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1.
Zhonghua Xin Xue Guan Bing Za Zhi ; 48(11): 922-929, 2020 Nov 24.
Artigo em Chinês | MEDLINE | ID: mdl-33210863

RESUMO

Objective: To investigate the distribution pattern of late gadolinium enhancement (LGE) in left ventricular free wall of patients with dilated cardiomyopathy (DCM). Methods: A total of 130 consecutive DCM patients who were hospitalized in our hospital, underwent both CMR and CTA examinations and met the inclusion and exclusion criteria including negative results of coronary angiography or coronary CTA, were retrospective included in this study. The LGE pattern, extent and distribution in left ventricular free wall were analyzed. Results: Left ventricular free wall LGE was detected in 56 out of 130 DCM patients. LGE was observed in both septal and free wall in 53 out of 56 patients with LGE (94.6%). Prevalence of NYHA classification Ⅲ/Ⅳ, intraventricular block, paroxysmal ventricular tachycardia, and secondary mitral insufficiency was significantly higher, while left ventricular ejection fraction was significantly lower, left ventricular end-diastolic/systolic volume, left ventricular end-diastolic/systolic volume index and left ventricular end-diastolic diameters values were larger in patients with LGE than without LGE (all P<0.05). In terms LGE pattern among these 56 patients, percent of involved myocardial segments in patients with subepicardial LGE (n=19) was significantly higher than patients with intermural LGE (n=30), patients with transmural LGE (n=21), and patients with subendocardial LGE (n=9)(60.8%(127/209) vs. 32.4%(107/330), 32.5%(75/231), 26.3%(26/99), respectively, all P < 0.01). Transmural LGE was most likely to involve the left ventricular inferior lateral basal (18/21) and mid (13/21) segment, followed by anterior lateral basal (15/21) and mid (11/21) segments and inferior mid segment (9/21). Subepicardial LGE was more likely to occur in the inferior lateral basal (13/19) and mid (16/19) segment, anterior lateral basal (13/19) and mid (15/19) segment, anterior lateral basal (13/19) and mid (15/19) segment, lateral apical (13/19), anterior and inferior mid segment (12/19 and 10/19), and apical segment (15/19 and 10/19). Intermural LGE mostly involved the anterior and inferior basal (19/30, 16/30) and mid (18/30 and 14/30) segment. There were 33 cases of single LGE pattern and 23 cases of multiple LGE pattern. Percent of involved myocardial segments was significantly higher in multiple LGE group than single LGE group (60.9% (154/253) vs. 49.9%(181/363), P = 0.007). Of 130 patients, 23 received heart transplantation, of which 6 patients had septal LGE alone and 17 patients had septal and free wall LGE. The rate of heart transplantation in the latter group was higher (32.1% (17/53)vs. 13.6%(6/44), P=0.034). Conclusions: There are several LGE distribution patterns in left ventricular wall among DCM patients.


Assuntos
Cardiomiopatia Dilatada , Meios de Contraste , Cardiomiopatia Dilatada/diagnóstico por imagem , Gadolínio , Humanos , Imagem Cinética por Ressonância Magnética , Valor Preditivo dos Testes , Estudos Retrospectivos , Volume Sistólico , Função Ventricular Esquerda
2.
Pol Merkur Lekarski ; 48(287): 335-338, 2020 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-33130794

RESUMO

Mitral valve prolapse (MVP) is diagnosed by auscultation and echocardiography in about 2-3% of the general population and takes rather a benign course. However, in some patients, ventricular arrhythmia and sudden cardiac death (SCD) occur, which is linked to mitral annular disjunction (MAD). MAD is defined as distinct separation of the mitral valve annulus-left atrial wall continuum and the basal region of the posterolateral left ventricular (LV) myocardium. MAD results in disturbed inferior-posterior LV wall and posteromedial papillary muscle stretch giving rise to local fibrosis presenting in cardiac magnetic resonance (CMR) as late gadolinium enhancement (LGE) and posing a substrate for malignant arrhythmia. Multidetector-row computed tomography (MDCT) in MAD patients is still rarely used. A CASE REPORT: Mitral valve prolapse (MVP) is diagnosed by auscultation and echocardiography in about 2-3% of the general population and takes rather a benign course. However, in some patients, ventricular arrhythmia and sudden cardiac death (SCD) occur, which is linked to mitral annular disjunction (MAD). MAD is defined as distinct separation of the mitral valve annulus-left atrial wall continuum and the basal region of the posterolateral left ventricular (LV) myocardium. MAD results in disturbed inferior-posterior LV wall and posteromedial papillary muscle stretch giving rise to local fibrosis presenting in cardiac magnetic resonance (CMR) as late gadolinium enhancement (LGE) and posing a substrate for malignant arrhythmia. Multidetector-row computed tomography (MDCT) in MAD patients is still rarely used.


Assuntos
Prolapso da Valva Mitral , Valva Mitral , Meios de Contraste , Gadolínio , Humanos , Valva Mitral/diagnóstico por imagem , Prolapso da Valva Mitral/diagnóstico por imagem , Músculos Papilares
3.
Medicine (Baltimore) ; 99(40): e22619, 2020 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-33019483

RESUMO

RATIONALE: Xanthogranuloma of the sellar region is exceedingly rare, and described in only a handful of case reports. Herein, we present a case of xanthogranuloma of the sellar region to improve our knowledge for the diagnosis and management of this unusual disease. PATIENT CONCERNS: A 50-year-old female presented with the symptoms of intermittent vomiting, occasional head discomfort, and diabetes insipidus of 1 month duration. DIAGNOSES: Magnetic resonance imaging showed a large well-defined, vase-like, heterogeneous mass in the sellar region. The lesion showed mixed signal with hierarchical signal presentation. Fluid-fluid level sign can be found within the lesion. The upper part of the lesion was hyperintense, and the lower part was hypointense on both T1-weighted images and T2-weighted images. The lesion showed no enhancement following the intravenous administration of gadolinium. The normal pituitary tissue was not clearly visible. Optic chiasm was compressed and displaced by the lesion. Initial diagnosis of pituitary macroadenoma with hemorrhage in the sellar region was made before surgery. Final diagnosis of sellar xanthogranuloma was confirmed by histopathological examination after surgical resection. INTERVENTIONS: Gross total resection of the lesion was achieved using the microscope through endonasal transsphenoidal approach. OUTCOMES: The patient recovered well with improved binocular vision and no symptom of diabetes insipidus, and was discharged 5 days after operation. LESSONS: Sellar xanthogranuloma should receive diagnostic consideration for the lesion that is a heterogeneously mixed mass with a degree of T1-weighted images hyperintense in the sellar region.


Assuntos
Diabetes Insípido/etiologia , Granuloma/cirurgia , Sela Túrcica/patologia , Xantomatose/patologia , Xantomatose/cirurgia , Diagnóstico Diferencial , Feminino , Gadolínio/administração & dosagem , Granuloma/patologia , Cefaleia/etiologia , Humanos , Imagem por Ressonância Magnética/métodos , Pessoa de Meia-Idade , Neoplasias Hipofisárias/diagnóstico , Sela Túrcica/diagnóstico por imagem , Resultado do Tratamento , Vômito/etiologia
4.
Zhonghua Xin Xue Guan Bing Za Zhi ; 48(9): 772-776, 2020 Sep 24.
Artigo em Chinês | MEDLINE | ID: mdl-32957761

RESUMO

Objective: To analysis the clinical characteristics and to summarize therapy experience of pediatric patients with cardiac syncope caused by anomalous origin of the left coronary artery from the right sinus (ALCA-R). Methods: We retrospectively analyzed the clinical data including clinical manifestations, myocardial injury biomarkers, radiological features, treatments and prognoses of pediatric patients with ALCA-R who were admitted to Beijing Children's Hospital from November 2015 to June 2018. Results: Four female patients were included in this analysis, age of onset was 7 to 14 years. All the patients presented with exercise-induced syncope and acute myocardial infarction. During the course, three patients presented with acute left heart failure, and one patient had history of sudden cardiac arrest. Laboratory data showed significant elevation of both the creatine kinase and troponin levels in four patients. All electrocardiogram (ECG) showed left main coronary artery occlusion, echocardiography suggested the possible anomalous origin of the left coronary artery in one child. Coronary CT angiography (CTA) revealed there was no coronary ostium in the left coronary sinus, and the left coronary artery had an anomalous origin from the right sinus. The left main coronary artery passed between the ascending artery and the root of the main pulmonary artery, which was compressed by these two large vessels. Two patients underwent cardiac magnetic resonance examination, which detected late gadolinium enhancement in ALCA-R with an interarterial course. Unroofing of the left coronary ostium (cut-back procedure) was performed in two patients, and the other two patients who were not operated were recommended to restrict their physical activities. During a regular follow-up period of 12-43 months, all the children survived without recurrent cardiovascular event. Conclusion: If an adolescent presents with exercise-induced syncope, acute myocardial infarction and even sudden death, and ECG shows left main coronary artery occlusion characteristics, we should consider the possibility of developmental abnormality of coronary artery, particularly the ALCA-R. Once diagnosed as ALCA-R, patients should be recommended to avoid strenuous activities,early recognition and surgical treatment are imperative for these patients.


Assuntos
Anomalias dos Vasos Coronários , Adolescente , Criança , Meios de Contraste , Angiografia Coronária , Feminino , Gadolínio , Humanos , Estudos Retrospectivos , Síncope
5.
J Biomed Nanotechnol ; 16(5): 594-602, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32919480

RESUMO

The current study aims to investigate the possibility of using solid lipid nanoparticles (SLNs)-enhanced magnetic resonance (MR) colonography to diagnose colorectal cancer. Gd-FITC-SLNs were synthesized by loading gadolinium diethylenetriaminepentaacetic acid (Gd-DTPA) and fluorescein isothiocyanate (FITC) simultaneously. Twenty mice received azoxymethane/dextran sulfate sodium (AOM/DSS) to induce adenocarcinoma of the colon and were divided into 4 groups, and 5 in per group. MR colonography were performed at different time periods before and after enema or intravenous injection of Gd-FITC-SLNs or Gd-DTPA. The results demonstrated SNR (signal-to-noise ratio) significantly increased from 1.56- to 1.76-fold within the colorectal tumors after the enema of Gd-FITC-SLNs (p < 0.001). No differences in SNR were observed after the enema of Gd-DTPA (p > 0.05). Besides, SNR increased from 1.54- to 1.72-fold within the colorectal tumors after the intravenous injection of Gd-FITC-SLNs (p < 0.001) while SNR increased from 1.39to 1.57-fold within the colorectal tumors after the injection of Gd-DTPA (p < 0.001). In addition, SNR within colorectal tumors significantly increased ranging from 20th to 140th min, and lasted for about 120 min (p < 0.05) after the enema of Gd-FITC-SLNs and SNR within colorectal tumors also significantly increased ranging from 0th hour to 8th hour, lasted for about 8 hour (p < 0.05) after the injection of Gd-FITC-SLNs. However, after the injection of Gd-DTPA, SNR within colorectal tumors significantly increased only ranging from 0th min to 20th min after administration (p < 0.01). Furthermore, hematoxylin and eosin (H&E) staining revealed that all mice developed adenocarcinoma of the colon. In summary, it is feasible by using Gd-FITC-SLNs in MR colonography to diagnose colorectal cancer. Enema of Gd-FITC-SLNs can provide marked enhancement of colorectal tumors quickly, and safer while intravenous injection of Gd-FITC-SLNs can provide a long-lasting enhancement of colorectal tumors in MR colonography. These findings present a potential clinical application of Gd-FITC-SLNs on MR colonography.


Assuntos
Neoplasias Colorretais , Nanopartículas , Animais , Neoplasias Colorretais/diagnóstico por imagem , Meios de Contraste , Gadolínio , Lipídeos , Imagem por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Camundongos
6.
Neurol Neurochir Pol ; 54(5): 399-409, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32955099

RESUMO

Gadolinium-based contrast agents (GBCAs) are widely used in magnetic resonance imaging (MRI) to help with the diagnostic and monitoring processes of many diseases, including neurological disorders. Initially, it was assumed that GBCAs carry minimal risk, are safe and well tolerated. But recent reports of GBCA-associated deposition in many body tissues have raised concerns about the broader health impacts of gadolinium exposure. The aim of this review was to summarise knowledge regarding gadolinium deposition, primarily in the brain structures, and of potential GBCA-associated toxicity. Moreover, we discuss the current recommendations on the use of GBCAs, as well as alternative contrast agents and imaging techniques.


Assuntos
Doenças do Sistema Nervoso , Encéfalo , Meios de Contraste/efeitos adversos , Gadolínio , Humanos , Imagem por Ressonância Magnética , Doenças do Sistema Nervoso/induzido quimicamente
7.
Radiol Med ; 125(11): 1114-1123, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32936388

RESUMO

Cardiovascular magnetic resonance has always been more often used in the last 10 years in evaluation of heart disease. Role in diagnosis of ischemia and in evaluation of myocardial infarction is well established by many scientific papers and included in current guidelines. High accuracy in evaluation of stress-induced ischemia, tissue characterization and functional parameters are the pillars the make the method widely used. In this paper are described role and techniques in diagnosis of ischemia, myocardial infarction and its sequelae.


Assuntos
Técnicas de Imagem Cardíaca/métodos , Imagem por Ressonância Magnética/métodos , Infarto do Miocárdio/diagnóstico por imagem , Meios de Contraste , Diagnóstico Diferencial , Gadolínio , Humanos , Microvasos/diagnóstico por imagem , Microvasos/lesões , Isquemia Miocárdica/diagnóstico por imagem
8.
Radiol Med ; 125(11): 1056-1071, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32946001

RESUMO

Cardiomyopathies are a heterogeneous entity. The progress in the field of genetics has allowed over the years to determine its origin more and more often. The classification of these pathologies has changed over the years; it has been updated with new knowledge. Imaging allows to define the phenotypic characteristics of the different forms of cardiomyopathy. Cardiac magnetic resonance (CMR) allows a morphological evaluation of the associated (and sometimes pathognomonic) cardiac findings of any form of cardiomyopathy. The tissue characterization sequences also make magnetic resonance imaging unique in its ability to detect changes in myocardial tissue. This review aims to define the features that can be highlighted by CMR in hypertrophic and dilated forms and the possible differential diagnoses. In hypertrophic forms, CMR provides: precise evaluation of wall thickness in all segments, ventricular function and size and evaluation of possible presence of areas of fibrosis as well as changes in myocardial tissue (measurement of T1 mapping and extracellular volume values). In dilated forms, cardiac resonance is the gold standard in the assessment of ventricular volumes. CMR highlights also the potential alterations of the myocardial tissue.


Assuntos
Técnicas de Imagem Cardíaca/métodos , Cardiomiopatia Dilatada/diagnóstico por imagem , Cardiomiopatia Hipertrófica/diagnóstico por imagem , Imagem por Ressonância Magnética/métodos , Adulto , Idoso , Cardiomiopatia Dilatada/genética , Cardiomiopatia Hipertrófica/genética , Meios de Contraste , Diagnóstico Diferencial , Feminino , Gadolínio , Septos Cardíacos/diagnóstico por imagem , Septos Cardíacos/patologia , Humanos , Hipertrofia/diagnóstico por imagem , Hipertrofia/patologia , Aumento da Imagem/métodos , Masculino , Pessoa de Meia-Idade
9.
Br J Radiol ; 93(1115): 20200514, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32795180

RESUMO

Takotsubo cardiomyopathy (TC) is a reversible condition in which there is transient left ventricular (LV) dysfunction characterised most commonly by basal hyperkinesis and mid-apical LV ballooning and hypokinesia. It is said to be triggered by stress and mimics, such as acute coronary syndrome (ACS) clinically. Diagnosis is usually suspected on echocardiography due to the characteristic contraction pattern in a patient with symptoms and signs of ACS but normal coronary arteries on catheter angiography. Cardiac magnetic resonance (CMR), with its latest advancements, is the diagnostic modality of choice for diagnosis, prognosis and follow-up of patients. The advances in CMR (including T1, T2, ECV mapping and threshold-based late gadolinium enhancement (LGE) measurements have revolutionised the role of CMR in tissue characterisation and prognostication in patients with TC. In this review, we highlight the current role of CMR in management of TC and enumerate the CMR findings in TC as well the current advances in the field of CMR, which could help in prognosticating these patients.


Assuntos
Algoritmos , Imagem por Ressonância Magnética/métodos , Cardiomiopatia de Takotsubo/diagnóstico por imagem , Circulação Coronária , Edema Cardíaco/diagnóstico por imagem , Fibrose/diagnóstico por imagem , Gadolínio , Humanos , Aumento da Imagem/métodos , Imagem por Ressonância Magnética/tendências , Imagem Cinética por Ressonância Magnética , Contração Miocárdica , Miocárdio/patologia , Cardiomiopatia de Takotsubo/etiologia , Cardiomiopatia de Takotsubo/fisiopatologia
10.
Radiología (Madr., Ed. impr.) ; 62(4): 327-329, jul.-ago. 2020. ilus
Artigo em Espanhol | IBECS | ID: ibc-194251

RESUMO

Varón de 57 años con antecedente de infarto de miocardio anterior. En una tomografía axial computarizada (TAC) cardíaca realizada 3 años más tarde, se objetiva una imagen hipodensa en el ápex del ventrículo izquierdo. Ante la sospecha de trombo, se completa el estudio mediante resonancia magnética cardíaca (RMC) con gadolinio, ecocardiografía transtorácica (ETT) 2D con ecopotenciador y ETT tridimensional. A través de la imagen multimodalidad se comprueba la ausencia de trombo


Cardiac computed tomography showed a hypodense area in the apex of the left ventricle in a 57-year-old man with a history of anterior myocardial infarction three years earlier. To confirm or rule out a suspected thrombus, he underwent gadolinium-enhanced cardiac magnetic resonance imaging, contrast-enhanced two-dimensional transthoracic echocardiography, and three-dimensional transthoracic echocardiography. Multimodality imaging ruled out the presence of a thrombus


Assuntos
Humanos , Masculino , Pessoa de Meia-Idade , Trombose/diagnóstico por imagem , Imagem Multimodal/métodos , Tomografia Computadorizada por Raios X/métodos , Cardiopatias/diagnóstico por imagem , Trombose/fisiopatologia , Processamento de Imagem Assistida por Computador , Gadolínio/administração & dosagem , Ecocardiografia/instrumentação
11.
Radiol Clin North Am ; 58(5): 841-850, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32792118

RESUMO

Moderate and severe contrast reactions are rare but can be life threatening. Appropriate contrast reaction management is necessary for the best patient outcome. This review summarizes the types and incidences of adverse events to contrast media, treatment algorithms, and equipment needed to treat common contrast reactions, the current status of contrast reaction management training, and preventative strategies to help mitigate adverse contrast events.


Assuntos
Meios de Contraste/efeitos adversos , Hipersensibilidade a Drogas/diagnóstico , Extravasamento de Materiais Terapêuticos e Diagnósticos/prevenção & controle , Gadolínio/efeitos adversos , Iodo/efeitos adversos , Radiologia/educação , Humanos , Erros de Medicação/prevenção & controle , Fatores de Risco
12.
Am J Cardiol ; 131: 104-108, 2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32718552

RESUMO

Hypertrophic cardiomyopathy (HC) represents a major cause of sudden cardiac death in young adults. Late gadolinium enhancement (LGE) and extracellular volume (ECV) by T1 mapping are cardiac magnetic resonance (CMR) techniques to quantify fibrosis in HC. The relationships of LGE and ECV with ventricular arrhythmia, left ventricular (LV) diastolic function, and risk factors for sudden cardiac death (SCD) in HC are unclear. We studied 103 HC patients (mean age 51 ± 14, 42% women) who underwent CMR from 2012 to 2014. Global LGE and mean ECV were evaluated in relation to history of nonsustained ventricular tachycardia (NSVT), diastolic function by echocardiography, and SCD risk factors. LGE was present in 71 (69%) subjects. Wide variation was demonstrated in LGE (0.5% to 45.9%) and mean ECV (17.6% to 47.4%). Prevalence of NSVT increased continuously with LGE and was greater in subjects with ECV above the study population mean (27%). Increased LGE was associated with LV diastolic dysfunction and LV wall thickness. In conclusion, while ECV appears to have a threshold (27%) above which it is associated with NSVT, LGE demonstrates a more robust relationship with NSVT and measures of diastolic dysfunction.


Assuntos
Cardiomiopatia Hipertrófica/diagnóstico por imagem , Cardiomiopatia Hipertrófica/fisiopatologia , Imagem Cinética por Ressonância Magnética , Taquicardia Ventricular/diagnóstico por imagem , Taquicardia Ventricular/fisiopatologia , Adolescente , Adulto , Idoso , Meios de Contraste , Ecocardiografia , Feminino , Gadolínio , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco
13.
Korean J Radiol ; 21(8): 978-986, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32677382

RESUMO

OBJECTIVE: To compare native and post-contrast T1 mapping with late gadolinium enhancement (LGE) imaging for detecting and measuring the microvascular obstruction (MVO) area in reperfused acute myocardial infarction (MI). MATERIALS AND METHODS: This study included 20 patients with acute MI who had undergone 1.5T cardiovascular magnetic resonance imaging (CMR) after reperfusion therapy. CMR included cine imaging, LGE, and T1 mapping (modified look-locker inversion recovery). MI size was calculated from LGE by full-width at half-maximum technique. MVO was defined as an area with low signal intensity (LGE) or as a region of visually distinguishable T1 values (T1 maps) within infarcted myocardium. Regional T1 values were measured in MVO, infarcted, and remote myocardium on T1 maps. MVO area was measured on and compared among LGE, native, and post-contrast T1 maps. RESULTS: The mean MI size was 27.1 ± 9.7% of the left ventricular mass. Of the 20 identified MVOs, 18 (90%) were detected on native T1 maps, while 10 (50%) were recognized on post-contrast T1 maps. The mean native T1 values of MVO, infarcted, and remote myocardium were 1013.5 ± 58.5, 1240.9 ± 55.8 (p < 0.001), and 1062.2 ± 55.8 ms (p = 0.169), respectively, while the mean post-contrast T1 values were 466.7 ± 26.8, 399.1 ± 21.3, and 585.2 ± 21.3 ms, respectively (p < 0.001). The mean MVO areas on LGE, native, and post-contrast T1 maps were 134.1 ± 81.2, 133.7 ± 80.4, and 117.1 ± 53.3 mm², respectively. The median (interquartile range) MVO areas on LGE, native, and post-contrast T1 maps were 128.0 (58.1-215.4), 110.5 (67.7-227.9), and 143.0 (76.7-155.3) mm², respectively (p = 0.002). Concordance correlation coefficients for the MVO area between LGE and native T1 maps, LGE and post-contrast T1 maps, and native and post-contrast T1 maps were 0.770, 0.375, and 0.565, respectively. CONCLUSION: MVO areas were accurately delineated on native T1 maps and showed high concordance with the areas measured on LGE. However, post-contrast T1 maps had low detection rates and underestimated MVO areas. Collectively, native T1 mapping is a useful tool for detecting MVO within the infarcted myocardium.


Assuntos
Coração/diagnóstico por imagem , Imagem Cinética por Ressonância Magnética/métodos , Infarto do Miocárdio/diagnóstico por imagem , Infarto do Miocárdio/patologia , Traumatismo por Reperfusão Miocárdica/diagnóstico por imagem , Adulto , Meios de Contraste , Feminino , Gadolínio , Humanos , Aumento da Imagem , Masculino , Pessoa de Meia-Idade , Traumatismo por Reperfusão Miocárdica/patologia , Miocárdio/patologia
14.
Chemosphere ; 257: 127250, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32600781

RESUMO

Widespread use of gadolinium-based contrast agents in medical imaging has resulted in increased Gd inputs to municipal wastewater treatment plants. Others have reported that typical wastewater treatment does not attenuate Gd, resulting in discharges to natural waters. However, whether elevated Gd impacts the performance of biological treatment has not been investigated. We examined whether gadolinium chloride or Gd chelated with diethylenetriaminepentaacetic acid (DTPA) affected the activity of the model nitrifying bacterium Nitrosomonas europaea. At nominal GdCl3 additions ranging from 1 to 500 µM, no impact was observed compared to the control. Most (>98%) of the added Gd precipitated, and extracellular GdPO4 nanoparticles were observed. When chelated with DTPA, Gd remained soluble, but no statistically significant impact on ammonia oxidation was observed until the highest concentrations tested. At 300 and 500 µM Gd-DTPA, a temporary reduction of nitrite production relative to the control (effect size 1.3 mg l-1 and 1.5 mg l-1, respectively, at 24 h) was seen. By itself, DTPA was highly inhibitory. Modeling suggested that DTPA likely chelated other metals, but adjusting the concentrations of the most abundant metals in the medium, calcium and magnesium, indicated that lowering their free ion activities was probably not the cause of inhibition. Complexation of other essential metals was more likely. Our studies indicate that while the low bioavailability of Gd may limit its ecosystem impacts, the role of synthetic ligands used with Gd and other rare earth elements should be considered as the production, use and disposal of these elements increases.


Assuntos
Amônia/metabolismo , Gadolínio/toxicidade , Nitrosomonas europaea/metabolismo , Poluentes Químicos da Água/metabolismo , Ecossistema , Gadolínio DTPA , Metais Terras Raras , Nitritos , Nitrosomonas , Oxirredução , Águas Residuárias
15.
Am Heart J ; 226: 206-213, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32615358

RESUMO

INTRODUCTION: Endurance athletes are at higher risk for developing atrial fibrillation as compared to the general population. The exact mechanism to explain this observation is incompletely understood. Our study aimed to determine whether degree of left atrial fibrosis detected by late gadolinium-enhancement magnetic resonance imaging (LGE-MRI) differed between Masters athletes and non-athlete controls. METHODS: We recruited 20 endurance healthy Masters athletes and 20 healthy control subjects who underwent cardiac MRI. Healthy controls were recruited during screening colonoscopies and Masters athletes were recruited through word of mouth and at competitions. The two groups were age and gender matched. None of the participants were known to have an arrhythmia. Fibrosis, as measured by late gadolinium-enhancement, was measured in each participant by blinded readers. The degree of left atrial fibrosis was compared between the two groups. All participants were recruited from the Salt Lake City region and scanned at the University of Utah healthcare complex. RESULTS: Left ventricular function was normal in all study participants. Left atrial volumes were significantly larger in the athletes (74.2 ml ±â€¯14.4) as compared to the healthy control subjects (60.8 mL ±â€¯21.4) (P = .02). Mean left atrial fibrosis score, reported as a percentage of the LA, was 15.5% ±â€¯5.9 in the athlete cohort compared to 9.6% ±â€¯4.9 in the controls (P = .002). CONCLUSIONS: To our knowledge this is the first study that describes, characterizes and specifically quantifies fibrotic changes within the left atrium of highly trained endurance athletes. Increased atrial fibrosis seen in this population may be an early indicator for endurance athletes at risk of developing atrial arrhythmias.


Assuntos
Treino Aeróbico/efeitos adversos , Átrios do Coração/diagnóstico por imagem , Átrios do Coração/patologia , Imagem por Ressonância Magnética , Adulto , Estudos de Coortes , Meios de Contraste , Treino Aeróbico/métodos , Feminino , Fibrose/diagnóstico por imagem , Fibrose/etiologia , Gadolínio , Humanos , Imagem por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Esportes
16.
Int J Nanomedicine ; 15: 4691-4703, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32636625

RESUMO

Purpose: Gd-encapsulated carbonaceous dots (Gd@C-dots) have excellent stability and magnetic properties without free Gd leakage, therefore they can be considered as a safe alternative T1 contrast agent to commonly used Gd complexes. To improve their potential for cancer diagnosis and treatment, affibody-modified Gd@C-dots targeting non-small-cell lung cancer (NSCLC) EGFR-positive tumors with enhanced renal clearance were developed and synthesized. Materials and Methods: Gd@C-dots were developed and modified with Ac-Cys-ZEGFR:1907 through EDC/NHS. The size, morphology, and optical properties of the Gd@C-dots and Gd@C-dots-Cys-ZEGFR:1907 were characterized. Targeting ability was evaluated by in vitro and in vivo experiments, respectively. Residual gadolinium concentration in major organs was detected with confocal imaging and inductively coupled plasma mass spectrometry (ICP-MS) ex vivo. H&E staining was used to assess the morphology of these organs. Results: Gd@C-dots with nearly 20 nm in diameter were developed and modified with Ac-Cys-ZEGFR:1907. EGFR expression in HCC827 cells was higher than NCI-H520. In cell uptake assays, EGFR-expressing HCC827 cells exhibited significant MR T1WI signal enhancement when compared to NCI-H520 cells. Cellular uptake of Gd@C-dots-Cys-ZEGFR:1907 was reduced, when Ac-Cys-ZEGFR:1907 was added. In vivo targeting experiments showed that the probe signal was significantly higher in HCC827 than NCI-H520 xenografts at 1 h after injection. In contrast to Gd@C-dots, Gd@C-dots-Cys-ZEGFR:1907 nanoparticles can be efficiently excreted through renal clearance. No morphological changes were observed by H&E staining in the major organs after injection of Gd@C-dots-Cys-ZEGFR:1907. Conclusion: Gd@C-dots-Cys-ZEGFR:1907 is a high-affinity EGFR-targeting probe with efficient renal clearance and is therefore a promising contrast agent for clinical applications such as diagnosis and treatment of NSCLC EGFR-positive malignant tumors.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Meios de Contraste/farmacocinética , Neoplasias Pulmonares/diagnóstico por imagem , Imagem por Ressonância Magnética/métodos , Pontos Quânticos/química , Animais , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Meios de Contraste/química , Receptores ErbB/metabolismo , Feminino , Gadolínio/química , Gadolínio/farmacocinética , Humanos , Rim/efeitos dos fármacos , Rim/metabolismo , Neoplasias Pulmonares/patologia , Camundongos Nus , Nanopartículas/química , Distribuição Tecidual , Ensaios Antitumorais Modelo de Xenoenxerto
19.
Phys Med Biol ; 65(19): 195005, 2020 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-32575086

RESUMO

Gadolinium aluminum gallium garnet (GAGG) is a promising scintillator crystal for positron emission tomography (PET) detectors owing to its advantages of energy resolution, light yield, and absence of intrinsic radiation. However, a large portion of the incident photons undergoes Compton scattering within GAGG crystal because of its low stopping power compared to that of lutetium-based crystals such as Lu2SiO5 (LSO). Inter-detector scattering (IDS) and inter-crystal scattering (ICS) result in loss of sensitivity and image quality of PET, respectively. We performed a Monte Carlo simulation study to evaluate IDS recovery in our currently developing brain-dedicated PET, and extended the idea to ICS recovery. We also compared the impact of the recoveries on LSO- and GAGG-based PET scanners. We measured the sensitivity and spatial resolution of the brain PET, and analyzed the image quality using a lesion phantom, a hot-rod phantom, and a 2D Hoffman phantom with applying IDS or ICS recovery. IDS recovery increased the PET sensitivity and improved the noise level of the reconstructed images. ICS recovery enhanced the spatial resolution and the contrast of the images was improved. As the occurrence rates of IDS and ICS were higher in GAGG than in LSO, the overall impact of IDS or ICS recovery was significant in GAGG. In conclusion, we showed that the proportional method would be suitable for IDS and ICS recoveries of PET, and emphasized the importance of ICS and IDS recoveries for PET using crystals with low stopping power.


Assuntos
Encéfalo/diagnóstico por imagem , Gadolínio/química , Gálio/química , Lutécio/química , Imagens de Fantasmas , Tomografia por Emissão de Pósitrons/métodos , Compostos de Silício/química , Desenho de Equipamento , Humanos , Processamento de Imagem Assistida por Computador/métodos , Método de Monte Carlo , Fótons , Contagem de Cintilação/instrumentação
20.
Pediatr Cardiol ; 41(6): 1173-1179, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32476037

RESUMO

Cardiomyopathy is the leading cause of death in Duchenne muscular dystrophy (DMD). Elevated troponin levels are observed in DMD and may vary with disease progression. We studied troponin levels in DMD related to cardiac fibrosis and native T1 measures. This is a prospective, cross-sectional, observational study of 30 DMD subjects measuring native T1 levels and late gadolinium enhancement (LGE) on cardiac MR imaging (CMR) correlated with temporally associated serum troponin I levels. Non-parametric analyses including Spearman correlations and Kruskal-Wallis test were performed between groups. p values resulting from the pair-wise comparisons were adjusted for multiple comparisons using the Sidak method where appropriate. There were 15 DMD subjects with no LGE (age 12 ± 3 yo; EF% 60 ± 5) and troponin I level of 0.05 ± 0.08 ng/ml, of which three had an abnormal troponin level (over 0.04 ng/ml); 7 DMD subjects with mild LGE (age 17 ± 5 yo, EF% 52 ± 8) and troponin I level of 0.28 ± 0.36 ng/ml, of which five had an abnormal troponin level; and 8 DMD subjects with moderate-to-severe LGE (age 16 ± 6 yo; EF% 54 ± 8) and troponin I level of 0.11 ± 0.14 ng/ml, of which four had an abnormal troponin level. Troponin I levels in DMD subjects with mild LGE was significantly increased compared to subjects with no LGE (p = 0.02). There was a statistically significant positive correlation between troponin I levels and MOLLI septal native T1 values (r2 = 0.173, p = 0.02). Overall, MOLLI lateral native T1 levels were increased with moderate-severe LGE compared to mild and none (p < 0.01). Serum biomarker troponin I levels were increased in DMD subjects with mild LGE and correlated with MOLLI septal native T1 values. Troponin I levels may be a useful minimally invasive outcome marker to monitor myocardial disease progression in DMD cardiomyopathy.


Assuntos
Cardiomiopatias/diagnóstico por imagem , Imagem por Ressonância Magnética/métodos , Distrofia Muscular de Duchenne/complicações , Troponina I/sangue , Adolescente , Biomarcadores/sangue , Cardiomiopatias/etiologia , Criança , Meios de Contraste/administração & dosagem , Estudos Transversais , Progressão da Doença , Feminino , Gadolínio/administração & dosagem , Humanos , Masculino , Estudos Prospectivos , Adulto Jovem
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