Capability Of Magnetic Resonance Imaging Research Articles

Metal Nanoparticles for Simultaneous Use in AC Magnetic Field Hyperthermia and Magnetic Resonance Imaging.

Magnetic nanoparticles (MNPs) are produced for both diagnosis and treatment due to their simultaneous availability in magnetic resonance imaging (MRI) and magnetic hyperthermia (MHT). Extensive investigations focus on developing MNPs for individual MHT or MRI applications, but the development of MNPs for theragnostic applications has received very little attention. In this study, through efficient examination of synthesis conditions such as metal precursors, reaction parameters, and solvent choices, we aimed to optimize MNP production for effective utilization for MHT and MRI simultaneously. MNPs were synthesized by thermal decomposition under 17 different conditions and deeply characterized by transmission electron microscopy (TEM), x-ray diffraction (XRD), and x-ray photoelectron spectroscopy (XPS). The heating efficiency of MNPs under an alternating current (AC) magnetic field was quantified, while MRI performance was evaluated through agar phantom experiments. Our findings highlight the crucial role of benzyl ether in metal ion reduction and size control. Metal-doped iron oxide MNPs displayed promise for MHT, whereas Mn-doped iron oxide MNPs exhibited enhanced MRI capabilities. Consequently, five engineered MNPs were considered potential candidates for further studies, demonstrating their dual ability in MRI and MHT.

Cu/Gd co-doped hydroxyapatite/poly lactic-co-glycolic acid composites enhance MRI imaging and bone defect regeneration.

Background: The hydroxyapatite (HA)/poly(lactide-co-glycolide) acid (PLGA) composite material is a widely used orthopedic implant due to its excellent biocompatibility and plasticity. Recent advancements in cation doping have expanded its potential biological applications. However, conventional HA/PLGA composites are not visible under X-rays post-implantation and have limited osteogenic induction capabilities. Copper (Cu) is known to regulate osteoblast proliferation and differentiation, while gadolinium (Gd) can significantly enhance the magnetic resonance imaging (MRI) capabilities of materials. Methods: This study aimed to investigate whether incorporating Cu and Gd into an HA/PLGA composite could enhance the osteogenic properties, in vivo bone defect repair, and MRI characteristics. We prepared a Cu/Gd@HA/PLGA composite and assessed its performance. Results: Material characterization confirmed that Cu/Gd@HA retained the morphology and crystal structure of HA. The Cu/Gd@HA/PLGA composite exhibited excellent nuclear magnetic imaging capabilities, porosity, and hydrophilicity, which are conducive to cell adhesion and implant detection. In vitro experiments demonstrated that the Cu/Gd@HA/PLGA composite enhanced the proliferation, differentiation, and adhesion of MC3T3-E1 cells, and upregulated COL-1 and BMP-2 expression at both gene and protein levels. In vivo studies showed that the Cu/Gd@HA/PLGA composite maintained strong T1-weighted MRI signals and significantly improved the bone defect healing rate in rats. Conclusion: These findings indicate that the Cu/Gd@HA/PLGA composites significantly enhance T1-weighted MRI capabilities, promote osteoblast proliferation and differentiation in vitro, and accelerate bone defect healing in vivo.

Prevalence of iron overload in patients with chronic kidney disease on peritoneal dialysis: A scoping review.

Chronic kidney disease (CKD) patients undergoing peritoneal dialysis (PD) are susceptible to complications, including iron overload, which can significantly impact their prognosis and overall health. This scoping review aimed to study the prevalence and implications of iron overload in CKD patients undergoing PD. A comprehensive search was conducted across five databases, leading to the selection of 18 papers for in-depth analysis. These studies collectively involved 381 PD patients, 60.3% were males. No consensus was reached regarding the exact diagnostic cutoff for iron overload. The investigations revealed four main aspects: (1) Seven papers identified various factors contributing to iron overload, emphasizing the role of different iron supplements and magnetic resonance imaging's capability to diagnose iron accumulation in organs; (2) Iron overload in young patients was found to hinder growth; (3) Six studies highlighted the adverse effects of iron overload, with cardiac issues being the most significant; (4) Three studies demonstrated the efficacy of iron-chelating agents, Deferoxamine and Deferasirox, in treating iron overload patients undergoing PD. Overall, the estimated prevalence of liver iron overload in CKD patients on PD ranges from approximately 10% to 28.6%, which is far lower than the prevalence of 75% elegantly shown in HD patients. While iron overload was a significant concern for CKD patients undergoing PD in the past, it is less common in the current era due to advancements in treatments, such as erythropoiesis-stimulating agents. Treatment with specific chelation agents has proven beneficial, but there is also a risk of adverse effects, necessitating meticulous monitoring and timely intervention.

Temporal Optimization in the Synthesis of Multifunctional Nano Agents for Enhanced MRI Contrast, Hyperthermia Therapy, and ROS Generation.

Advanced methodologies, such as hyperthermia and modulation of reactive oxygen species (ROS), exhibit considerable promise in the therapeutic landscape of cancer. These strategies offer a targeted paradigm for combating malignant cells while mitigating damage to healthy tissue. Noteworthy among these approaches is the utilization of superparamagnetic iron oxide nanoparticles, which are renowned for their ability to enhance both hyperthermia and ROS generation specifically within tumor microenvironments. The objective of this investigation is to scrutinize the relationship between the reaction duration and the characteristics of carbon-doped silica core-shell iron oxide nanoparticles (CSIONPs). Specifically, we focus on CSIONP-12, CSIONP-24, and CSIONP-36, synthesized by using varying reaction periods. Through a comprehensive analysis, we primarily evaluate the impact of these formulations on T1 and T2 magnetic resonance imaging (MRI), aiming to elucidate their mechanisms and therapeutic potential in promoting hyperthermia and ROS-mediated cancer therapy. CSIONP-24 emerges as a compelling candidate due to its dual influence on magnetic hyperthermia and ROS generation, suggesting its promise in enhancing cancer treatment outcomes. Furthermore, the findings underscore the exceptional T1-T2 MRI capabilities of this technology, underscoring its versatility and efficacy in the nuanced realm of cancer theranostic.

Synthetic MRI and MR Fingerprinting-Derived Relaxometry of Antenatal Human Brainstem Myelination: A Postmortem-Based Quantitative Imaging Study.

The radiologic evaluation of ongoing myelination is currently limited prenatally. Novel quantitative MR imaging modalities provide relaxometric properties that are linked to myelinogenesis. In this retrospective postmortem imaging study, the capability of Synthetic MR imaging and MR fingerprinting-derived relaxometry for tracking fetal myelin development was investigated. Moreover, the consistency of results for both MR approaches was analyzed. In 26 cases, quantitative postmortem fetal brain MR data were available (gestational age range, 15 + 1 to 32 + 1; female/male ratio, 14/12). Relaxometric measurements (T1-/T2-relexation times) were determined in the medulla oblongata and the midbrain using Synthetic MR imaging/MR fingerprinting-specific postprocessing procedures (Synthetic MR imaging and MR Robust Quantitative Tool for MR fingerprinting). The Pearson correlations were applied to detect relationships between T1-relaxation times/T2-relaxation times metrics and gestational age at MR imaging. Intraclass correlation coefficients were calculated to assess the consistency of the results provided by both modalities. Both modalities provided quantitative data that revealed negative correlations with gestational age at MR imaging: Synthetic MR imaging-derived relaxation times (medulla oblongata [r = -0.459; P = .021]; midbrain [r = -0.413; P = .040]), T2-relaxation times (medulla oblongata [r = -0.625; P < .001]; midbrain [r = -0.571; P = .003]), and MR fingerprinting-derived T1-relaxation times (medulla oblongata [r = -0.433; P = .035]; midbrain [r = -0.386; P = .062]), and T2-relaxation times (medulla oblongata [r =-0.883; P < .001]; midbrain [r = -0.890; P < .001]).The intraclass correlation coefficient analysis for result consistency between both MR approaches ranged between 0.661 (95% CI, 0.351-0.841) (T2-relaxation times: medulla oblongata) and 0.920 (95% CI, 0.82-0.965) (T1-relaxation times: midbrain). There is a good-to-excellent consistency between postmortem Synthetic MR imaging and MR fingerprinting myelin quantifications in fetal brains older than 15 + 1 gestational age. The strong correlations between quantitative myelin metrics and gestational age indicate the potential of quantitative MR imaging to identify delayed or abnormal states of myelination at prenatal stages of cerebral development.

Ti3C2Tx MXene quantum dots coated hollow manganese dioxide nanoparticles for tumor combination therapy and magnetic resonance imaging

Chemodynamic therapy (CDT) is a new cancer treatment that uses low-valence transition metal ions to catalyze intracellular Fenton/Fenton-like reactions, producing hydroxyl radicals (•OH) to eliminate cancer cells. However, achieving satisfactory therapeutic outcomes with CDT alone can be challenging. In this work, we reported an anticancer drug delivery DOX@HMDN-TQDs@PEI-PEG (DMTP) based on hollow mesoporous manganese dioxide nanoparticle (HMDN), which has the potential to improve cancer therapy by combining synergistic therapeutic and tumor magnetic resonance imaging (MRI) capability. After loading the anticancer drug doxorubicin hydrochloride (DOX), the pores of HMDN were sealed with polyethyleneimine (PEI) modified Ti3C2Tx MXene quantum dots (TQDs) and finally modified with polyethylene glycol (PEG) to obtain the final system. HMDN depletes glutathione (GSH), which is harmful to CDT, in cancer cells, and generates Mn2+ that can be used for both CDT and MRI. TQDs can also be used for highly effective photothermal therapy (PTT) that enhances CDT. The combination of DOX with chemotherapy can significantly inhibit tumor growth. In addition, DMTP combines the capability of tumor MRI as Mn2+ is also a T1-weighted contrast agent. This multifunctional delivery system provides new ideas for research related to tumor diagnosis and treatment.

Structural Defect-Enabled Magnetic Neutrality Nanoprobes for Ultra-High-Field Magnetic Resonance Imaging of Isolated Tumor Cells in Vivo.

The identification of metastasis "seeds," isolated tumor cells (ITCs), is of paramount importance for the prognosis and tailored treatment of metastatic diseases. The conventional approach to clinical ITCs diagnosis through invasive biopsies is encumbered by the inherent risks of overdiagnosis and overtreatment. This underscores the pressing need for noninvasive ITCs detection methods that provide histopathological-level insights. Recent advancements in ultra-high-field (UHF) magnetic resonance imaging (MRI) have ignited hope for the revelation of minute lesions, including the elusive ITCs. Nevertheless, currently available MRI contrast agents are susceptible to magnetization-induced strong T2-decaying effects under UHF conditions, which compromises T1 MRI capability and further impedes the precise imaging of small lesions. Herein, this study reports a structural defect-enabled magnetic neutrality nanoprobe (MNN) distinguished by its paramagnetic properties featuring an exceptionally low magnetic susceptibility through atomic modulation, rendering it almost nonmagnetic. This unique characteristic effectively mitigates T2-decaying effect while concurrently enhancing UHF T1 contrast. Under 9 T MRI, the MNN demonstrates an unprecedentedly low r2/r1 value (≈1.06), enabling noninvasive visualization of ITCs with an exceptional detection threshold of ≈0.16mm. These high-performance MNNs unveil the domain of hitherto undetectable minute lesions, representing a significant advancement in UHF-MRI for diagnostic purposes and fostering comprehensive metastasis research.

MODERN IMAGING TECHNIQUES IN THE ASSESSMENT&#x0D; OF MALIGNANCY IN GLIAL BRAIN TUMORS:&#x0D; LITERATURE REVIEW

Relevance: Gliomas represent a major group of primary central nervous system tumors, accounting for approximately 80% of all&#x0D; malignant brain neoplasms. Recent advances in molecular diagnostics, including the identification of mutations in the isocitrate dehydrogenase(IDH) gene, offer new opportunities to improve the classification of gliomas and to understand the mechanisms of their development. IDH&#x0D; mutations, which are found in a large proportion of gliomas, are associated with a better prognosis and represent an important biomarker&#x0D; for the development of targeted therapeutic strategies. Diagnostic techniques, particularly magnetic resonance imaging (MRI), also play&#x0D; an important role, providing additional ways to assess the morphological and biological characteristics of gliomas, contributing to a more&#x0D; accurate determination of tumor malignancy and molecular profile, which is key to treatment decisions.&#x0D; The purpose: To study the possibilities of magnetic resonance imaging in assessing the degree of malignancy of glial brain tumors.&#x0D; Method: A literature review was performed using the keywords: glioma, IDH mutation, IDH wild-type, MRI, magnetic resonance&#x0D; spectroscopy (MRS), apparent diffusion coefficient (ADC), diffusion-weighted imaging (DWI), diffusion tensor imaging (DTI), diffusion kurtosis&#x0D; image (DKI), Susceptibility Weighted Imaging (SWI) in PubMed, BMC Medicine, and Google Scholar databases. The review includes the results&#x0D; of an analysis of 45 literature reviews on the diagnostic capabilities of molecular diagnostics and MRI to assess the malignancy of gliomas.&#x0D; Results: This review highlights the importance of current approaches to the diagnosis of gliomas, demonstrating that different grades of&#x0D; malignancy and IDH mutation status are associated with unique features on MR imaging, including differences in localization, signal, and&#x0D; enhancement patterns. DTI and DWI extend the ability of MRI to assess tissue microstructure, allowing for more precise tumor characterization.&#x0D; Studies combining MRI morphologic features, ADC and DTI parameters offer a non-invasive approach to glioma prognosis, highlighting the&#x0D; importance of integrated use of imaging modalities to improve diagnosis and therapy.&#x0D; Conclusion: The use of magnetic resonance imaging allows for more accurate morphologic and metabolic characterization of gliomas&#x0D; in assessing the degree of malignancy, allowing physicians to make more accurate prognostic assessments and select the most appropriate&#x0D; treatment strategy.&#x0D; Keywords: Glioma, IDH mutation, wild-type IDH, MRI, magnetic resonance spectroscopy, ADC, DWI, DTI, DKI, SWI

The first experience of using magnetic resonance tomography for lung imaging in children with cystic fibrosis: opportunities and prospects

Cystic fibrosis (CF) is a hereditary disease associated with systemic failure of the exocrine glands. In 95% of the cases, progressive damage to the lung tissue occurs that requires follow-up. The main imaging methods are radiography and computed tomography (CT). Both methods involve ionizing radiation. According to clinical guidelines, a chest X-ray is performed no more than once every 2 years. However, given the high risk of developing inflammatory processes in children with CF, the frequency of radiological examinations may increase significantly. The search for alternative methods without ionizing radiation is in great demand among children with CF. One of these methods is magnetic resonance imaging (MRI).The aim was to explore the capabilities of MRI for imaging lung tissue in children with CF.Methods. The study included 12 patients aged 7 to 18 years with newly diagnosed and previously diagnosed CF. All children underwent CT and MRI of the chest.Results. In all children (100%), chest CT revealed a complex of changes typical of CF: signs of chronic bronchitis, widespread saccular and cylindrical bronchiectasis of various localizations, areas of pulmonary fibrosis, infiltrative changes in the lung tissue. Chest MRI is most effective (100%) in identifying areas of pulmonary fibrosis (thickening of the lung tissue), accumulation of exudate in the lumen of bronchiectasis, and infiltrative changes. In contrast to CT, MRI is less effective in the assessment of bronchitis changes with thickening of the bronchial walls without exudate (83%). A low efficiency of MRI is observed in the visualization of bronchiectasis with a free lumen (without signs of mucostasis).Conclusion. Radiography and computed tomography remain the main methods for lung imaging in children with CF. However, taking into account the absence of ionizing radiation, the development of the method and the emergence of new sequences, chest MRI can be used effectively for follow-up instead of radiography and CT, reducing the radiation dose received.

MRI-guided cell membrane-camouflaged bimetallic coordination nanoplatform for combined tumor phototherapy

Nanotechnology for tumor diagnosis and optical therapy has attracted widespread interest due to its low toxicity and convenience but is severely limited due to uncontrollable tumor targeting. In this work, homologous cancer cell membrane-camouflaged multifunctional hybrid metal coordination nanoparticles (DRu/Gd@CM) were prepared for MRI-guided photodynamic therapy (PDT) and photothermal therapy (PTT) of tumors. Bimetallic coordination nanoparticles are composed of three functional modules: dopamine, Ru(dcbpy)3Cl2 and GdCl3, which are connected through 1,4-Bis[(1H-imidazole-1-yl)methyl]benzene (BIX). Their morphology can be easily controlled by adjusting the ratio of precursors. Optimistically, the intrinsic properties of the precursors, including the photothermal properties of polydopamine (PDA), the magnetic resonance (MR) response of Gd3+, and the singlet oxygen generation of Ru(dcbpy)3Cl2, are well preserved in the hybrid metal nanoparticles. Furthermore, the targeting of homologous cancer cell membranes enables these coordinated nanoparticles to precisely target tumor cells. The MR imaging capabilities and the combination of PDT and PTT were demonstrated in in vitro experiments. In addition, in vivo experiments indicated that the nanoplatform showed excellent tumor accumulation and therapeutic effects on mice with subcutaneous tumors, and could effectively eliminate tumors within 14 days. Therefore, it expanded the new horizon for the preparation of modular nanoplatform and imaging-guided optical therapy of tumors.

Rare-earth-based polymeric nanobubbles as tri-modal imaging contrast agent

Medical imaging plays an important role in providing sufficient guidance for disease diagnosis and treatment. Among them, multimodal contrast agents can combine with a variety of imaging technologies to obtain comprehensive information on the lesion. It is an important development direction of medical imaging for accurate diagnosis of most diseases. In this study, we have designed and prepared a novel nanocomposite (i.e. NaGdF4:Eu@PLGA NBs) by combining sulfur hexafluoride (SF6) loaded polylactic acid-co-glycolic acid (PLGA) nanobubbles (NBs) with NaGdF4:Eu nanoparticles (NPs), which is the first research work on the composite assembly of ultrasound contrast bubbles with rare earth nanomaterials. Results show that NaGdF4:Eu@PLGA NBs with a diameter of appropriately 220 nm had uniform size and good in vitro stability. Combined with PLGA NBs’ superior ultrasound (US) imaging characteristics and NaGdF4:Eu NPs’ excellent magnetic resonance imaging (MRI) and computed tomography (CT) imaging characteristics, NaGdF4:Eu@PLGA NBs have exhibited significant and long-term in vitro US imaging, MRI and CT tri-modal contrast enhancement capability. Taken together, NaGdF4:Eu@PLGA NBs have great potential to be utilized in biomedical applications of US/MRI/CT tri-modal imaging.

From strength to precision: A systematic review exploring the clinical utility of 7-Tesla magnetic resonance imaging in abdominal imaging.

After approval for clinical use in 2017 early investigations of ultra-high-field abdominal magnetic resonance imaging (MRI) have demonstrated the feasibility as well as diagnostic capabilities of liver, kidney, and prostate MRI at 7-Tesla. However, the elevation of the field strength to 7-Tesla not only brought advantages to abdominal MRI but also presented considerable challenges and drawbacks, primarily stemming from heightened artifacts and limitations in Specific Absorption Rate, etc. Furthermore, evidence in the literature is relatively scarce concerning human studies in comparison to phantom/animal studies which necessitates an investigation into the evidence so far in humans and summarizing all relevant evidence. To offer a comprehensive overview of current literature on clinical abdominal 7T MRI that emphasizes current trends, details relevant challenges, and provides a concise set of potential solutions. This systematic review adheres to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. A PubMed search, utilizing Medical Subject Headings terms such as "7-Tesla" and organ-specific terms, was conducted for articles published between January 1, 1985, and July 25, 2023. Eligibility criteria included studies exploring 7T MRI for imaging human abdominal organs, encompassing various study types (in-vivo/ex-vivo, method development, reviews/meta-analyses). Exclusion criteria involved animal studies and those lacking extractable data. Study selection involved initial identification via title/abstract, followed by a full-text review by two researchers, with discrepancies resolved through discussion. Data extraction covered publication details, study design, population, sample size, 7T MRI protocol, image characteristics, endpoints, and conclusions. The systematic review included a total of 21 studies. The distribution of clinical 7T abdominal imaging studies revealed a predominant focus on the prostate (n = 8), followed by the kidney (n = 6) and the hepatobiliary system (n = 5). Studies on these organs, and in the pancreas, demonstrated clear advantages at 7T. However, small bowel studies showed no significant improvements compared to traditional MRI at 1.5T. The majority of studies evaluated originated from Germany (n = 10), followed by the Netherlands (n = 5), the United States (n = 5), Austria (n = 2), the United Kingdom (n = 1), and Italy (n = 1). Further increase of abdominal clinical MRI field strength to 7T demonstrated high imaging potential, yet also limitations mainly due to the inhomogeneous radiofrequency (RF) excitation field relative to lower field strengths. Hence, further optimization of dedicated RF coil elements and pulse sequences are expected to better optimize clinical imaging at high magnetic field strength.

Advancing MRI with magnetic nanoparticles: a comprehensive review of translational research and clinical trials.

The nexus of advanced technology and medical therapeutics has ushered in a transformative epoch in contemporary medicine. Within this arena, Magnetic Resonance Imaging (MRI) emerges as a paramount tool, intertwining the advancements of technology with the art of healing. MRI's pivotal role is evident in its broad applicability, spanning from neurological diseases, soft-tissue and tumour characterization, to many more applications. Though already foundational, aspirations remain to further enhance MRI's capabilities. A significant avenue under exploration is the incorporation of innovative nanotechnological contrast agents. Forefront among these are Superparamagnetic Iron Oxide Nanoparticles (SPIONs), recognized for their adaptability and safety profile. SPION's intrinsic malleability allows them to be tailored for improved biocompatibility, while their functionality is further broadened when equipped with specific targeting molecules. Yet, the path to optimization is not devoid of challenges, from renal clearance concerns to potential side effects stemming from iron overload. This review endeavors to map the intricate journey of SPIONs as MRI contrast agents, offering a chronological perspective of their evolution and deployment. We provide an in-depth current outline of the most representative and impactful pre-clinical and clinical studies centered on the integration of SPIONs in MRI, tracing their trajectory from foundational research to contemporary applications.

Targeted Nanotheransotics: Integration of Preclinical MRI and CT in the Molecular Imaging and Therapy of Advanced Diseases.

The integration of preclinical magnetic resonance imaging (MRI) and computed tomography (CT) methods has significantly enhanced the area of therapy and imaging of targeted nanomedicine. Nanotheranostics, which make use of nanoparticles, are a significant advancement in MRI and CT imaging. In addition to giving high-resolution anatomical features and functional information simultaneously, these multifunctional agents improve contrast when used. In addition to enabling early disease detection, precise localization, and personalised therapy monitoring, they also enable early disease detection. Fusion of MRI and CT enables precise in vivo tracking of drug-loaded nanoparticles. MRI, which provides real-time monitoring of nanoparticle distribution, accumulation, and release at the cellular and tissue levels, can be used to assess the efficacy of drug delivery systems. The precise localization of nanoparticles within the body is achievable through the use of CT imaging. This technique enhances the capabilities of MRI by providing high-resolution anatomical information. CT also allows for quantitative measurements of nanoparticle concentration, which is essential for evaluating the pharmacokinetics and biodistribution of nanomedicine. In this article, we emphasize the integration of preclinical MRI and CT into molecular imaging and therapy for advanced diseases.

A polymeric 1H/19F dual-modal MRI contrast agent with a snowman-like Janus nanostructure.

Magnetic resonance imaging (MRI) has emerged as a pivotal tool in contemporary medical diagnostics, offering non-invasive and high-resolution visualization of internal structures. Contrast agents are essential for enhancing MRI resolution, accurate lesion detection, and early pathology identification. While gadolinium-based contrast agents are widely used in clinics, safety concerns have prompted exploration of metal-free alternatives, including fluorine and nitroxide radical-based MRI contrast agents. Fluorine-containing compounds exhibit excellent MRI capabilities, with 19F MRI providing enhanced resolution and quantitative assessment. Nitroxide radicals, such as PROXYL and TEMPO, offer paramagnetic properties for MRI contrast. Despite their versatility, nitroxide radicals suffer from lower relaxivity values (r1) compared to gadolinium. Dual-modal imaging, combining 1H and 19F MRI, has gained prominence for its comprehensive insights into biological processes and disease states. However, existing dual-modal agents predominantly utilize gadolinium-organic ligands without incorporating nitroxide radicals. Here, we introduce a novel dual-modal MRI contrast agent (J-CA) featuring a Janus asymmetric nanostructure synthesized via seeded emulsion polymerization and post-modification. J-CA demonstrates excellent in vitro and in vivo performance in both 19F and 1H MRI, with a T2 relaxation time of 5 ms and an r1 value of 0.31 mM-1 s-1, ensuring dual-modal imaging capability. Moreover, J-CA exhibits superior biocompatibility and organ targeting, making it a promising candidate for precise lesion imaging and disease diagnosis. This work introduces a new avenue for metal-free dual-modal MRI, addressing safety concerns associated with traditional contrast agents.

Structurally Optimized Fluorinated Small‐Sized Graphene Oxide for Enhanced Magnetic Resonance Imaging during Pregnancy

AbstractGadolinium‐based complex contrast agents (GBCAs), frequently applied in magnetic resonance imaging (MRI), are associated with severe acute anaphylactic shock and incurable nephrogenic systemic fibrosis. Besides, the repeated use of GBCAs may result in the accumulation in various tissues. Given these potential adverse effects, GBCAs have not been well used during pregnancy. Herein, a novel metal‐free T2‐weighted MRI nanoprobe, designated fluorinated small‐sized graphene oxide with optimized fluorine content (LF‐sGO), is developed via graphene oxide materials. By introducing specific polar C─F bonds onto the small‐sized graphene oxide (sGO) skeleton, the prepared nanoprobe exhibits excellent water solubility, as well as superior MRI capabilities, thereby furnishing high‐resolution MRI anatomical information. Furthermore, the free radicals on LF‐sGO stabilized by C─F bonds confer LF‐sGO enrichment in the tumor region, enabling comprehensive imaging capability. The cytotoxicity study in vitro indicates that LF‐sGO has the potential to serve as a biocompatible imaging probe. Moreover, detailed in vivo studies on pregnant mice and zebrafish adequately demonstrate that microinjection of LF‐sGO does not induce dysontogensis and teratogenesis. This study successfully showcases a metal‐free nanoprobe that exhibits exceptional MRI capabilities for the purpose of tumor diagnosis. Notably, this nanoprobe holds promise for safe and effective tumor diagnosis during pregnancy.

Amorphous 2D Mn-doped CoMo-layered double hydroxide nanosheets for magnetic resonance imaging-guided sonodynamic cancer therapy

Sonodynamic therapy (SDT) has attracted increasing attention owing to its superior tissue penetration compared with other therapies. However, the development of multifunctional sonosensitizers with imaging capability and high production efficiency of reactive oxygen species (ROS) is still a challenge for current sonodynamic cancer therapy. Herein, we report the design and preparation of amorphous 2D Mn-doped CoMo-layered double hydroxide (a-Mn-CoMo-LDH) nanosheets (NSs) through acid etching-induced crystalline-to-amorphous phase transformation as a highly active nano-agent for magnetic resonance imaging (MRI)-guided SDT. The a-Mn-CoMo-LDH NSs exhibit superior ROS production capacity compared with amorphous CoMo-LDH NSs (∼1.3 times) and crystalline Mn-CoMo-LDH NSs (∼3.9 times) under ultrasound (US) irradiation, which is ∼ 9.9 times of the previously reported TiO2 sonosensitizer. The doped Mn4+ in the a-Mn-CoMo-LDH NSs can not only decompose H2O2 into O2 to alleviate the hypoxia level in tumor microenvironment (TME), but also consume glutathione (GSH) to reduce its clearance of ROS, promoting the SDT performance synergistically. Importantly, the GSH consumption can partially reduce the Mn4+ to Mn2+ within the tumors, which can serve as an agent for T1-weighted MRI, thus endowing the a-Mn-CoMo-LDH NSs with excellent MRI capability. Therefore, the as-prepared a-Mn-CoMo-LDH NSs with polyethylene glycol modification can be used as an efficient nano-agent for MRI-guided SDT, which can effectively achieve apoptosis of cancer cells in vitro and eradication of tumors in vivo under US irradiation.

Advancements in the research of combining MRI and CRISPR technology for the treatment of breast cancer

Cancer remains a significant contributor to global mortality, posing a considerable public health challenge. Among the various types of cancer, breast cancer stands out as one of the most prevalent among women worldwide. Ongoing efforts are dedicated to the development of innovative treatments with minimal side effects. A groundbreaking genome technique for editing, CRISPR-associated protein-9 (Cas9), also known as clustered regularly interspaced short palindromic repeat (CRISPR), has become an effective instrument for genetic modification. This technology has revolutionized genome editing across diverse biological fields, including its applications in genome therapy and tumor research. With ongoing advancements in sensitivity, specificity, and diagnostic accuracy, magnetic resonance imaging (MRI) has gained increasing recognition for the detection of breast cancer. MRIs capability to produce high-resolution images plays a pivotal role in aiding healthcare professionals in precise localization of breast masses, tumors, and other abnormalities. Additionally, it facilitates the assessment of parameters like tumor size, extent, and lymph node involvement, contributing to the formulation of more accurate treatment strategies. Here is a review summary of the combined utilization of MRI and CRISPR technology in breast cancer treatment. It explores the synergy between these two technologies, discussing their advantages and disadvantages and their potential to enhance diagnostic and therapeutic outcomes.

Diagnostic capability of 18F-PSMA PET-MRI and pelvic MRI plus bone scan in treatment-naive prostate cancer: a single-center paired validating confirmatory study.

Radical prostatectomy with pelvic lymph node dissection for the treatment of high-risk localized prostate cancer (PCa) results in long-term benefits in selected patients. But insufficient sensitivity of conventional examinations which are pelvic MRI and bone scan, limits the diagnosis of bone and lymph node metastasis of PCa. This affects the surgical management strategy of a large number of patients. The purpose of this study was to investigate whether 18F-prostate-specific membrane antigen (PSMA) PET-MRI could improve the clinical detection of PCa metastases compared with the conventional pelvic MRI plus bone scan. From April 2020 to April 2023, we prospectively enroled 472 patients with histologically proven PCa in our centre, and 120 patients underwent 18F-PSMA PET-MRI, multiparametric MRI, and bone scan before laparoscopic radical prostatectomy plus lymph node dissection. The accuracy of imaging results in detecting lymph node and bone metastatic lesions was compared between PSMA PET-MRI and MRI plus bone scan. In diagnosing lymph node metastasis, PSMA PET-MRI had an area under the curve (AUC) of 0.844 (95% CI: 0.738-0.949, P < 0.001), sensitivity and specificity of 75% and 96%, which performed apparently better than MRI [AUC=0.615 (95% CI: 0.480-0.750, P =0.073)]. PSMA PET-MRI showed excellent expression in the diagnosis of bone metastases, with an AUC of 0.910 (95% CI: 0.840-0.981, P <0.001) compared to 0.700 (95% CI: 0.577-0.823, P =0.001) in bone scanning. PSMA PET-MRI also had higher sensitivity than bone scanning (90% vs. 43%), while lower specificity (92% vs. 97%). PSMA PET-MRI is superior to conventional imaging at diagnosing metastases in lymph nodes and bones in PCa and can provide a more accurate stagement.

Magnetic Resonance Imaging of Aerosol Deposition.

Nuclear magnetic resonance imaging (MRI) uses non-ionizing radiation and offers a host of contrast mechanisms with the potential to quantify aerosol deposition. This chapter introduces the physics of MRI, its use in lung imaging, and more specifically, the methods that are used for the detection of regional distributions of inhaled particles. The most common implementation of MRI is based on imaging of hydrogen atoms (1H) in water. The regional deposition of aerosol particles can be measured by the perturbation of the acquired 1H signals via labeling of the aerosol with contrast agents. Existing in vitro human and in vivo animal model measurements of regional aerosol deposition in the respiratory tract are described, demonstrating the capability of MRI to assess aerosol deposition in the lung.