (baseline) and 2 weeks later. In the medical group, patients with adequate reduction in HVPG (responders) remained on the drugs whereas non-responders underwent only variceal band ligation. The study was closed 10 months after the last patient was assigned to a group. The primary endpoint was variceal rebleeding. Survival, safety (adverse events), and quality of life (based on the SF-36 health survey) were secondary outcome measures. A significantly smaller proportion of patients in the TIPS group had rebleeding within 2 y (7%) than the medical group (26%) (P=.002). A slightly higher proportion of patients in the TIPS group had adverse events, including encephalopathy (18% vs 8% for medical treatment, P=.05). Rebleeding occurred in 6/23 patients (26%) receiving medical treatment before hemodynamic control was possible. Per-protocol analysis showed that rebleeding occurred in a smaller proportion of the 32 responders (18%) than in non-responders who received variceal band ligation (31%) (P=.06). Fifteen patients from the medical group (16%) underwent TIPS placement during follow-up, mainly for refractory ascites. Survival time and quality of life did not differ between both randomized groups. Placement of a small-diameter cTIPS was straightforward and prevented variceal rebleeding in patients with Child A or B cirrhosis more effectively than drugs, which often required a step-by-step therapy. However, TIPS did not increase survival time or quality of life and produced slightly more adverse events. Copyright © 2015 AGA Institute. Published by Elsevier Inc. All rights reserved.
    Gastroenterology 05/2015; 149(3). DOI:10.1053/j.gastro.2015.05.011 · 16.72 Impact Factor
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    ABSTRACT: To describe the directional kinetics of the spread of geographic atrophy (GA) spread in eyes with age-related macular degeneration and foveal sparing. Prospective, noninterventional natural history study: Fundus Autofluorescence Imaging in Age-Related Macular Degeneration (FAM; identifier, NCT00393692). Participants of the FAM study exhibiting foveal sparing of GA. Eyes were examined longitudinally with fundus autofluorescence (FAF; excitation wavelength, 488 nm; emission wavelength, >500 nm) and near infrared (NIR) reflectance imaging (Spectralis HRA+OCT or HRA2; Heidelberg Engineering, Heidelberg, Germany). Areas of foveal sparing and GA were measured by 2 independent readers using a semiautomated software tool that allows for combined NIR reflectance and FAF image grading (RegionFinder; Heidelberg Engineering). A linear mixed effect model was used to model GA kinetics over time. Change of GA lesion size over time (central vs. peripheral progression). A total of 47 eyes of 36 patients (mean age, 73.8±7.5 years) met the inclusion criteria. Mean follow-up time was 25.2±16.9 months (range, 5.9-74.6 months). Interreader agreement for measurements of GA and foveal-sparing size were 0.995 and 0.946, respectively. Mean area progression of GA toward the periphery was 2.27±0.22 mm(2)/year and 0.25±0.03 mm(2)/year toward the center. Analysis of square root-transformed data revealed a 2.8-fold faster atrophy progression toward the periphery than toward the fovea. Faster atrophy progression toward the fovea correlated with faster progression toward the periphery in presence of marked interindividual differences. The results demonstrate a significantly faster centrifugal than centripetal GA spread in eyes with GA and foveal sparing. Although the underlying pathomechanisms for differential GA progression remain unknown, local factors may be operative that protect the foveal retina-retinal pigment epithelial complex. Quantification of directional spread characteristics and modeling may be useful in the design of interventional clinical trials aiming to prolong foveal survival in eyes with GA. Copyright © 2015 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.
    Ophthalmology 05/2015; 122(7). DOI:10.1016/j.ophtha.2015.03.027 · 6.14 Impact Factor
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    ABSTRACT: Background. Ivermectin (IVM) has been the drug of choice for the treatment of onchocerciasis. However, there have been reports of persistent microfilaridermia in individuals from an endemic area in Ghana after many rounds of IVM, raising concerns of sub-optimal responses (SOR) or even the emergence of drug resistance. Since it is considered risky to continue relying only on IVM to combat this phenomenon, we assessed the effect of targeting the O. volvulus Wolbachia endosymbionts with doxycycline for these SOR individuals. Methods. 167 patients, most of them with multiple rounds of IVM, were recruited in areas with IVM SOR and treated with 100mg/day doxycycline for 6 weeks. Three and 12 months after doxycycline treatment, patients took part in standard IVM treatment. Results. At 20 months post treatment 80% of living female worms from the placebo group were Wolbachia-positive, whereas only 5.1% in the doxycycline-treated group contained bacteria. Consistent with interruption of embryogenesis, none of the nodules removed from doxycycline treated patients contained Mf, and 97% of those patients were without microfilaridermia, in contrast to placebo patients who remained at pretreatment levels (p<0.001). Moreover, a significantly enhanced number of dead worms were observed after doxycycline. Conclusion. Targeting the Wolbachia in O. volvulus is effective in clearing Mf in the skin of onchocerciasis patients with persistent microfilaridermia and in enhanced killing of adult worms after repeated standard IVM treatment. Strategies can now be developed which include doxycycline to control onchocerciasis in areas where infections persist despite the frequent use of IVM.
    Clinical Infectious Diseases 05/2015; 61(4). DOI:10.1093/cid/civ363 · 8.89 Impact Factor
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    ABSTRACT: Our aim was to retrospectively evaluate the occurrence of respiratory motion artefacts in patients undergoing dynamic liver magnetic resonance (MR) either with gadoxetate disodium or gadobutrol. Two hundred and thirty liver MR studies (115 with gadobutrol, 115 with gadoxetate disodium) were analysed. Respiratory motion artefacts on dynamic 3D T1-weighted MR images (pre-contrast, arterial, venous, and late-dynamic phase) were assessed using a five-point rating scale. Severe motion was defined as a score ≥ 4. Mean motion scores were compared with the Mann-Whitney-U-test. The chi-squared-test was used for dichotomous comparisons. Mean motion scores for gadoxetate disodium and gadobutrol showed no relevant differences for each phase of the dynamic contrast series (pre-contrast: 1.85 ± 0.70 vs. 1.88 ± 0.57, arterial: 1.85 ± 0.81 vs. 1.87 ± 0.74, venous: 1.82 ± 0.67 vs. 1.74 ± 0.64, late-dynamic: 1.75 ± 0.62 vs. 1.79 ± 0.63; p = 0.469, 0.557, 0.382 and 0.843, respectively). Severe motion artefacts had a similar incidence using gadoxetate disodium and gadobutrol (11/460 [2.4 %] vs. 7/460 [1.5 %]; p = 0.341). Gadoxetate disodium is associated with equivalent motion scores compared to gadobutrol in dynamic liver MRI. In addition, both contrast agents demonstrated a comparable and acceptable rate of severe respiratory motion artefacts. • Gadobutrol and gadoxetate disodium showed comparable motion scores in dynamic phase imaging. • The incidence of severe motion artefacts was pronounced in arterial phase imaging. • Adverse respiratory side effects were not recorded in 115 examinations with gadoxetate disodium.
    European Radiology 04/2015; DOI:10.1007/s00330-015-3736-x · 4.01 Impact Factor
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    ABSTRACT: Introduction: Endoscopic lung volume reduction (ELVR) is an emerging therapy for emphysematous COPD. However, any resulting changes in lung perfusion and ventilation remain undetermined. Here, we report ELVR-mediated adaptations in lung perfusion and ventilation, as investigated by means of pulmonary scintigraphy. Methods: In this observational study, we enrolled 26 patients (64.9 ± 9.4 yrs, 57.7% male) with COPD heterogeneous emphysema undergoing ELVR with endobronchial valves (Zephyr, Pulmonx, Inc.). Mean baseline FEV1 and RV were 32.9% and 253.8% predicted, respectively. Lung scintigraphy was conducted prior to ELVR and eight weeks thereafter. Analyses of perfusion and ventilation shifts were performed and complemented by correlation analyses between paired zones. Results: After ELVR, target zone perfusion showed a mean relative reduction of 43.32% (p<0.001), which was associated with a significant decrease in target zone ventilation (p<0.001). Perfusion of the contralateral untreated zone and of the contralateral total lung exhibited significant increases post-ELVR (p = 0.002 and p = 0.005, respectively); both correlated significantly with the corresponding target zone perfusion adaptations. Likewise, changes in target zone ventilation correlated significantly with ventilatory changes in the contralateral untreated zone and the total contralateral lung (Pearson's r: -0.42, p = 0.04 and Pearson's r: -0.42, p = 0.03, respectively). These effects were observed in case of clinical responsiveness to ELVR, as assessed by changes in the six-minute walk test distance. Discussion: ELVR induces a relevant decrease in perfusion and ventilation of the treated zone with compensatory perfusional and ventilatory redistribution to the contralateral lung, primarily to the non-concordant, contralateral zone.
    PLoS ONE 03/2015; 10(3):e0118976. DOI:10.1371/journal.pone.0118976 · 3.23 Impact Factor
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    ABSTRACT: 37 million individuals are currently infected with Onchocerca volvulus (O. volvulus), a parasitic nematode that elicits various dermal manifestations and eye damage in man. Disease control is primarily based on distributing ivermectin in mass drug administration (MDA) programmes which aim at breaking transmission by eliminating microfilariae (MF), the worm's offspring. The majority of infected individuals present generalized onchocerciasis, which is characterized by hyporesponsive immune responses and high parasite burden including MF. Recently, in areas that have been part of MDA programmes, individuals have been identified that present nodules but are amicrofilaridermic (a-MF) and our previous study showed that this group has a distinct immune profile. Expanding on those findings we determined the immune responses of O. volvulus-infected individuals to a Plasmodium-derived antigen MSP-1 (merozoite surface protein-1), which is required by the parasite to enter erythrocytes. Isolated PBMCs from O. volvulus-infected individuals (164 MF+ and 46 a-MF) and non-infected volunteers from the same region (NEN), were stimulated with MSP-1 and the resulting supernatant screened for the presence of IL-5, IL-13, IFN-γ, TNF-α, IL-6, IL-17A and IL-10. These findings were then further analyzed following regression analysis using the covariates MF, ivermectin (IVM) and region. The latter referred to the Central or Ashanti regions of Ghana, which, at the time sampling, had received 8 or 1 round of MDA respectively. IL-5, IL-13 and IFN-γ responses to MSP-1 were not altered between NEN and O. volvulus-infected individuals nor were any associations revealed in the regression analysis. IL-10, IL-6 and TNF-α MSP-1 responses were, however, significantly elevated in cultures from infected individuals. Interestingly, when compared to a-MF individuals, MSP-induced IL-17A responses were significantly higher in MF+ patients. Following multivariable regression analysis these IL-10, IL-6, TNF-α and IL-17A responses were all dominantly associated with the regional covariate. Consequently, areas with a lowered infection pressure due to IVM MDA appear to influence bystander responses to Plasmodium-derived antigens in community members even if they have not regularly participated in the therapy.
    Parasites & Vectors 03/2015; 8(1). DOI:10.1186/s13071-015-0786-5 · 3.43 Impact Factor
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    ABSTRACT: Clinical observations suggest that patients with age-related macular degeneration (AMD) have vision problems, particularly in dim light conditions. Previous studies on structural-functional analysis in patients with AMD with reticular drusen (RDR) have focused on photopic sensitivity testing but have not specifically assessed scotopic function. To evaluate retinal function by scotopic and photopic microperimetry in patients with AMD and a well-demarcated area of RDR. Prospective case series in a referral center of 22 eyes from 18 patients (mean age, 74.7 years; range, 62-87 years). The study was conducted from June 1, 2014, to October 31, 2014. With the use of combined confocal scanning laser ophthalmoscopy and spectral-domain optical coherence tomography imaging, retinal areas with RDR (category 1) and no visible pathologic alterations (category 2) were identified in each eye. Scotopic and photopic microperimetry (MP-1S; Nidek Technologies) was performed using a grid with 56 stimulus points. Comparison of mean threshold sensitivities for each category for scotopic and photopic microperimetry. In all eyes, areas of category 1 showed a relative and sharply demarcated reduction of scotopic threshold values compared with areas of category 2, but only less-pronounced differences were seen for photopic testing. Statistical analysis in the 18 eyes in which the 1.0-log unit neutral density filter was applied revealed a difference of scotopic threshold values in areas of category 1 (mean, 13.5 dB [95% CI, 12.1-15.0]) vs category 2 (mean, 18.3 dB; [95% CI, 17.4-19.3] (P ≤ .001). For photopic testing, the mean threshold values were 16.8 dB (95% CI, 15.5-18.2) in category 1 and 18.4 dB (95% CI, 17.1-19.6) in category 2 (P = .03). The results of this study suggest that rod function is more severely affected than cone function in retinal areas with RDR. This differential structural-functional correlation underscores the functional relevance of RDR in patients with AMD.
    Jama Ophthalmology 03/2015; 133(6). DOI:10.1001/jamaophthalmol.2015.0477 · 3.32 Impact Factor
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    ABSTRACT: The polyphenol quercetin may prevent CVD due to its antihypertensive and vasorelaxant properties. We investigated the effects of quercetin after regular intake on blood pressure (BP) in overweight-to-obese patients with pre-hypertension and stage I hypertension. In addition, the potential mechanisms responsible for the hypothesised effect of quercetin on BP were explored. Subjects (n 70) were randomised to receive 162 mg/d quercetin from onion skin extract powder or placebo in a double-blinded, placebo-controlled cross-over trial with 6-week treatment periods separated by a 6-week washout period. Before and after the intervention, ambulatory blood pressure (ABP) and office BP were measured; urine and blood samples were collected; and endothelial function was measured by EndoPAT technology. In the total group, quercetin did not significantly affect 24 h ABP parameters and office BP. In the subgroup of hypertensives, quercetin decreased 24 h systolic BP by -3·6 mmHg (P=0·022) when compared with placebo (mean treatment difference, -3·9 mmHg; P=0·049). In addition, quercetin significantly decreased day-time and night-time systolic BP in hypertensives, but without a significant effect in inter-group comparison. In the total group and also in the subgroup of hypertensives, vasoactive biomarkers including endothelin-1, soluble endothelial-derived adhesion molecules, asymmetric dimethylarginine, angiotensin-converting enzyme activity, endothelial function, parameters of oxidation, inflammation, lipid and glucose metabolism were not affected by quercetin. In conclusion, supplementation with 162 mg/d quercetin from onion skin extract lowers ABP in patients with hypertension, suggesting a cardioprotective effect of quercetin. The mechanisms responsible for the BP-lowering effect remain unclear.
    The British journal of nutrition 02/2015; -1. DOI:10.1017/S0007114515002950 · 3.45 Impact Factor
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    ABSTRACT: Purpose To analyze choroidal thickness (CT) in eyes with geographic atrophy (GA) secondary to age-related macular degeneration (AMD) Methods A total of 72 eyes of 72 patients (mean age 75.97±7.09 years) with GA and 37 eyes of 37 healthy controls (73.89±6.19 years) were examined by confocal scanning-laser-ophthalmoscopy and enhanced depth imaging (EDI) spectral domain optical coherence tomography. CT was measured at 25 defined points in horizontal and vertical scans. GA size was determined in fundus-autofluorescence (FAF) images and GA subtypes were classified based on abnormal FAF in the perilesional zone. Results In GA, subfoveal CT (fCT) was significantly thinner as compared to controls (173.03±90.22 µm vs. 253.95±69.19 µm, p<0.001). Analysis of averaged measurements of all 25 points obtained per patient (mCT) revealed similar results (162.07±76.26 µm vs. 228.00±66.24 µm, p<0.001). Spatial differences in CT between both groups were largest superior to the fovea. Addressing "diffuse-trickling" (n=15) and "non-diffuse-trickling" (n=57) GA independently, fCT was 114.67±43.32 µm and 188.39±93.26 µm, respectively (p=0.002) both groups being significantly thinner than controls (p=0.001 for "diffuse-trickling" and p<0.001 for "non-diffuse-trickling"). Similar results were obtained for mCT, which was 110.21±29.66 µm in "diffuse-trickling", 175.72±79.02 µm in "non-diffuse-trickling" and 228.00±66.24 µm in controls. Differences were significant with p=0.002 between both GA groups and p≤0.001 towards controls for each GA group. Conclusions The results indicate that the choroid in eyes with GA is thinner compared to normal eyes of similar age. Hereby, the extent of thinning is most pronounced in a specific subtype of GA identified by FAF imaging ("diffuse trickling"). Such GA-subtype related differences in choroidal thickness may reflect heterogeneity in the pathogenesis of disease. Copyright © 2015 by Association for Research in Vision and Ophthalmology.
    Investigative Ophthalmology &amp Visual Science 01/2015; 56(2). DOI:10.1167/iovs.14-14933 · 3.40 Impact Factor
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    ABSTRACT: In patients undergoing transcatheter aortic valve implantation (TAVI), the high prevalence of periph- eral artery disease (PAD) limits femoral access and increases vascular complications that are associated with mortality and morbidity. Our study assessed the ability of a balloon-expandable large-bore vascular sheath to increase access-site availability and to reduce vascular complications. Methods and results: Among 257 patients from two centres, 43 patients underwent transfemoral TAVI with the use of the SoloPath balloon-expandable sheath due to complex iliofemoral access anatomy. Propensity score matching (2:1) was performed except for the sheath to femoral artery ratio (SFAR). Compared to stand- ard sheath patients, we found no significant difference in 30-day and one-year mortality (SoloPath vs. stand- ard sheath, 9.3% vs. 3.5%; p=0.2, and 18.6% vs. 23.3%; p=0.7), major vascular complications (9.3% vs. 4.7%; p=0.3), and major bleeding (9.3% vs. 10.5%; p=0.5) in the cohort with the balloon-expandable sheath. Conclusions: The use of a balloon-expandable large-bore sheath in patients with a high risk for vascular complications due to complex access-site anatomy proved to be feasible and safe. However, circumferential calcifications and sheath-to-artery ratios account for vascular access complications even in patients treated with the balloon-expandable sheath.
    EuroIntervention: journal of EuroPCR in collaboration with the Working Group on Interventional Cardiology of the European Society of Cardiology 01/2015; DOI:10.4244/EIJY15M01_10 · 3.77 Impact Factor
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    ABSTRACT: In adult and pediatric cardiology, n-terminal pro-B-type natriuretic peptide (nt-proBNP) serves as biomarker in the diagnosis and management of cardiovascular dysfunction. Elevated levels of circulating nt-proBNP are present in fetal conditions associated with myocardial pressure or volume load. Compared to fetal blood sampling, amniocentesis is technically easier and can be performed from early pregnancy onwards. We aimed to investigate amniotic fluid (AF) nt-proBNP concentrations in normal pregnancies between 10 and 34 weeks of gestation. Nt-proBNP and total protein (TP) was measured in AF by chemiluminescence assay (photometry, respectively). To adjust for a potential dilutional effect, the AF-nt-proBNP/AF-TP ratio was analyzed. Reference intervals were constructed by regression modeling across gestational age. 132 samples were analyzed. A negative correlation between AF-nt-proBNP/AF-TP ratio and gestational age was observed. Curves for the mean and the 5% and 95% reference interval between 10 and 34 weeks of gestation were established. In normal pregnancy, nt-proBNP is present in AF and decreases during gestation. Our data provide the basis for research on AF-nt-proBNP as biomarker in fetal medicine.
    PLoS ONE 12/2014; 9(12):e114416. DOI:10.1371/journal.pone.0114416 · 3.23 Impact Factor
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    ABSTRACT: Abstract Vascular endothelial cadherin and β-catenin play a key role in establishment and maintenance of the endothelial monolayer integrity, regulation of vascular barrier function, and initiation of angiogenesis. The cadherin-catenin complex has been shown to be reduced in Type 1 diabetic placenta, but the exact relationship between histopathologic findings and clinical data is not known. Immunohistochemistryof placental tissue from Type 1, Type 2 and gestational diabetes showed, that diabetes per se might be compatible with normal levels of vascular endothelial cadherin and β-catenin in fetoplacental vessels as long as the patient has not been treated with insulin. Immunoreactivity of VE-cadherin did correlate poorly with maternal glycaemic control as was investigated in this study by birthweight, body-mass-index, and HbA1c. There was no correlation found between the immunoreactivity of β-catenin and birthweight, body-mass-index, and HbA1c. However our data did show a storng correlation immunoreactivity and whether or not the patient had been treated with insulin or not. Therefore patients diagnosed with gestational diabetes, who had not been treated with insulin, had similar levels of VE-cadherin and β-catenin as the control group, thus indicating that diabetes per se must not necessarily lead to a reduction. Our study suggests that therapeutic intervention using insulin in pregnancies complicated by diabetes might have potentially harmful effects on placental morphology. Future studies should further investigate these findings.
    Pediatric and Developmental Pathology 10/2014; 18(1). DOI:10.2350/13-11-1400-OA.1 · 0.87 Impact Factor

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8k Citations
1,318.30 Total Impact Points


  • 1989–2015
    • University of Bonn
      • • Institute of Human Genetics
      • • Medizinische Klinik und Poliklinik II
      • • Institute of Biomedical Statistics, Computer Science and Epidemiology
      • • Zentrum für Innere Medizin
      • • Medizinische Klinik und Poliklinik I
      • • Department of Neurobiology
      Bonn, North Rhine-Westphalia, Germany
  • 2006–2014
    • Deutsche Gesellschaft für Medizinische Informatik, Biometrie und Epidemiologie e.V.
      Bonn, North Rhine-Westphalia, Germany
  • 1994–2014
    • University of Bonn - Medical Center
      • Institute for Clinical Chemistry and Clinical Pharmacology
      Bonn, North Rhine-Westphalia, Germany
  • 2012
    • Chung-Ang University
      Sŏul, Seoul, South Korea
  • 2008
    • Universitätsklinikum Jena
      Jena, Thuringia, Germany
  • 1994–2004
    • University of Cologne
      Köln, North Rhine-Westphalia, Germany
  • 2002
    • Johannes Gutenberg-Universität Mainz
      • I. Department of Medicine
      Mayence, Rheinland-Pfalz, Germany
  • 1998–2002
    • Sigmund-Freud-Institut
      Frankfurt, Hesse, Germany
  • 1999
    • University of Freiburg
      Freiburg, Baden-Württemberg, Germany
  • 1997
    • Hebrew University of Jerusalem
      Yerushalayim, Jerusalem, Israel