Gastrointestinal devices: common and uncommon foreign bodies.

Devices for the gastrointestinal tract are widely available and constantly advancing with less invasive techniques. They play a crucial role in diagnostic and therapeutic interventions and are commonly placed by interventional radiologists, gastroenterologists, and surgeons. These devices frequently appear in imaging studies, which verify their proper placement, identify any complications, or may be incidentally detected. Radiologists must be able to identify these devices at imaging and understand their intended purpose to assess their efficacy, detect complications such as incorrect positioning, and avoid misinterpreting them as abnormalities. Furthermore, many patients with these devices may require MRI, making assessing compatibility essential for safe patient care. This review seeks to provide a succinct and practical handbook for radiologists regarding both common and uncommon gastrointestinal devices. In addition to textual descriptions of clinical indications, imaging findings, complications, and MRI compatibility, the review incorporates a summary table as a quick reference point for key information and illustrative images for each device.

CT analysis of aortic calcifications to predict abdominal aortic aneurysm rupture.

BACKGROUND: Abdominal aortic aneurysm (AAA) rupture prediction based on sex and diameter could be improved. The goal was to assess whether aortic calcification distribution could better predict AAA rupture through machine learning and LASSO regression. METHODOLOGY: In this retrospective study, 80 patients treated for a ruptured AAA between January 2001 and August 2018 were matched with 80 non-ruptured patients based on maximal AAA diameter, age, and sex. Calcification volume and dispersion, morphologic, and clinical variables were compared between both groups using a univariable analysis with p = 0.05 and multivariable analysis through machine learning and LASSO regression. We used AUC for machine learning and odds ratios for regression to measure performance. RESULTS: Mean age of patients was 74.0 ± 8.4 years and 89% were men. AAA diameters were equivalent in both groups (80.9 ± 17.5 vs 79.0 ± 17.3 mm, p = 0.505). Ruptured aneurysms contained a smaller number of calcification aggregates (18.0 ± 17.9 vs 25.6 ± 18.9, p = 0.010) and were less likely to have a proximal neck (45.0% vs 76.3%, p < 0.001). In the machine learning analysis, 5 variables were associated to AAA rupture: proximal neck, antiplatelet use, calcification number, Euclidian distance between calcifications, and standard deviation of the Euclidian distance. A follow-up LASSO regression was concomitant with the findings of the machine learning analysis regarding calcification dispersion but discordant on calcification number. CONCLUSION: There might be more to AAA calcifications that what is known in the present literature. We need larger prospective studies to investigate if indeed, calcification dispersion affects rupture risk. CLINICAL RELEVANCE STATEMENT: Ruptured aneurysms are possibly more likely to have their calcification volume concentrated in a smaller geographical area. KEY POINTS: • Abdominal aortic aneurysm (AAA) rupture prediction based on sex and diameter could be improved. • For a given calcification volume, AAAs with well-distributed calcification clusters could be less likely to rupture. • A machine learning model including AAA calcifications better predicts rupture compared to a model based solely on maximal diameter and sex alone, although it might be prone to overfitting.

Comparison of Radiologists and Deep Learning for US Grading of Hepatic Steatosis.

Background Screening for nonalcoholic fatty liver disease (NAFLD) is suboptimal due to the subjective interpretation of US images. Purpose To evaluate the agreement and diagnostic performance of radiologists and a deep learning model in grading hepatic steatosis in NAFLD at US, with biopsy as the reference standard. Materials and Methods This retrospective study included patients with NAFLD and control patients without hepatic steatosis who underwent abdominal US and contemporaneous liver biopsy from September 2010 to October 2019. Six readers visually graded steatosis on US images twice, 2 weeks apart. Reader agreement was assessed with use of κ statistics. Three deep learning techniques applied to B-mode US images were used to classify dichotomized steatosis grades. Classification performance of human radiologists and the deep learning model for dichotomized steatosis grades (S0, S1, S2, and S3) was assessed with area under the receiver operating characteristic curve (AUC) on a separate test set. Results The study included 199 patients (mean age, 53 years ± 13 [SD]; 101 men). On the test set (n = 52), radiologists had fair interreader agreement (0.34 [95% CI: 0.31, 0.37]) for classifying steatosis grades S0 versus S1 or higher, while AUCs were between 0.49 and 0.84 for radiologists and 0.85 (95% CI: 0.83, 0.87) for the deep learning model. For S0 or S1 versus S2 or S3, radiologists had fair interreader agreement (0.30 [95% CI: 0.27, 0.33]), while AUCs were between 0.57 and 0.76 for radiologists and 0.73 (95% CI: 0.71, 0.75) for the deep learning model. For S2 or lower versus S3, radiologists had fair interreader agreement (0.37 [95% CI: 0.33, 0.40]), while AUCs were between 0.52 and 0.81 for radiologists and 0.67 (95% CI: 0.64, 0.69) for the deep learning model. Conclusion Deep learning approaches applied to B-mode US images provided comparable performance with human readers for detection and grading of hepatic steatosis. Published under a CC BY 4.0 license. Supplemental material is available for this article. See also the editorial by Tuthill in this issue.

Superior photo-induced antibacterial/antibiofilm activities of ZnPcs/TiO2 and computational simulation studies.

Bacteria can form biofilms on any surface, which causes biofilm-associated infections and bacterial resistance to antibiotics. Thus, it is important to design new-generation non-chemotherapeutic nanoagents for effective antibacterial and antibiofilm strategies. Herein, the effects of the anchoring groups, which are imidazole and carboxylic acid, of zinc phthalocyanines (ZnPcs) sensitized TiO2 on Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) were investigated under light-emitting diode (LED) irradiation. The photocatalytic antibacterial activities of ZnPc-1/TiO2 and ZnPc-2/TiO2 on the bacterial strains were examined by monitoring the optical density value at 600 nm (OD600 nm). Glutathione (GSH) oxidation assay was used to measure the reactive oxygen species (ROS) generation activity of the compounds. Bacterial damages were imaged by scanning electron microscopy (SEM). According to our photocatalytic antibacterial mechanism, photogenerated electrons are transferred from Pcs to TiO2 and then react with O2, thus creating ROS, which causes damage to bacterial membrane, protein and biofilm destruction as well. Further, computational simulation analysis was used to show the interaction patterns of ZnPc-1 and ZnPc-2 with penicillin binding protein 2a (PBP2a) of S. aureus and FimH lectin protein (PDB:4XO8) of E. coli to elucidate the dark molecular antibacterial mechanism of the compounds. The obtained results from computational studies showed that ZnPc-2 binds firmly through bonds with the 1MWT protein from S. aureus. On the other hand, ZnPc-1 binds firmly through bonds with the 4XO8 protein from E. coli. From combining experimental and computational results, we can conclude that this strategy can be applied to different types of bacterial infections.

Dataset of PY53 Nickel-Titanate yellow pigments for plastic, enamel and ceramic glaze applications.

This dataset shows the change in color tone in plastic (masterbatch), enamel, and ceramic (glaze) colored with PY53 Nickel-Titanate-Pigment calcined with different NiO ratios by solid-state reaction. The pigments were mixed with milled frits and applied to the metal and ceramic substance for enamel and ceramic glaze applications, respectively. For the plastic application, the pigments were mixed with melted polypropylene (PP) and formed into plastic plates. The CIELAB color space approach was used to assess L*, a*, b* values over applications created for plastic, ceramic, and enamel trials. These data can be used to evaluate the color of PY53 Nickel-Titanate pigments with different NiO ratios in the applications.

Imidazole substituted Zinc(II) phthalocyanines for co-catalyst-free photoelectrochemical and photocatalytic hydrogen evolution: influence of the anchoring group.

Novel zinc phthalocyanine derivatives, ZnPc-1 and ZnPc-2, consisting of one and four imidazole units, respectively, have been synthesized and utilized as panchromatic photosensitizers for photocatalytic and photoelectrochemical H2 evolution. The effect of the imidazole-anchoring group on the photocatalytic H2 production has been compared with ZnPc-3, which possesses a carboxylic acid unit as the anchoring group. ZnPc-1/TiO2 shows the best photoactivity with the highest H2 evolution rate of 0.4006 mmol g-1 h-1, which is much higher than that of ZnPc-2/TiO2 and ZnPc-3/TiO2 (0.3319 mmol g-1 h-1 and 0.3555 mmol g-1 h-1, respectively). After 20 h of irradiation, ZnPc-1 produces an H2 production rate of 3.4187 mmol g-1 with a turnover number (TON) of 14863 and a solar-to-hydrogen energy (STH) conversion efficiency of 1.03%, without using a co-catalyst.

MRI-based R2* mapping in patients with suspected or known iron overload.

PURPOSE: R2* relaxometry is a quantitative method for assessment of iron overload. The purpose is to analyze the cross-sectional relationships between R2* in organs across patients with primary and secondary iron overload. Secondary analyses were conducted to analyze R2* according to treatment regimen. METHODS: This is a retrospective, cross-sectional, institutional review board-approved study of eighty-one adult patients with known or suspected iron overload. R2* was measured by segmenting the liver, spleen, bone marrow, pancreas, renal cortex, renal medulla, and myocardium using breath-hold multi-echo gradient-recalled echo imaging at 1.5 T. Phlebotomy, transfusion, and chelation therapy were documented. Analyses included correlation, Kruskal-Wallis, and post hoc Dunn tests. p < 0.01 was considered significant. RESULTS: Correlations between liver R2* and that of the spleen, bone marrow, pancreas, and heart were respectively 0.49, 0.33, 0.27, and 0.34. R2* differed between patients with primary and secondary overload in the liver (p < 0.001), spleen (p < 0.001), bone marrow (p < 0.01), renal cortex (p < 0.001), and renal medulla (p < 0.001). Liver, spleen, and bone marrow R2* were higher in thalassemia than in hereditary hemochromatosis (all p < 0.01). Renal cortex R2* was higher in sickle cell disease than in hereditary hemochromatosis (p < 0.001) and in thalassemia (p < 0.001). Overall, there was a trend toward lower liver R2* in patients assigned to phlebotomy and higher liver R2* in patients assigned to transfusion and chelation therapy. CONCLUSION: R2* relaxometry revealed differences in degree or distribution of iron overload between organs, underlying etiologies, and treatment.

Subphthalocyanine-sensitized TiO2 photocatalyst for photoelectrochemical and photocatalytic hydrogen evolution.

A series of SubPcs comprising a carboxylic acid anchoring group at the peripheral (SubPcs 1, 2) or axial position (SubPc 3) were synthesized and used as sensitizers for photocatalytic H2 production, for the first time. SubPc 3/TiO2 shows the best photocatalytic activity with a hydrogen evolution rate of 1396 µmol h-1, which is much higher than that of SubPcs 1 and 2 (771 and 658 µmol g-1, respectively). This work clearly shows that considering their optical and redox properties, SubPcs are promising candidates for light-driven water splitting systems.

Hydrogen Evolution Catalyzed by Cu2WS4 at Liquid-Liquid Interfaces.

The present study reports, for the first time, both a facile synthesis for ternary Cu2WS4 nanocubes, which were synthesized by a simple and low-cost hot-injection method, and the hydrogen evolution reaction at a biomembrane-like polarized water/1,2-dichloroethane interface catalyzed by Cu2WS4 nanocubes. The rate of hydrogen evolution reaction is increased by about 1000 times by using Cu2WS4 nanocubes when compared to an uncatalyzed reaction.

Highly Active Cobalt Sulfide/Carbon Nanotube Catalyst for Hydrogen Evolution at Soft Interfaces.

Hydrogen evolution at polarized liquid-liquid interfaces [water/1,2-dichloroethane (DCE)] by the electron donor decamethylferrocene (DMFc) is catalyzed efficiently by the fabricated cobalt sulfide (CoS) nanoparticles and nanocomposites of CoS nanoparticles formed on multi-walled carbon nanotubes (CoS/CNT). The suspended CoS/CNT nanocomposite catalysts at the interface show a higher catalytic activity for the hydrogen evolution reaction (HER) than the CoS nanoparticles due to the high dispersity and conductivity of the CNT materials, which can serve as the main charge transport pathways for the injection of electrons to attain the catalytic sites of the nanoparticles. The reaction rate increased more than 1000-fold and 300-fold by using CoS/CNT and CoS catalysts, respectively, when compared to a non-catalyzed reaction.

Dye-Sensitized Cu2 XSnS4 (X=Zn, Ni, Fe, Co, and Mn) Nanofibers for Efficient Photocatalytic Hydrogen Evolution.

The photocatalytic hydrogen evolution activities of low-cost and noble-metal-free Cu2 XSnS4 (X=Zn, Ni, Fe, Co, and Mn) nanofiber catalysts have been investigated using triethanolamine as an electron donor and eosin Y as a photosensitizer under visible-light irradiation. The rates of hydrogen evolution by Cu2 XSnS4 (X=Zn, Ni, Fe, Co, and Mn) nanofibers have been compared with each other and with that of the noble metal Pt. The hydrogen evolution rates for the nanofibers change in the order Cu2 NiSnS4 >Cu2 FeSnS4 >Cu2 CoSnS4 >Cu2 ZnSnS4 >Cu2 MnSnS4 (2028, 1870, 1926, 1420, and 389 µmol g(-1) h(-1) , respectively). The differences between the hydrogen evolution rates of the nanofibers could be attributed to their energy levels. Moreover, Cu2 NiSnS4, Cu2 FeSnS4 , and Cu2 CoSnS4 nanofibers show higher and more stable photocatalytic hydrogen production rates than that of the noble metal Pt under long-term irradiation with visible light.

Cu nanoparticles electrodeposited at liquid-liquid interfaces: a highly efficient catalyst for the hydrogen evolution reaction.

The electrochemical deposition of Cu nanoparticles with an average diameter of approximately 25-35 nm has been reported at liquid-liquid interfaces by using the organic-phase electron-donor decamethylferrocene (DMFc). The electrodeposited Cu nanoparticles display excellent catalytic activity for the hydrogen evolution reaction (HER); this is the first reported catalytic effect of Cu nanoparticles at liquid-liquid interfaces.

Photocatalytic hydrogen evolution by oleic acid-capped CdS, CdSe, and CdS0.75Se0.25 alloy nanocrystals.

Photocatalytic generation of hydrogen by using oleic acid-capped CdS, CdSe, and CdS(0.75)Se(0.25) alloy nanocrystals (quantum dots) has been investigated under visible-light irradiation by employing Na(2)S and Na(2)SO(3) as hole scavengers. Highly photostable CdS(0.75)Se(0.25) alloy nanocrystals gave the highest hydrogen evolution rate (1466 µmol h(-1) g(-1)), which was about three times higher than that of CdS and seven times higher than that of CdSe.