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Your search keyword '"Ronald K Linskens"' showing total 8 results
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8 results on '"Ronald K Linskens"'

1. Genetic association analysis of the functional c.714T>G polymorphism and mucosal expression of dectin-1 in inflammatory bowel disease.

Author

Hilbert S de Vries, Theo S Plantinga, J Han van Krieken, Rinke Stienstra, Ad A van Bodegraven, Eleonora A M Festen, Rinse K Weersma, J Bart A Crusius, Ronald K Linskens, Leo A B Joosten, Mihai G Netea, and Dirk J de Jong

Subjects
Medicine, Science
Abstract

BACKGROUND: Dectin-1 is a pattern recognition receptor (PRR) expressed by myeloid cells that specifically recognizes beta-1,3 glucan, a polysaccharide and major component of the fungal cell wall. Upon activation, dectin-1 signaling converges, similar to NOD2, on the adaptor molecule CARD9 which is associated with inflammatory bowel disease (IBD). An early stop codon polymorphism (c.714T>G) in DECTIN-1 results in a loss-of-function (p.Y238X) and impaired cytokine responses, including TNF-alpha, interleukin (IL)-1beta and IL-17 upon in vitro stimulation with Candida albicans or beta-glucan. The aim of the present study was to test the hypothesis that the DECTIN-1 c.714T>G (p.Y238X) polymorphism is associated with lower disease susceptibility or severity in IBD and to investigate the level of dectin-1 expression in inflamed and non-inflamed colon tissue of IBD patients. METHODOLOGY: Paraffin embedded tissue samples from non-inflamed and inflamed colon of IBD patients and from diverticulitis patients were immunohistochemically stained for dectin-1 and related to CD68 macrophage staining. Genomic DNA of IBD patients (778 patients with Crohn's disease and 759 patients with ulcerative colitis) and healthy controls (n = 772) was genotyped for the c.714T>G polymorphism and genotype-phenotype interactions were investigated. PRINCIPAL FINDINGS: Increased expression of dectin-1 was observed in actively inflamed colon tissue, as compared to non-inflamed tissue of the same patients. Also an increase in dectin-1 expression was apparent in diverticulitis tissue. No statistically significant difference in DECTIN-1 c.714T>G allele frequencies was observed between IBD patients and healthy controls. Furthermore, no differences in clinical characteristics could be observed related to DECTIN-1 genotype, neither alone, nor stratified for NOD2 genotype. CONCLUSIONS: Our data demonstrate that dectin-1 expression is elevated on macrophages, neutrophils, and other immune cells involved in the inflammatory reaction in IBD. The DECTIN-1 c.714T>G polymorphism however, is not a major susceptibility factor for developing IBD.

Published
2009
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2. Quantification of bacteria adherent to gastrointestinal mucosa by real-time PCR

Author

Christina M. J. E. Vandenbroucke-Grauls, Ronald K. Linskens, Xander W. Huijsdens, Stephan G. M. Meuwissen, Mariette Mak, Paul H. M. Savelkoul, and Medical Microbiology and Infection Prevention

Subjects
Microbiology (medical), Colon, Colony Count, Microbial, medicine.disease_cause, DNA, Ribosomal, Polymerase Chain Reaction, Sensitivity and Specificity, Bacterial Adhesion, law.invention, Microbiology, chemistry.chemical_compound, Intestinal mucosa, law, RNA, Ribosomal, 16S, medicine, Escherichia coli, Bacteroides, Humans, Taq Polymerase, Intestinal Mucosa, Polymerase chain reaction, Nuclease, biology, Bacteriology, biology.organism_classification, Molecular biology, Real-time polymerase chain reaction, chemistry, biology.protein, Bacteria, Taq polymerase
Abstract

The use of real-time quantitative PCR (5′ nuclease PCR assay) as a tool to study the gastrointestinal microflora that adheres to the colonic mucosa was evaluated. We developed primers and probes based on the 16S ribosomal DNA gene sequences for the detection of Escherichia coli and Bacteroides vulgatus . DNA was isolated from pure cultures and from gut biopsy specimens and quantified by the 5′ nuclease PCR assay. The assay showed a very high sensitivity: as little as 1 CFU of E. coli and 9 CFU of B. vulgatus could be detected. The specificities of the primer-probe combinations were evaluated with samples that were spiked with the species most closely related to E. coli and B. vulgatus and with eight other gut microflora species. Mucosal samples spiked with known amounts of E. coli or B. vulgatus DNA showed no PCR inhibition. We conclude that the 5′ nuclease PCR assay may be a useful alternative to conventional culture techniques to study the actual in vivo composition of a complex microbial community like the gut microflora.

Published
2002
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3. Endocrinology through an endoscope: lesions in the esophagus, stomach, and duodenum in gastrinoma

Author

Ernst J. Kuipers, Peter Mensink, Ronald K. Linskens, Huseyin Aktas, Ewout J. Hoorn, Internal Medicine, and Gastroenterology & Hepatology

Subjects
Esophagus stomach, Male, Gastrinoma, medicine.medical_specialty, Endoscope, business.industry, General surgery, Gastroenterology, Endoscopy, Anatomy, Middle Aged, medicine.disease, Pancreatic Neoplasms, medicine.anatomical_structure, medicine, Duodenum, Humans, business, Gastrointestinal Hemorrhage
Published
2011

4. Detection of Helicobacter species DNA by quantitative PCR in the gastrointestinal tract of healthy individuals and of patients with inflammatory bowel disease

Author

José Koppes, Yuan Lan Tang, Ronald K. Linskens, Stephan G. M. Meuwissen, Xander W. Huijsdens, Paul H. M. Savelkoul, Christina M. J. E. Vandenbroucke-Grauls, and Medical Microbiology and Infection Prevention

Subjects
Microbiology (medical), DNA, Bacterial, medicine.medical_specialty, Spirillaceae, Biopsy, Immunology, Microbiology, Gastroenterology, Inflammatory bowel disease, Polymerase Chain Reaction, Internal medicine, Helicobacter, medicine, Immunology and Allergy, Humans, Intestinal Mucosa, DNA Primers, Gastrointestinal tract, biology, medicine.diagnostic_test, Helicobacter pylori, Human gastrointestinal tract, Mucous membrane, General Medicine, biology.organism_classification, medicine.disease, Inflammatory Bowel Diseases, Infectious Diseases, medicine.anatomical_structure, Gastric Mucosa
Abstract

In many animal species different intestinal Helicobacter species have been described and a few species are associated with intestinal infection. In humans, the only member of the Helicobacter family which is well described in literature is Helicobacter pylori. No other Helicobacter-associated diseases have definitely been shown in humans. We developed a sensitive quantitative PCR to investigate whether Helicobacter species DNA can be detected in the human gastrointestinal tract. We tested gastric biopsies (including biopsies from H. pylori positive persons), intestinal mucosal biopsies and fecal samples from healthy persons, and intestinal mucosal biopsies from patients with inflammatory bowel disease (IBD) for the presence of Helicobacter species. All gastric biopsies, positive for H. pylori by culture, were also positive in our newly developed PCR. No Helicobacter species were found in the mucosal biopsies from patients with IBD (n = 50) nor from healthy controls (n = 25). All fecal samples were negative. Our study suggests that Helicobacter species, other than H. pylori, are not present in the normal human gastrointestinal flora and our results do not support a role of Helicobacter species in IBD.

Published
2004

5. Listeria monocytogenes and inflammatory bowel disease: detection of Listeria species in intestinal mucosal biopsies by real-time PCR

Author

Ronald K. Linskens, Christina M. J. E. Vandenbroucke-Grauls, P. H. M. Savelkoul, Stephan G. M. Meuwissen, Xander W. Huijsdens, H. Taspinar, and Medical Microbiology and Infection Prevention

Subjects
medicine.diagnostic_test, Crohn disease, business.industry, Gastroenterology, medicine.disease, medicine.disease_cause, Inflammatory bowel disease, Ulcerative colitis, Listeria species, Pathogenesis, Real-time polymerase chain reaction, Listeria monocytogenes, Immunology, Biopsy, medicine, business, human activities
Abstract

(2003). Listeria monocytogenes and Inflammatory Bowel Disease. Scandinavian Journal of Gastroenterology: Vol. 38, No. 3, pp. 332-333.

Published
2003

6. S1231 Predictors for Failing Thiopurine Therapy in IBD Patients; Treated At An Academic or General District Hospital

Author

Chris J. J. Mulder, Ronald K. Linskens, Margien L. Seinen, Bindia Jharap, Nanne K. H. de Boer, Ad A. van Bodegraven, and Jan Kees Kneppelhout

Subjects
medicine.medical_specialty, Hepatology, Thiopurine methyltransferase, biology, business.industry, District hospital, Internal medicine, Gastroenterology, Physical therapy, medicine, biology.protein, business
Published
2008
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8. Real time quantitative PCR of Bacteroides vulgatus and Escherichia coli in mucosal samples from healthy humans and patients with IBD

Author

Paul H. M. Savelkoul, Xander W. Huijsdens, Ronald K. Linskens, Jeroen Stoof, Mariette Mak, Stephan G. M. Meuwissen, and Christina M. J. E. Vandenbroucke-Grauls

Subjects
Real-time polymerase chain reaction, Hepatology, Gastroenterology, Bacteroides vulgatus, medicine, Biology, medicine.disease_cause, Escherichia coli, Microbiology
Published
2000
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