G-EYE colonoscopy is superior to standard colonoscopy for increasing adenoma detection rate: an international randomized controlled trial (with videos).

BACKGROUND AND AIMS: Colorectal cancer (CRC) is largely preventable with routine screening and surveillance colonoscopy; however, interval cancers arising from precancerous lesions missed by standard colonoscopy still occur. An increased adenoma detection rate (ADR) has been found to be inversely associated with interval cancers. The G-EYE device includes a reusable balloon integrated at the distal tip of a standard colonoscope, which flattens haustral folds, centralizes the colonoscope's optics, and reduces bowel slippage. The insufflated balloon also aims to enhance visualization of the colon during withdrawal, thereby increasing the ADR. METHODS: In this randomized, controlled, international, multicenter study (11 centers), patients (aged ≥50 years) referred to colonoscopy for screening, surveillance, or changes in bowel habits were randomized to undergo either balloon-assisted colonoscopy by using an insufflated balloon during withdrawal or standard high-definition colonoscopy. The primary endpoint was the ADR. RESULTS: One thousand patients were enrolled between May 2014 and September 2016 to undergo colonoscopy by experienced endoscopists; 803 were finally analyzed (standard colonoscopy n = 396; balloon-assisted colonoscopy n = 407). Baseline parameters were similar in both groups. Balloon-assisted colonoscopy provided a 48.0% ADR compared with 37.5% in the standard colonoscopy group (28% increase; P = .0027). Additionally, balloon-assisted colonoscopy provided for a significant increase in detection of advanced (P = .0033) flat adenomas (P < .0001) and sessile serrated adenomas/polyps (P = .0026). CONCLUSION: Balloon-assisted colonoscopy yielded a higher ADR and increased the detection of advanced, flat, and sessile serrated adenomas/polyps when compared with standard colonoscopy. Improved detection by the G-EYE device could impact the quality of CRC screening by reducing miss rates and consequently reducing interval cancer incidence. (Clinical trial registration number: NCT01917513.).

Inactivation of photosynthetic electron flow during desiccation of desert biological sand crusts and Microcoleus sp.-enriched isolates.

Filamentous cyanobacteria, the main primary producers in biological sand crusts, survive harsh environmental conditions including diurnal desiccation/rehydration cycles. Here we describe the inactivation of photosystem II during dehydration of native crusts (NC) and Microcoleus sp. isolates grown on nitrocellulose filters (NCF). The morphology of NCF cells, visualized by scanning-transmission and atomic-force microscopy, disclosed long bacterial filaments encapsulated in extracellular polysaccharides (EPS) tubes consisting of parallel fibrils (100-400 nm wide and 50-100 nm high) oriented mostly perpendicular to the tube length. Presence of empty EPS tubes indicated a gliding capability of the cells. Desiccation of NC resulted in a rapid decline of F(o) and complete loss of F(v). These changes were accompanied by a decrease of 77 K PSII fluorescence emission relative to that of PSI, when excited at 430 nm, and a significant decrease of energy transfer from phycobilisomes to PSII. Lowering the turgor pressure through the addition of 1.5 M trehalose to natural crusts, reduced F(v)/F(m) by over 50% and was accompanied by a decrease of 77 K PSI fluorescence induced by chlorophyll excitation. Excitation of phycobilisomes resulted in a downshift of the PSI emission wavelength by 8 nm, indicative of reduced energy transfer from LHCI to the core PSI. Decline of F(v)/F(m) in trehalose-incubated NCF cells did not induce significant changes in 77 K fluorescence emission. These results suggest that alterations in energy transfer from antennae to reaction centers may be part of the survival strategy of Microcoleus.