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1.
Nihon Hoshasen Gijutsu Gakkai Zasshi ; 75(12): 1411-1419, 2019.
Artigo em Japonês | MEDLINE | ID: mdl-31866639

RESUMO

We determined the procedure to reduce arrhythmia-related ghosting artifacts in the late gadolinium enhancement (LGE) imaging of cardiovascular magnetic resonance (CMR) in patients with arrhythmia by examining the causing factors using phantoms. Inversion recovery gradient echo and phase-sensitive inversion recovery (PSIR) sequences were compared under normal sinus rhythm and premature ventricular contraction (PVC) conditions. Under the PVC condition, trigger interval irregularly performed induced ghosting artifacts. A phase-corrected real image in PSIR, however; demonstrated an accurately positive contrast of pale LGE area indicative of mild fibrosis with minimal ghosting artifacts. The study results indicate that PSIR has an advantage for LGE CMR in patients with arrhythmia. Even without having PSIR method, the 2R-R method ensures consistency of contrast and enables reduction of ghost artifacts.


Assuntos
Imagem por Ressonância Magnética , Meios de Contraste , Gadolínio , Humanos , Espectroscopia de Ressonância Magnética , Miocárdio
2.
Medicine (Baltimore) ; 98(44): e17807, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31689864

RESUMO

To explore a comparable method to Gd-contrast enhancement in the preoperative evaluation of anal fistula to evaluate its morphology changes.Forty-six patients with anal fistula were enrolled. Each patient acquired a 3.0T magnetic resonance imaging (MRI) routine sequence, diffusion-weighted imaging (DWI) sequence and fat suppression T1 weighted imaging (FS T1WI) contrast enhancement (CE) scanning. To record the morphology performances of the internal orifice and the fistulas on the transverse images of fat suppression T2 weighted imaging (FS T2WI), DWI, FS T2WI combined with DWI, FS T1WI Gd-CE, with the standard of the surgical pathology results. Two observers evaluated images in consensus. The conspicuity and the diagnostic performance rate were compared between the 4 imaging data sets.The consistencies of interobservers about the conspicuity scores and the diagnostic performance rates of the internal orifice and the fistula were good. The conspicuity of the internal orifice was higher for the set of FS T2WI, FS T2WI+DWI, and FS T1WI+CE than DWI. The diagnostic performance rate of the internal orifice was higher for the set of FS T2WI, FS T2WI+DWI, and FS T1WI+CE than DWI. The conspicuity of the fistula was higher for the set of FS T2WI+DWI and FS T1WI+CE than FS T2WI or DWI. There were no significantly differences between the 4 sets of FS T2WI, DWI, FS T2WI+DWI, and FS T1WI+CE in the diagnostic performance rate of the fistula.The set of FS T2WI combined with DWI was comparable to FS T1WI CE in evaluation of anal fistula morphology changes.


Assuntos
Meios de Contraste , Imagem de Difusão por Ressonância Magnética/métodos , Gadolínio , Fístula Retal/diagnóstico por imagem , Fístula Retal/patologia , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Cuidados Pré-Operatórios , Adulto Jovem
3.
Int J Nanomedicine ; 14: 7879-7889, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31576129

RESUMO

Introduction and objective: Precisely and sensitively diagnosing diseases especially early and accurate tumor diagnosis in clinical magnetic resonance (MR) scanner is a highly demanding but challenging task. Gadolinium (Gd) chelate is the most common T 1 magnetic resonance imaging (MRI) contrast agent at present. However, traditional Gd-chelates are suffering from low relaxivity, which hampers its application in clinical diagnosis. Currently, the development of nano-sized Gd based T 1 contrast agent, such as incorporating gadolinium chelate into nanocarriers, is an attractive and feasible strategy to enhance the T 1 contrast capacity of Gd chelate. The objective of this study is to improve the T 1 contrast ability of Gd-chelate by synthesizing nanoparticles (NPs) for accurate and early diagnosis in clinical diseases. Methods: Reverse microemulsion method was used to coat iron oxide (IO) with tunable silica shell and form cores of NPs IO@SiO2 at step one, then Gd-chelate was loaded on the surface of silica-coated iron oxide NPs. Finally, Gd-based silica coating magnetite NPs IO@SiO2-DTPA-Gd was developed and tested the ability to detect tumor cells on the cellular and in vivo level. Results: The r 1 value of IO@SiO2-DTPA-Gd NPs with the silica shell thickness of 12 nm was about 33.6 mM-1s-1, which was approximately 6 times higher than Gd-DTPA, and based on its high T 1 contrast ability, IO@SiO2-DTPA-Gd NPs could effectively detect tumor cells on the cellular and in vivo level. Conclusion: Our findings revealed the improvement of T 1 relaxation was not only because of the increase of molecular tumbling time caused by the IO@SiO2 nanocarrier but also the generated magnetic field caused by the IO core. This nanostructure with high T 1 contrast ability may open a new approach to construct high-performance T 1 contrast agent.


Assuntos
Quelantes/química , Materiais Revestidos Biocompatíveis/química , Gadolínio/química , Imagem por Ressonância Magnética , Nanopartículas de Magnetita/química , Dióxido de Silício/química , Animais , Morte Celular , Meios de Contraste/química , Feminino , Compostos Férricos/química , Gadolínio DTPA/química , Células HeLa , Humanos , Nanopartículas de Magnetita/ultraestrutura , Camundongos Endogâmicos BALB C , Camundongos Nus , Imagem Molecular
4.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 50(4): 483-488, 2019 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-31642223

RESUMO

OBJECTIVE: To study the application value of motion-correction phase sensitive inversion recovery (MOCO-PSIR) to evaluate myocardial fibrosis in the patients with heart failure caused by dilated cardiomyopathy (DCM). METHODS: A prospective study included 60 patients who underwent cardiac MRI enhanced scan from June 2017 to November 2018, including 38 patients who were clinically diagnosed with DCM and 22 patients in the normal control group. All patients were scanned with three late gadolinium enhancement (LGE) sequences: segmented-PSIR, single-shot-PSIR, MOCO-PSIR at the same time. The subjective quality score (level 4) and image signal-to-noise ratio (objective evaluation) of normal and abnormal myocardium were analyzed and compared in three scanning technique groups. The detection rate of myocardial fibrosis and image acquisition time of the three scanning techniques were recorded. RESULTS: In the normal control group (sinus rhythm), subjective score showed no statistical significance. Subjective scoring results in the patients with DCM: MOCO-PSIR>single-shot-PSIR> segmented-PSIR (P < 0.05). SNR results PSIR-LGE images in DCM patients as well as control group: segmented-PSIR>MOCO-PSIR> single-shot-PSIR (P < 0.05). In the whole 646 segments analysis of DCM patients, the ratio unable to judge in segmented-PSIR was up to 25.5%, but only 1.4% in MOCO-PSIR. Significant difference was found in the three groups. While in the 374 segments of control group, no statistical difference was found in comparison of incapability to judge. Acquisition time covered left ventricular: (5.6±1.7) min in segmented-PSIR, (0.4±0.2) min in single-shot-PSIR and (4.5±1.1) min in MOCO-PSIR. Pairwise comparison of acquisition time among three scanning techniques was statistically significant (P < 0.001). CONCLUSION: MOCO-PSIR-LGE has better clinical significance than conventional delayed enhanced scan sequences in the diagnosis of myocardial fibrosis in the patients with heart failure caused by dilated cardiomyopathy.


Assuntos
Cardiomiopatia Dilatada/diagnóstico por imagem , Insuficiência Cardíaca/diagnóstico por imagem , Imagem por Ressonância Magnética , Miocárdio/patologia , Estudos de Casos e Controles , Meios de Contraste , Fibrose , Gadolínio , Humanos , Aumento da Imagem , Estudos Prospectivos
5.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 50(4): 489-493, 2019 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-31642224

RESUMO

OBJECTIVE: To determine segmental myocardial changes in cardiovascular magnetic resonance feature-tracking (CMR-FT) in the early phase of reperfused myocardial infarction in patients and rats. METHODS: Ten patients receiving percutaneous coronary interventions (2-10 d) and 10 rats with 60 min induced myocardial ischemia followed by reperfusions (48 h and 7 d) were investigated by MRI. The steady state free precession cine and late gadolinium enhancement (LGE) sequences were measured to evaluate the standard short axis of the whole heart after an injection of gadolinium diethylenetriamine pentaacetic acid (Gd-DTPA, Magnevist, Bayer Health Care Pharmaceuticals) at a dose of 0.1 mmol/kg. The infarction sizes (all areas were expressed as a percentage of the whole myocardial tissues of left ventricle (LV), end-diastolic volume (EDV) and ejection fractions (EF) were calculated. The MRI cine images were analyzed using the myocardial feature tracking software CVI, estimating the peak value of radial strains (RS) and circumferential strains (CS) of the 16 AHA segments excluding apex cordis. The complete myocardial infarction (CMI) segments, partial myocardial infarction (PMI) segments and non-myocardial infarction (NMI) segments were identified and compared. RESULTS: Patients: The radial strain and circumferential strain of the CMI and PMI segments were smaller than the NMI segment (both P < 0.01). However, there was no significant difference between the CMI and the PMI segment (P>0.05). Rats: No significance differences were found in EF and EDV between the two time period 48 h and 7 d (both P>0.05). The radial strain and circumferential strain of the CMI and PMI segments were smaller than the NMI segment (all P < 0.01). But there was no significance difference between the CMI segment and the PMI segment (P>0.05). No significant changes in the global radial strain and the circumferential strain were found over time (both P>0.05). But the segmental radial strain and circumferential strain became larger over time (all P < 0.05). CONCLUSIONS: The systolic ability of myocardium decreases as a result of reperfusion injury in the early phase of reperfused myocardial infarction. But it can gradually recover over time with reperfusion.


Assuntos
Imagem Cinética por Ressonância Magnética , Infarto do Miocárdio/diagnóstico por imagem , Animais , Meios de Contraste , Gadolínio , Gadolínio DTPA , Humanos , Ratos
6.
J Assoc Physicians India ; 67(8): 35-38, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31562714

RESUMO

Objective: Cardiac amyloidosis (CA) is not well recognized in Indian literature. The aim of this communication is to highlight the difficulties in diagnosis. Methods: A retrospective analysis of data of six patients of CA diagnosed during 2008 to 2015 was done. Clinical, investigative, management and follow-up data is analyzed. Results: The mean age was 51 years with male preponderance. Heart failure was the commonest manifestation. Atrial arrhythmias were seen in 33%. Syncope, peripheral neuropathy and macroglossia were striking features. A speckled inter-ventricular septum (66%) or thickened inter-atrial septum (16%) on echocardiography strongly favoured CA. Other echocardiography features include thickened ventricular wall, enlarged atria and pericardial effusion (PE). Late gadolinium enhancement (LGE) on cardiac magnetic resonance (CMR) was characteristic of CA. Plasma cell dyscrasia confirmed light chain amyloidosis. Abdominal fat pad and rectal biopsy confirmed the diagnosis. Chemotherapy for plasma cell dyscrasia was administered in 50% of patients. Conclusion: Echocardiography and CMR imaging enable the diagnosis of CA in background of strong clinical suspicion. Abdominal fat pad biopsy is a simple and reliable method for confirming the diagnosis. Implications and Practice: The awareness of this entity can enable an early diagnosis and improve the survival with timely novel chemotherapy.


Assuntos
Amiloidose , Cardiomiopatias , Meios de Contraste , Gadolínio , Humanos , Índia , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Miocárdio , Valor Preditivo dos Testes , Estudos Retrospectivos
7.
Chem Commun (Camb) ; 55(79): 11924-11927, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31528965

RESUMO

We report a novel ditopic Gd(iii)-based probe selective to zwitterionic amino acid neurotransmitters (ZNTs) crafted for ratiometric MRI imaging. The probe displayed increased binding affinity to ZNTs and non-synchronized concentration-dependent changes of the r1- and r2-relaxivity. Through the application of a T2/T1 weighted MRI strategy, we demonstrated signal enhancement for cooperatively bound glutamate and γ-aminobutyric acid ZNTs over competitive hydrogencarbonate, which remained MR silent.


Assuntos
Aminoácidos/química , Meios de Contraste/química , Complexos de Coordenação/química , Gadolínio/química , Imagem por Ressonância Magnética/métodos , Neurotransmissores/análise , Bicarbonatos/análise , Técnicas Biossensoriais/métodos , Ácido Glutâmico/análise , Ligantes , Compostos Macrocíclicos/química , Peso Molecular , Ácido gama-Aminobutírico/análise
8.
Br J Radiol ; 92(1104): 20190513, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31529977

RESUMO

MRI is an invaluable diagnostic tool in the investigation and management of patients with pathology of the head and neck. However, numerous technical challenges exist, owing to a combination of fine anatomical detail, complex geometry (that is subject to frequent motion) and susceptibility effects from both endogenous structures and exogenous implants. Over recent years, there have been rapid developments in several aspects of head and neck imaging including higher resolution, isotropic 3D sequences, diffusion-weighted and diffusion-tensor imaging as well as permeability and perfusion imaging. These have led to improvements in anatomic, dynamic and functional imaging. Further developments using contrast-enhanced 3D FLAIR for the delineation of endolymphatic structures and black bone imaging for osseous structures are opening new diagnostic avenues. Furthermore, technical advances in compressed sensing and metal artefact reduction have the capacity to improve imaging speed and quality, respectively. This review explores novel and evolving MRI sequences that can be employed to evaluate diseases of the head and neck, including the skull base.


Assuntos
Neoplasias dos Nervos Cranianos/diagnóstico por imagem , Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Imagem por Ressonância Magnética/métodos , Neoplasias da Base do Crânio/diagnóstico por imagem , Artefatos , Osso e Ossos/diagnóstico por imagem , Tecido Conjuntivo/diagnóstico por imagem , Meios de Contraste , Imagem de Difusão por Ressonância Magnética , Hidropisia Endolinfática/diagnóstico por imagem , Gadolínio , Perda Auditiva Neurossensorial/diagnóstico por imagem , Perda Auditiva Súbita/diagnóstico por imagem , Humanos , Angiografia por Ressonância Magnética , Imagem por Ressonância Magnética/tendências
10.
Pol Merkur Lekarski ; 47(277): 19-24, 2019 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-31385942

RESUMO

Legionella pneumophila infection (legionellosis) usually presents as a multisystemic disease, predominantly affecting the lungs (Legionnaires' disease - LD). Immunodeficiency, chemotherapy or chronic steroids use increase the risk of developing LD. Extrapulmonary manifestations of LD include cardiac complications: myocarditis, pericarditis or endocarditis. A CASE REPORT: The authors describe a case of a 51-year-old female with a history of cryoglobulinemic vasculitis, Sjögren syndrome and chronic lymphocytic leukemia who was admitted due to a high fever, fatigue, tachycardia, dyspnea and cough. Chest X-ray and CT showed bilateral pulmonary infiltrations and pleural effusion. LD was diagnosed on positive L. pneumophila urinary antigen test. Echocardiography revealed severe left ventricular (LV) dysfunction with substantially decreased ejection fraction and global longitudinal strain (GLS), with a pattern resembling reverse takotsubo syndrome (rTTS). The coronary arteries in non-invasive coronary angiography were normal. During therapy with levofloxacin and intravenous immunoglobulins as well as with carvedilol, ramipril and diuretics, gradual clinical improvement with complete normalization of LV function was observed within 5 weeks. Cardiac magnetic resonance (CMR) performed on day 35 revealed only small intramural foci of late gadolinium enhancement (LGE) with localization not corresponding to the most decreased regional longitudinal strain in the initial echocardiographic examination. The authors suggest that the mechanism of transient LV dysfunction in the case presented may have been of complex nature, including LD myocarditis and stress-induced cardiomyopathy (with the prevalence of the latter) which has not so far been reported in the literature.


Assuntos
Legionella pneumophila , Legionella , Doença dos Legionários , Pneumonia , Disfunção Ventricular Esquerda , Meios de Contraste , Feminino , Gadolínio , Humanos , Doença dos Legionários/complicações , Pessoa de Meia-Idade , Pneumonia/complicações , Disfunção Ventricular Esquerda/etiologia
11.
Sci Total Environ ; 687: 1401-1408, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31412473

RESUMO

Gadolinium-based contrast agents used in magnetic resonance imaging are difficult to impossible to remove in wastewater treatment plants, and may enter groundwater production wells and hence municipal tap water via bank filtration. As anthropogenic gadolinium (Gd) may be accompanied by other, more harmful waste water-derived (micro)pollutants such as endocrine disruptors, we investigated the potential pathway of anthropogenic Gd into popular tap water-based beverages sold in highly frequented fast food restaurants. We, therefore, determined the concentration and distribution of geogenic and anthropogenic rare earth elements (REE) in tap water and in a related tap water-based popular soft drink (Coca Cola) from two fast food franchises (McDonalds and Burger King) in six major German cities. We observed anthropogenic Gd in both tap water and corresponding soft drinks in all investigated cities, extending the database for anthropogenic Gd in tap waters and highlighting its widespread distribution. In Berlin and Düsseldorf, where tap water is (mainly) produced by river bank filtration, 85 to 99% of the total Gd is of anthropogenic origin. The surprisingly high anthropogenic fraction (91%) in tap water from Munich reveals that even the shallow groundwater tapped in two Alpine valleys is eventually exposed to anthropogenic pollution. The REE distribution in post-mix soft drinks generally follows that of the corresponding tap water, except for enrichments of ytterbium (Yb), lutetium (Lu) and cerium (Ce), which are derived from the syrup. The concentration of anthropogenic Gd is similar in the soft drinks and in the corresponding tap water, demonstrating that the highly stable Gd-based contrast agents are not removed in soda fountains but are directly transferred to the beverages. This study highlights a pathway for anthropogenic waste water-derived xenobiotics such as pharmaceuticals and endocrine disruptors into the food chain, and hence, reveals the potential for human exposure to potentially harmful anthropogenic compounds.


Assuntos
Monitoramento Ambiental , Gadolínio/análise , Restaurantes , Poluentes Químicos da Água/análise , Cidades , Fast Foods , Alemanha
13.
Br J Radiol ; 92(1103): 20190443, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31433668

RESUMO

MRI of articular cartilage (AC) integrity has potential to become a biomarker for osteoarthritis progression. Traditional MRI sequences evaluate AC morphology, allowing for the measurement of thickness and its change over time. In the last two decades, more advanced, dedicated MRI cartilage sequences have been developed aiming to assess AC matrix composition non-invasively and detect early changes in cartilage not captured on morphological sequences. T2-mapping and T1ρ sequences can be used to estimate the relaxation times of water inside the AC. These sequences have been introduced into clinical protocols and show promising results for cartilage assessment. Extracelullar matrix can also be assessed using diffusion-weighted imaging and diffusion tensor imaging as the movement of water is limited by the presence of extracellular matrix in AC. Specific techniques for glycosaminoglycans (GAG) evaluation, such as delayed gadolinium enhanced MRI of cartilage or Chemical Exchange Saturation Transfer imaging of GAG, as well as sodium imaging have also shown utility in the detection of AC damage. This manuscript provides an educational update on the physical principles behind advanced AC MRI techniques as well as a comprehensive review of the strengths and weaknesses of each approach. Current clinical applications and potential future applications of these techniques are also discussed.


Assuntos
Cartilagem Articular/fisiologia , Matriz Extracelular/fisiologia , Imagem por Ressonância Magnética/métodos , Meios de Contraste , Gadolínio , Glicosaminoglicanos/metabolismo , Humanos , Imagem por Ressonância Magnética/normas , Prognóstico , Sensibilidade e Especificidade , Sódio
14.
Zhonghua Xin Xue Guan Bing Za Zhi ; 47(8): 622-627, 2019 Aug 24.
Artigo em Chinês | MEDLINE | ID: mdl-31434433

RESUMO

Objective: To investigate the cardiovascular magnetic resonance (CMR) imaging characteristics and influence factors of aortic insufficiency (AI) patients with myocardial fibrosis. Method: This retrospective study included 59 AI patients who received CMR and transthoracic echocardiography (TTE) examinations from June 2011 to February 2015. AI patients were divided into 2 groups: bicuspid aortic valve (BAV) group (n=30) and non-BAV group (n=29). Patients were also divided into late gadolinium enhancement (LGE) group (n=27) and non-LGE group (n=32). The baseline clinical characteristics were collected through electronic medical records. Hemodynamic parameters such as grade of AI, cardiac functional parameters and LGE mass fraction (LGE%) were measured by CMR post-processing analysis. Kappa test was used to assess the consistency of AI severity between CMR and TTE, and the multivariate logistic regression analysis was performed to evaluate influence factors of myocardial fibrosis in AI patients. Results: (1) 56 (94.9%) patients were male, and the mean age was (44.2±11.0) years old. There was no significant difference in age and gender, hypertension, hyperlipidemia, alcoholic consumption between BAV and non-BAV group (all P>0.05). There were a higher proportion of smoking history (P=0.008), a lower body mass index (BMI) (P=0.020) in the LGE group than in the non-LGE group. (2) The accuracy of CMR in diagnosis of BAV was 96.7% (29/30) compared to the gold standard. In the BAV group, 20 patients (66.7%) were with fusion of left and right cusp (L-R), 5 patients (16.7%) were with fusion of right and noncoronary cusp (R-N), 5 patients (16.7%) were with fusion of left and noncoronary cusp (L-N); patients with BAV had larger left ventricular end diastolic volume index (LVEDVi), left ventricular end systolic volume index (LVESVi), higher proportion of LGE and lower left ventricular ejection fraction (LVEF) than those in non-BAV group (all P<0.05). There were 19 patients with BAV in the LGE group, the cases of L-R, R-N, L-N were 10 (52.6%), 5 (26.3%), and 4 (21.1%), respectively. In the non-LGE group, patients with BAV of L-R, R-N, L-N were 10 (90.9%), 0, and 1 (9.1%), respectively. Patients with LGE had lower body surface area (BSA), LVEF and larger LVEDVi, LVESVi, left ventricular mass index (LVMi) and higher proportion of BAV compared patients without LGE. In addition, the proportion of moderate and severe AI patients was significantly higher in BAV group than in non-BAV group (P=0.009). (3) The consistency of CMR and TTE in evaluating the severity of AI patients: the agreement between TTE and CMR regarding AI severity was satisfactory (kappa value was 0.624, 95%CI 0.402-0.831, P<0.001). (4) The linear regression analysis demonstrated a negative correlation between LVEF and LGE% in BAV and non-BAV group (P<0.001). The multivariate logistic regression analysis showed that the presence of BAV was an independent risk factor of left ventricucar fibrosis (OR=5.050, 95%CI 1.220-20.908, P=0.025) after adjustment for LVEF, hypertension, LVEDVi and LVMi. Conclusion: Multi-parametric CMR provides a satisfactory noninvasive tool for estimation of myocardial fibrosis and ventricular remodeling in patients with AI, and BAV is an independent risk factor for myocardial fibrosis in patients with AI.


Assuntos
Miocárdio , Adulto , Meios de Contraste , Feminino , Fibrose , Gadolínio , Humanos , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Retrospectivos , Volume Sistólico , Função Ventricular Esquerda
15.
Chem Commun (Camb) ; 55(72): 10784-10787, 2019 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-31432802

RESUMO

Medical magnetic resonance imaging (MRI) produces high-resolution anatomical images of the human body, but has limited capacity to provide useful molecular information. The light-responsive, liposomal MRI contrast agent described herein could be used to provide an intrinsic theranostic aspect to MRI and enable tracking the distribution and cargo release of drug delivery systems upon light-triggered activation.


Assuntos
Meios de Contraste/química , Sistemas de Liberação de Medicamentos , Gadolínio/química , Luz , Imagem por Ressonância Magnética , Humanos , Lipossomos/química , Estrutura Molecular
16.
Zhonghua Xin Xue Guan Bing Za Zhi ; 47(7): 534-538, 2019 Jul 24.
Artigo em Chinês | MEDLINE | ID: mdl-31365993

RESUMO

Objective: To evaluate the clinical and cardiac magnetic resonance (CMR) features of apical hypertrophic cardiomyopathy (ApHCM) patients complicating with left ventricular apical aneurysm (LVAA). Methods: CMR confirmed 25 ApHCM patients complicating with LVAA from January 2010 to December 2017 in Fuwai hospital were included in this study, and the baseline clinical data and CMR characteristics were retrospectively analyzed. There were 14 pure ApHCM (hypertrophy limited at the apical segments) complicating with LVAA patients and 11 mixed ApHCM (predominantly apical hypertrophy along with thickening of contiguous non-apical left ventricular region) with LVAA patients. Results: In this patient cohort,age of 84% (21/25) patients ranged between 20-70 years old, and 68% (17/25) were male. There were 68% (17/25) patients with complaint of chest distress symptom, 56% (14/25) with complaint of chest pain, 32% (8/25) with complaint of palpitation,16% (4/25) with complaint of dyspnea, and 12% (3/25) presented as syncope. ST-T segment changes of electrocardiogram were observed in all patients, and giant negative T waves were detected in 80% patients (20/25). The rate of missed diagnosis by echocardiography for detecting ApHCM and LVAA was 16% (4/25) and 68% (17/25), respectively. CMR showed discrete thin-walled dyskinetic or akinetic segment of the most distal portion of the left ventricular chamber in ApHCM patients with LVAA. Transmural late gadolinium enhancement of the aneurysmal rim was detected in 76% (19/25) patients, and the maximum transverse dimension of aneurysm was bigger in patients with transmural late gadolinium enhancement than in patients without transmural late gadolinium enhancement ((22.0±10.8)mm vs. (11.7±4.0) mm, P=0.033). Conclusion: ApHCM with LVAA patients have distinct cardiac clinical features, and CMR is the most useful tool for the accurate and objective evaluation of this disease.


Assuntos
Cardiomiopatia Hipertrófica , Meios de Contraste , Adulto , Idoso , Eletrocardiografia , Feminino , Gadolínio , Humanos , Espectroscopia de Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
18.
Can Assoc Radiol J ; 70(3): 226-232, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31255393

RESUMO

In 2017, the Canadian Association of Radiologists issued a clinical practice guideline (CPG) regarding the use of gadolinium-based contrast agents (GBCAs) in patients with acute kidney injury (AKI), chronic kidney disease (CKD), or on dialysis due to mounting evidence indicating that nephrogenic systemic fibrosis (NSF) occurs with extreme rarity or not at all when using Group II GBCAs or the Group III GBCA gadoxetic acid (compared to first generation Group I linear GBCAs). One of the goals of the work group was to re-evaluate the CPG after 24 months to determine the effect of more liberal use of GBCA on reported cases of NSF in patients with AKI, CKD Stage 4 or 5 (estimated glomerular filtration rate [eGFR] < 30 mL/min/1.73 m2), or those that are dialysis-dependent. A comprehensive review of the literature was conducted by a subcommittee of the initial CPG panel between the dates of January 1, 2017-December 31, 2018 to identify new unconfounded cases of NSF linked to Group II or Group III GBCAs and an updated CPG developed. To our knowledge, when using a Group II or Group III GBCA between 2017-2018, only a single unconfounded case report of a fibrosing dermopathy has been reported in a patient who received gadobenate dimeglumine with Stage 2 CKD. No other unconfounded cases of NSF have been reported with Group II or III agents in during this timeframe. The subcommittee concluded that the main recommendations from the 2017 CPG should remain unaltered, but agreed that screening for renal disease in the outpatient setting is no longer justifiable, cost-effective or recommended. Patients on hemodialysis (HD) should, however, be identified prior to GBCA administration to arrange timely HD to optimize gadolinium clearance, although there remains no evidence that HD reduces the risk of NSF. When administering Group II or III GBCAs to patients with AKI, on dialysis or with severe CKD, informed consent relating to NSF is also no longer explicitly recommended.


Assuntos
Meios de Contraste , Gadolínio , Aumento da Imagem/métodos , Nefropatias/diagnóstico por imagem , Imagem por Ressonância Magnética , Canadá , Humanos , Rim/diagnóstico por imagem , Radiologistas , Sociedades Médicas
19.
J Clin Neurosci ; 67: 215-219, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31281087

RESUMO

We formulated an ultra-small, gadolinium-based nanoparticle (AGuIX) with theranostic properties to simultaneously enhance MRI tumor delineation and radiosensitization in a glioma model. The 9L glioma cells were orthotopically implanted in 10-week-old Fischer rats. The intra-tumoral accumulation of AGuIX was quantified using MRI T1-maps. Rats randomized to intervention cohorts were subsequently treated with daily temozolomide for five consecutive days before radiotherapy treatment. Collectively, a series of 32 rats were divided into untreated (n = 7), temozolomide-only (n = 7), temozolomide and MRT (n = 9), AGuIX and MRT (n = 7), and triple therapy (temozolomide, AGuIX NPs, and MRT; n = 9) cohorts. AGuIX nanoparticles achieved a maximum intra-tumoral concentration (expressed as concentration of Gd3+) at 1 h after intravenous injection, reaching a mean of 227.9 ±â€¯60 µM. This was compared to concentrations of 10.5 ±â€¯9.2 µM and 62.9 ±â€¯24.7 µM in the contralateral hemisphere and cheek, respectively. There was a slower washout in the intra-tumor region, with sustained tumor-to-contralateral ratio of AGuIX, up to 14-fold, for each time point. The combination of AGuIX or temozolomide with MRT improved the median survival time (40 days) compared to the MeST of control rats (25 days) (p < 0.002). There was a trend towards further increased survival when the three treatments were combined (MeST of 46 days). This study demonstrated the selective accumulation of AGuIX in high grade glioma, as well as the potential survival benefits when combined with chemoradiation.


Assuntos
Neoplasias Encefálicas/patologia , Gadolínio , Glioma/patologia , Radiossensibilizantes/farmacologia , Nanomedicina Teranóstica , Animais , Quimiorradioterapia/métodos , Meios de Contraste/farmacologia , Imagem por Ressonância Magnética/métodos , Masculino , Nanopartículas , Ratos , Ratos Endogâmicos F344 , Temozolomida/farmacologia
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