Recent Advancements in Ultrasound Contrast Agents Based on Nanomaterials for Imaging.

Ultrasound (US) is a type of mechanical wave that is capable of transmitting energy through biological tissues. By utilization of various frequencies and intensities, it can elicit specific biological effects. US imaging (USI) technology has been continuously developed with the advantages of safety and the absence of radiation. The advancement of nanotechnology has led to the utilization of various nanomaterials composed of both organic and inorganic compounds as ultrasound contrast agents (UCAs). These UCAs enhance USI, enabling real-time monitoring, diagnosis, and treatment of diseases, thereby facilitating the widespread adoption of UCAs in precision medicine. In this review, we introduce various UCAs based on nanomaterials for USI. Their principles can be roughly divided into the following categories: carrying and transporting gases, endogenous gas production, and the structural characteristics of the nanomaterial itself. Furthermore, the synergistic benefits of US in conjunction with various imaging modalities and their combined application in disease monitoring and diagnosis are introduced. In addition, the challenges and prospects for the development of UCAs are also discussed.

Is there added value of the hepatobiliary phase of MRI with hepatobiliary contrast agents for hepatocellular carcinoma diagnosis? A meta-analysis.

Purpose: So far, there have been published several meta-analyses which focused on hepatocellular carcinoma (HCC) detection with hepatobiliary phase (HBP) contrast agents. However, only a few of them aimed at establishing whether there is any added value of the HBP itself for HCC diagnosis. To answer the question, we performed a systematic literature search with the time limit going back to 2010. Material and methods: True positive, false positive, false negative, and true negative values with and without the HBP were extracted from the included studies. Pooled sensitivities and specificities with and without the HBP were calculated and summary receiver operating characteristics curves were drawn to assess the diagnostic performance of the studies with and without the HBP. Results: A total of 13 studies were included involving 1184 HCC lesions. In 13 studies without the HBP, the pooled sensitivity, specificity, and area under the curve (AUC) were 0.83, 0.89 and 0.94 respectively. In 13 studies with the HBP, the pooled sensitivity, specificity and AUC were 0.91, 0.85 and 0.98 respectively. Conclusions: We found no statistically significant differences in sensitivities between studies with and without the HBP (p = 0.1651).

Tracking the distribution of persistent and mobile wastewater-derived substances in the southern and central North Sea using anthropogenic gadolinium from MRI contrast agents as a far-field tracer.

The use of the rare earth element gadolinium (Gd) in contrast agents for magnetic resonance imaging has led to a significant (micro-)contamination of riverine and coastal environments in many parts of the world. This study comprises a detailed investigation on the rare earth elements and yttrium inventory of the North Sea and also reports data for the major tributaries Thames, Rhine, Ems, Weser and Elbe. We show that large parts of the southern North Sea, including the Wadden Sea UNESCO Natural World Heritage site, are (micro)contaminated with Gd from Gd-based contrast agents (GBCA). Their dispersion reveals their estuarine input and allows to effectively track water masses and currents. The chemical persistence and conservative behavior of GBCA, coupled with the low detection limits of state-of-the-art analytical methods, makes the anthropogenic Gd a sensitive screening proxy for monitoring similarly stable, but potentially hazardous, persistent chemical/pharmaceutical substances in natural waters.

Cyclotron production of manganese-52: a promising avenue for multimodal PET/MRI imaging.

BACKGROUND: The integration of positron emission tomography (PET) and magnetic resonance imaging (MRI) holds promise for advancing diagnostic imaging capabilities. The METRICS project aims to develop cyclotron-driven production of 52Mn for PET/MRI imaging. RESULTS: Using the 52Cr(p,n)52Mn reaction, we designed chromium metal targets via Spark Plasma Sintering and developed a separation procedure for isolating 52Mn. Labeling tests were conducted with traditional chelators (i.e. S-2-(4-Isothiocyanatobenzyl)-1,4,7,10-tetraazacyclododecane tetraacetic acid) and the 1.4-dioxa-8-azaspiro[4.5]decane-8- carbodithioate ligand to produce radioactive complexes suitable for PET/MRI applications. Our methodology yielded high-quality 52Mn suitable for PET radiopharmaceuticals and PET/MRI imaging. Preliminary studies on phantom imaging using microPET and clinical MRI demonstrated the efficacy of our approach. CONCLUSIONS: The developed technology offers a promising avenue for producing 52Mn and enhancing PET/MRI imaging capabilities. Further in vivo investigations are warranted to evaluate the potential advantages of this hybrid imaging technique.

Differences in hypersensitivity reactions and gadolinium deposition disease/symptoms associated with gadolinium exposure to gadolinium-based contrast agents: new insights based on global databases VigiBase, FAERS, and IQVIA-MIDAS.

BACKGROUND: Hypersensitivity reactions (HSRs) can occur unexpectedly and be life-threatening when gadolinium-based contrast agents (GBCAs) are used. Gadolinium deposition disease (GDD) and symptoms associated with gadolinium exposure (SAGE) have been controversial for a long time. However, similar studies are currently incomplete or outdated. Therefore, comparing the safety of different GBCAs in terms of HSRs and GDD/SAGE using the latest post-marketing safety data should yield further insights into safely using GBCAs. METHODS: The safety differences between all GBCAs to GDD and the spectrum of GBCA-related HSRs were all compared and analyzed by using the World Health Organization database VigiBase and the FDA Adverse Event Reporting System (FAERS) database in this study. A further analysis of SAGE was also conducted using FAERS data. The lower limit of the reporting odds ratio (ROR) 95% confidence interval was used for signal detection. Moreover, the frequency of HSRs was calculated by dividing the number of reports in VigiBase by the total sales volume (measured in millions) from 2008 to 2022 in the IQVIA Multinational Integrated Data Analysis System. All adverse events were standardized using the Medical Dictionary for Drug Regulatory Activities (MedDRA) 26.0. RESULTS: This study shows that all GBCAs have the potential to induce HSRs, with nonionic linear GBCAs exhibiting a comparatively lower signal. According to standardized MedDRA query stratification analysis, gadobutrol had a greater ROR025 for angioedema. The ROR025 of gadobenate dimeglumine and gadoteridol is larger for anaphylactic/anaphylactoid shock conditions. Regarding severe cutaneous adverse reactions, only gadoversetamide and gadodiamide showed signals in FAERS and VigiBase. There were also differences in the frequency of HSRs between regions. Regarding GDD, gadoterate meglumine, and gadoteridol had a lower ROR025. An analysis of the 29 preferred terms linked to SAGE indicated that special consideration should be given to the risk of skin induration associated with gadoversetamide, gadopentetate dimeglumine, gadobenate dimeglumine, gadodiamide, and gadoteridol. Additionally, gadodiamide and gadoteridol pose a greater risk of skin tightness compared to other GBCAs. CONCLUSIONS: The risk differences among GBCAs using data from several sources were compared in this study. However, as a hypothesis-generating method, a clear causal relationship would require further research and validation.

Turn-table micro-CT scanner for dynamic perfusion imaging in mice: design, implementation, and evaluation.

Objective.This study introduces a novel desktop micro-CT scanner designed for dynamic perfusion imaging in mice, aimed at enhancing preclinical imaging capabilities with high resolution and low radiation doses.Approach.The micro-CT system features a custom-built rotating table capable of both circular and helical scans, enabled by a small-bore slip ring for continuous rotation. Images were reconstructed with a temporal resolution of 3.125 s and an isotropic voxel size of 65µm, with potential for higher resolution scanning. The system's static performance was validated using standard quality assurance phantoms. Dynamic performance was assessed with a custom 3D-bioprinted tissue-mimetic phantom simulating single-compartment vascular flow. Flow measurements ranged from 1.51to 9 ml min-1, with perfusion metrics such as time-to-peak, mean transit time, and blood flow index calculated.In vivoexperiments involved mice with different genetic risk factors for Alzheimer's and cardiovascular diseases to showcase the system's capabilities for perfusion imaging.Main Results.The static performance validation confirmed that the system meets standard quality metrics, such as spatial resolution and uniformity. The dynamic evaluation with the 3D-bioprinted phantom demonstrated linearity in hemodynamic flow measurements and effective quantification of perfusion metrics.In vivoexperiments highlighted the system's potential to capture detailed perfusion maps of the brain, lungs, and kidneys. The observed differences in perfusion characteristics between genotypic mice illustrated the system's capability to detect physiological variations, though the small sample size precludes definitive conclusions.Significance.The turn-table micro-CT system represents a significant advancement in preclinical imaging, providing high-resolution, low-dose dynamic imaging for a range of biological and medical research applications. Future work will focus on improving temporal resolution, expanding spectral capabilities, and integrating deep learning techniques for enhanced image reconstruction and analysis.

Adding contrast-enhanced ultrasound can improve the predictive ability of breast conventional ultrasound and mammography for pathological upgrade of biopsy-confirmed ductal carcinoma in situ.

OBJECTIVES: To evaluate the added value of contrast-enhanced ultrasound (CEUS) on top of breast conventional imaging for predicting the upgrading of ductal carcinoma in situ (DCIS) to invasive cancer after surgery. METHODS: This retrospective study enrolled 140 biopsy-proven DCIS lesions in 138 patients and divided them into two groups based on postoperative histopathology: non-upgrade and upgrade groups. Conventional ultrasound (US), mammography (MMG), CEUS and clinicopathological (CL) features were reviewed and compared between the two groups. The predictive performance of different models (with and without CEUS features) for histologic upgrade were compared to calculate the added value of CEUS. RESULTS: Fifty-nine (42.1 %) lesions were histologically upgraded to invasive cancer after surgery. By logistic regression analyses, we found that high-grade DCIS at biopsy (P=0.004), ultrasonographic lesion size > 20 mm (P=0.007), mass-like lesion on US (P=0.030), the presence of suspicious calcification on MMG (P=0.014), the presence of perfusion defect (P=0.005) and the area under TIC>1021.34 ml (P<0.001) on CEUS were six independent factors predicting concomitant invasive components after surgery. The CL+US+MMG model made with the four predictors in the clinicopathologic, US and MMG categories yielded an area under the receiver operating curve (AUROC) value of 0.759 (95 % CI: 0.680-0.828) in predicting histological upgrade. The combination model built by adding the two CEUS predictors to the CL+US+MMG model showed higher predictive efficacy than the CL+US+MMG model (P=0.018), as the AUROC value was improved to 0.861 (95 % CI: 0.793-0.914). CONCLUSIONS: The addition of contrast-enhanced ultrasound to breast conventional imaging could improve the preoperative prediction of an upgrade to invasive cancer from CNB -proven DCIS lesions.

Perovskites as Multiphoton Fluorescence Contrast Agents for In Vivo Imaging.

Multiphoton fluorescence microscopy is a powerful tool for imaging and exploring biological tissue at subcellular spatial resolution while minimizing photobleaching and autofluorescence. For optimal performance in multiphoton microscopy, materials exhibiting a large multiphoton absorption cross section (σn) and fluorescence quantum yield are desired. Notably, perovskite nanocrystals (CsPbX3, PNCs) exhibit exceptionally large two-, three-, up to five photon absorption cross section (σ2 ∼ 106 GM, σ3 ∼ 10-73 cm6s2 photon-2, σ5 ∼ 10-136 cm10s4 photon-4), along with near unity fluorescence quantum yield, making them desirable for deep tissue applications. Here, we employed PNCs as contrast agents to image mesenchymal stromal cells in a living mouse. The PNCs were stabilized by encapsulating them in a SiO2 matrix (∼60-70 nm in diameter), offering versatility for subsequent surface modification to target specific biological entities for both diagnostic and therapeutic applications. Multiphoton imaging of PNCs offers substantial benefits for dynamic tracking of cells in deep tissue, such as in understanding immune cell migration and other biological processes in both healthy and diseased tissues.

Manganese-Loaded Liposomes: An In Vitro Study for Possible Diagnostic Application.

The present study investigates the possible use of manganese (Mn)-based liposomal formulations for diagnostic applications in imaging techniques such as magnetic resonance imaging (MRI), with the aim of overcoming the toxicity limitations associated with the use of free Mn2+. Specifically, anionic liposomes carrying two model Mn(II)-based compounds, MnCl2 (MC) and Mn(HMTA) (MH), were prepared and characterised in terms of morphology, size, loading capacity, and in vitro activity. Homogeneous dispersions characterised mainly by unilamellar vesicles were obtained; furthermore, no differences in size and morphology were detected between unloaded and Mn-loaded vesicles. The encapsulation efficiency of MC and MH was evaluated on extruded liposomes by means of ICP-OES analysis. The obtained results showed that both MC and MH are almost completely retained by the lipid portion of liposomes (LPs), with encapsulation efficiencies of 99.7% for MC and 98.8% for MH. The magnetic imaging properties of the produced liposomal formulations were investigated for application in a potential preclinical scenario by collecting magnetic resonance images of a phantom designed to compare the paramagnetic contrast properties of free MC and MH compounds and the corresponding manganese-containing liposome dispersions. It was found that both LP-MC and LP-MH at low concentrations (0.5 mM) show better contrast (contrast-to-noise ratios of 194 and 209, respectively) than solutions containing free Mn at the same concentrations (117 and 134, respectively) and are safe to use on human cells at the selected dose. Taken together, the results of this comparative analysis suggest that these liposome-containing Mn compounds might be suitable for diagnostic purposes.

MRI contrast agents and retention in the brain: review of contemporary knowledge and recommendations to the future.

Gadolinium-based contrast agents (GBCA) were introduced with high expectations for favorable efficacy, low nephrotoxicity, and minimal allergic-like reactions. Nephrogenic systemic fibrosis and proven gadolinium retention in the body including the brain has led to the restriction of linear GBCAs and a more prudent approach regarding GBCA indication and dosing. In this review, we present the chemical, physical, and clinical aspects of this topic and aim to provide an equanimous and comprehensive summary of contemporary knowledge with a perspective of the future. In the first part of the review, we present various elements and compounds that may serve as MRI contrast agents. Several GBCAs are further discussed with consideration of their relaxivity, chelate structure, and stability. Gadolinium retention in the brain is explored including correlation with the presence of metalloprotein ferritin in the same regions where visible hyperintensity on unenhanced T1-weighted imaging occurs. Proven interaction between ferritin and gadolinium released from GBCAs is introduced and discussed, as well as the interaction of other elements with ferritin; and manganese in patients with impaired liver function or calcium in Fahr disease. We further present the concept that only high-molecular-weight forms of gadolinium can likely visibly change signal intensity on unenhanced T1-weighted imaging. Clinical data are also presented with respect to potential neurological manifestations originating from the deep-brain nuclei. Finally, new contrast agents with relatively high relaxivity and stability are introduced. CRITICAL RELEVANCE STATEMENT: GBCA may accumulate in the brain, especially in ferritin-rich areas; however, no adverse neurological manifestations have been detected in relation to gadolinium retention. KEY POINTS: Gadolinium currently serves as the basis for MRI contrast agents used clinically. No adverse neurological manifestations have been detected in relation to gadolinium retention. Future contrast agents must advance chelate stability and relativity, facilitating lower doses.

A Macrocyclic Hybrid PET/MRI Probe for Quantitative Perfusion Imaging In Vivo.

Perfusion dynamics play a vital role in delivering essential nutrients and oxygen to tissues while removing metabolic waste products. Imaging techniques such as magnetic resonance imaging (MRI), computed tomography (CT), and positron emission tomography (PET) use contrast agents to visualize perfusion and clearance patterns; however, each technique has specific limitations. Hybrid PET/MRI combines the quantitative power and sensitivity of PET with the high functional and anatomical detail of MRI and holds great promise for precision in molecular imaging. However, the development of dual PET/MRI probes has been hampered by challenging synthesis and radiolabeling. Here, we present a novel PET/MRI probe, [18F][Gd(FL1)], which exhibits excellent stability comparable to macrocyclic MRI contrast agents used in clinical practice. The unique molecular design of [18F][Gd(FL1)] allows selective and expeditious radiolabeling of the gadolinium chelate in the final synthetic step. Leveraging the strengths of MRI and PET signals, the probe enables quantitative in vivo mapping of perfusion and excretion dynamics through an innovative voxel-based analysis. The diagnostic capabilities of [18F][Gd(FL1)] were demonstrated in a pilot study on healthy mice, successfully detecting early cases of unilateral renal dysfunction. This study introduces a new approach for PET/MRI and emphasizes a streamlined probe design for improved diagnostic accuracy.

Size-Dependent Oxygen Vacancy of Iron Oxide Nanoparticles.

Prior research has highlighted the reduction of iron oxide nanoparticle (IONPs) sizes to the "ultra-small" dimension as a pivotal approach in developing T1-MRI contrast agents, and the enhancement in T1 contrast performance with the reducing size is usually attributed to the increased specific surface area and weakened magnetization. Nonetheless, as the size decreases, the variation in surface defects, particularly oxygen vacancy (VO) defects, significantly impacts the T1 imaging efficacy. In this study, the VO on IONPs is meticulously investigated through XPS, Raman, and EPR spectroscopy. As the nanoparticle size decreased, the VO concentration rose initially but subsequently declined, with the peak concentration observed in the size of 8.27 nm. Further insights gained from synchrotron XAS analysis and DFT calculations indicate that both surface tension and phase transition in IONPs contribute to alterations in the Fe─O bond length, thereby influencing the VO formation energy across varying nanoparticle sizes. The MRI tests reveal that the VO in IONPs serve as pivotal sites for the attachment of water molecules to iron ions, and IONPs with fewer VO exhibited a deterioration in T1-MRI contrast effects. This research may provide a deeper understanding of the relationship between T1 contrast performance and the size of IONPs.

The behavior of pharmaceutically active compounds and contrast agents during wastewater treatment - Combining sampling strategies and analytical techniques: A critical review.

Increasing consumption of pharmaceuticals and the respective consequences for the aquatic environment have been the focus of many studies over the last thirty years. Various aspects in this field were investigated, considering diverse pharmaceutical groups and employing a wide range of research methodologies. Various questions from the perspectives of different research areas were devised and answered, resulting in a large mix of individual findings and conclusions. Collectively, the results of the studies offer a comprehensive overview. The large variety of methods and strategies, however, demands close attention when comparing and combining information from heterogeneous projects. This review critically examines the application of diverse sampling techniques as well as analytical methods in investigations concerning the behavior of pharmaceutically active compounds (PhACs) and contrast agents (CAs) in wastewater treatment plants (WWTPs). The combination of sampling and analysis is discussed with regard to its suitability for specific scientific problems. Different research focuses need different methods and answer different questions. An overview of studies dealing with the fate and degradation of PhACs and CAs in WWTPs is presented, discussing their strategic approaches and findings. This review includes surveys of anticancer drugs, antibiotics, analgesics and anti-inflammatory drugs, antidiabetics, beta blockers, hormonal contraceptives, lipid lowering agents, antidepressants as well as contrast agents for X-ray and magnetic resonance imaging.

Regulating interparticle proximity in plasmonic nanosphere aggregates to enhance photoacoustic response and photothermal stability.

Designing plasmonic nanoparticles for biomedical photoacoustic (PA) imaging involves tailoring material properties at the nanometer scale. A key in developing plasmonic PA contrast nanoagents is to engineer their enhanced optical responses in the near-infrared wavelength range, as well as heat transfer properties and photostability. This study introduces anisotropic plasmonic nanosphere aggregates with close interparticle proximity as photostable and efficient contrast agent for PA imaging. Silver (Ag), among plasmonic metals, is particularly attractive due to its strongest optical response and highest heat conductivity. Our results demonstrate that close interparticle proximity in silver nanoaggregates (AgNAs), spatially confined within a polymer shell layer, leads to blackbody-like optical absorption, resulting in robust PA signals through efficient pulsed heat generation and transfer. Additionally, our AgNAs exhibit a high photodamage threshold highlighting their potential to outperform conventional plasmonic contrast agents for high-contrast PA imaging over multiple imaging sessions. Furthermore, we demonstrate the capability of the AgNAs for molecular PA cancer imaging in vivo by incorporating a tumor-targeting peptide moiety.

[Abnormal thyroid markers in critically ill patients-harmless irritation or a real problem?] / Auffällige Schilddrüsenwerte bei kritisch Kranken ­ harmlose Irritation oder echtes Problem?

BACKGROUND: Abnormal thyroid markers are a frequent occurrence in emergency and intensive care medicine. Correct interpretation of their clinical relevance and distinction from a primary thyroid disease, particularly prior to potential administration of iodine-containing antiarrhythmic drugs such as amiodaron or radiocontrast agents, are both essential and challenging. OBJECTIVE: This article aims to present the pathophysiology of abnormal thyroid markers in acute or protracted critical disease. Their relevance for administration of amiodaron or iodine-containing radiocontrast agents is discussed, and concrete practical recommendations are presented. MATERIALS AND METHODS: The current work comprises a discussion of expert recommendations, guidelines, and basic research. RESULTS AND CONCLUSION: Approximately one third of intensive care patients develop non-thyroidal illness syndrome (NTIS) during the course of their critical disease. NTIS is characterized by a reduction in the serum concentration of fT3 and, during the course, also in those of thyroid-stimulating hormone (TSH) and fT4, despite an organically intact thyroid gland. A greater extent of the deviations correlates with a worse overall prognosis. The mechanisms involved are manifold and influence different levels of hormonal signaling axes. They are mediated by interaction with acute stress signals such as inflammatory factors and elevated cortisol levels and are influenced by medication. The components vary depending on disease severity and the protracted course. NTIS does not require any specific treatment; the focus is on treating the underlying disease. Latent hyperthyroidism in particular must be distinguished from NTIS. In unclear situations and high-risk constellations, perchlorate is indicated before (and after) iodine exposure.

High resolution imaging of human development: shedding light on contrast agents.

BACKGROUND: Visualizing (micro)vascular structures remains challenging for researchers and clinicians due to limitations in traditional radiological imaging methods. Exploring the role of vascular development in craniofacial malformations in experimental settings can enhance understanding of these processes, with the effectiveness of high-resolution imaging techniques being crucial for successful research in this field. Micro-CT imaging offers 3D microstructural insights, but requires contrast-enhancing staining agents (CESAs) for visualizing (micro)-vascular tissues, known as contrast-enhanced micro-CT (CECT). As effective contrast agents are crucial for optimal visualization, this review focuses on comparative studies investigating such agents for micro-vascular tissue imaging using micro-CT. Furthermore, we demonstrate the utilization of B-Lugol solution as a promising contrast agent for acquiring high-quality micro-CT images of (micro)vascular structures in human embryonic samples. METHOD: This scoping review followed Preferred Reporting Items for Systematic Reviews and Meta-analysis Protocols. PubMed database provided relevant articles, screened initially by title and abstract. Inclusion and exclusion criteria defined outcomes of interest. RESULTS: From an initial search, 273 records were identified, narrowed down to 9 articles after applying our criteria. Additionally, two articles were added through citation searching. This, a total of 11 articles were incorporated in this study. CONCLUSION: This micro-CT contrast agent review underscores the need for tailored choices based on research goals. Both Barium sulfate and Iodine-based agents showing excellent results, providing high resolution (micro) vascular content, especially in ex-vivo specimens. However, careful consideration of protocols and tissue characteristics remains imperative for optimizing the effectiveness of micro-CT imaging for the study of cranio-facial vascular development.

Advancements in manganese complex-based MRI agents: Innovations, design strategies, and future directions.

This review focuses on the advancements in manganese (Mn) complex-based magnetic resonance imaging (MRI) agents for imaging different diseases. Here we emphasize the unique redox properties of Mn to deliver innovative MRI contrast agents, including small molecules, nanoparticles (NPs), metal-organic frameworks (MOFs), and polymer hybrids. Aspects of their rational design have been discussed, including size dependence, morphology tuning, surface property enhancement, etc., while also discussing the existing challenges and potential solutions. The present work will inspire and motivate scientists to emphasize MRI-guided applications and bring clinical success in the coming years.

Bismuth drug-inspired ultra-small dextran coated bismuth oxide nanoparticles for targeted computed tomography imaging of inflammatory bowel disease.

Bismuth (Bi)-based computed tomography (CT) imaging contrast agents (CAs) hold significant promise for diagnosing gastrointestinal diseases due to their cost-effectiveness, heightened sensitivity, and commendable biocompatibility. Nevertheless, substantial challenges persist in achieving an easy synthesis process, remarkable water solubility, and effective targeting ability for the potential clinical transformation of Bi-based CAs. Herein, we show Bi drug-inspired ultra-small dextran coated bismuth oxide nanoparticles (Bi2O3-Dex NPs) for targeted CT imaging of inflammatory bowel disease (IBD). Bi2O3-Dex NPs are synthesized through a simple alkaline precipitation reaction using bismuth salts and dextran as the template. The Bi2O3-Dex NPs exhibit ultra-small size (3.4 nm), exceptional water solubility (over 200 mg mL-1), high Bi content (19.75 %), excellent biocompatibility and demonstrate higher X-ray attenuation capacity compared to clinical iohexol. Bi2O3-Dex NPs not only enable clear visualization of the GI tract outline and intestinal loop structures in CT imaging but also specifically target and accumulate at the inflammatory site in colitis mice after oral administration, facilitating a precise diagnosis and enabling targeted CT imaging of IBD. Our study introduces a novel and clinically promising strategy for synthesizing high-performance Bi2O3-Dex NPs for diagnosing gastrointestinal diseases.

Taylor dispersion analysis for measurement of diffusivity and size of gadolinium-based contrast agents.

Gadolinium-based contrast agents (GBCA) are complexes of a Gadolinium metal center and a linear or macrocyclic polyamino-carboxylic acid chelating agent. These agents are employed to enhance the visibility of deep abnormalities through MRI techniques. Knowing the precise dimensions of various GBCA is key parameter for understanding their in-vivo and pharmaco-kinetic behaviors, their diffusivity, as well as their relaxivity. However, conventional size characterization techniques fall short when dealing with these tiny molecules (≤1 nm). In this work, we propose to determine the size and diffusivity of gadolinium-based contrast agents using Taylor dispersion analysis (TDA). TDA provided a reliable measurement of the hydrodynamic diameter and the diffusion coefficient. The obtained results were compared to DOSY NMR (Diffusion-ordered Nuclear Magnetic Resonance Spectroscopy) and DFT (Density Functional Theory).

The Effect of Iodinated Contrast Media Sensitivity on the Prognosis of Patients with STEMI.

Background and Objectives: Iodinated Contrast Media (ICM) is used daily in many imaging departments worldwide. The main risk associated with ICM is hypersensitivity. When a severe hypersensitivity reaction is not properly managed and treated swiftly, it may be fatal. Currently, there is no data to demonstrate how ICM sensitivity affects the prognosis of cardiac patients, especially those diagnosed with ST elevation myocardial infarction (STEMI), in whom urgent coronary angiography is indicated. This study aimed to identify and characterize this relationship. Materials and Methods: We included patients hospitalized with STEMI between 2016 and 2019 from the National Inpatient Sample. The population was compared based on ICM sensitivity status, sensitive vs. non-sensitive. The primary endpoint was in-hospital mortality, with additional endpoints: length of stay and in-hospital complications. Results: The study included 664,620 STEMI patients, of whom 4905 (0.7%) were diagnosed with ICM sensitivity. ICM-sensitive patients were older, more often white, females, and had more comorbidities and cardiovascular risk factors. Both groups show similarities in management but are slightly less probable to undergo PCI or CABG. Multivariable logistic regression models found that the ICM-sensitive population had similar odds of in-hospital mortality (OR: 1.02, 95% CI: 0.89-1.16) and MACCE (OR: 1.05, 95% CI: 0.95-1.16), and less major bleeding (OR: 0.73, 95% CI: 0.60-0.87). Conclusions: Our study found that ICM sensitivity status was not a significant factor for worse prognosis in patients hospitalized with STEMI.