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1.
NMR Biomed ; : e5174, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38712650

RESUMEN

The aim of the current study is to investigate the diagnostic value of R2* mapping versus reduced field-of-view diffusion-weighted imaging (rDWI) of the primary lesion of rectal cancer for preoperative prediction of nonenlarged lymph node metastasis (NLNM). Eighty-one patients with pathologically confirmed rectal cancer underwent preoperative R2* mapping and rDWI sequences before total mesorectal excisions and accompanying regional lymph node dissections. Two radiologists independently performed whole-tumor measurements of R2* and apparent diffusion coefficient (ADC) parameters on primary lesions of rectal cancer. Patients were divided into positive (NLNM+) and negative (NLNM-) groups based on their pathological analysis. The tumor location, maximum diameter of the tumor, and maximum short diameter of the lymph node were assessed. R2* and ADC, pT stage, tumor grade, status of mesorectal fascia, and extramural vascular invasion were also studied for their potential relationships with NLNM using multivariate logistic regression analysis. The NLNM+ group had significantly higher R2* (43.56 ± 8.43 vs. 33.87 ± 9.57, p < 0.001) and lower ADC (1.00 ± 0.13 vs. 1.06 ± 0.22, p = 0.036) than the NLNM- group. R2* and ADC were correlated to lymph node metastasis (r = 0.510, p < 0.001 for R2*; r = -0.235, p = 0.035 for ADC). R2* and ADC showed good and moderate diagnostic abilities in the assessment of NLNM status with corresponding area-under-the-curve values of 0.795 and 0.636. R2* provided a significantly better diagnostic performance compared with ADC for the prediction of NLNM status (z = 1.962, p = 0.0498). The multivariate logistic regression analysis demonstrated that R2* was a compelling factor of lymph node metastasis (odds ratio = 56.485, 95% confidence interval: 5.759-554.013; p = 0.001). R2* mapping had significantly higher diagnostic performance than rDWI from the primary tumor of rectal cancer in the prediction of NLNM status.

2.
Eur Radiol ; 34(7): 4686-4696, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38133674

RESUMEN

OBJECTIVES: To investigate the feasibility of non-contrast-enhanced MR angiography (NCE-MRA) in evaluating the morphology and blood supply of left gastric vein (LGV) in patients with gastroesophageal varices. METHODS: Between March 2021 and October 2022, patients with gastroesophageal varices and who underwent NCE-MRA were retrospectively reviewed. In order to evaluate the blood supply of LGV, superior mesenteric vein (SMV) and splenic vein (SV) were visualized separately by using inflow-sensitive inversion recovery sequence. Two radiologists independently assessed the image quality, determined the origination and the blood supply of LGV, and measured the diameter of LGV. The origination and diameter of LGV were compared between NCE-MRA and contrast-enhanced CT. Differences in blood supply were compared between LGVs with different originations. RESULTS: A total of 53 patients were enrolled in this study and the image quality was categorized as good or excellent in 52 patients. No significant differences were observed in visualizing the origination and the diameter of LGV between NCE-MRA and contrast-enhanced CT (p > .05). The blood supply of LGV was related to its origination (p < .001). Most LGVs with SV origination were supplied by SV. If LGV was originated from the portal vein (PV), about 70% of them were supplied by both SV and SMV. Compared with LGVs with SV origination, LGVs with PV origination showed more chance to receive blood from SMV (p < .001). CONCLUSION: Non-contrast-enhanced MR angiography appears to be a reliable technique in evaluating the morphology and blood supply of LGV in patients with gastroesophageal varices. CLINICAL RELEVANCE STATEMENT: Non-contrast-enhanced MR angiography provides valuable information for the management of gastroesophageal varices. Especially, it benefits patients with renal insufficiency. KEY POINTS: • Non-contrast-enhanced MR angiography using inflow-sensitive inversion recovery technique can be used for evaluating not only morphology as CT but also blood supply of left gastric vein. • The blood supply of left gastric vein is related to its origination and left gastric vein with portal vein origination shows more chance to receive blood from superior mesenteric vein.


Asunto(s)
Várices Esofágicas y Gástricas , Estudios de Factibilidad , Angiografía por Resonancia Magnética , Humanos , Masculino , Femenino , Persona de Mediana Edad , Várices Esofágicas y Gástricas/diagnóstico por imagen , Estudios Retrospectivos , Angiografía por Resonancia Magnética/métodos , Anciano , Adulto , Estómago/irrigación sanguínea , Estómago/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Vena Esplénica/diagnóstico por imagen , Venas Mesentéricas/diagnóstico por imagen , Medios de Contraste
3.
Eur Radiol ; 33(3): 1862-1872, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36255487

RESUMEN

OBJECTIVES: To investigate whether volumetric visceral adipose tissue (VAT) features extracted using radiomics and three-dimensional convolutional neural network (3D-CNN) approach are effective in differentiating Crohn's disease (CD) and ulcerative colitis (UC). METHODS: This retrospective study enrolled 316 patients (mean age, 36.25 ± 13.58 [standard deviation]; 219 men) with confirmed diagnosis of CD and UC who underwent CT enterography between 2012 and 2021. Volumetric VAT was semi-automatically segmented on the arterial phase images. Radiomics analysis was performed using principal component analysis (PCA) and the least absolute shrinkage and selection operator (LASSO) logistic regression algorithm. We developed a 3D-CNN model using VAT imaging data from the training cohort. Clinical covariates including age, sex, modified body mass index, and disease duration that impact VAT were added to the machine learning model for adjustment. The model's performance was evaluated on the testing cohort separating from the model's development process by its discrimination and clinical utility. RESULTS: Volumetric VAT radiomics analysis with LASSO had the highest AUC value of 0.717 (95% CI, 0.614-0.820), though difference of diagnostic performance among the 3D-CNN model (AUC = 0.693; 95% CI, 0.587-0.798) and radiomics analysis with PCA (AUC = 0.662; 95% CI, 0.548-0.776) and LASSO have not reached statistical significance (all p > 0.05). The radiomics score was higher in UC than in CD on the testing cohort (mean ± SD, UC 0.29 ± 1.05 versus CD -0.60 ± 1.25; p < 0.001). The LASSO model with adjustment of clinical covariates reached an AUC of 0.775 (95%CI, 0.683-0.868). CONCLUSION: The developed volumetric VAT-based radiomics and 3D-CNN models provided comparable and effective performance for the characterization of CD from UC. KEY POINTS: • High-output feature data extracted from volumetric visceral adipose tissue on CT enterography had an effective diagnostic performance for differentiating Crohn's disease from ulcerative colitis. • With adjustment of clinical covariates that cause difference in volumetric visceral adipose tissue, adjusted clinical machine learning model reached stronger performance when distinguishing Crohn's disease patients from ulcerative colitis patients.


Asunto(s)
Colitis Ulcerosa , Enfermedad de Crohn , Enfermedades Inflamatorias del Intestino , Humanos , Enfermedad de Crohn/diagnóstico por imagen , Colitis Ulcerosa/diagnóstico por imagen , Grasa Intraabdominal/diagnóstico por imagen , Estudios Retrospectivos , Diagnóstico Diferencial , Enfermedades Inflamatorias del Intestino/diagnóstico , Tomografía Computarizada por Rayos X , Fenotipo , Aprendizaje Automático
4.
J Magn Reson Imaging ; 56(3): 739-751, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35049076

RESUMEN

BACKGROUND: The clinical outcomes of patients with intrahepatic cholangiocarcinoma (ICC) after partial hepatectomy remain suboptimal. Identifying patients with poor outcomes before surgery is urgently required. PURPOSE: To develop a multiparametric magnetic resonance imaging (MRI)-based radiomic signature to evaluate overall survival (OS) preoperatively and to investigate its incremental value for disease stratification. STUDY TYPE: Retrospective. SUBJECTS: One hundred and sixty-three patients with pathologically defined ICC, divided into training (N = 115) and validation sets (N = 48). SEQUENCE: Three-dimensional T1-weighted gradient-echo sequence with and without contrast agent, T2-weighted fast spin-echo sequence, and diffusion-weighted imaging with single-shot echo-planar sequence at 1.5 T or 3.0 T. ASSESSMENT: OS was defined as the time from the date of surgery to death or last contact. The radiomic signature was built based on the least absolute shrinkage and selection operator regression model. A clinicopathologic-radiographic (CPR) model and a combined model integrating radiomic signature with CPR factors were developed with multivariable Cox regression models. STATISTICAL TESTS: Harrell's concordance index (C-index) was used to compare the discrimination of different models. Net reclassification index (NRI) and integrated discrimination improvement (IDI) were used to quantify the improvement of prognostic accuracy after adding radiomic signature. RESULTS: The high-risk patients of death defined by the radiomic signature showed significantly lower OS compared with low-risk patients in validation set (3-year OS 17.1% vs. 56.4%, P < 0.001). Integrating radiomic signature into tumor, node, and metastasis (TNM) staging system significantly improved the prognostic accuracy compared with TNM stage alone (validation set C-index 0.745 vs. 0.649, P = 0.039, NRI improvement 39.9%-43.8%, IDI improvement 16.1%-19.4%). The radiomic signature showed no significant difference of C-index with postoperative CPR model (validation set, 0.698 vs. 0.674, P = 0.752). Incorporating the radiomic signature into CPR model significantly improved prognostic accuracy (NRI improvement 32.5%-34.3%, IDI improvement 8.1%-12.9%). DATA CONCLUSION: Multiparametric MRI-based radiomic signature is a potential biomarker for preoperative prognostic evaluation of ICC patients. LEVEL OF EVIDENCE: 4 TECHNICAL EFFICACY: Stage 4.


Asunto(s)
Neoplasias de los Conductos Biliares , Colangiocarcinoma , Imágenes de Resonancia Magnética Multiparamétrica , Neoplasias de los Conductos Biliares/diagnóstico por imagen , Neoplasias de los Conductos Biliares/cirugía , Conductos Biliares Intrahepáticos , Colangiocarcinoma/diagnóstico por imagen , Colangiocarcinoma/cirugía , Hepatectomía , Humanos , Imagen por Resonancia Magnética/métodos , Estudios Retrospectivos
5.
Nitric Oxide ; 118: 31-38, 2022 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-34756996

RESUMEN

Hydrogen Sulfide (H2S) mediates biological effects in a variety of ways. Due to its strong reducing potential, H2S has been recognized to have an important role in oxidative stress induced hypoxia. It has been reported that H2S production and miRNA can mutually regulate each other. H2S is produced by the catalytic activity of cystathionine-ß-synthase (CBS), which is under the regulation of miRNAs. In this study, we used target gene prediction software, and identified miR-203 as a potential regulator of CBS. We verified this finding using an oxygen and glucose deprivation (OGD) hypoxia cell model in SH-SY5Y cells and pMIR-REPORT™ luciferase miRNA expression reporter vector. Furthermore, transfecting SH-SY5Y cells with miRNA agomir (agonist) and antagomir (antagonist) by lipofectamin RNAiMAX, we further validated miR-203 as a direct regulator of CBS. We also found that miR-203 protects from cell injury by regulating lipid peroxidation, cell apoptosis, and mitochondrial membrane potential. These findings suggest that while over-expression of miR-203 can aggravate OGD induced cell injury, inhibition of miR-203 can protect against OGD induced cell injury. Based on our data and that of others, we propose that miR-203 may regulate oxidative stress induced cell injury by regulating CBS expression and adjusting the levels of H2S production.


Asunto(s)
Cistationina betasintasa/metabolismo , Sulfuro de Hidrógeno/metabolismo , MicroARNs/metabolismo , Estrés Oxidativo/fisiología , Animales , Antagomirs/farmacología , Apoptosis/efectos de los fármacos , Apoptosis/fisiología , Línea Celular Tumoral , Humanos , Infarto de la Arteria Cerebral Media/metabolismo , Peroxidación de Lípido/fisiología , Masculino , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Potencial de la Membrana Mitocondrial/fisiología , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Ratas Sprague-Dawley
6.
J Nanobiotechnology ; 20(1): 226, 2022 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-35549947

RESUMEN

BACKGROUND: Conventional chemotherapy has poor efficacy in triple-negative breast cancer (TNBC) which is highly heterogeneous and aggressive. Imaging-guided therapy is usually combined with diverse treatment modalities, could realize the integration of diagnosis and treatments. Therefore, the primary challenge for combinational therapy is designing proper delivery systems to accomplish multiple synergistic effects. RESULTS: Herein, a facile nanoplatform was manufactured to fulfill the all-in-one approaches for TNBC combinational therapy. Fe3+-based metal-phenolic networks (MPNs) with bovine serum albumin (BSA) modification served as drug delivery carriers to encapsulate bleomycin (BLM), forming BFE@BSA NPs. The self-assembly mechanism, pH-responsive drug release behavior, and other physicochemical properties of this system were characterized. The potential of BFE@BSA NPs as photothermal transduction agents and magnetic resonance imaging (MRI) contrast agents was explored. The synergistic anti-tumor effects consisting of BLM-induced chemotherapy, Fenton reactions-mediated chemodynamic therapy, and photothermal therapy-induced apoptosis were studied both in vitro and in vivo. Once internalized into tumor cells, released BLM could cause DNA damage, while Fenton reactions were initiated to produce highly toxic •OH. Upon laser irradiation, BFE@BSA NPs could convert light into heat to achieve synergistic effects. After intravenous administration, BFE@BSA NPs exhibited great therapeutic effects in 4T1 tumor xenograft model. Moreover, as T1-weighted MRI contrast agents, BFE@BSA NPs could provide diagnosis and treatment monitoring for individualized precise therapy. CONCLUSIONS: A nano-system that integrated imaging and combinational therapy (chemotherapy, chemodynamic therapy and photothermal therapy) were developed to kill the tumor and monitor therapeutic efficacy. This strategy provided an all-in-one theranostic nanoplatform for MRI-guided combinational therapy against TNBC.


Asunto(s)
Nanopartículas , Neoplasias , Neoplasias de la Mama Triple Negativas , Línea Celular Tumoral , Medios de Contraste , Portadores de Fármacos/uso terapéutico , Humanos , Imagen por Resonancia Magnética , Nanopartículas/química , Neoplasias/tratamiento farmacológico , Fototerapia/métodos , Terapia Fototérmica , Albúmina Sérica Bovina/uso terapéutico , Neoplasias de la Mama Triple Negativas/diagnóstico por imagen , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico
7.
Biochem Genet ; 60(6): 2268-2285, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35325440

RESUMEN

To further understand the molecular mechanism for rice male reproduction, a rice male sterile mutant paa1 was screened from the rice mutant library generated by treatment with 60Coγ-rays. Genetic analysis revealed that paa1 is controlled by a single- recessive nuclear gene, and the anthers of the paa1 mutant were smaller than those of WT plants with a white color. Histological analysis demonstrated that the anthers of the paa1 mutant began to turn abnormal at the microspore stage after meiosis, with abnormal degradation of tapetum, deformed Ubisch bodies, and defective pollen exine. TUNEL assay results also confirmed the delay of tapetum PCD in paa1. Map-based cloning was performed for the PAA1 location. As a result, PAA1 was located in a 88-kb region at the end of chromosome 10, which comprises a total of seven candidate genes, and no genes related to anther development have been reported in this region. The results indicate that PAA1 is an essential gene in regulating tapetum development and pollen/microspore formation after rice meiosis.


Asunto(s)
Regulación de la Expresión Génica de las Plantas , Oryza , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Polen/genética , Polen/metabolismo , Meiosis/genética , Flores/genética
8.
J Nanobiotechnology ; 19(1): 415, 2021 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-34895243

RESUMEN

BACKGROUND: Immunochemotherapy is a potent anti-tumor strategy, however, how to select therapeutic drugs to enhance the combined therapeutic effect still needs to be explored. METHODS AND RESULTS: Herein, a magnetic resonance nanoprobe (MnP@Lip) with STING (Stimulator of INterferon Genes) activation character was synthesized and co-administered with platinum-based chemotherapeutics for enhanced immunochemotherapy. MnP@Lip nanoparticles was prepared by simple fabrication process with good reproducibility, pH-sensitive drug release behavior and biocompatibility. In vitro experiments elucidated that Mn2+ can promote the polarization of M0 and/or M2 macrophages to M1 phenotype, and promote the maturation of BMDC cells. Upon Mn2+ treatment, the STING pathway was activated in tumor cells, mouse lung epithelial cells, and immune cells. More importantly, anti-tumor experiments in vivo proved that MnP@Lip combined with platinum-based chemotherapeutics increased T cells infiltration in the tumor microenvironment, and inhibited tumor growth in the orthotopic therapeutic and postoperative tumor models. CONCLUSIONS: This kind of therapeutic strategy that combined MnP@Lip nanoparticles with platinum-based chemotherapeutics may provide a novel insight for immunochemotherapy.


Asunto(s)
Antineoplásicos , Sondas Moleculares , Nanopartículas , Platino (Metal) , Animales , Antineoplásicos/química , Antineoplásicos/farmacocinética , Antineoplásicos/farmacología , Línea Celular Tumoral , Células Cultivadas , Femenino , Inmunoterapia , Macrófagos/efectos de los fármacos , Imagen por Resonancia Magnética , Proteínas de la Membrana/metabolismo , Ratones , Ratones Endogámicos C57BL , Sondas Moleculares/química , Sondas Moleculares/farmacocinética , Nanopartículas/química , Nanopartículas/metabolismo , Neoplasias Experimentales , Platino (Metal)/química , Platino (Metal)/farmacocinética , Platino (Metal)/farmacología , Microambiente Tumoral/efectos de los fármacos
9.
NMR Biomed ; 33(6): e4293, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32175654

RESUMEN

Enteric contrast agents are important in gastrointestinal MRI. However, no currently available agent is well established as the standard of care. In this study, in vitro relaxivities of manganese threonine chelate (Mn-Thr), a common nutritional food supplement, were measured at 1.5 T and 3 T with further investigation of its efficacy and safety in vivo as an enteric contrast agent. According to the calculated relaxivities, T1 W and T2 W TSE sequences of Mn-Thr solutions at different concentrations were acquired, and the optimal concentration for dark lumen imaging on both T1 W and T2 W images was determined in vitro. To validate the optimal concentration in vivo, eight Sprague-Dawley rats were randomly divided into two groups. Each group received rectal injection of either 2.00 g/L (about 3.80 mM) Mn-Thr or saline as an enteric contrast agent and underwent MRI. After a time interval of one week, the same procedures were repeated with the alternative contrast agent. Animals were sacrificed after the second MRI. Tissue manganese quantification and histopathological examination were obtained. Qualitative MR image quality assessments were performed and compared between Mn-Thr and saline. Measured T1 and T2 relaxivities of Mn-Thr were significantly higher than those of MnCl2 in vitro (p < 0.05). At the concentration of 2.00 g/L (about 3.80 mM), Mn-Thr produced a dark lumen on T1 W and T2 W images both in vitro and in vivo. Compared with saline, Mn-Thr showed significantly more homogenous luminal signal and increased bowel wall conspicuity in image quality assessments. Tissue manganese concentrations were not significantly different between two groups. Histopathological examinations were normal in both groups. Our data suggest that Mn-Thr possesses favorable paramagnetic properties and can create a homogenous dark lumen on T1 W and T2 W images without obvious side effects in healthy rats. As a commercially available nutritional food supplement, Mn-Thr appears to be a promising enteric contrast agent for MRI.


Asunto(s)
Quelantes/química , Imagen por Resonancia Magnética , Manganeso/química , Treonina/química , Animales , Especificidad de Órganos , Fantasmas de Imagen , Proyectos Piloto , Ratas Sprague-Dawley
10.
AJR Am J Roentgenol ; 214(2): 383-389, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31670586

RESUMEN

OBJECTIVE. The objective of our study was to compare the feasibility of R2* and apparent diffusion coefficient (ADC) for differentiating tumor grade and T category of bladder cancer. SUBJECTS AND METHODS. In this prospective study, 58 patients with pathologically confirmed bladder cancers underwent pretreatment T2*-weighted imaging and DWI on a 3-T MRI unit. The apparent transverse relaxation rate R2*, which is derived from T2*-weighted imaging, and ADC, which is derived from DWI, were calculated and compared between low- and high-grade bladder cancers as well as between non-muscle-invasive bladder cancers (NMIBCs) and muscle-invasive bladder cancers (MIBCs) using the Mann-Whitney U test. The diagnostic performances of R2*, ADC, and the combination of R2* and ADC were evaluated through an ROC analysis. RESULTS. Significant differences were found in R2* (mean ± SD, 16.55 ± 5.54 vs 20.96 ± 7.75 s-1; p = 0.001) and ADC (1.62 ± 0.31 vs 1.33 ± 0.21 × 10-3 mm2/s; p < 0.001) between lowand high-grade bladder cancers. R2* was significantly higher (22.56 ± 8.41 vs 18.06 ± 6.46 s-1; p = 0.008) and ADC was considerably lower (1.21 ± 0.18 vs 1.53 ± 0.27 × 10-3 mm2/s; p < 0.001) in MIBCs than in NMIBCs. The AUCs for differentiating low-from high-grade groups were 0.714 using R2* and 0.779 using ADC. AUCs for distinguishing between NMIBC and MIBC groups using R2* and ADC were 0.682 and 0.850, respectively. CONCLUSION. In addition to ADC, R2* can be used as a quantitative imaging biomarker to provide additional information for tumor characterization of bladder cancer.


Asunto(s)
Imagen de Difusión por Resonancia Magnética/métodos , Neoplasias de la Vejiga Urinaria/diagnóstico por imagen , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Clasificación del Tumor , Estadificación de Neoplasias , Estudios Prospectivos , Neoplasias de la Vejiga Urinaria/patología , Neoplasias de la Vejiga Urinaria/cirugía
11.
J Magn Reson Imaging ; 49(4): 975-983, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30277628

RESUMEN

BACKGROUND: Accurate differentiation between intrahepatic mass-forming cholangiocarcinoma (IMCC) and hepatocellular carcinoma (HCC) is needed because treatment and prognosis differ significantly. PURPOSE: To explore whether volumetric apparent diffusion coefficient (ADC) histogram analysis can provide additional value to dynamic enhanced MRI in differentiating IMCC from HCC. STUDY TYPE: Retrospective. POPULATION: In all, 131 patients with pathologically proven IMCC (n = 33) or HCC (n = 98). FIELD STRENGTH/SEQUENCE: 3.0T MRI/conventional T1 -weighted imaging (T1 WI), T2 WI, and diffusion-weighted imaging (DWI) with b value of 800 sec/mm2 , dynamic enhanced MRI with gadobenate dimeglumine. ASSESSMENT: Dynamic enhanced MR images were analyzed by two independent reviewers using a five-point scale to determine the diagnosis. Volumetric ADC assessments were performed independently by two radiologists to obtain different histogram parameters for each lesion. Quantitative histogram parameters were compared between the IMCC group and HCC group. Diagnostic performance of dynamic enhanced MRI, volumetric ADC histogram analysis, and the combination of both were analyzed. STATISTICAL TESTS: Intraclass correlation coefficient (ICC) analysis, independent Student's t-test, or Mann-Whitney U-test, receiver operator characteristic (ROC) curves analysis, and McNemar test. RESULTS: The sensitivity and specificity for dynamic enhanced MRI to differentiate IMCC from HCC were 82.1% and 82.6%, respectively. For all volumetric ADC histogram parameters, the 75th percentile ADC (ADC75% ) had the highest AUC (0.791) in differentiating IMCC from HCC, with sensitivity and specificity of 69.7% and 77.6%, respectively. When combining dynamic enhanced MRI with ADC75% , the sensitivity and specificity were 82.1% and 91.9%, respectively. Compared to dynamic enhanced MRI alone, the specificity for combined dynamic enhanced MRI and ADC75% was significantly increased (P = 0.008). DATA CONCLUSION: Volumetric ADC histogram analysis provides additional value to dynamic enhanced MRI in differentiating IMCC from HCC. LEVEL OF EVIDENCE: 3 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2019;49:975-983.


Asunto(s)
Carcinoma Hepatocelular/diagnóstico por imagen , Colangiocarcinoma/diagnóstico por imagen , Neoplasias Hepáticas/diagnóstico por imagen , Anciano , Imagen de Difusión por Resonancia Magnética , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Masculino , Meglumina/análogos & derivados , Meglumina/farmacología , Persona de Mediana Edad , Compuestos Organometálicos/farmacología , Pronóstico , Reproducibilidad de los Resultados , Estudios Retrospectivos , Sensibilidad y Especificidad , Programas Informáticos
12.
Acta Radiol ; 60(6): 694-701, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30205704

RESUMEN

BACKGROUND: The availability of data in the medical literature for the T2 relaxivities of the Gd-based contrast agents (GBCAs) is limited. A comprehensive comparison between the agents available commercially (other than in Europe) is lacking, with no data available that most closely reflect the clinic, which is in human whole blood at body temperature. PURPOSE: To complement the existing literature by determining T2 relaxivity data for eight GBCAs in vitro. MATERIAL AND METHODS: The relaxivities of eight GBCAs diluted in human whole blood at 1.5 and 3 T were determined at 37 ± 0.5 °C. Gd was in the range of 0-4 mM. Multi-echo sequences with variable echo times were acquired using a phantom containing a dilution series with each agent, and SigmaPlot 12.0 was used to calculate the R2 relaxation rate and finally r2. Statistical comparisons between agents and field strengths were conducted. RESULTS: The relationship between R2 vs. Gd was observed to be linear at 1.5 and 3 T, with a mild increase in r2 from 1.5 to 3 T for all GBCAs. T2 relaxivity data were compared with prior results. The GBCAs are closely clustered into two groups, with higher r2 noted for the two lipophilic (those with partial hepatobiliary excretion) compounds. CONCLUSION: The r2 values at 1.5 and 3 T, determined for the eight GBCAs still clinically available (other than in Europe), provide a definitive baseline for future evaluations, including theoretical calculations of signal intensity and their clinical impact on T2-weighted scans.


Asunto(s)
Sangre/metabolismo , Medios de Contraste/farmacocinética , Gadolinio/farmacocinética , Imagen por Resonancia Magnética/métodos , Humanos , Técnicas In Vitro
13.
J Magn Reson Imaging ; 47(4): 967-975, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-28691219

RESUMEN

PURPOSE: To compare image quality (IQ) of reduced field-of-view (rFOV) and full FOV (fFOV) diffusion-weighted imaging (DWI) sequences at 3T, with histological T staging of rectal cancer as a reference standard. MATERIALS AND METHODS: In all, 81 patients with rectal cancer received magnetic resonance (MR) scans (3.0T), including both rFOV and fFOV DWI sequences. The signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were quantitatively evaluated using the paired t-test. Two radiologists independently assessed subjective IQ parameters, including image sharpness, distortion, artifacts, lesion conspicuity, and overall subjective IQ of both sequences. The Wilcoxon signed rank test was used to compare subjective IQ scores and tumor apparent diffusion coefficients (ADCs) between DWI sequences. Spearman correlation analysis was used to correlate ADC values and corresponding T staging of rectal cancer. RESULTS: CNR was significantly higher in rFOV DWI than in fFOV DWI (7.15 ± 2.77 vs. 5.39 ± 2.08, P < 0.001). SNR was significantly higher in rFOV DWI than in fFOV DWI (44.17 ± 11.01 vs. 34.76 ± 13.30, P < 0.001). The subjective IQ parameters of rFOV DWI sequence were rated superior to those of fFOV DWI sequence by both readers (P < 0.001). No significant differences between mean tumor ADC values of both sequences (0.991 ± 0.121 vs. 0.100 ± 0.126 × 10-3 mm2 /s, P = 0.617) were noted. Apart from T1 stage, T staging of rectal cancer was inversely correlated with ADC values of rFOV DWI (r = -0.688, P < 0.001) and fFOV DWI sequences (r = -0.641, P < 0.001). CONCLUSION: The rFOV DWI sequence provided significantly better IQ and lesion conspicuity than the fFOV DWI sequence. In addition, rFOV and fFOV DWI sequences can be used in evaluation of histological T staging of rectal cancer. LEVEL OF EVIDENCE: 3 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2018;47:967-975.


Asunto(s)
Imagen de Difusión por Resonancia Magnética/métodos , Interpretación de Imagen Asistida por Computador/métodos , Neoplasias del Recto/diagnóstico por imagen , Neoplasias del Recto/patología , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Recto/diagnóstico por imagen , Recto/patología , Reproducibilidad de los Resultados , Estudios Retrospectivos , Sensibilidad y Especificidad , Adulto Joven
14.
Nitric Oxide ; 78: 11-21, 2018 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-29777774

RESUMEN

AIMS: Ischemic stroke is one of the leading causes of death worldwide. MicroRNAs (miRNAs) have been reported to be implicated in cerebral hypoxia injury and could serve as a therapeutic target. As the third gasotransmitter, hydrogen sulfide (H2S) plays a critical role in hypoxia-induced injury in the central nervous system. Cystathionine ß-synthase (CBS) is the main enzyme catalyzing the production of H2S in brain. The objective of this study was to investigate the effect of miR-125b-5p on protecting against oxygen and glucose deprivation (OGD) injury in PC-12 cells by regulating CBS and H2S generation. RESULTS: The level of miR-125b-5p was increased in the rat MCAO model as well as OGD model in PC-12 cells. Meanwhile, CBS expression was remarkably downregulated. Overexpression of miR-125b-5p reduced CBS expression, decreased the H2S generation, and deteriorated OGD injury in PC-12 cells. On the contrary, silencing miR-125b-5p protected PC-12 cells from OGD injury by upregulated CBS and H2S levels. We found the protective effect of miR-125b-5p inhibition was associated with anti-oxidative and anti-apoptotic cell signaling through decreasing ROS level and reducing mitochondrial membrane potential (ΔΨm). Furthermore, the protective effect was absent when CBS was knockdown in PC-12 cells. INNOVATION AND CONCLUSION: Our research discovered the regulation of CBS by miR-125b-5p. Besides, we provide the evidence for the therapeutic potential of miR-125b-5p inhibition for cerebral ischemia via CBS/H2S pathway.


Asunto(s)
Cistationina betasintasa/metabolismo , Sulfuro de Hidrógeno/metabolismo , Infarto de la Arteria Cerebral Media/fisiopatología , MicroARNs/metabolismo , Animales , Apoptosis/fisiología , Hipoxia de la Célula/fisiología , Técnicas de Silenciamiento del Gen , Masculino , Potencial de la Membrana Mitocondrial/fisiología , MicroARNs/antagonistas & inhibidores , MicroARNs/genética , MicroARNs/farmacología , Estrés Oxidativo/fisiología , Células PC12 , Sustancias Protectoras/farmacología , Ratas , Ratas Sprague-Dawley , Especies Reactivas de Oxígeno/metabolismo , Regulación hacia Arriba
15.
Int J Clin Pract ; 70 Suppl 9B: B5-B15, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27577514

RESUMEN

BACKGROUND: Imaging communities have already reached a consensus that the radiation dose of computed tomography (CT) should be reduced as much as reasonably achievable to lower population risks. Increasing attention is being paid to iodinated contrast media (CM) induced nephrotoxicity (CIN); a decrease in the intake of iodinated CM is required by increasingly more radiologists. Theoretically, the radiation dose varies with the tube current time and square of the tube voltage, with higher iodine contrast at low photon energies (Huda et al. [2000] Radiology, 21 7, 430-435).The use of low tube voltage is a promising strategy to reduce both the radiation dose and CM burden. The term 'double low' has been coined to describe scanning protocols that reduce radiation dose and iodine intake synchronously. These protocols are becoming increasingly popular in the clinical setting. PURPOSE: The aim of this review was to describe all original studies using the 'double low' strategy in the last 5 years. METHODS: We searched an online electronic database (PubMed) from January 2011 to December 2015 for original studies published on the relationship of low tube voltage with low radiation dose and low iodine contrast media burden in patients undergoing CT scans. Studies that failed to reduce radiation dose or iodine CM burden were excluded in this study. RESULTS: Thirty-seven studies aimed at reducing radiation dose using low tube voltage combined with iodine CM reduced protocols were included in this study. Most studies evaluated conditions associated with arteries. Four were cerebral and neck computed tomography angiography (CTA) studies, 15 were pulmonary CTA (pCTA) and coronary CTA (cCTA) studies, one concerned myocardial perfusion, five studies focused on the thoracic and abdominal aorta, and one investigated renal arteries. Three studies consisted of CT venography (CTV) of the pelvis and lower extremities. Six publications examined the liver, and two focused on the kidney. CONCLUSION: Overall, this review demonstrates that the low tube voltage CT protocol is a powerful tool to reduce the radiation dose in CTA, especially with pCTA and cCTA.


Asunto(s)
Angiografía por Tomografía Computarizada/métodos , Medios de Contraste/administración & dosificación , Dosis de Radiación , Radiografía Abdominal/métodos , Tomografía Computarizada por Rayos X/métodos , Protocolos Clínicos , Medios de Contraste/efectos adversos , Humanos , Exposición a la Radiación/prevención & control , Tomografía Computarizada por Rayos X/efectos adversos
16.
Int J Clin Pract ; 70 Suppl 9B: B29-36, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27577511

RESUMEN

PURPOSE: The aim of this study was to investigate the effect of using low tube voltage, low-concentration contrast media and adaptive statistical iterative reconstruction (ASIR) for reducing the radiation and iodine contrast doses in adrenal and nephrogenic hypertension patients. METHODS AND MATERIALS: A total of 148 hypertension patients who were suspected for adrenal lesions or renal artery stenoses were assigned to two groups and. Group A (n=74) underwent a low tube voltage, low molecular weight dextran enhanced multi-detector row spiral CT (MDCT) (80 kVp, 270 mg I/mL contrast agent), and the raw data were reconstructed with standard filtered back projection (FBP) and ASIR at four different levels of blending (20%, 40%, 60% and 80%, respectively). The control group (Group B, n=74) underwent conventional MDCT (120 kVp, 370 mg I/mL contrast agent), and the data were reconstructed with FBP. The CT values, standard deviation (SD), signal-noise-ratio (SNR) and contrast-noise-ratio (CNR) were measured in the renal vessels, normal adrenal tissue, adrenal neoplasms and subcutaneous fat. The volume CT dose index (CTDIvol ) and dose length product (DLP) were recorded, and an effective dose (ED) was obtained. Two-tailed independent t-tests, paired Chi-square tests and Kappa consistency tests were used for statistical analysis of the data. RESULTS: The CTDIvol , DLP and total iodine dose in group A were decreased by 47.8%, 49.0% and 26.07%, respectively, compared to group B (P<.001). In the qualitative quality analysis, the radiologists rated the 60% ASIR the highest. The mean value of noise (SD) was significantly lower in the 40%, 60% and 80% ASIR-A groups compared with FBP-B for all comparisons. Compared to FBP-B, CNR was significantly higher, with 40%, 60% and 80% ASIR in renal artery stems (P<.05). Compared with FBP-B, a significant increase in the SNR of 40%, 60%, or 80% ASIR was observed in all cases (P<.05). CONCLUSIONS: Compared with conventional protocols, the use of low tube voltage, low-concentration contrast media and 60% ASIR provides similar enhancement and image quality with a reduced radiation dose and contrast iodine dose.


Asunto(s)
Enfermedades de las Glándulas Suprarrenales/diagnóstico por imagen , Medios de Contraste/administración & dosificación , Hipertensión Renovascular/diagnóstico por imagen , Hipertensión/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Adolescente , Enfermedades de las Glándulas Suprarrenales/complicaciones , Adulto , Anciano , Femenino , Humanos , Hipertensión/etiología , Hipertensión Renovascular/etiología , Masculino , Persona de Mediana Edad , Dosis de Radiación , Obstrucción de la Arteria Renal/complicaciones , Obstrucción de la Arteria Renal/diagnóstico por imagen , Relación Señal-Ruido , Tomografía Computarizada Espiral/métodos , Adulto Joven
17.
Nitric Oxide ; 41: 113-9, 2014 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-24887754

RESUMEN

S-Propargyl-L-cysteine (SPRC, also named as ZYZ-802) is a new compound synthesized in our lab. We investigated whether SPRC has exerted protective effects against cardiac hypoxia/re-oxygenation (H/R) and also explored its mechanisms. In our study, isolated ventricular myocytes were subject to a simulated hypoxia solution for 30 min to induce cell injury. Intracellular concentration of Ca(2+) ([Ca(2+)]i) was measured using specific dyes and detected by digital imaging apparatus. Apoptotic cells were evaluated by TUNEL assay. Intervention with SPRC (10 µM) 30 min before hypoxia, can significantly attenuate the apoptosis of isolated papillary muscles resulting from the H/R injury and protect morphology of the muscles. In isolated ventricular myocytes, SPRC considerably improved left ventricular functional recovery. SPRC also suppressed the increase of ([Ca(2+)]i) during hypoxia stage. By measuring the calcium transient of the cell we concluded that SPRC can preserve the RyR and SERCA activities and improve Ca(2+) handling during the H/R. Furthermore, the protective effect of SPRC can be partly blocked by CSE inhibitor PAG.


Asunto(s)
Calcio/metabolismo , Hipoxia de la Célula/efectos de los fármacos , Cisteína/análogos & derivados , Miocitos Cardíacos/efectos de los fármacos , Sustancias Protectoras/farmacología , Animales , Apoptosis/efectos de los fármacos , Forma de la Célula/efectos de los fármacos , Células Cultivadas , Cisteína/farmacología , Espacio Intracelular/metabolismo , Masculino , Miocitos Cardíacos/citología , Miocitos Cardíacos/metabolismo , Oxígeno/metabolismo , Músculos Papilares/citología , Músculos Papilares/efectos de los fármacos , Ratas , Ratas Sprague-Dawley
18.
Insights Imaging ; 15(1): 189, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39090483

RESUMEN

OBJECTIVES: The purpose of this study is to assess the diagnostic efficacy of contrast-enhanced CT scans for small bowel bleeding. METHODS: This retrospective study evaluated patients diagnosed with non-neoplastic small intestinal bleeding (including duodenum) who underwent abdominal CT at our institution from December 2013 to March 2023. Patients were categorized into diverticulum and non-diverticulum groups based on the cause of bleeding. Active bleeding was defined on the CT images as extravasation of contrast material in the intestinal lumen during the arterial phase and/or progressive accumulation of contrast material during the venous phase. We have documented the original report (extracted from the medical record system and additional consultation opinions from senior radiologists), including the presence of active bleeding and its potential bleeding location. Furthermore, two radiologists reassessed the CT images, seeking consensus on the diagnosis between them. RESULTS: The study included 165 patients, predominantly male, with a median age of 30 years. Active bleeding was identified in 48.3% of patients. Notably, all identified bleeding diverticula in the diverticulum group exhibited cul-de-sac termination. Among the identified causes of bleeding, Crohn's disease was most prevalent (46.7%, N of causes = 64). Significant differences were observed in the diagnostic methods between the diverticulum and non-diverticulum groups, with surgery predominantly applied in the diverticulum group, and endoscopy in the non-diverticulum group (n = 49 vs n = 15, p = 0.001). Contrast agent extravasation was significantly higher in the diverticulum group (n = 54 vs n = 16, p = 0.001), and Meckel's diverticulum cases appearing tubular were significantly higher than in other diverticulum cases (n = 25 vs n = 3, p < 0.001). CONCLUSION: CT allows for a higher detection rate of diverticular bleeding, even if asymptomatic, guiding classification into multiple potentially clinically relevant categories. CRITICAL RELEVANCE STATEMENT: Contrast-enhanced CT imaging is effective in determining the location and cause of non-neoplastic small bowel bleeding, especially diverticular bleeding. Therefore, the use of enhanced CT should be prioritized in the diagnosis and management of small bowel bleeding. KEY POINTS: CT has potential value in the diagnosis of small bowel bleeding. CT imaging suggests possible surgical intervention for active bleeding detection. CT diagnoses and localizes small bowel bleeding, aiding in treatment and prioritizing in guidelines.

19.
Insights Imaging ; 15(1): 70, 2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38472526

RESUMEN

OBJECTIVES: To achieve automated quantification of visceral adipose tissue (VAT) distribution in CT images and screen out parameters with discriminative value for inflammatory bowel disease (IBD) subtypes. METHODS: This retrospective multicenter study included Crohn's disease (CD) and ulcerative colitis (UC) patients from three institutions between 2012 and 2021, with patients with acute appendicitis as controls. An automatic VAT segmentation algorithm was developed using abdominal CT scans. The VAT volume, as well as the coefficient of variation (CV) of areas within the lumbar region, was calculated. Binary logistic regression and receiver operating characteristic analysis was performed to evaluate the potential of indicators to distinguish between IBD subtypes. RESULTS: The study included 772 patients (365 CDs, median age [inter-quartile range] = 31.0. (25.0, 42.0) years, 255 males; 241 UCs, 46.0 (34.0, 55.5) years, 138 males; 166 controls, 40.0 (29.0, 53.0) years, 80 males). CD patients had lower VAT volume (CD = 1584.95 ± 1128.31 cm3, UC = 1855.30 ± 1326.12 cm3, controls = 2470.91 ± 1646.42 cm3) but a higher CV (CD = 29.42 ± 15.54 %, p = 0.006 and p ˂ 0.001) compared to UC and controls (25.69 ± 12.61 % vs. 23.42 ± 15.62 %, p = 0.11). Multivariate analysis showed CV was a significant predictor for CD (odds ratio = 6.05 (1.17, 31.12), p = 0.03). The inclusion of CV improved diagnostic efficiency (AUC = 0.811 (0.774, 0.844) vs. 0.803 (0.766, 0.836), p = 0.08). CONCLUSION: CT-based VAT distribution can serve as a potential biomarker for distinguishing IBD subtypes. CRITICAL RELEVANCE STATEMENT: Visceral fat distribution features extracted from CT images using an automated segmentation algorithm (1.14 min) show differences between Crohn's disease and ulcerative colitis and are promising for practical radiological screening. KEY POINTS: • Radiological parameters reflecting visceral fat distribution were extracted for the discrimination of Crohn's disease (CD) and ulcerative colitis (UC). • In CD, visceral fat was concentrated in the lower lumbar vertebrae, and the coefficient of variation was a significant predictor (OR = 6.05 (1.17, 31.12), p = 0.03). • The differences between CD, UC, and controls are promising for practical radiological screening.

20.
Int J Mol Sci ; 14(7): 13093-108, 2013 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-23799362

RESUMEN

The aim of the study was to investigate the protective effects of sodium hydrosulfide (NaHS), a H2S donor, against hypoxia-induced injury in human umbilical vein endothelial cells (HUVECs) and also to look into the possible mechanisms by which H2S exerts this protective effect. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and scratch wound healing assay were chosen to measure the cell viability and migration-promoting effects. The fluorescent probe, DCFH-DA and 5,5',6,6'-Tetrachloro-1,1',3,3'-tetraethyl-imidacarbocyanine iodide (JC-1) were applied to detect the reactive oxygen species (ROS) level and mitochondrial membrane potential (ΔΨm). Furthermore, western blots were used to measure the expressions of the apoptosis-related proteins. Under hypoxic conditions, 300 µM and 600 µM of H2S could protect HUVECs against hypoxia-induced injury, as determined by MTT assay. Following the treatment of 60 µM NaHS for 18 h, scratch wound healing assays indicated that the scratch became much narrower than control group. After treatment with 60 µM, 120 µM, and 600 µM NaHS, and hypoxia for 30 min, flow cytometry demonstrated that the ROS concentrations decreased to 95.08% ± 5.52%, 73.14% ± 3.36%, and 73.51% ± 3.05%, respectively, compared with the control group. In addition, the JC-1 assay showed NaHS had a protective effect on mitochondria damage. Additionally, NaHS increased Bcl-2 expression and decreased the expression of Bax, Caspase-3 and Caspase-9 in a dose-dependent way. Our results suggest that H2S can protect endothelial cells and promote migration under hypoxic condition in HUVECs. These effects are partially associated with the preservation of mitochondrial function mediated by regulating the mitochondrial-dependent apoptotic pathway.


Asunto(s)
Células Endoteliales de la Vena Umbilical Humana , Sulfuro de Hidrógeno , Apoptosis/efectos de los fármacos , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Humanos , Sulfuro de Hidrógeno/metabolismo , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Mitocondrias/metabolismo , Especies Reactivas de Oxígeno/metabolismo
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