Optimizing the Imaging Protocol for Ex Vivo Coronary Artery Wall Using High-Resolution MRI: An Experimental Study on Porcine and Human

Jiong Yang,Tao Li,Xiaoming Cui,Weihua Zhou,Xin Li,Xinwu Zhang 대한영상의학회 2013 Korean Journal of Radiology Vol.14 No.4

Objective: To optimize the MR imaging protocol for coronary arterial wall depiction in vitro and characterize the coronary atherosclerotic plaques. Materials and Methods: MRI examination was prospectively performed in ten porcine hearts in order to optimize the MR imaging protocol. Various surface coils were used for coronary arterial wall imaging with the same parameters. Then, the image parameters were further optimized for high-resolution coronary wall imaging. The signal-noise ratio (SNR) and contrast-noise ratio (CNR) of images were measured. Finally, 8 human cadaver hearts with coronary atherosclerotic plaques were prospectively performed with MRI examination using optimized protocol in order to characterize the coronary atherosclerotic plaques. Results: The SNR and CNR of MR image with temporomandibular coil were the highest of various surface coils. High-resolution and high SNR and CNR for ex vivo coronary artery wall depiction can be achieved using temporomandibular coil with 512 x 512 in matrix. Compared with histopathology, the sensitivity and specificity of MRI for identifying advanced plaques were: type IV-V (lipid, necrosis, fibrosis), 94% and 95%; type VI (hemorrhage), 100% and 98%; type VII (calcification), 91% and 100%; and type VIII (fibrosis without lipid core), 100% and 98%, respectively. Conclusion: Temporomandibular coil appears to be dramatically superior to eight-channel head coil and knee coil for ex vivo coronary artery wall imaging, providing higher spatial resolution and improved the SNR. Ex vivo high-resolution MRI has capability to distinguish human coronary atherosclerotic plaque compositions and accurately classify advanced plaques.

Risk Factors for Surgical Site Infections after Liver Resec-tion (A Multivariate Analysis of 6,132 Patients)

( Li-yang Sun ),( Jiong-jie Yu ),( Ju-dong Li ),( Xin-fei Xu ),( Jia-he Wang ),( Bing Quan ),( Wen-tao Yan ),( Feng Shen ),( Chao Li ),( Lei Liang ),( Tian Yang ) 대한간학회 2018 춘·추계 학술대회 (KASL) Vol.2018 No.1

Aims: Surgical site infection (SSI) is a common postoperative complication and associated with an increased morbidity, hospital stay, and overall cost. The aim of the present study was to identify risk factors for SSIs after hepatic resection based on a large single-center cohort. Methods: A retrospective study was conducted of 6,132 patients who underwent liver resection without concomitant biliary reconstruction or gastrointestinal procedures between 2014 and 2016 at the largest hepatic center in China. The occurrences of SSI, classified as incisional SSI and organ/space SSI within 30 days after operation were investigated. Patient- and surgical-related risk variables were collected using standardized data collection form. A likelihood ratio forward regression model was used to assess the independent association of risk factors with SSI. Results: SSI developed in 587 patients (9.6%), including superficial/deep incisional SSI in 357 patients (5.8 %), and organ/ space SSI in 304 patients (5.0 %). Multivariate logistic regression analysis showed that obesity, diabetes mellitus, ASA score ≥ 2, liver cirrhosis, re-hepatectomy, hepatoliathiasis, and intraoperative blood transfusion were independent risk factors of overall SSI. However, incisional and organ/space SSI differed from each other with respect to risk factors. Among a variety of risk factors, hepatolithiasis, liver cirrhosis, and intraoperative blood transfusion were consistently associated with both incisional and organ/space SSI. Conclusions: SSI is a common complication after liver resection, and more caution should be taken in patients with hepatolithiasis or liver cirrhosis. Prevention strategies focusing on factors associated with SSI is necessary in order to reduce SSI after liver resection.

Micromechanical investigation of thermal stresses of a finite plane containing multiple elliptical inclusions based on the equivalent inclusion method and distributed dislocation method

Jiong Zhang,Yunhai Huang,Weidong Liu,Liankun Wang,Chao Yang,Lin Zuo 대한기계학회 2021 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.35 No.1

This paper presents a micromechanical method to analyze the thermal stresses in a finite plane containing multiple elliptical inclusions. Firstly, the Eshelby’s equivalent inclusion method is employed to solve the elastic fields of a two-dimensional infinite plane containing multiple elliptical inclusions under a uniform temperature change. Both the interior Eshelby’s tensor and the exterior Eshelby’s tensor are employed. Then the boundary of the plane is modeled by continuous distributions of dislocation densities. By combining the two steps, a system of singular integral equations is formulated based on the traction-free boundary condition. Then the thermal stresses of the plane can be obtained by the superposition of the stresses obtained by the Eshelby’s equivalent inclusion method and distributed dislocation method. Additionally, some examples are given to show the effects of the presented method. The effects of the material constants, geometric parameters and fiber packing arrangement on the thermal stresses are also studied.

Stress-strain relationship for recycled aggregate concrete after exposure to elevated temperatures

Jiong-Feng Liang,Ze-Ping Yang,Ping-Hua Yi,Jian-Bao Wang 사단법인 한국계산역학회 2017 Computers and Concrete, An International Journal Vol.19 No.6

In this paper, the effects of elevated temperatures on the strength and compressive stress-strain curve (SSC) of recycled coarse aggregate concrete with different replacement percentages are presented. 90 recycled coarse aggregate concrete prisms are heated up to 20, 200, 400, 600, 800°C. The results show that the compressive strength, split tensile strength, elastic modulus of recycled aggregate concrete specimens decline significantly as the temperature rise. While the peak strain increase of recycled aggregate concrete specimens as the temperature rise. Compared to the experimental curves, the proposed stress-strain relations for recycled aggregate concrete after exposure elevated temperatures can be used in practical engineering applications.

Preparation of High-purity 1,3-Diacylglycerol Using Performanceenhanced Lipase Immobilized on Nanosized Magnetite Particles

Jiong-feng Zhao,Tao-Wang,Jianping Lin,Lirong Yang,Mian-bin Wu 한국생물공학회 2019 Biotechnology and Bioprocess Engineering Vol.24 No.2

Early research on the nutritional value of 1,3- diacylglycerols (1,3-DAGs) has resulted in a significant interest in their synthesis. 1,3-DAGs can be produced chemically and biologically. In this work, a regioselective lipase from Rhizopus oryzae was efficiently immobilized on nanosized magnetite particles (NSM) in an oriented way, resulting in significant enhancement of activity. The specific hydrolytic and esterification activities of the immobilized enzyme were 1,660% and 260% of those of the free enzyme, respectively. The immobilized enzyme was then used to catalyze the esterification of oleic acid with glycerol in a solvent-free system for preparation of 1,3-DAG in a 1 L reactor. The catalytic process was studied in detail, the final concentration of 1,3-DAG reached >76% under the optimal condition when the molar ratio of oleic acid to glycerol was 2.8:1. The regioselectivities of free and immobilized enzyme were both >97%. The immobilized enzyme was reused for 55 cycles with only ~30% activity loss at 30ºC. The purity of 1,3-DAG was up to ~95% (w/w) after a simple purification step with the recovery ratio ~85%. This is the first report of efficient 1,3-DAG purification by neutralization without acyl migration.

Flexural behavior of partially prefabricated partially encased composite beams

Jiong-feng Liang,Liu-feng Zhang,Ying-hua Yang,Li Wei 국제구조공학회 2021 Steel and Composite Structures, An International J Vol.38 No.6

An innovative partially precast partially encased composite beam (PPECB) is put forward based on the existing research. In order to study the flexural performance of the new composite beam which has precast part and cast-in-place part, six prefabricated specimens and one cast-in-place specimen are designed with considering the influence of the production method, the steel flange thickness, the concrete strength grade and the stirrup process on the behavior of the composite beam. Through four points loading and test data collection and analysis, the behavior of partially prefabricated specimen is similar to that of cast-in-place specimen, and the casting method, the thickness of the steel flange, the concrete strength grade and the stirrup process have different influence on the crack, yield and peak load bearing capacity of the component. Finally, the calculation theory of plastic bending of partially precast partially encased concrete composite beams is given. The calculation results are in good agreement with the experimental results, which can be used for practical engineering theory guidance. This paper can provide reference value for further research and engineering application.

Mechanical properties of recycled fine glass aggregate concrete under uniaxial loading

Jiong-Feng Liang,Ze-Ping Yang,Ping-Hua Yi,Jian-Bao Wang 사단법인 한국계산역학회 2015 Computers and Concrete, An International Journal Vol.16 No.2

This paper reports the results of an experimental study on the compressive strength and the stress-strain curve (SSC) of recycled fine glass aggregate concrete with different replacement percentages of recycled fine glass aggregate. The results show that the recycled fine glass aggregate contents have significant impact on the workability, compressive strength, the elastic modulus, the peak and the ultimate strains of recycled fine glass aggregate concrete. Analytical expressions for the stress–strain relationship of recycled fine glass aggregate concrete are given, which can satisfactorily describe the effect of the recycled fine glass aggregate on the SSC.

Study on modulation of near infrared radiation based on plasma photonic crystal

Hao Jiong-Ju,Xie Xun,Gu Ke-Da,Liu Yu-Jie,Xia Lei,Yang Hong-Wei 한국물리학회 2020 Current Applied Physics Vol.20 No.8

In this paper, a plasma photonic crystal (PPC) for infrared radiation modulation which is composed of indium tin oxide (ITO) and plasma is proposed. The performance of plasma photonic crystal in near infrared radiation modulation is researched by transfer matrix method (TMM). The simulation results show that the near infrared radiation pass band can be adjusted by the changing of plasma frequency of plasma. The reflection to near infrared radiation by plasma photonic crystal increases with plasma frequency and that of absorption decreases. In addition, the modulation performance of the plasma photonic crystal at different incidence wave angles is also studied. The results show that the incident wave angles have little effect on the transmission of plasma photonic crystal in near infrared band. The reflection of the plasma photonic crystal to near infrared radiation decreases with increasing of the incident wave angle, but that of the absorption increases with the incident wave angle. Therefore, the proposed plasma photonic crystal has a potential application in tunable near infrared filter devices.

Anti-inflammatory, anti-oxidative stress effect of Phascolosoma esculenta oligosaccharides on Escherichia coli-induced sepsis mice

Zhihao Yang,Ying Pan,Jiong Chen,Hao Zhang,Hua Wei,Zufang Wu,Lianliang Liu 한국식품과학회 2019 Food Science and Biotechnology Vol.28 No.6

Bacterial infection is the most common cause ofsepsis. In this study, Phascolosoma esculenta oligosaccharides(PEOs) were prepared to evaluate their resistanceagainst E. coli-induced sepsis. HPLC–MS and FT-IRindicated that PEOs were composed of D-glucosyl, Dgalactosyl,with small amount of D-mannosyl, D-arabinosyland residues with a- and b-type linkage. Different dosageadministrations of PEOs for 30 days significantly improvedICR mice survival rate and bacterial clearance ability(P\0.01) after as E. coli injection. Moreover, PEOs significantlyreduced the secretion of IL-1b and TNF-a andenhanced that of IL-10 in sepsis mice, enhanced theantioxidant enzyme activities and total antioxidant capacity,decreased MDA level in the serum, and upregulatedmRNA expression of Nrf2 (P\0.01). All these resultsindicate that PEOs could improve the resistance of ICRmice against E. coli-induced sepsis that attributed to antiinflammatoryand anti-oxidative stress.

The Pathway and Regulation of Salicylic Acid Biosynthesis in Probenazole-Treated Arabidopsis

Jin Yu,Jiong Gao,Xiao Yan Wang,Qiang Wei,Li Feng Yang,Kai Qiu,Ben Ke Kuai 한국식물학회 2010 Journal of Plant Biology Vol.53 No.6

Probenazole (PBZ; 3-allyloxy-1,2-benzisothiazole-1,1-dioxide) is a highly effective chemical inducer of systemic-acquired resistance (SAR). It has been used widely to protect rice plants against the rice blast fungus Magnaporthe grisea. Previous studies have shown that PBZ induces SAR through enhanced accumulation of salicylic acid (SA). Plants synthesize SA by either a pathway that uses phenylalanine as substrate or another that involves isochorismate. To clarify how SA is produced in PBZ-treated Arabidopsis, we examined the expression patterns and enzyme activities of phenylalanine ammonia lyase (PAL) and isochorismate synthase (ICS), which are the main components of the phenylalanine and isochorismate pathways, respectively. PBZ exposure significantly improved the accumulation of SA and increased ICS activity. In the sid2–2 mutant, which has a defect in ICS1,PBZ had no effect on the level of endogenous SA or activity of ICS. In contrast, PAL activity and the expression of most PAL genes were down-regulated by such treatment in wild-type plants. These results suggest that SA is mainly synthesized via the ICS-mediated pathway in Arabidopsis.