Publications by authors named "Piet C de Groen"

The aetiology of type 1 diabetes (T1D) is considered multifactorial with the contribution of the MHC on chromosome 6 being most important. Multiple factors also contribute to the aetiology of colorectal neoplasia, but the final event causing the change from normal mucosa to polyp and from polyp to cancer is due to a single somatic mutation event. Repeated formation of colorectal neoplasia within an at-risk population results in a predictable, tapering, exponential neoplasia distribution.

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Muons, mutations, and planetary shielding.

Front Astron Space Sci

November 2022

Life on earth is protected from astrophysical cosmic rays by the heliospheric magnetic and slowly varying geomagnetic fields, and by collisions with oxygen and nitrogen molecules in the atmosphere. The collisions generate showers of particles of lesser energy; only muons, a charged particle with a mass between that of an electron and a proton, can reach earth's surface in substantial quantities. Muons are easily detected, used to image interior spaces of pyramids, and known to limit the stability of qubits in quantum computing; yet, despite their charge, average energy of 4 GeV and ionizing properties, muons are not considered to affect chemical reactions or biology.

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Background And Aim: Endoscopy featured water-aided colonoscopy (WAC) as novel in the Innovation Forum in 2011. Gastrointestinal Endoscopy published a modified Delphi consensus review (MDCR) that supports WAC for clinical practice in 2021. We tested the hypothesis that experience was an important predictor of WAC use, either as water immersion (WI), water exchange (WE), or a combination of WI and WE.

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During the past decades, many automated image analysis methods have been developed for colonoscopy. Real-time implementation of the most promising methods during colonoscopy has been tested in clinical trials, including several recent multi-center studies. All trials have shown results that may contribute to prevention of colorectal cancer.

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Background And Aims: Colorectal cancer (CRC) prevention by colonoscopy has been lower than expected. We studied CRC prevention outcomes of a colonoscopy protocol based on Clean the colon, Look Everywhere, and complete Abnormality Removal (CLEAR) principles.

Methods: This observational follow-up study studied patients provided screening colonoscopy at a free-standing private ambulatory surgery center in South Carolina by 80 endoscopists from October 2001 to December 2014, followed through December 2015.

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With 23 and 47% higher colorectal cancer (CRC) incidence and mortality, respectively, among African Americans vs. Whites, CRC screening studies are important. Screening guidelines recommend 5-yearly colonoscopy screening of persons with a family history of CRC (first-degree relatives, FDRs), beginning at 40 years of age.

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A workshop on ''Simulation Research in Gastrointestinal and Urologic Care: Challenges and Opportunities'' was held at the National Institutes of Health in June 2016. The purpose of the workshop was to examine the extent to which simulation approaches have been used by skilled proceduralists (not trainees) caring for patients with gastrointestinal and urologic diseases. The current status of research findings in the use and effectiveness of simulation applications was reviewed, and numerous knowledge gaps and research needs were identified by the faculty and the attendees.

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: A workshop on "Simulation Research in Gastrointestinal and Urologic Care: Challenges and Opportunities" was held at the National Institutes of Health in June 2016. The purpose of the workshop was to examine the extent to which simulation approaches have been used by skilled proceduralists (not trainees) caring for patients with gastrointestinal and urologic diseases. The current status of research findings in the use and effectiveness of simulation applications was reviewed, and numerous knowledge gaps and research needs were identified by the faculty and the attendees.

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Water exchange (WE) is a relatively new method of endoscope insertion during colonoscopy. Although its origin is rooted in the insertion phase of colonoscopy, allowing the procedure to proceed with more ease, less discomfort, and less or no sedation, its most important value may reside in the withdrawal phase. In this issue, a randomized, prospective study from China specifically designed to examine the effect of WE on adenoma detection rate (ADR) confirms previous findings: WE improves ADR.

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Introduction: Colonoscopy screening reduces colorectal cancer (CRC) incidence and mortality. CRC screening is recommended at age 50 for average-risk people. Screening of first-degree relatives of CRC patients is recommended to begin at age 40 or 10 years before the age at diagnosis of the youngest relative diagnosed with CRC.

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We present a software system called "Polyp-Alert" to assist the endoscopist find polyps by providing visual feedback during colonoscopy. Polyp-Alert employs our previous edge-cross-section visual features and a rule-based classifier to detect a polyp edge-an edge along the contour of a polyp. The technique employs tracking of detected polyp edge(s) to group a sequence of images covering the same polyp(s) as one polyp shot.

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We conducted a retrospective cohort study to investigate the colorectal cancer (CRC) incidence and mortality prevention achievable in clinical practice with an optimized colonoscopy protocol targeting near-complete polyp clearance. The protocol consisted of: (i) telephonic reinforcement of bowel preparation instructions; (ii) active inspection for polyps throughout insertion and circumferential withdrawal; and (iii) timely updating of the protocol and documentation to incorporate the latest guidelines. Of 17,312 patients provided screening colonoscopies by 59 endoscopists in South Carolina, USA from September 2001 through December 2008, 997 were excluded using accepted exclusion criteria.

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Finding mucosal abnormalities (e.g., erythema, blood, ulcer, erosion, and polyp) is one of the most essential tasks during endoscopy video review.

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This article discusses the requirements of a formal specification for the annotation of temporal information in clinical narratives. We discuss the implementation and extension of ISO-TimeML for annotating a corpus of clinical notes, known as the THYME corpus. To reflect the information task and the heavily inference-based reasoning demands in the domain, a new annotation guideline has been developed, "the THYME Guidelines to ISO-TimeML (THYME-TimeML)".

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This paper presents the first fully automated reconstruction technique of 3D virtual colon segments from individual colonoscopy images. It is the basis of new software applications that may offer great benefits for improving quality of care for colonoscopy patients. For example, a 3D map of the areas inspected and uninspected during colonoscopy can be shown on request of the endoscopist during the procedure.

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This paper presents a novel technique for automated detection of protruding polyps in colonoscopy images using edge cross-section profiles (ECSP). We propose a part-based multiderivative ECSP that computes derivative functions of an edge cross-section profile and segments each of these profiles into parts. Therefore, we can model or extract features suitable for each part.

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This paper describes the design and implementation of SAPPHIRE--a novel middleware and software development kit for stream programing on a heterogeneous system of multi-core multi-CPUs with optional hardware accelerators such as graphics processing unit (GPU). A stream program consists of a set of tasks where the same tasks are repeated over multiple iterations of data (e.g.

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Purpose: Intermediate-stage hepatocellular carcinoma (HCC) is usually treated with locoregional therapy using transarterial chemoembolization (TACE). Transarterial radioembolization (TARE) using β-emitting yttrium-90 integral to the glass matrix of the microspheres is an alternative to TACE. This retrospective case-control study compared the outcomes and safety of TARE versus TACE in patients with unresectable HCC.

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Background & Aims: Endoscopic healing is likely to become an important goal for treatment of patients with ulcerative colitis (UC). A simple validated endoscopic index is needed. We validated the previously developed UC Colonoscopic Index of Severity (UCCIS).

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