ATP (adenosine triphosphate) and HMGB1 (high mobility group box 1 protein) are key players in treatments that induce immunogenic cell death (ICD). However, conventional therapies, including radiotherapy, are often insufficient to induce ICD. In this study, we explore a strategy using nanoparticle-loaded macrophages as a source of ATP and HMGB1 to complement radiation-induced intrinsic and adaptive immune responses.
View Article and Find Full Text PDFMerTK PET imaging holds potential as a promising approach for assessing tumor aggressiveness and monitoring treatment response. In this study, we synthesized a series of F- and Ga-labeled tracers derived from MerTK inhibitors for detection of MerTK expression. Among the synthesized agents, the dimeric compounds [Ga] and [Ga] demonstrated good and stability, high affinities to the MerTK receptor, and good MerTK-targeting specificity.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
September 2024
Supramolecular assembly allows multiple chemical/bio-components integrated as one system for cascade biochemical reactions. Herein the graphitic carbon nitrides (g-CN) as photocatalyst trapped in a dipeptide hydrogel covering adenosine triphosphate (ATP) synthase accelerates the photophosphorylation through ATP synthesis. Self-assembled N-fluorenylmethoxycarbonyl diphenylalanine (Fmoc-FF) as nanofibrils to allow g-CN nanosheets are embedded as a complex Fmoc-FF/g-CN hydrogel.
View Article and Find Full Text PDFA 2-phenyl-3-difluoromethoxy-pyridinyl moiety features in potent phosphodiesterase 4D inhibitors that are considered to be candidate radiotracers for positron emission tomography if they are labeled with fluorine-18. Fluorine-18 could be installed as desired at the 3'-phenyl position with acridinium-mediated photoredox radiodeoxyfluorination in homologues bearing variously substituted 3'-aryloxy groups. However, a distal 3-difluoromethoxide (-OCHF) group strongly competes as a leaving group, especially when an electron-deficient aryloxy group is present at position 3'.
View Article and Find Full Text PDFTo avoid the harsh conditions that are oftentimes adopted in direct radiofluorination reactions, conjugation of bioactive ligands with F-labeled prosthetic groups has become an important strategy to construct novel PET agents under mild conditions when the ligands are structurally sensitive. Prosthetic groups with [F]fluoroarene motifs are especially appealing because of their stability in physiological environments. However, their preparation can be intricate, often requiring multistep radiosynthesis with functional group conversions to prevent the decomposition of unprotected reactive prosthetic groups during the harsh radiofluorination.
View Article and Find Full Text PDFIn the past decades, the therapeutic effect of glioblastoma (GBM) has not been significantly improved. Generous evidence indicates that S100A9 has a wide range of functions in tumors, but its exploration in GBM is less. The purpose of this study is to conduct a comprehensive bioinformatics analysis and cytological experiment on S100A9 in GBM.
View Article and Find Full Text PDFAbnormal tumor metabolism creates a complex tumor immune microenvironment that plays a dominant role in the metastasis of triple-negative breast cancer (TNBC). TNBC is insensitive to immune checkpoint blockade (ICB) therapy because of insufficient cytotoxic T lymphocyte (CTL) infiltration and a hyper-lactic acid-suppressive immune microenvironment caused by abnormal glycolysis. Herein, we propose an amplified strategy based on lactic acid regulation to reprogram the immunosuppressive tumor microenvironment (ITM) and combine it with ICB therapy to achieve enhanced antitumor immunotherapy effects.
View Article and Find Full Text PDFPhotoredox is a powerful synthetic tool in organic chemistry and has been widely used in various fields, including nuclear medicine and molecular imaging. In particular, acridinium-based organophotoredox radiolabeling has significantly impacted the production and discovery of positron emission tomography (PET) agents. Despite their extensive use in preclinical research, no PET agents synthesized by acridinium photoredox labeling have been tested in humans.
View Article and Find Full Text PDFWith the gradual shift of coal mining to the western coal mining region of China, floor heave in weakly cemented mudstone roadways has become an issue affecting the safety and efficiency of coal mine production. Additionally, different mining rates can lead to fluctuating support stresses on the roof and floor of weakly cemented mudstone roadways. Therefore, obtaining a comprehensive understanding of the mechanical properties of weakly cemented mudstone at different loading rates is conducive to improving the issue of floor heave in such roadways and provides a theoretical basis for further study.
View Article and Find Full Text PDFArbuscular mycorrhizal fungi (AMF) influence silicon (Si) uptake by plants, but the mechanisms remain unclear. This study investigated the mechanisms of AMF-mediated Si uptake by rice, a model Si-accumulating plant, and explored the tripartite interactions among AMF, Si, and phosphorus (P). AMF inoculation increased shoot Si content by 97% when supplied with silicic acid and by 29% with calcium silicate and upregulated expression of Si transporters and in roots.
View Article and Find Full Text PDFHepatic stellate cells (HSCs) are a major source of fibrogenic cells and play a central role in liver fibrogenesis. HSC activation depends on metabolic activation, for which it is well established that fatty acid oxidation (FAO) sustains their rapid proliferative rate. Studies have indicated that tanshinones inhibit HSC activation, however, the anti-fibrosis mechanisms of tanshinones are remain unclear.
View Article and Find Full Text PDFJ Nucl Med
August 2024
The development of theranostic radiotracers relies on their binding to specific molecular markers of a particular disease and the use of corresponding radiopharmaceutical pairs thereafter. This study reports the use of multiamine macrocyclic moieties (MAs), as linkers or chelators, in tracers targeting the neurotensin receptor-1 (NTSR-1). The goal is to achieve elevated tumor uptake, minimal background interference, and prolonged tumor retention in NTSR-1-positive tumors.
View Article and Find Full Text PDFProtein aggregation caused by the disruption of proteostasis will lead to cellular cytotoxicity and even cell death, which is implicated in multiple neurodegenerative diseases. The elimination of aggregated proteins is mediated by selective macroautophagy receptors, which is termed aggrephagy. However, the identity and redundancy of aggrephagy receptors in recognizing substrates remain largely unexplored.
View Article and Find Full Text PDFHypoimmunogenicity and the immunosuppressive microenvironment of ovarian cancer severely restrict the capability of immune-mediated tumor killing. Immunogenic cell death (ICD) introduces a theoretical principle for antitumor immunity by increasing antigen exposure and presentation. Despite recent research progress, the currently available ICD inducers are still very limited, and many of them can hardly induce sufficient ICD based on traditional endoplasmic reticulum (ER) stress.
View Article and Find Full Text PDFBackground: Peanut (Arachis hypogaea), a vital oil and food crop globally, is susceptible to web blotch which is a significant foliar disease caused by Phoma arachidicola Marasas Pauer&Boerema leading to substantial yield losses in peanut production. Calcium treatment has been found to enhance plant resistance against pathogens.
Results: This study investigates the impact of exogenous calcium on peanut resistance to web blotch and explores its mechanisms.
Purpose: Accumulating evidence suggests that neurotensin (NTS) and neurotensin receptors (NTSRs) play key roles in lung cancer progression by triggering multiple oncogenic signaling pathways. This study aims to develop Cu-labeled neurotensin receptor 1 (NTSR1)-targeting agents with the potential for both imaging and therapeutic applications.
Method: A series of neurotensin receptor antagonists (NRAs) with variable propylamine (PA) linker length and different chelators were synthesized, including [Cu]Cu-CB-TE2A-iPA-NRA ([Cu]Cu-4a-c, i = 1, 2, 3), [Cu]Cu-NOTA-2PA-NRA ([Cu]Cu-4d), [Cu]Cu-DOTA-2PA-NRA ([Cu]Cu-4e, also known as [Cu]Cu-3BP-227), and [Cu]Cu-DOTA-VS-2PA-NRA ([Cu]Cu-4f).
In this study, we introduce a practical methodology for the synthesis of PET probes by seamlessly combining flow chemistry with photoredox radiofluorination. The clinical PET tracer 6-[F]FDOPA was smoothly prepared in a 24.3% non-decay-corrected yield with over 99.
View Article and Find Full Text PDFObjective And Design: Mast cells (MCs), as the fastest immune responders, play a critical role in the progression of neuroinflammation-related diseases, especially in depression. Quercetin (Que) and kaempferol (Kae), as two major diet-derived flavonoids, inhibit MC activation and exhibit significant antidepressant effect due to their anti-inflammatory capacity. The study aimed to explore the mechanisms of inhibitory effect of Que and Kae on MC activation, and whether Que and Kae suppress hippocampal mast cell activation in LPS-induced depressive mice.
View Article and Find Full Text PDFRNA modifications have been substantiated to regulate the majority of physiological activities in the organism, including the metabolism of reactive oxygen species (ROS), which plays an important role in cells. As for the effect of RNA modification genes on ROS metabolism in glioblastoma (GBM), it has not been studied yet. Therefore, this study aims to screen the RNA modification genes that are most related to ROS metabolism and explore their effects on the biological behavior of GBM .
View Article and Find Full Text PDFThe past decade has seen a remarkable growth in the number of bioconjugation techniques in chemistry, biology, material science, and biomedical fields. A core design element in bioconjugation technology is a chemical reaction that can form a covalent bond between the protein of interest and the labeling reagent. Achieving chemoselective protein bioconjugation in aqueous media is challenging, especially for generally less reactive amino acid residues, such as tryptophan.
View Article and Find Full Text PDFCobalt-sarcophagine complexes exhibit high kinetic inertness under various stringent conditions, but there is limited literature on radiolabeling and in vivo positron emission tomography (PET) imaging using no carrier added Co. To fill this gap, this study first investigates the radiolabeling of DiAmSar (DSar) with Co, followed by stability evaluation in human serum and EDTA, pharmacokinetics in mice, and a direct comparison with [Co]CoCl to assess differences in pharmacokinetics. Furthermore, the radiolabeling process was successfully used to generate the NTSR1-targeted PET agent [Co]Co-NT-Sarcage (a DSar-functionalized SR142948 derivative) and administered to HT29 tumor xenografted mice.
View Article and Find Full Text PDFSex pheromone recognition is essential for mating in many insects and plays a major role in maintaining reproductive barriers. A previous study from our lab reported the evolutionary history of the pheromone receptor OR5 in moths. Using heterologous expression in oocytes and site-directed mutagenesis, we found that eight amino acid substitutions were sufficient to recapitulate the evolution from an ancestral broadly-tuned to a highly specific receptor.
View Article and Find Full Text PDFRecently, bioinspired fluorescent materials have drawn ever-increasing attention due to their ecofriendliness and easy accessibility. Herein, we demonstrate that anthraquinone/metal ion coordination complexes can form well-defined crystals and possess obvious fluorescence enhancement properties. The fluorescence quantum yields of anthraquinone/metal ion assemblies are more than 2 orders of magnitude compared to those of anthraquinone assemblies.
View Article and Find Full Text PDFThe small-molecule iododiflunisal (IDIF) is a transthyretin (TTR) tetramer stabilizer and acts as a chaperone of the TTR-Amyloid beta interaction. Oral administration of IDIF improves Alzheimer's Disease (AD)-like pathology in mice, although the mechanism of action and pharmacokinetics remain unknown. Radiolabeling IDIF with positron or gamma emitters may aid in the in vivo evaluation of IDIF using non-invasive nuclear imaging techniques.
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