Comparison of the implantation and metabolic activity of human and rat fecal flora administered to axenic rats

Gnotobiotic rodents are increasingly used as a model for studying in vivo the characteristics of human colonic flora. However, the value of this model has been poorly assessed. In this study fecal bacterial flora provided either by a conventional rat (group RFR) or by man (group RFH) was administered orally to two groups of 6 germ-free rats. One month later, quantitative bacteriological analyses of feces revealed that bacterial populations were close to those of donors in both groups. The metabolic activity of the genuine flora was further compared in groups RFR and RFH with that of the implanted flora: a) concentrations of each fecal volatile fatty acid and of fecal bile acids were similar in conventional and RFR rats as well as the percentage of transformation of cholesterol into coprostanol (48 p. 100 and 54 +/- 5 p. 100 respectively; m +/- SD); b) similar concentrations of fecal volatile fatty acids were obtained from the human donor and RFH rats. Alpha, beta and omega muricholic acids absent in human donor's feces were found in RFH feces. Cholesterol transformation was lower in RFH rats (48 +/- 9 p. 100) than in man (85 p. 100); c) a single dose of lactulose (3 g/kg) increased breath hydrogen excretion in man but not in conventional or in RFR rats and RFH. Chronic lactulose ingestion (3 g/kg d.i.b. for 8 days) had no effect in conventional or RFR rats. Hydrogen excretion was decreased in man, whereas it was significantly increased in RFH rats.(ABSTRACT TRUNCATED AT 250 WORDS)     

PAF-acether and acetylhydrolase in stool of patients with Crohn's disease

PAF-acether (PAF) is a phospholipid mediator with potent biological effects on the digestive tract. We report the presence of PAF in stool of patients with active Crohn's disease (39.1±13.5 ng/g of stool, mean ±sem,N=19) and its absence in patients with irritable bowel syndrome with diarrhea and diarrhea with malabsorption. Fecal PAF acetylhydrolase activity was higher (P<0.04) in patients with Crohn's disease as compared to patients with irritable bowel syndrome with diarrhea and diarrhea with malabsorption. We also report a solid-phase extraction of fecal PAF using silica minicolumns, which yielded results highly correlated with those obtained with a highperformance liquid chromatography method (r=0.86,P<0.001,N=16). These findings may allow us to implicate PAF in the onset and perpetuation of digestive tract inflammatory symptoms observed during Crohn's disease. They would warrant to investigate the influence of various therapeutic agents, including PAF antagonists, on fecal PAF levels during inflammatory digestive ailments.This study was supported by grant 91CN 12 from INSERM.     

Value of spiral automatic plating in quantitative bacteriology

The Spiral plate count method, semi-automated plating technique, presents some advantages: saving of time and materials, fast and easy counting. This method appears well adapted for studies of microbial ecology.     

The effect of ofloxacin on bacillus calmette-guerin induced toxicity in patients with superficial bladder cancer: results of a randomized, prospective, double-blind, placebo controlled, multicenter study

PURPOSE: We determined whether prophylaxis with ofloxacin could decrease the toxicity of bacillus Calmette-Guerin for transitional cell carcinoma of the bladder. We also investigated the impact of ofloxacin on bacillus Calmette-Guerin antitumor efficacy. MATERIALS AND METHODS: In this randomized, double-blind, multicenter study 115 patients with primary or recurrent superficial bladder cancer (Ta/T1, CIS, G1-G3) and no prior bacillus Calmette-Guerin treatment were randomized to induction treatment with intravesical bacillus Calmette-Guerin (6 plus 3 instillations) plus 200 mg ofloxacin in group 1 or plus placebo in group 2. Adverse events were assessed using a detailed grid of classification for bacillus Calmette-Guerin related adverse events. Mean patient age +/- SD was 65.6 +/- 10.4 years in the 57 group 1 patients and 65.7 +/- 8.7 years in the 58 in group 2. Median followup was 369 and 374 days in groups 1 and 2, respectively. RESULTS: Ofloxacin significantly decreased by 18.5% the incidence of class II or higher moderate and severe adverse events between instillations 4 and 6. The percent of class III adverse events was significantly decreased by ofloxacin between instillations 1 and 9. Although ofloxacin decreased adverse events involving the lower urinary tract, it did not prevent class I adverse events. Compliance with full bacillus Calmette-Guerin treatment was also improved. Of patients in group 1, 80.7% received 9 instillations compared with 65.5% in group 2 (p = 0.092). At 12 months recurrence and progression rates in group 1 and 2 were 12.7% and 17.2%, and 5.5% and 1.7%, respectively. CONCLUSIONS: Prophylactic ofloxacin decreased the incidence of moderate to severe adverse events associated with bacillus Calmette-Guerin intravesical therapy, particularly class III events, which are primarily associated with patient dropout. Compliance with induction and maintenance therapy may be improved by adjuvant ofloxacin therapy. However, long-term comparative studies with other preventive strategies must be done to confirm these initial findings with compliance and recurrence-free survival as the primary end points.     

Rapid identification of mycobacteria and drug-resistant Mycobacterium tuberculosis by use of a single multiplex PCR and DNA sequencing

Tuberculosis (TB) remains a significant global health problem for which rapid diagnosis is critical to both treatment and control. This report describes a multiplex PCR method, the Mycobacterial IDentification and Drug Resistance Screen (MID-DRS) assay, which allows identification of members of the Mycobacterium tuberculosis complex (MTBC) and the simultaneous amplification of targets for sequencing-based drug resistance screening of rifampin-resistant (rifampin(r)), isoniazid(r), and pyrazinamide(r) TB. Additionally, the same multiplex reaction amplifies a specific 16S rRNA gene target for rapid identification of M. avium complex (MAC) and a region of the heat shock protein 65 gene (hsp65) for further DNA sequencing-based confirmation or identification of other mycobacterial species. Comparison of preliminary results generated with MID-DRS versus culture-based methods for a total of 188 bacterial isolates demonstrated MID-DRS sensitivity and specificity as 100% and 96.8% for MTBC identification; 100% and 98.3% for MAC identification; 97.4% and 98.7% for rifampin(r) TB identification; 60.6% and 100% for isoniazid(r) TB identification; and 75.0% and 98.1% for pyrazinamide(r) TB identification. The performance of the MID-DRS was also tested on acid-fast-bacterium (AFB)-positive clinical specimens, resulting in sensitivity and specificity of 100% and 78.6% for detection of MTBC and 100% and 97.8% for detection of MAC. In conclusion, use of the MID-DRS reduces the time necessary for initial identification and drug resistance screening of TB specimens to as little as 2 days. Since all targets needed for completing the assay are included in a single PCR amplification step, assay costs, preparation time, and risks due to user errors are also reduced.     

Efficacy of the InVance male sling in men with stress urinary incontinence

OBJECTIVES: To evaluate the efficacy and safety of the InVance bulbourethral sling in male stress urinary incontinence. MATERIALS AND METHODS: Between June 2003 and April 2005, the InVance bulbourethral sling was implanted into 50 patients with urinary incontinence after prostate surgery in 49 cases and pelvic trauma in 1 case. The patients were monitored and evaluated in a prospective manner (continence, tolerance, and satisfaction). The treatment was considered to be successful if the patient stopped wearing any kind of continence pad (patient cured) or only one pad per day (patient improved), with no de novo urinary disorders and without significant postvoid residual urine. Patient satisfaction with the procedure was assessed. RESULTS: After a median follow-up of 6 mo, 50% of patients were dry, 26% had improved, and 24% suffered treatment failure. The success rates for the patients with severe incontinence and those who had undergone radiation therapy were 50% and 25%, respectively. All patients who were dry or had improved were satisfied and presented no obstructive or irritative de novo urinary disorders. The overall success rate for the 51 procedures conducted was 74.5%. Six cases of transitory acute urine retention and six cases of persistent perineal pain were reported. Explantation was necessary because of suppuration of the sling in three patients and of a de novo irritative urinary disorder in one patient. No cases of pubic osteitis or urethral erosion were reported. CONCLUSIONS: The InVance bulbourethral sling procedure makes it possible to treat stress urinary incontinence after prostate surgery with satisfactory and lasting short-term results. Severe incontinence and a past history of pelvic radiation therapy seem to be factors contributing to the failure of this procedure.     

Infliximab plus azathioprine for steroid-dependent Crohn's disease patients: a randomized placebo-controlled trial

BACKGROUND & AIMS: The aim of this study was to evaluate the usefulness of short-term infliximab combined with azathioprine (AZA) or 6-mercaptopurine (6-MP) in steroid-dependent Crohn's disease patients. METHODS: Patients with active disease despite prednisone given for more than 6 months were eligible and were stratified as follows: the failure stratum consisted of patients receiving AZA/6-MP at a stable dose for more than 6 months, and the naive stratum consisted of patients not treated previously with AZA/6-MP. Patients were randomized to infliximab 5 mg/kg or placebo at weeks 0, 2, and 6. All patients were treated with AZA/6-MP maintained at a stable dose throughout the 52 weeks of the study. The primary end point was remission off steroids at week 24. RESULTS: Among the 113 enrolled patients (55 in the failure stratum), 57 were assigned to infliximab. At week 24, the success rate (intent-to-treat analysis) was higher in the infliximab group than in the placebo group (57% vs 29%; P = .003); at weeks 12 and 52, the corresponding rates were 75% vs 38% (P < .001) and 40% vs 22% (P = .04), respectively. In each stratum, the success rate was significantly higher in the infliximab group at weeks 12 and 24, and a trend was found at week 52. In the failure stratum, only 27% of the patients in the infliximab group were still in remission off steroids, compared with 52% in the naive stratum. Steroid resistance was less common and the cumulative dose of prednisone was lower in the infliximab group. CONCLUSIONS: Infliximab plus AZA/6-MP is more effective than AZA/6-MP alone in steroid-dependent Crohn's disease patients.