Speedometer for withdrawal time monitoring during colonoscopy: a clinical implementation trial.

OBJECTIVES: Meticulous inspection of the mucosa during colonoscopy, represents a lengthier withdrawal time, but has been shown to increase adenoma detection rate (ADR). We investigated if artificial intelligence-aided speed monitoring can improve suboptimal withdrawal time. METHODS: We evaluated the implementation of a computer-aided speed monitoring device during colonoscopy at a large academic endoscopy center. After informed consent, patients ≥18 years undergoing colonoscopy between 5 March and 29 April 2021 were examined without the use of the speedometer, and with the speedometer between 29 April and 30 June 2021. All colonoscopies were recorded, and withdrawal time was assessed based on the recordings in a blinded fashion. We compared mean withdrawal time, percentage of withdrawal time ≥6 min, and ADR with and without the speedometer. RESULTS: One hundred sixty-six patients in each group were eligible for analyses. Mean withdrawal time was 9 min and 6.6 s (95% CI: 8 min and 34.8 s to 9 min and 39 s) without the use of the speedometer, and 9 min and 9 s (95% CI: 8 min and 45 s to 9 min and 33.6 s) with the speedometer; difference 2.3 s (95% CI: -42.3-37.7, p = 0.91). The ADRs were 45.2% (95% CI: 37.6-52.8) without the speedometer as compared to 45.8% (95% CI: 38.2-53.4) with the speedometer (p = 0.91). The proportion of colonoscopies with withdrawal time ≥6 min without the speedometer was 85.5% (95% CI: 80.2-90.9) versus 86.7% (95% CI: 81.6-91.9) with the speedometer (p = 0.75). CONCLUSIONS: Use of speed monitoring during withdrawal did not increase withdrawal time or ADR in colonoscopy. CLINICALTRIALS.GOV IDENTIFIER: NCT04710251.

The Association between Serum 25-Hydroxyvitamin D and Cancer Risk: Results from the Prospective KORA F4 Study.

BACKGROUND: Many studies have examined the relationship between vitamin D and specific types of cancer with inconsistent results. Furthermore, to date, no observational studies have demonstrated a clear relationship between vitamin D and total cancer risk. METHODS: We analyzed data from a population-based prospective cohort study including 2,003 initially cancer-free participants from the KORA F4 study with baseline serum 25-hydroxyvitamin D (25(OH)D) measurements (surveyed between 2006 and 2008). We used Cox proportional hazard models to assess the association between 25(OH)D levels and incident cancer risk. RESULTS: Within a follow-up period of 7 years, 69 of the participants developed cancer. Overall, we observed no significant relationship between serum 25(OH)D levels and cancer risk. The hazard ratio (HR) per 1 ng/ml increase in 25 (OH)D for this relationship was 1.00 (95% confidence interval (CI) 0.97-1.04) adjusting for age, sex, body mass index, and season of blood draw. This was also true in subgroup analysis for prostate cancer (HR 0.95, 95% CI 0.88-1.03), breast cancer (HR 1.03, 95% CI 0.97-1.09), and colorectal cancer (HR 0.97, 95% CI 0.88-1.07). CONCLUSION: Our study found no protective effect of 25(OH)D against developing cancer. However, studies with more participants and additional measurements of 25(OH)D are still needed to accurately clarify the relationship between 25(OH)D and total cancer risk.

Cutting edge: Compartmentalization of Th1-like noninvariant CD1d-reactive T cells in hepatitis C virus-infected liver.

Murine intrahepatic lymphocytes (IHL) are dominated by invariant TCR alpha-chain expressing CD1d-reactive NKT cells, which can cause model hepatitis. Invariant NKT (CD56(+/-)CD161(+)) and recently identified noninvariant CD1d-reactive T cells rapidly produce large amounts of IL-4 and/or IFN-gamma and can regulate Th1/Th2 responses. Human liver contains large numbers of CD56(+) NKT cells but few invariant NKT. Compared with matched peripheral blood T cell lines, primary IHL lines from patients with chronic hepatitis C had high levels of CD161 and CD1d reactivity, but the invariant TCR was rare. CD1d-reactive IHL were strikingly Th1 biased. IHL also demonstrated CD1d-specific cytotoxic activity. Hepatocytes and other liver cells express CD1d. These results identify a novel population of human T cells that could contribute to destructive as well as protective immune responses in the liver. CD1d-reactive T cells may have distinct roles in different tissues.