Search Results (425)

Gadolinium-doped hydroxyapatite nanoparticles (HapGd NPs) have emerged as promising multifunctional platforms for biomedical applications due to their unique combination of biocompatibility, structural tunability, and magnetic responsiveness. In this work, HapGd nanoparticles were synthesized using a microwave-assisted method and subsequently functionalized with curcumin and folic acid to enhance therapeutic efficiency and selective targeting. The synthesized nanostructures were characterized using various techniques, including X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), vibrating sample magnetometry (VSM), and relaxometry. Structural analyses revealed successful incorporation of Gd³⁺ ions into the Hap lattice, resulting in reduced unit cell volume and slight lattice distortion, while preserving the apatite crystalline framework. Surface functionalization with curcumin and folic acid was confirmed through spectroscopic characterization, demonstrating effective molecular attachment. Nuclear Magnetic Resonance (NMR) relaxation measurements indicated that Gd doping endowed paramagnetic behavior suitable for contrast enhancement in magnetic resonance imaging (MRI). Relaxometry studies revealed a strong linear correlation between 1/T₁ and the Gd³⁺ concentration, especially in the functionalized samples, with performance comparable to the commercial contrast agent Omniscan™. The developed HapGd-based nanoplatform exhibits integrated diagnostic and therapeutic potential, providing a foundation for future research in biomedical applications. Full article

The increasing demand for sustainable and functional plant-based foods has driven interest in 3D food printing technologies, which require bioinks with tailored rheological and structural properties. This study investigated the effects of transglutaminase (TGase) on the structure–function relationships of plant protein bioinks from fava bean, mung bean, pea, and soybean. TNBS assays showed a dose-dependent increase in crosslinking (27.46–64.57%), with soybean and pea proteins exhibiting the highest reactivity (p < 0.05). ¹H-NMR confirmed protein-specific ε-(γ-glutamyl)lysine bond formation, and synchrotron FTIR revealed TGase-induced α-helix reduction and β-sheet enrichment, indicative of network formation across all proteins. SDS-PAGE analysis demonstrated TGase-mediated polymerization with high-molecular-weight aggregates, particularly pronounced in soybean, while SEM images revealed denser, more continuous protein networks compared to untreated samples. Rheological characterization showed enhanced viscoelasticity and shear-thinning behavior in all bioinks, supporting extrusion and post-printing stability. Textural analysis indicated improvements in hardness, springiness, cohesiveness, and chewiness across all proteins, with soybean and fava showing the most pronounced increases. These results demonstrate that TGase is a versatile tool for reinforcing plant protein networks, improving printability, structural integrity, and texture in 3D-printed foods, while highlighting protein-specific differences in response. Full article

Quercus texana seeds are recalcitrant and thus highly sensitive to desiccation, which makes storage difficult. For practical seed handling, it is important to define their safe water content and to understand how water is distributed during dehydration. The present study utilized magnetic resonance imaging (MRI) and nuclear magnetic resonance (NMR) technologies to investigate the migration and phases of water, respectively, revealing the underlying reasons for the recalcitrance of Q. texana seeds. The water content of fresh Q. texana seeds was found to be 39.6% and the germination percentage was 93.3%. As the water content decreased, the germination percentage decreased continuously, reaching 0% at a water content of 13.0%. At 20.0% water content, the germination percentage was 71.7%. MRI showed that water was primarily stored in the embryo axis and cotyledon center in fresh Q. texana seeds. Water loss occurs in the following order during seed dehydration: embryo axis, cotyledon center, cotyledon periphery, and cotyledon end. However, water in the radicle region persisted until seed water content decreased to 15.0%, at which point no signal was detected. The NMR T₂ relaxation spectrum indicated the presence of bound water (T₂₁ = 0.01–5.44 ms) and free water (T₂₂ = 7.19–1401.93 ms) in the seeds. During the dehydration process, most of the water was lost as free water, and the T₂₂ shifted to longer times. Concurrently, the bound water shifted to shorter T₂₁ times. Overall, for practical purposes, seed water should be maintained at or above 20.0%. MRI further showed that water loss from the radicle plays a decisive role in the decline of seed germination, and that protecting the region of radicle and the cupule scar can effectively retard water loss. Furthermore, the bound-water content is positively correlated with seed germination. Full article

Background: Triple-negative breast cancer (TNBC) remains primarily treated with chemotherapy due to the lack of effective therapeutic targets, but this approach carries significant systemic toxicity and a high risk of drug resistance. Curcumin (Cur), despite its multifaceted antitumor activity, faces limitations in clinical application due to poor water solubility and weak targeting properties. This study aims to develop a folate/mitochondria dual-targeted curcumin–copper chelate liposome (Cu-Cur DTLPs) formulation that enables copper accumulation within tumor cells and induces copper-mediated cell death, thereby providing an effective and relatively low-toxicity therapeutic strategy for triple-negative breast cancer. Methods: Curcumin–copper chelates (Cu-Cur) were first synthesized and characterized using mass spectrometry, NMR, and infrared spectroscopy. Subsequently, dual-targeted liposomes (Cu-Cur DTLPs) were prepared via the thin-film dispersion method, with systematic evaluation of particle size, zeta potential, encapsulation efficiency, and in vitro release profiles. In vitro cytotoxicity was assessed against 4T-1 and MDA-MB-231 cells using the MTT assay. In a 4T-1 tumor-bearing BALB/c mouse model, comprehensive evaluation of targeting efficiency, antitumor efficacy, and mechanisms of action was conducted via in vivo imaging, tumor volume monitoring, immunohistochemistry (detecting FDX1 and DLAT proteins), and TUNEL staining. Results: Cu-Cur DTLPs with a uniform particle size of approximately 104.4 nm were successfully synthesized. In vitro and in vivo studies demonstrated that compared to free curcumin and conventional liposomes, Cu-Cur DTLPs significantly enhanced drug accumulation in tumor tissues and exhibited effective tumor growth inhibition. Mechanistic studies confirmed that this formulation specifically accumulates copper ions within tumor cells, upregulates FDX1, promotes DLAT oligomerization, and induces mitochondrial dysfunction, thereby driving copper death. TUNEL staining ruled out apoptosis as the primary mechanism. Safety evaluation revealed no significant toxicity in major organs. Conclusions: The Cu-Cur DTLPs developed in this study effectively induce copper-mediated death in TNBC through a dual-targeted delivery system, significantly enhancing antitumor activity with favorable safety profiles. This establishes a highly promising novel nanotherapeutic strategy for TNBC treatment. Full article

Recent applications of low-field NMR in alkali-activated materials (AAMs) often adopt interpretation models developed for Portland cement systems, overlooking the distinct influences of paramagnetic/ferrimagnetic components and free-water redistribution. This study investigates how paramagnetic or ferrimagnetic component and free water distribution influence low-field nuclear magnetic resonance (LF-NMR) and proton density magnetic resonance imaging (PD-MRI) characterization of alkali-activated materials (AAMs). Blast furnace slag, fly ash, and steel slag were activated with NaOH solution at liquid-to-solid ratios of 0.45 and 0.5, and analyzed across top, middle, and bottom layers. Slurries prepared with less mixing water and CaO-rich raw materials exhibited negligible settling and uniform relaxation behavior, whereas those with higher water content and CaO-deficient raw materials showed pronounced stratification, resulting in distinct gradients in signal intensity. The results indicate that the LF-NMR data interpretation of relatively dilute system may be unreliable as the relaxation time of protons will be extended after they transfer from bottom to the top of the slurry. A preliminary method for assessing slurry suitability for LF-NMR characterization is proposed for future validation. Full article

Accurate malaria diagnosis is essential for effective case management and transmission control; however, the sensitivity, operational requirements, and field applicability of current conventional methods are limited. Hemozoin, an optically and magnetically active crystalline biomarker produced by Plasmodium species, offers a reagent-free target for next-generation diagnostics. This scoping review, following PRISMA-ScR and Joanna Briggs Institute guidance, synthesizes recent advances in hemozoin-based detection technologies and maps the current landscape. Twenty-four studies were reviewed, spanning eight major technology classes: magneto-optical platforms, magnetophoretic microdevices, photoacoustic detection, Raman/SERS spectroscopy, optical and hyperspectral imaging, NMR relaxometry, smartphone-based microscopy, and flow cytometry. Magneto-optical systems—including Hz-MOD, Gazelle™, and RMOD—demonstrated the highest operational readiness, with robust specificity but reduced sensitivity at low parasitemia. Photoacoustic Cytophone studies demonstrated promising sensitivity and noninvasive in vivo detection. Raman/SERS platforms achieved sub-100 infected cell/mL analytical sensitivity but remain laboratory-bound. Microfluidic and smartphone-based tools offer emerging, potentially low-cost alternatives. Across modalities, performance varied by parasite stage, with reduced detection of early ring forms. In conclusion, hemozoin-targeted diagnostics represent a rapidly evolving field with multiple viable translational pathways. While magneto-optical devices are closest to field deployment, further clinical validation, improved low-density detection, and standardized comparison across platforms are needed to support future adoption in malaria-endemic settings. Full article

Background/Objectives: High-grade glioma shows marked metabolic heterogeneity. We performed a PRISMA-guided systematic review and meta-analysis to quantify PET accuracy for pseudoprogression (PsP) and for recurrence/progression versus treatment-related change (TRC), assess pool baseline associations with overall (OS) and progression-free survival (PFS), summarize PET-based prediction of molecular markers, and assess the PET–stereotactic biopsy–ex vivo metabolomics workflow. Methods: We searched PubMed/MEDLINE and the Web of Science Core Collection (Clarivate) from inception to 1 September 2025 for HGG cohorts with baseline PET. Eligibility: Adults with HGG; diagnostic syntheses required per-patient 2 × 2; prognostic syntheses required for HR with 95% CI. Risk of bias: QUADAS-2 (diagnostic) and QUIPS (prognostic). Random-effects models pooled log-HRs and sensitivity/specificity; molecular studies were summarized by AUCs. Imaging-to-omics concordance was reviewed narratively owing to the absence of co-registered PET–metabolite maps in human HGG. Results: The results included the following: OS k = 10; PFS k = 3; PsP k = 2 (N = 76); and TRC k = 3 (N = 152). For PsP, two amino acid PET cohorts yielded a sensitivity of 0.943 and a specificity of 0.826. For TRC, pooled FDOPA across two cohorts gave rise to a sensitivity of 0.879 and a specificity of 0.771. OS meta-analyses were non-significant under Hartung–Knapp modification—FDG HR of 1.09 (95% CI 0.69–1.73) and amino acid HR of 1.03 (0.72–1.46)—with substantial heterogeneity. PFS effects varied by tracer/metric; examples include FDOPA HR of 7.92 (2.17–28.90) and MET metabolic tumor volume HR of 1.60 (1.20–2.30). Conclusions: Amino acid PET is sensitive to PsP and, with FDOPA, aids TRC discrimination when MRI is equivocal, whereas baseline PET–survival associations are weak and heterogeneous. Prospective co-registered PET/MR with stereotactic biopsies and HR-MAS NMR spectroscopy/MALDI-MSI is required to quantify imaging-to-omics concordance and standardize spatial endpoints. Study registration: PROSPERO CRD420251113416. Funding: none. Full article

The rhenium(I) tricarbonyl complex fac-[Re(CO)₃(5,6-epoxy-5,6-dihydro-1,10-phenanthroline)Br] (ReL) has previously demonstrated promising luminescent properties, enabling its direct application as a probe for walled cells such as Candida albicans and Salmonella enterica. In this new study, we present a significantly expanded and comprehensive characterization of ReL, incorporating a wide range of experimental and computational techniques not previously reported. These include variable-temperature ¹H and ¹³C NMR spectroscopy, CH-COSY, single-crystal X-ray diffraction, Hirshfeld surface analysis, DFT calculations, Fukui functions, non-covalent interaction (NCI) indices, and electrochemical profiling. Structural analysis confirmed a pseudo-octahedral geometry with the bromide ligand positioned cis to the epoxy group. NMR data revealed the coexistence of cis and trans isomers in solution, with the trans form being slightly more stable. DFT calculations and aromaticity descriptors indicated minimal electronic differences between isomers, supporting their unified treatment in subsequent analyses. Electrochemical studies revealed two oxidation and two reduction events, consistent with ECE and EEC mechanisms, including a Re(I) → Re(0) transition at −1.50 V vs. SCE. Theoretical redox potentials showed strong agreement with experimental data. Biological assays revealed a dose-dependent cytotoxic effect on HeLa cells, contrasting with previously reported low toxicity in microbial systems. These findings, combined with ReL’s luminescent and antimicrobial properties, underscore its multifunctional nature and highlight its potential as a bioactive and imaging agent for advanced therapeutic and microbiological applications. Full article

This study uniquely explores the impact of a novel natural antifreeze peptide derived from grass carp (GCAFP) on the freeze–thaw characteristics and structural stability of wet gluten protein, providing new insights into the development of natural cryoprotectants for frozen foods. The effects of GCAFP on the physicochemical and structural properties of gluten protein were investigated using differential scanning calorimetry (DSC), nuclear magnetic resonance imaging (NMR), rheology, and scanning electron microscopy (SEM). The results showed that the addition of 0.5% GCAFP significantly reduced the freezing temperature (T_f, from −8.50 ± 1.31 °C to −10.75 ± 2.49 °C) and expanded the melting temperature range (T_m,δ, from 3.60 ± 1.40 °C to 5.65 ± 0.12 °C), indicating improved freezing stability. After five weeks of frozen storage, the ice crystal melting enthalpy (ΔH_m) of gluten protein in the GCAFP group increased by only 20.17 J/g, compared with 27.23 J/g in the control, representing a 6.35% reduction (p < 0.05). Similarly, after five freeze–thaw cycles, the freezable water fraction (F_w) and ΔH_m were reduced by 5.19% and 1.55%, respectively, demonstrating that GCAFP inhibited water migration and ice recrystallization. Low-field NMR revealed that GCAFP maintained a higher proportion of bound water (T21) and decreased free water (T23), confirming its role in restricting water mobility. Rheological analysis showed that GCAFP preserved the viscoelasticity of gluten protein, maintaining higher storage (G′) and loss (G″) moduli than the control after five freeze–thaw cycles, thus mitigating the decline in network elasticity. Structural characterization indicated that GCAFP stabilized the α-helix and β-sheet contents, reduced glutenin macropolymer depolymerization from 24.85% to 18.95%, and strengthened hydrogen bonding within the protein matrix. Overall, GCAFP effectively protected wet gluten protein against ice crystal damage by maintaining water distribution, viscoelasticity, and secondary structure integrity, highlighting its potential as a natural antifreeze ingredient for frozen food applications. Full article

RNA modifications are essential regulators of gene expression and cellular function, modulating RNA stability, splicing, translation, and localization. Dysregulation of these modifications has been linked to cancer, neurodegenerative disorders, viral infections, and other diseases. Precise quantification and mapping of RNA modifications are crucial for understanding their biological roles. This review summarizes current and emerging methodologies for RNA modification analysis, including mass spectrometry, antibody-based and non-antibody-based approaches, PCR- and NMR-based detection, chemical- and enzyme-assisted sequencing, and nanopore direct RNA sequencing. We also highlight advanced techniques for single-cell and single-molecule imaging, enabling the study of modification dynamics and cellular heterogeneity. The advantages, limitations, and challenges of each method are discussed, providing a framework for selecting appropriate analytical strategies. Future perspectives emphasize high-throughput, multiplexed, and single-cell approaches, integrating multiple technologies to decode the epitranscriptome. These approaches form a robust toolkit for uncovering RNA modification functions, discovering biomarkers, and developing novel therapeutic strategies. Full article

This article is devoted to the synthesis and investigation of a family of new benzimidazole compounds with a propylsulfonate moiety, synthesized by condensation of salicylic aldehyde or its 5-substituted derivatives with 3-(2,3-dimethylbenzimidazol-1-ium-1-yl)propane-1-sulfonate. The structure of the obtained dyes was confirmed using NMR, FT-IR, and HRMS. Absorption and photoluminescence properties were studied in phosphate buffers over a wide pH range, and changes in the absorption and fluorescence spectra of DMSO solutions upon titration with DIPEA and HCl were also studied. It was found that all the target compounds possess pH-sensitive optical properties and can be used as fluorescent probes, while methoxycarbonyl-substituted derivative 3c demonstrated the most prominent optical and fluorescent response starting from pH ~ 4.5. The toxicity of the compounds was studied using whole-cell bioluminescent bacterial sensors. The effect on the biomass and metabolic activity of strains Staphylococcus aureus ATCC 6538-P FDA 209-P and Escherichia CDC F-50 bacterial biofilms was also investigated. In the final stage of the study, bioimaging experiments were carried out using the selected most promising dye 3c and biofilms. It was demonstrated that the dye can be excited by light with wavelengths of 458 nm or 750 nm in multiphoton mode. Importantly, when biofilms are incubated in the dye solution for 3 h, only the extracellular matrix is stained. However, if the staining time is increased to 24 h, dye penetration into bacterial cells is observed, resulting in a second photoluminescence maximum during sample analysis. It is important to note that when biofilms are incubated in a dye solution for 3 h, only the extracellular matrix is stained, while with longer staining, penetration of the dye into bacterial cells is observed, and a second photoluminescence maximum appears during sample analysis. The results obtained demonstrate a high potential of using benzimidazole-based compounds as pH-sensitive fluorescent probes operating in a biologically relevant pH range, which can be used for imaging of bacterial biofilms. Full article

This article presents a comprehensive overview of the current and emerging roles of cryogenics and superconductivity in medical diagnostics, imaging, and therapy. Beginning with the historical foundations of both fields and their technological maturation, this review emphasizes how cryogenic engineering and superconducting materials have become indispensable to modern medical systems. Cryogenic technologies are highlighted in applications such as cryosurgery, cryotherapy, cryostimulation, and cryopreservation, all of which rely on controlled exposure to extremely low temperatures for therapeutic or biological preservation purposes. This article outlines the operating principles of cryomedical devices, the refrigerants and cooling methods used, and the technological barriers. This paper reviews the latest applications of superconductivity phenomena in medicine and identifies those that could be used in the future. These include cryogenic therapy, radiotherapy (cyclotrons, particle accelerators, synchrotron radiation generation, isotope production, and proton and ion beam delivery), magnetic resonance imaging (MRI), nuclear magnetic resonance spectroscopy (NMR), positron emission tomography (PET), and ultra-sensitive magnetic signal transducers based on SQUIDs for detecting ultra-low bio-signals emitted by human body organs. CT, MRI/NMR, and PET features are compared using the operation principle, specific applications, safety, contraindications for patients, examination time, and additional valued peculiarities. This article outlines the prospects for the development of superconducting and cryogenic materials and technologies in medical applications. Advances in diagnostic imaging are reviewed, with particular attention on the progression from conventional MRI scanners to ultra-high-field (UHF) systems exceeding 7–10.5 T, culminating in the 11.7 T Iseult whole-body MRI magnet. Another important application area described in this article includes biofunctionalized magnetic nanoparticles and superconducting quantum interference devices (SQUIDs), which enable the ultrasensitive detection of biomagnetic fields and targeted cancer diagnostics. Finally, this article identifies future directions of development in superconducting and cryogenic technologies for medicine. Full article

The exploration potential, storage capacity, and exploitability of the deep shale-gas reservoirs are governed by various characteristics of their pore networks. Conventional methods cannot fully capture these features across scales, highlighting the need for an integrated, multi-technique approach. In this study, pore structure and connectivity of the Wufeng–Longmaxi Formation (Luzhou Block) were investigated using Scanning Electron Microscopy (SEM) with the Mosaic Acquisition and Positioning System (MAPS), ImageJ (ImageJ 2.14.0)-based pore analysis, Mercury Intrusion Porosimetry (MIP), and Nuclear Magnetic Resonance (NMR). Based on the samples from eight reservoir layers of Wufeng-WF and Longmaxi-LM1₁^1–7, shale pore connectivity was classified into three grades. Grade A layers, with connected pore volumes above 0.0067 cm³/g and porosity exceeding 1.75%, showed trimodal NMR pore-size distributions and strong connectivity among micro, meso, and macropores. Grade B layers exhibited bimodal pore distributions, moderate pore connectivity (0.0057–0.0067 cm³/g; 1.55–1.75% porosity), and sponge-like organic pores with isolated mineral pores. Grade C layers, with connected pore volumes below 0.0057 cm³/g, showed poor connectivity and unimodal NMR responses. Connected pores (1–100 nm) contributed 20–35% of total pore volume, reflecting the strong heterogeneity of the formation. Interconnected inorganic mineral-hosted pores were found to link locally connected organic pores, forming continuous pore networks. The qualitative and quantitative identification of the pore connectivity of shale reservoirs with MAPS, MIP, and NMR approach provides a robust framework for evaluating shale pore connectivity and identifying high-quality reservoir targets. Full article

Iron (Fe) chelators are used to treat iron-overloaded disorders, metal detoxification, radionuclides, and molecular imaging; however, they can cause side effects. In this study, we identified and characterized Coprogen B (CPGB), a hexadentate trihydroxamate siderophore secreted by the opportunistic dimorphic fungus Talaromyces marneffei and compared its properties with deferoxamine (DFO). Siderophore production was enriched from a ΔsreA strain and purified via Amberlite XAD2 and Sephadex LH20 chromatography, followed by reverse-phase HPLC. Active fractions were confirmed by Ultraviolet–Visible (UV–Vis) spectral fingerprints (≈230 nm) for hydroxamate, with a band at 430–450 nm upon Fe(III) complexation, as well as by chrome azurol A assay, Nuclear Magnetic Resonane (NMR) spectroscopy, High-Performance Liquid Chromatography–Mass Spectrometry (HPLC-MS), and Matrix-Assisted Laser Desorption/Ionization–Time-of-Flight Mass Spectrometry (MALDI-TOF-MS). CPGB exhibited strong molar absorptivity and rapid, concentration-dependent chelation of Fe(III), yielding a sustained binding profile that matched or exceeded that of DFO over time. In determining n-octanol/water partitioning for CPGB and DFO (230 nm) and their Fe(III) complexes, the partitioning (P) assay revealed that CPGB was moderately hydrophilic (P = 0.505 ± 0.063; cLogP = −0.299 ± 0.053), while DFO was strongly hydrophilic (P = 0.098 ± 0.005; cLogP = −1.010 ± 0.022). Fe(III) complexation reduced lipophilicity: CPGB–Fe partitioned ~30–35% into octanol, while DFO–Fe complex partitioned ~7–8%, remaining largely aqueous. Overall, this outcome potentially suggested improved clearance in vivo. These data nominate CPGB as a promising alternative to existing iron chelators. The siderophore exhibited greater lipophilicity, emphasizing better passive membrane permeability than DFO, while siderophore–Fe(III) binding indicated increased biases toward the aqueous phase. Future in vivo studies are warranted to confirm its pharmacokinetics, safety, and therapeutic efficacy. Full article