Lubiprostone Decreases the Small Bowel Transit Time by Capsule Endoscopy: An Exploratory, Randomised, Double-Blind, Placebo-Controlled 3-Way Crossover Study

The aim of this study was to investigate the usefulness of lubiprostone for bowel preparation and as a propulsive agent in small bowel endoscopy. Six healthy male volunteers participated in this randomized, 3-way crossover study. The subjects received a 24 μg tablet of lubiprostone 60 minutes prior to the capsule ingestion for capsule endoscopy (CE) and a placebo tablet 30 minutes before the capsule ingestion (L-P regimen), a placebo tablet 60 minutes prior to CE and a 24 μg tablet of lubiprostone 30 minutes prior to CE (P-L regimen), or a placebo tablet 60 minutes prior to r CE and a placebo tablet again 30 minutes prior to CE (P-P regimen). The quality of the capsule endoscopic images and the amount of water in the small bowel were assessed on 5-point scale. The median SBTT was 178.5 (117–407) minutes in the P-P regimen, 122.5 (27–282) minutes in the L-P regimen, and 110.5 (11–331) minutes in the P-L regimen (P=0.042). This study showed that the use of lubiprostone significantly decreased the SBTT. We also confirmed that lubiprostone was effective for inducing water secretion into the small bowel during CE

Metformin efficacy and safety for colorectal polyps: a double-blind randomized controlled trial

<p>Abstract</p> <p>Background</p> <p>Colorectal cancer is one of the major neoplasms and a leading cause of cancer death worldwide, and new preventive strategies are needed to lower the burden of this disease. Metformin, a biguanide, which is widely used for treating diabetes mellitus, has recently been suggestive to have a suppressive effect on tumorigenesis and cancer cell growth. In a previous study conducted in non-diabetic subjects, we showed that oral short-term low-dose metformin suppressed the development of colorectal aberrant crypt foci (ACF). ACF have been considered as a useful surrogate biomarker of CRC, although the biological significance of these lesions remains controversial. We devised a prospective randomized controlled trial to evaluate the chemopreventive effect of metformin against metachronous colorectal polyps and the safety of this drug in non-diabetic post-polypectomy patients.</p> <p>Methods/Design</p> <p>This study is a multi-center, double-blind, placebo-controlled, randomized controlled trial to be conducted in non-diabetic patients with a recent history of undergoing colorectal polypectomy. All adult patients visiting the Yokohama City University hospital or affiliated hospitals for polypectomy shall be recruited for the study. Eligible patients will then be allocated randomly into either one of two groups: the metformin group and the placebo group. Patients in the metformin group shall receive oral metformin at 250 mg per day, and those in the placebo group shall receive an oral placebo tablet. At the end of 1 year of administration of metformin/placebo, colonoscopy will be performed to evaluate the polyp formation.</p> <p>Discussion</p> <p>This is the first study proposed to explore the effect of metformin against colorectal polyp formation. Metformin activates AMPK, which inhibits the mammalian target of rapamycin (mTOR) pathway. The mTOR pathway plays an important role in the cellular protein translational machinery and cell proliferation. Patients with type 2 diabetes taking under treatment with metformin have been reported to be at a lower risk of cancer development than those not taking under treatment with metformin. We showed in a previous study that metformin suppressed the formation of human colorectal ACF. We therefore decided to conduct a study to determine whether metformin might suppress the formation of human colorectal polyps.</p> <p>Trial registration</p> <p>This trial has been registered in the University hospital Medical Information Network (UMIN) Clinical Trials Registry as <a href="http://www.clinicaltrials.gov/ct2/show/UMIN000006254">UMIN000006254</a></p

Investigation of Small Bowel Abnormalities in HIV-Infected Patients Using Capsule Endoscopy

HIV infection is reportedly associated with an increased permeability of the intestinal epithelium and can cause HIV enteropathy, which occurs independently of opportunistic infections. However, the characteristics of small bowel abnormalities attributable to HIV infection are rarely investigated. In the present study, we assessed the intestinal mucosal changes found in HIV-infected patients and compared them with the mucosa of healthy control subjects using capsule endoscopy (CE). Three of the 27 HIV-infected patients harbored gastrointestinal opportunistic infections and were thus excluded from subsequent analyses. The endoscopic findings of CE in HIV-infected patients were significantly higher than those in control subjects (55% versus 10%, P=0.002); however, most lesions, such as red spots or tiny erosions, were unlikely to cause abdominal symptoms. After validating the efficacy of CE for the diagnosis of villous atrophy, we found that the prevalence of villous atrophy was 54% (13/24) among HIV-infected patients. Interestingly, villous atrophy persisted in patients receiving long-term antiretroviral therapy, though most of them exhibited reconstituted peripheral blood CD4+ T cells. Although we could not draw any conclusions regarding the development of small bowel abnormalities in HIV-infected patients, our results may provide some insight regarding the pathogenesis of HIV enteropathy

Large variation in carbon dioxide emissions from tropical peat swamp forests due to disturbances

Abstract The huge carbon stock of tropical peat swamp forest (PSF) in Southeast Asia has been threatened by environmental disturbances due to quasi-periodic El Niño-Southern Oscillation (ENSO) droughts, biomass and peat burning, smoke haze, drainage, and deforestation. Carbon dioxide (CO2) emissions from such disturbances have not been well quantified because of insufficient field data. Therefore, we quantified the ecosystem-scale CO2 balance and examine the disturbance effects from a long-term field experiment for 12–15 years at three PSF sites with different degrees of degradation in Indonesia. Here, we show a drastic change of an undrained PSF from a CO2 sink to a source owing to the transient groundwater lowering by the droughts, a significant decrease in ecosystem photosynthesis due to the radiation attenuation by smoke haze in drought years, and long-lasting CO2 emissions through enhanced peat decomposition by drainage. The impact on CO2 emissions was greater from drainage than drought-induced disturbances