Narrow-band imaging versus white light for the detection of proximal colon serrated lesions: a randomized, controlled trial.

BACKGROUND: The value of narrow-band imaging (NBI) for detecting serrated lesions is unknown. OBJECTIVE: To assess NBI for the detection of proximal colon serrated lesions. DESIGN: Randomized, controlled trial. SETTING: Two academic hospital outpatient units. PATIENTS: Eight hundred outpatients 50 years of age and older with intact colons undergoing routine screening, surveillance, or diagnostic examinations. INTERVENTIONS: Randomization to colon inspection in NBI versus white-light colonoscopy. MAIN OUTCOME MEASUREMENTS: The number of serrated lesions (sessile serrated polyps plus hyperplastic polyps) proximal to the sigmoid colon. RESULTS: The mean inspection times for the whole colon and proximal colon were the same for the NBI and white-light groups. There were 204 proximal colon lesions in the NBI group and 158 in the white light group (P = .085). Detection of conventional adenomas was comparable in the 2 groups. LIMITATIONS: Lack of blinding, endoscopic estimation of polyp location. CONCLUSION: NBI may increase the detection of proximal colon serrated lesions, but the result in this trial did not reach significance. Additional study of this issue is warranted. ( CLINICAL TRIAL REGISTRATION NUMBER: NCT01572428.).

Skeletal macro- and microstructure adaptations in men undergoing arduous military training.

PURPOSE: Short periods of basic military training increase the density and size of the tibia, but the adaptive response of bone microarchitecture, a key component of bone strength, is not fully understood. METHODS: Tibial volumetric bone mineral density (vBMD), geometry, microarchitecture and mechanical properties were measured using high-resolution peripheral quantitative computed tomography in 43 male British Army infantry recruits (mean ±â€¯SD, age 21 ±â€¯3 years, height 1.76 ±â€¯0.06 m, body mass 76.5 ±â€¯9.4 kg). Bilateral scans were performed at the distal tibia at the start (week 1) and end (week 13) of basic military training. Concurrent measures were obtained for whole-body areal bone mineral density (aBMD) using DXA, and markers of bone metabolism (ßCTX, P1NP, PTH, total 25(OH)D and ACa) from venous blood. RESULTS: Training increased areal BMD for total body (1.4%) and arms (5.2%) (P ≤ 0.031), but not legs and trunk (P ≥ 0.094). Training increased trabecular (1.3 to 1.9%) and cortical vBMD (0.6 to 0.9%), trabecular volume (1.3 to 1.9%), cortical thickness (3.2 to 5.2%) and cortical area (2.6 to 2.8%), and reduced trabecular area (-0.4 to -0.5%) in both legs (P < 0.001). No changes in trabecular number, thickness and separation, cortical porosity, stiffness or failure load were observed (P ≥ 0.188). ßCTX decreased (-0.11 µg∙l-1, P < 0.001) and total 25(OH)D increased (9.4 nmol∙l-1, P = 0.029), but no differences in P1NP, PTH or ACa were observed between timepoints (P ≥ 0.233). CONCLUSION: A short period of basic military training increased density and altered geometry of the distal tibia in male military recruits. The osteogenic effects of basic military training are likely due to an increase in unaccustomed, dynamic and high-impact loading.