ABSTRACT
Advanced breast cancer remains a significant oncological challenge, requiring new approaches to improve clinical outcomes. This study investigated an innovative theranostic agent using the MCM-41-NH2-DTPA-Gd3âº-MIH nanomaterial, which combined MRI imaging for detection and a novel chemotherapy agent (MIH 2.4Bl) for treatment. The nanomaterial was based on the mesoporous silica type, MCM-41, and was optimized for drug delivery via functionalization with amine groups and conjugation with DTPA and complexation with Gd3+. MRI sensitivity was enhanced by using gadolinium-based contrast agents, which are crucial in identifying early neoplastic lesions. MIH 2.4Bl, with its unique mesoionic structure, allows effective interactions with biomolecules that facilitate its intracellular antitumoral activity. Physicochemical characterization confirmed the nanomaterial synthesis and effective drug incorporation, with 15% of MIH 2.4Bl being adsorbed. Drug release assays indicated that approximately 50% was released within 8 h. MRI phantom studies demonstrated the superior imaging capability of the nanomaterial, with a relaxivity significantly higher than that of the commercial agent Magnevist. In vitro cellular cytotoxicity assays, the effectiveness of the nanomaterial in killing MDA-MB-231 breast cancer cells was demonstrated at an EC50 concentration of 12.6 mg/mL compared to an EC50 concentration of 68.9 mg/mL in normal human mammary epithelial cells (HMECs). In vivo, MRI evaluation in a 4T1 syngeneic mouse model confirmed its efficacy as a contrast agent. This study highlighted the theranostic capabilities of MCM-41-NH2-DTPA-Gd3âº-MIH and its potential to enhance breast cancer management.
Subject(s)
Breast Neoplasms , Magnetic Resonance Imaging , Nanoparticles , Silicon Dioxide , Theranostic Nanomedicine , Silicon Dioxide/chemistry , Animals , Humans , Breast Neoplasms/drug therapy , Breast Neoplasms/diagnostic imaging , Breast Neoplasms/pathology , Female , Theranostic Nanomedicine/methods , Magnetic Resonance Imaging/methods , Mice , Cell Line, Tumor , Nanoparticles/chemistry , Antineoplastic Agents/pharmacology , Antineoplastic Agents/chemistry , Antineoplastic Agents/therapeutic use , Contrast Media/chemistry , Gadolinium/chemistry , Porosity , Xenograft Model Antitumor AssaysABSTRACT
Late gadolinium enhancement (LGE) is a widely used magnetic resonance imaging method for assessing cardiac disease. However, the relationship between different LGE signal thresholds and microscopic tissue staining images is unclear. In this study, we performed cardiovascular MRI on myocardial infarction (MI) model rats and evaluated the relationship between LGE with different signal thresholding methods and tissue staining images. We prepared 16 rats that underwent MRI 14-18 days following a surgery to create an MI model. We captured cine and LGE images of the cardiac short-axis and longitudinal two- and four-chamber views. The mean ± 2SD, ± 3SD, and ± 5SD of the pixel values in the non-infarcted area were defined as the LGE area. We compared areas of Sirius red staining, determined by the color tone, with their respective LGE areas at end-diastole and end-systole. We observed that the LGE area calculated as the mean ± 2SD of the non-infarcted area at end-diastole demonstrated a significant positive correlation with the area of Sirius red staining (Pearson's correlation coefficient in both: 0.81 [p < 0.01]). Therefore, the LGE area calculated as the mean ± 2SD of the non-infarcted area at end-diastole best reflected the MI area in tissue staining.
Subject(s)
Contrast Media , Disease Models, Animal , Gadolinium , Magnetic Resonance Imaging , Myocardial Infarction , Animals , Myocardial Infarction/diagnostic imaging , Myocardial Infarction/pathology , Rats , Magnetic Resonance Imaging/methods , Male , Staining and Labeling/methods , Myocardium/pathology , Rats, Sprague-DawleyABSTRACT
Chemotherapy as a cornerstone of cancer treatment is slowly being edged aside owing to its severe side effects and systemic toxicity. In this case, nanomedicine has emerged as an effective tool to address these drawbacks. Herein, a biocompatible carrier based on bovine serum albumin (BSA) coated gadolinium oxide nanoparticles (Gd2O3@BSA) was fabricated for curcumin (CUR) delivery and its physicochemical features along with its potential anticancer activity against nasal squamous cell carcinoma were also investigated. It was found that the fabricated Gd2O3@BSA containing CUR (Gd2O3@BSA-CUR) had spherical morphology with hydrodynamic size of nearly 26 nm, zeta-potential of -36 mV and high drug (CUR) loading capacity. Drug release profile disclosed that the release of CUR from the prepared Gd2O3@BSA-CUR nanoparticles occurred in a sustained- and pH-dependent manner. Also, in vitro cytotoxicity analysis revealed that the fabricated Gd2O3@BSA nanoparticles possessed excellent biosafety toward HFF2 normal cells, while Gd2O3@BSA-CUR appeared to display the greatest anticancer potential against RPMI 2650 and CNE-1 cancer cell lines. The results also show that the Gd2O3@BSA nanoparticles were compatible with the blood cells with minor hemolytic effect (< 3%). The manufactured NPs were found to be completely safe for biological applications in an in vivo subacute toxicity study. Taken together, these finding substantiate the potential anticancer activity of Gd2O3@BSA-CUR nanoparticles against nasal squamous cell carcinoma, but the results obtained demand further studies to assess their full potential.
Subject(s)
Antineoplastic Agents , Carcinoma, Squamous Cell , Gadolinium , Serum Albumin, Bovine , Gadolinium/chemistry , Gadolinium/pharmacology , Humans , Antineoplastic Agents/pharmacology , Antineoplastic Agents/chemistry , Carcinoma, Squamous Cell/drug therapy , Serum Albumin, Bovine/chemistry , Cell Line, Tumor , Animals , Curcumin/pharmacology , Curcumin/chemistry , Nose Neoplasms/drug therapy , Nanoparticles/chemistry , Metal Nanoparticles/chemistry , Cell Survival/drug effects , Biocompatible Materials/chemistry , Biocompatible Materials/pharmacology , Drug Liberation , Hemolysis/drug effectsABSTRACT
OBJECTIVES: To evaluate the differences between audio-vestibular function testing and inner ear gadolinium magnetic resonance imaging (MRI) in distinguishing definite Ménière disease (DMD) and probable Ménière disease (PMD), and to provide a reference for early clinical diagnosis and intervention. METHODS: A total of 116 patients diagnosed with DMD (n = 80) and PMD (n = 36) were enrolled. The differences in the results of pure tone audiometry, caloric test, and tympanic injection of gadolinium for contrast-enhanced MRI between the two groups were compared and analyzed. Parameters that could differentiate between the two conditions were identified, and the sensitivity and specificity and the area under the curve (AUC) of individual and combined indices in the differential diagnosis of DMD and PMD were evaluated. RESULTS: The hearing threshold and hearing asymmetry rate of the DMD group were significantly higher than those of the PMD group (p < 0.001), 98.8% and 30.6%, respectively. The abnormal rates of canal paresis (CP) and severity of endolymphatic hydrops in the DMD group were higher than those in the PMD group (p < 0.05). When combined with high-frequency hearing thresholds, hearing asymmetry, hearing curve type, endolymphatic hydrops, and abnormal CP, the diagnostic accuracy of DMD was improved compared to using high-frequency alone (p < 0.05). CONCLUSION: This study showed that PMD and DMD may represent two different stages in the development of MD disease. The comprehensive assessment of audio-vestibular function testing and inner ear MRI proves beneficial for early diagnosis, potentially contributing to the preservation of inner ear function.
Subject(s)
Ear, Inner , Magnetic Resonance Imaging , Meniere Disease , Vestibular Function Tests , Humans , Meniere Disease/diagnostic imaging , Meniere Disease/diagnosis , Male , Female , Magnetic Resonance Imaging/methods , Middle Aged , Adult , Ear, Inner/diagnostic imaging , Ear, Inner/physiopathology , Vestibular Function Tests/methods , Aged , Diagnosis, Differential , Audiometry, Pure-Tone/methods , Caloric Tests , Gadolinium , Sensitivity and SpecificityABSTRACT
The GdAl3(BO3)4:xPr3+ (0 ≤ x ≤ 5.0 mol%) phosphors were prepared through solid state reaction route and characterized for various lighting applications. Powder X-ray diffraction investigations revel rhombohedral structure matched to JCPDS card no. 83-1907. The morphological studies confirm the agglomeration of particles with different size and shape. The emission spectra show various emission transitions originating from Pr3+:(3P1,0, 1D2) emission states to their lower lying energy states upon 274 nm NUV excitation with a red shift for x > 0.5 mol%. The colour perception analysis results an intense red luminescence due to efficient energy transfer from Gd3+ to Pr3+ ions. The temperature-dependent luminescence investigations show good thermal stability even beyond 150°C with an activation energy of 0.24 eV. The observed experimental results show the potentiality of GdAl3(BO3)4:0.5 Pr3+ phosphor for red emitting devices and red component in phosphor converted white LEDs.
Subject(s)
Gadolinium , Luminescence , Luminescent Agents , Gadolinium/chemistry , Luminescent Agents/chemistry , Luminescent Measurements , Praseodymium/chemistry , X-Ray Diffraction , Particle Size , Temperature , ColorABSTRACT
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.
Subject(s)
Contrast Media , Databases, Factual , Drug Hypersensitivity , Gadolinium , Humans , Gadolinium/adverse effects , Contrast Media/adverse effects , Drug Hypersensitivity/epidemiology , Adverse Drug Reaction Reporting Systems , United States , World Health OrganizationABSTRACT
Reactions to contrast media are unpredictable. This article examines the use of iodinated and gadolinium-based contrast agents in medical imaging. It explores their clinical presentation, associated risk factors, precautions prior to their administration, and treatment options in the event of a reaction. By highlighting these essential aspects, the article aims to inform healthcare professionals on the safe and effective management of these agents during imaging procedures. The effectiveness of the different premedication protocols proposed in the literature has not yet been established. In particular, premedication does not prevent serious allergic reactions.
Les réactions aux produits de contraste sont imprévisibles. Cet article examine l'utilisation des agents de contraste iodés et à base de gadolinium en imagerie médicale. Il explore la présentation clinique de leurs réactions, les facteurs de risque, les précautions préalables à leur administration et les options de traitement en cas de réaction. En mettant en lumière ces aspects essentiels, l'article vise à informer les professionnels de la santé sur la gestion sécuritaire et efficace de ces agents lors des procédures d'imagerie. L'efficacité des différents protocoles de prémédication proposés dans la littérature n'est pas établie. En particulier, la prémédication ne prévient pas les réactions allergiques graves.
Subject(s)
Contrast Media , Gadolinium , Humans , Contrast Media/adverse effects , Contrast Media/administration & dosage , Gadolinium/administration & dosage , Risk Factors , Drug Hypersensitivity/diagnosis , Diagnostic Imaging/methodsABSTRACT
BACKGROUND: To evaluate and compare the diagnostic power of [18F]FLT-PET with ceMRI in patients with brain tumours or other focal lesions. METHODS: 121 patients with suspected brain tumour or those after brain tumour surgery were enroled in this retrospective study (61 females, 60 males, mean age 37.3 years, range 1-80 years). All patients underwent [18F]FLT-PET/MRI with gadolinium contrast agent application. In 118 of these patients, a final diagnosis was made, verified by histopathology or by follow-up. Agreement between ceMRI and [18F]FLT-PET of the whole study group was established. Further, sensitivity and specificity of ceMRI and [18F]FLT-PET were calculated for differentiation of high-grade vs. low-grade tumours, high-grade vs. low-grade tumours together with non-tumour lesions and for differentiation of high-grade tumours from all other verified lesions. RESULTS: [18F]FLT-PET and ceMRI findings were concordant in 119 cases (98%). On closer analysis of a subset of 64 patients with verified gliomas, the sensitivity and specificity of both PET and ceMRI were identical (90% and 84%, respectively) for differentiating low-grade from high-grade tumours, if the contrast enhancement and [18F]FLT uptake were considered as hallmarks of high-grade tumour. For differentiation of high-grade tumours from low-grade tumours and lesions of nontumorous aetiology (e.g., inflammatory lesions or post-therapeutic changes) in a subgroup of 93 patients by visual evaluation, the sensitivity of both PET and ceMRI was 90%, whereas the specificity of PET was slightly higher (61%) compared to ceMRI (57%). By receiver operating characteristic analysis, the sensitivity and specificity were 82% and 74%, respectively, when the threshold of SUVmax in the tumour was set to 0.9 g/ml. CONCLUSION: We demonstrated a generally very high correlation of [18F]FLT accumulation with contrast enhancement visible on ceMRI and a comparable diagnostic yield in both modalities for differentiating high-grade tumours from low-grade tumours and lesions of other aetiology.
Subject(s)
Brain Neoplasms , Gadolinium , Magnetic Resonance Imaging , Positron-Emission Tomography , Humans , Male , Female , Middle Aged , Aged , Adult , Brain Neoplasms/diagnostic imaging , Brain Neoplasms/pathology , Brain Neoplasms/metabolism , Aged, 80 and over , Positron-Emission Tomography/methods , Magnetic Resonance Imaging/methods , Adolescent , Child, Preschool , Child , Young Adult , Retrospective Studies , Gadolinium/pharmacokinetics , Infant , Contrast Media , Radiopharmaceuticals , Multimodal Imaging/methods , Dideoxynucleosides , Sensitivity and SpecificityABSTRACT
BACKGROUND: Gadolinium Leakage into Ocular Structures (GLOS) is common following acute cerebrovascular events. The objective of this study was to investigate the occurrence of GLOS in an acute traumatic brain injury (TBI) cohort without acute cerebrovascular injury and to explore associated factors. METHODS: Enrolled acute TBI patients had a baseline MRI ≤48 h of injury (TP1) and follow-up MRI ≤72 h after baseline (TP2). Vitreous chamber enhancement and signal intensity ratios (SIRs) were calculated using pre- and post-contrast Fluid Attenuated Inversion Recovery (FLAIR). White matter hyperintensities (WMHs) were assessed using the Fazekas scale. RESULTS: Of the 128 TBI patients included, median age was 47 years, 70% male, and 66% presented with Glasgow Coma Scale of 15. No GLOS was detected at TP1 but was present in 23% of patients at TP2. GLOS+ patients were older (68 years [56-76] vs 39 years [27-53], p < 0.001), more likely to report falls as injury mechanism (62% vs 36%, p = 0.006), report history of hypertension (41% vs 19%, p = 0.025), and had a higher burden of WMHs (59% vs 14% with a total Fazekas ≥2, p < 0.001). Quantitative SIRs confirmed qualitative assessments: GLOS+ patients had higher SIRs at TP2 (0.43 vs 0.22, p < 0.001). Age (OR 3.28, 95%CI [1.88-5.71], p < 0.001) and prior TBI history (OR 4.99, 95%CI [1.46-17.06], p = 0.010) were independent predictors of GLOS. When age was removed, total Fazekas score (OR 2.53, 95%CI [1.60-4.00], p < 0.001) was an independent predictor of GLOS. CONCLUSIONS: GLOS is primarily associated with age and may serve as another imaging marker of chronic vascular disease.
Subject(s)
Brain Injuries, Traumatic , Gadolinium , Magnetic Resonance Imaging , Humans , Male , Middle Aged , Female , Brain Injuries, Traumatic/diagnostic imaging , Brain Injuries, Traumatic/complications , Aged , Adult , Magnetic Resonance Imaging/methods , Contrast Media/adverse effects , Age Factors , Cohort StudiesABSTRACT
INTRODUCTION: Malignant ventricular arrhythmia (VA) and sudden cardiac death (SCD) have been reported in patients with mitral valve prolapse (MVP); however, effective risk stratification methods are still lacking. Myocardial fibrosis is thought to play an important role in the development of VA; however, observational studies have produced contradictory findings regarding the relationship between VA and late gadolinium enhancement (LGE) in MVP patients. The aim of this meta-analysis and systematic review of observational studies was to investigate the association between left ventricular LGE and VA in patients with MVP. METHODS: We searched the PubMed, Embase, and Web of Science databases from 1993 to 2023 to identify case-control, cross-sectional, and cohort studies that compared the incidence of VA in patients with MVP who had left ventricular LGE and those without left ventricular LGE. RESULTS: A total of 1464 subjects with MVP from 12 observational studies met the eligibility criteria. Among them, VA episodes were reported in 221 individuals (15.1%). Meta-analysis demonstrated that the presence of left ventricular LGE was significantly associated with an increased risk of VA (pooled risk ratio 2.96, 95% CI: 2.26-3.88, p for heterogeneity = 0.07, I2 = 40%). However, a meta-regression analysis of the prevalence of mitral regurgitation (MR) showed that the severity of MR did not significantly affect the association between the occurrence of LGE and VA (p = 0.079). CONCLUSION: The detection of LGE could be helpful for stratifying the risk of VA in patients with MVP.
Subject(s)
Contrast Media , Gadolinium , Magnetic Resonance Imaging, Cine , Mitral Valve Prolapse , Humans , Mitral Valve Prolapse/complications , Mitral Valve Prolapse/diagnosis , Mitral Valve Prolapse/epidemiology , Mitral Valve Prolapse/physiopathology , Gadolinium/pharmacology , Magnetic Resonance Imaging, Cine/methods , Arrhythmias, Cardiac/diagnosis , Arrhythmias, Cardiac/etiology , Arrhythmias, Cardiac/epidemiology , Risk Factors , Risk Assessment/methodsABSTRACT
The aim of this study is to assess the effectiveness of conventional and two additional functional markers derived from standard cardiac magnetic resonance (CMR) images in detecting the occurrence of late gadolinium enhancement (LGE) in patients with secondary cardiac amyloidosis (CA) related to multiple myeloma (MM). This study retrospectively included 32 patients with preserved ejection fraction (EF) who had MM-CA diagnosed consecutively. Conventional left ventricular (LV) function markers and two additional functional markers, namely myocardial contraction fraction (MCF) and LV long-axis strain (LAS), were obtained using commercial cardiac post-processing software. Logistic regression analyses and receiver operating characteristic (ROC) analysis were performed to evaluate the predictive performances. (1) There were no notable distinctions in clinical features between the LGE+ and LGE- groups, with the exception of a reduced systolic blood pressure in the former (105.60 ± 18.85 mmHg vs. 124.50 ± 20.95 mmHg, P = 0.022). (2) Patients with MM-CA presented with intractable heart failure with preserved ejection fraction (HFpEF). The LVEF in the LGE+ group exhibited a greater reduction (54.27%, IQR 51.59-58.39%) in comparison to the LGE- group (P < 0.05). And MM-CA patients with LGE+ had significantly higher LVMI (90.15 ± 23.69 g/m2), lower MCF (47.39%, IQR 34.28-54.90%), and the LV LAS were more severely damaged (- 9.94 ± 3.42%) than patients with LGE- (all P values < 0.05). (3) The study found that MCF exhibited a significant independent association with LGE, as indicated by an odds ratio of 0.89 (P < 0.05). The cut-off value for MCF was determined to be 64.25% with a 95% confidence interval ranging from 0.758 to 0.983. The sensitivity and specificity of this association were calculated to be 95% and 83%, respectively. MCF is a simple reproducible predict marker of LGE in MM-CA patients. It is a potentially CMR-based method that promise to reduce scan times and costs, and boost the accessibility of CMR.
Subject(s)
Amyloidosis , Gadolinium , Multiple Myeloma , Myocardial Contraction , Humans , Multiple Myeloma/diagnostic imaging , Multiple Myeloma/complications , Multiple Myeloma/pathology , Female , Male , Aged , Middle Aged , Amyloidosis/diagnostic imaging , Amyloidosis/physiopathology , Amyloidosis/pathology , Retrospective Studies , Stroke Volume , Ventricular Function, Left , Contrast Media , Magnetic Resonance Imaging/methods , Cardiomyopathies/diagnostic imaging , Cardiomyopathies/physiopathology , Cardiomyopathies/etiology , ROC Curve , Magnetic Resonance Imaging, Cine/methodsABSTRACT
In this study, we developed new gadolinium-graphene quantum dot nanoparticles (Gd-GQDs) as a theranostic platform for magnetic resonance imaging and improved the efficiency of radiotherapy in HPV-positive oropharyngeal cancer. Based on cell toxicity results, Gd-GQD NPs were nontoxic for both cancer and normal cell lines up to 25 µg/ml. These NPs enhance the cytotoxic effect of radiation only on cancer cells but not on normal cells. The flow cytometry analysis indicated that cell death mainly occurred in the late phase of apoptosis. The immunocytochemical analysis was used to evaluate apoptosis pathway proteins. The Bcl-2 and p53 protein levels did not differ statistically significantly between radiation alone group and those that received irradiation in combination with NPs. In contrast, the combination group exhibited a significant increase in Bax protein expression, suggesting that cells could undergo apoptosis independent of the p53 pathway. Magnetic resonance (MR) imaging showed that Gd-GQD NPs, when used at low concentrations, enhanced T1-weighted signal intensity resulting from T1 shortening effects. At higher concentrations, the T2 shortening effect became predominant and was able to decrease the signal intensity. Gd-GQD appears to offer a novel approach for enhancing the effectiveness of radiation treatment and facilitating MR imaging for monitoring HPV-positive tumors.
Subject(s)
Gadolinium , Magnetic Resonance Imaging , Oropharyngeal Neoplasms , Papillomavirus Infections , Quantum Dots , Humans , Oropharyngeal Neoplasms/virology , Oropharyngeal Neoplasms/pathology , Oropharyngeal Neoplasms/therapy , Oropharyngeal Neoplasms/radiotherapy , Papillomavirus Infections/complications , Papillomavirus Infections/virology , Magnetic Resonance Imaging/methods , Apoptosis/drug effects , Theranostic Nanomedicine/methods , Cell Line, TumorABSTRACT
NMR spectroscopy is an important tool for the measurement of the electrostatic properties of biomolecules. To this point, paramagnetic relaxation enhancements (PREs) of 1H nuclei arising from nitroxide cosolutes in biomolecular solutions have been used to measure effective near-surface electrostatic potentials (ÏENS) of proteins and nucleic acids. Here, we present a gadolinium (Gd)-based NMR method, exploiting Gd chelates with different net charges, for measuring ÏENS values and demonstrate its utility through applications to a number of biomolecular systems. The use of Gd-based cosolutes offers several advantages over nitroxides for ÏENS measurements. First, unlike nitroxide compounds, Gd chelates enable electrostatic potential measurements on oxidation-sensitive proteins that require reducing agents. Second, the large electron spin quantum number of Gd (7/2) results in notably larger PREs for Gd chelates when used at the same concentrations as nitroxide radicals. Thus, it is possible to measure ÏENS values exclusively from + and - charged compounds even for highly charged biomolecules, avoiding the use of neutral cosolutes that, as we further establish here, limits the accuracy of the measured electrostatic potentials. In addition, the smaller concentrations of cosolutes required minimize potential binding to sites on macromolecules. Fourth, the closer proximity of the paramagnetic center and charged groups within Gd chelates, in comparison to the corresponding nitroxide compounds, enables more accurate predictions of ÏENS potentials for cross-validation of the experimental results. The Gd-based method described here, thus, broadens the applicability of studies of biomolecular electrostatics using solution NMR spectroscopy.
Subject(s)
Gadolinium , Static Electricity , Gadolinium/chemistry , Proteins/chemistry , Surface Properties , Nuclear Magnetic Resonance, Biomolecular , Chelating Agents/chemistry , Magnetic Resonance Spectroscopy/methodsABSTRACT
This study presents a pioneering synthesis of a direct Z-scheme Y2TmSbO7/GdYBiNbO7 heterojunction photocatalyst (YGHP) using an ultrasound-assisted hydrothermal synthesis technique. Additionally, novel photocatalytic nanomaterials, namely Y2TmSbO7 and GdYBiNbO7, were fabricated via the hydrothermal fabrication technique. A comprehensive range of characterization techniques, including X-ray diffractometry, Fourier-transform infrared spectroscopy, Raman spectroscopy, UV-visible spectrophotometry, X-ray photoelectron spectroscopy, transmission electron microscopy, X-ray energy-dispersive spectroscopy, fluorescence spectroscopy, photocurrent testing, electrochemical impedance spectroscopy, ultraviolet photoelectron spectroscopy, and electron paramagnetic resonance, was employed to thoroughly investigate the morphological features, composition, chemical, optical, and photoelectric properties of the fabricated samples. The photocatalytic performance of YGHP was assessed in the degradation of the pesticide acetochlor (AC) and the mineralization of total organic carbon (TOC) under visible light exposure, demonstrating eximious removal efficiencies. Specifically, AC and TOC exhibited removal rates of 99.75% and 97.90%, respectively. Comparative analysis revealed that YGHP showcased significantly higher removal efficiencies for AC compared to the Y2TmSbO7, GdYBiNbO7, or N-doped TiO2 photocatalyst, with removal rates being 1.12 times, 1.21 times, or 3.07 times higher, respectively. Similarly, YGHP demonstrated substantially higher removal efficiencies for TOC than the aforementioned photocatalysts, with removal rates 1.15 times, 1.28 times, or 3.51 times higher, respectively. These improvements could be attributed to the Z-scheme charge transfer configuration, which preserved the preferable redox capacities of Y2TmSbO7 and GdYBiNbO7. Furthermore, the stability and durability of YGHP were confirmed, affirming its potential for practical applications. Trapping experiments and electron spin resonance analyses identified active species generated by YGHP, namely â¢OH, â¢O2-, and h+, allowing for comprehensive analysis of the degradation mechanisms and pathways of AC. Overall, this investigation advances the development of efficient Z-scheme heterostructural materials and provides valuable insights into formulating sustainable remediation strategies for combatting AC contamination.
Subject(s)
Light , Toluidines , Catalysis , Toluidines/chemistry , Photolysis , Water Pollutants, Chemical/chemistry , Photochemical Processes , Photoelectron Spectroscopy , Gadolinium/chemistryABSTRACT
A referencing strategy based on the element P is presented to compensate for cryosectioning tissue artifacts in laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) data. The study examines how the gadolinium-based contrast agent Gadofosveset is distributed in murine cancer tissue, and illustrates how referenced images can compensate for tissue artifacts like folds, overlaps, and density variations. Compared to non-referenced images that provide information on the absolute distribution of the analyte, referenced images allow for the representation of the analyte distribution relative to the amount of material introduced into the instrument, which in this case is correlated to the P signal. Tissue artifacts were corrected in referenced images for both Gadofosveset and endogenous elements, such as Fe and Zn. Additionally, the referencing approach provides valuable information on the Gd uptake relative to the tissue density in necrotic compared to vital tumor areas, which is not obtained from in vivo magnetic resonance imaging (MRI) data. However, validation of in vivo MRI and ex vivo LA-ICP-MS methods was possible by establishing a mean ratio of necrotic to vital tumor areas in the T1-weighted image post Gadofosveset injection and the non-referenced LA-ICP-MS image of Gd. In summary, P-based correction of LA-ICP-MS imaging data allows for a more accurate spatial representation of certain elements, including endogenous and exogenous elements such as injected contrast agents.
Subject(s)
Artifacts , Gadolinium , Mass Spectrometry , Animals , Mice , Mass Spectrometry/methods , Gadolinium/chemistry , Laser Therapy/methods , Contrast Media , Magnetic Resonance Imaging/methods , Neoplasms/diagnostic imaging , Neoplasms/pathology , Female , Organometallic Compounds/chemistryABSTRACT
Late gadolinium enhancement (LGE) in cardiovascular magnetic resonance imaging (CMR) prevents left ventricular reverse remodeling (LVRR), resulting in a poor prognosis. However, the prognosis of patients who have LGE and achieve LVRR and patients who do not have LGE and do not achieve LVRR remains unknown. This study aimed to answer this question by sorting patients with heart failure based on the presence of LGE and LVRR and comparing their prognoses. Another aim was to identify useful factors for predicting LVRR.All patients were followed-up for 24 months. LVRR was defined as a ≥ 10% increase at the last follow-up at 12 ± 6 months from baseline, on echocardiography. The primary endpoint was a composite of cardiovascular death and hospitalization due to worsening heart failure within 18 ± 6 months. Baseline data and data from each outpatient visit were collected and analyzed. We enrolled 80 consecutive patients with heart failure and reduced left ventricular ejection fraction (< 50%) who underwent CMR.LGE was positive in 40 patients (50.0%) and LVRR was observed in 50 patients (63%). The incidence of the primary endpoint was significantly lower in the group that achieved LVRR, regardless of LGE status (LGE-positive group, P = 0.01; LGE-negative group, P = 0.02). In the multivariate analysis, the percentage change in NT-pro BNP levels at 3 months, NT-pro BNP levels at 6 months, and age were independent predictors of LVRR.LGE-positive patients may have a better prognosis if they achieve LVRR. Serial NT-pro BNP testing may be a valuable predictor of LVRR.
Subject(s)
Contrast Media , Gadolinium , Heart Failure , Ventricular Remodeling , Humans , Male , Female , Middle Aged , Prognosis , Heart Failure/physiopathology , Aged , Magnetic Resonance Imaging, Cine/methods , Stroke Volume/physiology , Echocardiography/methods , Natriuretic Peptide, Brain/blood , Follow-Up StudiesABSTRACT
C-X-C motif chemokine receptor 4 (CXCR4) is a promising therapeutic target of breast cancer because it is overexpressed on cell surface of all molecular subtypes of breast cancer including triplenegative breast cancer (TNBC). Herein, CXCR4 antagonistic peptide-NaGdF4 nanodot conjugates (termed as anti-CXCR4-NaGdF4 NDs) have been constructed for magnetic resonance imaging (MRI)-guided biotherapy of TNBC through conjugation of the C-X-C Motif Chemokine 12 (CXCL12)-derived cyclic peptide with tryptone coated NaGdF4 nanodots (5 ± 0.5 nm in diameter, termed as Try-NaGdF4 NDs). The as-prepared anti-CXCR4-NaGdF4 NDs exhibits high longitudinal relaxivity (r1) value (21.87 mM-1S-1), reasonable biocompatibility and good tumor accumulation ability. The features of anti-CXCR4-NaGdF4 NDs improve the tumor-MRI sensitivity and facilitate tumor biotherapy after injection in mouse-bearing MDA-MB-231 tumor model in vivo. MRI-guided biotherapy using anti-CXCR4-NaGdF4 NDs enables to suppress 46% tumor growth. In addition, about 47% injection dose of anti-CXCR4-NaGdF4 NDs is found in the mouse urine at 24 h post-injection. These findings demonstrate that anti-CXCR4-NaGdF4 NDs enable to be used as renal clearable nanomedicine for biotherapy and MRI of breast cancer.
Subject(s)
Breast Neoplasms , Magnetic Resonance Imaging , Receptors, CXCR4 , Receptors, CXCR4/metabolism , Animals , Female , Magnetic Resonance Imaging/methods , Humans , Mice , Breast Neoplasms/diagnostic imaging , Breast Neoplasms/therapy , Breast Neoplasms/pathology , Breast Neoplasms/drug therapy , Cell Line, Tumor , Gadolinium/chemistry , Chemokine CXCL12/metabolism , Mice, Nude , Mice, Inbred BALB C , Nanoparticles/chemistry , Peptides, Cyclic/chemistry , Peptides, Cyclic/pharmacology , Xenograft Model Antitumor Assays , Peptides/chemistryABSTRACT
OBJECTIVE: To describe the use of intermittent hemodialysis (IHD) to remove gadolinium (28.1 mg/kg dose) in a dog with severe kidney disease. CASE SUMMARY: A 12-year-old neutered female Yorkshire Terrier presented with severe acute-on-chronic kidney injury and concurrent neurological signs. The dog received extracorporeal therapy as part of management. Uremia improved after hemodialysis, but central nervous system signs persisted; therefore, a contrast-enhanced magnetic resonance imaging was performed, immediately followed by IHD. Two IHD treatments with a low-flux dialyzer were performed 1.5 and 25.75 hours after administration of gadolinium, with almost complete removal of gadolinium. More than 96% of gadolinium was removed with a single treatment. NEW OR UNIQUE INFORMATION PROVIDED: Extracorporeal therapy is effective at removing gadolinium-based chelated contrast agents and could be considered if magnetic resonance imaging is indicated in a patient with substantial kidney impairment. Alternatively, newer contrast agents that have been deemed safer in this patient population could be used.
Subject(s)
Contrast Media , Dog Diseases , Gadolinium , Renal Dialysis , Dogs , Animals , Female , Dog Diseases/therapy , Dog Diseases/diagnostic imaging , Renal Dialysis/veterinary , Magnetic Resonance Imaging/veterinary , Acute Kidney Injury/veterinary , Acute Kidney Injury/therapy , Renal Insufficiency, Chronic/veterinary , Renal Insufficiency, Chronic/therapy , Renal Insufficiency, Chronic/complicationsABSTRACT
BACKGROUND AND PURPOSE: After repeat administration of gadolinium-based contrast agents (GBCAs), the association between gadolinium retention in the central and peripheral nervous systems and the main manifestations of myelopathy and progressive neurologic symptoms remains unclear. We investigated the effects of the repeat administration of GBCAs on gadolinium retention in the central and peripheral nervous systems and the sensory, cognitive, and athletic implications. MATERIALS AND METHODS: Forty-eight male Wistar rats (6 weeks of age) were randomly divided into 4 experimental groups (12 rats in each group): the gadodiamide group (linear and nonionic GBCAs), the gadopentetate dimeglumine group (linear and ionic GBCAs), the gadoterate meglumine group (macrocyclic and ionic GBCAs), and the control group (0.9% saline solution). The brains of the rats were scanned using 9.4T MRI. Sensory behavioral tests were performed to assess the effect of GBCAs on pain sensitivity function. Gadolinium deposition in the brain, spinal cord, and peripheral nerves was determined by inductively coupled plasma mass-spectrometry. Transmission electron microscopy was used to observe the microscopic distribution of gadolinium after deposition in the spinal cord. The histopathologic features in the spinal cord were analyzed by H&E staining, Nissl staining, glial fibrillary acidic protein staining, and neuron-specific enolase staining after administration of GBCAs. RESULTS: All GBCAs resulted in gadolinium deposition in the central and peripheral nerve tissues, with the highest deposition in the sciatic nerve tissue (mean, 62.86 [SD, 12.56] nmol/g). Decreased muscle power, impairment of spatial cognitive function power, and pain hypersensitivity to thermal and mechanical stimuli were observed after exposure to gadodiamide. At the spinal cord, transmission electron microscopy found that the region of gadolinium depositions had a spheric structure similar to "sea urchins" and was mainly located near the vascular basement membrane. CONCLUSIONS: Multiple injections of GBCAs caused gadolinium deposition in the brain, spinal cord, and peripheral nerves, especially in the spinal cords of the gadodiamide group. Gadodiamide led to pain hypersensitivity and decreased muscle power and cognitive ability. For the patients who are hypersensitive to pain and need multiple MRI examinations, we recommend using macrocyclic GBCAs and the lowest dose possible.
Subject(s)
Contrast Media , Gadolinium , Rats, Wistar , Animals , Contrast Media/pharmacokinetics , Male , Rats , Gadolinium/pharmacokinetics , Magnetic Resonance Imaging/methods , Cognition/drug effects , Gadolinium DTPA/pharmacokinetics , Gadolinium DTPA/administration & dosage , Peripheral Nervous System/drug effects , Peripheral Nervous System/diagnostic imaging , Spinal Cord/diagnostic imaging , Spinal Cord/metabolism , Spinal Cord/drug effects , Central Nervous System/diagnostic imaging , Central Nervous System/drug effects , Central Nervous System/metabolism , Brain/diagnostic imaging , Brain/metabolism , Brain/drug effectsABSTRACT
Importance: Understanding the association between clinically defined relapses and radiological activity in multiple sclerosis (MS) is essential for patient treatment and therapeutic development. Objective: To investigate clinical events identified as relapses but not associated with new T2 lesions or gadolinium-enhanced T1 lesions on brain and spinal cord magnetic resonance imaging (MRI). Design, Setting, and Participants: This multicenter observational cohort study was conducted between January 2015 and June 2023. Data were extracted on June 8, 2023, from the French MS registry. All clinical events reported as relapses in patients with relapsing-remitting MS were included if brain and spinal cord MRI was performed within 12 and 24 months before the event, respectively, and 50 days thereafter with gadolinium injection. Exposures: Events were classified as relapses with active MRI (RAM) if a new T2 lesion or gadolinium-enhanced T1 lesion appeared on brain or spinal cord MRI or as acute clinical events with stable MRI (ACES) otherwise. Main Outcomes and Measures: Factors associated with ACES were investigated; patients with ACES and RAM were compared regarding Expanded Disability Status Scale (EDSS) course, relapse rate, confirmed disability accrual (CDA), relapse-associated worsening (RAW), progression independent of relapse activity (PIRA), and transition to secondary progressive (SP) MS, and ACES and RAM rates under each disease-modifying therapy (DMT) were estimated. Results: Among 31â¯885 clinical events, 637 in 608 patients (493 [77.4%] female; mean [SD] age, 35.8 [10.7] years) were included. ACES accounted for 166 (26.1%) events and were more likely in patients receiving highly effective DMTs, those with longer disease duration (odds ratio [OR], 1.04; 95% CI, 1.01-1.07), or those presenting with fatigue (OR, 2.14; 95% CI, 1.15-3.96). ACES were associated with significant EDSS score increases, lower than those found for RAM. Before the index event, patients with ACES experienced significantly higher rates of relapse (relative rate [RR], 1.21; 95% CI, 1.01-1.46), CDA (hazard ratio [HR], 1.54; 95% CI, 1.13-2.11), and RAW (HR, 1.72; 95% CI, 1.20-2.45). Patients with ACES were at significantly greater risk of SP transition (HR, 2.58; 95% CI, 1.02-6.51). Although RAM rate decreased with DMTs according to their expected efficacy, ACES rate was stable across DMTs. Conclusions and Relevance: The findings in this study introduce the concept of ACES in MS, which accounted for one-fourth of clinical events identified as relapses.