A simple cage-autonomous method for the maintenance of the barrier status of germ-free mice during experimentation.

The use of germ-free (GF) isolators for microbiome-related research is exponentially increasing, yet limited by its cost, isolator size and potential for trans-contamination. As such, current isolator technology is highly limiting to researchers engaged in short period experiments involving multiple mouse strains and employing a variety of mono-inoculated microorganisms. In this study, we evaluate the use of positive pressure Isocages as a solution for short period studies (days to 2-3 weeks) of experimentation with GF mice at multiple simultaneous conditions. We demonstrate that this new Isocage technology is cost-effective and room-sparing, and enables maintenance of multiple simultaneous groups of GF mice. Using this technology, transferring GF mice from isolators to Isocage racks for experimentation, where they are kept under fully germ-free conditions, enables parallel inoculation with different bacterial strains and simultaneous experimentation with multiple research conditions. Altogether, the new GF Isocage technology enables the expansion of GF capabilities in a safe and cost-effective manner that can facilitate the growth, elaboration and flexibility of microbiome research.

Stress and exacerbation in ulcerative colitis: a prospective study of patients enrolled in remission.

OBJECTIVE: We sought to determine whether psychosocial factors influence the course of ulcerative colitis, hypothesizing that high perceived stress among patients with inactive disease will increase the risk of subsequent exacerbation. METHODS: Sixty-two patients with known ulcerative colitis were enrolled into a prospective cohort study while in clinical remission. Their perceived stress, depressive symptoms, and stressful life events were followed, along with potential confounders, for up to 45 months; exacerbation status was monitored for up to 68 months. RESULTS: The 27 patients who experienced an exacerbation were compared with those who remained in remission. Having a score in the upper tertile on the long-term (past 2 yr) baseline Perceived Stress Questionnaire significantly increased the actuarial risk of exacerbation (hazards ratio = 2.8, 95% confidence interval 1.1-7.2). At any given study visit, high long-term stress tripled the risk of exacerbation during the next 8 months (risk for the three tertiles, 8.3%, 16.7%, and 26.2%, p = 0.02). Shorter sleep time, briefer remission, histological activity, and use of nonsteroidal antiinflammatory drugs, antibiotics, or oral contraceptives also increased the medium- and/or long-term risk of exacerbation, but adjustment for these variables did not eliminate the associations with stress. Exacerbation was not associated with stressful life events, depressive symptoms, short-term (past month) perceived stress, smoking, disease extent or duration, or severity of recent course. CONCLUSIONS: Short-term stress does not trigger exacerbation in ulcerative colitis, but long-term perceived stress increases the risk of exacerbation over a period of months to years.

Prospective evaluation of transabdominal bowel sonography in the diagnosis of intestinal obstruction in Crohn's disease: comparison with plain abdominal film and small bowel enteroclysis.

Transabdominal ultrasonography is a noninvasive, radiation-free method that is well tolerated by patients with acute abdominal symptoms. The aim of this study was to investigate the validity of transabdominal ultrasonography, compared with plain abdominal film and small bowel enteroclysis in the diagnosis of small bowel obstruction in patients with Crohn's disease (CD). Forty-four patients with CD ileitis or ileocolitis and acute obstructive symptoms who received ultrasonography and plain abdominal film at hospital admission were evaluated by small bowel enema before dismissal or surgery and were considered for statistical analysis. Small bowel obstruction was diagnosed by ultrasonography in 23 of 44 patients (52%), by plain abdominal film in 26 of 44 patients (59%), and by small bowel enema in 28 of 44 patients (64%); the diagnostic accuracy of plain abdominal film and ultrasonography compared with small bowel enema was 73% and 89%, respectively. Ultrasonography proved to be highly specific (100%) with no false positive results. Surgery performed in 25 of 44 patients for symptoms refractory to medical treatment confirmed the high diagnostic value of ultrasonography. The result of this study indicates that transabdominal ultrasonography is accurate and highly specific in the diagnosis of small bowel obstruction and can be considered a valuable first choice examination in CD patients with obstructive symptoms.

Microbiologically monitored fumigation of a newly built SPF laboratory rodent facility.

The initial sanitization and sterilization of a newly built animal facility for the breeding and holding of specific pathogen free (SPF) rats and mice is described. The fumigation programme was started with methyl bromide treatment directed primarily against arthropods, followed by ammonia spray to kill coccidial oocysts and concluded by three formaldehyde treatments with fog and spray against bacteria and viruses. The practicalities and problems involved are described in detail and the rationale and purpose of the programme and its monitoring are discussed. The report is expected to contribute towards the establishment of a rational, efficient and standardized fumigation programme for SPF animal facilities, under increasing constraints of safety and environmental considerations concerning pollution with toxic and corrosive agents.