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Zheng F, Tang D, Xu H, Xu Y, Dai W, Zhang X, Hong X, Liu D, Dai Y. Genomewide analysis of 6-methyladenine DNA in peripheral blood mononuclear cells of systemic lupus erythematosus. Lupus 2019; 28:359-364. [PMID: 30744524 DOI: 10.1177/0961203319828520] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Aim The aim of this paper is to explore the expression of 6-methyladenine (6mA) DNA and to elucidate its gene regulation role in systemic lupus erythematosus (SLE). Methods Twenty SLE patients and 20 normal control healthy individuals (HCs) were included in this study. Genomic DNA was isolated from peripheral blood mononuclear cells and subsequently underwent 6mA-immunoprecipitation-sequencing (6mA-IP-Seq) after DNA quality control and 6mA precipitation. Bioinformation analysis was applied to the raw data comparing 6mA levels between SLE patients and HCs. Results We identified 5462 hypermethylation and 431 hypomethylation genes in PBMCs of individuals with SLE, which indicated that a high level of 6mA participates in the pathogenesis of SLE. Gene ontology analysis revealed that hypermethylation genes might regulate the inflammatory process, which has been well documented in the pathogenesis of SLE. Conclusion 6mA may be involved in the initial development of SLE, which may lead to its potential use as an early diagnostic marker and therapeutic target.
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77
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Deng L, Huang X, Yang C, Lyu B, Duan F, Tang D, Song Y. Numerical simulation study on systolic anterior motion of the mitral valve in hypertrophic obstructive cardiomyopathy. Int J Cardiol 2019; 266:167-173. [PMID: 29887442 DOI: 10.1016/j.ijcard.2018.01.062] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/24/2017] [Revised: 12/11/2017] [Accepted: 01/15/2018] [Indexed: 12/01/2022]
Abstract
BACKGROUND The hydrodynamic mechanisms of systolic anterior motion (SAM) of the mitral valve in hypertrophic obstructive cardiomyopathy (HOCM) remain unclear. METHODS Based on computed tomography (CT) images and clinical data, pre- and post-operative computational models of the left ventricle were constructed for 6 HOCM patients receiving septal myectomy. SAM was abolished in 5 patients and persisted in one after septal myectomy surgery. The obtained simulation results including flow field of the left ventricle and mechanical behaviors of the mitral valve (MV) between pre- and post-operative FSI models were compared. RESULTS The pressure difference and shear stress on the mitral valve leaflets (MVL) were relatively high pre-operatively, and decreased significantly after satisfactory surgery, but remained high following failed surgery. The significant increase in coaptation-to-septal distance was found when SAM was abolished. CONCLUSIONS Our results indicated that high pressure difference and shear stress on the MVL might directly initiate SAM in HOCM. Successful septal myectomy enlarged the coaptation-to-septal distance sufficiently to keep the MVL away from the ejection flow, thereby eliminating SAM.
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78
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Li C, Baird C, Yao J, Yang C, Wang L, Yu H, Geva T, Tang D. Computational Modeling of Human Bicuspid Pulmonary Valve Dynamic Deformation in Patients with Tetralogy of Fallot. ACTA ACUST UNITED AC 2019. [DOI: 10.32604/cmes.2019.06036] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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79
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Tang D, Siu B. Maternal Infanticide and Filicide in a Psychiatric Custodial Institution in Hong Kong. East Asian Arch Psychiatry 2018; 28:139-143. [PMID: 30563951] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
OBJECTIVE The aim of this study was to review the history, legislation, and psychiatric perspective of filicide, to compare the characteristics of mothers who committed neonaticide versus infanticide, and to discuss the infanticide law in Hong Kong. METHODS Data of mothers remanded to the Siu Lam Psychiatric Centre from 2008 to 2016 for filicide were reviewed, as were data of filicide from the Child Fatality Review Reports published by the Social Welfare Department. RESULTS From 2008 to 2016, eight mothers were remanded to Siu Lam Psychiatric Centre for filicide. Four were convicted of infanticide; the other four were convicted of manslaughter. Those convicted of infanticide were single and aged <18 years. They had concealed their pregnancies and received no antenatal care. They delivered at home and then either smothered or abandoned the newborn. They reported no suicidal attempts after the index offence and had no record of mental illness. They were given supervision orders instead of prison sentences. In contrast, those convicted of manslaughter were in their 30s and married. They were documented to have killed the victims by charcoal burning, strangulation, mutilation, or defenestration. They all attempted suicide immediately after the killing and had histories of mental illness: paranoid schizophrenia (n = 2), severe depressive disorder with psychotic symptoms (n = 1), and recurrent depressive disorder (n = 1). They were sentenced to Hospital Orders for unspecified periods. CONCLUSIONS In Hong Kong, the incidence of maternal filicide is low. However, the infanticide provision grants leniency to mothers, including those who show no evidence of mental illness.
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Tao L, Zhou L, Wu HT, Li XM, Chen XL, Li C, Xie M, Zhang M, Cheng L, Tang D. [Retrospective analysis of 760 laryngeal squamous cell carcinoma patients treated with open laryngeal function-preserving operations]. LIN CHUANG ER BI YAN HOU TOU JING WAI KE ZA ZHI = JOURNAL OF CLINICAL OTORHINOLARYNGOLOGY, HEAD, AND NECK SURGERY 2018; 32:737-744. [PMID: 29873209 DOI: 10.13201/j.issn.1001-1781.2018.10.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 03/17/2018] [Indexed: 11/12/2022]
Abstract
Objective:To explore the fundamental clinical characteristics and survival prognostic factors of laryngeal squamous cell carcinoma (LSCC) patients treated with open laryngeal function-preserving operations. Method: The collected clinical data and the follow-up survival information from 760 patients with LSCC undergoing open laryngeal function-preserving operations between January 2005 and December 2010 in Eye & ENT Hospital of Fudan University were retrospectively analyzed. Kaplan-Meier was applied to calculate survival rates. Log-rank test and Cox regression model were performed to evaluate the survival prognostic factors for univariate and multivariate analysis. Result: Among the enrolled 760 cases, 697 patients were glottic cancer, followed by 59 cases in supraglottis and 4 cases in subglottis. The number of laryngeal cancer patients staged in T1 to T4 was 222, 420, 112 and 6, respectively. 27 patients had positive cervical lymph nodes. There were 220, 408, 111 and 21 patients with clinical stage Ⅰ to Ⅳ, respectively. The 5-year overall survival (OS), disease free survival (DFS) and disease specific survival (DSS) rates were 89.3%, 83.9% and 89.8%, respectively. Multivariate Cox analysis indicated that clinical stage and second primary tumor were independent influencing factors for the OS rate, while, age, primary site, pathological differentiation, T stage, clinical stage and surgical margin were independent risk factors for tumor recurrence and progression (P<0.05). Conclusion: Open laryngeal function-preserving operation is a crucial therapeutic strategy applicable to LSCC patients in early and selected advanced stage in China. Early diagnosis and therapy, and sufficient safety surgical margin are keys for improving the survival rate and reducing the risk of relapse for laryngeal cancer patients.
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81
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Nie J, Yan Z, Duan L, Wang X, Tang D, Niu Q. Involvment of ATM/Chk2-p53 signaling pathway in B[a]P-induced neural cell apoptosis. Toxicol Lett 2018. [DOI: 10.1016/j.toxlet.2018.06.857] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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82
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Wang T, Yan M, Tang D, Xue L, Zhang T, Dong Y, Zhu L, Wang X, Dong Y. A retrospective, multicenter study of voriconazole trough concentrations and safety in patients with Child-Pugh class C cirrhosis. J Clin Pharm Ther 2018; 43:849-854. [PMID: 29893015 DOI: 10.1111/jcpt.12724] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Accepted: 05/17/2018] [Indexed: 12/19/2022]
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83
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Han X, Wang X, Wang L, Zheng Z, Gu J, Tang D, Liu L, Liu S. Investigation of grey matter abnormalities in multiple sclerosis patients by combined use of double inversion recovery sequences and diffusion tensor MRI at 3.0 Tesla. Clin Radiol 2018; 73:834.e17-834.e23. [PMID: 29861163 DOI: 10.1016/j.crad.2018.04.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2017] [Accepted: 04/25/2018] [Indexed: 10/14/2022]
Abstract
AIM To investigate the grey matter abnormalities in multiple sclerosis (MS) patients by combined use of double inversion recovery (DIR) sequences and diffusion tensor (DTI) magnetic resonance imaging (MRI) at 3 T. MATERIALS AND METHODS Twenty relapsing-remitting MS (RRMS) patients and 20 healthy control were enrolled in this study. All participants underwent DIR and DTI MRI and completed the Mini-Mental State Examination (MMSE) and Expanded Disability Status Scale (EDSS). The cortical lesions and normal-appearing grey matter (NAGM) of the patient group, as well as the NAGM of the control group were quantitatively analysed using the DIR and DTI images. The average NAGM mean diffusion (MD) and fractional anisotropy (FA) values of the patient group and control group were measured and compared. The correlation between NAGM MD and FA values and the number of cortical lesions, cognitive impairment, as well as the degree of nerve damage were analysed. RESULTS The NAGM of the patient group had average MD and FA values that were significantly different compared with the control group. In addition, the NAGM FA values of the MS patients were negatively correlated with the MMSE score, but positively correlated with the EDSS score. The NAGM MD values of the MS patients were also negatively correlated with the MMSE score, but positively correlated with the EDSS score. CONCLUSIONS The NAGM of MS patients has microstructural damages. The extent of such damage was correlated with the number of cortical lesions. The severity of the damage also correlated with increased severity of cognitive impairment and neural defects.
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Hoffman AH, Teng Z, Zheng J, Wu Z, Woodard PK, Billiar KL, Wang L, Tang D. Stiffness Properties of Adventitia, Media, and Full Thickness Human Atherosclerotic Carotid Arteries in the Axial and Circumferential Directions. J Biomech Eng 2018; 139:2653366. [PMID: 28857112 DOI: 10.1115/1.4037794] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2017] [Indexed: 11/08/2022]
Abstract
Arteries can be considered as layered composite material. Experimental data on the stiffness of human atherosclerotic carotid arteries and their media and adventitia layers are very limited. This study used uniaxial tests to determine the stiffness (tangent modulus) of human carotid artery sections containing American Heart Association type II and III lesions. Axial and circumferential oriented adventitia, media, and full thickness specimens were prepared from six human carotid arteries (total tissue strips: 71). Each artery yielded 12 specimens with two specimens in each of the following six categories; axial full thickness, axial adventitia (AA), axial media (AM), circumferential full thickness, circumferential adventitia (CA), and circumferential media (CM). Uniaxial testing was performed using Inspec 2200 controlled by software developed using labview. The mean stiffness of the adventitia was 3570 ± 667 and 2960 ± 331 kPa in the axial and circumferential directions, respectively, while the corresponding values for the media were 1070 ± 186 and 1800 ± 384 kPa. The adventitia was significantly stiffer than the media in both the axial (p = 0.003) and circumferential (p = 0.010) directions. The stiffness of the full thickness specimens was nearly identical in the axial (1540 ± 186) and circumferential (1530 ± 389 kPa) directions. The differences in axial and circumferential stiffness of media and adventitia were not statistically significant.
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Tang D, Wang L, Maehara A, Molony D, Samady H, Wu Z, Zheng J, Mintz GS, Giddons DP. Abstract 646: A Simple Multi-Risk-Factor Decision-Making Strategy for Improved Coronary Plaque Burden Increase Prediction: a Patient-Specific 3D FSI Study Using IVUS Follow-up. Arterioscler Thromb Vasc Biol 2018. [DOI: 10.1161/atvb.38.suppl_1.646] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Plaque progression and vulnerability are influenced by many risk factors. Our goal is to find simple methods to combine multiple risk factors for better plaque development predictions.
A sample size of 374 intravascular ultrasound (IVUS) slices with matched follow-up was obtained from 9 patients (Mean age 59, 7 m) with informed consent obtained. 3D fluid-structure interaction models were constructed to obtain plaque stress/strain conditions. Four morphological and biomechanical factors (plaque burden (PB), cap thickness (CT), lipid percent (LP) and average plaque wall stress (PWS)) were chosen to predict plaque burden increase defined as
PBI = (PB at follow-up) - (PB at baseline).
For a given slice Si, the ground truth Y
PBI
is define as
Y
PBI
(Si)=1 if PBI(Si)>0; Y
PBI
=0 if PBI(Si)≤0.
For a single predictor W, a threshold value Wc was used to assign the binary prediction outcome:
Y
W
(Si)=1 if W>Wc; Y
W
(Si)=0 if W≤Wc.
Wc was chosen to get optimal agreement between Y
W
and Y
PBI
. To use multiple predictors (say, W1, W2, W3) to PBI, a new predictor Combo(W1,W2,W3) was created with its values defined as
Combo(W1,W2,W3)=Y
W1
+Y
W2
+Y
W3
, where Y
W1
, Y
W2
and Y
W3
were evaluated the same way as before. Combo was then treated as a single predictor and a threshold value was determined to achieve best agreement with Y
PBI
.
Table 1 summarizes the optimal thresholds and agreement rates for all 15 strategies. Agreement rate using PB alone was 57.5%. PWS was the best single predictor for PBI with agreement rate 62.6%. Combining CT and PWS achieved 66.5% agreement rate, 9% better over PB, which was also obtained by combining 4 risk factors.
The method presented here could be used to combine predictors from different sources (stenosis, cap, lipid, inflammation, macrophage, hemorrhage, stress, strain, flow shear stress, FFR, smoking, diabetes, cholesterol, alcohol, hypertension, pro-rupture genes, etc.) to improve prediction accuracy and help decision-making in clinical practice.
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Tang D, Wang Q, Canton G, Hatsukami TS, Billiar KL, Wu Z, Yuan C. Abstract 345: Combining Morphological and Mechanical Risk Factors May Improve Carotid Plaque Progression Prediction: an Magnetic Resonance Image-Based Follow-Up Study. Arterioscler Thromb Vasc Biol 2018. [DOI: 10.1161/atvb.38.suppl_1.345] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
It has been hypothesized that combining morphological and mechanical risk factors may improve plaque progression prediction. In this paper, plaque burden (PB), cap thickness (CT), lipid percent (LP), plaque wall stress (PWS), plaque wall strain (PWSn) and their combinations were used as predictors to identify the best predictor(s) for plaque progression measured by plaque area increase (PAI) from baseline (T1) and follow-up (T2).
In vivo magnetic resonance image (MRI) carotid plaque data were acquired from 8 patients (5 m, mean age 71) with follow-up (18 months) with informed consent obtained. We built 3D thin-layer models for the 41 matched slices to obtain plaque stress/strain data using patient-specific material properties determined from Cine MRI and patient arm blood pressure. The mean values of the 5 predictors from all lumen points of each slice were obtained for analysis. For each predictor Y, a threshold value Yc was determined so that optimal agreement rate was obtained (agreement cases are either {(Y>Yc) and (PAI >0)} or {(Y≤Yc) and (PAI ≤0)}). For PWS and PWSn, we used (either {(Y<Yc) and (PAI >0)} or {(Y≥Yc) and (PAI ≤0)}). Two combinations of predictors
COM1=a1*PB+a2*CT+a3*LP,
COM2=b1*PB+b2*CT+b3*LP+b4*PWS+b5*PWSn
were considered, where COM1 combines PB with morphological features, and COM2 combines all 5 predictors. The coefficients in these formulas were determined by using iterative linearly fitting method and initial guess of threshold values from single predictor results.
The optimal threshold values for the 5 single predictors and 2 combination predictors are given in Table 1. PWSn was the best single predictor and COM2 was the best combination predictor.
The threshold value-based method is simple and easy for clinical implementation. Our preliminary results indicate that combining PB, CT, LP, PWS, and PWSn could improve the agreement rate by nearly 10%, compared to using PB alone. Large-scale patient studies are needed to confirm our findings.
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Lee ACW, Fung HS, Poon WL, Chan PCM, Leung MWY, Liu CSW, Luk D, Cheung WY, Yuen KL, Tang D, Kwok PC, Tang KW. Percutaneous Sclerotherapy for Low-flow Vascular Malformations in Paediatric Patients: 6-Year Experience of a Multidisciplinary Team. HONG KONG JOURNAL OF RADIOLOGY 2018. [DOI: 10.12809/hkjr1616441] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
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Deng L, Huang X, Yang C, Song Y, Tang D. Patient-specific CT-based 3D passive FSI model for left ventricle in hypertrophic obstructive cardiomyopathy. Comput Methods Biomech Biomed Engin 2018; 21:255-263. [PMID: 29466869 DOI: 10.1080/10255842.2018.1443215] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Left ventricular outflow tract obstruction is observed in 70% of patients with hypertrophic cardiomyopathy, which occurs in about 1 of every 500 adults in the general population. It has been widely believed that the motion of the mitral valve, in particular, its systolic anterior motion (SAM), attributes significantly to such obstruction. For a better understanding of the mitral valve motion, a 3D patient-specific fluid-structure interaction model of the left ventricle from a patient with hypertrophic obstructive cardiomyopathy based on computed tomography (CT) scan images was proposed in this study. Displacement, structural stress, pressure, flow velocity and shear stress within the left ventricle and mitral valve were extracted to characterize their behavior. The maximum shear stress on mitral valve was 9.68 [Formula: see text]. The pressure on its posterior leaflet was higher than that on the anterior leaflet and the peak pressure on the mitral valve was 93.5 mm Hg which occurred at pre-SAM time. High angles of attack (54.3 ± 22.4°) were found in this patient. The methodology established in this study may have the potential to clarify the mechanisms of SAM and ultimately optimize surgical planning by comparing the mechanical results obtained from preoperative and postoperative models.
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89
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Muthiah S, Tang D, Nasr B, Verykiou S. A new era in holistic care: bridging the gap between dermatologists and oncologists for the treatment of malignant melanoma. Br J Dermatol 2018; 178:1-4. [PMID: 29357596 DOI: 10.1111/bjd.15385] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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90
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Wang L, Tang D, Maehara A, Wu Z, Yang C, Muccigrosso D, Zheng J, Bach R, Billiar KL, Mintz GS. Fluid-structure interaction models based on patient-specific IVUS at baseline and follow-up for prediction of coronary plaque progression by morphological and biomechanical factors: A preliminary study. J Biomech 2017; 68:43-50. [PMID: 29274686 DOI: 10.1016/j.jbiomech.2017.12.007] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2017] [Revised: 12/06/2017] [Accepted: 12/07/2017] [Indexed: 11/26/2022]
Abstract
Plaque morphology and biomechanics are believed to be closely associated with plaque progression. In this paper, we test the hypothesis that integrating morphological and biomechanical risk factors would result in better predictive power for plaque progression prediction. A sample size of 374 intravascular ultrasound (IVUS) slices was obtained from 9 patients with IVUS follow-up data. 3D fluid-structure interaction models were constructed to obtain both structural stress/strain and fluid biomechanical conditions. Data for eight morphological and biomechanical risk factors were extracted for each slice. Plaque area increase (PAI) and wall thickness increase (WTI) were chosen as two measures for plaque progression. Progression measure and risk factors were fed to generalized linear mixed models and linear mixed-effect models to perform prediction and correlation analysis, respectively. All combinations of eight risk factors were exhausted to identify the optimal predictor(s) with highest prediction accuracy defined as sum of sensitivity and specificity. When using a single risk factor, plaque wall stress (PWS) at baseline was the best predictor for plaque progression (PAI and WTI). The optimal predictor among all possible combinations for PAI was PWS + PWSn + Lipid percent + Min cap thickness + Plaque Area (PA) + Plaque Burden (PB) (prediction accuracy = 1.5928) while Wall Thickness (WT) + Plaque Wall Strain (PWSn) + Plaque Area (PA) was the best for WTI (1.2589). This indicated that PAI was a more predictable measure than WTI. The combination including both morphological and biomechanical parameters had improved prediction accuracy, compared to predictions using only morphological features.
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Wang L, Zhu J, Samady H, Monoly D, Zheng J, Guo X, Maehara A, Yang C, Ma G, Mintz GS, Tang D. Effects of Residual Stress, Axial Stretch, and Circumferential Shrinkage on Coronary Plaque Stress and Strain Calculations: A Modeling Study Using IVUS-Based Near-Idealized Geometries. J Biomech Eng 2017; 139:2580756. [PMID: 27814429 DOI: 10.1115/1.4034867] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2016] [Indexed: 11/08/2022]
Abstract
Accurate stress and strain calculations are important for plaque progression and vulnerability assessment. Models based on in vivo data often need to form geometries with zero-stress/strain conditions. The goal of this paper is to use IVUS-based near-idealized geometries and introduce a three-step model construction process to include residual stress, axial shrinkage, and circumferential shrinkage and investigate their impacts on stress and strain calculations. In Vivo intravascular ultrasound (IVUS) data of human coronary were acquired for model construction. In Vivo IVUS movie data were acquired and used to determine patient-specific material parameter values. A three-step modeling procedure was used to make our model: (a) wrap the zero-stress vessel sector to obtain the residual stress; (b) stretch the vessel axially to its length in vivo; and (c) pressurize the vessel to recover its in vivo geometry. Eight models were constructed for our investigation. Wrapping led to reduced lumen and cap stress and increased out boundary stress. The model with axial stretch, circumferential shrink, but no wrapping overestimated lumen and cap stress by 182% and 448%, respectively. The model with wrapping, circumferential shrink, but no axial stretch predicted average lumen stress and cap stress as 0.76 kPa and -15 kPa. The same model with 10% axial stretch had 42.53 kPa lumen stress and 29.0 kPa cap stress, respectively. Skipping circumferential shrinkage leads to overexpansion of the vessel and incorrect stress/strain calculations. Vessel stiffness increase (100%) leads to 75% lumen stress increase and 102% cap stress increase.
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92
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Wang WY, Chen Y, Su X, Tang D, Ben QW, Yao WY, Chen P, Yuan YZ. Resistin-Like Molecule-α Causes Lung Injury in Rats with Acute Pancreatitis by Activating the PI-3K/Akt-NF-κB Pathway and Promoting Inflammatory Cytokine Release. Curr Mol Med 2017; 16:677-687. [PMID: 27492801 DOI: 10.2174/1566524016666160802145700] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2016] [Revised: 07/18/2016] [Accepted: 07/19/2016] [Indexed: 11/22/2022]
Abstract
BACKGROUND Resistin-like molecule-α (RELMα) has diverse regulatory functions in inflammation, but its role in severe acute pancreatitis (SAP) and acute pancreatitis associated lung injury (APALI) remains unclear. METHODS SAP was induced in rats. RELMα protein expression was detected in lung tissue of rats to determine the relationship between APALI and RELMα. To investigate the effect of RELMα overexpression or knockdown on APALI, rats were given an intravenous injection of adenovirus vector before SAP induction. Lung and pancreatic samples were harvested 16 h after induction. After detection of RELMα protein levels, the severity of pancreatic and pulmonary injury was scored histologically, and serum and tissue levels of inflammatory mediators were measured. TUNEL assay and immunofluorescence were used to estimate pulmonary apoptosis and endothelial barrier integrity in lung tissue of SAP rats with RELMα knockdown. RESULTS RELMα expression was significantly up-regulated in APALI and was related to the lung injury index. RELMα overexpression aggravated the release of inflammatory cytokines including interleukin (IL)-1β, IL-6, IL-8, tumor necrosis factor-α, and serum C-reaction protein; the expression of inflammatory mediators phosphorylated (p)-AKT, p-P65, p-P38 mitogen activated protein kinase, p-extracellular regulated kinase, and intracellular adhesion molecule-1; and lung injury. RELMα knockdown had opposite effects. In addition, RELMα knockdown improved expression of proliferative cellular nuclear antigen, Bcl-2, zonal occluding-1 and Claudin-1 in lung tissue of SAP rats. CONCLUSION RELMα is associated with lung injury severity in SAP. RELMα augments inflammatory activity by increasing inflammatory cytokine release.
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Yuan Z, Naghavi A, Tang D, Kim Y, Ahmed K, Dhillon J, Giuliano A, Spiess P, Johnstone P. HPV/p16 Positivity and Nodal Status are Associated With Locoregional Control in Penile Cancer. Int J Radiat Oncol Biol Phys 2017. [DOI: 10.1016/j.ijrobp.2017.06.1269] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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94
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Wang B, Nie B, Tang D, Li R, Liu X, Song J, Wang W, Liu Z. Analysis of Meiotic Segregation Patterns and Interchromosomal Effects in Sperm from 13 Robertsonian Translocations. Balkan J Med Genet 2017; 20:43-50. [PMID: 28924540 PMCID: PMC5596821 DOI: 10.1515/bjmg-2017-0003] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
The frequency of the Robertonian (ROB) translocation in newborn babies is approximately one in 1000. Robertsonian translocation is an unusual type of chromosome rearrangement caused by two particular chromosomes joining together. The aim of the study was to analyze the segregation of the ROB translocations in 13 male carriers, and to verify a possible inter-chromosomal effect (ICE) of the ROB translocation on chromosomes 18, X, and Y. Thirteen male patients were included in the study. Multicolor fluorescent in situ hybridization (FISH) was used to analyze chromosomes 13, 14, 15, 21, 22, 18, X and Y in sperm. Among the heterozygous ROB translocation carriers, the frequency of normal/balanced spermatozoa resulting from alternate segregation varied between 70.4 and 85.2%. The frequency of unbalanced spermatozoa resulting from adjacent segregation varied between 14.8 and 29.6%. Increased frequencies of aneuploidy for a sex chromosome were found in 10 ROB translocation carriers (P2-P8, P10-P12). Increased frequencies of aneuploidy for chromosome 18 were found in10 ROB translocation carriers (P3-P9, P11-P13). In addition, increased frequencies of diploid were found in 11 ROB translocation carriers (P2-P9, P11-P13). Among the homozygous ROB translocation carriers, the rate of balanced spermatozoa was 99.7% and the frequency of unbalanced spermatozoa was 0.3%. However, the frequencies of aneuploidy for a sex chromosome and chromosome 18 were normal. Despite the high number of normal/balanced frequencies, there remained many unbalanced spermatozoa resulting from alternate segregation. The ROB translocation carriers may be at an increased risk for ICE. Robertsonian translocation homozygosity could be seen as a potential speciation in humans with 44 chromosomes.
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Guo X, Monoly D, Yang C, Samady H, Zheng J, Wang L, Mintz GS, Maehara A, Pei X, Li ZY, Tang D, Giddens DP. Abstract 383: Patient-Specific Coronary Models Combining Intravascular Ultrasound and Optical Coherence Tomography Lead to More Accurate Plaque Cap Thickness and Stress/Strain Quantifications. Arterioscler Thromb Vasc Biol 2017. [DOI: 10.1161/atvb.37.suppl_1.383] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Accurate cap thickness and stress/strain quantifications are of fundamental importance for vulnerable plaque research. An innovative modeling approach combining intravascular ultrasound (IVUS) and optical coherence tomography (OCT) is introduced for more accurate patient-specific coronary morphology and stress/strain calculations.
In vivo IVUS and OCT coronary plaque data were acquired from two patients with informed consent obtained. IVUS and OCT images were segmented, co-registered, and merged to form the IVUS+OCT data set, with OCT providing accurate cap thickness. Biplane angiography provided 3D vessel curvature. Due to IVUS resolution (150 μm), original virtual histology (VH) IVUS data often had lipid core exposed to lumen since it sets cap thickness as zero when cap thickness <150 μm. VH-IVUS data were processed with minimum cap thickness set as 50 and 180 μm to generate IVUS50 and IVUS180 data sets for modeling use. 3D fluid-structure interaction models based on IVUS+OCT, IVUS50 and IVUS180 data sets were constructed to investigate the impact of OCT cap thickness improvement on stress/strain calculations.
Figure 1 is a brief summary of results from 27 slices with cap covering lipid cores from 2 patients. Mean cap thickness (unit: mm) from Patient 1 was 0.353 (OCT), 0.201 (IVUS50), and 0.329 (IVUS180), respectively. Patient 2 mean cap thickness was 0.320 (OCT), 0.224 (IVUS50), and 0.285 (IVUS180). IVUS50 underestimated cap thickness (27 slices) by 34.5%, compared to OCT cap values. IVUS50 overestimated mean cap stress (27 slices) by 45.8%, compared to OCT cap stress (96.4 vs. 66.1 kPa). IVUS50 maximum cap stress was 59.2% higher than that from IVUS+OCT model (564.2 vs. 354.5 kPa). Differences between IVUS and IVUS+OCT models for mean cap strain and flow shear stress were modest (cap strain: <12%; FSS <2%).
Conclusion:
IVUS+OCT data and models could provide more accurate cap thickness and stress/strain calculations which will serve as basis for plaque research.
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Wang Q, Tang D, Canton G, Guo J, Guo X, Hatsukami TS, Billiar KL, Wu Z, Yuan C. Abstract 562: Human Carotid Atherosclerosis Plaque Progression and Vessel Material Stiffness at Follow Up Had Positive Correlation: An in vivo Vessel Stiffness MRI Follow Up Study. Arterioscler Thromb Vasc Biol 2017. [DOI: 10.1161/atvb.37.suppl_1.562] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
It is hypothesized that artery stiffness may be associated with plaque progression. However, in vivo vessel material stiffness follow-up data is lacking in the literature.
In vivo 3D multi-contrast and Cine magnetic resonance imaging (MRI) carotid plaque data were acquired from 8 patients with follow-up (18 months) with written informed consent obtained. Cine MRI and 3D thin-layer models were used to determine parameter values of the Mooney-Rivlin models for the 81slices from 16 plaques (2 scans/patient) using our established iterative procedures. Effective Young’s Modulus (YM) values for stretch ratio [1.0,1.3] were calculated for each slice for analysis.
Stress-stretch ratio curves from Mooney-Rivlin models for the 16 plaques and 81 slices are given in Fig. 1. Average YM value of the 81 slices was 411kPa. Slice YM values varied from 70 kPa (softest) to 1284 kPa (stiffest), a 1734% difference. Average slice YM values by vessel varied from 109 kPa (softest) to 922 kPa (stiffest), a 746% difference. Location-wise, the maximum slice YM variation rate within a vessel was 306% (139 kPa vs. 564 kPa). Average slice YM variation rate within a vessel for the 16 vessels was 134%. Average variation of YM values from baseline (T1) to follow up (T2) for all patients was 61.0%. The range of the variation of YM values was [-28.4%, 215%]. For progression study, YM increase (YMI=YM
T2
-TM
T1
) showed negative correlation with plaque progression measured by wall thickness increase (WTI), (r= -0.6802, p=0.0634). YM
T2
showed strong negative correlation with WTI (r= -0.7764, p=0.0235). Correlation between YM
T1
and WTI was not significant (r= -0.4353, p= 0.2811).
Conclusion
In vivo carotid vessel material properties have large variations from patient to patient, along the vessel segment within a patient, and from baseline to follow up. Use of patient-specific, location specific and time-specific material properties could potentially improve the accuracy of model stress/strain calculations.
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Wang ZC, Yuan Q, Zhu HW, Shen BS, Tang D. Computational Modeling for Fluid–Structure Interaction of Bioprosthetic Heart Valve with Different Suture Density: Comparison with Dynamic Structure Simulation. INT J PATTERN RECOGN 2017. [DOI: 10.1142/s0218001417570075] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
In this paper, a parametric geometry model based on elliptic and conic surfaces was developed for bioprosthetic heart valve (BHV) simulation. The valve material was modeled by a hyperelastic nonlinear anisotropic solid model. Different suture densities could be substituted by various bonded points between artery vessel and the leaflets as boundary conditions in the computational modeling. Besides these two assumptions that dynamic structure (DS) and fluid–structure interaction (FSI) both shared, the latter need incompressible viscous Newton fluid model to depict bloodstream passing through the BHV. Immersed boundary (IB) method was introduced to solve the FSI simulation. In addition, the DS analysis applied transvalvular pressure on the valve while FSI had left ventricular pressure on fluid inlet as initials. There was inconsistency between the moments of the maximum deformation and the maximum loading in both simulations. Although a similar trend of deformation lagging the load was viewed, the extent of delay in FSI was much smaller compared with that in DS simulation. The deformed profiles in cross-sectional views were shown in one picture to illustrate different dynamic responses caused by distinct assumptions. Percent of open area at the moments when the maximum deformation occurred was defined to show which calculation achieved better approximation for precise hemodynamics. Fixed point was given as boundaries between BHV and artery in the modeling part. Calculations showed that the more the fixed points in this bonded contact, the lower the principal stress was. The maximum shear stress showed a different trend. It had a different trend. Stress concentration in the conjunction area made it high-risk to be teared. Different suture densities had significant impaction in FSI simulations. With that analysis our work achieved a more comprehensive simulation to describe true hemodynamics of a BHV implanted in artery. The artery vessel had particular dynamic response under such assumptions, gradient existed in the maximum principal stress distribution diagram, from inner wall through which blood passing to the outer wall. Results showed a large suture density was suggested in BHV implantation.
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Anderson M, Morris L, Tang D, Batsides G, Kirtane A, Hanson I, Meraj P, Kapur N, O'Neill W. Impella RP Post Approval Study: First Multi-Center, Prospective Post Market Approval Results for the Impella RP in Patients with Right Ventricular Failure. J Heart Lung Transplant 2017. [DOI: 10.1016/j.healun.2017.01.158] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
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99
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Sawey E, Owens J, Cooke R, Kasirajan V, Markley R, Rao K, Smallfield M, Tang D, Tchoukina I, Shah K. Echocardiographic and Hemodynamic Characteristics of Total Artificial Heart Recipients. J Heart Lung Transplant 2017. [DOI: 10.1016/j.healun.2017.01.695] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
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100
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Zhang C, Peng Y, Li S, Zhou P, Munoz A, Tang D, Zhang Y. Spatial characterization of innervation zones under electrically elicited M-wave. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2017; 2016:121-124. [PMID: 28268294 DOI: 10.1109/embc.2016.7590655] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The three dimensional (3D) innervation zone (IZ) imaging approach (3DIZI) has been developed in our group to localize the IZ of a particular motor unit (MU) from its motor unit action potentials decomposed from high-density surface electromyography (EMG) recordings. In this study, the developed 3DIZI approach was combined with electrical stimulation to investigate global distributions of IZs in muscles from electrically elicited M-wave recordings. Electrical stimulations were applied to the musculocutaneous nerve to activate supramaximal muscle response of the biceps brachii in one healthy subject, and high-density (128 channels) surface EMG signals of the biceps brachii muscles were recorded. The 3DIZI approach was then employed to image the IZ distribution of IZs in the 3D space of the biceps brachii. The performance of the M-wave based 3DIZI approach was evaluated with different stimulation intensities. Results show that the reconstructed IZs under supramaximal stimulation are spatially distributed in the center region of muscle belly which is consistent with previous studies. With sub-maximal stimulation intensity, the imaged IZ centers became more proximally and deeply located. The proposed M-wave based 3DIZI approach demonstrated its capability of imaging global distribution of IZs in muscles, which provide valuable information for clinical applications such as guiding botulinum toxin injection in treating muscle spasticity.
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