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1.
Small ; 20(14): e2308547, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37988646

RESUMO

Magnetic resonance imaging contrast agents are frequently used in clinics to enhance the contrast between diseased and normal tissues. The previously reported poly(acrylic acid) stabilized exceedingly small gadolinium oxide nanoparticles (ES-GdON-PAA) overcame the problems of commercial Gd chelates, but limitations still exist, i.e., high r2/r1 ratio, long blood circulation half-life, and no data for large scale synthesis and formulation optimization. In this study, polymaleic acid (PMA) is found to be an ideal stabilizer to synthesize ES-GdONs. Compared with ES-GdON-PAA, the PMA-stabilized ES-GdON (ES-GdON-PMA) has a lower r2/r1 ratio (2.05, 7.0 T) and a lower blood circulation half-life (37.51 min). The optimized ES-GdON-PMA-9 has an exceedingly small particle size (2.1 nm), excellent water dispersibility, and stability. A facile, efficient, and environmental friendly synthetic method is developed for large-scale synthesis of the ES-GdONs-PMA. The weight of the optimized freeze-dried ES-GdON-PMA-26 synthesized in a 20 L of reactor reaches the kilogram level. The formulation optimization is also finished, and the concentrated ES-GdON-PMA-26 formulation (CGd = 100 mm) after high-pressure steam sterilization possesses eligible physicochemical properties (i.e., pH value, osmolality, viscosity, and density) for investigational new drug application.


Assuntos
Meios de Contraste , Nanopartículas , Meios de Contraste/química , Imageamento por Ressonância Magnética/métodos , Gadolínio/química , Nanopartículas/química
2.
Small ; 20(29): e2309842, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38431935

RESUMO

Triple negative breast cancer (TNBC) cells have a high demand for oxygen and glucose to fuel their growth and spread, shaping the tumor microenvironment (TME) that can lead to a weakened immune system by hypoxia and increased risk of metastasis. To disrupt this vicious circle and improve cancer therapeutic efficacy, a strategy is proposed with the synergy of ferroptosis, immunosuppression reversal and disulfidptosis. An intelligent nanomedicine GOx-IA@HMON@IO is successfully developed to realize this strategy. The Fe release behaviors indicate the glutathione (GSH)-responsive degradation of HMON. The results of titanium sulfate assay, electron spin resonance (ESR) spectra, 5,5'-Dithiobis-(2-nitrobenzoic acid (DTNB) assay and T1-weighted magnetic resonance imaging (MRI) demonstrate the mechanism of the intelligent iron atom (IA)-based cascade reactions for GOx-IA@HMON@IO, generating robust reactive oxygen species (ROS). The results on cells and mice reinforce the synergistic mechanisms of ferroptosis, immunosuppression reversal and disulfidptosis triggered by the GOx-IA@HMON@IO with the following steps: 1) GSH peroxidase 4 (GPX4) depletion by disulfidptosis; 2) IA-based cascade reactions; 3) tumor hypoxia reversal; 4) immunosuppression reversal; 5) GPX4 depletion by immunotherapy. Based on the synergistic mechanisms of ferroptosis, immunosuppression reversal and disulfidptosis, the intelligent nanomedicine GOx-IA@HMON@IO can be used for MRI-guided tumor therapy with excellent biocompatibility and safety.


Assuntos
Ferroptose , Imageamento por Ressonância Magnética , Ferroptose/efeitos dos fármacos , Imageamento por Ressonância Magnética/métodos , Animais , Humanos , Linhagem Celular Tumoral , Camundongos , Espécies Reativas de Oxigênio/metabolismo , Terapia de Imunossupressão , Microambiente Tumoral/efeitos dos fármacos , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/patologia , Neoplasias de Mama Triplo Negativas/diagnóstico por imagem , Feminino , Glutationa/metabolismo
3.
J Nanobiotechnology ; 22(1): 234, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38724978

RESUMO

Radiotherapy-induced immune activation holds great promise for optimizing cancer treatment efficacy. Here, we describe a clinically used radiosensitizer hafnium oxide (HfO2) that was core coated with a MnO2 shell followed by a glucose oxidase (GOx) doping nanoplatform (HfO2@MnO2@GOx, HMG) to trigger ferroptosis adjuvant effects by glutathione depletion and reactive oxygen species production. This ferroptosis cascade potentiation further sensitized radiotherapy by enhancing DNA damage in 4T1 breast cancer tumor cells. The combination of HMG nanoparticles and radiotherapy effectively activated the damaged DNA and Mn2+-mediated cGAS-STING immune pathway in vitro and in vivo. This process had significant inhibitory effects on cancer progression and initiating an anticancer systemic immune response to prevent distant tumor recurrence and achieve long-lasting tumor suppression of both primary and distant tumors. Furthermore, the as-prepared HMG nanoparticles "turned on" spectral computed tomography (CT)/magnetic resonance dual-modality imaging signals, and demonstrated favorable contrast enhancement capabilities activated by under the GSH tumor microenvironment. This result highlighted the potential of nanoparticles as a theranostic nanoplatform for achieving molecular imaging guided tumor radiotherapy sensitization induced by synergistic immunotherapy.


Assuntos
Ferroptose , Imunoterapia , Compostos de Manganês , Proteínas de Membrana , Camundongos Endogâmicos BALB C , Nanopartículas , Nucleotidiltransferases , Óxidos , Radiossensibilizantes , Animais , Camundongos , Imunoterapia/métodos , Óxidos/química , Óxidos/farmacologia , Feminino , Nucleotidiltransferases/metabolismo , Compostos de Manganês/química , Compostos de Manganês/farmacologia , Linhagem Celular Tumoral , Nanopartículas/química , Radiossensibilizantes/farmacologia , Radiossensibilizantes/química , Proteínas de Membrana/metabolismo , Ferroptose/efeitos dos fármacos , Glucose Oxidase/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Humanos , Dano ao DNA , Microambiente Tumoral/efeitos dos fármacos
4.
J Nanobiotechnology ; 22(1): 162, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38594700

RESUMO

To overcome the problems of commercial magnetic resonance imaging (MRI) contrast agents (CAs) (i.e., small molecule Gd chelates), we have proposed a new concept of Gd macrochelates based on the coordination of Gd3+ and macromolecules, e.g., poly(acrylic acid) (PAA). To further decrease the r2/r1 ratio of the reported Gd macrochelates that is an important factor for T1 imaging, in this study, a superior macromolecule hydrolyzed polymaleic anhydride (HPMA) was found to coordinate Gd3+. The synthesis conditions were optimized and the generated Gd-HPMA macrochelate was systematically characterized. The obtained Gd-HPMA29 synthesized in a 100 L of reactor has a r1 value of 16.35 mM-1 s-1 and r2/r1 ratio of 2.05 at 7.0 T, a high Gd yield of 92.7% and a high product weight (1074 g), which demonstrates the feasibility of kilogram scale facile synthesis. After optimization of excipients and sterilization at a high temperature, the obtained Gd-HPMA30 formulation has a pH value of 7.97, osmolality of 691 mOsmol/kg water, density of 1.145 g/mL, and viscosity of 2.2 cP at 20 â„ƒ or 1.8 cP at 37 â„ƒ, which meet all specifications and physicochemical criteria for clinical injections indicating the immense potential for clinical applications.


Assuntos
Meios de Contraste , Anidridos Maleicos , Metacrilatos , Polímeros , Meios de Contraste/química , Imageamento por Ressonância Magnética/métodos
5.
Eur Radiol ; 32(4): 2188-2199, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34842959

RESUMO

OBJECTIVES: An accurate and rapid diagnosis is crucial for the appropriate treatment of pulmonary tuberculosis (TB). This study aims to develop an artificial intelligence (AI)-based fully automated CT image analysis system for detection, diagnosis, and burden quantification of pulmonary TB. METHODS: From December 2007 to September 2020, 892 chest CT scans from pathogen-confirmed TB patients were retrospectively included. A deep learning-based cascading framework was connected to create a processing pipeline. For training and validation of the model, 1921 lesions were manually labeled, classified according to six categories of critical imaging features, and visually scored regarding lesion involvement as the ground truth. A "TB score" was calculated based on a network-activation map to quantitively assess the disease burden. Independent testing datasets from two additional hospitals (dataset 2, n = 99; dataset 3, n = 86) and the NIH TB Portals (n = 171) were used to externally validate the performance of the AI model. RESULTS: CT scans of 526 participants (mean age, 48.5 ± 16.5 years; 206 women) were analyzed. The lung lesion detection subsystem yielded a mean average precision of the validation cohort of 0.68. The overall classification accuracy of six pulmonary critical imaging findings indicative of TB of the independent datasets was 81.08-91.05%. A moderate to strong correlation was demonstrated between the AI model-quantified TB score and the radiologist-estimated CT score. CONCLUSIONS: The proposed end-to-end AI system based on chest CT can achieve human-level diagnostic performance for early detection and optimal clinical management of patients with pulmonary TB. KEY POINTS: • Deep learning allows automatic detection, diagnosis, and evaluation of pulmonary tuberculosis. • Artificial intelligence helps clinicians to assess patients with tuberculosis. • Pulmonary tuberculosis disease activity and treatment management can be improved.


Assuntos
Inteligência Artificial , Tuberculose Pulmonar , Adulto , Idoso , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Pessoa de Meia-Idade , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/métodos , Tuberculose Pulmonar/diagnóstico por imagem
6.
Eur J Nucl Med Mol Imaging ; 48(12): 3961-3974, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-33693966

RESUMO

INTRODUCTION: Lung cancer ranks second in new cancer cases and first in cancer-related deaths worldwide. Precision medicine is working on altering treatment approaches and improving outcomes in this patient population. Radiological images are a powerful non-invasive tool in the screening and diagnosis of early-stage lung cancer, treatment strategy support, prognosis assessment, and follow-up for advanced-stage lung cancer. Recently, radiological features have evolved from solely semantic to include (handcrafted and deep) radiomic features. Radiomics entails the extraction and analysis of quantitative features from medical images using mathematical and machine learning methods to explore possible ties with biology and clinical outcomes. METHODS: Here, we outline the latest applications of both structural and functional radiomics in detection, diagnosis, and prediction of pathology, gene mutation, treatment strategy, follow-up, treatment response evaluation, and prognosis in the field of lung cancer. CONCLUSION: The major drawbacks of radiomics are the lack of large datasets with high-quality data, standardization of methodology, the black-box nature of deep learning, and reproducibility. The prerequisite for the clinical implementation of radiomics is that these limitations are addressed. Future directions include a safer and more efficient model-training mode, merge multi-modality images, and combined multi-discipline or multi-omics to form "Medomics."


Assuntos
Neoplasias Pulmonares , Humanos , Pulmão , Neoplasias Pulmonares/diagnóstico por imagem , Aprendizado de Máquina , Prognóstico , Reprodutibilidade dos Testes
7.
Eur Respir J ; 56(2)2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32616597

RESUMO

BACKGROUND: The outbreak of coronavirus disease 2019 (COVID-19) has globally strained medical resources and caused significant mortality. OBJECTIVE: To develop and validate a machine-learning model based on clinical features for severity risk assessment and triage for COVID-19 patients at hospital admission. METHOD: 725 patients were used to train and validate the model. This included a retrospective cohort from Wuhan, China of 299 hospitalised COVID-19 patients from 23 December 2019 to 13 February 2020, and five cohorts with 426 patients from eight centres in China, Italy and Belgium from 20 February 2020 to 21 March 2020. The main outcome was the onset of severe or critical illness during hospitalisation. Model performances were quantified using the area under the receiver operating characteristic curve (AUC) and metrics derived from the confusion matrix. RESULTS: In the retrospective cohort, the median age was 50 years and 137 (45.8%) were male. In the five test cohorts, the median age was 62 years and 236 (55.4%) were male. The model was prospectively validated on five cohorts yielding AUCs ranging from 0.84 to 0.93, with accuracies ranging from 74.4% to 87.5%, sensitivities ranging from 75.0% to 96.9%, and specificities ranging from 55.0% to 88.0%, most of which performed better than the pneumonia severity index. The cut-off values of the low-, medium- and high-risk probabilities were 0.21 and 0.80. The online calculators can be found at www.covid19risk.ai. CONCLUSION: The machine-learning model, nomogram and online calculator might be useful to access the onset of severe and critical illness among COVID-19 patients and triage at hospital admission.


Assuntos
Infecções por Coronavirus/diagnóstico , Mortalidade Hospitalar/tendências , Aprendizado de Máquina , Pneumonia Viral/diagnóstico , Triagem/métodos , Adulto , Fatores Etários , Idoso , Área Sob a Curva , Bélgica , COVID-19 , Teste para COVID-19 , China , Técnicas de Laboratório Clínico , Estudos de Coortes , Infecções por Coronavirus/epidemiologia , Sistemas de Apoio a Decisões Clínicas , Feminino , Hospitalização/estatística & dados numéricos , Humanos , Internacionalidade , Itália , Masculino , Pessoa de Meia-Idade , Pandemias/estatística & dados numéricos , Pneumonia Viral/epidemiologia , Valor Preditivo dos Testes , Curva ROC , Reprodutibilidade dos Testes , Estudos Retrospectivos , Medição de Risco , Índice de Gravidade de Doença , Fatores Sexuais , Análise de Sobrevida
8.
Eur Radiol ; 29(10): 5358-5366, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30927099

RESUMO

OBJECTIVES: To evaluate the image quality of ultralow-dose computed tomography (ULDCT) reconstructed with knowledge-based iterative model reconstruction (IMR) in patients with pulmonary tuberculosis (TB). METHODS: This IRB-approved prospective study enrolled 59 consecutive patients (mean age, 43.9 ± 16.6 years; F:M 18:41) with known or suspected pulmonary TB. Patients underwent a low-dose CT (LDCT) using automatic tube current modulation followed by an ULDCT using fixed tube current. Raw image data were reconstructed with filtered-back projection (FBP), hybrid iterative reconstruction (iDose), and IMR. Objective measurements including CT attenuation, image noise, and contrast-to-noise ratio (CNR) were assessed and compared using repeated-measures analysis of variance. Overall image quality and visualization of normal and pathological findings were subjectively scored on a five-point scale. Radiation output and subjective scores were compared by the paired Student t test and Wilcoxon signed-rank test, respectively. RESULTS: Compared with FBP and iDose, IMR yielded significantly lower noise and higher CNR values at both dose levels (p < 0.01). Subjective ratings for pathological findings including centrilobular nodules, consolidation, tree-in-bud, and cavity were significantly better with ULDCT IMR images than those with LDCT iDose images (p < 0.01), but blurred edges were observed. With IMR implementation, a 59% reduction of the mean effective dose was achieved with ULDCT (0.28 ± 0.02 mSv) compared with LDCT (0.69 ± 0.15 mSv) without impairing image quality (p < 0.001). CONCLUSIONS: IMR offers considerable noise reduction and improvement in image quality for patients with pulmonary TB undergoing chest ULDCT at an effective dose of 0.28 mSv. KEY POINTS: • Radiation dose is a major concern for tuberculosis patients requiring repeated follow-up CT. • IMR allows substantial radiation dose reduction in chest CT without compromising image quality. • ULDCT reconstructed with IMR allows accurate depiction of CT features of pulmonary tuberculosis.


Assuntos
Tuberculose Pulmonar/diagnóstico por imagem , Adolescente , Adulto , Idoso , Algoritmos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada Multidetectores/métodos , Tomografia Computadorizada Multidetectores/normas , Estudos Prospectivos , Doses de Radiação , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Interpretação de Imagem Radiográfica Assistida por Computador/normas , Adulto Jovem
9.
Radiology ; 288(1): 285-292, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29634436

RESUMO

Purpose To compare the diagnostic quality of reduced radiation dose computed tomography (CT) with iterative model reconstruction (IMR) versus that of conventional low-dose CT in patients with pulmonary invasive fungal infection. Materials and Methods This prospective observational study included 48 patients (mean age ± standard deviation, 39.9 years ± 11.3) known to have or suspected of having pulmonary invasive fungal infection between October 2016 and July 2017. Patients underwent CT with IMR (at 80 kV with 20 mA) immediately after low-dose CT (at 80 kV with automatic exposure control). Images were reconstructed by using a hybrid iterative reconstruction (HIR) algorithm and IMR. Two radiologists independently assessed subjective image quality, noise, and visibility of normal and abnormal findings by using a five-point scale. Objective measurements, including image noise, contrast-to-noise ratio (CNR), and corresponding figure of merit (FOM), were compared by using repeated-measures analysis of variance with Bonferroni post hoc tests for multiple comparisons. Results The mean effective dose was 0.3 mSv ± 0.3 for CT with IMR and 0.7 mSv ± 0.2 for low-dose CT (P < .01). When the image noise and CNR were normalized to the effective dose, CT images obtained with IMR had significantly higher FOM than did other image series (P < .0001). Subjectively, visibility of CT features of invasive fungal infection on CT scans reconstructed with IMR was rated as noninferior to that on low-dose CT scans reconstructed with HIR, except for the halo sign. Conclusion CT with IMR had approximately 60% dose reduction compared with conventional low-dose CT, with reduced noise and improved depiction of abnormal findings, in patients with pulmonary invasive fungal infection.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Infecções Fúngicas Invasivas/diagnóstico por imagem , Pneumopatias Fúngicas/diagnóstico por imagem , Doses de Radiação , Tomografia Computadorizada por Raios X/métodos , Adulto , Feminino , Humanos , Pulmão/diagnóstico por imagem , Pulmão/microbiologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Reprodutibilidade dos Testes , Adulto Jovem
10.
Eur Radiol ; 27(1): 212-221, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27180185

RESUMO

OBJECTIVES: The purpose of this study was to determine whether intravoxel incoherent motion (IVIM) -derived parameters and apparent diffusion coefficient (ADC) could act as imaging biomarkers for predicting antifungal treatment response. METHODS: Forty-six consecutive patients (mean age, 33.9 ± 13.0 y) with newly diagnosed invasive fungal infection (IFI) in the lung according to EORTC/MSG criteria were prospectively enrolled. All patients underwent diffusion-weighted magnetic resonance (MR) imaging at 3.0 T using 11 b values (0-1000 sec/mm2). ADC, pseudodiffusion coffiecient D*, perfusion fraction f, and the diffusion coefficient D were compared between patients with favourable (n=32) and unfavourable response (n=14). RESULTS: f values were significantly lower in the unfavourable response group (12.6%±4.4%) than in the favourable response group (30.2%±8.6%) (Z=4.989, P<0.001). However, the ADC, D, and D* were not significantly different between the two groups (P>0.05). Receiver operating characteristic curve analyses showed f to be a significant predictor for differentiation, with a sensitivity of 93.8% and a specificity of 92.9%. CONCLUSIONS: IVIM-MRI is potentially useful in the prediction of antifungal treatment response to patients with IFI in the lung. Our results indicate that a low perfusion fraction f may be a noninvasive imaging biomarker for unfavourable response. KEY POINTS: • Recognition of IFI indicating clinical outcome is important for treatment decision-making. • IVIM can reflect diffusion and perfusion information of IFI lesions separately. • Perfusion characteristics of IFI lesions could help differentiate treatment response. • An initial low f may predict unfavourable response in IFI.


Assuntos
Antifúngicos/uso terapêutico , Infecções Fúngicas Invasivas/diagnóstico por imagem , Infecções Fúngicas Invasivas/tratamento farmacológico , Pneumopatias Fúngicas/diagnóstico por imagem , Adulto , Caspofungina , Imagem de Difusão por Ressonância Magnética/métodos , Equinocandinas/uso terapêutico , Feminino , Humanos , Interpretação de Imagem Assistida por Computador/métodos , Lipopeptídeos/uso terapêutico , Pneumopatias Fúngicas/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Movimento (Física) , Variações Dependentes do Observador , Prognóstico , Estudos Prospectivos , Curva ROC , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Resultado do Tratamento , Voriconazol/uso terapêutico , Adulto Jovem
11.
Med Sci Monit ; 22: 4438-4445, 2016 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-27864581

RESUMO

BACKGROUND The aim of this study was to investigate the potential value of apparent diffusion coefficient (ADC) of diffusion-weighted imaging (DWI) in the prognosis of patients with hyperacute cerebral infarction (HCI) receiving intravenous thrombolytic therapy with recombinant tissue plasminogen activator (rt-PA). MATERIAL AND METHODS From June 2012 to June 2015, 58 cases of HCI (<6 h) undergoing rt-PA intravenous thrombolytic therapy (thrombolysis group) and 70 cases of HCI (<6 h) undergoing conventional antiplatelet and anticoagulant therapy (control group) in the same period were collected. DWI was conducted on all the subjects, and ADC maps were generated with Functool software to quantify ADC value. The clinical outcomes of HCI patients were observed for 3 months, and prognostic factors were analyzed. RESULTS Before thrombolysis treatment, the lesion area presented high signal intensity on DWI map and low signal intensity on ADC map, and gradually weakened signal intensity on DWI map and gradually enhanced signal intensity on ADC map were observed after thrombolysis. The ADC values of the thrombolysis group were significantly higher than those of the control group after treatment (24 h, 7 d, 30 d, and 90 d) (all P<0.05), and the ADC and rADC values in the thrombolysis group gradually increased over time (all P<0.05). Multiple logistic regression analysis showed that baseline National Institutes of Health Stroke Scale (NIHSS) score, baseline rADC value, and stroke history were the independent factors for the prognosis of HIC patients with thrombolysis (all P<0.05). CONCLUSIONS The values of ADC and rADC may provide guidance in the prognosis of HCI patients receiving rt-PA, and the baseline rADC value is the protective factor for the prognosis of HCI patients receiving rt-PA.


Assuntos
Infarto Cerebral/diagnóstico por imagem , Infarto Cerebral/terapia , Terapia Trombolítica/métodos , Administração Intravenosa , Idoso , Estudos de Casos e Controles , Infarto Cerebral/patologia , Imagem de Difusão por Ressonância Magnética/métodos , Feminino , Fibrinolíticos/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Proteínas Recombinantes/uso terapêutico , Acidente Vascular Cerebral/tratamento farmacológico , Ativador de Plasminogênio Tecidual/uso terapêutico
12.
Eur Radiol ; 25(2): 550-7, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25231132

RESUMO

OBJECTIVES: To evaluate the diagnostic performance of five MR sequences to detect pulmonary infectious lesions in patients with invasive fungal infection (IFI), using multidetector computed tomography (MDCT) as the reference standard. METHODS: Thirty-four immunocompromised patients with suspected IFI underwent MDCT and MRI. The MR studies were performed using five pulse sequences at 3.0 T: T2-weighted turbo spin echo (TSE), short-tau inversion recovery (STIR), spectrally selective attenuated inversion recovery (SPAIR), T1-weighted high resolution isotropic volume excitation (e-THRIVE) and T1-weighted fast field echo (T1-FFE). The size, lesion-to-lung contrast ratio and the detectability of pulmonary lesions on MR images were assessed. Image quality and artefacts on different sequences were also rated. RESULTS: A total of 84 lesions including nodules (n = 44) and consolidation (n = 40) were present in 75 lobes. SPAIR and e-THRIVE images achieved high overall lesion-related sensitivities for the detection of pulmonary abnormalities (90.5% and 86.9%, respectively). STIR showed the highest lesion-to-lung contrast ratio for nodules (21.8) and consolidation (17.0), whereas TSE had the fewest physiological artefacts. CONCLUSIONS: MRI at 3.0 T can depict clinically significant pulmonary IFI abnormalities with high accuracy compared to MDCT. SPAIR and e-THRIVE are preferred sequences for the detection of infectious lesions of 5 mm and larger. KEY POINTS: • A radiation-free radiological method is desirable for assessing pulmonary infectious lesions • MRI at 3 T can depict lung infiltrates with good concordance to MDCT • SPAIR and e-THRIVE are favourable sequences for the detection of pulmonary lesions • The greatest benefit is for the diagnosis of lesions larger than 5 mm.


Assuntos
Pneumopatias Fúngicas/diagnóstico , Imageamento por Ressonância Magnética/métodos , Tomografia Computadorizada Multidetectores/métodos , Adolescente , Adulto , Artefatos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Curva ROC , Reprodutibilidade dos Testes , Estudos Retrospectivos , Adulto Jovem
13.
Adv Healthc Mater ; 13(14): e2303626, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38387885

RESUMO

Immunotherapy has emerged as an innovative strategy with the potential to improve outcomes in cancer patients. Recent evidence indicates that radiation-induced DNA damage can activate the cyclic-GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) pathway to enhance the antitumor immune response. Even so, only a small fraction of patients currently benefits from radioimmunotherapy due to the radioresistance and the inadequate activation of the cGAS-STING pathway. Herein, this work integrates hafnium oxide (HfO2) nanoparticles (radiosensitizer) and 7-Ethyl-10-hydroxycamptothecin (SN38, chemotherapy drug, STING agonist) into a polydopamine (PDA)-coated core-shell nanoplatform (HfO2@PDA/Fe/SN38) to achieve synergistic chemoradiotherapy and immunotherapy. The co-delivery of HfO2/SN38 greatly enhances radiotherapy efficacy by effectively activating the cGAS-STING pathway, which then triggers dendritic cells maturation and CD8+ T cells recruitment. Consequently, the growth of both primary and abscopal tumors in tumor-bearing mice is efficiently inhibited. Moreover, the HfO2@PDA/Fe/SN38 complexes exhibit favorable magnetic resonance imaging (MRI)/photoacoustic (PA) bimodal molecular imaging properties. In summary, these developed multifunctional complexes have the potential to intensify immune activation to realize simultaneous cancer Radio/Chemo/Immunotherapy for clinical translation.


Assuntos
Imunoterapia , Proteínas de Membrana , Nanopartículas , Nucleotidiltransferases , Animais , Nucleotidiltransferases/metabolismo , Proteínas de Membrana/metabolismo , Camundongos , Imunoterapia/métodos , Nanopartículas/química , Radiossensibilizantes/química , Radiossensibilizantes/farmacologia , Linhagem Celular Tumoral , Humanos , Camptotecina/farmacologia , Camptotecina/química , Camptotecina/análogos & derivados , Imagem Molecular/métodos , Polímeros/química , Neoplasias/terapia , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Transdução de Sinais/efeitos dos fármacos , Indóis/química , Indóis/farmacologia , Feminino
14.
Acad Radiol ; 31(7): 2962-2972, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38508939

RESUMO

RATIONALE AND OBJECTIVES: To evaluate the diagnostic performance of dual-energy CT (DECT) parameters and quantitative-semantic features for differentiating the invasiveness of lung adenocarcinoma manifesting as ground glass nodules (GGNs). MATERIALS AND METHODS: Between June 2022 and September 2023, 69 patients with 74 surgically resected GGNs who underwent DECT examinations were included. CT numbers on virtual monochromatic images were calculated at 40-130 keV generated from DECT. Quantitative morphological measurements and semantic features were evaluated on unenhanced CT images and compared between pathologically confirmed adenocarcinoma in situ (AIS)-minimally invasive adenocarcinoma (MIA) and invasive lung adenocarcinoma (IAC). Multivariable logistic regression analysis was used to identify independent predictors. The diagnostic performance was assessed by the area under the receiver operating characteristic curve (AUC) and compared using DeLong's test. RESULTS: Monochromatic CT numbers at 40-130 keV were significantly higher in IAC than in AIS-MIA (all P < 0.05). Multivariate logistic analysis revealed that CT number of 130 keV (odds ratio [OR] = 1.02, P = 0.013), maximum cross-sectional long diameter (OR =1.40, P = 0.014), deep or moderate lobulation sign (OR =19.88, P = 0.005), and abnormal intranodular vessel morphology (OR = 25.57, P = 0.017) were independent predictors of IAC. The combined prediction model showed a favorable differentiation performance with an AUC of 0.966 (95.2% sensitivity, 94.3% specificity, 94.8% accuracy), which was significantly higher than that for each risk factor (AUC = 0.791-0.822, all P < 0.05). CONCLUSION: A multi-parameter combined prediction model integrating monochromatic CT numbers from DECT and quantitative-semantic features is promising for the preoperative discrimination of IAC and AIS-MIA in GGN-predominant lung adenocarcinoma.


Assuntos
Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Invasividade Neoplásica , Tomografia Computadorizada por Raios X , Humanos , Feminino , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X/métodos , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/patologia , Idoso , Adenocarcinoma de Pulmão/diagnóstico por imagem , Adenocarcinoma de Pulmão/patologia , Diagnóstico Diferencial , Invasividade Neoplásica/diagnóstico por imagem , Estudos Retrospectivos , Adulto , Imagem Radiográfica a Partir de Emissão de Duplo Fóton/métodos , Idoso de 80 Anos ou mais , Sensibilidade e Especificidade
15.
Adv Mater ; 36(28): e2313212, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38670140

RESUMO

Cancer stem cells (CSCs) are one of the determinants of tumor heterogeneity and are characterized by self-renewal, high tumorigenicity, invasiveness, and resistance to various therapies. To overcome the resistance of traditional tumor therapies resulting from CSCs, a strategy of double drug sequential therapy (DDST) for CSC-enriched tumors is proposed in this study and is realized utilizing the developed double-layered hollow mesoporous cuprous oxide nanoparticles (DL-HMCONs). The high drug-loading contents of camptothecin (CPT) and all-trans retinoic acid (ATRA) demonstrate that the DL-HMCON can be used as a generic drug delivery system. ATRA and CPT can be sequentially loaded in and released from CPT3@ATRA3@DL-HMCON@HA. The DDST mechanisms of CPT3@ATRA3@DL-HMCON@HA for CSC-containing tumors are demonstrated as follows: 1) the first release of ATRA from the outer layer induces differentiation from CSCs with high drug resistance to non-CSCs with low drug resistance; 2) the second release of CPT from the inner layer causes apoptosis of non-CSCs; and 3) the third release of Cu+ from DL-HMCON itself triggers the Fenton-like reaction and glutathione depletion, resulting in ferroptosis of non-CSCs. This CPT3@ATRA3@DL-HMCON@HA is verified to possess high DDST efficacy for CSC-enriched tumors with high biosafety.


Assuntos
Camptotecina , Cobre , Células-Tronco Neoplásicas , Humanos , Porosidade , Camptotecina/química , Camptotecina/farmacologia , Animais , Cobre/química , Linhagem Celular Tumoral , Células-Tronco Neoplásicas/efeitos dos fármacos , Tretinoína/química , Tretinoína/farmacologia , Nanopartículas/química , Camundongos , Antineoplásicos/química , Antineoplásicos/farmacologia , Portadores de Fármacos/química , Apoptose/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Liberação Controlada de Fármacos
16.
Acta Biomater ; 2024 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-39004329

RESUMO

Calcium ions (Ca2+) participate in the regulation of cellular apoptosis as a second messenger. Calcium overload, which refers to the abnormal elevation of intracellular Ca2+ concentration, is a factor that can lead to cell death. Here, based on the unique biological effects of Ca2+, hollow mesoporous calcium peroxide nanoparticles (HMCPN) were developed by a facile hydrolysis-precipitation method for drug-free tumor calcicoptosis therapy. The average pore size of the optimized HMCPN17 is 6.4 nm, and the surface area is 81.3 m2/g, which enables HMCPN17 with high drug loading capability. The Ca2+ release from HMCPN17 is much faster at pH 6.8 than that at pH 7.4, which can be ascribed to the acid-triggered conversion of HMCPN17 to Ca2+ and H2O2, indicating a pH-responsive decomposition behavior of HMCPN17. The high drug loading contents of doxorubicin (DOX) and/or sorafenib (SFN) indicate that HMCPN17 can be employed as a generic drug delivery system (DDS). The in vitro and in vivo results reinforce the high calcicoptosis therapeutic efficacy of tumors by our HMCPN17 without drug loading, which can be attributed to the efficient accumulation in tumors and the ability of H2O2 and Ca2+ production at acidic TME. Our HMCPN17 has broad application prospect for construction of multi-drug-loaded composite nanomaterials with diversified functions for the treatment of tumors. STATEMENT OF SIGNIFICANCE: The combination of hollow mesoporous nanomaterials and calcium peroxide nanoparticles has a wide range of applications in the synergistic treatment of tumors. In this study, hollow mesoporous calcium peroxide nanoparticles (HMCPN) were developed based on a simple hydrolysis-precipitation method for tumor calcicoptosis therapy without drug loading. The high drug loading contents of DOX and/or SFN indicate that our HMCPN can serve as a generic DDS. The experimental results demonstrated the high calcicoptosis therapeutic efficacy of HMCPN on tumors even without drug loading.

17.
Biomaterials ; 311: 122701, 2024 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-38981152

RESUMO

Cuproptosis in antitumor therapy faces challenges from copper homeostasis efflux mechanisms and high glutathione (GSH) levels in tumor cells, hindering copper accumulation and treatment efficacy. Herein, we propose a strategy of "adding fuel to the flames" for potent antitumor therapy through a self-accelerating cycle of ferroptosis-cuproptosis. Disulfiram (DSF) loaded hollow mesoporous copper-iron sulfide (HMCIS) nanoparticle with conjugation of polyethylene glycol (PEG) and folic acid (FA) (i.e., DSF@HMCIS-PEG-FA) was developed to swiftly release DSF, H2S, Cu2+, and Fe2+ in the acidic tumor microenvironment (TME). The hydrogen peroxide (H2O2) levels and acidity within tumor cells enhanced by the released H2S induce acceleration of Fenton (Fe2+) and Fenton-like (Cu2+) reactions, enabling the powerful tumor ferroptosis efficacy. The released DSF acts as a role of "fuel", intensifying catalytic effect ("flame") in tumor cells through the sustainable Fenton chemistry (i.e., "add fuel to the flames"). Robust ferroptosis in tumor cells is characterized by serious mitochondrial damage and GSH depletion, leading to excess intracellular copper that triggers cuproptosis. Cuproptosis disrupts mitochondria, compromises iron-sulfur (Fe-S) proteins, and elevates intracellular oxidative stress by releasing free Fe3+. These interconnected processes form a self-accelerating cycle of ferroptosis-cuproptosis with potent antitumor capabilities, as validated in both cancer cells and tumor-bearing mice.

18.
Int J Dev Neurosci ; 83(1): 16-22, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36219509

RESUMO

This study aims to investigate the clinical prediction of magnetic resonance image compilation (MAGiC) and magnetic resonance image (MRI) in early diagnosis of the patients with mild cognitive impairment. This study is a retrospective randomized controlled clinical trial, and all patients are divided into following two groups: experiment group and control group. Patients in the experiment group are detected by MAGiC, and patients in the control group are detected by MRI; the clinical material from the two groups of patients with MCI are collected, and then Wechsler Memory Scale-Logical Memory (WMS-LM) and Mini-Mental State Examination (MMSE) are recorded by follow-up. Images by MAGiC have higher accuracy and definition compared with those by MRI. WMS-LM score and MMSE score in the experiment group are significantly better than those in the control group. We can conclude that MAGiC is a promising way to evaluate the clinical prediction in patients with MCI.


Assuntos
Disfunção Cognitiva , Humanos , Estudos Retrospectivos , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/patologia , Imageamento por Ressonância Magnética , Testes Neuropsicológicos
19.
Medicine (Baltimore) ; 102(37): e34979, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37713879

RESUMO

We aimed to investigate the role of combined apparent diffusion coefficient (ADC) values and relative cerebral blood flow (rCBF) values in the diagnosis of mild cognitive impairment (MCI) patients. The present prospective research enrolled 156 MCI patients and 58 healthy elderly people who came to our hospital from January 2021 to February 2023. T1W, T2W, diffusion-weighted imaging, and arterial spin labeling sequences were performed on all subjects, and ADC values and rCBF values were measured at the workstation. Clinical and demographic data of all patients were collected while mini-mental state examination (MMSE) and Montreal cognitive assessment (MoCA) scores were used to assess patients' cognitive abilities. The MCI group had significantly lower rCBF values in the left frontal lobe, left occipital lobe, right frontal lobe, and right occipital lobe than the HC group. The ADC values in the left frontal lobe as well as the right frontal lobe were remarkably elevated in the MCI group than in the HC group. MoCA and MMSE scores were positively correlated with rCBF values in the left frontal, right frontal, left occipital, and right occipital lobes and negatively correlated with ADC values in the left and right frontal lobes. Combined ADC values and rCBF values from the left frontal lobe for the diagnosis of MCI had a higher sensitivity and specificity with the AUC was 0.877, sensitivity 81.0%, specificity 82.7%. Additionally, pressure fasting plasma glucose, ADC of the left frontal lobe, right frontal lobe, rCBF of left frontal lobe and rCBF of left frontal lobe were the risk factors of patients with MCI. In summary, our results indicated that the ADC values and rCBF values were changed in MCI group compared to HC group and correlated with MMSE and MoCA scores.


Assuntos
Disfunção Cognitiva , Idoso , Humanos , Estudos Prospectivos , Disfunção Cognitiva/diagnóstico por imagem , Artérias , Circulação Cerebrovascular , Imagem de Difusão por Ressonância Magnética , Marcadores de Spin
20.
Bioeng Transl Med ; 8(1): e10364, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36684070

RESUMO

Cartilage regeneration after injury is still a great challenge in clinics, which suffers from its avascularity and poor proliferative ability. Herein we designed a novel biocompatible cellulose nanocrystal/GelMA (gelatin-methacrylate anhydride)/HAMA (hyaluronic acid-methacrylate anhydride)-blended hydrogel scaffold system, loaded with synthetic melanin nanoparticles (SMNP) and a bioactive drug kartogenin (KGN) for theranostic purpose. We found that the SMNP-KGN/Gel showed favorable mechanical property, thermal stability, and distinct magnetic resonance imaging (MRI) contrast enhancement. Meanwhile, the sustained release of KGN could recruit bone-derived mesenchymal stem cells to proliferate and differentiate into chondrocytes, which promoted cartilage regeneration in vitro and in vivo. The hydrogel degradation and cartilage restoration were simultaneously monitored by multiparametric MRI for 12 weeks, and further confirmed by histological analysis. Together, these results validated the multifunctional hydrogel as a promising tissue engineering platform for noninvasive imaging-guided precision therapy in cartilage regenerative medicine.

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