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This article discusses the development of an artificial intelligence model to identify duodenal polyps in patients with Familial Adenomatous Polyposis (FAP). The researchers used a database of FAP patients who underwent upper GI tract endoscopic surveillance to obtain high-quality images of duodenal polyps. They then employed a deep learning-based biomedical image segmentation method to automate the segmentation of the polyps. The model achieved a mean polyp detection rate of over 80% with a relatively low rate of false positives. However, further refinement is needed for situations with a higher polyp burden. [Extracted from the article]

Redundant colon, also referred to as "dolichocolon," is an anatomical variant associated with elongation and redundancy thought to be associated with constipation, abdominal pain, and distention. 1,2 Diagnosis requires radiological visualization of the non-dilated colon in situ via barium enema or abdominopelvic computed tomography (CT). Colonic redundancy is based on 3 criteria: sigmoid loop displaced cranially relative to the iliac crests (type 1); transverse colon caudal to the iliac crests (type 2); and redundant loops at the hepatic or splenic flexure (type 3). 2 Rarely, dolichocolon may meet all 3 criteria. 2 ., (Copyright © 2024 AGA Institute. Published by Elsevier Inc. All rights reserved.)

Treelines advance due to climate warming. The impacts of this vegetation shift on plant-soil nutrient cycling are still uncertain, yet highly relevant as nutrient availability stimulates tree growth. Here, we investigated nitrogen (N) and phosphorus (P) in plant and soil pools along two tundra-forest transects on Kola Peninsula, Russia, with a documented elevation shift of birch-dominated treeline by 70 m during the last 50 years. Results show that although total N and P stocks in the soil-plant system did not change with elevation, their distribution was significantly altered. With the transition from high-elevation tundra to low-elevation forest, P stocks in stones decreased, possibly reflecting enhanced weathering. In contrast, N and P stocks in plant biomass approximately tripled and available P and N in the soil increased fivefold toward the forest. This was paralleled by decreasing carbon (C)-to-nutrient ratios in foliage and litter, smaller C:N:P ratios in microbial biomass, and lower enzymatic activities related to N and P acquisition in forest soils. An incubation experiment further demonstrated manifold higher N and P net mineralization rates in litter and soil in forest compared to tundra, likely due to smaller C:N:P ratios in decomposing organic matter. Overall, our results show that forest expansion increases the mobilization of available nutrients through enhanced weathering and positive plant-soil feedback, with nutrient-rich forest litter releasing greater amounts of N and P upon decomposition. While the low N and P availability in tundra may retard treeline advances, its improvement toward the forest likely promotes tree growth and forest development., (© 2024 The Authors. Global Change Biology published by John Wiley & Sons Ltd.)

Background: In constipated individuals, high-resolution anorectal manometry (HRM) may suggest the presence of a defecatory disorder. Despite known physiological differences between men and women, our understanding of functional anorectal pathophysiology is based upon predominantly female cohorts. Results are generalized to men., Aims: To evaluate whether recto-anal pressure patterns in constipated men are similar to those in constipated women., Methods: The electronic health records at Mayo Clinic, Rochester were used to identify constipated adult patients, without organic anorectal disease, who had undergone HRM and balloon expulsion testing (BET) in 2018, 2019, and 2020. Comparative analyses were performed., Results: Among 3,298 constipated adult patients (2,633 women, 665 men), anal and rectal pressures were higher in men. Women more likely to have HRM findings suggestive of a defecatory disorder (39% versus 20%, P < 0.001). Women were more likely to exhibit a type 4 pattern (27% versus 14%, P < 0.001), and less likely to exhibit a type 1 pattern (14% versus 38%, P < 0.001), of dyssynergia. Men were more likely to have an abnormal balloon expulsion test (BET, 34% versus 29%, P = 0.006). Nominal logistic regression demonstrates that male sex, age over 50 years, reduced recto-anal gradient during simulated evacuation, and types 2 and 4 dyssynergia are associated with an abnormal BET., Conclusions: In this large retrospective study, constipated men and women exhibited different patterns of dyssynergia both in the presence and absence of an abnormal BET. These findings were independent of sex-specific baseline physiological differences., (© 2022. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Purpose: For patients affected by autosomal-dominant polycystic kidney disease (ADPKD), successful differentiation of cysts is useful for automatic classification of patient phenotypes, clinical decision-making, and disease progression. The objective was to develop and evaluate a fully automated semantic segmentation method to differentiate and analyze renal cysts in patients with ADPKD., Methods: An automated deep learning approach using a convolutional neural network was trained, validated, and tested on a set of 60 MR T2-weighted images. A three-fold cross-validation approach was used to train three models on distinct training and validation sets (n = 40). An ensemble model was then built and tested on the hold out cases (n = 20), with each of the cases compared to manual segmentations performed by two readers. Segmentation agreement between readers and the automated method was assessed., Results: The automated approach was found to perform at the level of interobserver variability. The automated approach had a Dice coefficient (mean ± standard deviation) of 0.86 ± 0.10 vs Reader-1 and 0.84 ± 0.11 vs. Reader-2. Interobserver Dice was 0.86 ± 0.08. In terms of total cyst volume (TCV), the automated approach had a percent difference of 3.9 ± 19.1% vs Reader-1 and 8.0 ± 24.1% vs Reader-2, whereas interobserver variability was - 2.0 ± 16.4%., Conclusion: This study developed and validated a fully automated approach for performing semantic segmentation of kidney cysts in MR images of patients affected by ADPKD. This approach will be useful for exploring additional imaging biomarkers of ADPKD and automatically classifying phenotypes.

A previously undescribed badnavirus was isolated from Zamia fischeri showing symptoms of chlorosis, necrosis, and ringspot. The virus has bacilliform virions 30 nm in diameter and averaging 120 nm in length. The viral genome is 9227 bp in length and contains three open reading frames characteristic of members of the genus Badnavirus. The largest open reading frame (ORF3) encodes a putative polyprotein, with predicted domains including zinc finger, aspartic protease, reverse transcriptase (RT) and RNase H. The virus is tentatively named "cycad leaf necrosis virus" (CLNV). Within the genus Badnavirus, CLNV was most closely related to sugarcane bacilliform Guadeloupe D virus (FJ439817), sharing 69% identity at the nucleotide level in the RT + RNase H region. This virus is the first badnavirus reported to infect cycads, and it has the largest genome among the currently characterized badnaviruses.

Clogging of streambeds by suspended particles (SP) can cause environmental problems, as it can negatively influence, e.g., habitats for macrozoobenthos, fish reproduction and groundwater recharge. This especially applies in the case of silt-sized SP. Until now, most research has dealt with coarse SP and was carried out in laboratory systems. The aims of this study are to examine (1) whether physical clogging by silt-sized SP exhibits the same dynamics and patterns as by sand-sized SP, and (2) the comparability of results between laboratory and field experiments. We carried out vertical column experiments with sand-sized bed material and silt-sized SP, which are rich in mica minerals. In laboratory experiments, we investigated the degree of clogging quantified by the reduction of porosity and hydraulic conductivity and the maximum clogging depth as a function of size and shape of bed material, size of SP, pore water flow velocity, and concentration of calcium cations. The SP were collected from an Alpine sedimentation basin, where our field experiments were carried out. To investigate the clogging process in the field, we buried columns filled with sand-sized quartz in the stream bed. We found that the maximal bed-to-grain ratio where clogging still occurs is larger for silt-sized SP than for sand-sized SP. The observed clogging depths and the reduction of flow rate through the column from our laboratory experiments were comparable to those from the field. However, our field results showed that the extent of clogging strongly depends on the naturally-occurring hydrological dynamics. The field location was characterized by a more polydisperse suspension, a strongly fluctuating water regime, and high SP concentrations at times, leading to more heterogeneous and more pronounced clogging when compared to laboratory results., (Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.)