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Nephritis is an inflammatory condition of the glomerulus, and the clinical gold standard for its diagnosis is a kidney biopsy. However, obtaining biopsy results can take several days, which does not meet the requirement of rapid diagnosis, especially for rapidly progressive types. To achieve an effective and noninvasive diagnosis, we propose a nephritis-specific, positive magnetic resonance imaging (MRI) contrast agent based on Gd3+ anchored walking dead macrophage Gd-RAW. Gd-RAW exhibits high selectivity for inflammatory renal parenchyma and provides comparable results to histopathology methods. The Gd-RAW-based MRI contrast agent reduces the diagnostic time of nephritis from 14 days of biopsy to 1 h. Furthermore, in a unilateral nephritis model constructed by increasing the glycerol concentration, the T1WI of renal parenchyma exhibits an increased signal-to-noise ratio, which is crucial for evaluating nephritic severity. This work promotes rapid diagnosis of nephritis and potentially provides sufficient evidence for clinicians to offer timely treatment to patients. The methodology of paramagnetic ion-anchored macrophage corpse also opens up new prospects for designing more specific and biosafe MRI contrast agents.
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Meios de Contraste , Nefrite , Humanos , Rim/diagnóstico por imagem , Nefrite/diagnóstico por imagem , Glomérulos Renais , Imageamento por Ressonância Magnética/métodosRESUMO
Magnetic resonance imaging (MRI) is an important tool in the diagnosis of many cancers. However, clinical gadolinium (Gd)-based MRI contrast agents have limitations, such as large doses and potential side effects. To address these issues, we developed a hydrogen-bonded organic framework-based MRI contrast agent (PFC-73-Mn). Due to the hydrogen-bonded interaction of water molecules and the restricted rotation of manganese ions, PFC-73-Mn exhibits high longitudinal relaxation r1 (5.03 mM-1 s-1) under a 3.0 T clinical MRI scanner. A smaller intravenous dose (8 µmol of Mn/kg) of PFC-73-Mn can provide strong contrast and accurate diagnosis in multiple kinds of cancers, including breast tumor and ultrasmall orthotopic glioma. PFC-73-Mn represents a prospective new approach in tumor imaging, especially in early-stage cancer.
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Glioma , Manganês , Humanos , Meios de Contraste , Gadolínio , Imageamento por Ressonância Magnética/métodosRESUMO
Patients with triple-negative breast cancer (TNBC) have dismal prognoses due to the lack of therapeutic targets and susceptibility to lymph node (LN) metastasis. Therefore, it is essential to develop more effective approaches to identify early TNBC tissues and LNs. In this work, a magnetic resonance imaging (MRI) contrast agent (Mn-iCOF) was constructed based on the Mn(II)-chelated ionic covalent organic framework (iCOF). Because of the porous structure and hydrophilicity, the Mn-iCOF has a high longitudinal relaxivity (r1) of 8.02 mM-1 s-1 at 3.0 T. For the tumor-bearing mice, a lower dose (0.02 mmol [Mn]/kg) of Mn-iCOF demonstrated a higher signal-to-noise ratio (SNR) value (1.8) and longer retention time (2 h) compared to a 10-fold dose of commercial Gd-DOTA (0.2 mmol [Gd]/kg). Moreover, the Mn-iCOF can provide continuous and significant MR contrast for the popliteal LNs within 24 h, allowing for accurate evaluation and dissection of LNs. These excellent MRI properties of the Mn-iCOF may open new avenues for designing more biocompatible MRI contrast agents with higher resolutions, particularly in the diagnosis of TNBC.
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Estruturas Metalorgânicas , Neoplasias de Mama Triplo Negativas , Humanos , Camundongos , Animais , Estruturas Metalorgânicas/química , Neoplasias de Mama Triplo Negativas/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Meios de Contraste/química , Espectroscopia de Ressonância MagnéticaRESUMO
BACKGROUND: The T2* value of interventricular septum is routinely reported for grading myocardial iron load in thalassemia major, and automatic segmentation of septum could shorten analysis time and reduce interobserver variability. PURPOSE: To develop a deep learning-based method for automatic septum segmentation from black-blood MR images for the myocardial T2* measurement of thalassemia patients. STUDY TYPE: Retrospective. POPULATION/SUBJECTS: One hundred forty-six transfusion-dependent thalassemia patients with cardiac MR examinations from two centers. Data from Center 1 (1.5 T) were assigned to the training (100 examinations) and internal testing (20 examinations) sets; data from Center 2 were assigned to the external testing set (26 examinations; 10 at 1.5 T and 16 at 3.0 T). FIELD STRENGTH/SEQUENCE: 1.5 T and 3.0 T, multiecho gradient-echo sequence. ASSESSMENT: A modified attention U-Net for septum segmentation was constructed and trained, and its performance evaluated on unseen internal and external datasets. T2* was measured by fitting the average septum signal, separately segmented by automatic and manual methods. STATISTICAL TESTS: Agreement between manual and automatic septum segmentations was assessed with the Dice coefficient, and T2* agreement was assessed using the Bland-Altman plot and the coefficient of variation (CoV). RESULTS: The median Dice coefficient of deep network-based septum segmentation was 0.90 [0.05] on the internal dataset, 0.82 [0.10] on the external 1.5 T dataset, and 0.86 [0.14] on the external 3.0 T dataset. T2* measurements using automatic segmentation corresponded with those from manual segmentation, with a mean difference of 0.02 (95% LoA: -0.74 to 0.79) msec, 0.43 (95% LoA: -2.1 to 3.0) msec, and 0.36 (95% LoA: -0.72 to 1.4) msec on the three datasets. The CoVs between the two methods were 3.1%, 7.0%, and 6.1% on the internal and two external datasets, respectively. DATA CONCLUSIONS: The proposed septum segmentation yielded myocardial T2* measurements which were highly consistent with those obtained by manual segmentation. This automatic approach may facilitate data processing and avoid operator-dependent variability in practice. EVIDENCE LEVEL: 4 TECHNICAL EFFICACY: Stage 1.
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Brain glucose is an important biomarker of Alzheimer's disease (AD) and has a high specificity especially for early AD. Activatable magnetic resonance imaging (MRI) contrast agents (CAs) serve as a robust technology in the early diagnosis of many diseases; however, there is a lack of glucose-specific MRI CAs. To address this issue, in this work, we synthesized a novel MRI CA (ZIF-8/GOx@MnO2@PEG, ZGMP) that consists of porous zeolitic imidazolate framework-8 (ZIF-8) attached with glucose oxidase (GOx) and modified by MnO2 and PEG. The cascade reaction of brain glucose with ZGMP could result in the production of Mn(II) and an enhanced MRI signal. An early AD mouse model was constructed through injection of the Aß42 oligomer into the parenchyma of mice and utilized to verify the brain glucose activated MRI of ZGMP. The results indicated a higher glucose uptake in early AD mice compared to that in normal mice, with an obviously enhanced T1WI at the region of interest. This work gets rid of the need for a specific scanning sequence for glucose MRI, paving a convenient way for MRI diagnosis of early AD.
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Doença de Alzheimer , Zeolitas , Humanos , Doença de Alzheimer/diagnóstico por imagem , Meios de Contraste , Glucose , Compostos de Manganês , Óxidos , Imageamento por Ressonância Magnética/métodos , Encéfalo/diagnóstico por imagem , Diagnóstico Precoce , Glucose OxidaseRESUMO
BACKGROUND: As a secreted adipokine, adipsin has been recently shown to play a pivotal role in metabolic disorders. However, information regarding the association of circulating adipsin with non-alcoholic fatty liver disease (NAFLD) in humans is scant. METHODS: We recruited 1163 obese adult subjects with waist circumference at least 90 cm in men and 80 cm in women from the community. Circulating adipsin levels were measured by enzyme-linked immunosorbent assay. RESULTS: Circulating adipsin levels of NAFLD subjects was decreased compared to those in non-NAFLD (p < 0.05). The prevalence of NAFLD with lower levels of serum adipsin was significantly higher than those with higher values (57.6% vs. 50.9%, p < 0.05). Circulating adipsin levels were significantly associated with decreasing levels of fasting glucose and postprandial glucose (both p < 0.001 for interaction) in NAFLD subjects but not in non-NAFLD subjects. The risk of NAFLD was significantly decreased by 21.7% [OR (95% CI): 0.783 (0.679-0.902), p < 0.001], adjusting for age, gender, current smoking, alcohol consumption, physical activity, BMI, systolic BP, fasting glucose, total cholesterol, HDL-c, HOMA-IR, and body fat mass. Importantly, subjects in the lowest quartile of circulating adipsin were 1.88 times more likely to have NAFLD than those in the highest quartile in multivariable logistic regression analyses. However, such associations with circulating adipsin were not noted for metabolic syndrome, abnormal liver enzyme and significant liver fibrosis. CONCLUSIONS: These results demonstrate that circulating adipsin levels in Chinese obese adults are negatively associated with risk of NAFLD, implying that serum adipsin levels may be a potential protective factor in NAFLD.
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Hepatopatia Gordurosa não Alcoólica , Adulto , Índice de Massa Corporal , Fator D do Complemento , Estudos Transversais , Feminino , Humanos , Masculino , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Obesidade/complicações , Obesidade/epidemiologia , Fatores de Risco , Circunferência da CinturaRESUMO
PURPOSE: To develop a fully automatic parenchyma extraction method for the T2* relaxometry of iron overload liver. METHODS: A retrospective multicenter collection of liver MR examinations from 177 transfusion-dependent patients was conducted. The proposed method extended a semiautomatic parenchyma extraction algorithm to a fully automatic approach by introducing a modified TransUNet on the R2* (1/T2*) map for liver segmentation. Axial liver slices from 129 patients at 1.5 T were allocated to training (85%) and internal test (15%) sets. Two external test sets separately included 1.5 T data from 20 patients and 3.0 T data from 28 patients. The final T2* measurement was obtained by fitting the average signal of the extracted liver parenchyma. The agreement between T2* measurements using fully and semiautomatic parenchyma extraction methods was assessed using coefficient of variation (CoV) and Bland-Altman plots. RESULTS: Dice of the deep network-based liver segmentation was 0.970 ± 0.019 on the internal dataset, 0.960 ± 0.035 on the external 1.5 T dataset, and 0.958 ± 0.014 on the external 3.0 T dataset. The mean difference bias between T2* measurements of the fully and semiautomatic methods were separately 0.12 (95% CI: -0.37, 0.61) ms, 0.04 (95% CI: -1.0, 1.1) ms, and 0.01 (95% CI: -0.25, 0.23) ms on the three test datasets. The CoVs between the two methods were 4.2%, 4.8% and 2.0% on the internal test set and two external test sets. CONCLUSIONS: The developed fully automatic parenchyma extraction approach provides an efficient and operator-independent T2* measurement for assessing hepatic iron content in clinical practice.
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Sobrecarga de Ferro , Ferro , Humanos , Reprodutibilidade dos Testes , Fígado/diagnóstico por imagem , Sobrecarga de Ferro/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodosRESUMO
The contribution of urban non-point source (NPS) pollution to surface water pollution has gradually increased, analyzing the sources of urban NPS pollution is of great significance for precisely controlling surface water pollution. A bibliometric analysis of relevant research literature from 2000 to 2021 reveals that the main methods used in the source analysis research of urban NPS pollution include the emission inventory approach, entry-exit mass balance approach, principal component analysis (PCA), positive matrix factorization (PMF) model, etc. These methods are primarily applied in three aspects: source analysis of rainfall-runoff pollution, source analysis of wet weather flow (WWF) pollution in combined sewers, and analysis of the contribution of urban NPS to the surface water pollution load. The application of source analysis methods in urban NPS pollution research has demonstrated an evolution from qualitative to quantitative, and further towards precise quantification. This progression has transitioned from predominantly relying on on-site monitoring to incorporating model simulations and employing mathematical statistical analyses for traceability. This paper reviews the principles, advantages, disadvantages, and the scope of application of these methods. It also aims to address existing problems and analyze potential future development directions, providing valuable references for subsequent related research.
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Poluição Difusa , Poluentes Químicos da Água , Poluição Difusa/análise , Monitoramento Ambiental/métodos , Poluição da Água/análise , Tempo (Meteorologia) , China , Poluentes Químicos da Água/análiseRESUMO
The migration of polluting enterprises (MPE) is a crucial subject within the fields of Environmental Economic Geography and Enterprise Geography. An analysis was conducted on the temporal-spatial evolution and influencing factors of the MPE by employing the full-sample enterprises data from the "Qichacha" system. The main findings were obtained: (1) The polluting enterprises in the Yangtze River Delta have undergone an evolutionary process of proximity migration, intra-provincial proximity to intra-provincial long distance migration, with intra-provincial migration being the main focus supplemented by inter-provincial migration, and coexisting intra-provincial and inter-provincial migration. (2) The estimation results, based on the panel negative-binomial model, reveal that the variables having a greater impact on the MPE encompass environmental regulation, industrial upgrading policies, cost factors, geographical distance, coastal and inter-provincial boundaries, etc. These influencing factors display time heterogeneity and industry heterogeneity. (3) By taking the Nijiaxiang Group, which was involved in the 321 Explosion Accident in Xiangshui, as an example, it was discovered that insufficient inheritance of environmental protection concepts, corruption of officials, and social governance problems have resulted in shortcomings in the area. This has led to a lowered level of local environmental regulation, transforming the local area into a haven for polluting enterprises such as the Nijiaxiang Group. The contribution of this study lies in observing the MPE from the perspective of "inter-regional association," and within the group enterprises. It addresses the deficiencies of existing research that mainly examines the evolution of industrial geographic patterns and statically observes polluting enterprises' entry and exit behavior. Moreover, this study demonstrates that the Pollution Shelter Hypothesis is not universal and has an impact in the Yangtze River Delta region after 2012.
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Objective: Neuronavigation and classification of craniopharyngiomas can guide surgical approaches and prognostic information. The QST classification has been developed according to the origin of craniopharyngiomas; however, accurate preoperative automatic segmentation and the QST classification remain challenging. This study aimed to establish a method to automatically segment multiple structures in MRIs, detect craniopharyngiomas, and design a deep learning model and a diagnostic scale for automatic QST preoperative classification. Methods: We trained a deep learning network based on sagittal MRI to automatically segment six tissues, including tumors, pituitary gland, sphenoid sinus, brain, superior saddle cistern, and lateral ventricle. A deep learning model with multiple inputs was designed to perform preoperative QST classification. A scale was constructed by screening the images. Results: The results were calculated based on the fivefold cross-validation method. A total of 133 patients with craniopharyngioma were included, of whom 29 (21.8%) were diagnosed with type Q, 22 (16.5%) with type S and 82 (61.7%) with type T. The automatic segmentation model achieved a tumor segmentation Dice coefficient of 0.951 and a mean tissue segmentation Dice coefficient of 0.8668 for all classes. The automatic classification model and clinical scale achieved accuracies of 0.9098 and 0.8647, respectively, in predicting the QST classification. Conclusions: The automatic segmentation model can perform accurate multi-structure segmentation based on MRI, which is conducive to clearing tumor location and initiating intraoperative neuronavigation. The proposed automatic classification model and clinical scale based on automatic segmentation results achieve high accuracy in the QST classification, which is conducive to developing surgical plans and predicting patient prognosis.
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Importance: The efficacy and safety of time-restricted eating (TRE) on nonalcoholic fatty liver disease (NAFLD) remain uncertain. Objective: To compare the effects of TRE vs daily calorie restriction (DCR) on intrahepatic triglyceride (IHTG) content and metabolic risk factors among patients with obesity and NAFLD. Design, Setting, and Participants: This 12-month randomized clinical trial including participants with obesity and NAFLD was conducted at the Nanfang Hospital in Guangzhou, China, between April 9, 2019, and August 28, 2021. Interventions: Participants with obesity and NAFLD were randomly assigned to TRE (eating only between 8:00 am and 4:00 pm) or DCR (habitual meal timing). All participants were instructed to maintain a diet of 1500 to 1800 kcal/d for men and 1200 to 1500 kcal/d for women for 12 months. Main Outcomes and Measures: The primary outcome was change in IHTG content measured by magnetic resonance imaging; secondary outcomes were changes in body weight, waist circumference, body fat, and metabolic risk factors. Intention-to-treat analysis was used. Results: A total of 88 eligible patients with obesity and NAFLD (mean [SD] age, 32.0 [9.5] years; 49 men [56%]; and mean [SD] body mass index, 32.2 [3.3]) were randomly assigned to the TRE (n = 45) or DCR (n = 43) group. The IHTG content was reduced by 8.3% (95% CI, -10.0% to -6.6%) in the TRE group and 8.1% (95% CI, -9.8% to -6.4%) in the DCR group at the 6-month assessment. The IHTG content was reduced by 6.9% (95% CI, -8.8% to -5.1%) in the TRE group and 7.9% (95% CI, -9.7% to -6.2%) in the DCR group at the 12-month assessment. Changes in IHTG content were comparable between the 2 groups at 6 months (percentage point difference: -0.2; 95% CI, -2.7 to 2.2; P = .86) and 12 months (percentage point difference: 1.0; 95% CI, -1.6 to 3.5; P = .45). In addition, liver stiffness, body weight, and metabolic risk factors were significantly and comparably reduced in both groups. Conclusions and Relevance: Among adults with obesity and NAFLD, TRE did not produce additional benefits for reducing IHTG content, body fat, and metabolic risk factors compared with DCR. These findings support the importance of caloric intake restriction when adhering to a regimen of TRE for the management of NAFLD. Trial Registration: ClinicalTrials.gov Identifiers: NCT03786523 and NCT04988230.
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Hepatopatia Gordurosa não Alcoólica , Adulto , Masculino , Humanos , Feminino , Hepatopatia Gordurosa não Alcoólica/complicações , Obesidade/complicações , Obesidade/metabolismo , Fatores de Risco , Triglicerídeos/metabolismo , Tecido AdiposoRESUMO
Background The association between menstrual cycle characteristics and cardiovascular outcomes remains unclear. This study was undertaken to evaluate whether menstrual cycle regularity and length throughout the life course are associated with cardiovascular outcomes. Methods and Results This cohort study included 58 056 women who had no cardiovascular disease (CVD) at baseline and reported their menstrual cycle regularity and length. Hazard ratios (HRs) and 95% CIs for CVD events were estimated using Cox proportional hazards models. During the median 11.8 years of follow-up, 1623 incident CVD cases were documented, including 827 incident cases of coronary heart disease, 199 myocardial infarctions, 271 strokes, 174 cases of heart failure, and 393 cases of atrial fibrillations. Compared with women with regular menstrual cycles, the HRs for women with irregular menstrual cycles were 1.19 (95% CI, 1.07-1.31) for CVD events and 1.40 (95% CI, 1.14-1.72) for atrial fibrillation. The multivariable-adjusted HRs for short (≤21 days) or long (35 days) menstrual cycles during follow-up were 1.29 (95% CI, 1.11-1.50) and 1.11 (95% CI, 0.98-1.56) for CVD events, respectively. Similarly, long or short cycle length were more likely to be associated with increased risk of atrial fibrillation (HR, 1.30 [95% CI, 1.01-1.66]; and HR, 1.38 [95% CI, 1.02-1.87]), and short cycle length was more likely to be associated with increased risk of coronary heart disease and myocardial infarction. However, these associations for stroke and heart failure were not significant. Conclusions Long or short menstrual cycle length was associated with increased risks of CVD and atrial fibrillation but not myocardial infarction, heart failure, or stroke. Short cycle length was associated with a greater risk of coronary heart disease and myocardial infarction.
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Fibrilação Atrial , Doenças Cardiovasculares , Doença das Coronárias , Insuficiência Cardíaca , Infarto do Miocárdio , Acidente Vascular Cerebral , Humanos , Feminino , Estudos Prospectivos , Estudos de Coortes , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/epidemiologia , Fibrilação Atrial/complicações , Bancos de Espécimes Biológicos , Fatores de Risco , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/complicações , Infarto do Miocárdio/epidemiologia , Infarto do Miocárdio/complicações , Insuficiência Cardíaca/epidemiologia , Insuficiência Cardíaca/complicações , Doença das Coronárias/epidemiologia , Doença das Coronárias/complicações , Acidente Vascular Cerebral/etiologia , Ciclo Menstrual , Reino Unido/epidemiologiaRESUMO
Embolization (utilizing embolic materials to block blood vessels) has been considered one of the most promising strategies for clinical disease treatments. However, the existing embolic materials have poor embolization effectiveness, posing a great challenge to highly efficient embolization. In this study, we construct Janus particle-engineered structural lipiodol droplets by programming the self-assembly of Janus particles at the lipiodol-water interface. As a result, we achieve highly efficient renal embolization in rabbits. The obtained structural lipiodol droplets exhibit excellent mechanical stability and viscoelasticity, enabling them to closely pack together to efficiently embolize the feeding artery. They also feature good viscoelastic deformation capacities and can travel distally to embolize finer vasculatures down to 40 µm. After 14 days post-embolization, the Janus particle-engineered structural lipiodol droplets achieve efficient embolization without evidence of recanalization or non-target embolization, exhibiting embolization effectiveness superior to the clinical lipiodol-based emulsion. Our strategy provides an alternative approach to large-scale fabricate embolic materials for highly efficient embolization and exhibits good potential for clinical applications.
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Óleo Etiodado , Nanopartículas Multifuncionais , Animais , Coelhos , Artérias , Bandagens , RimRESUMO
Over most of the last two decades, China's Outward Direct Investment (CODI) has reshaped the global economic landscape and attracted considerable attention. Although extensive research shows that CODI features agglomeration, there is limited research from the perspective of different patterns of agglomeration economies at the subnational level. It is unclear which patterns of agglomeration economies play a role in the location choice of CODI, especially with the variations of CODI in terms of entry mode and ownership. Therefore, based on the data of the CODI in the United States in the period 2000-2016, we use a conditional logit model to investigate the influence of specialized and diversified agglomeration of local firms as well as industry-specific and industry-diverse agglomeration of Chinese investors on the location choice of CODI, and further explore the heterogeneous influence concerning the entry mode and ownership. Our results show that among a variety of agglomeration economies, the specialized agglomeration of local firms is the premier factor influencing the location choice of CODI, even exceeding the influence of industry-specific agglomeration of CODI in the same industry. Industry-diverse agglomeration of CODI plays a weak role, while diversified agglomeration of local firms has no effect. Moreover, the location choice of acquisition is more sensitive to the specialized agglomeration of local firms than that of greenfield investment, and the influence of the industry-diverse agglomeration of CODI has no effect on the location choice of acquisition. In terms of the ownership, the location choice of state-owned enterprises (SOEs) is more sensitive to the specialized agglomeration of local firms and industry-specific agglomeration of CODI than that of private investment, and the industry-diverse agglomeration of CODI has no significant impact on the location choice of SOEs' offshoring subsidiaries.
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Indústrias , Investimentos em Saúde , China , Propriedade , Estados UnidosRESUMO
Immunogenic cell death (ICD) has aroused widespread attention because it can reconstruct a tumor microenvironment and activate antitumor immunity. This study proposes a two-way enhancement of ICD based on a CaO2 @CuS-MnO2 @HA (CCMH) nanocomposite to overcome the insufficient damage-associated molecular patterns (DAMPs) of conventional ICD-inducers. The near-infrared (NIR) irradiation (1064 nm) of CuS nanoparticles generates 1 O2 through photodynamic therapy (PDT) to trigger ICD, and it also damages the Ca2+ buffer function of mitochondria. Additionally, CaO2 nanoparticles react with H2 O to produce a large amount of O2 and Ca2+ , which respectively lead to enhanced PDT and Ca2+ overload during mitochondrial damage, thereby triggering a robust ICD activation. Moreover, oxidative-damaged mitochondrial DNA, induced by PDT and released from tumor cells, reprograms the immunosuppressive tumor microenvironment by transforming tumor-associated macrophages to the M1 subphenotype. This study shows that CCMH with NIR-II irradiation can elicit adequate DAMPs and an active tumor-immune microenvironment for both 4T1 and CT26 tumor models. Combining this method with an immune checkpoint blockade can realize an improved immunotherapy efficacy and long-term protection effect for body.
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Nanopartículas , Neoplasias , Fotoquimioterapia , Humanos , Fotoquimioterapia/métodos , Macrófagos Associados a Tumor , Morte Celular Imunogênica , Compostos de Manganês , Óxidos/farmacologia , Neoplasias/terapia , Imunoterapia/métodos , Microambiente Tumoral , Linhagem Celular TumoralRESUMO
A major impediment in the development of nanoplatform-based ovarian cancer therapy is endo/lysosome entrapment. To solve this dilemma, a hollow mesoporous organosilica-based nanoplatform (HMON@CuS/Gd2O3) with a mild-temperature photothermal therapeutic effect and multimodal imaging abilities was successfully synthesized. HMON@CuS/Gd2O3 exhibited an appropriate size distribution, L-glutathione (GSH)-responsive degradable properties, and high singlet oxygen generation characteristics. In this study, the nanoplatform specifically entered SKOV-3 cells and was entrapped in endo/lysosomes. With a mild near infrared (NIR) power density (.5 W/cm2), the HMON@CuS/Gd2O3 nanoplatform caused lysosome vacuolation, disrupted the lysosomal membrane integrity, and exerted antitumour effects in ovarian cancer. Additionally, our in vivo experiments indicated that HMON@CuS/Gd2O3 has enhanced T1 MR imaging, fluorescence (FL) imaging (wrapping fluorescent agent), and infrared thermal (IRT) imaging capacities. Using FL/MRI/IRT imaging, HMON@CuS/Gd2O3 selectively caused mild phototherapy in the cancer region, efficiently inhibiting the growth of ovarian cancer without systemic toxicity in vivo. Taken together, the results showed that these well-synthesized nanoplatforms are likely promising anticancer agents to treat ovarian cancer and show great potential for biomedical applications.
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Endossomos/efeitos dos fármacos , Compostos de Organossilício/química , Neoplasias Ovarianas/patologia , Fototerapia/métodos , Nanomedicina Teranóstica/métodos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Química Farmacêutica , Feminino , Humanos , Concentração de Íons de Hidrogênio , Imagem Multimodal , Propriedades de SuperfícieRESUMO
The formimidoyltransferase cyclodeaminase (FTCD) gene encodes an enzyme required for the catabolism of histidine and tetrahydrofolate (THF). Previous studies showed that FTCD plays a role as a tumour suppressor gene in hepatocellular carcinoma (HCC). It is unknown whether the restoration of functional FTCD may exhibit an anti-tumour effect on HCC. This study constructed a delivery system based on hollow mesoporous organosilica nanotheranostics (HMON) capable of efficiently loading Mn ions and FTCD plasmids. This study showed that the Mn-doped and FTCD-loaded nanoparticles (HMON@Mn-PEI@FTCD) could efficiently induce the expression of FTCD and achieve enhanced magnetic resonance imaging. In vitro results demonstrated that the upregulation of FTCD induced by HMON@Mn-PEI@FTCD nanoparticles dramatically reduced intracellular THF levels, inhibited of NADPH/NADP+ and GSH/GSSG ratios, and induced reactive oxygen species generation and mitochondrial oxidative stress. As a result, cytochrome c release increased with the opening of the mitochondrial permeability transition pore, which finally activated the caspase-dependent cell apoptosis pathway. Therefore, our designed HMON@Mn-PEI@FTCD could induce apoptosis by activating the mitochondria-mediated apoptosis signalling pathway, and finally significantly suppressed the proliferation of HCC both in vitro and in vivo, which provides an effective strategy for the treatment of HCC.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Apoptose , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/tratamento farmacológico , Linhagem Celular Tumoral , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/tratamento farmacológico , Imageamento por Ressonância Magnética , Plasmídeos , Tetra-Hidrofolatos , Nanomedicina TeranósticaRESUMO
The imaging resolution of magnetic resonance imaging (MRI) is influenced by many factors. The development of more effective MRI contrast agents (CAs) is significant for early tumor detection and radical treatment, albeit challenging. In this work, the Hofmeister effect of Fe2O3 nanoparticles within the tumor microenvironment was confirmed for the first time. Based on this discovery, we designed a nanocomposite (FePN) by loading Fe2O3 nanoparticles on black phosphorus nanosheets. After reacting with glutathione, the FePN will undergo two stages in the tumor microenvironment, resulting in the robust enhancement of r1 and r2 based on the Hofmeister effect in the commonly used magnetic field (3.0 T). The glutathione-activated MRI signal of FePN was higher than most of the activatable MRI CAs, enabling a more robust visualization of tumors. Furthermore, benefiting from the long circulation time of FePN in the blood and retention time in tumors, the synergistic therapy of FePN exhibited an outstanding inhibition toward tumors. The FePN with good biosafety and biocompatibility will not only pave a new way for designing a common magnetic field-tailored T1-T2 dual-mode MRI CA but also offer a novel pattern for the accurate clinical diagnosis and therapy of tumors.
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INTRODUCTION: Integrin α6 is an attractive diagnostic biomarker for molecular imaging of hepatocellular carcinoma (HCC) as it has an extremely high positive rate (approximately 94%) in clinical early-stage HCC. In this study, based on our previously identified integrin α6-targeted peptide, we developed an optimized integrin α6-targeted magnetic resonance (MR) probe dubbed DOTA(Gd)-ANADYWR for MR imaging of HCC in mice. MATERIALS AND METHODS: The longitudinal (R1) relaxivity of DOTA(Gd)-ANADYWR was measured on a 3.0 T MR system . The specific tumor enhancement of the agent was investigated in four distinct mouse models, including subcutaneous, orthotopic, genetically engineered and chemically induced HCC mice. RESULTS: The R1 relaxivity value of DOTA(Gd)-ANADYWR is 5.11 mM-1s-1 at 3.0 T, which is similar to that of the nonspecific clinical agent Gadoteridol. DOTA(Gd)-ANADYWR generated superior enhanced MR signal in HCC lesions and provided complementary enhancement MR signals to the clinically available hepatobiliary MR contrast agent gadoxetate disodium (Gd-EOB-DTPA). Importantly, DOTA(Gd)-ANADYWR could efficiently visualize small HCC lesion (approximately 1 mm) which was hardly detected by the clinical Gd-EOB-DTPA. CONCLUSION: These findings suggest the potential application of this integrin α6-targeted MR probe for the detection of HCC, particularly for small HCC.
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INTRODUCTION: The aims of the study were to summarize the characteristics of the spinal epidural cavernous hemangioma, especially for the MRI, and to improve the accurate rate of the preoperative diagnosis. METHODS: The clinical and medical imaging data of six patients with pure spinal epidural cavernous hemangioma proved by operation and pathology were analyzed retrospectively. RESULTS: The level was thoracic (n = 2), thoracolumbar (n = 1), lumbar (n = 1), and sacral (n = 2). The tumor showed lobulated contour, and the areas the tumors appeared were dorsal side of spinal cord (n = 2), ventral side (n = 1), and lateral side (n = 3). In all six patients, the lesions were isointense to the spinal cord on T(1)-weighted images and hyperintense on T(2)-weighted images and showed homogeneously strong enhancement on contrast-enhanced T(1)-weighted images. The characteristic MRI features were named as the "wafting-silk" sign. Widening of the intervertebral neural foramen (n = 4) and erosion of the adjacent bones (n = 3) can be observed. CONCLUSIONS: MRI of the epidural cavernous hemangioma showed the characteristic lobulated contour, which encircled the spinal cord. T(1)WI on the MRI presented as isointense and T(2)WI presented as hyperintense and a homogeneously strong enhancement, so we first proposed the sign of wafting silk. The widening of the intervertebral neural foramen and erosion of the adjacent bones can easily be observed. MR imaging has an important role in the detection and diagnosis of pure spinal epidural cavernous hemangioma.