Christopher P. Walker

Aims Therapeutic interventions during device-assisted enteroscopy (DAE) are technically demanding due to a number of factors including, length of scope, stability in the small bowel, and thin diameter of the small bowel wall. Our aim was to retrospectively assess complication rates in device-assisted enteroscopy in our center. Methods A retrospective review was performed of consecutive DAE procedures performed over a period of 24 months to July 2022. Data including procedure indication, patient demographics as well as procedural details including interventions and complications were recorded. Results 292 procedures were identified over the period of analysis. Of these 228 (78%) were double balloon vs 64 (22%) single balloon. The mean age of patients was 61.6 years with a slight male predominance of 54.9%. 124 (43%) procedures involved a therapeutic intervention. Of these, 106 (85%) involved the treatment of vascular lesions, 95 used argon plasma coagulation (APC) alone, a further 8 used a combination of APC and endoscopic clips and clips alone in 3 cases. 11 (4%) cases involved polypectomy, while 7 (6%) involved cases of stricture dilatation (including 2 capsule retrievals). Complications were rare, with only 3(1%) recorded. One patient was admitted with post-procedural hypotension and metabolic acidosis. 2 others were admitted for monitoring post-treatment of bleeding lesions, neither required reintervention. Conclusions DAE includes a high rate of therapeutic intervention. Given this it is a safe procedure with a few complications. Article published online: 14 April 2023 © 2023. European Society of Gastrointestinal Endoscopy. All rights reserved. Georg Thieme Verlag KG Rüdigerstraße 14, 70469 Stuttgart, Germany

With the emergence of glycated hemoglobin as a diagnostic test for diabetes, oral glucose tolerance tests (OGTTs) have become rare in endocrinology practice. As they have moved out of favor, the importance of patient instructions on preparation prior to OGTT has faded from memory. Decades-old literature, well-known to endocrinologists a generation ago, emphasized the importance of carbohydrate intake prior to OGTT. In this expert endocrine consult, we discuss an OGTT performed in a research setting without adequate carbohydrate intake at the evening meal prior to the OGTT. The resultant elevated plasma glucose levels at 1-hour and 2-hours mimicked the loss of first-phase insulin release seen in early type 1 and type 2 diabetes. With clinical concern that the research participant had evolving type 1 or type 2 diabetes, the volunteer was subjected to additional testing and experienced anxiety. Repeat OGTT was normal after adequate carbohydrate intake (>150 grams/day and >50 grams the evening prior to overnight fast for the study). The physiology of this phenomenon is explored and is likely mediated through beta cell adaptation and alteration in peripheral glucose uptake in response to nutrient exposure. The learnings of decades ago have clearly faded, and this literature should be revisited to ensure that OGTT results are not compromised when ordered for clinical or research purposes.

New Findings What is the central question of this study? Glucose is the dominant energy source for the brain. However, little is known about how glucose metabolism impacts the coordination of network activity in the brain in healthy adults. What is the main finding and its importance? We demonstrate that both alpha oscillations and the aperiodic signal components of resting electroencephalography are both modulated by experimentally elevated blood glucose levels. Our findings suggest that glucose increases measures associated with excitation‐inhibition (E:I) balance, but that the effect on alpha oscillations may plateau at a certain level. Understanding the relationship between glucose consumption and E:I balance is critical to developing our understanding of how metabolism shapes human brain activity. Abstract Brain network oscillations can broadly be divided into periodic and aperiodic signal components which are sensitive to state‐dependent changes in network coordination and excitation to inhibition (E:I) balance. We sought to address whether the brain's dominant energy source, glucose, is implicated in regulating network activity and excitability. We conducted an experimenter‐blind, crossover study of the effect of blood glucose level (BGL) on the resting electroencephalography (EEG) frequency spectrum. Participants consumed a glucose drink (75 g glucose) or an equivalent volume of water on two separate visits. EEG data were sampled before and up to three hours after the drink. We found the experimentally induced changes in BGL exhibited an inverted u‐shaped relationship with changes in the individual alpha frequency peak, whereas the slope of the aperiodic signal component of the frequency spectrum showed a positive linear association suggestive of greater excitation. By contrast, peak alpha power—typically associated with top‐down inhibitory processes—was negatively associated with changes in BGL. Collectively these results suggest that high BGL alters brain network coordination in the form of alpha oscillations and measures associated with E:I balance. This article is protected by copyright. All rights reserved

Dysregulation of the inositol cycle is implicated in a wide variety of human diseases, including developmental defects and neurological diseases. A homozygous frameshift mutation in IMPA1, coding for the enzyme inositol monophosphatase 1 (IMPase), has recently been associated with severe intellectual disability (ID) in a geographically isolated consanguineous family in Northeastern Brazil (Figueredo et al., 2016). However, the neurophysiologic mechanisms that mediate the IMPA1 mutation and associated ID phenotype have not been characterized. To this end, resting EEG (eyes-open and eyes-closed) was collected from the Figueredo et al. pedigree. Quantitative EEG measures, including mean power, dominant frequency and dominant frequency variability, were investigated for allelic associations using multivariate family-based association test using generalized estimating equations. We found that the IMPA1 mutation was associated with relative decreases in frontal theta band power as well as altered alpha-band variability with no regional specificity during the eyes-open condition. For the eyes-closed condition, there was altered dominant theta frequency variability in the central and parietal regions. These findings represent the first human in vivo phenotypic assessment of brain function disturbances associated with a loss-of-function IMPA1 mutation, and thus an important first step towards an understanding the pathophysiologic mechanisms of intellectual disability associated with the mutation that affects this critical metabolic pathway.