Age-Specific ADME Gene Expression in Infant Intestinal Enteroids.

In childhood, developmental changes and environmental interactions highly affect orally dosed drug disposition across the age range. To optimize dosing regimens and ensure safe use of drugs in pediatric patients, understanding this age-dependent biology is necessary. In this proof-of-concept study, we aimed to culture age-specific enteroids from infant tissue which represent its original donor material, specifically for drug transport and metabolism. Enteroid lines from fresh infant tissues (n = 8, age range: 0.3-45 postnatal weeks) and adult tissues (n = 3) were established and expanded to 3D self-organizing enteroids. The gene expression of drug transporters P-gp (ABCB1), BCRP (ABCG2), MRP2 (ABCC2), and PEPT1 (SLC15A1) and drug metabolizing enzymes CYP3A4, CYP2C18, and UGT1A1 was determined with RT-qPCR in fresh tissue and its derivative differentiated enteroids. Expression levels of P-gp, BCRP, MRP2, and CYP3A4 were similar between tissues and enteroids. PEPT1 and CYP2C18 expression was lower in enteroids compared to that in the tissue. The expression of UGT1A1 in the tissue was lower than that in enteroids. The gene expression did not change with the enteroid passage number for all genes studied. Similar maturational patterns in tissues and enteroids were visually observed for P-gp, PEPT1, MRP2, CYP3A4, CYP2C18, and VIL1. In this explorative study, interpatient variability was high, likely due to the diverse patient characteristics of the sampled population (e.g., disease, age, and treatment). To summarize, maturational patterns of clinically relevant ADME genes in tissue were maintained in enteroids. These findings are an important step toward the potential use of pediatric enteroids in pediatric drug development, which in the future may lead to improved pediatric safety predictions during drug development. We reason that such an approach can contribute to a potential age-specific platform to study and predict drug exposure and intestinal safety in pediatrics.

Feasibility and repeatability of ultrasound-guided surface electroenterography to measure colonic slow wave motility in healthy adults.

Surface electroenterography is a potential non-invasive alternative to current diagnostics of colonic motility disorders. However, electrode positioning in electroenterography is often based on general anatomy and may lack generalizability. Furthermore, the repeatability of electroenterography measurements is unknown. This study aimed to evaluate ultrasound-guided electrode positioning for electroenterography measurements and to determine the repeatability of those measurements. In ten healthy adults, two electroenterography procedures were performed, consisting of fasting, ultrasound-guided electrode localization and two 20-minute electroenterography recordings separated by a meal. The dominant frequency, the mean power density (magnitude of colonic motility) and the power percent difference (relative pre- to postprandial increase in magnitude) were determined. Repeatability was determined by Lin's concordance correlation coefficient. The results demonstrated that the dominant frequency did not differ between pre- and postprandial recordings and was 3 cpm, characteristic of colonic motility. The mean power density increased between the pre- and postprandial measurements, with an average difference of over 200%. The repeatability of both the dominant frequency and power density was poor to moderate, whereas the correlation coefficient of the power percent difference was poor. Concluding, ultrasound-guided surface electroenterography seems able to measure the gastrocolic reflex, but the dissatisfactory repeatability necessitates optimization of the measurement protocol.

Alcohol's impact on fine motor skills: Insights from minimally invasive surgical simulation.

Background: Alcohol misuse among medical professionals poses a significant concern, and there is a lack of clarity in (inter)national guidelines regarding alcohol use during work. Moreover, there exists an insufficient body of research on the specific impact of alcohol on fine motor skills within the medical sector, specifically surgery. This study aims to investigate the impact of alcohol on fine motor skills in a minimally invasive surgical setting. Methods: A cross-sectional study was conducted at Lowland Science on August 19th, 20th, and 21st, 2022, during the Lowlands music festival in Biddinghuizen, the Netherlands. Participants were divided into five groups based on measured alcohol consumption. Exclusion criteria included drug use, prior surgical experience, being underage, and previous participation. The main outcomes were the number of correctly transferred rings during the PEG transfer task and the number of errors. Blood alcohol concentration (BAC) was measured using a breathalyser. Results: A total of 1056 participants were included in the study. The results indicated an inverse relationship between BAC levels and surgical performance, with higher alcohol levels associated with a decrease in performance (p = 0.023). However, there was no significant difference in the number of errors among the five groups (p = 0.597). The group with the highest alcohol consumption (BAC >0.08 %) exhibited significantly worse performance compared to the group with a BAC of 0.0 % (p = 0.002). Conclusion: This study uncovers a negative impact of increased alcohol intake on fine motor skills in a minimally invasive surgery simulation exercise. While there was no effect on the occurrence of errors. Professional medical organizations should reconsider and explicate their position on alcohol use in (surgical) healthcare.

Self-assessment, and not continuous training, improves basic open suturing skills.

BACKGROUND: To develop and maintain suturing skills, clinical exposure is important. When clinical exposure cannot be guaranteed, an adequate training schedule for suturing skills is required. This study evaluates the effect of continuous training, 'reflection before practice' and self-assessment on basic open suturing skills. METHODS: Medical students performed four basic suturing tasks on a simulation set up before ('pre-test') and after their surgical rotation ('after-test'). Participants were divided in three groups; the 'clinical exposure group' (n = 44) had clinical exposure during their rotation only, the 'continuous training group' (n = 16) completed a suturing interval training during their rotation and the 'self-assessment group' (n = 16) also completed a suturing interval training, but with the use of reflection before practice and self-assessment. Parameters measured by a tracking system during the suturing tasks and a calculated 'composite score' were compared between groups and test-moments. RESULTS: A significantly better composite score was found at the after-test compared to the pre-test for all groups for all basic suturing tasks (0.001 ≤ p ≤ 0.049). The self-assessment group scored better at the pre-test than the other two groups for all tasks, except for 'knot tying by hand' (0.004 ≤ p ≤ 0.063). However, this group did not score better at the after-test for all tasks, compared to the other two groups. This resulted in a smaller delta of time ('transcutaneous suture', p = 0.013), distance ('Donati suture' and 'intracutaneous suture', 0.005 ≤ p ≤ 0.009) or composite score (all tasks, except for knot tying by hand, 0.007 ≤ p ≤ 0.061) in the self-assessment group. CONCLUSION: Reflection before practice and self-assessment during continuous training of basic open suturing tasks, may improve surgical skills at the start of the learning curve.

Comparing surface electroenterography measurements between patients suffering from Hirschsprung's disease and controls: a feasibility study.

Current diagnostics in Hirschsprung's disease are often challenging and invasive. This study aims to investigate whether surface electroenterography can non-invasively discern healthy subjects from subjects suffering from Hirschsprung's disease. Nine healthy subjects (seven children, two adults) and eleven subjects suffering from surgically untreated Hirschsprung's disease (nine children, two adults) underwent an electroenterography procedure. This procedure consisted of ultrasound-guided placement of surface electrodes on the abdomen covering all parts of the colon, fasting and two 20-min electroenterography measurements separated by a meal. The dominant frequency, magnitude and relative increase (pre- to postprandial) of colonic activity were compared between both groups. The results showed that in the pediatric group, no significant differences in dominant frequency, colonic activity and relative power increase were observed between controls and patients. The adult patients showed decreased colonic motility and relative power increase in the electrodes closest to the distal colon, both when compared to the same electrodes in controls and to the more proximal electrodes of themselves. To conclude, electroenterography measurements in young children is challenging, but the results in adults demonstrate that these measurements can possibly distinguish between controls and Hirschsprung's patients. Therefore, optimization of electroenterography measurements in young children is necessary.

Concurrent validity of objective assessment by finger tracking for open surgical suturing training.

BACKGROUND: The aim of this study is to evaluate whether the parameters 'time' and 'distance', measured by SurgTrac, correlate with the assessment of the same skills by blinded experts. METHODS: Basic open suturing tasks were executed by medical students. SurgTrac software measured objective parameters by tracking fingers. The executed tasks were recorded by a tablet and additionally assessed by a blinded expert with a Competency Assessment Tool-form (CAT-form). A Pearson's correlation was used to investigate the correlation between the parameters and the outcomes of the expert assessment. RESULTS: A strong correlation between the measured parameters of SurgTrac and the expert-assessment was found for knot tying by hand (r â€‹= â€‹-0.703) and vertical mattress suture (r â€‹= â€‹-0.644) and a moderate correlation for transcutaneous suture (r â€‹= â€‹-0.555) and intracutaneous suture (r â€‹= â€‹-0.451). CONCLUSION: The use of finger tracking by SurgTrac showed a good concurrent validity for the basic open suturing tasks knot tying by hand, transcutaneous suture and vertical mattress suture.

The potential of enteroids derived from children and adults to study age-dependent differences in intestinal CYP3A4/5 metabolism.

Drug metabolism in the intestinal wall affects bioavailability of orally administered drugs and is influenced by age. Hence, it is important to fully understand the drug metabolizing capacity of the gut to predict systemic exposure. The aim of this study was to investigate the potential of enteroids as a tool to study CYP3A4/5 -mediated metabolism in both children and adults. Bioconversion of midazolam, a CYP3A4/5 model substrate, was studied using enteroid monolayers as well as tissue explants in the Ussing chamber, both derived from pediatric [median (range age): 54 weeks (2 days - 13 years), n = 21] and adult (n = 5) tissue. Caco-2 cellular monolayers were employed as controls. In addition, mRNA expression of CYP3A4 was determined in enteroid monolayers (n = 11), tissue (n = 23) and Caco-2 using RT-qPCR. Midazolam metabolism was successfully detected in all enteroid monolayers, as well as in all tissue explants studied in the Ussing chamber, whereas Caco-2 showed no significant metabolite formation. The extracted fraction of midazolam was similar between enteroid monolayers and tissue. The fraction of midazolam extracted increased with age in enteroid monolayers derived from 0 to 70 week old donors. No statistically significant correlation was observed in tissue likely due to high variability observed and the smaller donor numbers included in the study. At the level of gene expression, CYP3A4 increased with age in tissues (n = 32), while this was not reflected in enteroid monolayers (n = 16). Notably, asymmetric metabolite formation was observed in enteroids and tissue, with higher metabolite formation on the luminal side of the barrier. In summary, we demonstrated that enteroids can be used to measure CYP3A4/5 midazolam metabolism, which we show is similar as observed in fresh isolated tissue. This was the case both in children and adults, indicating the potential of enteroids to predict intestinal metabolism. This study provides promising data to further develop enteroids to study drug metabolism in vitro and potentially predict oral absorption for special populations as an alternative to using fresh tissue.