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Journal of Biomedical Optics Aug 2023X-ray imaging is frequently used for gastrointestinal imaging. Photoacoustic imaging (PAI) of the gastrointestinal tract is an emerging approach that has been...
SIGNIFICANCE
X-ray imaging is frequently used for gastrointestinal imaging. Photoacoustic imaging (PAI) of the gastrointestinal tract is an emerging approach that has been demonstrated for preclinical imaging of small animals. A contrast agent active in both modalities could be useful for imaging applications.
AIM
We aimed to develop a dual-modality contrast agent comprising an admixture of barium sulfate with pigments that absorb light in the second near-infrared region (NIR-II), for preclinical imaging with both x-ray and PAI modalities.
APPROACH
Eleven different NIR-II dyes were evaluated after admixture with a 40% w/v barium sulfate mixture. The resulting NIR-II absorption in the soluble fraction and in the total mixture was characterized. Proof-of-principle imaging studies in mice were carried out.
RESULTS
Pigments that produced more uniform suspensions were assessed further for photoacoustic contrast signal at a wavelength of 1064 nm that corresponds to the output of the Nd:YAG laser used. Phantom imaging studies demonstrated that the pigment-barium sulfate mixture generated imaging contrast in both x-ray and PAI modalities. The optimal pigment selected for further study was a cyanine tetrafluoroborate salt. and whole-body mouse imaging demonstrated that photoacoustic and x-ray contrast signals co-localized in the intestines for both imaging modalities.
CONCLUSION
These data demonstrate that commercially-available NIR-II pigments can simply be admixed with barium sulfate to generate a dual-modality contrast agent appropriate for small animal gastrointestinal imaging.
Topics: Mice; Animals; Barium Sulfate; Contrast Media; X-Rays; Radiography; Spectrum Analysis; Photoacoustic Techniques
PubMed: 36776721
DOI: 10.1117/1.JBO.28.8.082803 -
Scientific Reports Dec 2023Barium sulfate and iohexol are commonly used as contrast agents for videofluoroscopic swallowing study (VFSS). This study compared their usefulness as contrast agents in... (Randomized Controlled Trial)
Randomized Controlled Trial
Barium sulfate and iohexol are commonly used as contrast agents for videofluoroscopic swallowing study (VFSS). This study compared their usefulness as contrast agents in visualizing components of swallowing predictable of subsequent pneumonia and unintentional weight loss after VFSS. This was a randomized, controlled, crossover trial. The two contrast agents were alternately used in the same participants, and the order in which the contrast agent was tested first was randomly assigned. After VFSS, we followed the participants for 3 months and the association between VFSS findings of each contrast agent and the subsequent pneumonia and unintentional weight loss were analyzed. A total of 30 participants were included in the analysis. We recorded 11 cases of subsequent pneumonia and 13 of unintentional weight loss. Regarding the risk of subsequent pneumonia after VFSS, only the oral transit time and number of swallows tested with barium sulfate indicated significant differences between participants with and without subsequent pneumonia. For unintentional weight loss, oral transit time and pharyngeal wall coating after swallowing tested with barium sulfate, as well as oral transit time, nasal penetration, residue in the valleculae, PAS scores, and number of swallows when testing with iohexol demonstrated significant differences between those with and without unintentional weight loss.
Topics: Humans; Barium Sulfate; Contrast Media; Deglutition; Deglutition Disorders; Fluoroscopy; Iohexol; Pneumonia; Video Recording; Weight Loss; Cross-Over Studies
PubMed: 38057481
DOI: 10.1038/s41598-023-46297-4 -
RSC Advances Nov 2023Barium sulfate (BaSO) scale is dense and hard, making it difficult to remove using conventional acid and alkali treatments. Diethylenetriaminepentaacetic acid (DTPA) and...
Barium sulfate (BaSO) scale is dense and hard, making it difficult to remove using conventional acid and alkali treatments. Diethylenetriaminepentaacetic acid (DTPA) and its complexes have been identified as important chelating agents for the removal of BaSO scale. However, DTPA has good solubility only under strong alkali conditions, which in turn exacerbate scaling. To improve the solubility and chelation effectiveness of DTPA, penta sodium diethylenetriamine-pentaacetate (DTPA-5Na) was synthesized using chloroacetic acid, diethylenetriamine, sodium carbonate, and sodium hydroxide as raw materials. The structure of DTPA-5Na was characterized by infrared spectroscopy and H-NMR, and its chelation effectiveness was evaluated. Experimentation demonstrated that under conditions of 50 °C and with a molar ratio of chloroacetic acid (ClCHCOOH), sodium carbonate (NaCO), sodium hydroxide (NaOH), and diethylenetriamine (DETA) of 5.00 : 2.50 : 5.25 : 1.00, the reaction for 6 hours resulted in the optimal chelation value of DTPA-5Na at 76.8 mg CaCO·per g. Analysis of the chelation and dissolution of BaSO scale using DTPA-5Na and microstructural scanning electron microscopy of the BaSO crystal indicate that DTPA-5Na functions through solubilization, lattice distortion, and flaking dispersion to remove BaSO. Molecular dynamics simulation software was used to simulate the chelation mechanism of DTPA-5Na, where the results indicated strong adsorption of DTPA-5Na to the surface of BaSO. The adsorption energy follows the order of (120) surface > (001) surface > (100) surface > (210) surface. The adsorption is mainly a result of the interaction between the carboxylic "O" atom in DTPA-5Na and the (001), (100), and (120) surfaces of BaSO scale, while N atoms in DTPA-5Na structure primarily interact with the (210) surface. The adsorption of "O" atoms is stronger than that of "N" atoms in the DTPA-5Na structure.
PubMed: 38024965
DOI: 10.1039/d3ra05564g -
ACS Omega Jun 2023There are few measurements of barium sulfate (BaSO) solubility in water above 373 K available in the literature. BaSO solubility data at water saturation pressure are...
There are few measurements of barium sulfate (BaSO) solubility in water above 373 K available in the literature. BaSO solubility data at water saturation pressure are scare. The pressure dependence on BaSO solubility has not previously been comprehensively reported for the pressure range 100-350 bar. In this work, an experimental apparatus was designed and built to measure BaSO solubility in aqueous solutions under high-pressure (HP), high-temperature (HT) conditions. The solubility of BaSO was experimentally determined in pure water over the temperature range from = (323.1 to 440.1) K and pressures ranging from = (1 to 350) bar. Most of the measurements were done at water saturation pressure: six data points were done above the saturation pressure (323.1-373.1 K) and 10 experiments were conducted at water saturation (373.1-440.1 K). The reliability of the extended UNIQUAC model and results generated in this work was demonstrated by comparing with the scrutinized experimental data reported in the literature. The model gives a very good agreement with BaSO equilibrium solubility data, demonstrating the reliability of the extended UNIQUAC model. The accuracy of the model at high temperature and saturated pressure due to data insufficiencies is discussed.
PubMed: 37332793
DOI: 10.1021/acsomega.3c00647 -
Polymers Nov 2023The radiological protection has the purpose of safeguarding the physical well-being of the user, preventing exposure to detrimental levels of ionizing radiation. This...
The radiological protection has the purpose of safeguarding the physical well-being of the user, preventing exposure to detrimental levels of ionizing radiation. This study introduces a novel, cost-effective category of lead-free elastomeric material designed for radiation shielding. The filler compounds utilized are notably lighter than conventional lead-based materials, enhancing user ergonomics during application. They comprise of a blend of barium sulfate combined or not with magnesium oxide with addition-cure liquid silicone rubber. To ensure the effectiveness of the radiation shielding, X-ray transmission measurements were performed for the different thicknesses of the materials and the results compared with Monte Carlo simulations. Additionally, the physical properties of the new materials, such as density, homogeneity, tensile strength, viscosity, and wettability, were also evaluated. The findings indicate that both materials fulfill the requirement for application in radiation protection garments.
PubMed: 38006106
DOI: 10.3390/polym15224382 -
MethodsX Jun 2024Sulfate is the fourth most abundant anion in circulation. Despite being an essential nutrient for healthy growth and development, sulfate is not routinely measured in...
Sulfate is the fourth most abundant anion in circulation. Despite being an essential nutrient for healthy growth and development, sulfate is not routinely measured in clinical settings. In research settings, animal studies have shown that hyposulfatemia and hypersulfaturia are associated with adverse developmental outcomes. Those findings have increased interest in measuring plasma and urine sulfate levels. In this study, we describe a modified assay to measure sulfate in low volumes of plasma and urine. •A streamlined microassay to measure sulfate levels using a microtiter plate format was developed.•To determine the robustness of the assay, this method assessed reagent stability and concentrations, as well as absorbance at different wavelengths and following a range of incubation times.•The optimized microassay was used to measure sulfate level in pig plasma and urine samples, which were compared to a validated ion chromatography method.
PubMed: 38660038
DOI: 10.1016/j.mex.2024.102712 -
Pharmacological Research Nov 2023The most recent and promising therapeutic strategies for inflammatory bowel disease (IBD) have engaged biologics targeting single effector components involved in major...
The most recent and promising therapeutic strategies for inflammatory bowel disease (IBD) have engaged biologics targeting single effector components involved in major steps of the immune-inflammatory processes, such as tumor necrosis factor, interleukins or integrins. Nevertheless, these molecules have not yet met expectations regarding efficacy and safety, resulting in a significant percentage of refractory or relapsing patients. Thus, novel treatment options are urgently needed. The minor isoform of the complement inhibitor C4b-binding protein, C4BP(β-), has been shown to confer a robust anti-inflammatory and immunomodulatory phenotype over inflammatory myeloid cells. Here we show that C4BP(β-)-mediated immunomodulation can significantly attenuate the histopathological traits and preserve the intestinal epithelial integrity in dextran sulfate sodium (DSS)-induced murine colitis. C4BP(β-) downregulated inflammatory transcripts, notably those related to neutrophil activity, mitigated circulating inflammatory effector cytokines and chemokines such as CXCL13, key in generating ectopic lymphoid structures, and, overall, prevented inflammatory immune cell infiltration in the colon of colitic mice. PRP6-HO7, a recombinant curtailed analogue with only immunomodulatory activity, achieved a similar outcome as C4BP(β-), indicating that the therapeutic effect is not due to the complement inhibitory activity. Furthermore, both C4BP(β-) and PRP6-HO7 significantly reduced, with comparable efficacy, the intrinsic and TLR-induced inflammatory markers in myeloid cells from both ulcerative colitis and Crohn's disease patients, regardless of their medication. Thus, the pleiotropic anti-inflammatory and immunomodulatory activity of PRP6-HO7, able to "reprogram" myeloid cells from the complex inflammatory bowel environment and to restore immune homeostasis, might constitute a promising therapeutic option for IBD.
Topics: Animals; Humans; Mice; Anti-Inflammatory Agents; Colitis; Immunomodulation; Inflammation; Inflammatory Bowel Diseases; Myeloid Cells
PubMed: 37806602
DOI: 10.1016/j.phrs.2023.106948