High-risk plaque in the superficial femoral artery of people with peripheral artery disease: prevalence and associated clinical characteristics.

Objective: We used magnetic resonance imaging (MRI) to study the prevalence and associated clinical characteristics of high-risk plaque (defined as presence of lipid-rich necrotic core [LRNC] and intraplaque hemorrhage) in the superficial femoral arteries (SFA) among people with peripheral artery disease (PAD).

Background: The prevalence and clinical characteristics associated with high-risk plaque in the SFA are unknown.

Methods: Three-hundred-three participants with PAD underwent MRI of the proximal SFA using a 1.

Carotid magnetic resonance imaging for monitoring atherosclerotic plaque progression: a multicenter reproducibility study.

This study sought to determine the multicenter reproducibility of magnetic resonance imaging (MRI) and the compatibility of different scanner platforms in assessing carotid plaque morphology and composition. A standardized multi-contrast MRI protocol was implemented at 16 imaging sites (GE: 8; Philips: 8). Sixty-eight subjects (61 ± 8 years; 52 males) were dispersedly recruited and scanned twice within 2 weeks on the same magnet.

Scan-rescan reproducibility of quantitative assessment of inflammatory carotid atherosclerotic plaque using dynamic contrast-enhanced 3T CMR in a multi-center study.

Background: The aim of this study is to investigate the inter-scan reproducibility of kinetic parameters in atherosclerotic plaque using dynamic contrast-enhanced (DCE) cardiovascular magnetic resonance (CMR) in a multi-center setting at 3T.

Methods: Carotid arteries of 51 subjects from 15 sites were scanned twice within two weeks on 3T scanners using a previously described DCE-CMR protocol. Imaging data with protocol compliance and sufficient image quality were analyzed to generate kinetic parameters of vessel wall, expressed as transfer constant (K trans ) and plasma volume (v p ).

Collateral vessel number, plaque burden, and functional decline in peripheral artery disease.

Associations of collateral vessels and lower extremity plaque with functional decline are unknown. Among people with peripheral artery disease (PAD), we determined whether greater superficial femoral artery (SFA) plaque burden combined with fewer lower extremity collateral vessels was associated with faster functional decline, compared to less plaque and/or more numerous collateral vessels. A total of 226 participants with ankle-brachial index (ABI) <1.

Prenatal androgen excess enhances stimulation of the GNRH pulse in pubertal female rats.

In adolescent girls with polycystic ovary syndrome (PCOS), neuroendocrine derangements manifest after the onset of puberty, characterized by rapid LH pulse frequency. The early mechanism underlying the pubertal regulation of the GNRH/LH pulsatile release in adolescents with PCOS remains uncertain. To determine the effects of prenatal androgen exposure on the activation of GNRH neurons and generation of LH pulse at puberty, we administrated 5α-dihydrotestosterone to pregnant rats and observed serum LH levels and expression of hypothalamic genes in female offspring from postnatal 4 to 8 weeks.

Parallel imaging and compressed sensing combined framework for accelerating high-resolution diffusion tensor imaging using inter-image correlation.

Purpose: Increasing acquisition efficiency is always a challenge in high-resolution diffusion tensor imaging (DTI), which has low signal-to-noise ratio and is sensitive to reconstruction artifacts. In this study, a parallel imaging (PI) and compressed sensing (CS) combined framework is proposed, which features motion error correction, PI calibration, and sparsity model using inter-image correlation tailored for high-resolution DTI.

Theory And Methods: The proposed method, named anisotropic sparsity SPIRiT, consists of three steps: (i) motion-induced phase error estimation, (ii) initial CS reconstruction and PI kernel calibration, and (iii) final reconstruction combining PI and CS.

Homologous HOmologous Black-Bright-blood and flexible Interleaved imaging sequence (HOBBI) for dynamic contrast-enhanced MRI of the vessel wall.

Purpose: To present a HOmologous Black-Bright-blood and flexible Interleaved imaging (HOBBI) sequence for dynamic contrast-enhanced magnetic resonance imaging (MRI) of the vessel wall.

Theory And Methods: A HOBBI sequence is proposed to acquire high-spatial-resolution black-blood and high-temporal-resolution bright-blood dynamic contrast-enhanced images in an interleaved fashion. Black-blood imaging allows for thin vessel wall evaluation, whereas bright-blood imaging obtains the arterial input function accurately.

Varying correlation between 18F-fluorodeoxyglucose positron emission tomography and dynamic contrast-enhanced MRI in carotid atherosclerosis: implications for plaque inflammation.

Background And Purpose: (18)F-fluorodeoxyglucose positron emission tomography and dynamic contrast-enhanced MRI have been proposed to quantitatively assess plaque inflammation by probing macrophages and neovessels, respectively. We examined their correlation to study the in vivo relationship between macrophage and neovessel activities in atherogenesis.

Methods: Forty-one patients (34 men; aged 65±12 years) with a total of 68 carotid plaques (thickness ≥2 mm on ultrasound; 20 symptomatic) were assessed by both (18)F-fluorodeoxyglucose positron emission tomography/computed tomography and dynamic contrast-enhanced MRI within 2 weeks, measured as target-to-background ratio and transfer constant (K(trans)), respectively.

Associations of arterial distensibility between carotid arteries and abdominal aorta by MR.

Purpose: To investigate the correlations of arterial distensibility between carotid arteries and abdominal aorta by MR.

Materials And Methods: Twenty eight asymptomatic old subjects (71.4 ± 6.

Magnetic Resonance Imaging Tracking of Graft Survival in the Infarcted Heart: Iron Oxide Particles Versus Ferritin Overexpression Approach.

The main objective of cell therapy is the regeneration of damaged tissues. To distinguish graft from host tissue by magnetic resonance imaging (MRI), a paramagnetic label must be introduced to cells prior to transplantation. The paramagnetic label can be either exogenous iron oxide nanoparticles or a genetic overexpression of ferritin, an endogenous iron storage protein.

Prediction of high-risk plaque development and plaque progression with the carotid atherosclerosis score.

Objectives: The goal of this prospective study was to evaluate the carotid atherosclerosis score (CAS) for predicting the development of high-risk plaque features and plaque burden progression.

Background: Previous studies have shown that carotid intraplaque hemorrhage (IPH) and a disrupted luminal surface (DLS), as identified by using magnetic resonance imaging, are associated with greater risk for cerebrovascular events. On the basis of data from a large cross-sectional study, a scoring system was developed to determine which plaque features are associated with the presence of IPH and DLS.

PROMISE: parallel-imaging and compressed-sensing reconstruction of multicontrast imaging using SharablE information.

Purpose: A typical clinical MR examination includes multiple scans to acquire images with different contrasts for complementary diagnostic information. The multicontrast scheme requires long scanning time. The combination of partially parallel imaging and compressed sensing (CS-PPI) has been used to reconstruct accelerated scans.

Image-based modeling for better understanding and assessment of atherosclerotic plaque progression and vulnerability: data, modeling, validation, uncertainty and predictions.

Medical imaging and image-based modeling have made considerable progress in recent years in identifying atherosclerotic plaque morphological and mechanical risk factors which may be used in developing improved patient screening strategies. However, a clear understanding is needed about what we have achieved and what is really needed to translate research to actual clinical practices and bring benefits to public health. Lack of in vivo data and clinical events to serve as gold standard to validate model predictions is a severe limitation.

Referenceless acquisition of phase-sensitive inversion-recovery with decisive reconstruction (RAPID) imaging.

Purpose: To describe a referenceless reconstruction approach to generate phase-sensitive inversion recovery images without relying on the extra acquisition of reference images.

Methods: The basic idea of the Referenceless Acquisition of Phase-sensitive Inversion-recovery with Decisive reconstruction, or RAPID, algorithm is to retrieve the magnetization polarity by estimating the background phase variation of a complex valued image. The theory and algorithm of RAPID is described in detail.

Atherosclerotic plaque inflammation quantification using dynamic contrast-enhanced (DCE) MRI.

Inflammation plays an important role in atherosclerosis. Given the increasing interest in using in-vivo imaging methods to study the physiology and treatment effects in atherosclerosis, noninvasive intraplaque inflammation quantitative method is needed. Dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) has been proposed and validated to quantitatively characterize atherosclerotic plaque inflammation.

Molecular characterization and identification of Th1 epitopes of a Schistosoma japonicum protein similar to prosaposin.

The tegument of schistosomula contains T cell antigens that might simulate the protective mechanisms of the radiation-attenuated vaccine in a mouse model of schistosomiasis. Immune mechanisms mediated by the CD4+ Th1 response are important in the RAV model. To rapidly identify Th1 epitopes in molecules from the Schistosoma japonicum schistosomula tegument, this study analyzed S.

Clinical progression and predictors of death in patients with severe fever with thrombocytopenia syndrome in China.

Background: Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease of which the clinical progression and factors related to death are still unclear.

Objective: To identify the clinical progression of SFTS and explore predictors of fatal outcome throughout the disease progress.

Study Design: A prospective study was performed in a general hospital located in Xinyang city during 2011-2013.

Correlations between carotid plaque progression and mechanical stresses change sign over time: a patient follow up study using MRI and 3D FSI models.

Background: Increasing evidence suggests that mechanisms governing advanced plaque progression may be different from those for early progression and require further investigation. Serial MRI data and 3D fluid-structure interaction (FSI) models were employed to identify possible correlations between mechanical stresses and advanced plaque progression measured by vessel wall thickness increase (WTI). Long-term patient follow up was used to gather data and investigate if the correlations identified above were reproducible.

Improved motion correction in PROPELLER by using grouped blades as reference.

Purpose: To develop a robust reference generation method for improving PROPELLER (Periodically Rotated Overlapping ParallEL Lines with Enhanced Reconstruction) reconstruction.

Materials And Methods: A new reference generation method, grouped-blade reference (GBR), is proposed for calculating rotation angle and translation shift in PROPELLER. Instead of using a single-blade reference (SBR) or combined-blade reference (CBR), our method classifies blades by their relative correlations and groups similar blades together as the reference to prevent inconsistent data from interfering the correction process.

Molecular MRI of atherosclerotic plaque progression in an ApoE(-/-) mouse model with a CLT1 peptide targeted macrocyclic Gd(III) chelate.

Molecular imaging of atherosclerotic biomarkers is critical for non-invasive detection and diagnosis of atherosclerotic plaques and therapeutic management. Fibrin and fibronectin accumulate at elevated levels in atherosclerotic plaques and are associated with atherogenesis and disease progression. Molecular imaging of these biomarkers has the potential to non-invasively characterize plaque burden.

Case-fatality ratio and effectiveness of ribavirin therapy among hospitalized patients in china who had severe fever with thrombocytopenia syndrome.

Background: The wide distribution and high case-fatality ratio of severe fever with thrombocytopenia syndrome (SFTS) have made it a significant public health problem. This study was designed to identify the predictors of fatal outcomes and to evaluate the effectiveness of antiviral therapy in treating SFTS virus (SFTSV)-infected patients.

Methods: A cross-sectional study was performed in a general hospital located in Xinyang city, whereas the largest number of patients with SFTS in China were treated during 2011-2012.

A framework for the co-registration of hemodynamic forces and atherosclerotic plaque components.

Local hemodynamic forces, such as wall shear stress (WSS), are thought to trigger cellular and molecular mechanisms that determine atherosclerotic plaque vulnerability to rupture. Magnetic resonance imaging has emerged as a powerful tool to characterize human carotid atherosclerotic plaque composition and morphology, and to identify plaque features shown to be key determinants of plaque vulnerability. Image-based computational fluid dynamics has allowed researchers to obtain time-resolved WSS information of atherosclerotic carotid arteries.

Meta-analysis and systematic review of the predictive value of carotid plaque hemorrhage on cerebrovascular events by magnetic resonance imaging.

Objectives: This study sought to conduct a systematic review and meta-analysis to determine precise estimates of the predictive value of carotid intraplaque hemorrhage (IPH) as determined by magnetic resonance imaging (MRI) for cerebrovascular events.

Background: There is emerging evidence that MR-based carotid atherosclerotic plaque assessment identifies high-risk features associated with cerebrovascular events. However, available data are based on smaller samples with heterogeneous source populations despite a promising value for noninvasive risk stratification.

Comparison of symptomatic and asymptomatic atherosclerotic carotid plaques using parallel imaging and 3 T black-blood in vivo CMR.

Background: To determine if black-blood 3 T cardiovascular magnetic resonance (bb-CMR) can depict differences between symptomatic and asymptomatic carotid atherosclerotic plaques in acute ischemic stroke patients.

Methods: In this prospective monocentric observational study 34 patients (24 males; 70 ±9.3 years) with symptomatic carotid disease defined as ischemic brain lesions in one internal carotid artery territory on diffusion weighted images underwent a carotid bb-CMR at 3 T with fat-saturated pre- and post-contrast T1w-, PDw-, T2w- and TOF images using surface coils and Parallel Imaging techniques (PAT factor = 2) within 10 days after symptom onset.