Format
Sort by
Items per page

Send to

Choose Destination

Search results

Items: 1 to 20 of 70

1.
Eur Radiol. 2018 Jul 9. doi: 10.1007/s00330-018-5612-y. [Epub ahead of print]

BOLD cardiac MRI for differentiating reversible and irreversible myocardial damage in ST segment elevation myocardial infarction.

Author information

1
Department of Radiology, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, No.160 PuJian Road, Shanghai, 200127, People's Republic of China.
2
Department of Radiology, Wayne State University, Detroit, MI, 48201, USA.
3
Department of Cardiology, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, 200127, People's Republic of China.
4
Department of Radiology, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, No.160 PuJian Road, Shanghai, 200127, People's Republic of China. xujianrong0311@126.com.
5
Department of Radiology, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, No.160 PuJian Road, Shanghai, 200127, People's Republic of China. wlmssmu@126.com.

Abstract

OBJECTIVES:

BOLD imaging is a quantitative MRI technique allowing the evaluation of the balance between supply/demand in myocardial oxygenation and myocardial haemorrhage. We sought to investigate the ability of BOLD imaging to differentiate reversible from irreversible myocardial injury as well as the chronological progression of myocardial oxygenation after reperfusion in patients with ST segment elevation myocardial infarction (STEMI).

METHODS:

Twenty-two patients (age, 60 ± 11 years; 77.3% male) with STEMI underwent cardiac MRIs on four occasions: on days 1, 3, 7 and 30 after reperfusion. BOLD MRI was obtained with a multi-echo turbo field echo (TFE) sequence on a 3-T scanner to assess myocardial oxygenation in MI.

RESULTS:

T2* value in MI with intramyocardial haemorrhage (IMH) was the lowest (9.77 ± 3.29 ms), while that of the salvaged zone was the highest (33.97 ± 3.42 ms). T2* values in salvaged myocardium demonstrated a unimodal temporal pattern from days 1 (37.91 ± 2.23 ms) to 30 (30.68 ± 1.59 ms). T2* values in the MI regions were significantly lower than those in remote myocardium, although the trends in both were constant overall. There was a slightly positive correlation between T2* in MI regions and EF (Rho = 0.27, p < 0.05) or SV (Rho = 0.22, p = 0.04) and a slightly negative correlation between T2* in salvaged myocardium and LVEDV (Rho = - 0.23, p < 0.05).

CONCLUSIONS:

BOLD MRI performed in post-STEMI patients allows accurate evaluation of myocardial damage severity and could differentiate reversible from irreversible myocardial injury. The increased T2* values may imply the pathophysiological mechanism of salvaged myocardium. BOLD MRI could represent a more accurate alternative to the other currently available options.

KEY POINTS:

• Myocardial oxygenation and haemorrhage after myocardial infarction affect BOLD MRI values • BOLD MRI could be used to differentiate irreversible from reversible myocardial damage • Changed oxygenation implies the pathophysiological mechanism of salvaged myocardium.

KEYWORDS:

Haemoglobins; Magnetic resonance imaging; Myocardium; Reperfusion; ST elevation myocardial infarction

2.
Basic Clin Pharmacol Toxicol. 2018 May 21. doi: 10.1111/bcpt.13042. [Epub ahead of print]

IL-6 Triggers the Migration and Invasion of Oestrogen Receptor-Negative Breast Cancer Cells via Regulation of Hippo Pathways.

Author information

1
Breast Disease Center, Southwest Hospital, Army Medical University, Chongqing, China.
2
Department of Thyroid and Breast Surgery, The First Affiliated Hospital of Chengdu Medical College, Chengdu, Sichuan, China.
3
Department of Thyroid Breast Surgery, The Affiliated Hospital of North Sichuan Medical College, Nanchong, Sichuan, China.
4
Department of Radiology, Yueyang Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China.
5
Department of Radiology, Wayne State University, Detroit, MI, USA.
6
Department of Anatomy, The North Sichuan Medical College, Nanchong, Sichuan, China.

Abstract

Breast cancer is one of the major challenges for women's health. However, the role and mechanisms of interleukins (ILs) on the progression of breast cancer are not well illustrated. Our present study revealed that the expressions of IL-6 and IL-8 were significantly increased in oestrogen receptor-negative (ER-) breast cancer cells. Increased expression of IL-6 was observed in 83.9% (26/31) ER- breast cancer tissues as compared with their matched adjacent normal tissues. In vitro studies indicated that IL-6 can significantly promote the migration and invasion of ER- breast cancer cells via increasing the dephosphorylation, nuclear translocation and transcriptional activities of YAP in breast cancer cells. Knockdown of YAP can attenuate IL-6-induced migration and invasion of cancer cells, suggesting that YAP plays an essential role in IL-6-induced malignancy of breast cancer cells. Furthermore, IL-6 treatment also decreased the phosphorylation of LATS1/2. The knockdown of LATS1/2 synergistically suppressed si-IL-6-induced deactivation of YAP. Targeted inhibition of IL-6/YAP can significantly suppress the invasion of ER- breast cancer cells. Collectively, our study revealed that IL-6 can trigger the malignancy of breast cancer cells via activation of YAP signals. Targeted inhibition of IL-6/YAP might be a novel therapeutic approach for the treatment of ER- breast cancer.

3.
J Magn Reson Imaging. 2018 May 7. doi: 10.1002/jmri.26055. [Epub ahead of print]

Oxygenation-sensitive cardiovascular magnetic resonance in hypertensive heart disease with left ventricular myocardial hypertrophy and non-left ventricular myocardial hypertrophy: Insight from altered mechanics and cardiac BOLD imaging.

Author information

1
Department of Radiology, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China.
2
Department of Radiology, Wayne State University, Detroit, Michigan, USA.
3
Department of Cardiology, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China.

Abstract

BACKGROUND:

BOLD (blood oxygen level dependent) MRI can detect regional condition of myocardial oxygen supply and demand by means of paramagnetic properties.

PURPOSE:

Noninvasive assessment of myocardial oxygenation by BOLD MRI in hypertensive patients with hypertension (HTN) left ventricular myocardial hypertrophy (LVMH) and HTN non-LVMH and its correlation with myocardial mechanics were performed.

STUDY TYPE:

Prospective.

POPULATION:

Twenty patients with HTN LVMH, 21 patients with HTN non-LVMH, and 23 normotensive controls were enrolled.

FIELD STRENGTH/SEQUENCE:

Cine imaging, T2* and T1 mapping sequences were achieved at 3.0T.

ASSESSMENT:

Dedicated T1 mapping, T2*, and cine imaging analysis were performed by two radiologists using cvi42.

STATISTICAL TESTS:

One-way analysis of variance, Kruskal-Wallis test, Bland-Altman analysis, Pearson's correlation coefficient, Spearman's rank correlation.

RESULTS:

T2* values of HTN LVMH group were significantly lower versus the controls (23.78 ± 3.09 versus 30.77 ± 2.71; P < 0.001) and HTN non-LVMH group (23.78 ± 3.09 versus 28.64 ± 4.23; P < 0.001). Left ventricular peak circumferential strain were reduced in HTN LVMH patients compared with other two groups (-11.32 [-15.64, -10.3], -16.78 [-19.35, -15.34], and -19.73 [-20.57, -18.73]; P < 0.05); and longitudinal strain of HTN LVMH patients were lower than other two groups (-11.31 ± 2.91, -15.1 ± 3.06, and -18.85 ± 1.85; P < 0.05); radial strain of HTN LVMH patients were also lower than other two groups (25.03 ± 16, 40.95 ± 17.5 and 47.9 ± 10.23; P < 0.05). Extracellular volume correlated with peak circumferential, longitudinal, and radial strain (spearman rho = 0.6, 0.64, and -0.69; P < 0.05), respectively; T2* negatively correlated with peak circumferential and longitudinal strain (spearman rho = -0.43 and -0.49; P < 0.05), respectively. Patients with lower T2* values had significant decreases in myocardial mechanics (P < 0.05).

DATA CONCLUSION:

HTN LVMH patients have both impaired myocardial mechanics and decreased T2* values compared with HTN non-LVMH and normotensive groups. BOLD MRI could provide a feasible assessment modality for detecting altered T2* due to the change of de-oxygenated hemoglobin and hence to the change of signal intensity in oxygenation-sensitive images.

LEVEL OF EVIDENCE:

1 Technical Efficacy: Stage 3 J. Magn. Reson. Imaging 2018.

KEYWORDS:

blood oxygen level dependent; cardiac magnetic resonance imaging; hypertensive heart disease; myocardial strain

4.
J Magn Reson Imaging. 2018 May 7. doi: 10.1002/jmri.26179. [Epub ahead of print]

Diagnostic performance of intravoxel incoherent motion diffusion-weighted imaging in the assessment of the dynamic status of myocardial perfusion.

Author information

1
Department of Radiology, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China.
2
Department of Cardiology, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China.
3
Department of Radiology, Wayne State University, Detroit, Michigan, USA.

Abstract

BACKGROUND:

Acute myocardial infarction (AMI) is a major cause of morbidity and mortality worldwide and places a significant financial burden on our society.

PURPOSE:

To determine the feasibility of cardiac intravoxel incoherent motion (IVIM) in the consecutive evaluation of myocardial perfusion in myocardial infarction patients postpercutaneous coronary intervention (PCI) and to investigate the dynamic biological phenomena in myocardial perfusion after AMI.

STUDY TYPE:

Prospective observational study.

POPULATION:

Twenty ST-segment elevation myocardial infarction (STEMI) patients after reperfusion therapy and 12 healthy volunteers served as controls.

FIELD STRENGTH/SEQUENCE:

Cardiac MRI at 3T, including steady-state free precession (SSFP) cine imaging, T2 -short time inversion recovery (T2 -STIR), late gadolinium enhancement (LGE), T2 mapping, and IVIM diffusion-weighted imaging (DWI) were performed.

ASSESSMENT:

Myocardial T2 value and IVIM-DWI-associated parameters (ADCfast , ADCslow , and f value) of the infarcted myocardium at different timepoints, remote myocardium, and normal myocardium were analyzed by two experienced radiologists.

STATISTICAL TESTS:

Independent sample's t-test, Pearson's, and Spearman's correlation and interobserver variability were applied. P ≤ 0.05 was considered significant.

RESULTS:

The T2 value in ischemic myocardium measured on day 3 (73.58 ± 4.37 msec) was greater than at any other timepoint (24 hours, day 7, day 30; 66.66 ± 4.71 msec, 68.36 ± 4.18 msec, 64.98 ± 5.39 msec, respectively, P < 0.001). ADCfast and f values were significantly lower in ischemic myocardium than in the remote myocardium as well. The f value in ischemic myocardium at day 3 (0.0989 ± 0.02) was lower than at any other timepoint (24 hours, 7 day, 30 day; 0.1203 ± 0.02, 0.1109 ± 0.02, 0.1213 ± 0.02, respectively, P < 0.001.

DATA CONCLUSION:

This preliminary study demonstrated that a dynamic process exists in the status of myocardial edema and myocardial perfusion in MI patients after PCI. The findings suggest myocardial perfusion would be best evaluated between day 3 and day 7.

LEVEL OF EVIDENCE:

2 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2018.

KEYWORDS:

AMI; IVIM; T2 mapping; late gadolinium enhanced imaging

5.
Quant Imaging Med Surg. 2018 Mar;8(2):123-134. doi: 10.21037/qims.2018.03.02.

Quantification of liver iron concentration using the apparent susceptibility of hepatic vessels.

Author information

1
The MRI Institute for Biomedical Research, Bingham Farms, MI, USA.
2
School of Biomedical Engineering, McMaster University, Hamilton, ON, Canada.
3
Department of Radiology, Tianjin First Central Hospital, Tianjin 300192, China.
4
Siemens Healthcare, MR Collaborations NE Asia, Beijing 100010, China.
5
Department of Radiology, Wayne State University, Detroit, MI, USA.

Abstract

Background:

The quantification of liver iron concentration (LIC) is important for the monitoring of the body iron level in patients with iron overload. Conventionally, LIC is quantified through R2 or R2* mapping using MRI. In this paper, we demonstrate an alternative approach for LIC quantification through measuring the apparent susceptibility of hepatic vessels using quantitative susceptibility mapping (QSM).

Methods:

QSM was performed in the liver region with the iterative susceptibility weighted imaging and mapping (iSWIM) algorithm, using the geometry of the vessels extracted from magnitude images as constraints. The susceptibilities of liver tissue were estimated from the apparent susceptibility of the hepatic veins and then converted to LIC. The accuracy of the proposed method was first validated using simulations, and then confirmed using in vivo data collected on 8 healthy controls and 11 patients at 3T. The effects of data acquisition parameters were studied using simulations, and the LICs estimated using QSM were compared with those estimated using R2* mapping.

Results:

Simulation results showed that the use of a 3D data acquisition protocol with higher image resolution led to improved accuracy in LIC quantification using QSM. Both simulations and in vivo data results demonstrated that the LICs estimated using the proposed QSM method agreed well with those estimated using R2* mapping. With the shortest echo time being 2.5ms in the multi-echo gradient echo sequence, simulations results showed that LIC up to 12.45 mg iron/g dry tissue can be quantified using the proposed QSM method. For the in vivo data, the highest LIC measured was 11.32 mg iron/g dry tissue.

Conclusions:

The proposed method offers a reliable and flexible way to quantify LIC and has the potential to extend the range of LIC that can be accurately measured using R2* and QSM.

KEYWORDS:

Liver iron concentration (LIC); R2* mapping; quantitative susceptibility mapping (QSM)

Conflict of interest statement

Conflicts of Interest: The authors have no conflicts of interest to declare.

6.
Contrast Media Mol Imaging. 2018 Feb 14;2018:6268437. doi: 10.1155/2018/6268437. eCollection 2018.

Neural Induction Potential and MRI of ADSCs Labeled Cationic Superparamagnetic Iron Oxide Nanoparticle In Vitro.

Author information

1
Medical Imaging Department, Nan Sha Center Hospital, Guangzhou Municipal First People's Hospital, Guangzhou Medical University, The Second Affiliated Hospital of South China University of Technology, Guangzhou, Guangdong 511457, China.
2
Department of Radiology, Huizhou Municipal Central Hospital, Huizhou, Guangdong 516001, China.
3
School of Materials Science and Engineering, Guilin University of Technology, Guilin, Guangxi 541004, China.
4
Karmanos Cancer Institute, Wayne State University, 3990 John R. Street, Detroit, MI 48201, USA.

Abstract

Magnetic resonance imaging (MRI) combined with contrast agents is believed to be useful for stem cell tracking in vivo, and the aim of this research was to investigate the biosafety and neural induction of SD rat-originated adipose derived stem cells (ADSCs) using cationic superparamagnetic iron oxide (SPIO) nanoparticle which was synthesized by the improved polyol method, in order to allow visualization using in vitro MRI. The scan protocols were performed with T2-mapping sequence; meanwhile, the ultrastructure of labeled cells was observed by transmission electron microscopy (TEM) while the iron content was measured by inductively coupled plasma-atomic emission spectrometry (ICP-AES). After neural induction, nestin and NSE (neural markers) were obviously expressed. In vitro MRI showed that the cationic PEG/PEI-modified SPIO nanoparticles could achieve great relaxation performance and favourable longevity. And the ICP-AES quantified the lowest iron content that could be detected by MRI as 1.56~1.8 pg/cell. This study showed that the cationic SPIO could be directly used to label ADSCs, which could then inductively differentiate into nerve and be imaged by in vitro MRI, which would exhibit important guiding significance for the further in vivo MRI towards animal models with neurodegenerative disorders.

7.
J Magn Reson Imaging. 2018 Mar 30. doi: 10.1002/jmri.26016. [Epub ahead of print]

Myocardial fibrosis evaluated by diffusion-weighted imaging and its relationship to 3D contractile function in patients with hypertrophic cardiomyopathy.

Author information

1
Department of Radiology, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China.
2
Department of Cardiology, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China.
3
Department of Physical Medicine and Rehabilitation, Detroit Medical Center, Detroit, Michigan, USA.
4
Circle Cardiovascular Imaging Inc., Calgary, AB, Canada.
5
Department of Radiology, Wayne State University, Detroit, Michigan, USA.

Abstract

BACKGROUND:

Previous studies have shown that diffusion-weighted imaging (DWI) is sensitive to myocardial fibrosis in ischemic and nonischemic cardiomyopathy.

PURPOSE:

To explore the prognostic value of apparent diffusion coefficient (ADC) for detecting myocardial fibrosis and its relationship to the contractile function in hypertrophic cardiomyopathy (HCM).

STUDY TYPE:

Prospective.

POPULATION:

A total of 45 HCM patients and 20 controls.

FIELD STRENGTH/SEQUENCE:

3.0T cardiac MRI. The cardiac MR sequences included cine, T1 mapping, and DWI.

ASSESSMENT:

According to the presence of late gadolinium enhancement (LGE) and the extracellular volume (ECV) values (+2 SD of control subjects), respectively, reader W and reader J assessed the value of ADC of each segment for detecting myocardial fibrosis and its relationship to impaired contractile function in HCM patients.

STATISTICAL TESTS:

Independent sample t-test, Pearson analysis, and intraclass correlation (ICC).

RESULTS:

The value of ECV was 23.6 ± 3.0% for control. ECV ≥ 29.6% and ECV < 29.6% groups were classified. ADC values in the ECV ≥ 29.6% group were significantly increased compared to the ECV < 29.6% group, (2.41 ± 0.23 μm2 /ms vs. 2.03 ± 0.16 μm2 /ms, P < 0.005). Compared to the LGE - group, ECV (32.1 ± 2.3% vs. 29.0 ± 2.8%, P < 0.005) and ADC (2.60 ± 0.18 μm2 /ms vs. 2.10 ± 0.07 μm2 /ms, P < 0.005) values were significantly increased in the LGE + group. ADC values were linearly associated with ECV values (R2  = 0.65) in HCM patients. ADC values were linearly associated with circumferential and longitudinal strain (R2  = 0.60, R2  = 0.46), as well as circumferential, longitudinal, and radial strain rate (R2  = 0.13, R2  = 0.25, R2  = 0.17, respectively).

DATA CONCLUSION:

Contractile dysfunction in HCM is predominantly associated with ADC, which is a feasible alternative to ECV and LGE for detecting myocardial fibrosis.

LEVEL OF EVIDENCE:

1 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2018.

KEYWORDS:

DWI; ECV; HCM; LGE; apparent diffusion coefficient; tissue tracking

8.
Biomed Microdevices. 2018 Feb 19;20(1):21. doi: 10.1007/s10544-018-0268-6.

Flexible 3D carbon nanotubes cuff electrodes as a peripheral nerve interface.

Author information

1
State Key Laboratory of Mechanical System and Vibration, Shanghai Jiao Tong University, Shanghai, China.
2
Electrical and Computer Engineering, Wayne State University, Detroit, MI, USA.
3
Department of Biomedical Engineering, Wayne State University, Detroit, MI, USA.
4
State Key Laboratory of Mechanical System and Vibration, Shanghai Jiao Tong University, Shanghai, China. hujie@sjtu.edu.cn.
5
Electrical and Computer Engineering, Wayne State University, Detroit, MI, USA. mcheng@wayne.edu.
6
Department of Biomedical Engineering, Wayne State University, Detroit, MI, USA. mcheng@wayne.edu.

Abstract

The cuff electrode provides a stable interface with peripheral nerves, which has been widely used in basic research and clinical practice. Currently, the cuff electrodes are limited by the planar processing of microfabrication. This paper presents a novel cuff electrode using high-aspect ratio carbon nanotubes (CNTs) integrated on a flexible biocompatible parylene. The microfabrication process unites the high quality vertical CNTs grown at high temperature with the heat sensitive parylene substrate in a highly controllable manner. The fabricated cuff electrodes have been utilized for extracellular nerve stimulation in rats. The experimental results demonstrate the proposed CNT electrode has a better performance than Pt electrode in nerve stimulation. Moreover, the effect of electrode position and stimulation frequency is demonstrated in this paper. This preliminary data indicates that flexible 3D CNTs cuff electrode provides an excellent platform for functional electrical stimulation.

KEYWORDS:

Carbon nanotubes; Cuff electrode; Parylene; Peripheral nerve interface

9.
Biomed Res Int. 2017;2017:6258395. doi: 10.1155/2017/6258395. Epub 2017 Nov 5.

Erratum to "Automatic Segmentation of Ultrasound Tomography Image".

Wu S1,2, Yu S1,2, Zhuang L3, Wei X4, Sak M5,6, Duric N5,6, Hu J7, Xie Y1.

Author information

1
Institute of Biomedical and Health Engineering, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, 1068 Xueyuan Avenue, Shenzhen University Town, Shenzhen 518055, China.
2
Shenzhen Colleges of Advanced Technology, University of Chinese Academy of Sciences, 1068 Xueyuan Avenue, Shenzhen University Town, Shenzhen 518055, China.
3
Department of Radiation Oncology, Northwestern Medicine Lake Forest Hospital, Lake Forest, IL 60045, USA.
4
Department of Radiology, Guangzhou First Hospital, Guangzhou Medical University, Guangzhou 510180, China.
5
Department of Oncology, The Karmanos Cancer Institute, Wayne State University, Detroit, MI 48201, USA.
6
Delphinus Medical Technologies, Inc., Plymouth, MI 48170, USA.
7
Department of Radiology, Wayne State University, Detroit, MI 48201, USA.

Abstract

[This corrects the article DOI: 10.1155/2017/2059036.].

10.
Biomed Microdevices. 2017 Nov 23;20(1):4. doi: 10.1007/s10544-017-0247-3.

A novel fabrication method of carbon electrodes using 3D printing and chemical modification process.

Author information

1
State Key Laboratory of Mechanical System and Vibration, Shanghai Jiao Tong University, Shanghai, China.
2
Department of Biomedical Engineering, Wayne State University, Detroit, MI, USA.
3
State Key Laboratory of Mechanical System and Vibration, Shanghai Jiao Tong University, Shanghai, China. hujie@sjtu.edu.cn.
4
Engineering Technology, Wayne State University, Detroit, MI, USA.
5
Department of Biomedical Engineering, Wayne State University, Detroit, MI, USA. mcheng@wayne.edu.
6
Electrical and Computer Engineering, Wayne State University, Detroit, MI, USA. mcheng@wayne.edu.

Abstract

Three-dimensional (3D) printing is an emerging technique in the field of biomedical engineering and electronics. This paper presents a novel biofabrication method of implantable carbon electrodes with several advantages including fast prototyping, patient-specific and miniaturization without expensive cleanroom. The method combines stereolithography in additive manufacturing and chemical modification processes to fabricate electrically conductive carbon electrodes. The stereolithography allows the structures to be 3D printed with very fine resolution and desired shapes. The resin is then chemically modified to carbon using pyrolysis to enhance electrochemical performance. The electrochemical characteristics of 3D printing carbon electrodes are assessed by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The specific capacitance of 3D printing carbon electrodes is much higher than the same sized platinum (Pt) electrode. In-vivo electromyography (EMG) recording, 3D printing carbon electrodes exhibit much higher signal-to-noise ratio (40.63 ± 7.73) than Pt electrodes (14.26 ± 6.83). The proposed biofabrication method is envisioned to enable 3D printing in many emerging applications in biomedical engineering and electronics.

KEYWORDS:

3D printing; Additive manufacturing; Carbon electrode; Fabrication

PMID:
29170867
DOI:
10.1007/s10544-017-0247-3
[Indexed for MEDLINE]
Icon for Springer
11.
Front Neuroanat. 2017 Nov 7;11:101. doi: 10.3389/fnana.2017.00101. eCollection 2017.

The Paravascular Pathway for Brain Waste Clearance: Current Understanding, Significance and Controversy.

Author information

1
School of Medicine, Wayne State University, Detroit, MI, United States.
2
Department of Radiology, The First Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou, China.
3
Department of Radiology, Wayne State University, Detroit, MI, United States.

Abstract

The paravascular pathway, also known as the "glymphatic" pathway, is a recently described system for waste clearance in the brain. According to this model, cerebrospinal fluid (CSF) enters the paravascular spaces surrounding penetrating arteries of the brain, mixes with interstitial fluid (ISF) and solutes in the parenchyma, and exits along paravascular spaces of draining veins. Studies have shown that metabolic waste products and solutes, including proteins involved in the pathogenesis of neurodegenerative diseases such as amyloid-beta, may be cleared by this pathway. Consequently, a growing body of research has begun to explore the association between glymphatic dysfunction and various disease states. However, significant controversy exists in the literature regarding both the direction of waste clearance as well as the anatomical space in which the waste-fluid mixture is contained. Some studies have found no evidence of interstitial solute clearance along the paravascular space of veins. Rather, they demonstrate a perivascular pathway in which waste is cleared from the brain along an anatomically distinct perivascular space in a direction opposite to that of paravascular flow. Although possible explanations have been offered, none have been able to fully reconcile the discrepancies in the literature, and many questions remain. Given the therapeutic potential that a comprehensive understanding of brain waste clearance pathways might offer, further research and clarification is highly warranted.

KEYWORDS:

amyloid-beta; brain waste clearance; glymphatic system; paravascular pathway; perivascular pathway

Publication type

Publication type

12.
Magn Reson Imaging. 2018 Apr;47:1-6. doi: 10.1016/j.mri.2017.11.005. Epub 2017 Nov 14.

An interleaved sequence for simultaneous magnetic resonance angiography (MRA), susceptibility weighted imaging (SWI) and quantitative susceptibility mapping (QSM).

Author information

1
Sino-Dutch Biomedical and Information Engineering School, Northeastern University, Shenyang, China; The MRI Institute for Biomedical Research, Detroit, MI, USA; Department of Radiology, School of Medicine, Wayne State University, Detroit, MI, USA.
2
The MRI Institute for Biomedical Research, Detroit, MI, USA.
3
The MRI Institute for Biomedical Research, Waterloo, Ontario, Canada.
4
The MRI Institute for Biomedical Research, Detroit, MI, USA; Department of Radiology, School of Medicine, Wayne State University, Detroit, MI, USA.
5
Sino-Dutch Biomedical and Information Engineering School, Northeastern University, Shenyang, China.
6
Sino-Dutch Biomedical and Information Engineering School, Northeastern University, Shenyang, China; The MRI Institute for Biomedical Research, Detroit, MI, USA; Department of Radiology, School of Medicine, Wayne State University, Detroit, MI, USA; The MRI Institute for Biomedical Research, Waterloo, Ontario, Canada. Electronic address: nmrimaging@aol.com.

Abstract

PURPOSE:

To image the entire vasculature of the brain with complete suppression of signal from background tissue using a single 3D excitation interleaved rephased/dephased multi-echo gradient echo sequence. This ensures no loss of signal from fast flow and provides co-registered susceptibility weighted images (SWI) and quantitative susceptibility maps (QSM) from the same scan.

MATERIALS AND METHODS:

The suppression of background tissue was accomplished by subtracting the flow-dephased images from the flow-rephased images with the same echo time of 12.5ms to generate a magnetic resonance angiogram and venogram (MRAV). Further, a 2.5ms flow-compensated echo was added in the rephased portion to provide sufficient signal for major arteries with fast flow. The QSM data from the rephased 12.5ms echo was used to suppress veins on the MRAV to generate an artery-only MRA. The proposed approach was tested on five healthy volunteers at 3T.

RESULTS:

This three-echo interleaved GRE sequence provided complete background suppression of stationary tissues, while the short echo data gave high signal in the internal carotid and middle cerebral arteries (MCA). The contrast-to-noise ratio (CNR) of the arteries was significantly improved in the M3 territory of the MCA compared to the non-linear subtraction MRA and TOF-MRA. Veins were suppressed successfully utilizing the QSM data.

CONCLUSION:

The background tissue can be properly suppressed using the proposed interleaved MRAV sequence. One can obtain whole brain MRAV, MRA, SWI, true-SWI (or tSWI) and QSM data simultaneously from a single scan.

KEYWORDS:

Magnetic resonance angiography (MRA); Magnetic resonance angiography and venography (MRAV); Quantitative susceptibility mapping (QSM); Susceptibility weighted imaging (SWI)

13.
Hear Res. 2017 Nov 14. pii: S0378-5955(17)30487-2. doi: 10.1016/j.heares.2017.10.017. [Epub ahead of print]

Glutamate is down-regulated and tinnitus loudness-levels decreased following rTMS over auditory cortex of the left hemisphere: A prospective randomized single-blinded sham-controlled cross-over study.

Author information

1
Department of Communication Sciences & Disorders, Wayne State University, Detroit, MI, USA. Electronic address: cacacea@wayne.edu.
2
Department of Radiology, Wayne State University School of Medicine, Detroit, MI, USA.
3
Department of Psychology, Union College, Schenectady, NY, USA.
4
Department of Rehabilitation Sciences, University at Buffalo, Buffalo, NY, USA.
5
Department of Otolaryngology - Head and Neck Surgery, University of Iowa, Iowa City, IA, USA; Department of Communication Sciences & Disorders, University of Iowa, Iowa City, IA, USA.

Abstract

Using a prospective randomized single-blinded sham-controlled cross-over design, we studied the efficacy of low frequency (1-Hz) repetitive transcranial magnetic stimulation (rTMS) over auditory cortex of the left temporal lobe as an experimental treatment modality for noise-induced tinnitus. Pre/post outcome measures for sham vs. active rTMS conditions included differential changes in tinnitus loudness, self-perceived changes in the Tinnitus Handicap Questionnaire (THQ), and neurochemical changes of brain metabolite concentrations using single voxel proton magnetic resonance spectroscopy (1H-MRS) obtained from left and right auditory cortical areas. While no subject in our sample had complete abatement of their tinnitus percept, active but not sham rTMS significantly reduced the loudness level of the tinnitus perception on the order of 4.5 dB; improved subscales in several content areas on the THQ, and down regulated (reduced) glutamate concentrations specific to the auditory cortex of the left temporal lobe that was stimulated. In addition, significant pair-wise correlations were observed among questionnaire variables, metabolite variables, questionnaire-metabolite variables, and metabolite-loudness variables. As part of this correlation analysis, we demonstrate for the first time that active rTMS produced a down regulation in the excitatory neurotransmitter glutamate that was highly correlated (r = 0.77, p < 0.05) with a reduction in tinnitus loudness levels measured psychoacoustically with a magnitude estimation procedure. Overall, this study provides unique information on neurochemical, psychoacoustic, and questionnaire-related profiles which emphasizes the emerging fields of perceptual and cognitive MRS and provides a perspective on a new frontier in auditory and tinnitus-related research.

KEYWORDS:

Loudness scaling; Magnetic resonance imaging; Magnetic resonance spectroscopy; Metabolites; Repetitive transcranial magnetic stimulation; Tinnitus

14.
Biomed Res Int. 2017;2017:2059036. doi: 10.1155/2017/2059036. Epub 2017 Sep 10.

Automatic Segmentation of Ultrasound Tomography Image.

Wu S1,2, Yu S1,2, Zhuang L3, Wei X4, Sak M3,5, Duric N3,5, Hu J6, Xie Y1.

Author information

1
Institute of Biomedical and Health Engineering, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, 1068 Xueyuan Avenue, Shenzhen University Town, Shenzhen 518055, China.
2
Shenzhen Colleges of Advanced Technology, University of Chinese Academy of Sciences, 1068 Xueyuan Avenue, Shenzhen University Town, Shenzhen 518055, China.
3
Department of Oncology, The Karmanos Cancer Institute, Wayne State University, Detroit, MI 48201, USA.
4
Department of Radiology, Guangzhou First Hospital, Guangzhou Medical University, Guangzhou 510180, China.
5
Delphinus Medical Technologies, Inc., Plymouth, MI 48170, USA.
6
Department of Radiology, Wayne State University, Detroit, MI 48201, USA.

Abstract

Ultrasound tomography (UST) image segmentation is fundamental in breast density estimation, medicine response analysis, and anatomical change quantification. Existing methods are time consuming and require massive manual interaction. To address these issues, an automatic algorithm based on GrabCut (AUGC) is proposed in this paper. The presented method designs automated GrabCut initialization for incomplete labeling and is sped up with multicore parallel programming. To verify performance, AUGC is applied to segment thirty-two in vivo UST volumetric images. The performance of AUGC is validated with breast overlapping metrics (Dice coefficient (D), Jaccard (J), and False positive (FP)) and time cost (TC). Furthermore, AUGC is compared to other methods, including Confidence Connected Region Growing (CCRG), watershed, and Active Contour based Curve Delineation (ACCD). Experimental results indicate that AUGC achieves the highest accuracy (D = 0.9275 and J = 0.8660 and FP = 0.0077) and takes on average about 4 seconds to process a volumetric image. It was said that AUGC benefits large-scale studies by using UST images for breast cancer screening and pathological quantification.

PMID:
29082240
PMCID:
PMC5610831
DOI:
10.1155/2017/2059036
[Indexed for MEDLINE]
Free PMC Article
Icon for Hindawi Publishing Corporation Icon for PubMed Central
15.
Am J Med Genet A. 2017 Dec;173(12):3153-3157. doi: 10.1002/ajmg.a.38497. Epub 2017 Oct 19.

Beyond Down syndrome phenotype: Paternally derived isodicentric chromosome 21 with partial monosomy 21q22.3.

Author information

1
Department of Obstetrics and Gynecology, Detroit Medical Center/Wayne State University, Detroit, Michigan.
2
Department of Obstetrics, Gynecology, and Reproductive Sciences, Magee-Womens Hospital, University of Pittsburgh, Pittsburgh, Pennsylvania.
3
Department of Pathology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania.
4
Department of Human Genetics, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, Pennsylvania.
5
Magee-Womens Research Institute, Pittsburgh, Pennsylvania.
6
Genescreen, Pittsburgh, Pennsylvania.

Abstract

Inverted isodicentric chromosome 21 is a rare form of chromosomal rearrangement that may result in trisomy 21; sometimes this rearrangement may also lead to segmental monosomy of the terminal long arm of chromosome 21. In this report, we describe the prenatal diagnosis and neonatal follow-up of a child with a paternally derived, de novo isodicentric chromosome 21 and a concurrent ∼1.2 Mb deletion of the 21q22.3 region [46,XX,idic(21)(q22.3)]. This child presented with unusual phenotype of Down syndrome and additional defects including esophageal atresia and tethered cord syndrome. The resulting phenotype in this infant might be a coalescence of the partial trisomy and monosomy 21, as well as homozygosity for idic (21). The utilization of chromosomal microarray in this case enabled accurate characterization of a rare chromosome abnormality, potentially contributes to future phenotype-genotype correlation and produced evidence for a molecular mechanism underlying this rearrangement.

KEYWORDS:

21q22.3 deletion; chromosomal microarray analysis (CMA); isodicentric 21; partial trisomy 21; prenatal diagnosis

PMID:
29048729
DOI:
10.1002/ajmg.a.38497
[Indexed for MEDLINE]
Icon for Wiley
16.
Retin Cases Brief Rep. 2017 Sep 27. doi: 10.1097/ICB.0000000000000636. [Epub ahead of print]

INDUCIBLE TRANSIENT CENTRAL RETINAL ARTERY VASOSPASM: A CASE REPORT.

Author information

1
Department of Ophthalmology, Kresge Eye Institute, Wayne State University, Detroit, Michigan.

Abstract

PURPOSE:

To report a case of inducible transient central retinal artery vasospasm with associated imaging.

METHODS:

Observational case report.

RESULTS:

A 51-year-old man presented for outpatient follow-up for recurrent inducible transient vision loss in his right eye. He experienced an episode during examination and was found to have central retinal artery vasospasm. Fundus photography and fluorescein angiography obtained during his vasospastic attack confirmed retinal arterial vasospasm. Treatment with a calcium-channel blocker (nifedipine) has been effective in preventing recurrent attacks.

CONCLUSION:

Idiopathic primary vasospasm is a rare cause of transient vision loss that is difficult to confirm because of the transient nature. We obtained imaging showing the initiation and resolution of the vasospastic event. The patient was then successfully treated with a calcium-channel blocker.

17.
Eur Radiol. 2018 Mar;28(3):992-999. doi: 10.1007/s00330-017-5051-1. Epub 2017 Sep 27.

Diffusion-weighted imaging in relation to morphology on dynamic contrast enhancement MRI: the diagnostic value of characterizing non-puerperal mastitis.

Author information

1
Department of Radiology, First Affiliated Hospital of Dalian Medical University, 222 Zhongshan Road, Xigang, Dalian, Liaoning, 116011, China.
2
Department of Radiology, Wayne State University, 540 East Canfield Street, Detroit, MI, 48201, USA.
3
Department of Radiology, Chengban Branch of West China Hospital, 37 Guoxue Alley, Wuhou, Chengdu, Sichuan, 610041, China.
4
Department of Radiology, First Affiliated Hospital of Dalian Medical University, 222 Zhongshan Road, Xigang, Dalian, Liaoning, 116011, China. alya211@163.com.
5
Department of Radiology, Second Affiliated Hospital of Dalian Medical University, 467 Zhongshan Road, Shahekou, Dalian, Liaoning, 116023, China. wsw_2003@163.com.

Abstract

OBJECTIVES:

To demonstrate the value of diffusion-weighted imaging (DWI) in the characterisation of mastitis lesions.

METHODS:

Sixty-one non-puerperal patients with pathologically confirmed single benign mastitis lesions underwent preoperative examinations with conventional MRI and axial DWI. Patients were categorised into three groups: (1) periductal mastitis (PDM), (2) granulomatous lobular mastitis (GLM), and (3) infectious abscess (IAB). Apparent diffusion coefficient (ADC) values of each lesion were recorded. A one-way ANOVA with logistic analysis was performed to compare ADC values and other parameters. Discriminative abilities of DWI modalities were compared using the area under the receiver operating characteristic curve (AUC). P < 0.05 was considered statistically significant.

RESULTS:

ADC values differed significantly among the three groups (P = 0.003) as well as between PDM and IAB and between PDM and GLM. The distribution of non-mass enhancement on dynamic contrast-enhanced (DCE) MRI differed significantly among the three groups (P = 0.03) but not between any two groups specifically. There were no differences in lesion location, patient age, T2WI or DWI signal intensity, enhancement type, non-mass internal enhancement, or mass enhancement characteristics among the three groups.

CONCLUSIONS:

ADC values and the distribution of non-mass enhancement are valuable in classifying mastitis subtypes.

KEY POINTS:

• Mastitis subtypes exhibit different characteristics on DWI and DCE MRI. • ADC values are helpful in isolating PDM from other mastitis lesions. • Distribution of non-mass enhancement also has value in comparing mastitis subtypes.

KEYWORDS:

abscess; diffusion magnetic resonance imaging; granulomatous mastitis; image enhancement; mastitis

PMID:
28956122
PMCID:
PMC5811586
DOI:
10.1007/s00330-017-5051-1
[Indexed for MEDLINE]
Free PMC Article
Icon for Springer Icon for PubMed Central
18.
Diabetes. 2017 Dec;66(12):3111-3121. doi: 10.2337/db16-1182. Epub 2017 Sep 12.

MicroRNA-146a Mimics Reduce the Peripheral Neuropathy in Type 2 Diabetic Mice.

Author information

1
Department of Neurology, Henry Ford Health System, Detroit, MI xsliu@neuro.hfh.edu.
2
Department of Neurology, Henry Ford Health System, Detroit, MI.
3
Sichuan Key Laboratory of Medical Imaging and Department of Microbiology and Immunology, North Sichuan Medical College, Nanchong, Sichuan, China.
4
Department of Radiology, Wayne State University, Detroit, MI.
5
Sichuan Key Laboratory of Medical Imaging and Department of Radiology, Affiliated Hospital of North Sichuan Medical College, Nanchong, Sichuan, China.
6
Department of Physics, Oakland University, Rochester, MI.

Abstract

MicroRNA-146a (miR-146a) regulates multiple immune diseases. However, the role of miR-146a in diabetic peripheral neuropathy (DPN) has not been investigated. We found that mice (db/db) with type 2 diabetes exhibited substantial downregulation of miR-146a in sciatic nerve tissue. Systemic administration of miR-146a mimics to diabetic mice elevated miR-146a levels in plasma and sciatic nerve tissue and substantially increased motor and sensory nerve conduction velocities by 29 and 11%, respectively, and regional blood flow by 50% in sciatic nerve tissue. Treatment with miR-146a mimics also considerably decreased the response in db/db mice to thermal stimuli thresholds. Histopathological analysis showed that miR-146a mimics markedly augmented the density of fluorescein isothiocyanate-dextran-perfused blood vessels and increased the number of intraepidermal nerve fibers, myelin thickness, and axonal diameters of sciatic nerves. In addition, miR-146a treatment reduced and increased classically and alternatively activated macrophage phenotype markers, respectively. Analysis of miRNA target array revealed that miR-146a mimics greatly suppressed expression of many proinflammatory genes and downstream related cytokines. Collectively, our data indicate that treatment of diabetic mice with miR-146a mimics robustly reduces DPN and that suppression of hyperglycemia-induced proinflammatory genes by miR-146a mimics may underlie its therapeutic effect.

PMID:
28899883
PMCID:
PMC5697943
[Available on 2018-12-01]
DOI:
10.2337/db16-1182
[Indexed for MEDLINE]
Free full text
Icon for HighWire
19.
Sensors (Basel). 2017 Aug 8;17(8). pii: E1827. doi: 10.3390/s17081827.

Efficient Segmentation of a Breast in B-Mode Ultrasound Tomography Using Three-Dimensional GrabCut (GC3D).

Yu S1,2, Wu S3,4, Zhuang L5, Wei X6, Sak M7,8, Neb D9,10, Hu J11, Xie Y12.

Author information

1
Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China. sd.yu@siat.ac.cn.
2
Shenzhen College of Advanced Technology, University of Chinese Academy of Sciences, Shenzhen 518055, China. sd.yu@siat.ac.cn.
3
Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China. sb.wu@siat.ac.cn.
4
Shenzhen College of Advanced Technology, University of Chinese Academy of Sciences, Shenzhen 518055, China. sb.wu@siat.ac.cn.
5
Department of Oncology, the Karmanos Cancer Institute, Wayne State University, Detroit, MI 48201, USA. zhuangling@gmail.com.
6
Department of Radiology, Guangzhou first Hospital, Guangzhou Medical University, Guangzhou 510180, China. weixinhua@aliyun.com.
7
Department of Oncology, the Karmanos Cancer Institute, Wayne State University, Detroit, MI 48201, USA. sakm@karmanos.org.
8
Delphinus Medical Technologies, Inc., Plymouth, Detroit, MI 46701, USA. sakm@karmanos.org.
9
Department of Oncology, the Karmanos Cancer Institute, Wayne State University, Detroit, MI 48201, USA. duric@karmanos.org.
10
Delphinus Medical Technologies, Inc., Plymouth, Detroit, MI 46701, USA. duric@karmanos.org.
11
Department of Radiology, Wayne State University, Detroit, MI 48201, USA. jhu@med.wayne.edu.
12
Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China. yq.xie@siat.ac.cn.

Abstract

As an emerging modality for whole breast imaging, ultrasound tomography (UST), has been adopted for diagnostic purposes. Efficient segmentation of an entire breast in UST images plays an important role in quantitative tissue analysis and cancer diagnosis, while major existing methods suffer from considerable time consumption and intensive user interaction. This paper explores three-dimensional GrabCut (GC3D) for breast isolation in thirty reflection (B-mode) UST volumetric images. The algorithm can be conveniently initialized by localizing points to form a polygon, which covers the potential breast region. Moreover, two other variations of GrabCut and an active contour method were compared. Algorithm performance was evaluated from volume overlap ratios ( T O , target overlap; M O , mean overlap; F P , false positive; F N , false negative) and time consumption. Experimental results indicate that GC3D considerably reduced the work load and achieved good performance ( T O = 0.84; M O = 0.91; F P = 0.006; F N = 0.16) within an average of 1.2 min per volume. Furthermore, GC3D is not only user friendly, but also robust to various inputs, suggesting its great potential to facilitate clinical applications during whole-breast UST imaging. In the near future, the implemented GC3D can be easily automated to tackle B-mode UST volumetric images acquired from the updated imaging system.

KEYWORDS:

image segmentation; ultrasound tomography; whole breast imaging

Conflict of interest statement

The authors declare no conflict of interest. The founding sponsors had no role in the design of the study; in the collection, analysis or interpretation of data; in the writing of the manuscript; nor in the decision to publish the results.

20.
BMC Cancer. 2017 Aug 7;17(1):525. doi: 10.1186/s12885-017-3518-8.

A pilot evaluation of magnetic resonance imaging characteristics seen with solid papillary carcinomas of the breast in 4 patients.

Author information

1
Department of Radiology, First Affiliated Hospital of Dalian Medical University, Dalian, 116011, China.
2
Department of Oncology, Wayne State University School of Medicine, Detroit, USA.
3
Department of Pathology, First Affiliated Hospital of Dalian Medical University, Dalian, China.
4
Department of Biomedical Engineering, Southern Medical University, Guangzhou, Guangdong, China.
5
Department of Radiology, First Affiliated Hospital of Dalian Medical University, Dalian, 116011, China. alya211@163.com.
6
Department of Radiology, Wayne State University, Detroit, USA. jhu@med.wayne.edu.

Abstract

BACKGROUND:

Solid papillary carcinoma (SPC) is a rare variant of breast papillary carcinoma with unique pathological morphology and biological behavior. There is only one case report on T1-MRI of SPC. In this study, we report our findings on this new category of papillary carcinoma to fill the gap in MRI characterization of SPC.

METHODS:

This retrospective study included four pathology-confirmed in situ SPC patients. Conventional MRI, diffusion weighted imaging (DWI), and magnetic resonance spectroscopy (MRS) were performed with a 1.5 T whole-body MR scanner before surgical operation. The following characteristics of each lesion were recorded: signal intensity on T2WI/STIR and T1FSPGR, morphology, maximum lesion size, and time intensity curve (TIC) on dynamic contrast enhancement MRI (DCE-MRI), apparent diffusion coefficient (ADC) value from DWI, and Cho peak from MRS.

RESULTS:

Signal intensities of all lesions were heterogenous on T2WI/STIR and T1FSPGR. Mass enhancements were observed for all lesions with either oval or irregular shapes on DCE-MRI. The maximum lesion size ranged from 0.8 cm to 3.2 cm. All lesion margins were circumscribed, and internal enhancements were homogeneous or heterogeneous from DCE-MRI. TIC appeared with a rapid increase in initial contrast phases of all lesions. All lesions on DWI (b = 1000s/mm2) were slightly hyperintense with an ADC value range of 1.3 × 10-3 mm2/s to 1.9 × 10-3 mm2/s. Cho peak was absent at 3.2 ppm for all lesions.

CONCLUSIONS:

MRI characteristics of SPC include heterogeneous signal intensity within the lesion on T2WI/STIR and T1FSPGR, mass enhancement with circumscribed margins, either oval or irregular shapes, and a rapid initial enhancement of TIC on DCE-MRI. ADC values and the absence of Cho peak may provide valuable information to distinguish SPC from other invasive breast carcinomas.

KEYWORDS:

Diffusion magnetic resonance imaging; Magnetic resonance imaging; Magnetic resonance spectroscopy; Solid papillary carcinoma

PMID:
28784112
PMCID:
PMC5547522
DOI:
10.1186/s12885-017-3518-8
[Indexed for MEDLINE]
Free PMC Article
Icon for BioMed Central Icon for PubMed Central

Supplemental Content

Loading ...
Support Center