The intestinal microbiota plays a fundamental role in maintaining immune homeostasis. In controlled clinical trials probiotic bacteria have demonstrated a benefit in treating gastrointestinal ...diseases, including infectious diarrhea in children, recurrent Clostridium difficile‐induced infection, and some inflammatory bowel diseases. This evidence has led to the proof of principle that probiotic bacteria can be used as a therapeutic strategy to ameliorate human diseases. The precise mechanisms influencing the crosstalk between the microbe and the host remain unclear but there is growing evidence to suggest that the functioning of the immune system at both a systemic and a mucosal level can be modulated by bacteria in the gut. Recent compelling evidence has demonstrated that manipulating the microbiota can influence the host. Several new mechanisms by which probiotics exert their beneficial effects have been identified and it is now clear that significant differences exist between different probiotic bacterial species and strains; organisms need to be selected in a more rational manner to treat disease. Mechanisms contributing to altered immune function in vivo induced by probiotic bacteria may include modulation of the microbiota itself, improved barrier function with consequent reduction in immune exposure to microbiota, and direct effects of bacteria on different epithelial and immune cell types. These effects are discussed with an emphasis on those organisms that have been used to treat human inflammatory bowel diseases in controlled clinical trials.
(Inflamm Bowel Dis 2008)
Background and aim: Evidence exists for the pathogenic role of the enteric flora in inflammatory bowel disease. Probiotics contain living microorganisms which exert health effects on the host. We ...compared the efficacy in maintaining remission of the probiotic preparation Escherichia coli Nissle 1917 and established therapy with mesalazine in patients with ulcerative colitis. Patients and methods: In total, 327 patients were recruited and assigned to a double blind, double dummy trial to receive either the probiotic drug 200 mg once daily (n = 162) or mesalazine 500 mg three times daily (n = 165). The study lasted for 12 months and patients were assessed by clinical and endoscopic activity indices (Rachmilewitz) as well as by histology. The primary aim of the study was to confirm equivalent efficacy of the two drugs in the prevention of relapses. Results: The per protocol analysis revealed relapses in 40/110 (36.4%) patients in the E coli Nissle 1917 group and 38/112 (33.9%) in the mesalazine group (significant equivalence p = 0.003). Subgroup analyses showed no differences between the treatment groups in terms of duration and localisation of disease or pretrial treatment. Safety profile and tolerability were very good for both groups and were not different. Conclusions: The probiotic drug E coli Nissle 1917 shows efficacy and safety in maintaining remission equivalent to the gold standard mesalazine in patients with ulcerative colitis. The effectiveness of probiotic treatment further underlines the pathogenetic significance of the enteric flora.
Aliment Pharmacol Ther 2011; 34: 113–124
Summary
Background There is no international agreement on scoring systems used to measure disease activity in ulcerative colitis, nor is there a validated ...definition for disease remission.
Aim To review the principles and components for defining remission in ulcerative colitis and propose a definition that will help improve patient outcomes.
Methods A review of current standards of remission from the perspective of clinical trials, guidelines, clinical practice and patients was conducted by the authors. Selected literature focused on the components of a definition of remission, the utility of a definition and treatment strategies, based on current definitions.
Results Different definitions of remission affect the assessment of outcome and make it difficult to compare trials. In the clinic, endoscopy is rarely used to confirm remission, because mucosal healing has only recently begun to be related to the duration of subsequent remission in a way that will affect clinical practice. Histopathology may be the ultimate arbiter of mucosal healing. There is no agreement on the definition of remission in current guidelines. Patient‐defined remission may predict endoscopic remission, but has yet to be shown to predict duration of remission.
Conclusions A standard based on clinical symptoms and endoscopy is proposed. Histopathology is a third dimension of remission that may have prognostic value. The definition of remission should help predict long‐term outcome. The expectations of patients and their physicians need to be raised, as the goal of treatment of active ulcerative colitis should be to induce remission.
Background Although constipation can be a chronic and severe problem, it is largely treated empirically. Evidence for the efficacy of some of the older laxatives from well‐designed trials is ...limited. Patients often report high levels of dissatisfaction with their treatment, which is attributed to a lack of efficacy or unpleasant side‐effects. Management guidelines and recommendations are limited and are not sufficiently current to include treatments that became available more recently, such as prokinetic agents in Europe.
Purpose We present an overview of the pathophysiology, diagnosis, current management and available guidelines for the treatment of chronic constipation, and include recent data on the efficacy and potential clinical use of the more newly available therapeutic agents. Based on published algorithms and guidelines on the management of chronic constipation, secondary pathologies and causes are first excluded and then diet, lifestyle, and, if available, behavioral measures adopted. If these fail, bulk‐forming, osmotic, and stimulant laxatives can be used. If symptoms are not satisfactorily resolved, a prokinetic agent such as prucalopride can be prescribed. Biofeedback is recommended as a treatment for chronic constipation in patients with disordered defecation. Surgery should only be considered once all other treatment options have been exhausted.
Pumps are critical life-sustaining components for all animals. At the earliest stages of life, the tubular embryonic heart works as a valveless pump capable of generating unidirectional blood flow. ...Inspired by this elementary pump, we developed an example of a biohybrid valveless pump-bot powered by engineered skeletal muscle. Our pump-bot consists of a soft hydrogel tube connected at both ends to a stiffer polydimethylsiloxane (PDMS) scaffold, creating an impedance mismatch. A contractile muscle ring wraps around the hydrogel tube at an off-center location, squeezing the tube with or without buckling it locally. Cyclic muscle contractions, spontaneous or electrically stimulated, further squeeze the tube, resulting in elastic waves that propagate along the soft tube and get reflected back at the soft/stiff tube boundaries. Asymmetric placement of muscle ring results in a time delay between the wave arrivals, thus establishing a net unidirectional fluid flow irrespective of whether the tube is buckled or not. Flow rates of up to 22.5 μL/min are achieved by the present pump-bot, which are at least three orders of magnitude higher than those from cardiomyocyte-powered valve pumps of similar size. Owning to its simple geometry, robustness, ease of fabrication, and high pumping performance, our pump-bot is particularly well-suited for a wide range of biomedical applications in microfluidics, drug delivery, biomedical devices, cardiovascular pumping system, and more.
Background: Diabetic gastroparesis is a disabling condition with no consistently effective treatment. In animals, ghrelin increases gastric emptying and reverses postoperative ileus. We present the ...results of a double blind, placebo controlled, crossover study of ghrelin in gastric emptying in patients with diabetic gastroparesis. Methods: Ten insulin requiring diabetic patients (five men, six type I) referred with symptoms indicative of gastroparesis received a two hour infusion of either ghrelin (5 pmol/kg/min) or saline on two occasions. Blood glucose was controlled by euglycaemic clamp. Gastric emptying rate (GER) was calculated by real time ultrasound following a test meal. Blood was sampled for ghrelin, growth hormone (GH), and pancreatic polypeptide (PP) levels. Cardiovagal neuropathy was assessed using the Mayo Clinic composite autonomic severity score (range 0 (normal)–3). Results: Baseline ghrelin levels were mean 445 (SEM 36) pmol/l. Ghrelin infusion achieved a peak plasma level of 2786 (188) pmol/l at 90 minutes, corresponding to a peak GH of 70.9 (19.8) pmol/l. Ghrelin increased gastric emptying in seven of 10 patients (30 (6)% to 43 (5)%; p = 0.04). Impaired cardiovagal tone correlated inversely with peak postprandial PP values (p<0.05) but did not correlate with GER. Conclusions: Ghrelin increases gastric emptying in patients with diabetic gastroparesis. This is independent of vagal tone. We propose that analogues of ghrelin may represent a new class of prokinetic agents.
To evaluate the efficacy of adalimumab in the healing of draining fistulas in patients with active Crohn's disease (CD).
A phase III, multicentre, randomised, double-blind, placebo controlled study ...with an open-label extension was conducted in 92 sites.
A subgroup of adults with moderate to severely active CD (CD activity index 220-450) for >or=4 months who had draining fistulas at baseline.
All patients received initial open-label adalimumab induction therapy (80 mg/40 mg at weeks 0/2). At week 4, all patients were randomly assigned to receive double-blind placebo or adalimumab 40 mg every other week or weekly to week 56 (irrespective of fistula status). Patients completing week 56 of therapy were then eligible to enroll in an open-label extension.
Complete fistula healing/closure (assessed at every visit) was defined as no drainage, either spontaneous or with gentle compression.
Of 854 patients enrolled, 117 had draining fistulas at both screening and baseline (70 randomly assigned to adalimumab and 47 to placebo). The mean number of draining fistulas per day was significantly decreased in adalimumab-treated patients compared with placebo-treated patients during the double-blind treatment period. Of all patients with healed fistulas at week 56 (both adalimumab and placebo groups), 90% (28/31) maintained healing following 1 year of open-label adalimumab therapy (observed analysis).
In patients with active CD, adalimumab therapy was more effective than placebo for inducing fistula healing. Complete fistula healing was sustained for up to 2 years by most patients in an open-label extension trial.
Aliment Pharmacol Ther 2012; 35: 48–55
Summary
Background Chronic intestinal pseudo‐obstruction is a disabling condition for which there are no established drug therapies. The condition is caused by ...a diverse range of intestinal myopathies and neuropathies.
Aim To assess the therapeutic efficacy of prucalopride, a selective high‐affinity 5‐HT4 receptor agonist, we employed a multiple n = 1 study design. Each patient acted as his/her own control, each day counting as one treatment episode, allowing comparison of 168 days on each of active drug and placebo.
Methods Double‐blind, randomised, placebo‐controlled, cross‐over trial of four 12‐week treatment periods, with 2–4 mg prucalopride or placebo daily. In each of the first and second 6 months there was a prucalopride and a placebo treatment. Patients with proven chronic intestinal pseudo‐obstruction, including dilated gut, were included. Evaluation was by patient diary and global evaluation.
Results Seven patients participated (mean 42 years, five female, median symptom duration 11 years). Three discontinued, two due to study length, and one on prucalopride due to unrelated malnutrition and bronchopneumonia. Four patients (three visceral myopathy and one visceral neuropathy) completed the study; prucalopride significantly improved pain in three of four patients, nausea in two, vomiting in one, bloating in four and analgesic intake. Bowel function was not changed substantially.
Conclusions n = 1 studies in rare conditions allow drug efficacy assessment. Prucalopride relieves symptoms in selected patients with chronic pseudo‐obstruction.
Summary
Background The impact of constipation on quality of life (QoL) may vary in different cultural or national settings.
Aim We studied QoL in a multinational survey to compare different social ...and demographic groups with and without constipation (defined according to Rome III criteria) and to detect country‐specific differences among the groups studied.
Methods Health‐related QoL (HRQoL) was assessed with the Short Form 36 (SF‐36) questionnaire in 2870 subjects in France, Germany, Italy, UK, South Korea, Brazil and USA.
Results Respondents were mainly middle‐aged, married or living together and part‐ or full‐time employed. General health status, measured by the SF‐36 questionnaire, was significantly worse in the constipated vs. non‐constipated populations. Results were comparable in all countries. QoL scores correlated negatively with age. Constipated women reported more impaired HRQoL than constipated men. Brazilians were most affected by constipation as to their social functioning (35.8 constipated vs. 51.3 non‐constipated) and general health perception (29.4 constipated vs. 54.4 non‐constipated).
Conclusions There are significant differences in HRQoL between constipated and non‐constipated individuals and a significant, negative correlation between the number of symptoms and complaints and SF‐36 scores. The study detected a correlation of constipation with QoL and the influence of social and demographic factors on HRQoL in constipated people.
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