Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 184
Filtrar
1.
JACS Au ; 4(6): 2211-2219, 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38938815

RESUMO

Molten NaF-BeF2 salt is widely considered a promising candidate to replace FLiBe in molten salt reactor applications, which is crucial to reducing the operating costs of the molten salt reactor. Studies on beryllium compounds are rarely conducted due to their volatility and high toxicity. Herein, the Be-F coordination structure of NaF/BeF2 mixed salts was investigated in-depth through various HT-NMR and solid-state NMR methods, which are optimized to be appropriate for the detection of beryllium compounds. It was found that Na2BeF4 and NaBeF3 crystals were transformed into amorphous tetrahedral coordinated networks when there was an increase in the BeF2 concentration in the mixed salts. The main coordinate structure comparisons between FNaBe and FLiBe were analyzed, which exhibit high similarity due to the covalent effect of Be-F bonding, demonstrating the theoretical feasibility of applying FNaBe salts as a substitute for FLiBe in MSR systems. In addition, the transition from the crystal phase to the amorphous phase occurred at a lower BeF2 concentration for FNaBe than that for FLiBe. This was further verified by the results of ab initio molecular dynamics (AIMD) simulation that FNaBe melts had more disordered structures, thus causing slight changes in their physical properties.

2.
Chem Sci ; 15(25): 9649-9656, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38939140

RESUMO

With the increasing attention paid to macrocyclic scaffolds in peptide drug development, genetically encoded peptide macrocycle libraries have become invaluable sources for the discovery of high-affinity peptide ligands targeting disease-associated proteins. The traditional phage display technique of constructing disulfide-tethered macrocycles by cysteine oxidation has the inherent drawback of reduction instability of the disulfide bond. Chemical macrocyclization solves the problem of disulfide bond instability, but the involved highly electrophilic reagents are usually toxic to phages and may bring undesirable side reactions. Here, we report a unique Sortase-mediated Peptide Ligation and One-pot Cyclization strategy (SPLOC) to generate peptide macrocycle libraries, avoiding the undesired reactions of electrophiles with phages. The key to this platform is to mine the unnatural promiscuity of sortase on the X residue of the pentapeptide recognition sequence (LPXTG). Low reactive electrophiles are incorporated into the X-residue side chain, enabling intramolecular cyclization with the cysteine residue of the phage-displayed peptide library. Utilizing the genetically encoded peptide macrocycle library constructed by the SPLOC platform, we found a high-affinity bicyclic peptide binding TEAD4 with a nanomolar KD value (63.9 nM). Importantly, the binding affinity of the bicyclic peptide ligand is 102-fold lower than that of the acyclic analogue. To our knowledge, this is the first time to mine the unnatural promiscuity of ligases to generate peptide macrocycles, providing a new avenue for the construction of genetically encoded cyclic peptide libraries.

3.
ACS Appl Mater Interfaces ; 16(26): 34386-34392, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38869156

RESUMO

Highly crystalline and easily feasible topological insulator-superconductor (TI-SC) heterostructures are crucial for the development of practical topological qubit devices. The optimal superconducting layer for TI-SC heterostructures should be highly resilient against external contamination and structurally compatible with TIs. In this study, we provide a solution to this challenge by showcasing the growth of a highly crystalline TI-SC heterostructure using refractory TiN (111) as the superconducting layer. This approach can eliminate the need for in situ cleavage or growth. More importantly, the TiN surface shows high resilience against contaminations during air exposure, as demonstrated by the successful recyclable growth of Bi2Se3. Our findings indicate that TI-SC heterostructures based on nitride films are compatible with device fabrication techniques, paving the way to the realization of practical topological qubit devices in the future.

4.
Org Lett ; 26(23): 5021-5026, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38842216

RESUMO

We describe a simple and robust oxidation strategy for preparing N-terminal thiazolidine-containing peptide thioesters from peptide hydrazides. We find for the first time that l-thioproline can be used as a protective agent to prevent the nitrosation of N-terminal thiazolidine during peptide hydrazide oxidation. The thioproline-based oxidation strategy has been successfully applied to the chemical synthesis of CC chemokine ligand-2 (69aa) and omniligase-C (113aa), thereby demonstrating its utility in hydrazide-based native chemical ligation.


Assuntos
Oxirredução , Peptídeos , Tiazolidinas , Tiazolidinas/química , Tiazolidinas/síntese química , Estrutura Molecular , Peptídeos/química , Peptídeos/síntese química , Hidrazinas/química , Prolina/química , Ésteres/química , Compostos de Sulfidrila/química
6.
Front Cardiovasc Med ; 11: 1364332, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38707890

RESUMO

Background: Postoperative acute kidney injury (PO-AKI) is a prevalent complication among patients with acute type A aortic dissection (aTAAD) for which unrecognized trajectories of renal function recovery, and their heterogeneity, may underpin poor success in identifying effective therapies. Methods: This was a retrospective, single-center cohort study in a regional Great Vessel Center including patients undergoing aortic dissection surgery. Estimated glomerular filtration rate (eGFR) recovery trajectories of PO-AKI were defined through the unsupervised latent class mixture modeling (LCMM), with an assessment of patient and procedural characteristics, complications, and early-term survival. Internal validation was performed by resampling. Results: A total of 1,295 aTAAD patients underwent surgery and 645 (49.8%) developed PO-AKI. Among the PO-AKI cohort, the LCMM identified two distinct eGFR trajectories: early recovery (ER-AKI, 51.8% of patients) and late or no recovery (LNR-AKI, 48.2% of patients). Binary logistic regression identified five critical determinants regarding poor renal recovery, including chronic kidney disease (CKD) history, renal hypoperfusion, circulation arrest time, intraoperative urine, and myoglobin. LNR-AKI was associated with increased mortality, continuous renal replacement therapies, mechanical ventilation, ICU stay, and hospital stay. The assessment of the predictive model was good, with an area under the curve (AUC) of 0.73 (95% CI: 0.69-0.76), sensitivity of 61.74%, and specificity of 75.15%. The internal validation derived a consistent average AUC of 0.73. The nomogram was constructed for clinicians' convenience. Conclusion: Our study explored the PO-AKI recovery patterns among surgical aTAAD patients and identified critical determinants that help to predict individuals at risk of poor recovery of renal function.

7.
ACS Biomater Sci Eng ; 10(6): 3883-3895, 2024 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-38700993

RESUMO

Periodontitis is a chronic disease caused by bacterial infection and is characterized with alveolar bone resorption. Bone regeneration in periodontitis remains a critical challenge because bacterial infection induced an unfavorable microenvironment for osteogenesis. Therefore, it is necessary to design proper therapeutic platforms to control bacterial infection and promote bone regeneration. Herein, mesoporous bioactive glass (MBG) with different pore sizes (3.0, 4.3, and 12.3 nm) was used as an in situ reactor to confine the growth of gold nanoparticles (Au NPs), forming MBG@Au hybrids which combine the osteoconductivity of MBG and antibacterial properties of Au NPs. Upon near-infrared (NIR) irradiation, the MBG@Au NPs showed efficient antibacterial properties both in vitro and in vivo. Besides, the osteogenesis properties of MBG@Au also improved under NIR irradiation. Furthermore, the in vivo results demonstrated that MBG@Au can effectively promote alveolar bone regeneration and realize the healing of serious periodontitis.


Assuntos
Antibacterianos , Regeneração Óssea , Vidro , Ouro , Nanopartículas Metálicas , Periodontite , Periodontite/tratamento farmacológico , Nanopartículas Metálicas/química , Nanopartículas Metálicas/uso terapêutico , Ouro/química , Ouro/farmacologia , Ouro/uso terapêutico , Animais , Porosidade , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Antibacterianos/química , Regeneração Óssea/efeitos dos fármacos , Vidro/química , Camundongos , Osteogênese/efeitos dos fármacos , Masculino , Porphyromonas gingivalis/efeitos dos fármacos , Humanos
8.
J Cancer Res Clin Oncol ; 150(5): 254, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38748373

RESUMO

OBJECTIVE: The aim of this study is to conduct a systematic evaluation of the diagnostic efficacy of Breast Imaging Reporting and Data System (BI-RADS) 4 benign and malignant breast lesions using magnetic resonance imaging (MRI) radiomics. METHODS: A systematic search identified relevant studies. Eligible studies were screened, assessed for quality, and analyzed for diagnostic accuracy. Subgroup and sensitivity analyses explored heterogeneity, while publication bias, clinical relevance and threshold effect were evaluated. RESULTS: This study analyzed a total of 11 studies involving 1,915 lesions in 1,893 patients with BI-RADS 4 classification. The results showed that the combined sensitivity and specificity of MRI radiomics for diagnosing BI-RADS 4 lesions were 0.88 (95% CI 0.83-0.92) and 0.79 (95% CI 0.72-0.84). The positive likelihood ratio (PLR), negative likelihood ratio (NLR), and diagnostic odds ratio (DOR) were 4.2 (95% CI 3.1-5.7), 0.15 (95% CI: 0.10-0.22), and 29.0 (95% CI 15-55). The summary receiver operating characteristic (SROC) analysis yielded an area under the curve (AUC) of 0.90 (95% CI 0.87-0.92), indicating good diagnostic performance. The study found no significant threshold effect or publication bias, and heterogeneity among studies was attributed to various factors like feature selection algorithm, radiomics algorithms, etc. Overall, the results suggest that MRI radiomics has the potential to improve the diagnostic accuracy of BI-RADS 4 lesions and enhance patient outcomes. CONCLUSION: MRI-based radiomics is highly effective in diagnosing BI-RADS 4 benign and malignant breast lesions, enabling improving patients' medical outcomes and quality of life.


Assuntos
Neoplasias da Mama , Imageamento por Ressonância Magnética , Humanos , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/patologia , Imageamento por Ressonância Magnética/métodos , Feminino , Sensibilidade e Especificidade , Mama/diagnóstico por imagem , Mama/patologia , Radiômica
9.
Angew Chem Int Ed Engl ; : e202402915, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38569128

RESUMO

Sustainable carbon dots based on cellulose, particularly carboxymethyl cellulose carbon dots (CMCCDs), were confined in an inorganic network resulting in CMCCDs@SiO2. This resulted in a material exhibiting long afterglow covering a time frame of several seconds also under air. Temperature-dependent emission spectra gave information on thermally activated delayed fluorescence (TADF) and room temperature phosphorescence (RTP) while photocurrent experiments provided a deeper understanding of charge availability in the dark period, and therefore, its availability on the photocatalyst surface. The photo-ATRP initiator, ethyl α-bromophenylacetate (EBPA), quenched the emission from the millisecond to the nanosecond time frame indicating participation of the triplet state in photoinduced electron transfer (PET). Both free radical and controlled radical polymerization based on photo-ATRP protocol worked successfully. Metal-free photo-ATRP resulted in chain extendable macroinitiators based on a reductive mechanism with either MMA or in combination with styrene. Addition of 9 ppm Cu2+ resulted in Mw/Mn of 1.4 while an increase to 72 ppm improved uniformity of the polymers; that is Mw/Mn=1.03. Complementary experiments with kerria laca carbon dots confined materials, namely KCDs@SiO2, provided similar results. Deposition of Cu2+ (9 ppm) on the photocatalyst surface explains better uniformity of the polymers formed in the ATRP protocol.

10.
J Contin Educ Nurs ; 55(7): 359-364, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38567920

RESUMO

BACKGROUND: This study investigated the impact of applying the anchored teaching mode with nursing interns on the cardiac surgery intensive care unit (CSICU). METHOD: A total of 110 interns were divided into a control group (taught through traditional methods) and an experimental group (taught using the anchored teaching mode). The anchored mode, emphasizing student-centered learning, included creating scenarios, identifying problems, using self-directed and collaborative learning, and evaluating outcomes. RESULTS: Our study found that the experimental group showed significantly higher scores in emergency response ability, nursing skills, and teaching effectiveness compared with the control group at graduation. CONCLUSION: The findings suggest that implementing the anchored teaching mode can effectively enhance the education of nursing interns on the CSICU, emphasizing the need for further research across different departments and types of hospitals. [J Contin Educ Nurs. 2024;55(7):359-364.].


Assuntos
Enfermagem de Cuidados Críticos , Humanos , Masculino , Feminino , Adulto , Enfermagem de Cuidados Críticos/educação , Procedimentos Cirúrgicos Cardíacos/educação , Unidades de Terapia Intensiva , Currículo , Educação Continuada em Enfermagem/organização & administração , Competência Clínica , Recursos Humanos de Enfermagem Hospitalar/educação
11.
Angew Chem Int Ed Engl ; 63(24): e202401943, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38594205

RESUMO

Electrochemical C-N coupling reaction based on carbon dioxide and nitrate have been emerged as a new "green synthetic strategy" for the synthesis of urea, but the catalytic efficiency is seriously restricted by the inherent scaling relations of adsorption energies of the active sites, the improvement of catalytic activity is frequently accompanied by the decrease in selectivity. Herein, a doping engineering strategy was proposed to break the scaling relationship of intermediate binding and minimize the kinetic barrier of C-N coupling. A thus designed SrCo0.39Ru0.61O3-δ catalyst achieves a urea yield rate of 1522 µg h-1 mgcat. -1 and faradic efficiency of 34.1 % at -0.7 V versus reversible hydrogen electrode. A series of characterizations revealed that Co doping not only induces lattice distortion but also creates rich oxygen vacancies (OV) in the SrRuO3. The oxygen vacancies weaken the adsorption of *CO and *NH2 intermediates on the Co and Ru sites respectively, and the strain effects over the Co-Ru dual sites promoting the occurrence of C-N coupling of the two monomers instead of selective hydrogenating to form by-products. This work presents an insight into molecular coupling reactions towards urea synthesis via the doping engineering on SrRuO3.

12.
Regen Ther ; 27: 112-119, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38550913

RESUMO

The use of stem cell-based treatment systems is prevalent in regenerative medicine. To enhance the regenerative capabilities of stem cells, growth factors are typically incorporated into the treatment system. Nonetheless, traditional hydrogel-encapsulated or heparinized scaffolds that bind factors have limitations. In this study, we prepared a biomaterial strategy using uniform poly(lactic-co-glycolic) acid (PLGA) microspheres (uPLGA-Ms) fabricated by microfluidic to sustain delivery of insulin-like growth factor 1 (IGF-1), a critical protein for hMSCs biological functions. The uPLGA-Ms loaded IGF-1 were highly monodispersed through precise manipulation of the flow rate of the two-phase of the flow-focusing microchannle. The results showed that the uPLGA-Ms stabilize IGF-1 and provide a more efficient sustained delivery and cost-effective of growth factor. Gene expression analysis demonstrated the uPLGA delivery of IGF-1 results in a (enhanced) supported hMSCs expansion, survival, stemness, and secretion abilities comparable with the conventional soluble IGF-1 group. In summary, this material-based strategy to stabilize and sustain delivery of growth factor has broad potential to regeneration of various tissues and organs.

13.
Pak J Med Sci ; 40(4): 747-752, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38544986

RESUMO

Objective: To explore the effects of clinical nursing pathway (CNP) on the postoperative satisfaction and quality of life (QOL) of patients with subarachnoid hemorrhage (SAH). Methods: This is a retrospective study. Eighty patients with SAH admitted to Baoding No.1 Central Hospital from June 2021 to January 2023 were prospectively divided into a observation group and a control group by random numbers. The control group was given routine nursing, and the observation group was additional given CNP. The prognosis, cognitive function, QOL, self-care ability, nursing satisfaction and the incidence of complications were compared between the two groups. Results: After CNP nursing, the GCS and MMSE scores in the observation group were higher than those in the control group 14 days, one month and six months after the operation; and the difference was statistically significant (p< 0.05). Six months after the operation, the SS-QOL and Ability of daily living (ADL) scores in both groups were significantly improved compared with those before the intervention; and the improvement in the observation group was significantly better than that in the control group; and the difference was statistically significant(p<0.05). The nursing satisfaction score in the observation group was significantly higher than in the control group. The total incidence of complications in the observation group was lower than that in the control group. Conclusions: The CNP intervention in perioperative period of SAH patients has remarkable clinical effect, can improve the pertinence and efficiency of nursing, promote patients to recover as soon as possible, significantly improve the QOL of patients,and is worthy of clinical popularization.

14.
Org Lett ; 26(13): 2601-2605, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38529932

RESUMO

We report here an enzymatic strategy for asparaginyl endopeptidase-mediated peptide cyclization. Incorporation of chloroacetyl groups into the recognition sequence of OaAEP1 enabled intramolecular cyclization with Cys residues. Combining this strategy and phage display, we identified nanomolar macrocyclic peptide ligands targeting TEAD4. One of the bicyclic peptides binds to TEAD4 with a KD value of 139 nM, 16 times lower than its linear analogue, demonstrating the utility of this platform in discovering high-affinity macrocyclic peptide ligands.


Assuntos
Bacteriófagos , Peptídeos , Ciclização , Peptídeos/química , Cisteína Endopeptidases , Ligantes , Bacteriófagos/metabolismo , Biblioteca de Peptídeos , Peptídeos Cíclicos/química
15.
EJNMMI Res ; 14(1): 21, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38409511

RESUMO

BACKGROUND: 18F-FDG positron emission tomography (PET) plays a crucial part in the evaluation for pediatric epileptic patients prior to therapy. Short-term scanning holds significant importance, especially for pediatrics epileptic individuals who exhibited involuntary movements. The aim was to evaluate the effects of short acquisition time on image quality and lesion detectability in pediatric epileptic patients using total-body (TB) PET/CT. A total of 25 pediatric patients who underwent TB PET/CT using uEXPLORER scanner with an 18F-FDG administered dose of 3.7 MBq/kg and an acquisition time of 600 s were retrospectively enrolled. Short acquisition times (60 s, 150 and 300 s) were simulated by truncating PET data in list mode to reduce count density. Subjective image quality was scored on a 5-point scale. Regions of interest analysis of suspected epileptogenic zones (EZs), corresponding locations contralateral to EZs, and healthy cerebellar cortex were used to compare the semi-quantitative uptake indices of short-time images and then were compared with 600 s images. The comparison of EZs detectability based on time-dependent PET images was performed. RESULTS: Our study demonstrated that a short acquisition time of 150 s is sufficient to maintain subjective image quality and lesion significance. Statistical analysis revealed no significant difference in subjective PET image quality between imaging at 300 s and 150 s (P > 0.05). The overall impression scores of image quality and lesion conspicuity in G60s were both greater than 3 (overall quality, 3.21 ± 0.46; lesion conspicuity, 4.08 ± 0.74). As acquisition time decreased, the changes of SUVmax and SD in the cerebellar cortex gradually increased (P < 0.01). There was no significant difference in asymmetry index (AI) difference between the groups and the AIs of EZs were > 15% in all groups. In 26 EZs of 25 patients, the lesion detection rate was still 100% when the time was reduced to 60 s. CONCLUSIONS: This study proposed that TB PET/CT acquisition time could be reduced to 60 s with acceptable lesion detectability. Furthermore, it was suggested that a 150 s acquisition time would be sufficient to achieve diagnostic performance and image quality for children with epilepsy.

17.
J Imaging Inform Med ; 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38424277

RESUMO

This study aims to develop an MRI-based radiomics model to assess the likelihood of recurrence in luminal B breast cancer. The study analyzed medical images and clinical data from 244 patients with luminal B breast cancer. Of 244 patients, 35 had experienced recurrence and 209 had not. The patients were randomly divided into the training set (51.5 ± 12.5 years old; n = 171) and the test set (51.7 ± 11.3 years old; n = 73) in a ratio of 7:3. The study employed univariate and multivariate Cox regression along with the least absolute shrinkage and selection operator (LASSO) regression methods to select radiomics features and calculate a risk score. A combined model was constructed by integrating the risk score with the clinical and pathological characteristics. The study identified two radiomics features (GLSZM and GLRLM) from DCE-MRI that were used to calculate a risk score. The AUCs were 0.860 and 0.868 in the training set and 0.816 and 0.714 in the testing set for 3- and 5-year recurrence risk, respectively. The combined model incorporating the risk score, pN, and endocrine therapy showed improved predictive power, with AUCs of 0.857 and 0.912 in the training set and 0.943 and 0.945 in the testing set for 3- and 5-year recurrence risk, respectively. The calibration curve of the combined model showed good consistency between predicted and measured values. Our study developed an MRI-based radiomics model that integrates clinical and radiomics features to assess the likelihood of recurrence in luminal B breast cancer. The model shows promise for improving clinical risk stratification and treatment decision-making.

18.
J Colloid Interface Sci ; 660: 147-156, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38241863

RESUMO

Carbon dots (CDs) exhibit distinctive optical, electronic, and physicochemical properties, rendering them effective cocatalysts to enhance the photocatalytic performance of light-absorbing materials. The interplay between CDs and substrates is pivotal in manipulating photogenerated charge separation, transfer, and redistribution, significantly influencing overall photocatalytic efficiency. This study introduces a novel electrostatic interaction strategy to interface positively charged CdS nanorods (CdS NRs) with negatively charged furfural-derived CDs. The resulting optimized composite (25-CDs@CdS NRs), showcases photocatalytic hydrogen production at a rate of 1076 µmol g-1h-1. Experimental analyses and theoretical simulations offer insights into the structure-activity relationship, underscoring the crucial role of enhanced electrostatic interaction between CDs and CdS NRs in facilitating efficient charge transfer, activating reaction sites, and improving reaction kinetics. This research establishes an adaptable strategy for integrating CDs with metal-based semiconductors, opening new avenues for developing photocatalytic hybrid assemblies.

19.
Adv Mater ; 36(11): e2307661, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37994613

RESUMO

Pt-based fuel cell catalysts with excellent activity and stability for proton-exchange membrane fuel cells (PEMFCs) have been developed through strain regulation in recent years. Herein, this work demonstrates that symmetry-induced strain regulation of Pt surface of PtGa intermetallic compounds can greatly enhance the catalytic performance of the oxygen reduction reaction (ORR). With the strain environment varies derived from the lattice mismatch of analogous PtGa core but different symmetry, the Pt surface of the PtGa alloy and the Pt3 Ga (Pm 3 ¯ $\bar{3}$ m) precisely realize 0.58% and 2.7% compressive strain compared to the Pt3 Ga (P4/mmm). Experimental and theoretical results reveal that when the compressive stress of the Pt lattice increases, the desorption process of O* intermediates becomes accelerated, which is conducive to oxygen reduction. The Pt3 Ga (Pm 3 ¯ $\bar{3}$ m) with high symmetry and compressive Pt surface exhibit the highest mass and specific activities of 2.18 A mgPt -1 and 5.36 mA cm-2 , respectively, which are more than one order of magnitude higher than those of commercial Pt/C catalysts. This work demonstrates that material symmetry can be used to precisely modulate Pt surface stress to enhance the ORR, as well as provide a distinct platform to investigate the relationship between Pt compressibility and catalytic activity.

20.
J Nanobiotechnology ; 21(1): 499, 2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-38129881

RESUMO

Using a magnetic resonance imaging (MRI) contrast agent, MRI has made substantial contributions to glioma diagnosis. Metal-free MRI agents, such as the nano free radical nitric oxide (NO·) micelle, can overcome the inherent toxicity of metal-based agents in certain patient populations. However, the low spatial resolution of nano NO· micelle in MRI limits its clinical development. In this study, we pretreated platelets (PLTs) and loaded them with nano NO· micelles to synthesize NO·@PLT, which can overcome the low contrast and poor in vivo stability of nitroxide-based MRI contrast agents. The PLTs can serve as potential drug carriers for targeting and delivering nano NO· micelles to gliomas and thus increase the contrast in T1-weighted imaging (T1WI) of MRI. This drug carrier system uses the unique tumor-targeting ability of PLTs and takes advantage of the high signal presentation of steady nano NO· micelles in T1WI, thereby ultimately achieving signal amplification of glioma in T1WI. With the effect of PLTs-tumor cell adhesion, NO·@PLT has per-nitroxide transverse relativities of approximately 2-fold greater than those of free NO· particles. These features allow a sufficient NO·@PLT concentration to accumulate in murine subcutaneous glioma tumors up from 5 min to 2.5 h (optimum at 1.5 h) after systemic administration. This results in MRI contrast comparable to that of metal-based agents. This study established a promising metal-free MRI contrast agent, NO·@PLT, for glioma diagnosis, because it has superior spatial resolution owing to its high glioma-targeting ability and has significant translational implications in the clinic.


Assuntos
Meios de Contraste , Glioma , Humanos , Camundongos , Animais , Micelas , Óxido Nítrico/uso terapêutico , Glioma/diagnóstico por imagem , Glioma/tratamento farmacológico , Imageamento por Ressonância Magnética , Portadores de Fármacos/uso terapêutico , Linhagem Celular Tumoral
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA