Reducing scope 3 carbon emissions in gastrointestinal endoscopy: results of the prospective study of the 'Green Endoscopy Project Würzburg'.

OBJECTIVE: Carbon emissions generated by gastrointestinal endoscopy have been recognised as a critical issue. Scope 3 emissions are mainly caused by the manufacturing, packaging and transportation of purchased goods. However, to our knowledge, there are no prospective data on the efficacy of measurements aimed to reduce scope 3 emissions. DESIGN: The study was performed in a medium-sized academic endoscopy unit. Manufacturers of endoscopic consumables were requested to answer a questionnaire on fabrication, origin, packaging and transport. Based on these data, alternative products were purchased whenever possible. In addition, staff was instructed on how to avoid waste. Thereafter, the carbon footprint of each item purchased was calculated from February to May 2023 (intervention period), and scope 3 emissions were compared with the same period of the previous year (control period). RESULTS: 26 of 40 companies answered the questionnaire. 229 of 322 products were classified as unfavourable. A switch to alternative items was possible for 47/229 items (20.5%). 1666 endoscopies were performed during the intervention period compared with 1751 examinations during the control period (-4.1%). The number of instruments used decreased by 10.0% (3111 vs 3457). Using fewer and alternative products resulted in 11.5% less carbon emissions (7.09 vs 8.01 tons of carbon equivalent=tCO2 e). Separation of waste led to a reduction of 20.1% (26.55 vs 33.24 tCO2e). In total, carbon emissions could be reduced by 18.4%. CONCLUSION: Use of fewer instruments per procedure, recycling packaging material and switching to alternative products can reduce carbon emissions without impairing the endoscopic workflow.

Artificial intelligence-based polyp size measurement in gastrointestinal endoscopy using the auxiliary waterjet as a reference.

BACKGROUND: Measurement of colorectal polyp size during endoscopy is mainly performed visually. In this work, we propose a novel polyp size measurement system (Poseidon) based on artificial intelligence (AI) using the auxiliary waterjet as a measurement reference. METHODS: Visual estimation, biopsy forceps-based estimation, and Poseidon were compared using a computed tomography colonography-based silicone model with 28 polyps of defined sizes. Four experienced gastroenterologists estimated polyp sizes visually and with biopsy forceps. Furthermore, the gastroenterologists recorded images of each polyp with the waterjet in proximity for the application of Poseidon. Additionally, Poseidon's measurements of 29 colorectal polyps during routine clinical practice were compared with visual estimates. RESULTS: In the silicone model, visual estimation had the largest median percentage error of 25.1 % (95 %CI 19.1 %-30.4 %), followed by biopsy forceps-based estimation: median 20.0 % (95 %CI 14.4 %-25.6 %). Poseidon gave a significantly lower median percentage error of 7.4 % (95 %CI 5.0 %-9.4 %) compared with other methods. During routine colonoscopies, Poseidon presented a significantly lower median percentage error (7.7 %, 95 %CI 6.1 %-9.3 %) than visual estimation (22.1 %, 95 %CI 15.1 %-26.9 %). CONCLUSION: In this work, we present a novel AI-based method for measuring colorectal polyp size with significantly higher accuracy than other common sizing methods.

Sustained virological response in the antiviral therapy of chronic hepatitis C: is there a predictive value of interferon-induced depression?

BACKGROUND: The study objective was to determine the contribution of cytokine-induced depression to a predictive model of sustained virological response (SVR) in chronic hepatitis C. METHODS: One hundred and one therapy-naïve hepatitis C virus (HCV) outpatients received treatment with peginterferon alfa-2b and ribavirin. Neuropsychiatric side effects were monitored prospectively (Hospital Anxiety and Depression Scale, DSM-IV criteria for major depression). SVR was defined as a failure to detect HCV by PCR 24 weeks after therapy. RESULTS: SVR rate was 72.3% (73 of 101 patients). Classification data and the extent of interferon-induced depression were not significantly linked to SVR. Virus genotype (p = 0.045) and gender (p = 0.016) contributed significantly to a logistic regression model. Mean (p = 0.811) and maximum (p = 0.744) depression increases were no significant predictors of SVR. Major depression rates (DSM-IV criteria) were 12.3% (9 of 73 patients) in the subgroup with SVR and 10.7% (3 of 28) in patients without SVR. CONCLUSIONS: We found no significant association between depression and the efficacy of antiviral treatment in chronic hepatitis C. Interferon-induced depressive symptoms are important to be monitored and treated if necessary; however, they cannot be used to predict therapy success.

Expression profiling and genetic alterations of the selenoproteins GI-GPx and SePP in colorectal carcinogenesis.

The trace element selenium is discussed as a chemopreventive agent in colorectal carcinogenesis. Selenocysteine-containing proteins, so-called selenoproteins, represent potential molecular targets for nutritive selenium supplementation. Due to their antioxidative potential, the selenoproteins gastrointestinal glutathione peroxidase (GI-GPx) and selenoprotein P (SePP) are considered to provide protection against reactive oxygen species (ROS), thereby reducing DNA damage and preventing development of colon cancer. GI-GPx and SePP are abundantly expressed in normal colon mucosa. Recently, we demonstrated both reduced SePP expression and increased GI-GPx expression in colorectal adenomas. In this study, we investigated the expression of SePP and GI-GPx in colorectal cancers compared with corresponding normal mucosa. Further, the occurrence of genetic alterations within the SePP and GI-GPx genes was analyzed. We observed a significant reduction or loss of SePP mRNA expression in colon cancers, whereas GI-GPx mRNA and protein expression varied between different tumor samples. In addition, we identified novel polymorphisms within the SePP and GI-GPx genes with so far unknown relevance for protein function. Our results argue against a general decrease of selenoprotein expression in colorectal carcinogenesis but imply specific differential regulation of expression of individual selenoproteins.

Glutathione peroxidase isoforms as part of the local antioxidative defense system in normal and Barrett's esophagus.

The development of an oesophageal adenocarcinoma arising in Barrett's mucosa is associated with a multistep process of genetic lesions that may be triggered by persistent oxidative damage. The glutathione peroxidase isoforms pGPx and GI-GPx, which were identified recently in the mucosa of the esophagus, may play a role as defense factors to prevent such oxidative injury. To determine alterations of the expression of pGPx and GI-GPx in Barrett's mucosa as compared to primary and regenerative squamous epithelium. Biopsy samples of oesophageal mucosa of patients with Barrett's esophagus (n = 12), patients with squamous restoration after thermal ablation (n = 10), and healthy controls (n = 5) were analyzed for pGPx and GI-GPx mRNA expression by Northern blot and for glutathione peroxidase activity by enzymatic assay. Squamous regeneration was induced by argon plasma coagulation (APC) combined with proton pump inhibitor therapy. In Barrett's epithelium mRNA levels of pGPx (the secreted isoform) were significantly reduced and of GI-GPx (the intracellular isoform) significantly increased as compared to normal squamous mucosa. In squamous mucosa that had regenerated after APC, no significant differences compared to the expression pattern of primary squamous mucosa were found. Compared to squamous mucosa, Barrett's metaplasia shows a different mRNA expression of pGPx and GI-GPx that may be associated with increased susceptibility to oxidative damage.