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Groen, Piet C. de

https://orcid.org/0000-0002-2560-1254

Mayo Clinic

University of Minnesota

Citations 13

A survey of colonoscopists with and without in‐depth knowledge of water‐aided colonoscopy
Leung, Felix W. , Koo, Malcolm , Yen, Andrew W. , Siau, Keith , Hsieh, Yu‐Hsi , Ishaq, Sauid , Cheng, Chi‐Liang , Ramirez, Francisco C. , Bak, Adrian, Karnes, William E. , Bayupurnama, Putut , Leung, Joseph W., Groen, Piet C. de , Hsieh, Yu-Hsi , Ishaq, Sauid , Cheng, Chi-Liang , Bayupurnama, Putut , Cadoni, Sergio

Journal of Gastroenterology and Hepatology | May 26, 2022 | Volume: 37 | Issue: 9 | Pages: 1785-1791

10.1111/jgh.15896 Get It

AbstractBackground and AimEndoscopy 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.MethodsA questionnaire was sent by email to the MDCR authors with an in‐depth knowledge of WAC. They responded and also invited colleagues and trainees without in‐depth knowledge to respond. Logistic regression analysis was used with the reasons for WAC use treated as the primary outcome. Reports related to WAC post MDCR were identified.ResultsOf 100 respondents, > 80% indicated willingness to adopt and modify practice to accommodate WAC. Higher adenoma detection rate (ADR) incentivized WE use. Procedure time slots ≤ 30 and > 30 min significantly predicted WI and WE use, respectively. Co‐authors of the MDCR were significantly more likely to perform WAC (odds ratio [OR] = 7.5, P = 0.037). Unfamiliarity with (OR = 0.11, P = 0.02) and absence of good experience (OR = 0.019, P = 0.002) were associated with colonoscopists less likely to perform WAC. Reports related to WAC post MDCR revealed overall and right colon WE outcomes continued to improve. Network meta‐analyses showed that WE was superior to Cap and Endocuff. On‐demand sedation with WE shortened nursing recovery time.ConclusionsAn important predictor of WAC use was experience. Superior outcomes continued to be reported with WE.
Temporal Annotation in the Clinical Domain
Styler, William F., Finan, Sean , Pradhan, Sameer , Groen, Piet C. de , Erickson, Brad, Lin, Chen, Savova, Guergana , Pustejovsky, James , Bethard, Steven J. , Palmer, Martha , Miller, Timothy A.

Transactions of the Association for Computational Linguistics | December 28, 2018 | Volume: 2 | Issue: No issue available | Pages: 143-154

10.1162/tacl_a_00172 Get It

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)”. To clarify what relations merit annotation, we distinguish between linguistically-derived and inferentially-derived temporal orderings in the text. We also apply a top performing TempEval 2013 system against this new resource to measure the difficulty of adapting systems to the clinical domain. The corpus is available to the community and has been proposed for use in a SemEval 2015 task.
Kinetic and molecular identification of sodium-dependent glucose transporter in normal rat cholangiocytes
Pham, Linh , Vroman, Benjamin T., Groen, Piet C. de , LaRusso, N. F., Lazaridis, Konstantinos N.

American Journal of Physiology-Gastrointestinal and Liver Physiology | December 24, 2017 | Volume: 272 | Issue: 5 | Pages: G1168-G1174

10.1152/ajpgi.1997.272.5.g1168 Get It

While previous work has demonstrated that monosaccharides can be absorbed from bile, studies of sugar transport by the biliary, epithelia (i.e., cholangiocytes) are lacking. Using a novel model of polarized rat cholangiocytes in primary culture, designated normal rat cholangiocytes (NRC), we examined directly the uptake and transcellular transport of a nonmetabolizable monosaccharide, methyl alpha-D-glucopyranoside (AMG). When the apical or basolateral domain of cholangiocytes was exposed to radiolabeled AMG or sucrose (control), only apical absorption of AMG was evident. This apical uptake was time dependent, saturable, and significantly inhibited (> or = 90%) by removal of Na+ or in the presence of phlorizin (0.1 mM), a competitive inhibitor of the Na(+)-glucose cotransporter. The transcellular flux of AMG was also polar (i.e., apical to basolateral). Reverse transcriptase-polymerase chain reaction (RT-PCR) revealed the presence of the transcript for the specific Na(+)-glucose cotransporter SGLT1 in NRC and in freshly isolated cholangiocytes but not in purified hepatocytes; in contrast, the transcript for SGLT2 was absent in all liver samples. In situ RT-PCR on frozen sections of normal rat liver showed that SGLT1 was expressed exclusively in cholangiocytes. Immunoblot analysis using a specific polyclonal antibody for the facilitative glucose transporter GLUT1 demonstrated it to be present in vesicles derived from NRC enriched in basolateral plasma membrane domains. Our data are consistent with the concept that SGLT1 is present on the apical domain of biliary epithelia and, in conjunction with GLUT1 on the basolateral domain, accounts for glucose absorption from bile.
Purification and immunological quantification of rat liver lysosomal glycosidases
Groen, Piet C. de , LeSage, Gene, Tietz, P., LaRusso, Nicholas F.

Biochemical Journal | August 10, 2015 | Volume: 264 | Issue: 1 | Pages: 115-123

10.1042/bj2640115 Get It

Although lysosomal enzyme activities are known to vary in response to numerous physiological and pharmacological stimuli, the relationship between lysosomal enzyme activity and enzyme concentration has not been systematically studied. Therefore we developed radioimmunoassays for two lysosomal glycosidases in order to determine lysosomal enzyme concentration. beta-Galactosidase and beta-glucuronidase were purified from rat liver 2780-fold and 1280-fold respectively, by using differential centrifugation, affinity chromatography, ion-exchange chromatography and molecular-sieve chromatography. Polyclonal antibodies to these enzymes were raised in rabbits, and two radioimmunoassays were established. Antibody specificity was shown by: (i) selective immunoprecipitation of enzyme activity; (ii) identical bands of purified enzyme on SDS/polyacrylamide-gel electrophoresis and immunoelectrophoresis; (iii) single immunoreactive peaks in molecular-sieve chromatography experiments. Sensitivities of the assays were such that 15 ng of beta-galactosidase and 45 ng of beta-glucuronidase decreased the ratio of bound to free radiolabel by 50%; minimal detectable amounts of immunoreactive enzymes were 2 ng and 10 ng respectively. The assays were initially used to assess the effects of physiological perturbations (i.e. fasting and age) on enzyme concentrations in rat liver; these experiments showed that changes in enzyme concentrations do not always correlate with changes in enzyme activities. This represents the first report of radioimmunoassays for lysosomal glycosidases. The results suggest that these radioimmunoassays provide useful technology for the study of regulatory control mechanisms of the concentrations of lysosomal glycosidases in mammalian tissues.
Authors' response to Eluri et al. letter to the editor regarding: Colorectal cancer prevention by an optimized colonoscopy protocol in routine practice
Xirasagar, Sudha , Groen, Piet C. de , de Groen, Piet C

International Journal of Cancer | February 7, 2015 | Volume: 137 | Issue: 5 | Pages: 1247-1248

10.1002/ijc.29472 Get It

Colorectal cancer prevention by an optimized colonoscopy protocol in routine practice
Xirasagar, Sudha , Li, Yi‐Jhen, Hurley, Thomas G. , Tsai, Meng‐Han , Hardin, James W. , Hurley, Deborah , Groen, Piet C. de , Hébert, James R.

International Journal of Cancer | September 20, 2014 | Volume: 136 | Issue: 6 | Pages: No page available

10.1002/ijc.29228 Get It

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. Data on 16,315 patients were merged with the South Carolina Central Cancer Registry and Vital Records Registry data from January 1996 to December 2009 to identify incident CRC cases and deaths, incident lung cancers and brain cancer deaths (comparison control cancers). The standardized incidence ratios (SIR) and standardized mortality ratios (SMR) relative to South Carolina and US SEER‐18 population rates were calculated. Over 78,375 person‐years of observation, 18 patients developed CRC versus 104.11 expected for an SIR of 0.17, or 83% CRC protection, the rates being 68% and 91%, respectively among the adenoma‐ and adenoma‐free subgroups (all p < 0.001). Restricting the cohort to ensure minimum 5‐year follow‐up (mean follow‐up 6.64 years) did not change the results. The CRC mortality reduction was 89% ( p < 0.001; four CRC deaths vs . 35.95 expected). The lung cancer SIR was 0.96 ( p = 0.67), and brain cancer SMR was 0.92 ( p = 0.35). Over 80% reduction in CRC incidence and mortality is achievable in routine practice by implementing key colonoscopy principles targeting near‐complete polyp clearance.
Discontinuation of Statins in Routine Care Settings
Groen, Piet C. de

Annals of Internal Medicine | July 1, 2013 | Volume: 159 | Issue: 1 | Pages: 74

10.7326/0003-4819-159-1-201307020-00020 Get It

The Ethics of Using Web Technology To Find Research Participants
Groen, Piet C. de

Annals of Internal Medicine | April 12, 2013 | Volume: 130 | Issue: 3 | Pages: 245-246

10.7326/0003-4819-130-3-199902020-00038 Get It

Computer-aided detection of retroflexion in colonoscopy
Wang, Yi , Tavanapong, Wallapak , Wong, Johnny, Oh, JungHwan , Groen, Piet C. de

2011 24th International Symposium on Computer-Based Medical Systems (CBMS) | August 31, 2011 | Volume: No volume available | Issue: No issue available | Pages: 1-6

10.1109/cbms.2011.5999137 Get It

Stool detection in colonoscopy videos
Hwang, Sae, Tavanapong, Wallapak , Wong, Johnny, Groen, Piet C. de , Oh, Junghwan

2008 30th Annual International Conference of the IEEE Engineering in Medicine and Biology Society | February 2, 2009 | Volume: No volume available | Issue: No issue available | Pages: 3004-3007

10.1109/iembs.2008.4649835 Get It