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Dive into the research topics where Ad A. van Bodegraven is active.

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Featured researches published by Ad A. van Bodegraven.


Journal of Experimental Medicine | 2004

Helicobacter pylori modulates the T helper cell 1/T helper cell 2 balance through phase-variable interaction between lipopolysaccharide and DC-SIGN

Mathijs P. Bergman; Anneke Engering; Hermelijn H. Smits; Sandra J. van Vliet; Ad A. van Bodegraven; Hans-Peter Wirth; Martien L. Kapsenberg; Christina M. J. E. Vandenbroucke-Grauls; Yvette van Kooyk; Ben J. Appelmelk

The human gastric pathogen Helicobacter pylori spontaneously switches lipopolysaccharide (LPS) Lewis (Le) antigens on and off (phase-variable expression), but the biological significance of this is unclear. Here, we report that Le+ H. pylori variants are able to bind to the C-type lectin DC-SIGN and present on gastric dendritic cells (DCs), and demonstrate that this interaction blocks T helper cell (Th)1 development. In contrast, Le− variants escape binding to DCs and induce a strong Th1 cell response. In addition, in gastric biopsies challenged ex vivo with Le+ variants that bind DC-SIGN, interleukin 6 production is decreased, indicative of increased immune suppression. Our data indicate a role for LPS phase variation and Le antigen expression by H. pylori in suppressing immune responses through DC-SIGN.


Gut | 2014

Adalimumab combined with ciprofloxacin is superior to adalimumab monotherapy in perianal fistula closure in Crohn's disease: a randomised, double-blind, placebo controlled trial (ADAFI)

Pieter Dewint; Bettina E. Hansen; Elke Verhey; Bas Oldenburg; Daniel W. Hommes; Marieke Pierik; Cyriel I. J. Ponsioen; Hendrik M. van Dullemen; Maurice G. Russel; Ad A. van Bodegraven; C. Janneke van der Woude

Objective To assess whether a combination of adalimumab and ciprofloxacin is superior to adalimumab alone in the treatment of perianal fistulising Crohns disease (CD). Design Randomised, double-blind, placebo controlled trial in eight Dutch hospitals. In total, 76 CD patients with active perianal fistulising disease were enrolled. After adalimumab induction therapy (160/80u2005mg week 0, 2), patients received 40u2005mg every other week together with ciprofloxacin 500u2005mg or placebo twice daily for 12u2005weeks. After 12u2005weeks, adalimumab was continued. Follow-up was 24u2005weeks. Primary endpoint (clinical response) was defined as 50% reduction of fistulas from baseline to week 12. Secondary endpoints included remission (closure of all fistulas), Perianal Crohns Disease Activity Index, Crohns Disease Activity Index (CDAI) and Inflammatory Bowel Disease Questionnaire (IBDQ). Results Clinical response was observed in 71% of patients treated with adalimumab plus ciprofloxacin and in 47% treated with adalimumab plus placebo (p=0.047). Likewise, remission rate at week 12 was significantly higher (p=0.009) in the combination group (65%) compared with adalimumab plus placebo (33%). Combination treatment was associated with a higher mean CDAI change and mean IBDQ change at week 12 (p=0.005 and p=0.009, respectively). At week 24, no difference in clinical response between the two treatment groups was observed (p=0.22). No difference in safety issues was observed. Conclusions Combination therapy of adalimumab and ciprofloxacin is more effective than adalimumab monotherapy to achieve fistula closure in CD. However, after discontinuation of antibiotic therapy, the beneficial effect of initial coadministration is not maintained. Trial registration ClinicalTrials.gov Identifier: NCT00736983.


The Journal of Sexual Medicine | 2014

Intestinal Vaginoplasty Revisited: A Review of Surgical Techniques, Complications, and Sexual Function

Mark-Bram Bouman; Michiel C.T. van Zeijl; Marlon E. Buncamper; W. J. H. J. Meijerink; Ad A. van Bodegraven; Margriet G. Mullender

INTRODUCTIONnVaginal (re)construction is essential for the psychological well-being of biological women with a dysfunctional vagina and male-to-female transgender women. However, the preferred method for vagina (re)construction with respect to functional as well as aesthetic outcomes is debated. Regarding intestinal vaginoplasty, despite the asserted advantages, the need for intestinal surgery and subsequent risk of diversion colitis are often-mentioned concerns. The outcomes of vaginal reconstructive surgery need to be appraised in order to improve understanding of pros and cons.nnnAIMSnTo review literature on surgical techniques and clinical outcomes of intestinal vaginoplasty.nnnMETHODSnElectronic databases and reference lists of published articles were searched for primary studies on intestinal vaginoplasty. Studies were included if these included at least five patients and had a minimal follow-up period of 1 year. No constraints were imposed with regard to patient age, indication for vaginoplasty, or applied surgical technique. Outcome measures were extracted and analyzed.nnnMAIN OUTCOME MEASURESnMain outcome measures were surgical procedure, clinical outcomes, and outcomes concerning sexual health and quality of life.nnnRESULTSnTwenty-one studies on intestinal vaginoplasty were included (including 894 patients in total). All studies had a retrospective design and were of low quality. Prevalence and severity of procedure-related complications were low. The main postoperative complication was introital stenosis, necessitating surgical correction in 4.1% of sigmoid-derived and 1.2% of ileum-derived vaginoplasties. Neither diversion colitis nor cancer was reported. Sexual satisfaction rate was high, but standardized questionnaires were rarely used. Quality of life was not reported.nnnCONCLUSIONnBased on evidence presently available, it seems that intestinal vaginoplasty is associated with low complication rates. To substantiate these findings and to obtain information about functional outcomes and quality of life, prospective studies using standardized measures and questionnaires are warranted.


Clinical Gastroenterology and Hepatology | 2013

Adalimumab and Infliximab Are Equally Effective for Crohn's Disease in Patients Not Previously Treated With Anti–Tumor Necrosis Factor-α Agents

Christine Kestens; Martijn G. van Oijen; Charlotte L.J. Mulder; Ad A. van Bodegraven; Gerard Dijkstra; Dirk J. de Jong; Cyriel Y. Ponsioen; Bas A.C. van Tuyl; Peter D. Siersema; Herma H. Fidder; Bas Oldenburg

BACKGROUND & AIMSnInfliximab (IFX) and adalimumab (ADA) are thought to have equal efficacy for the treatment of Crohns disease (CD), although no direct comparison has been performed. We compared the effectiveness and safety of IFX and ADA in carefully matched cohorts.nnnMETHODSnWe performed a retrospective cohort study of 200 patients with CD (100 treated with IFX and 100 treated with ADA, starting in 2006 or later) who had not received anti-tumor necrosis factor α agents previously; the patients were identified from databases of 6 hospitals in The Netherlands. The groups were matched carefully for indication, duration of disease, age, and Montreal classification. The primary end point was the steroid-free clinical response, defined by a combination of multiple clinical parameters, after 1 year.nnnRESULTSnOf the total patient population, 63.5% and 45% had a clinical response after 1 and 2 years, respectively. There were no significant differences between treatment groups: at 1 and 2 years, 62% and 41% of those receiving ADA vs 65% and 49% of those receiving IFX had responses, respectively. Kaplan-Meier curves showed identical decreases in response rates over time. Combining IFX or ADA with immunomodulator therapy was associated with a higher clinical response than monotherapy, although this was only significant among patients who received IFX (P = .03). There were no differences in numbers of side effects or opportunistic infections.nnnCONCLUSIONSnThe effectiveness of ADA or IFX treatment in anti-tumor necrosis factor α-naive patients with CD is comparable after 1 and 2 years of follow-up evaluation. The efficacies of IFX and ADA each seem to increase when given with immunomodulator therapy, although only significantly for IFX.


Inflammatory Bowel Diseases | 2009

Local Application of Tacrolimus in Distal Colitis: Feasible and Safe

Jolanda M. van Dieren; Ad A. van Bodegraven; Ernst J. Kuipers; Eke N. Bakker; Alexander C. Poen; Herman van Dekken; Edward E. S. Nieuwenhuis; C. Janneke van der Woude

Background: Tacrolimus is a potent immunomodulator that is effective in the systemic treatment of inflammatory bowel diseases (IBD). However, potential toxicity and systemic (side) effects after oral intake limit its use. We investigated the local applicability and safety of tacrolimus for distal colitis. Methods: Patients with refractory left‐sided colitis or proctitis were treated for 4 weeks with a daily tacrolimus 2–4 mg enema or 2 mg suppository. Safety of local tacrolimus treatment was assessed by measurement of whole blood tacrolimus trough levels by monitoring liver and kidney function and blood glucose levels. Efficacy of treatment was assessed by comparing the disease activity index (DAI) in ulcerative colitis (UC) patients and endoscopic and histologic appearances before and after 4 weeks of treatment. Results: Nineteen patients with left‐sided colitis (n = 7) or proctitis (n = 12) were treated. Two patients with left‐sided colitis had Crohns disease (CD), the other 17 patients had UC. None of the patients developed side effects. Blood trough levels of tacrolimus were too low to induce systemic immune suppression. Thirteen of 19 patients (3/5 left‐sided UC, 0/2 left‐sided CD, and 10/12 proctitis) showed clinical improvement of disease activity after 4 weeks of local tacrolimus treatment. Moreover, a significant improvement of histological appearance was observed in the suppository‐treated group. Conclusions: This study demonstrates that local colonic application of tacrolimus 2–4 mg daily in patients with refractory distal colitis is feasible, probably safe, and potentially efficacious, and therefore opens the need for a further, randomized trial.


Gastroenterology | 2011

Histomorphometric Analysis Reveals Reduced Bone Mass and Bone Formation in Patients With Quiescent Crohn's Disease

Angela E. Oostlander; Nathalie Bravenboer; E. Sohl; Paulien J. Holzmann; Christien J. van der Woude; Gerard Dijkstra; Pieter Stokkers; Bas Oldenburg; J. Coen Netelenbos; Daniel W. Hommes; Ad A. van Bodegraven; Paul Lips

BACKGROUND & AIMSnCrohns disease (CD) is associated with an increased prevalence of osteoporosis, but the pathogenesis of this bone loss is only partly understood. We assessed bone structure and remodeling at the tissue level in patients with quiescent CD. We also investigated the roles of osteocyte density and apoptosis in CD-associated bone loss.nnnMETHODSnThe study included 23 patients with quiescent CD; this was a subgroup of patients from a large randomized, double-blind, placebo-controlled, multicenter trial. We obtained transiliac bone biopsy samples and performed histomorphometric analysis. Results were compared with data from age- and sex-matched healthy individuals (controls).nnnRESULTSnTrabecular bone volume was decreased among patients with CD compared with controls (18.90% vs 25.49%; P < .001). The low bone volume was characterized by decreased trabecular thickness (120.61 vs 151.42 μm; P < .01). Bone formation and resorption were reduced, as indicated by a decreased mineral apposition rate (0.671 vs 0.746 μm/day; P < .01) and a low osteoclast number and surface area compared with controls and published values, respectively. In trabecular bone of patients with CD, osteocyte density and apoptosis were normal. The percentage of empty lacunae among patients was higher than that of published values in controls.nnnCONCLUSIONSnIn adult patients with quiescent CD, bone histomorphometric analysis revealed a reduction in bone mass that was characterized by trabecular thinning. The CD-associated bone loss was caused by reduced bone formation, possibly as a consequence of decreased osteocyte viability in the patients past.


Inflammatory Bowel Diseases | 2011

Misclassification of Dysplasia in Patients with Inflammatory Bowel Disease: Consequences for Progression Rates to Advanced Neoplasia

Fiona van Schaik; Fiebo J. ten Kate; G. Johan A. Offerhaus; Marguerite E.I. Schipper; Frank P. Vleggaar; C. Janneke van der Woude; Pieter Stokkers; Dirk J. de Jong; Daan W. Hommes; Ad A. van Bodegraven; Peter D. Siersema; Bas Oldenburg

Background: The natural behavior of flat low‐grade (LGD) and indefinite dysplasia (IND) in patients with inflammatory bowel disease (IBD) remains uncertain and seems to be dependent on the interpretation of the pathologist. We studied the progression rate of flat LGD and IND to advanced neoplasia (high‐grade dysplasia [HGD] or colorectal cancer [CRC]) before and after histopathological review by a panel of gastrointestinal expert pathologists. Methods: A nationwide pathology database was used to identify IBD patients with dysplasia in six Dutch university medical centers between 1990 and 2006. Medical charts of patients with recorded flat LGD or IND were reviewed. Histological slides from three university medical centers were reviewed by a panel of three expert gastrointestinal pathologists. Results: We identified 113 flat LGD patients and 26 flat IND patients. Advanced neoplasia was found in 18 flat LGD patients (16%) after a median follow‐up of 48 months, resulting in a 5‐year progression rate of 12%. Five IND patients (19%) developed advanced neoplasia after a median follow‐up of 24 months, resulting in a 5‐year progression rate of 21%. Review of 1547 histological slides from 87 patients resulted in an increase of the 5‐year progression rate of flat LGD to advanced neoplasia to 37%, whereas the progression rate of IND decreased to 5%. Conclusions: A diagnosis of flat LGD that is confirmed by a panel of expert gastrointestinal pathologists is associated with a substantial risk of progression to advanced neoplasia, while confirmed IND is associated with a low risk of progression. (Inflamm Bowel Dis 2010;)


Critical Care | 2011

Malabsorption and nutritional balance in the ICU: fecal weight as a biomarker: a prospective observational pilot study

J. Nicolette Wierdsma; H.C. Job Peters; J.M. Peter Weijs; B. Martjin Keur; R.J. Armand Girbes; Ad A. van Bodegraven; Albertus Beishuizen

IntroductionMalabsorption, which is frequently underdiagnosed in critically ill patients, is clinically relevant with regard to nutritional balance and nutritional management. We aimed to validate the diagnostic accuracy of fecal weight as a biomarker for fecal loss and additionally to assess fecal macronutrient contents and intestinal absorption capacity in ICU patients.MethodsThis was an observational pilot study in a tertiary mixed medical-surgical ICU in hemodynamically stable adult ICU patients, without clinically evident gastrointestinal malfunction. Fecal weight (grams/day), fecal energy (by bomb calorimetry in kcal/day), and macronutrient content (fat, protein, and carbohydrate in grams/day) were measured. Diagnostic accuracy expressed in terms of test sensitivity, specificity, positive (PPV) and negative predictive value (NPV), and receiver operator curves (ROCs) were calculated for fecal weight as a marker for energy malabsorption. Malabsorption was a priori defined as < 85% intestinal absorption capacity.ResultsForty-eight patients (63 ± 15 years; 58% men) receiving full enteral feeding were included. A cut-off fecal production of > 350 g/day (that is, diarrhea) was linked to the optimal ROC (0.879), showing a sensitivity and PPV of 80%, respectively. Specificity and NPV were both 96%. Fecal weight (grams/day) and intestinal energy-absorption capacity were inversely correlated (r = -0.69; P < 0.001). Patients with > 350 g feces/day had a significantly more-negative energy balance compared with patients with < 350 g feces/day (loss of 627 kcal/day versus neutral balance; P = 0.012).ConclusionsA fecal weight > 350 g/day in ICU patients is a biomarker applicable in daily practice, which can act as a surrogate for fecal energy loss and intestinal energy absorption. Daily measurement of fecal weight is a feasible means of monitoring the nutritional status of critically ill patients and, in those identified as having malabsorption, can monitor responses to changes in dietary management.


Journal of Crohns & Colitis | 2012

Hepatotoxicity associated with 6-methyl mercaptopurine formation during azathioprine and 6-mercaptopurine therapy does not occur on the short-term during 6-thioguanine therapy in IBD treatment

Dirk P. van Asseldonk; Margien L. Seinen; Nanne K.H. de Boer; Ad A. van Bodegraven; Chris J. Mulder

BACKGROUND AND AIMSnHigh concentrations of methylated thiopurine metabolites, such as 6-methyl mercaptopurine, are associated with hepatotoxicity during administration of the conventional thiopurines azathioprine or 6-mercaptopurine in IBD patients. Metabolization of the non-conventional thiopurine 6-thioguanine does not generate 6-methyl mercaptopurine. Hence, the aim of our study was to evaluate hepatotoxicity during 6-thioguanine in IBD patients who previously failed conventional thiopurines due to 6-methyl mercaptopurine associated hepatotoxicity.nnnMETHODSnA retrospective single center intercept cohort study was performed of IBD patients using 6-thioguanine between January 2006 and July 2010 after failing conventional thiopurine therapy due to 6-methyl mercaptopurine associated hepatotoxicity. The primary outcome was the occurrence of 6-thioguanine induced hepatotoxicity, scaled according to the Common Terminology Criteria for Adverse Events.nnnRESULTSnNineteen patients were included. Median duration of 6-thioguanine therapy (median daily dosage 21 mg (9-24)) was 23 weeks (6-96). Hepatotoxicity did not reoccur in 15 out of 19, whereas grade 1 toxicity persisted in 4 patients (p<0.001). Median aspartate aminotransferase and alanine aminotransferase concentrations decreased from 34 U/l (20-59) and 64 U/l (15-175) to 23 U/l (18-40; p=0.003) and 20 U/l (14-48; p=0.019), respectively.nnnCONCLUSIONnHepatotoxicity does not reoccur during 6-thioguanine treatment in most IBD patients who failed conventional thiopurines due to 6-methyl mercaptopurine associated hepatotoxicity. Hence, at least at short-term, 6-thioguanine appears a justifiable alternative thiopurine for these IBD patients.


Journal of Cellular Biochemistry | 2012

T cell-mediated increased osteoclast formation from peripheral blood as a mechanism for crohn's disease-associated bone loss

Angela E. Oostlander; Vincent Everts; Ton Schoenmaker; Nathalie Bravenboer; Sandra J. van Vliet; Ad A. van Bodegraven; Paul Lips; Teun J. de Vries

The pathophysiology of osteoporosis in patients with Crohns disease (CD) is still not completely elucidated. In this study, we evaluated osteoclastogenesis from peripheral blood cells of CD patients and studied the role of lymphocytes and inflammatory cytokines in this process. Peripheral blood mononuclear cells from seven patients with quiescent CD and matched healthy controls were isolated, and separated into T cells, B cells, and a T‐ and B‐cell depleted fraction. In various culture combinations, osteoclast formation in the absence of the osteoclastogenic factors RANKL and M‐CSF was assessed by scoring the number of tartrate‐resistant acid phosphatase (TRACP) positive multinucleated cells (MNCs). Cytokine levels in culture supernatants were measured. Formation of heterogeneous cell clusters in culture was noticed; a process that was inhibited by anti‐LFA‐1. In CD cultures, mean cluster area was up to threefold higher than in control cultures, and shown to be induced by T cells. Over tenfold higher numbers of TRACP+ MNCs were found in CD cultures, but exclusively in cultures containing T cells. Formation of cell clusters correlated strongly with formation of TRACP+ MNCs. Both cell cluster formation and osteoclast formation were related to IL‐17 levels in vitro. In conclusion, osteoclastogenesis, preceded by cell cluster formation, is T cell‐mediated and increased in patients with quiescent CD. Our findings suggest heterotypic interactions between osteoclast precursors and T cells to be a triggering step in osteoclast formation in CD. Furthermore, our results propose a possible role for IL‐17 in osteoclastogenesis in CD patients, and as such in CD‐associated bone loss. J. Cell. Biochem. 113: 260–268, 2012.

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Gerard Dijkstra

University Medical Center Groningen

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Angela E. Oostlander

VU University Medical Center

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Dirk J. de Jong

Radboud University Nijmegen

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Nathalie Bravenboer

VU University Medical Center

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Paul Lips

VU University Medical Center

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