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1.
Eur Radiol ; 29(7): 3424-3430, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31062134

RESUMO

OBJECTIVE: To evaluate contrast-enhanced T1-weighted magnetic resonance (MR) images in histologically proven fibrous dysplasia (FD) for the prevalence of "milk cloud appearance" and its association with ground-glass appearance (GGA) on radiography or computed tomography (CT). METHODS: For this retrospective cohort study, 37 patients with histologically proven FD imaged preoperatively with contrast-enhanced MR imaging and radiography or CT were identified at our institution. Three radiologists independently evaluated MR images for the presence of milk cloud appearance on T1-weighted contrast-enhanced images, sites of skeletal involvement, type of bone involved, uni- vs. multifocality, mono- vs. polyostotic disease, maximum diameter, proportion of bone involved, expansile remodeling, and T2 homogeneity. The presence or absence of GGA on radiography or CT was determined in consensus. Inter-reader agreement was evaluated for milk cloud appearance using Cohen's kappa, and associations between milk cloud appearance and other imaging parameters were tested using Spearman's rho. RESULTS: Among the 37 histologically proven FD lesions, GGA was identified in 70% of the lesions, while milk cloud appearance was found in 82% of the lesions. Inter-reader agreement for milk cloud appearance on MR imaging was good to excellent (κ 0.65, 0.82, and 0.8). A significant correlation was found between milk cloud appearance and GGA (ρ = 0.31, p < 0.001). CONCLUSION: Milk cloud appearance is a characteristic sign of FD on contrast-enhanced T1-weighted MR images. Recognition of this feature may be helpful when radiographs are equivocal or unremarkable or when MR imaging is performed as the primary imaging modality in cases of FD. KEY POINTS: • Fibrous dysplasia displays a characteristic feature on contrast-enhanced T1-weighted MR imaging: milk cloud appearance. • Milk cloud appearance correlates well with the radiographic or CT finding of ground-glass appearance. • Recognition of milk cloud appearance on contrast-enhanced MR imaging may be helpful when radiographs are equivocal or unremarkable or when MR imaging is performed as the primary imaging modality in cases of fibrous dysplasia.


Assuntos
Osso e Ossos/patologia , Meios de Contraste/farmacologia , Displasia Fibrosa Óssea/diagnóstico , Imagem por Ressonância Magnética/métodos , Adolescente , Adulto , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
2.
Ultrasonics ; 98: 1-6, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31121515

RESUMO

The purpose of this work is to investigate whether imaging sequences of flash-replenishment contrast enhanced ultrasound (CEUS) of the kidney result in chronic or acute bioeffects. Kidneys of female Fischer 344 rats were imaged using the flash-replenishment technique. Animals were separated into four groups (N = 31). Imaging was conducted with a 4C1 probe, driven by an Acuson Sequoia system with Definity microbubbles as the ultrasound contrast agent. During the flash phase of the imaging sequence, one kidney in each animal was exposed to either a mechanical index (MI) of 1.0 or 1.9. For each MI, half of the animals were sacrificed shortly after imaging (4 h) or after 2 weeks. A blinded veterinary nephropathologist reviewed the histopathology of both the imaged and control (non-imaged) kidney. Blood urea nitrogen (BUN) was measured for each animal prior to imaging and at the time of necropsy. Histopathology assessments in both the 1.0 and 1.9 MI groups revealed no signs of hemorrhage at either the 4-h or 2-week time point. BUN showed minor but statistically significant elevations in both the 1.0 and 1.9 MI groups, but no significant difference was present at the 2-week time point in the 1.0 MI group. All BUN levels (at both time points) remained in the normal range. In conclusion, CEUS with flash-replenishment imaging sequences did not result in kidney bioeffects observable with histology at early or late time points. Increases in BUN levels were observed after imaging, but were minimized when using a moderate MI (1.0).


Assuntos
Análise Química do Sangue , Meios de Contraste/farmacologia , Fluorcarbonetos/farmacologia , Rim/efeitos dos fármacos , Rim/diagnóstico por imagem , Ultrassonografia , Animais , Nitrogênio da Ureia Sanguínea , Feminino , Microbolhas , Ratos , Ratos Endogâmicos F344
3.
Molecules ; 24(8)2019 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-30991689

RESUMO

We developed a tumor-targeted contrast agent based on linear polylysine (PLL) by conjugating a small molecular imaging agent, fluorescent molecule and targeting agent amino phenylboronic acid onto the amino groups of polylysine, which can specifically target monosaccharide sialic acid residues overexpressing on the surface of tumor cell membranes. Further, 3,4,5,6-Tetrahydrophthalic anhydride (DCA) was attached to the free amino groups of the polylysine to change to a negative charge at physiology pH to lower the cytotoxicity, but it soon regenerated to a positive charge again once reaching the acidic intratumoral environment and therefore increased cell uptake. Laser confocal microscopy images showed that most of the polymeric contrast agents were bound to the cancer cell membrane. Moreover, the tumor targeting contrast agent showed the same magnetic resonance imaging (MRI) contrasting performance in vitro as the small molecule contrast agent used in clinic, which made it a promising tumor-targeting polymeric contrast agent for cancer diagnosis.


Assuntos
Meios de Contraste , Imagem por Ressonância Magnética , Neoplasias/diagnóstico por imagem , Animais , Meios de Contraste/síntese química , Meios de Contraste/química , Meios de Contraste/farmacologia , Cães , Células Hep G2 , Humanos , Células Madin Darby de Rim Canino , Microscopia Confocal , Neoplasias/metabolismo , Neoplasias/patologia , Polilisina/síntese química , Polilisina/química , Polilisina/farmacologia
4.
Eur Radiol ; 29(7): 3772-3781, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30963274

RESUMO

OBJECTIVES: To differentiate between large (≥ 1 cm in diameter) gallbladder (GB) non-neoplastic and neoplastic polyps using quantitative analysis of contrast-enhanced ultrasound (CEUS) findings. METHODS: From September 2017 to May 2018, 29 patients (10 males; median age, 63 years) with GB polyps of ≥ 1 cm in diameter who were undergoing cholecystectomy were consecutively enrolled. All patients underwent preoperative conventional US and CEUS examinations. Quantitative analysis of CEUS findings using time-intensity curves between the two groups was independently performed by two radiologists. The interobserver agreement for the quantitative analysis of the CEUS results was measured using the intraclass correlation coefficient. Receiver operating characteristic analysis was performed to evaluate the diagnostic performance of CEUS examination. RESULTS: After the cholecystectomy, the patients were classified into the non-neoplastic polyp group (n = 12) and the neoplastic polyp group (n = 17) according to the pathological results. The interobserver agreement for quantitative assessment between the two radiologists was near perfect to substantial. Quantitative assessment of the CEUS findings revealed that the rise time, mean transit time, time to peak, and fall time of non-neoplastic GB polyps were significantly shorter than those of neoplastic polyps (p < 0.001, p = 0.008, p = 0.013, and p = 0.002, respectively). The sensitivity and specificity of the quantitative CEUS parameters for the differentiation between the two groups were 76.5-100% and 75%, respectively, with an area under the curve of 0.765-0.887. CONCLUSIONS: Quantitative analysis of CEUS findings could be valuable in differentiating GB neoplastic polyps from non-neoplastic polyps. KEY POINTS: • Quantitative analysis of CEUS findings could be valuable in differentiating gallbladder neoplastic polyps from non-neoplastic polyps. • Quantitative analysis of CEUS findings in gallbladder polyps provides cut-off values for differentiation between neoplastic polyps and non-neoplastic polyps with near-perfect to substantial interobserver agreement.


Assuntos
Meios de Contraste/farmacologia , Doenças da Vesícula Biliar/diagnóstico , Neoplasias da Vesícula Biliar/diagnóstico , Pólipos/diagnóstico , Ultrassonografia/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Colecistectomia , Diagnóstico Diferencial , Feminino , Doenças da Vesícula Biliar/cirurgia , Neoplasias da Vesícula Biliar/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Lesões Pré-Cancerosas , Estudos Prospectivos , Curva ROC
5.
Eur Radiol ; 29(7): 3467-3479, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30972545

RESUMO

OBJECTIVES: To compare dynamic contrast-enhanced MRI (DCE-MRI) data obtained using different prebolus T1 values in glioma grading and molecular profiling. METHODS: We retrospectively reviewed 83 cases of gliomas: 46 lower-grade gliomas (LGG; grades II and III) and 37 high-grade gliomas (HGG; grade IV). DCE-MRI maps of plasma volume fraction (Vp), extravascular-extracellular volume fraction (Ve), and tracer transfer constant from plasma to tissue (Ktrans) were obtained using a fixed T1 value of 1400 ms and a measured T1 obtained with variable flip angle (VFA). Tumour segmentations were performed and first-order histogram parameters were extracted from volumes of interest (VOIs) after co-registration with the perfusion maps. The two methods were compared using Wilcoxon matched-pairs signed-rank test and Bland-Altman analysis. Diagnostic accuracy was obtained and compared using ROC curve analysis and DeLong's test. RESULTS: Perfusion parameters obtained with the fixed T1 value were significantly higher than those obtained with the VFA. As regards diagnostic accuracy, there were no significant differences between the two methods both for glioma grading and molecular classification, except for few parameters of both methods. CONCLUSIONS: DCE-MRI data obtained with different prebolus T1 are not comparable and the definition of a prebolus T1 by T1 mapping is not mandatory since it does not improve the diagnostic accuracy of DCE-MRI. KEY POINTS: • DCE-MRI data obtained with different prebolus T1 are significantly different, thus not comparable. • The definition of a prebolus T1 by T1 mapping is not mandatory since it does not improve the diagnostic accuracy of DCE-MRI for glioma grading. • The use of a fixed T1 value represents a valid alternative to T1 mapping for DCE-MRI analysis.


Assuntos
Neoplasias Encefálicas/diagnóstico , Encéfalo/patologia , Meios de Contraste/farmacologia , Glioma/diagnóstico , Imagem por Ressonância Magnética/métodos , Gradação de Tumores , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Curva ROC , Estudos Retrospectivos , Adulto Jovem
6.
Eur Radiol ; 29(7): 3574-3583, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30993435

RESUMO

PURPOSE: We evaluated the detection rate and degree of motion artifact of the modified CAIPIRINHA-VIBE (mC-VIBE) without view-sharing and compare them with the CAIPIRINHA-Dixon-TWIST-VIBE (CDT-VIBE) with view-sharing on multi-arterial gadoxetic acid-enhanced liver MRI in the assessment of hepatocellular carcinoma (HCC). MATERIAL AND METHODS: We retrospectively identified 114 pathological-proven hepatic tumors in 114 patients with risk of HCC who underwent multi-arterial gadoxetic acid-enhanced MRI between June 2016 and June 2018. All patients underwent triple arterial phase imaging using the mC-VIBE without view-sharing (54 patients; 49 HCCs and 5 non-HCCs) or the CDT-VIBE with view-sharing (60 patients; 55 HCCs and 5 non-HCCs). We compared the detection rate of two sequences for HCC, with reference to LI-RADS.V.2017. We also compared the mean motion scores and proportions of transient severe motion (TSM) in two sequences. RESULT: For the examination using the mC-VIBE, the HCC-detection rate was significantly higher, compared with that using CDT-VIBE (93.9% [46/49] vs 80.0% [44/55], respectively; p = 0.047). For the examination with the mC-VIBE, mean motion scores were significantly lower compared with those of CDT-VIBE for all multi-arterial phases (1.21, 1.19, and 1.15 vs. 1.82, 1.85, and 1.84, respectively; p < 0.001 for all three comparisons). The proportion of TSM in the CDT-VIBE was significantly higher than that in the mC-VIBE (15.0% [9/60] vs 0.0% [0/54], respectively; p = 0.003). CONCLUSION: In multi-arterial phase gadoxetic acid-enhanced MRI, the mC-VIBE sequence without view-sharing has slightly higher HCC-detection rate and fewer motion artifacts compared with CDT-VIBE with view-sharing. KEY POINTS: • Multi-arterial phase using the mC-VIBE without view-sharing can overcome motion artifacts, resulting in providing optimal arterial phase imaging. • The HCC-detection rate is slightly higher with the mC-VIBE vs. CAIPIRINHA-Dixon-TWIST-VIBE with view-sharing (CDT-VIBE). • View-sharing of CDT-VIBE in the multi-arterial phase is associated with increased frequency of TSM.


Assuntos
Artefatos , Carcinoma Hepatocelular/diagnóstico , Gadolínio DTPA/farmacologia , Interpretação de Imagem Assistida por Computador/métodos , Neoplasias Hepáticas/diagnóstico , Fígado/patologia , Imagem por Ressonância Magnética/métodos , Meios de Contraste/farmacologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Estudos Retrospectivos
7.
Chin Med Sci J ; 34(1): 24-32, 2019 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-30961777

RESUMO

Objective To explore the ability of texture analysis of gadoxetic acid-enhanced magnetic resonance imaging (MRI) T1 mapping images, as well as T1-weighted (T1W), T2-weighted (T2W) and apparent diffusion coefficient (ADC) maps for distinguishing between varying degrees of hepatic fibrosis in an experimental rat model.Methods Liver fibrosis in rats was induced by carbon tetrachloride intraperitoneal injection for 4-12 weeks (n=30). In the control group (n=10) normal saline was applied. The MRI protocol contained T2W, diffusion weighted imaging, pre-and post-contrast image series of T1W and T1 mapping images. METAVIR score was used to grade liver fibrosis as normal (F0), mild fibrosis (F1-2), and advanced fibrosis (F3-4). Texture parameters including mean gray-level intensity (Mean), standard deviation (SD), Entropy, mean of positive pixels (MPP), Skewness, and Kurtosis were obtained. Nonparametric Mann-Whitney U test was used to compare the average value of each texture parameter in each sequence for assessing the difference between F0 and F≥1 as well as F0-2 and F3-4. Receiver operating characteristic (ROC) curves were obtained to assess the diagnosing accuracy of the parameters for differentiating no liver fibrosis from liver fibrosis and rats with liver fibrosis grading F0-2 from those with grading F3-4. The area under ROC curve (AUC) was calculated to evaluate the diagnostic efficiency of texture parameters.Results Finally, 20 rats completed MR T1 mapping image scan. The pathologic staging of these 20 rats was no fibrosis (F0, n=6), mild fibrosis (F1-2, n=5) and advanced fibrosis (F3-4, n=9). On pre-contrast T1 mapping image, Entropy was seen to be statistically significant higher in the F≥1 group than that in the F0 group at each spatial scaling factor (SSF) setting (P=0.015, 0.015, 0.015, 0.013, 0.015 and 0.018 respectively to SSF=0, 2, 3, 4, 5, 6), and Mean of the F≥1 rats was statistically significant higher than that of the F0 rats at SSF 4, 5, 6 (P=0.004, 0.006, and 0.013, respectively). Entropy and Mean showed a moderate diagnostic performance in most SSF settings of T1 mapping pre-contrast images for differentiation of normal liver from liver fibrosis.Conclusions Certain texture features of gadoxetic acid-enhanced MR images, especially the Entropy of non-contrast T1 mapping image, was found to be a useful biomarker for the diagnosis of liver fibrosis.


Assuntos
Meios de Contraste/farmacologia , Imagem de Difusão por Ressonância Magnética , Gadolínio DTPA/farmacologia , Cirrose Hepática/diagnóstico por imagem , Cirrose Hepática/fisiopatologia , Animais , Modelos Animais de Doenças , Masculino , Ratos , Ratos Sprague-Dawley
8.
Eur J Radiol ; 114: 1-5, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31005158

RESUMO

BACKGROUND: Vasodilator stress computed tomography perfusion (sCTP) imaging is complementary to coronary CT angiography (CCTA), used to determine the hemodynamic significance of coronary artery disease. However, it requires a separate image acquisition due to motion artifacts caused by higher heart rates during stress, resulting in increased iodine contrast dose and radiation. We sought to determine whether a novel motion correction algorithm applied to stress images would improve the visualization of the coronary arteries to potentially allow CCTA + sCTP evaluation in a single scan. METHODS: 28 patients referred for clinically indicated CCTA (iCT, Philips) underwent sCTP imaging (retrospective-gating with dose modulation; 100 kVp and 250 mA; 5.2 ± 4.3 mSv) after regadenoson (0.4 mg, Astellas). Stress images were reconstructed using standard filtered back-projection (FBP) and also processed to generate interaction-free coronary motion-compensated back-projection reconstructions (MCR). Each coronary artery from standard FBP and MCR images was viewed side-by-side by a reader blinded to the reconstruction technique, who graded severity of motion artifact by segment (scale 0-5, with 3 as the threshold for diagnostic quality) and to measure signal-to-noise and contrast-to-noise ratios (SNR, CNR). RESULTS: Visualization scores were higher with MCR for all coronary segments, including 14/86 (16%) segments deemed as non-diagnostic on FBP images. SNR (7 ± 2) and CNR (15 ± 8) were unchanged by motion-correction (7 ± 3, p = 0.88 and 15 ± 5, p = 0.94, respectively). CONCLUSIONS: MCR improves the visualization of coronary anatomy on sCTP images without degrading image characteristics. This algorithm is an important step towards the combined assessment of coronary anatomy and myocardial perfusion in a single scan, which will reduce study time, radiation exposure and contrast dose.


Assuntos
Doença da Artéria Coronariana/diagnóstico por imagem , Imagem de Perfusão do Miocárdio/métodos , Algoritmos , Artefatos , Angiografia por Tomografia Computadorizada/métodos , Meios de Contraste/farmacologia , Angiografia Coronária/métodos , Feminino , Frequência Cardíaca/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Movimento (Física) , Estudos Prospectivos , Doses de Radiação , Exposição à Radiação , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Tomografia Computadorizada por Raios X/métodos , Vasodilatadores/farmacologia
9.
J Mol Neurosci ; 68(2): 295-303, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30955191

RESUMO

Blood-brain barrier (BBB) dysfunction is involved in the pathogenesis of contrast-induced encephalopathy (CIE), which is a rare adverse event following angiography. In this study, we observed the dynamic effect and potential mechanism of ioversol on the BBB in rats. Eighty-one healthy rats were randomly divided into a normal control group (n = 9), ioversol group (n = 36), and 0.9% NaCl group (n = 36); the latter two groups were separately subdivided into four groups based on time points after treatment (0.5, 3, 6, and 24 h) (n = 9/group). Permeability of the BBB was measured by an Evans Blue (EB) assay. Levels of the tight junction (TJ) proteins ZO-1 and occludin were determined by western blot and immunofluorescence staining. EB content increased at 3 h after the administration of ioversol via the carotid artery and reached a peak at 6 h (P < 0.05), whereas it decreased to its normal level at 24 h. Western blot and immunofluorescence staining indicated that the expression of ZO-1 in brain tissues gradually decreased to its lowest level at 3 h, and then increased gradually, but was still lower than that of the normal control group at 24 h (P < 0.05). Occludin was similar, but its lowest expression appeared at 0.5 h. This study demonstrated that the permeability of BBB in rats increased first and then decreased after ioversol was injected into the carotid artery. The mechanism may be related to altered protein expression of TJs, which are important structures in BBB. Early intervention against TJ proteins may be an effective measure to prevent and treat CIE.


Assuntos
Barreira Hematoencefálica/metabolismo , Permeabilidade Capilar , Meios de Contraste/farmacologia , Ocludina/metabolismo , Ácidos Tri-Iodobenzoicos/farmacologia , Proteína da Zônula de Oclusão-1/metabolismo , Animais , Barreira Hematoencefálica/efeitos dos fármacos , Masculino , Ocludina/genética , Ratos , Ratos Sprague-Dawley , Proteína da Zônula de Oclusão-1/genética
10.
Eur Radiol ; 29(7): 3678-3685, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30888481

RESUMO

OBJECTIVE: To explore the image quality (IQ) and diagnostic value of 70 kVp turbo high-pitch coronary CT angiography (THP-CCTA) using automated tube voltage selection (ATVS) and 30 mL of low-concentration contrast agent. METHODS: Patients who underwent 70 kVp THP-CCTA using ATVS with 30 mL of contrast agent (group A) were prospectively enrolled, and those who underwent conventional CCTA (100/120 kVp, prospective sequential mode with 65-75 mL of contrast agent) (group B) were retrospectively selected for study. IQ was assessed subjectively on a 5-point scale, and diagnostic value was assessed based on invasive coronary angiography as the gold standard. Heart rate (HR), HR fluctuation (HRF), body mass index (BMI), effective radiation dose (ED), and iodine uptake (IU) were recorded. RESULTS: A total of 796 patients (398/398 in groups A/B) were included. Between-group differences in age, gender, BMI, HR, HRF, and IQ values were not significant. The ED/IU values were 0.3 ± 0.1 mSv/9.0 ± 0.0 g and 5.8 ± 1.8 mSv/22.9 ± 1.0 g in groups A and B, respectively (p < 0.01). The sensitivity, specificity, positive and negative predictive values, and accuracy of THP-CCTA for the diagnosis of ≥ 50% stenosis were 94.8%, 97.5%, 92.0%, 98.4%, and 96.9% respectively. The mean HR and coronary calcium score were independent predictors of diagnostic image quality, and the best cutoff values were 71.5 bpm and 444.1 respectively. CONCLUSION: This third-generation dual-source CT imaging modality, a 70-kVp THP-CCTA system using ATVS with 30 mL of low-concentration contrast agent, produces high-quality images with high diagnostic accuracy for significant stenosis, with ultra low ED and IU. This technique was most promising in individuals with an HR < 71.5 bpm and coronary calcium score < 444.1. KEY POINTS: • Turbo high-pitch CCTA using 70 kVp via automated tube voltage selection and 30 mL of low-concentration contrast agent is feasible. • This protocol provides high diagnostic accuracy for significant coronary stenosis and reduces radiation doses and iodine uptake significantly. • This protocol was most promising in individuals with an HR < 71.5 bpm and coronary calcium score < 444.1.


Assuntos
Angiografia por Tomografia Computadorizada/métodos , Meios de Contraste/farmacologia , Angiografia Coronária/métodos , Doença da Artéria Coronariana/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Reprodutibilidade dos Testes , Adulto Jovem
11.
Eur Radiol ; 29(7): 3584-3594, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30903328

RESUMO

OBJECTIVES: To compare look-locker inversion recovery (LLIR) and B1 inhomogeneity-corrected variable flip angle T1 mapping methods for estimation of liver function and prediction of hepatic insufficiency and decompensation on gadoxetic acid-enhanced MR imaging. METHODS: In this retrospective study, 248 patients with normal liver function, chronic liver disease, or cirrhosis underwent gadoxetic acid-enhanced liver MR imaging, including T1 mapping at 10-min and 20-min hepatobiliary phase (HBP) by using both methods. T1 relaxation times of the liver (T1Liver-pre, T1Liver-post) and the spleen (T1Spleen) were correlated between two methods. ΔT1Liver ([T1Liver-pre - T1Liver-post]/T1Liver-pre), adjusted T1Liver ([T1Spleen - T1Liver-post]/T1Spleen), and functional liver volume-to-weight ratio (liver volume on volumetric T1 map/[T1Liver-post × patient's weight]) were calculated. The diagnostic performance of T1 parameters and the predictive performance of models (serum marker, serum marker plus T1 parameter) were compared. RESULTS: T1Liver-post showed a strong correlation (r = 0.93, p < 0.001) between two methods but was significantly different. For depicting cirrhosis, LLIR-adjusted T1Liver at 10-min HBP showed the highest performance (p < 0.025). For predicting hepatic insufficiency and decompensation, LLIR-adjusted T1Liver (Akaike information criterion (AIC), 58.37; C-index, 0.867) and LLIR-T1Liver-post (AIC, 48.82; C-index, 0.885) at 10-min HBP showed the best performance, respectively, when added to serum albumin level. CONCLUSIONS: T1Liver-post showed a strong correlation between two methods but with significant differences. T1 mapping using LLIR at 10-min HBP with obtainment of adjusted T1Liver and T1Liver-post may be the best approach for estimation of liver function and prediction of hepatic insufficiency and decompensation. KEY POINTS: • T1 Liver-post showed a strong correlation between LLIR and B 1 inhomogeneity-corrected VFA methods, both at 10-min and 20-min HBP but with significant differences. • T1 Liver-post at 10-min and 20-min HBP using LLIR and B 1 inhomogeneity-corrected VFA methods could not be used interchangeably during the follow-up in patients with chronic liver disease (CLD) or cirrhosis. • T1 mapping using LLIR at 10-min HBP with obtainment of adjusted T1 Liver and T1 Liver-post may be the most suitable method and parameter for estimation of global liver function and prediction of clinical outcomes in patients with CLD or cirrhosis.


Assuntos
Gadolínio DTPA/farmacologia , Cirrose Hepática/diagnóstico , Testes de Função Hepática/métodos , Fígado/patologia , Imagem por Ressonância Magnética/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Meios de Contraste/farmacologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
12.
ACS Appl Mater Interfaces ; 11(14): 13069-13078, 2019 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-30883086

RESUMO

Multimodal probes are an asset for simplified, improved medical imaging. In particular, fluorescence and magnetic resonance imaging (MRI) are sought-after combined capabilities. Here, we show that pyrrolidin-2-one-capped manganese oxide nanoparticles (MnOpyrr NPs) combine MRI with fluorescence microscopy to function as efficient bifunctional bio-nanoprobes. We employ a one-pot synthesis for ca. 10 nm MnO NPs, wherein manganese(II) 2,4-pentadionate is thermally decomposed using pyrrolidin-2-one as a solvent and capping ligand. The MnOpyrr NPs are soluble in water without any further postsynthetic modifications. The r1 relaxivity and r2 /r1 ratio indicate that these NPs are potential T1 MRI contrast agents at clinical (3 T) and ultrahigh (9.4 T) magnetic fields. Serendipitously, the as-prepared NPs are photoluminescent. The unexpected luminescence is ascribed to the modification of the pyrrolidin-2-one during the thermal treatment. MnOpyrr NPs are successfully used to enable fluorescence microscopy of HeLa cells, demonstrating bifunctional imaging capabilities. A low cytotoxic response in two distinct cell types (HeLa, HepG2) supports the suitability of MnOpyrr NPs for biological imaging applications.


Assuntos
Meios de Contraste/farmacologia , Imagem por Ressonância Magnética/métodos , Nanopartículas/química , Imagem Óptica/métodos , Meios de Contraste/química , Fluorescência , Células HeLa , Humanos , Compostos de Manganês/química , Compostos de Manganês/farmacologia , Nanopartículas/administração & dosagem , Óxidos/química , Óxidos/farmacologia , Tamanho da Partícula
13.
Nano Lett ; 19(4): 2334-2342, 2019 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-30895796

RESUMO

Optical coherence tomography (OCT) can be utilized with significant speckle reduction techniques and highly scattering contrast agents for non-invasive, contrast-enhanced imaging of living tissues at the cellular scale. The advantages of reduced speckle noise and improved targeted contrast can be harnessed to track objects as small as 2 µm in vivo, which enables applications for cell tracking and quantification in living subjects. Here we demonstrate the use of large gold nanorods as contrast agents for detecting individual micron-sized polystyrene beads and single myeloma cells in blood circulation using speckle-modulating OCT. This report marks the first time that OCT has been used to detect individual cells within blood in vivo. This technical capability unlocks exciting opportunities for dynamic detection and quantification of tumor cells circulating in living subjects.


Assuntos
Meios de Contraste/farmacologia , Mieloma Múltiplo/sangue , Nanotubos/química , Células Neoplásicas Circulantes/patologia , Animais , Meios de Contraste/química , Ouro/química , Humanos , Camundongos , Mieloma Múltiplo/patologia , Poliestirenos/química , Análise de Célula Única/métodos , Tomografia de Coerência Óptica/métodos
14.
Toxicol Lett ; 308: 17-23, 2019 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-30902667

RESUMO

Three-dimensional T1-weighted MRI of mouse brain in vivo (9.4 T, 80 µm isotropic resolution) identified assemblies of nerve cell bodies in the habenula, hippocampal formation, locus coeruleus, dorsal motor nucleus of vagus, and nucleus ambiguus as high signal intensities, while suppressing the signals of white matter by magnetization transfer and of extracellular water protons by saturation. These observations indicate the presence of intracellular water protons with T1 values shortened by paramagnetic ions as the source of the bright signal. One day after an intraventricular injection of gadobutrol, a macrocyclic gadolinium-based contrast agent, T1-weighted MRI signal intensities of the nerve cell assemblies in the habenula, hippocampal formation, and locus coeruleus increased significantly. With simultaneous saturation of long-T1 protons of extracellular water, this finding indicates a T1-shortening of the intracellular water protons as a result of their interaction with gadolinium ions.


Assuntos
Encéfalo/diagnóstico por imagem , Meios de Contraste/administração & dosagem , Imagem de Difusão por Ressonância Magnética/métodos , Aumento da Imagem/métodos , Compostos Organometálicos/administração & dosagem , Animais , Encéfalo/patologia , Meios de Contraste/farmacologia , Feminino , Injeções Intraventriculares , Camundongos Endogâmicos C57BL , Neurônios/efeitos dos fármacos , Neurônios/patologia , Compostos Organometálicos/farmacologia , Prótons , Água/análise
15.
Cell Biochem Biophys ; 77(2): 157-163, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30924055

RESUMO

Iodinated radiographic contrast media is used in cancer radiography for cancer diagnosis. The aim of this present study was to examine five iodinated radiographic contrast media (IRCM) (i.e., iohexol, iopamidol, iobitridol, ioxaglate, and iodixanol) in terms of their cytotoxicity, mitochondria membrane potential (ΔΨm), and P-glycoprotein function in multidrug resistant K562/Dox cancer cells and corresponding sensitive cancer cells. The cytotoxicity was determined by colorimetric resazurin reduction assay. The ΔΨm and P-glycoprotein function was measured using a noninvasive functional spectrofluorometry. Rhodamine B, fluorescence probe, was used to estimate ΔΨm. The kinetic of P-glycoprotein-mediated efflux pirarubicin was used to monitor P-glycoprotein function in multidrug resistant (MDR) cancer cells. The results showed that ioxaglate and iodixanol show similar efficacy in MDR cancer cells and for their corresponding sensitive cancer cells. Iopamidol, iohexol, and iobitridol showed higher efficacy in MDR cancer cells than for the corresponding sensitive cancer cells by approximately 2 fold. The results also showed no significant change in the |ΔΨm| values in treated K562 and K562/Dox cancer cells when compared to the non-treated K562 and K562/Dox cancer cells. However, there were notable changes detected for iobitridol and iodixanol at 50 mgI/mL. Similarly, the results showed significant differences in P-glycoprotein function of K562/Dox cancer cells after treatment with IRCM when compared to the non-treated K562/Dox cancer cells, with iohexol and iodixanol being the notable exceptions once again. In this present study, IRCM exhibited cytotoxicity on MDR cancer cells and their corresponding sensitive cancer cells. IRCM also showed potential as an anticancer agent in the future.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Meios de Contraste/química , Resistencia a Medicamentos Antineoplásicos , Mitocôndrias/metabolismo , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/antagonistas & inibidores , Meios de Contraste/farmacologia , Doxorrubicina/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Humanos , Iodo/química , Iohexol/análogos & derivados , Iohexol/química , Iohexol/farmacologia , Células K562 , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Rodaminas/química , Ácidos Tri-Iodobenzoicos/química , Ácidos Tri-Iodobenzoicos/farmacologia
16.
Nano Lett ; 19(3): 2178-2185, 2019 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-30810045

RESUMO

Fluorescent nanodiamonds (fNDs) represent an emerging class of nanomaterials offering great opportunities for ultrahigh resolution imaging, sensing and drug delivery applications. Their biocompatibility, exceptional chemical and consistent photostability renders them particularly attractive for correlative light-electron microscopy studies providing unique insights into nanoparticle-cell interactions. Herein, we demonstrate a stringent procedure to image and quantify fNDs with a high contrast down to the single particle level in cells. Individual fNDs were directly visualized by energy-filtered transmission electron microscopy, that is, inside newly forming, early endosomal vesicles during their cellular uptake processes as well as inside cellular organelles such as a mitochondrion. Furthermore, we demonstrate the unequivocal identification, localization, and quantification of individual fNDs in larger fND clusters inside intracellular vesicles. Our studies are of great relevance to obtain quantitative information on nanoparticle trafficking and their various interactions with cells, membranes, and organelles, which will be crucial to design-improved sensors, imaging probes, and nanotherapeutics based on quantitative data.


Assuntos
Meios de Contraste/química , Nanodiamantes/química , Nanoestruturas/administração & dosagem , Rastreamento de Células/métodos , Meios de Contraste/farmacologia , Elétrons , Corantes Fluorescentes/administração & dosagem , Corantes Fluorescentes/química , Células HeLa , Humanos , Microscopia Eletrônica , Nanodiamantes/administração & dosagem , Nanodiamantes/ultraestrutura , Nanoestruturas/química , Organelas/efeitos dos fármacos
17.
ACS Appl Mater Interfaces ; 11(16): 14526-14537, 2019 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-30776888

RESUMO

Continuously updated diagnostic methods and advanced imaging methods have led to an increase in the early detection rate of small liver cancer; however, even with current diagnosis methods, it is still challenging to accurately judge a nodule with a diameter less than 2 cm whether it is hepatocellular carcinoma or liver cirrhosis. To solve this issue, a new technology is needed to distinguish above two kinds of liver nodules. There is an emerging imaging method that improves tissue resolution and sensitivity to detect micronodules with diameters less than 2 cm. To detect micronodules, photoacoustic imaging was used to provide noninvasive images at depths of several centimeters with a resolution of approximately 100 µm. To improve specificity, we developed a probe that specifically targets hepatocellular carcinoma by recognizing the biomarker GPC3 on the hepatocellular carcinoma cell membrane. The probe not only has a strong photoacoustic signal but also has a magnetic resonance signal. Furthermore, the material owns photothermal effect that absorbs longer wavelength light and releases heat that effectively and accurately kills tumor cells, thus improving patient's survival and postoperative quality of life. Herein, we present a new technology that uses photoacoustic imaging to image and target microhepatocellular carcinoma biological processes derived from liver cirrhosis with high spatial resolution.


Assuntos
Carcinoma Hepatocelular/diagnóstico por imagem , Meios de Contraste , Cirrose Hepática/diagnóstico por imagem , Neoplasias Hepáticas/diagnóstico por imagem , Imagem por Ressonância Magnética , Nanopartículas de Magnetita/química , Animais , Carcinoma Hepatocelular/metabolismo , Meios de Contraste/química , Meios de Contraste/farmacologia , Feminino , Células Hep G2 , Humanos , Cirrose Hepática/metabolismo , Neoplasias Hepáticas/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C
18.
Eur Radiol ; 29(7): 3595-3605, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30770969

RESUMO

OBJECTIVES: To develop and validate a radiomics nomogram for preoperative prediction of microvascular invasion (MVI) in patients with hepatocellular carcinoma (HCC). METHODS: The study included 157 patients with histologically confirmed HCC with or without MVI, and 110 patients were allocated to the training dataset and 47 to the validation dataset. Baseline clinical factor (CF) data were collected from our medical records, and radiomics features were extracted from the artery phase (AP), portal venous phase (PVP) and delay phase (DP) of preoperatively acquired CT in all patients. Radiomics analysis included tumour segmentation, feature extraction, model construction and model evaluation. A final nomogram for predicting MVI of HCC was established. Nomogram performance was assessed via both calibration and discrimination statistics. RESULTS: Five AP features, seven PVP features and nine DP features were effective for MVI prediction in HCC radiomics signatures. PVP radiomics signatures exhibited better performance than AP and DP radiomics signatures in the validation datasets, with the AUC 0.793. In the clinical model, age, maximum tumour diameter, alpha-fetoprotein and hepatitis B antigen were effective predictors. The final nomogram integrated the PVP radiomics signature and four CFs. Good calibration was achieved for the nomogram in both the training and validated datasets, with respective C-indexes of 0.827 and 0.820. Decision curve analysis suggested that the proposed nomogram was clinically useful, with a corresponding net benefit of 0.357. CONCLUSIONS: The above-described radiomics nomogram can preoperatively predict MVI in patients with HCC and may constitute a usefully clinical tool to guide subsequent personalised treatment. KEY POINTS: • No previously reported study has utilised radiomics nomograms to preoperatively predict the MVI of HCC using 3D contrast-enhanced CT imaging. • The combined radiomics clinical factor (CF) nomogram for predicting MVI achieved superior performance than either the radiomics signature or the CF nomogram alone. • Nomograms combing PVP radiomics and CF may be useful as an imaging marker for predicting MVI of HCC preoperatively and could guide personalised treatment.


Assuntos
Carcinoma Hepatocelular/diagnóstico , Hepatectomia , Neoplasias Hepáticas/diagnóstico , Nomogramas , Veia Porta/patologia , Tomografia Computadorizada por Raios X/métodos , Adulto , Carcinoma Hepatocelular/cirurgia , Meios de Contraste/farmacologia , Feminino , Humanos , Neoplasias Hepáticas/cirurgia , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Valor Preditivo dos Testes , Período Pré-Operatório , Estudos Retrospectivos
19.
Int Heart J ; 60(2): 477-481, 2019 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-30745532

RESUMO

This case report demonstrates a pair of monozygotic twins with hypertrophic cardiomyopathy (HCM) carrying the same pathogenic mutation of MYH7 (p.G768R; c.2302G>A), detected by whole exome and Sanger genetic sequencing methods. On multi-modality imaging, they were reported to have similar, but not identical, morphologic expression. Particularly, the clinical presentation and tissue characteristics were not the same. Late gadolinium enhancement (LGE) and T1 mapping of cardiac magnetic resonance showed different extents of myocardial fibrotic characteristics in the twins (twin A: 16.3% LGE and 32.6% extracellular volume [ECV] of the whole left ventricle; twin B: 5.4% LGE and 28.1% ECV of the whole left ventricle). This extraordinary case of HCM provides evidence on the complex pathophysiological mechanisms of HCM and suggests the likely impact of epigenetics and environmental factors on HCM phenotype.


Assuntos
Miosinas Cardíacas/genética , Cardiomiopatia Hipertrófica Familiar , Ecocardiografia/métodos , Eletrocardiografia/métodos , Ventrículos do Coração , Imagem Cinética por Ressonância Magnética/métodos , Cadeias Pesadas de Miosina/genética , Cardiomiopatia Hipertrófica Familiar/diagnóstico , Cardiomiopatia Hipertrófica Familiar/genética , Cardiomiopatia Hipertrófica Familiar/fisiopatologia , Meios de Contraste/farmacologia , Gerenciamento Clínico , Epigênese Genética , Feminino , Gadolínio/farmacologia , Interação Gene-Ambiente , Ventrículos do Coração/diagnóstico por imagem , Ventrículos do Coração/patologia , Humanos , Pessoa de Meia-Idade , Imagem Multimodal/métodos , Mutação , Tamanho do Órgão , Gêmeos Monozigóticos
20.
Chem Asian J ; 14(4): 509-526, 2019 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-30716209

RESUMO

Zinc is a biocompatible element that exists as the second most abundant transition metal ion and an indispensable trace element in the human body. Compared to traditional metal-organic complexes systems, d10 metal ZnII complexes not only exhibit a large Stokes shift and good photon stability but also possess strong emission and low cytotoxicity with a relatively small molecular weight. The use of ZnII complexes has emerged in the last decade as a versatile and convenient tool for numerous biological applications, including bioimaging, molecular and protein recognition, as well as photodynamic therapy. Herein, we review recent developments involving ZnII metal complexes applied as specific subcellular compartment imaging probes and their correlated utilizations.


Assuntos
Complexos de Coordenação/farmacologia , Corantes Fluorescentes/farmacologia , Zinco/química , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Meios de Contraste/química , Meios de Contraste/farmacologia , Complexos de Coordenação/química , Corantes Fluorescentes/química , Humanos , Membranas Intracelulares/metabolismo , Microscopia Confocal/métodos , Espectrometria de Fluorescência/métodos
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