Peptides as quorum sensing molecules : measurement techniques and obtained levels in vitro and in vivo

The expression of certain bacterial genes is regulated in a cell-density dependent way, a phenomenon called quorum sensing. Both Gram-negative and Gram-positive bacteria use this type of communication, though the signal molecules (auto-inducers) used by them differ between both groups: Gram-negative bacteria use predominantly N-acyl homoserine lacton (AHL) molecules (autoinducer-1, AI-1) while Gram-positive bacteria use mainly peptides (autoinducer peptides, AIP or quorum sensing peptides). These quorum sensing molecules are not only involved in the inter-microbial communication, but can also possibly cross-talk directly or indirectly with their host. This review summarizes the currently applied analytical approaches for quorum sensing identification and quantification with additionally summarizing the experimentally found in vivo concentrations of these molecules in humans

Systematic review: steroid withdrawal in anti-TNF-treated patients with inflammatory bowel disease

International audienceBackground: The increasing awareness of increased risk for opportunistic infections when combining several immunosuppressant drugs led to new treatment goals for inflammatory bowel disease (IBD) including limited use of steroids. Aim: We conducted a systematic review to establish steroid withdrawal in anti-TNF treated IBD-patients. Methods: Medline was searched using the search-terms Ulcerative Colitis (UC) [Mesh], Crohn Disease (CD) [Mesh], IBD [Mesh], crohn, colitis, IBD and steroid sparing, all combined with infliximab and adalimumab. We selected English-language publications that addressed the effect of anti-TNF on steroid withdrawal. Studies had to assess patients with luminal CD or UC. Numbers of patients able to withdraw steroids were calculated. Results: Six studies could be included; five reporting on infliximab and one on adalimumab. Studies were heterogeneously designed. Overall in the adult population up to 38% of the patients were able to withdraw corticosteroids during infliximab therapy. In the pediatric population up to 75% of the patients were able to withdraw corticosteroids during infliximab therapy. Conclusions: Although a consensus on the definition of steroid-sparing is lacking, approximately two third of the IBD-patients are unable to withdraw corticosteroid treatment during anti-TNF therapy

Sex-dimorphic adverse drug reactions to immune suppressive agents in inflammatory bowel disease

AIM: To analyze sex differences in adverse drug reactions (ADR) to the immune suppressive medication in inflammatory bowel disease (IBD) patients. METHODS: All IBD patients attending the IBD outpatient clinic of a referral hospital were identified through the electronic diagnosis registration system. The electronic medical records of IBD patients were reviewed and the files of those patients who have used immune suppressive therapy for IBD, i.e., thiopurines, methotrexate, cyclosporine, tacrolimus and anti-tumor necrosis factor agents (anti-TNF); infliximab (IFX), adalimumab (ADA) and/or certolizumab, were further analyzed. The reported AD RESULTS: In total, 1009 IBD patients were identified in the electronic diagnosis registration system. Out of these 1009 patients, 843 patients were eligible for further analysis. There were 386 males (46%), mean age 42 years (range: 16-87 years) with a mean duration of the disease of 14 years (range: 0-54 years); 578 patients with Crohn's disease, 244 with ulcerative colitis and 21 with unclassified colitis. Seventy percent (586 pts) of patients used any kind of immune suppressive agents at a ce CONCLUSION: Treatment with anti-TNF antibodies is accompanied by sexual dimorphic profile of ADR with female patients being more at risk for allergic reactions and subsequent discontinuation of the treatment. (C) 2012 Baishideng. All rights reserved

Predictors of dose escalation of adalimumab in a prospective cohort of Crohn's disease patients

Background Adalimumab is effective for the induction and maintenance of remission in Crohns disease (CD)-patients. Aim To find predictors for adalimumab dose escalation at initiation of adalimumab. Methods Crohn's disease patients in a single tertiary referral centre who started adalimumab between July 2007 and March 2010 at an induction dose (week 0 160 mg subcutaneously (sc), week 2 80 mg sc) and maintenance dose of 40 mg sc thereafter every other week were followed prospectively. Patients on adalimumab for at least 3 months were included. The number of patients needing dose escalation was assessed. Patients that needed dose escalation were compared with patients that did not need dose escalatio Results Of 199 CD patients treated with adalimumab and followed prospectively, 122 patients (M/F 54/68, median age 35 years, range 18-66 years, median CDAI 164, range 6-468) were treated for 3 months. In total 38% of these patients (46 /122) needed a dose escalation within a median time of 21 weeks after adalimumab introduction (range 4-105). Body mass index (BMI) (P < 0.03) and secondary non-response to infliximab (IFX) (P < 0.06) were identified as predictors for dose escalation. Concomitant use of im Conclusions Over one-third adalimumab-treated patients are dose escalated within a median of 5 months. Higher BMI and secondary non-response to IFX treatment are predictive for a dose escalation during adalimumab treatment

Sex-dimorphic adverse drug reactions to immune suppressive agents in inflammatory bowel disease

AIM: To analyze sex differences in adverse drug reactions (ADR) to the immune suppressive medication in inflammatory bowel disease (IBD) patients. METHODS: All IBD patients attending the IBD outpatient clinic of a referral hospital were identifed through the electronic diagnosis registration system. The electronic medical records of IBD patients were reviewed and the files of those patients who have used immune suppressive therapy for IBD, i.e., thiopurines, methotrexate, cyclosporine, tacrolimus and anti-tumor necrosis factor agents (anti-TNF); infiximab (IFX), adalimumab (ADA) and/or certolizumab, were further analyzed. The reported ADR to immune suppressive drugs were noted. The general definition of ADR used in clinical practice comprised the occurrence of the ADR in the temporal relationship with its disappearance upon discontinuation of the medication. Patients for whom the required information on drug use and ADR was not available in the electronic medical record and patients with only one registered contact and no further followup at the outpatient clinic were excluded. The difference in the incidence and type of ADR between male and female IBD patients were analyzed statistically by χ2 test. RESULTS: In total, 1009 IBD patients were identifed in the electronic diagnosis registration syst