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1.
Sci Total Environ ; 928: 172267, 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38583628

RESUMEN

Soils represent crucial sinks for pharmaceuticals and microplastics, making them hotspots for pharmaceuticals and plastic pollution. Despite extensive research on the toxicity of pharmaceuticals and microplastics individually, there is limited understanding of their combined effects on soil biota. This study focused on the earthworm Eisenia fetida as test organism to evaluate the biotoxicity and bioaccumulation of the typical pharmaceutical naproxen and microplastics in earthworms. Results demonstrated that high concentrations of naproxen (100 mg kg-1) significantly increased the malondialdehyde (MDA) content, inducing lipid peroxidation. Even though the low exposure of naproxen exhibits no significant influence to Eisenia fetida, the lipid peroxidation caused by higher concentration than environmental relevant concentrations necessitate attention due to temporal and spatial concentration variability found in the soil environment. Meanwhile, microplastics caused oxidative damage to antioxidant enzymes by reducing the superoxide dismutase (SOD) activity and MDA content in earthworms. Metabolome analysis revealed increased lipid metabolism in naproxen-treated group and reduced lipid metabolism in the microplastic-treated group. The co-exposure of naproxen and microplastics exhibited a similar changing trend to the microplastics-treated group, emphasizing the significant influence of microplastics. The detection of numerous including lipids like 17-Hydroxyandrostane-3-glucuronide, lubiprostone, morroniside, and phosphorylcholine, serves to identify potential biomarkers for naproxen and microplastics exposure. Additionally, microplastics increased the concentration of naproxen in earthworms at sub-organ and subcellular level. This study contributes valuable insights into the biotoxicity and distribution of naproxen and microplastics in earthworms, enhancing our understanding of their combined ecological risk to soil biota.


Asunto(s)
Microplásticos , Naproxeno , Oligoquetos , Contaminantes del Suelo , Oligoquetos/efectos de los fármacos , Naproxeno/toxicidad , Animales , Contaminantes del Suelo/toxicidad , Microplásticos/toxicidad , Ecotoxicología , Suelo/química , Monitoreo del Ambiente
2.
Arterioscler Thromb Vasc Biol ; 44(1): 218-237, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37970714

RESUMEN

BACKGROUND: The formation of large necrotic cores results in vulnerable atherosclerotic plaques, which can lead to severe cardiovascular diseases. However, the specific regulatory mechanisms underlying the development of necrotic cores remain unclear. METHODS: To evaluate how the modes of lesional cell death are reprogrammed during the development of atherosclerosis, the expression levels of key proteins that are involved in the necroptotic, apoptotic, and pyroptotic pathways were compared between different stages of plaques in humans and mice. Luciferase assays and loss-of-function studies were performed to identify the microRNA-mediated regulatory mechanism that protects foamy macrophages from necroptotic cell death. The role of this mechanism in atherosclerosis was determined by using a knockout mouse model with perivascular drug administration and tail vein injection of microRNA inhibitors in Apoe-/- mice. RESULTS: Here, we demonstrate that the necroptotic, rather than the apoptotic or pyroptotic, pathway is more activated in advanced unstable plaques compared with stable plaques in both humans and mice, which closely correlates with necrotic core formation. The upregulated expression of Ripk3 (receptor-interacting protein kinase 3) promotes the C/EBPß (CCAAT/enhancer binding protein beta)-dependent transcription of the microRNA miR-223-3p, which conversely inhibits Ripk3 expression and forms a negative feedback loop to regulate the necroptosis of foamy macrophages. The knockout of the Mir223 gene in bone marrow cells accelerates atherosclerosis in Apoe-/- mice, but this effect can be rescued by Ripk3 deficiency or treatment with the necroptosis inhibitors necrostatin-1 and GSK-872. Like the Mir223 knockout, treating Apoe-/- mice with miR-223-3p inhibitors increases atherosclerosis. CONCLUSIONS: Our study suggests that miR-223-3p expression in macrophages protects against atherosclerotic plaque rupture by limiting the formation of necrotic cores, thus providing a potential microRNA therapeutic candidate for atherosclerosis.


Asunto(s)
Aterosclerosis , MicroARNs , Placa Aterosclerótica , Humanos , Animales , Ratones , Retroalimentación , Aterosclerosis/genética , Aterosclerosis/prevención & control , Aterosclerosis/metabolismo , Placa Aterosclerótica/metabolismo , Macrófagos/metabolismo , Necrosis/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Ratones Noqueados , Apolipoproteínas E , Ratones Endogámicos C57BL , Proteína Serina-Treonina Quinasas de Interacción con Receptores/genética , Proteína Serina-Treonina Quinasas de Interacción con Receptores/metabolismo
3.
Sci Total Environ ; 867: 161169, 2023 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-36581266

RESUMEN

Due to the strict rules and restrictions on the utilization of bisphenol A (BPA) around the world, an emerging endocrine disrupting chemical, bisphenol S (BPS) has been widely utilized as a substitute and frequently detected in the environment, even in the human body. Although it has been widely studied in the aquatic systems, the fate and toxicological effect of BPS in soil invertebrates are poorly known. This study presented a comprehensive exploration into the attenuation, bioaccumulation, and physiological distribution of BPS in an ecologically significant soil invertebrate, as well as its subsequent ecotoxicological effect to earthworm for the first time. The E. fetida could promote the BPS attenuation in soil, with degradation rates of 92.8 ± 1.6 % and 98.6 ± 1.1 % at dosage of 1.0 mg/kg dry weight soil (DWS) and 0.1 mg/kg DWS, respectively. The bioaccumulation of BPS in the earthworm was up to 111.6 ± 6.0 mg/kg lipid and 12.9 ± 2.9 mg/kg lipid with the initial dosage of 1.0 mg/kg DWS and 0.1 mg/kg DWS, respectively. Furthermore, BPS could induce oxidative stress and the process of antioxidant defense in earthworm cells at relatively high dose (1.0 mg/kg DWS and 10.0 mg/kg DWS), suggesting potential risks of BPS to the soil environment. This study could contribute to a more in-depth understanding of the fate of BPS in soil-earthworm system, and indicate a necessity for better understanding the environmental fate and ecological risks of BPA substitutes in the future.


Asunto(s)
Oligoquetos , Contaminantes del Suelo , Animales , Humanos , Bioacumulación , Contaminantes del Suelo/análisis , Suelo , Lípidos
4.
Front Genet ; 13: 1035337, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36568377

RESUMEN

Background: N-Alpha-Acetyltransferase 50 (NAA50) has acetyltransferase activity and is important for chromosome segregation. However, the function and mechanism of NAA50 expression in cancer development was still unclear. Here, we systematically researched the function and mechanism of NAA50 in pan-cancer, and further verified the results of NAA50 in lung adenocarcinoma (LUAD). Methods: In this study, using the online databases TIMER2.0, SangerBox3.0, HPA, UCSC, GEPIA, cBioPortal, UALCAN, TISIDB, CancerSEA and LinkedOmics, we focused on the relevance between NAA50 and oncogenesis, progression, methylation, immune infiltration, function and prognosis. In addition, the proliferation of cells was detected by CCK-8 and Edu assay. Finally, we analyzed the relationship between the expression of NAA50 and cell cycle related proteins. Results: Pan-cancer analysis indicated that NAA50 was overexpressed in most cancers. And there was a significant correlation between NAA50 expression and the prognosis of cancer patients. In the meantime, NAA50 gene changes occur in a variety of tumors. Compared with normal tissues, the methylation level of NAA50 promoter increased in most cancer tissues. In addition, the results exhibited that in most cancers, NAA50 was significantly positively correlated with bone myeloid-derived suppressor cell (MDSC) infiltration and negatively correlated with T cell NK infiltration. Moreover, functional enrichment indicated that NAA50 regulates cell cycle and proliferation in LUAD. In vitro experiments testified that knockout of NAA50 could significantly inhibit the proliferation of LUAD. Conclusion: NAA50 may be a potential biomarker and oncogene of pan-cancer, especially LUAD, which may promote the occurrence and development of tumors through different mechanisms. Furthermore, NAA50 was bound up with to immune cell infiltration in pan-cancer, meaning NAA50 may be an important therapeutic target for human cancers.

5.
Eur J Histochem ; 64(s2)2020 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-32705857

RESUMEN

Our objectives are to demonstrate whether the kynurenine pathway is activated in diarrhea-type irritable bowel syndrome (IBS-D) patients, and whether the neurotoxic metabolite quinolinic acid (QUIN) is out of balance with the neuroprotective metabolite kynurenic acid (KYNA), and further explore whether this can lead to increase of N-methyl D-aspartate receptor 2B (NMDAR2B) expression in the enteric nervous system and in turn leads to intestinal symptoms and mood disorders. All enrolled healthy controls and patients accepted IBS symptom severity scale (IBS-SSS) score, Self-rating Depression Scale (SDS) and Self-rating Anxiety Scale (SAS) anxiety and depression scores, and also underwent colonoscopy to collect ileum and colonic mucosa specimens. The expression of NMDAR2B in intestinal mucosa was detected by immunofluorescence, and fasting serum was collected to detect the tryptophan (Trp), kynurenine (KYN), KYNA and QUIN by high performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS). Our results showed that the kynurenine pathway of IBS-D patients was activated. The production of QUIN and KYNA was imbalanced and resulting in an increased NMDAR2B for patients with IBS-D, which may be involved in intestinal symptoms and mood disorders of IBS-D.


Asunto(s)
Diarrea/metabolismo , Síndrome del Colon Irritable/metabolismo , Quinurenina/metabolismo , Diarrea/sangre , Femenino , Humanos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patología , Síndrome del Colon Irritable/sangre , Síndrome del Colon Irritable/patología , Ácido Quinurénico/sangre , Ácido Quinurénico/metabolismo , Masculino , Ácido Quinolínico/sangre , Ácido Quinolínico/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo
6.
IEEE Trans Biomed Eng ; 66(10): 2945-2951, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-30762524

RESUMEN

OBJECTIVE: The purpose of the present study was to achieve submillimeter-level diffusion tensor imaging (DTI) of the macaque brain by using diffusion weighted (DW) readout-segmented echo planar imaging (rsEPI) with an optimized protocol at 7 T MRI. METHODS: Three anesthetized macaques were included in this study. Under different scan settings, we compared the signal-to-noise ratio (SNR) and geometric distortion of DW images, implemented an optimized protocol for submillimeter-level DTI acquisition, and evaluated its performance. RESULTS: The parallel-imaging-enabled (in GRAPPA mode) monopolar or monopolar+ diffusion scheme has higher SNR versus bipolar scheme, whereas trivial differences in SNR and image geometric distortion occurred when using increased readout segments with monopolar and monopolar+ that did not reach statistical significance. Submillimeter-level (0.8 mm isotropic) DTI data provide a sharper delineation of white matter contour than the 1 mm level. CONCLUSION: The rsEPI technique with parallel imaging enabled, and with the shortest readout segments in conjunction with monopolar/monopolar+ diffusion encoding scheme, may be optimal for submillimeter-level diffusion imaging over macaque brains in vivo. SIGNIFICANCE: rsEPI could effectively merit high-resolution DTI for in vivo macaque brain submillimeter structural architecture investigations at ultrahigh fields.


Asunto(s)
Encéfalo/diagnóstico por imagen , Imagen de Difusión por Resonancia Magnética/métodos , Imagen Eco-Planar/métodos , Aumento de la Imagen/métodos , Animales , Procesamiento de Imagen Asistido por Computador , Macaca , Relación Señal-Ruido
7.
Invest Radiol ; 52(9): 529-537, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28430716

RESUMEN

PURPOSE: We prospectively quantified the signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) of integrated parallel acquisition technique (PAT) and simultaneous multislice (SMS) acceleration and various combinations thereof, and we further compared two 4-fold-accelerated (PAT2-SMS2) high-resolution turbo spin echo (TSE) magnetic resonance imaging (MRI) protocols of the knee against a clinical 2-fold-accelerated (PAT2-SMS1) TSE standard. MATERIALS AND METHODS: Institutional review board approval was obtained, and all subjects gave informed consent. Fourteen knee MRI examinations were obtained (8 men, 6 women; mean age, 46 years; age range, 28-62 years) using a 3 T MRI system and a TSE pulse sequence prototype that allowed for the combination of PAT and SMS acceleration. Predicted whole-body specific absorption rates were recorded for all pulse sequences. For quantitative analysis, the difference method was used to calculate SNR and CNR analysis of 6 different TSE acceleration schemes (PAT2-SMS1, PAT3-SMS1, PAT1-SMS2, PAT1-SMS3, PAT2-SMS2, and PAT2-SMS3). For qualitative analysis, sagittal intermediate-weighted and axial fat-suppressed T2-weighted MR images were obtained with PAT2-SMS1 and PAT2-SMS2 acceleration schemes using similar parameters. One faster PAT2-SMS2 acceleration scheme with decreased repetition time and longer echo train was labeled with the addition SPEED for the purpose of this report. Two readers rated the data sets for image quality, structural visibility, and overall observer satisfaction using equidistant 5-point Likert scales. Readers additionally noted the presence of cartilage defects, meniscal tears, tendons and ligament tears, and bone marrow edema pattern. Friedman and Kruskal-Wallis tests were used. P values of less than 0.01 were considered significant. RESULTS: All pulse sequences were successfully executed and reconstructed inline. Whole-body specific absorption rates ranged between 1.4 and 3.9 W/kg for all acquisitions and remained within mandated limits. Quantitatively, mean SNR and CNR were significantly higher for SMS than those for PAT and similar for PAT2-SMS2 and PAT2-SMS1. Fluid was brightest on PAT2-SMS1, whereas noise, edge sharpness, contrast resolution, and fat suppression were similar on PAT2-SMS1 and SMS2-PAT2 and mildly inferior on PAT2-SMS2 SPEED. Articular cartilage received mildly higher ratings on PAT2-SMS1, whereas visibility of menisci was mildly inferior on PAT2-SMS2 SPEED. Observer preferences were similarly high for PAT2-SMS1 and PAT2-SMS2 and mildly inferior for the faster PAT2-SMS2 SPEED images. Four cartilage defects and 2 meniscal tears were seen by both readers on all sequences. CONCLUSIONS: We demonstrate the signal preservation capabilities of SMS over PAT acceleration, which allow for similar SNR and CNR of 4-fold PAT2-SMS2 and 2-fold PAT2-SMS1 acceleration. Four-fold-accelerated TSE through the combination of PAT2 and SMS2 enables approximately 50% shorter acquisition times compared with regular PAT2 acceleration, similar quantitative and qualitative image quality, and holds promise for a meaningful increase of the efficiency of clinical 2-dimensional MRI of the knee.


Asunto(s)
Artropatías/diagnóstico por imagen , Traumatismos de la Rodilla/diagnóstico por imagen , Articulación de la Rodilla/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Adulto , Cartílago Articular/diagnóstico por imagen , Cartílago Articular/patología , Femenino , Humanos , Artropatías/patología , Traumatismos de la Rodilla/patología , Articulación de la Rodilla/patología , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Reproducibilidad de los Resultados , Relación Señal-Ruido
8.
China Journal of Endoscopy ; (12): 91-94, 2017.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-660958

RESUMEN

Objective To evaluated the security of endoscopic retrograde cholangiopancreatography (ERCP) among the patients aged over 80 years. Methods 80 patients who were accepted ERCP and aged over 80 years were analgzed, to learn the diseases of patients and evaluate what the impact of ERCP. To complete ERCP in the shortest time, we observed of vital signs, abdominal symptoms and nasal biliary drainage rigorouly after the opration , and to test blood routine, serum amylase, urine amylase and biochemical indicators, detect whether secondary or aggravate other organs damage within 1 week. Results There were 11 cases (13.75%) had secondary organs damage, the percentage of with over two diseases is 51.25%, 78 cases (96.25%) accepted the ERCP, the primary success rate of lithotomy in 55 cases of common bile duct stones is 74.55%, among them there were 3 cases accepted internal drainage by cutting the nasobiliary since they can not be conducted lithotomy once more. One patient of pancreatic carcinoma complicated with duodenal stenosis was treated in implantation of biliary metal stent after accepted the dilation of bile duct , and then the stent was implanted in the narrow duodenum. One patient was died of heart failure, renal failure and respiratory failure after one week; There were no other serious complications occurred, the total incidence rate of complication was 7.50%, the average operation time was (26.64 ± 8.31) min. Conclusions The patients over 80 years old are relatively safe for ERCP, the effect is obviously, and appropriate management of perioperative can reduce the incidence of complications.

9.
China Journal of Endoscopy ; (12): 91-94, 2017.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-658163

RESUMEN

Objective To evaluated the security of endoscopic retrograde cholangiopancreatography (ERCP) among the patients aged over 80 years. Methods 80 patients who were accepted ERCP and aged over 80 years were analgzed, to learn the diseases of patients and evaluate what the impact of ERCP. To complete ERCP in the shortest time, we observed of vital signs, abdominal symptoms and nasal biliary drainage rigorouly after the opration , and to test blood routine, serum amylase, urine amylase and biochemical indicators, detect whether secondary or aggravate other organs damage within 1 week. Results There were 11 cases (13.75%) had secondary organs damage, the percentage of with over two diseases is 51.25%, 78 cases (96.25%) accepted the ERCP, the primary success rate of lithotomy in 55 cases of common bile duct stones is 74.55%, among them there were 3 cases accepted internal drainage by cutting the nasobiliary since they can not be conducted lithotomy once more. One patient of pancreatic carcinoma complicated with duodenal stenosis was treated in implantation of biliary metal stent after accepted the dilation of bile duct , and then the stent was implanted in the narrow duodenum. One patient was died of heart failure, renal failure and respiratory failure after one week; There were no other serious complications occurred, the total incidence rate of complication was 7.50%, the average operation time was (26.64 ± 8.31) min. Conclusions The patients over 80 years old are relatively safe for ERCP, the effect is obviously, and appropriate management of perioperative can reduce the incidence of complications.

10.
NMR Biomed ; 28(10): 1332-44, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26332290

RESUMEN

The performance of multichannel transmit coil layouts and parallel transmission (pTx) RF pulse design was evaluated with respect to transmit B1 (B1 (+)) homogeneity and specific absorption rate (SAR) at 3 T for a whole body coil. Five specific coils were modeled and compared: a 32-rung birdcage body coil (driven either in a fixed quadrature mode or a two-channel transmit mode), two single-ring stripline arrays (with either 8 or 16 elements), and two multi-ring stripline arrays (with two or three identical rings, stacked in the z axis and each comprising eight azimuthally distributed elements). Three anatomical targets were considered, each defined by a 3D volume representative of a meaningful region of interest (ROI) in routine clinical applications. For a given anatomical target, global or local SAR controlled pTx pulses were designed to homogenize RF excitation within the ROI. At the B1 (+) homogeneity achieved by the quadrature driven birdcage design, pTx pulses with multichannel transmit coils achieved up to about eightfold reduction in local and global SAR. When used for imaging head and cervical spine or imaging thoracic spine, the double-ring array outperformed all coils, including the single-ring arrays. While the advantage of the double-ring array became much less pronounced for pelvic imaging, with a substantially larger ROI, the pTx approach still provided significant gains over the quadrature birdcage coil. For all design scenarios, using the three-ring array did not necessarily improve the RF performance. Our results suggest that pTx pulses with multichannel transmit coils can reduce local and global SAR substantially for body coils while attaining improved B1 (+) homogeneity, particularly for a "z-stacked" double-ring design with coil elements arranged on two transaxial rings.


Asunto(s)
Imagen por Resonancia Magnética/instrumentación , Algoritmos , Simulación por Computador , Diseño de Equipo , Humanos , Modelos Teóricos , Programas Informáticos
11.
Neuroimage ; 106: 170-81, 2015 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-25462690

RESUMEN

Multi-band echo planar imaging (MB-EPI), a new approach to increase data acquisition efficiency and/or temporal resolution, has the potential to overcome critical limitations of standard acquisition strategies for obtaining high-resolution whole brain perfusion imaging using arterial spin labeling (ASL). However, the use of MB also introduces confounding effects, such as spatially varying amplified thermal noise and leakage contamination, which have not been evaluated to date as to their effect on cerebral blood flow (CBF) estimation. In this study, both the potential benefits and confounding effects of MB-EPI were systematically evaluated through both simulation and experimentally using a pseudo-continuous arterial spin labeling (pCASL) strategy. These studies revealed that the amplified noise, given by the geometry factor (g-factor), and the leakage contamination, assessed by the total leakage factor (TLF), have a minimal impact on CBF estimation. Furthermore, it is demonstrated that MB-EPI greatly benefits high-resolution whole brain pCASL studies in terms of improved spatial and temporal signal-to-noise ratio efficiencies, and increases compliance with the assumptions of the commonly used single blood compartment model, resulting in improved CBF estimates.


Asunto(s)
Artefactos , Velocidad del Flujo Sanguíneo/fisiología , Encéfalo/fisiología , Circulación Cerebrovascular/fisiología , Imagen Eco-Planar/métodos , Angiografía por Resonancia Magnética/métodos , Adulto , Algoritmos , Encéfalo/anatomía & histología , Simulación por Computador , Femenino , Humanos , Aumento de la Imagen/métodos , Interpretación de Imagen Asistida por Computador/métodos , Masculino , Persona de Mediana Edad , Modelos Cardiovasculares , Modelos Neurológicos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
12.
Radiology ; 272(2): 587-97, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24678859

RESUMEN

PURPOSE: To investigate the predictive value of transcatheter intraarterial perfusion (TRIP) magnetic resonance (MR) imaging-measured tumor perfusion changes during transarterial chemoembolization on transplant-free survival (TFS) in patients with unresectable hepatocellular carcinoma (HCC). MATERIALS AND METHODS: This HIPAA-compliant prospective study was approved by the institutional review board. Written informed consent was obtained from all patients. Fifty-one consecutive adult patients with surgically unresectable single or multifocal measurable HCC and adequate laboratory parameters who underwent chemoembolization in a combined MR imaging-interventional radiology suite between February 2006 and June 2010 were studied. Tumor perfusion changes during chemoembolization were measured by using TRIP MR imaging with area under the time-signal intensity curve calculation. The end point of the study was TFS. The authors assessed the correlation between the percentage perfusion reduction in the tumor during chemoembolization and TFS by using univariate and multivariate analyses. RESULTS: Fifty patients (mean age, 61 years; 39 men aged 42-87 years [mean age, 61 years] and 11 women aged 49-83 years [mean age, 62 years]) were eligible for the analysis. Patients with 35%-85% intraprocedural tumor area under the time-signal intensity curve reduction (n = 32) showed significantly improved median TFS compared with patients with an area under the time-signal intensity curve reduction outside this range (n = 18) (16.6 months [95% confidence interval: 11.2, 22.0 months] vs 9.3 months [95% confidence interval: 6.6, 12.0 months], respectively; P = .046; hazard ratio: 0.46; 95% confidence interval: 0.21, 1.00). The cumulative TFS rates in the 35%-85% and less than 35% or more than 85% perfusion reduction groups at 1, 2, and 5 years after chemoembolization were 66.4%, 42.2%, and 28.2% versus 33.8%, 16.9%, and 0%, respectively. CONCLUSION: The study shows evidence of an association between intraprocedural tumor perfusion reduction during chemoembolization and TFS and suggests the utility of TRIP MR imaging- measured tumor perfusion reduction as an intraprocedural imaging biomarker during chemoembolization.


Asunto(s)
Carcinoma Hepatocelular/terapia , Quimioembolización Terapéutica/métodos , Neoplasias Hepáticas/terapia , Angiografía por Resonancia Magnética/métodos , Imagen por Resonancia Magnética Intervencional , Adulto , Anciano , Anciano de 80 o más Años , Angiografía de Substracción Digital , Antineoplásicos/administración & dosificación , Biomarcadores , Biopsia , Medios de Contraste/administración & dosificación , Femenino , Gadolinio DTPA/administración & dosificación , Humanos , Pruebas de Función Hepática , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Prospectivos , Tasa de Supervivencia , Resultado del Tratamiento , Carga Tumoral
13.
Magn Reson Med ; 70(5): 1210-9, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24038314

RESUMEN

PURPOSE: Higher signal to noise ratio (SNR) and improved contrast have been demonstrated at ultra-high magnetic fields (≥7 Tesla [T]) in multiple targets, often with multi-channel transmit methods to address the deleterious impact on tissue contrast due to spatial variations in B1 (+) profiles. When imaging the heart at 7T, however, respiratory and cardiac motion, as well as B0 inhomogeneity, greatly increase the methodological challenge. In this study we compare two-spoke parallel transmit (pTX) RF pulses with static B1 (+) shimming in cardiac imaging at 7T. METHODS: Using a 16-channel pTX system, slice-selective two-spoke pTX pulses and static B1 (+) shimming were applied in cardiac CINE imaging. B1 (+) and B0 mapping required modified cardiac triggered sequences. Excitation homogeneity and RF energy were compared in different imaging orientations. RESULTS: Two-spoke pulses provide higher excitation homogeneity than B1 (+) shimming, especially in the more challenging posterior region of the heart. The peak value of channel-wise RF energy was reduced, allowing for a higher flip angle, hence increased tissue contrast. Image quality with two-spoke excitation proved to be stable throughout the entire cardiac cycle. CONCLUSION: Two-spoke pTX excitation has been successfully demonstrated in the human heart at 7T, with improved image quality and reduced RF pulse energy when compared with B1 (+) shimming.


Asunto(s)
Algoritmos , Contencion de la Respiración , Técnicas de Imagen Sincronizada Cardíacas/métodos , Corazón/anatomía & histología , Aumento de la Imagen/métodos , Interpretación de Imagen Asistida por Computador/métodos , Imagen por Resonancia Cinemagnética/métodos , Diseño de Equipo , Análisis de Falla de Equipo , Estudios de Factibilidad , Humanos , Aumento de la Imagen/instrumentación , Interpretación de Imagen Asistida por Computador/instrumentación , Ondas de Radio , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Procesamiento de Señales Asistido por Computador/instrumentación
14.
Neuroimage ; 80: 80-104, 2013 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-23702417

RESUMEN

The Human Connectome Project (HCP) relies primarily on three complementary magnetic resonance (MR) methods. These are: 1) resting state functional MR imaging (rfMRI) which uses correlations in the temporal fluctuations in an fMRI time series to deduce 'functional connectivity'; 2) diffusion imaging (dMRI), which provides the input for tractography algorithms used for the reconstruction of the complex axonal fiber architecture; and 3) task based fMRI (tfMRI), which is employed to identify functional parcellation in the human brain in order to assist analyses of data obtained with the first two methods. We describe technical improvements and optimization of these methods as well as instrumental choices that impact speed of acquisition of fMRI and dMRI images at 3T, leading to whole brain coverage with 2 mm isotropic resolution in 0.7 s for fMRI, and 1.25 mm isotropic resolution dMRI data for tractography analysis with three-fold reduction in total dMRI data acquisition time. Ongoing technical developments and optimization for acquisition of similar data at 7 T magnetic field are also presented, targeting higher spatial resolution, enhanced specificity of functional imaging signals, mitigation of the inhomogeneous radio frequency (RF) fields, and reduced power deposition. Results demonstrate that overall, these approaches represent a significant advance in MR imaging of the human brain to investigate brain function and structure.


Asunto(s)
Encéfalo/anatomía & histología , Encéfalo/fisiología , Conectoma/métodos , Imagen de Difusión por Resonancia Magnética/métodos , Modelos Neurológicos , Red Nerviosa/anatomía & histología , Red Nerviosa/fisiología , Animales , Humanos , Aumento de la Imagen/métodos , Modelos Anatómicos , Análisis Espacio-Temporal
15.
AJR Am J Roentgenol ; 198(5): 1196-202, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22528913

RESUMEN

OBJECTIVE: To our knowledge there is currently no quantitative preprocedural method for predicting the distribution and selectivity of delivery of chemoembolic material during trans-arterial chemoembolization. Transcatheter intraarterial perfusion MRI has been developed as a method of quantifying hepatic arterial perfusion. The purpose of this study was to investigate whether findings at transcatheter intraarterial perfusion MRI before chemoembolization can be used to predict uptake of the chemoembolic material delivered during chemoembolization. SUBJECTS AND METHODS: We compared quantitative prechemoembolization transcatheter intraarterial perfusion MRI parameters with analogous postchemoembolization CT chemoembolic distribution parameters and analyzed correlation using the Pearson correlation coefficient. These MRI and CT parameters included volume of distribution (a metric for volumetric liver perfusion or therapeutic agent delivery) and chemoembolic delivery selectivity factor (a ratio of volume-normalized tumor to background signal intensity that indicates the selectivity of chemoembolic delivery). RESULTS: Twenty-four hepatocellular carcinomas were targeted in 18 patients (14 men, four women; mean age, 66 years), and segmental or lobar chemoembolization with intraprocedural transcatheter intraarterial perfusion MRI was successful in all 18. Transcatheter intraarterial perfusion MRI and CT volume of distribution did not differ significantly (MRI, 233 cm(3); CT, 235 cm(3); p = 0.857). Transcatheter intraarterial perfusion MRI selectivity factor was an underestimate of CT selectivity factor (MRI, 0.20; CT, 0.25; p = 0.005). Prechemoembolization transcatheter intraarterial perfusion MRI and postchemoembolization CT volume of distribution (r = 0.93; p < 0.001) and selectivity factor (r = 0.95; p < 0.001) showed significant correlation. CONCLUSION: Tumor perfusion measured with transcatheter intraarterial perfusion MRI is predictive of uptake of chemoembolic material before delivery. This MRI technique may have utility as a method of quantifying delivery of the therapeutic agent during chemoembolization and, potentially, other liver-directed locoregional therapies.


Asunto(s)
Carcinoma Hepatocelular/terapia , Quimioembolización Terapéutica/métodos , Neoplasias Hepáticas/terapia , Angiografía por Resonancia Magnética/métodos , Anciano , Carcinoma Hepatocelular/patología , Cateterismo , Cisplatino/administración & dosificación , Medios de Contraste/administración & dosificación , Doxorrubicina/administración & dosificación , Aceite Etiodizado/administración & dosificación , Femenino , Gadolinio DTPA , Humanos , Interpretación de Imagen Asistida por Computador , Yohexol/administración & dosificación , Modelos Lineales , Neoplasias Hepáticas/patología , Masculino , Microesferas , Mitomicina/administración & dosificación , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
16.
AJR Am J Roentgenol ; 197(5): 1237-43, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22021520

RESUMEN

OBJECTIVE: The purpose of this study was to test the hypothesis that subjective angiographic endpoints during transarterial chemoembolization (TACE) of hepatocellular carcinoma are consistent and correlate with objective intraprocedural reductions in tumor perfusion determined with quantitative 4D transcatheter intraarterial perfusion MRI. SUBJECTS AND METHODS: In this prospective study, 18 consecutively registered patients underwent TACE in a combined MRI-interventional radiology suite. Three board-certified interventional radiologists independently graded the angiographic endpoint of each procedure using a previously described subjective angiographic chemoembolization endpoint scale. A consensus endpoint rating was established for each patient. Patients underwent quantitative 4D transcatheter intraarterial perfusion MRI immediately before and after TACE, and mean whole tumor perfusion was calculated from the images. Consistency of subjective angiographic endpoint ratings between observers was evaluated with the intraclass correlation coefficient. The relation between the endpoint ratings and intraprocedural transcatheter intraarterial perfusion MRI changes was evaluated with the Spearman rank correlation coefficient. RESULTS: The subjective angiographic chemoembolization endpoint rating scale showed very good consistency among all observers (intraclass correlation coefficient, 0.80). The consensus endpoint rating correlated significantly with both absolute (r = 0.54, p = 0.022) and percentage (r = 0.85, p < 0.001) reduction in intraprocedural perfusion. CONCLUSION: The subjective angiographic chemoembolization endpoint rating scale shows very good consistency between raters and significantly correlates with objectively measured intraprocedural perfusion reductions during TACE. These results support the use of the scale as a standardized alternative method in quantitative 4D transcatheter intraarterial perfusion MRI to classify patients on the basis of embolic endpoints of TACE.


Asunto(s)
Angiografía/métodos , Carcinoma Hepatocelular/terapia , Quimioembolización Terapéutica/métodos , Neoplasias Hepáticas/terapia , Angiografía por Resonancia Magnética/métodos , Radiografía Intervencional/métodos , Carcinoma Hepatocelular/diagnóstico por imagen , Determinación de Punto Final , Femenino , Humanos , Neoplasias Hepáticas/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Resultado del Tratamiento
17.
J Magn Reson Imaging ; 34(3): 563-9, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21761464

RESUMEN

PURPOSE: To investigate the hypothesis that four-dimensional (4D) transcatheter intraarterial perfusion (TRIP) magnetic resonance imaging (MRI) can quantify immediate perfusion changes after radiofrequency (RF) ablation in rabbit VX2 liver tumors. MATERIALS AND METHODS: Nine New Zealand White rabbits were used to surgically implant VX2 liver tumors. During ultrasound-guided RF ablation, tumors received either a true or sham ablation. After selective catheterization of the left hepatic artery under x-ray fluoroscopy, we acquired pre- and post-RF ablation 4D TRIP MR images using 3 mL of 2.5% intraarterial gadopentetate dimeglumine. Two regions-of-interest were drawn upon each tumor to generate signal-intensity time curves. Area under the curve (AUC) was calculated to provide semiquantitative perfusion measurements that were compared using a paired t-test (α = 0.05). Ablated tissue was visually confirmed on pathology using Evans blue dye. RESULTS: Mean AUC perfusion of VX2 tumors for the true ablation group decreased by 92.0% (95% confidence interval [CI]: 83.3%-100%), from 1913 (95% CI: 1557, 2269) before RF ablation to 76.6 (95% CI: 18.4, 134.8) after RF ablation (a.u., P < 0.001). Sham-ablated tumors demonstrated no significant perfusion changes. CONCLUSION: 4D TRIP MRI can quantify liver tumor perfusion reductions in VX2 rabbits after RF ablation. This MRI technique can potentially be used to improve tumor response assessment at the time of RF ablation.


Asunto(s)
Interpretación de Imagen Asistida por Computador/métodos , Imagenología Tridimensional/métodos , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/cirugía , Angiografía por Resonancia Magnética/métodos , Técnicas de Imagen Sincronizada Respiratorias/métodos , Cirugía Asistida por Computador/métodos , Algoritmos , Animales , Línea Celular Tumoral , Femenino , Aumento de la Imagen/métodos , Conejos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Resultado del Tratamiento
18.
Acad Radiol ; 18(7): 828-36, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21669349

RESUMEN

RATIONALE AND OBJECTIVES: To prospectively test the hypothesis that transcatheter intraarterial perfusion magnetic resonance imaging (TRIP-MRI) measured semiquantitative perfusion reductions during transcatheter arterial chemoembolization of hepatocellular carcinoma (HCC) are associated with tumor response. MATERIALS AND METHODS: Twenty-eight patients (mean age 63 years; range 47-87 years) with 29 tumors underwent chemoembolization in a combined magnetic resonance interventional radiology suite. Intraprocedural tumor perfusion reductions during chemoembolization were monitored using TRIP-MRI. Pre- and postchemoembolization semiquantitative area under the time-signal enhancement curve (AUC) tumor perfusion was measured. Mean tumor perfusion pre- and postchemoembolization were compared using a paired t-test. Imaging follow-up was performed 1-3 months after chemoembolization. We studied the relationship between short-term tumor imaging response and intraprocedural perfusion reductions using univariate and multivariate analysis. RESULTS: Intraprocedural AUC perfusion value decreased significantly after chemoembolization (342.1 vs. 158.6 arbitrary unit, P < .001). Twenty-six patients with 27 HCCs (n = 27) had follow-up imaging at mean 39 days postchemoembolization. Favorable response was present in 67% of these treated tumors according to necrosis criteria. Fifteen of 16 (94%) tumors with 25%-75% perfusion reductions showed necrosis treatment response compared to only 3 of 11 (27%) tumors with perfusion reductions outside the above range (P = .001). Multivariate logistic regression indicated that intraprocedural tumor perfusion reduction and Child-Pugh class were independent factors associated significantly with tumor response (P = .012 and .047, respectively). CONCLUSION: TRIP-MRI can successfully measure semiquantitative changes in HCC perfusion during chemoembolization. Intraprocedural tumor perfusion reductions are associated with future tumor response.


Asunto(s)
Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/terapia , Quimioembolización Terapéutica/métodos , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/terapia , Angiografía por Resonancia Magnética/métodos , Imagen por Resonancia Magnética Intervencional/métodos , Adulto , Anciano , Cateterismo/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Resultado del Tratamiento
19.
Magn Reson Imaging ; 29(8): 1131-7, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21705167

RESUMEN

PURPOSE: The aim of this study was to develop a targeted volumetric radiofrequency field (B(1)(+)) mapping technique to provide region-of-interest B(1)(+) information. MATERIALS AND METHODS: Targeted B(1)(+) maps were acquired using three-dimensional (3D) reduced field-of-view (FOV) inner-volume turbo spin echo-catalyzed double-angle method (DAM). Targeted B(1)(+) maps were compared with full-FOV B(1)(+) maps acquired using 3D catalyzed DAM in a phantom and in the brain of a healthy volunteer. In addition, targeted volumetric abdomeninal B(1)(+) mapping was demonstrated in the abdomen of another healthy volunteer. RESULTS: The targeted reduced-FOV images demonstrated no aliasing artifacts in all experiments. Close match between targeted B(1)(+) map and reference full-FOV B(1)(+) map in the same region was observed, with percentage root-mean-squared error <0.4% in the phantom and <0.8% in the healthy volunteer brain. The abdominal B(1)(+) maps showed small B(1)(+) variation in the kidneys and liver from the healthy volunteer. CONCLUSION: The proposed 3D reduced-FOV catalyzed DAM provides a rapid, simple and accurate method for targeted volumetric B(1)(+) mapping and can be easily implemented for applications related to radiofrequency field mapping in small targeted regions.


Asunto(s)
Encéfalo/patología , Imagenología Tridimensional/métodos , Artefactos , Mapeo Encefálico/métodos , Humanos , Riñón/patología , Hígado/patología , Imagen por Resonancia Magnética/métodos , Modelos Anatómicos , Fantasmas de Imagen , Ondas de Radio , Reproducibilidad de los Resultados
20.
AJR Am J Roentgenol ; 196(4): 919-28, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21427346

RESUMEN

OBJECTIVE: The purpose of this study was to investigate the relation between angiographic embolic endpoints of transarterial chemoembolization (TACE) and the survival of patients with hepatocellular carcinoma (HCC). MATERIALS AND METHODS: This study was a retrospective assessment of the cases of 105 patients with surgically unresectable HCC who underwent TACE. The cases were classified according to a previously established subjective angiographic chemoembolization endpoint scale. Only one patient had endpoint level I embolization and was excluded from all subsequent analysis. Survival was evaluated with Kaplan-Meier analysis. The Cox proportional hazards model was used to determine independent prognostic risk factors of survival. RESULTS: The overall median survival period was 21.1 months (95% CI, 15.9-26.4 months). Patients with embolization to subjective angiographic chemoembolization endpoint levels II and III were aggregated and had a significantly longer median survival period (25.6 months; 95% CI, 16.2-35.0 months) than patients with embolization to level IV (17.1 months; 95% CI, 13.3-20.9 months) (p = 0.035). The results of multivariate analysis indicated that all of the following factors were independent negative prognostic indicators of survival: subjective angiographic chemoembolization endpoint level IV (hazard ratio [HR], 2.49; 95% CI, 1.41-4.42; p = 0.002), European Cooperative Oncology Group performance status greater than 0 (HR, 1.97; 95% CI, 1.15-3.37; p = 0.013), American Joint Committee on Cancer stage III or IV (HR, 2.42; 95% CI, 1.27-4.60; p = 0.007), and Child-Pugh class B (HR, 1.94; 95% CI, 1.09-3.46; p = 0.025). CONCLUSION: Embolization to an intermediate, substasis endpoint (subjective angiographic chemoembolization endpoint levels II and III) during TACE improves survival compared with embolization to a higher, stasis endpoint (level IV). Interventional oncologists should consider aiming for these intermediate, substasis angiographic endpoints during TACE.


Asunto(s)
Carcinoma Hepatocelular/terapia , Quimioembolización Terapéutica/métodos , Neoplasias Hepáticas/terapia , Anciano , Análisis de Varianza , Angiografía de Substracción Digital , Determinación de Punto Final , Femenino , Humanos , Masculino , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Estudios Retrospectivos , Factores de Riesgo , Tasa de Supervivencia
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