Susanna Nikolaus

University Medical Center Schleswig-Holstein, Kiel, Schleswig-Holstein, Germany

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Publications (99)956.97 Total impact

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    ABSTRACT: Diet is related to many chronic disease conditions such as the metabolic syndrome (MetS). We set out to compare behaviour-related with disease-related patterns and their association with the MetS in a German cross-sectional study. A total of 905 participants of a Northern German cohort (aged 25-82 years) completed a FFQ, underwent anthropometric assessments and provided a blood sample. Dietary patterns were derived by principal component analysis (PCA) and reduced-rank regression (RRR) from forty-two food groups. Components of the MetS were used as response variables for the RRR analysis. Simplified patterns comprising ten food groups were generated. Logistic regression analysis was performed to evaluate the likelihood of having the MetS across the quartiles of simplified pattern scores. We identified two similar dietary patterns derived by PCA and RRR characterised by high intakes of potatoes, various vegetables, red and processed meat, fats, sauce and bouillon. Comparing simplified patterns, an increased RRR pattern score was associated with a higher OR (2·18, 95 % CI 1·25, 3·81) of having the MetS than an increased PCA pattern score (OR 1·92, 95 % CI 1·21, 3·03). Comparing concordant food groups by both dietary pattern methods, a diet high in legumes, beef, processed meat and bouillon was also positively associated with the prevalence of the MetS after adjustment for potential confounders (OR 1·71, 95 % CI 1·04, 2·79). We identified a behaviour-related pattern that was positively associated with the MetS. The application of both dietary pattern methods may be advantageous to obtain information for designing and realising dietary guidelines. Prospective studies are needed to confirm the results.
    British Journal Of Nutrition 10/2014; 112(8):1364-1372. · 3.30 Impact Factor
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    ABSTRACT: To detect high risk patients with a progressive disease course of ulcerative colitis (UC) requiring immunosuppressive therapy (IT).
    World journal of gastroenterology : WJG. 09/2014; 20(35):12574-80.
  • S Schreiber, S Nikolaus, P Rosenstiel
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    ABSTRACT: The complex microbiome of the human gut contains an excessive amount of genetic information that is more than 100-fold larger than the human genome. In patients with inflammatory bowel disease diversity of the gut microbiome is significantly reduced and moreover specific phyla are overrepresented or underrepresented. However, the functional capacity of the microflora to generate certain metabolic products containing lipids or amino acids- and more complex regulatory substances is more important that the mere annotation of the microorganisms. Modern pharmacological approaches target the functional capacity and constitution of the microbiome. An important strategy is the development of controlled release formulations that deliver defined lipid, carbohydrate or amino acid products derived from nutritional components targeting gut areas distal to the absorption zones of the upper gastrointestinal tract.
    Der Internist 07/2014; · 0.33 Impact Factor
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    ABSTRACT: Diagnosis of inflammatory bowel disease (IBD) is based on clinical presentation, colonoscopy and histology. Differentiation of Crohn's disease (CD) and ulcerative colitis (UC) can be difficult in some patients. Endoscopic ultrasound (EUS) provides high resolution images of the gastrointestinal wall (GI) and may be an alternative to differentiate CD/UC. EUS of the GI layers in patients with IBD and healthy controls (HC) for the differential diagnosis of UC/CD in a prospective, blinded study. Consecutive patients with CD, UC or HC underwent EUS in the mid sigmoid colon with a forward-viewing radial echoendoscope. Mucosal, submucosal, total wall thickness (TWT) and locoregional lymphnodes (LN) were assessed by EUS in a blinded fashion. TWT was correlated with macroscopic IBD scores and histological inflammation scores. Total wall thickness of 61 HC was 1.71 ± 0.02 mm, and 3.51 ± 0.15 mm in n = 52 with active IBD. In patients with active UC significant thickening of the mucosa was observed but nearly normal submucosa and m.propria. In active CD significant thickening of the submucosal layer was seen with nearly normal mucosa and m.propria [MucosaUC = 2.08 ± 0.11 mm, MucosaCD = 1.32 ± 0.17 mm (P = 0.0001); SubmucosaUC = 1.01 ± 0.08 mm, SubmucosaCD = 2.01 ± 0.22 mm (P = 0.0001)]. In 73.7% of patients with active CD, but in none with UC, paracolonic lymph nodes were detected. When mucosal-submucosal and TWT and LNs were combined, the sensitivity was 92.3% for the differentiation of active UC/CD. There was a strong correlation of TWT with histological inflammation scores (UC: r = 0.43; CD: r = 0.69). Increased total wall thickness has a high positive predictive value for active IBD. EUS can differentiate active UC from CD and quantify the level of colonic inflammation.
    Alimentary Pharmacology & Therapeutics 02/2014; · 4.55 Impact Factor
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    ABSTRACT: BACKGROUND& AIMS: Genome-wide association studies (GWASs) have identified 140 Crohn's disease (CD) susceptibility loci. For most loci, the variants that cause disease are not known and the genes affected by these variants have not been identified. We aimed to identify variants that cause CD through detailed sequencing, genetic association, expression, and functional studies. METHODS: We sequenced whole exomes of 42 unrelated subjects with Crohn's disease (CD) and 5 healthy individuals (controls), and then filtered single-nucleotide variants by incorporating association results from meta-analyses of CD GWASs and in silico mutation effect prediction algorithms. We then genotyped 9348 patients with CD, 2868 with ulcerative colitis, and 14,567 controls, and associated variants analyzed in functional studies using materials from patients and controls and in vitro model systems. RESULTS: We identified rare missense mutations in PR domain-containing1 (PRDM1) and associated these with CD. These increased proliferation of T cells and secretion of cytokines upon activation, and increased expression of the adhesion molecule L-selectin. A common CD risk allele, identified in GWASs, correlated with reduced expression of PRDM1 in ileal biopsies and peripheral blood mononuclear cells (combined P=1.6×0(-8)). We identified an association between CD and a common missense variant, Val248Ala, in nuclear domain 10 protein 52 (NDP52) (P=4.83×10(-9)). We found that this variant impairs the regulatory functions of NDP52 to inhibit NFκB activation of genes that regulate inflammation and affect stability of proteins in toll-like receptor pathways. CONCLUSIONS: We have extended GWAS results and provide evidence that variants in PRDM1 and NDP52 determine susceptibility to CD. PRDM1 maps adjacent to a CD interval identified in GWASs and encodes a transcription factor expressed by T and B cells. NDP52 is an adaptor protein that functions in selective autophagy of intracellular bacteria and signaling molecules, supporting the role for autophagy in pathogenesis of CD.
    Gastroenterology 04/2013; · 12.82 Impact Factor
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    ABSTRACT: To date, liver biopsy is the only means of reliable diagnosis for fatty liver disease (FLD). Owing to the inevitable biopsy-associated health risks, however, the development of valid noninvasive diagnostic tools for FLD is well warranted. We evaluated a particular metabolic profile with regard to its ability to diagnose FLD and compared its performance to that of established phenotypes, conventional biomarkers and disease-associated genotypes. The study population comprised 115 patients with ultrasound-diagnosed FLD and 115 sex- and age-matched controls for whom the serum concentration was measured of 138 different metabolites, including acylcarnitines, amino acids, biogenic amines, hexose, phosphatidylcholines (PCs), lyso-PCs and sphingomyelins. Established phenotypes, biomarkers, disease-associated genotypes and metabolite data were included in diagnostic models for FLD using logistic regression and partial least-squares discriminant analysis. The discriminative power of the ensuing models was compared with respect to area under curve (AUC), integrated discrimination improvement (IDI) and by way of cross-validation (CV). Use of metabolic markers for predicting FLD showed the best performance among all considered types of markers, yielding an AUC of 0.8993. Additional information on phenotypes, conventional biomarkers or genotypes did not significantly improve this performance. Phospholipids and branched-chain amino acids were most informative for predicting FLD. We show that the inclusion of metabolite data may substantially increase the power to diagnose FLD over that of models based solely upon phenotypes and conventional biomarkers.
    PLoS ONE 01/2013; 8(10):e76813. · 3.53 Impact Factor
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    ABSTRACT: BACKGROUND & AIMS: Genome-wide association studies (GWAS) have identified 140 Crohn's disease (CD) susceptibility loci. For most loci, the variants that cause disease are not known and the genes affected by these variants have not been identified. We aimed to identify variants that cause CD through detailed sequencing, genetic association, expression, and functional studies. METHODS: We sequenced whole exomes of 42 unrelated subjects with CD and 5 healthy subjects (controls) and then filtered single nucleotide variants by incorporating association results from meta-analyses of CD GWAS and in silico mutation effect prediction algorithms. We then genotyped 9348 subjects with CD, 2868 subjects with ulcerative colitis, and 14,567 control subjects and associated variants analyzed in functional studies using materials from subjects and controls and in vitro model systems. RESULTS: We identified rare missense mutations in PR domain-containing 1 (PRDM1) and associated these with CD. These mutations increased proliferation of T cells and secretion of cytokines on activation and increased expression of the adhesion molecule L-selectin. A common CD risk allele, identified in GWAS, correlated with reduced expression of PRDM1 in ileal biopsy specimens and peripheral blood mononuclear cells (combined P = 1.6 × 10(-8)). We identified an association between CD and a common missense variant, Val248Ala, in nuclear domain 10 protein 52 (NDP52) (P = 4.83 × 10(-9)). We found that this variant impairs the regulatory functions of NDP52 to inhibit nuclear factor κB activation of genes that regulate inflammation and affect the stability of proteins in Toll-like receptor pathways. CONCLUSIONS: We have extended the results of GWAS and provide evidence that variants in PRDM1 and NDP52 determine susceptibility to CD. PRDM1 maps adjacent to a CD interval identified in GWAS and encodes a transcription factor expressed by T and B cells. NDP52 is an adaptor protein that functions in selective autophagy of intracellular bacteria and signaling molecules, supporting the role of autophagy in the pathogenesis of CD.
    Gastroenterology 01/2013; 145(2):339-47. · 12.82 Impact Factor
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    ABSTRACT: OBJECTIVE: Mechanisms of action (MoA) of anti-tumour necrosis factor α (TNFα) therapies in Crohn's disease (CD) may critically involve induction of immune cell apoptosis via membrane-bound TNFα (mTNFα) binding. Certolizumab pegol (CZP), which is effective in induction and maintenance of remission in CD lacks the ability to induce apoptosis. The aim of this study was to analyse transcriptomal responses of reverse signalling induced by the TNFα binding agents infliximab (IFX) and CZP in myelomonocytic cells. DESIGN: Induction of transcriptional patterns upon anti-TNFα stimulation was assessed using oligonucleotide microarrays. mRNA expression of GDF-1/ LASS1, which was identified as a shared target, was studied in inflammatory bowel disease by real-time PCR, while signalling pathways induced by growth and differentiation factor 1 (GDF-1) were investigated using western blots and ELISA. RESULTS: IFX and CZP induced a common signature of 20 transcripts that could be categorised into control of cell cycle, transcription activation and pre-mRNA processing. We selected GDF-1/LASS1 for functional follow-up, which was found to be upregulated in inflamed CD tissues. We show that downregulation of GDF-1/LASS1 depends on autocrine release of transforming growth factor β after mTNFα ligation. We demonstrate that GDF-1 itself acts as a novel proinflammatory factor via induction of interleukin 6 and signal transducer and activator of transcription 3 and is downregulated after IFX treatment. CONCLUSION: Commonalities in the MoA of IFX and CZP comprise modulation of non-apoptotic pathways through downregulation of proinflammatory GDF-1. Further characterisation of the molecular role of GDF-1 in complex inflammatory processes in vivo is warranted to decide whether this proinflammatory molecule is a promising therapeutic target in patients with CD.
    Gut 04/2012; · 10.73 Impact Factor
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    ABSTRACT: Psoriasis (PS) and Crohn disease (CD) have been shown to be epidemiologically, pathologically, and therapeutically connected, but little is known about their shared genetic causes. We performed meta-analyses of five published genome-wide association studies on PS (2,529 cases and 4,955 controls) and CD (2,142 cases and 5,505 controls), followed up 20 loci that showed strongest evidence for shared disease association and, furthermore, tested cross-disease associations for previously reported PS and CD risk alleles in additional 6,115 PS cases, 4,073 CD cases, and 10,100 controls. We identified seven susceptibility loci outside the human leukocyte antigen region (9p24 near JAK2, 10q22 at ZMIZ1, 11q13 near PRDX5, 16p13 near SOCS1, 17q21 at STAT3, 19p13 near FUT2, and 22q11 at YDJC) shared between PS and CD with genome-wide significance (p < 5 × 10(-8)) and confirmed four already established PS and CD risk loci (IL23R, IL12B, REL, and TYK2). Three of the shared loci are also genome-wide significantly associated with PS alone (10q22 at ZMIZ1, p(rs1250544) = 3.53 × 10(-8), 11q13 near PRDX5, p(rs694739) = 3.71 × 10(-09), 22q11 at YDJC, p(rs181359) = 8.02 × 10(-10)). In addition, we identified one susceptibility locus for CD (16p13 near SOCS1, p(rs4780355) = 4.99 × 10(-8)). Refinement of association signals identified shared genome-wide significant associations for exonic SNPs at 10q22 (ZMIZ1) and in silico expression quantitative trait locus analyses revealed that the associations at ZMIZ1 and near SOCS1 have a potential functional effect on gene expression. Our results show the usefulness of joint analyses of clinically distinct immune-mediated diseases and enlarge the map of shared genetic risk loci.
    The American Journal of Human Genetics 04/2012; 90(4):636-47. · 11.20 Impact Factor
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    ABSTRACT: Genetic variation in NOD2 and cigarette smoking are well-established risk factors for the development of Crohn's disease (CD). However, little is known about a potential interaction between these risk factors. We investigated gene-environment interactions between CD-associated NOD2 alleles and cigarette smoking in a large sample of patients with CD. Three previously reported CD-associated variants in NOD2 (R702W, G908R, 1007fs) were genotyped in 1636 patients with CD continuously recruited between 1995 and 2010 based on physician referral. Data on history of smoking behaviour was obtained for all participants through a written questionnaire. Using a case-only design, we performed logistic regression analyses to investigate statistical interactions between NOD2 risk alleles and smoking status. We detected a significant negative interaction between carriership of at least one of the NOD2 risk alleles and history of ever having smoked (OR = 0.71; p = 0.005) as well as smoking at the time of CD diagnosis (OR = 0.68; p = 0.005). Subsequent separate analyses of the three variants revealed a significant negative interaction between the 1007fs variant and history of ever having smoked (OR = 0.64; p = 9 × 10-4) and smoking at the time of CD diagnosis (OR = 0.53; p = 7 × 10-5). The observed significant negative gene-environment interaction suggests that the risk increase for CD conferred simultaneously by cigarette smoking and the 1007fs NOD2 polymorphism is smaller than expected and may point to a biological interaction. Our findings warrant further investigation in epidemiological and functional studies to elucidate pathophysiology as well as to aid in the development of recommendations for disease prevention.
    BMC Medical Genetics 03/2012; 13:14. · 2.54 Impact Factor
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    ABSTRACT: The clinical course of Crohn's disease (CD) is highly variable with a subgroup of patients developing a progressive disease course necessitating immunosuppressive therapy (IT). However, reliable, stable and non-invasive individual clinical parameters in order to identify patients at risk for undergoing subsequent IT have not been sufficiently established. We therefore aimed to identify such clinical parameters. A retrospective, multicenter analysis of CD patients from 6 German tertiary IBD centers was performed. Patients were classified into two groups depending on requiring IT or not. Personal data, clinical and laboratory parameters during the first 3 months after CD diagnosis and effects of initial medical therapy were compared between these two groups. In 218 (61.8%) of the 353 patients the CD course necessitated IT. Those patients were significantly younger at symptom onset and diagnosis, and required significantly more often a systemic corticosteroid therapy. Furthermore, significant differences in serological markers of inflammation were observed. Age, gender and the effect of initial steroid therapy were used to develop a prognostic model predicting the individual probability of necessitating IT. The simple clinical items age at diagnosis, gender, and need for systemic steroid therapy can predict a progressive disease course in early CD. Our model based on these parameters allows an individualized estimation of each patient's risk to develop a progressive disease course. Thereby, our model can help in deciding if patients will need immunosuppressive drugs early in the disease course or if a careful watch and wait strategy is justified.
    Journal of Crohn s and Colitis 02/2012; 6(1):21-8. · 3.39 Impact Factor
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    ABSTRACT: Micro-RNAs (miRNAs) are short, non-coding RNAs that regulate gene expression post transcriptionally. Several studies have demonstrated the relevance of miRNAs for a wide range of cellular mechanisms, however, the current knowledge on how miRNAs respond to relevant external stimuli, e.g. in disease scenarios is very limited. To generate a descriptive picture of the miRNA network associated to inflammatory responses, we quantified the levels of 330 miRNAs upon stimulation with a panel of pro-inflammatory components such as microbial pattern molecules (flagellin, diacylated lipopeptide lipopolysaccharide, muramyl dipeptide), infection with Listeria monocytogenes and TNF-α as pro-inflammatory control in primary human monocytes using real time PCR. As a result, we found distinct miRNA response clusters for each stimulus used. Additionally, we identified potential target genes of three selected miRNAs miR-129-5p, miR-146a and miR-378 which were part of PAMP-specific response clusters by transfecting THP1 monocytes with the corresponding pre- or anti-miRNAs and microfluidic PCR arrays. The miRNAs induced distinct transcriptomal signatures, e.g. overexpression of miRNA129-5p, which was selectively upregulated by the NOD2-elicitor MDP, led to an upregulation of DEFB1, IRAK1, FBXW7 and IKK γ (Nemo). Our findings on highly co-regulated clusters of miRNAs support the hypothesis that miRNAs act in functional groups. This study indicates that miRNAs play an important role in fine-tuning inflammatory mechanisms. Further investigation in the field of miRNA responses will help to understand their effects on gene expression and may close the regulatory gap between mRNA and protein expression in inflammatory diseases.
    PLoS ONE 01/2012; 7(2):e31151. · 3.53 Impact Factor
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    ABSTRACT: Intestinal barrier function in Crohn's disease patients and their first degree healthy relatives is impaired. The increased intestinal permeability may result in an enhanced mucosal immune response and thereby aggravate intestinal inflammation. Humanised anti-TNF-α antibodies have been shown to be effective in the treatment of active Crohn's disease and in the treatment of entero-cutaneous fistula. The aim of the present study was to investigate the influence of anti-TNF-α antibody (infliximab) treatment on the intestinal barrier function of patients with active Crohn's disease. The differential intestinal uptake of lactulose and mannitol was measured to quantify intestinal permeability in patients with long standing active Crohn's disease (n=17) directly before and seven days after treatment with infliximab (5 mg/kg bodyweight). In parallel, intestinal permeability was studied in a healthy control group (n=20). Serum samples were analysed with pulsed amperometric detection after separation on an anion exchange column. Intestinal permeability was significantly increased in all patients with Crohn's disease (L/M ratio 0.24±0.17) prior to infliximab treatment compared to the control group (L/M ratio 0.01±0.02; p-value <1×10(-7)). Treatment of patients with infliximab resulted in a marked decrease of intestinal permeability as measured by L/M ratio from 0.24±0.17 before to 0.02±0.02 (p-value <1×10(-7)) seven days after infliximab application. Treatment with anti-TNF-α antibodies improved impaired intestinal barrier function in patients with Crohn's disease. This effect may correlate to the well documented anti-inflammatory effect of TNF-α blockade in this intestinal disease.
    Journal of Crohn s and Colitis 11/2011; 6(4):464-9. · 3.39 Impact Factor
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    ABSTRACT: Cytochrome P450 enzymes, especially the CYP2C subfamily, are involved in the generation of reactive oxygen species and are regarded as susceptibility factors for age-related diseases. Furthermore, the CYP2C-encoding genes are known to be highly polymorphic, with a number of variants leading to changes in enzyme activity. These observations prompted us to investigate whether allelic variation in the CYP2C-encoding genes was associated with human longevity. In a comprehensive haplotype tagging approach, we genotyped 56 single nucleotide polymorphisms located in the CYP2C gene family (CYP2C8, CYP2C9, CYP2C18, and CYP2C19) in our extensive collection of 1,384 long-lived individuals (centenarians and nonagenarians) and 945 younger controls. None of the tested single nucleotide polymorphisms showed a significant association with the longevity phenotype at the allele, genotype, or haplotype level. These results suggest that there is no notable influence of sequence variation in the CYP2C genes on longevity in the examined German population.
    The Journals of Gerontology Series A Biological Sciences and Medical Sciences 07/2011; 66(11):1186-91. · 4.31 Impact Factor
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    ABSTRACT: We conducted a case-control genome-wide association study (GWAS) of human longevity, comparing 664,472 autosomal SNPs in 763 long-lived individuals (LLI; mean age: 99.7 years) and 1085 controls (mean age: 60.2 years) from Germany. Only one association, namely that of SNP rs4420638 near the APOC1 gene, achieved genome-wide significance (allele-based P=1.8×10(-10)). However, logistic regression analysis revealed that this association, which was replicated in an independent German sample, is fully explicable by linkage disequilibrium with the APOE allele ɛ4, the only variant hitherto established as a major genetic determinant of survival into old age. Our GWAS failed to identify any additional autosomal susceptibility genes. One explanation for this lack of success in our study would be that GWAS provide only limited statistical power for a polygenic phenotype with loci of small effect such as human longevity. A recent GWAS in Dutch LLI independently confirmed the APOE-longevity association, thus strengthening the conclusion that this locus is a very, if not the most, important genetic factor influencing longevity.
    Mechanisms of ageing and development 06/2011; 132(6-7):324-30. · 4.18 Impact Factor
  • Gastrointestinal Endoscopy 04/2011; 73(4). · 5.21 Impact Factor
  • Tanja Kuehbacher, Susanna Nikolaus, Stefan Schreiber
    Gastroenterology 01/2011; 140(5). · 12.82 Impact Factor
  • Gastroenterology 01/2011; 140(5). · 12.82 Impact Factor
  • Gastroenterology 01/2011; 140(5). · 12.82 Impact Factor
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    ABSTRACT: We sought to analyze the efficacy (response and remission) and safety data from the PRECiSE 2 trial of certolizumab pegol according to duration of Crohn's disease since diagnosis at baseline. Responders to induction treatment with certolizumab pegol at week 6 in PRECiSE 2 (n=425) were randomized to receive certolizumab pegol 400 mg (n=215) or placebo (n=210) until week 26. Logistic regression analysis identified factors linked to Crohn's disease history (short duration, no prior infliximab use, no corticosteroids, no operations) as prognostics of outcome. Efficacy (response, remission) and safety data were reanalyzed according to duration of Crohn's disease since diagnosis at baseline. The proportions of patients in response at study end were inversely related to duration of Crohn's disease. Maintenance of response with certolizumab pegol was achieved in 89.5% of patients with a diagnosis <1 year (P<0.01 vs. placebo), compared with 57.3% of patients with a diagnosis > or = 5 years (P<0.001 vs. placebo). Corresponding remission rates were 68.4% (P<0.05 vs. placebo) and 44.3% (P<0.001 vs. placebo), respectively. Response and remission rates did not differ significantly by disease duration in placebo subgroups. Incidences of adverse events were unaffected by duration of disease at baseline. These data suggest that patients treated with certolizumab pegol 400 mg earlier rather than later, with a confirmed Crohn's disease diagnosis, may achieve better treatment outcomes.
    The American Journal of Gastroenterology 03/2010; 105(7):1574-82. · 9.21 Impact Factor

Publication Stats

5k Citations
956.97 Total Impact Points

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Institutions

  • 2004–2014
    • University Medical Center Schleswig-Holstein
      Kiel, Schleswig-Holstein, Germany
  • 2000–2013
    • Christian-Albrechts-Universität zu Kiel
      • • Institute of Clinical Molecular Biology
      • • Institute of Human Nutrition and Food Science
      Kiel, Schleswig-Holstein, Germany
    • Dalhousie University
      Halifax, Nova Scotia, Canada
  • 2004–2008
    • Universitätsklinikum Schleswig - Holstein
      • Institut für Klinische Molekularbiologie (Kiel)
      Kiel, Schleswig-Holstein, Germany
  • 2006
    • Institute of Molecular Biology
      Mayence, Rheinland-Pfalz, Germany
  • 1996–1998
    • Humboldt-Universität zu Berlin
      Berlín, Berlin, Germany
    • Humboldt State University
      Arcata, California, United States
  • 1995
    • University of Hamburg
      Hamburg, Hamburg, Germany