3D Multislice CT Angiography in Post-Aortic Stent Grafting: A Pictorial Essay

Zhonghua Sun 대한영상의학회 2006 Korean Journal of Radiology Vol.7 No.3

Helical CT angiography has been widely used in both pre- and post-aortic stent grafting and it has been confirmed to be the preferred modality when compared to conventional angiography. The recent development of multislice CT (MSCT) has further enhanced the applications of CT angiography for aortic stent grafting. One of the advantages of MSCT angiography over conventional angiography is that the 3D reconstructions, based on the volumetric CT data, provide additional information during follow-up of aortic stent grafting. While endovascular repair has been increasingly used in clinical practice, the use of 3D MSCT imaging in endovascular repair continues to play an important role. In this pictorial essay, we aimed to discuss the diagnostic performance of 3D MSCT angiography in post aortic stent grafting, including the most commonly used surface shaded display, curvilinear reformation, the maximum intensity projection, volume rendering and virtual endoscopy. The advantages and disadvantages of each 3D reconstruction are also explored.

Fenestrated Stent Graft Repair of Abdominal Aortic Aneurysm: Hemodynamic Analysis of the Effect of Fenestrated Stents on the Renal Arteries

Zhonghua Sun,Thanapong Chaichana 대한영상의학회 2010 Korean Journal of Radiology Vol.11 No.1

Objective: We wanted to investigate the hemodynamic effect of fenestrated stents on the renal arteries with using a fluid structure interaction method. Materials and Methods: Two representative patients who each had abdominal aortic aneurysm that was treated with fenestrated stent grafts were selected for the study. 3D realistic aorta models for the main artery branches and aneurysm were generated based on the multislice CT scans from two patients with different aortic geometries. The simulated fenestrated stents were designed and modelled based on the 3D intraluminal appearance, and these were placed inside the renal artery with an intra-aortic protrusion of 5.0-7.0 mm to reflect the actual patients’treatment. The stent wire thickness was simulated with a diameter of 0.4 mm and hemodynamic analysis was performed at different cardiac cycles. Results: Our results showed that the effect of the fenestrated stent wires on the renal blood flow was minimal because the flow velocity was not significantly affected when compared to that calculated at pre-stent graft implantation, and this was despite the presence of recirculation patterns at the proximal part of the renal arteries. The wall pressure was found to be significantly decreased after fenestration, yet no significant change of the wall shear stress was noticed at post-fenestration, although the wall shear stress was shown to decrease slightly at the proximal aneurysm necks. Conclusion: Our analysis demonstrates that the hemodynamic effect of fenestrated renal stents on the renal arteries is insignificant. Further studies are needed to investigate the effect of different lengths of stent protrusion with variable stent thicknesses on the renal blood flow, and this is valuable for understanding the long-term outcomes of fenestrated repair. Objective: We wanted to investigate the hemodynamic effect of fenestrated stents on the renal arteries with using a fluid structure interaction method. Materials and Methods: Two representative patients who each had abdominal aortic aneurysm that was treated with fenestrated stent grafts were selected for the study. 3D realistic aorta models for the main artery branches and aneurysm were generated based on the multislice CT scans from two patients with different aortic geometries. The simulated fenestrated stents were designed and modelled based on the 3D intraluminal appearance, and these were placed inside the renal artery with an intra-aortic protrusion of 5.0-7.0 mm to reflect the actual patients’treatment. The stent wire thickness was simulated with a diameter of 0.4 mm and hemodynamic analysis was performed at different cardiac cycles. Results: Our results showed that the effect of the fenestrated stent wires on the renal blood flow was minimal because the flow velocity was not significantly affected when compared to that calculated at pre-stent graft implantation, and this was despite the presence of recirculation patterns at the proximal part of the renal arteries. The wall pressure was found to be significantly decreased after fenestration, yet no significant change of the wall shear stress was noticed at post-fenestration, although the wall shear stress was shown to decrease slightly at the proximal aneurysm necks. Conclusion: Our analysis demonstrates that the hemodynamic effect of fenestrated renal stents on the renal arteries is insignificant. Further studies are needed to investigate the effect of different lengths of stent protrusion with variable stent thicknesses on the renal blood flow, and this is valuable for understanding the long-term outcomes of fenestrated repair.

Multislice CT Virtual Intravascular Endoscopy for Assessing Pulmonary Embolisms: a Pictorial Review

Zhonghua Sun,Sultan Ayed Al Dosari,Curtise Ng,Ali al-Muntashari,Saud Almaliky 대한영상의학회 2010 Korean Journal of Radiology Vol.11 No.2

Multislice CT has been widely used in clinical practice for diagnosing cardiovascular disease due to its reduced invasiveness and its high spatial and temporal resolution. As a reliable alternative to conventional pulmonary angiography, multislice CT angiography has been recognized as the first line technique for detecting and diagnosing pulmonary embolism. A pulmonary embolism located in the main pulmonary artery, as well as being located in the segmental branches, can be accurately detected with multislice CT imaging, and especially with the use of 16-and 64-slice CT scanners. Visualization of pulmonary embolisms has traditionally been limited to 2D, multiplanar reformation and the 3D external surface visualizations. In this pictorial review, we present our experience of using 3D virtual intravascular endoscopy to characterize and evaluate the intraluminal appearance of pulmonary embolisms in a group of patients who were suspected of having pulmonary embolism and who were undergoing multislice CT angiography. We expect that the research findings from this study will provide insight into the extent of disease and the luminal changes to the pulmonary arteries that are due to the presence of thrombus, and so monitoring of the progress of disease and predicting the treatment outcome can well be achieved.

Multislice CT Angiography of Fenestrated Endovascular Stent Grafting for Treating Abdominal Aortic Aneurysms: a Pictorial Review of the 2D/3D Visualizations

Zhonghua Sun,Bibombe P Mwipatayi,Yvonne B Allen,David E Hartley,Michael M Lawrence-Brown 대한영상의학회 2009 Korean Journal of Radiology Vol.10 No.3

Fenestrated endovascular repair of an abdominal aortic aneurysm has been developed to treat patients with a short or complicated aneurysm neck. Fenestration involves creating an opening in the graft fabric to accommodate the orifice of the vessel that is targeted for preservation. Fixation of the fenestration to the renal arteries and the other visceral arteries can be done by implanting bare or covered stents across the graft-artery ostia interfaces so that a portion of the stent protrudes into the aortic lumen. Accurate alignment of the targeted vessels in a longitudinal aspect is hard to achieve during stent deployment because rotation of the stent graft may take place during delivery from the sheath. Understanding the 3D relationship of the aortic branches and the fenestrated vessel stents following fenestration will aid endovascular specialists to evaluate how the stent graft is situated within the aorta after placement of fenestrations. The aim of this article is to provide the 2D and 3D imaging appearances of the fenestrated endovascular grafts that were implanted in a group of patients with abdominal aortic aneurysms, based on the multislice CT angiography. The potential applications of each visualization technique were explored and compared with the 2D axial images.

Key Technology for Food-Safety Traceability Based on a Combined Two-Dimensional Code

Zhonghua Li,Xinghua Sun,Ting Yan,Dong Yang,Guiliang Feng 한국정보처리학회 2023 Journal of information processing systems Vol.19 No.2

Current food-traceability platforms suffer from problems such as inconsistent traceability standards, a lack ofpublic credibility, and slow access to data. In this work, a combined code and identification method wasdesigned that can achieve more secure product traceability using the dual anti-counterfeiting technology of aQR code and a hidden code. When the QR code is blurry, the hidden code can still be used to effectively identifyfood information. Based on this combined code, a food-safety traceability platform was developed. Theplatform follows unified encoding standards and provides standardized interfaces. Based on this innovation,the platform not only can serve individual food-traceability systems development, but also connect existingtraceability systems. These will help to solve the problems such as non-standard traceability content,inconsistent processes, and incompatible system software. The experimental results show that the combinedcode has higher accuracy. The food-safety traceability platform based on the combined code improves thesafety of the traceability process and the integrity of the traceability information. The innovation of this paperis invoking the combined code united the QR code‘s rapidity and the hidden code‘s reliability, developing aplatform that uses a unified coding standard and provides a standardized interface to resolve the differencesbetween multi-food-traceability systems. Among similar systems, it is the only one that has been connected tothe national QR code identification platform. The project has made profits and has significant economic andsocial benefits.

Fragmentation and development of preimplantation porcine embryos derived by parthenogenetic activation and nuclear transfer

Im, Gi-Sun,Yang, Boh-Suk,Lai, Liangxue,Liu, Zhonghua,Hao, Yanhong,Prather, Randall S. JOHN WILEY & SONS LTD 2005 Molecular Reproduction and Development Vol.71 No.2

<P>Fragmentation occurs during early developmental stages of electrically activated oocytes and nuclear transfer (NT) embryos. It might contribute to the low developmental rate of porcine NT embryos. The present study was conducted to investigate whether the addition of sugars such as sorbitol or sucrose suppresses fragmentation and supports the development of electrically activated oocytes and NT embryos. The activated oocytes were cultured in Porcine Zygote Medium-3 (PZM-3) supplemented with sorbitol or sucrose for 2 days after electric activation, and then cultured in the PZM-3 for the remaining 4 days. The osmolarities of PZM-3, PZM-3 supplemented with 0.05 or 0.1 M sorbitol, and PZM-3 with 0.05 M sucrose were 269 ± 6.31, 316 ± 3.13, 362 ± 4.37, and 315 ± 5.03 mOsm, respectively. When parthenogentically activated oocytes were cultured in PZM-3 supplemented with 0.05 M sorbitol or sucrose for the first 2 days and then cultured in PZM-3 without sugar, a significantly higher (P < 0.05) cleavage rate and blastocyst rate were observed. Interestingly, addition of sugar to PZM-3 for 2 days reduced the fragmentation rate compared to PZM-3 without sugar. In NT embryos, sugar addition into PZM-3 increased the fusion rate (84.2% ± 6.07 vs. 95.1% ± 2.52), cleavage rate (67.6% ± 5.80 vs. 77.3% ± 3.03), and developmental rate to the blastocyst stage (10.2% ± 0.79 vs. 19.4% ± 1.77). There was no significant difference between treatments for the number of the blastocysts. In addition the fragmentation rate was reduced compared to PZM-3 without sorbitol (26.1 ± 4.30 vs. 14.5 ± 1.74). In conclusion, increasing the osmolarity of PZM-3 through addition of either sorbitol or sucrose for 48 hr increased the cleavage and developmental rate to the blastocyst stage by reducing the fragmentation rate through increasing osmolarity. Mol. Reprod. Dev. 71: 159–165, 2005. © 2005 Wiley-Liss, Inc.</P>

Synthesis of novel oleanolic acid and ursolic acid in C-28 position derivatives as potential anticancer agents

Tian Tian,Xinyu Liu,이응석,Jingyang Sun,Zhonghua Feng,Long-Xuan Zhao,Chunhui Zhao 대한약학회 2017 Archives of Pharmacal Research Vol.40 No.4

A series of nitrogen-containing derivatives ofoleanolic acid and ursolic acid were prepared by a modificationat C-28 position via esterification with 2-hydroxyaceticacid followed by amidation with amines, such aspiperazine, N-methylpiperazine, and alkane-1, 2-diamines,alkane-1, 4-diamines, alkane-1, 6-diamines. In vitroantiproliferative activities of the compounds preparedtowards MCF-7, Hela and A549 cell lines were evaluatedby a MTT method to show that OA-5a, OA-5b, OA-5c andUA-5a showed somewhat improved antiproliferativeactivities against MCF-7, Hela and A549 cells comparingto that of the positive control, gefitinib.

이동폐색 시스템에서 자동운전 속도 프로파일 산출 방법

최동혁(Dong-Hyuk Choi),조찬호(Chan-Ho Cho),전종화(Zhonghua Quan),최선아(Sun-Ah Choi),류명선(Myung-Seon Ryou) 한국철도학회 2011 한국철도학회 학술발표대회논문집 Vol.2011 No.10

This paper is concerned with the ATO speed profile generation method in the moving block system. The ATO speed profile is calculated using the acceleration limit and the jerk limit to improve ride comfort. In addition the speed limit and stop distance provided from ATP profile should be considered to ensure safety. In the moving block system the speed limit and the stop position are frequently changed in real-time. Therefore the ATO speed profile should be regenerated immediately according to change of the speed limit and the stop position within the acceleration limit and the jerk limit. In this paper the ATO speed profile generation method is proposed which considers not only frequent changes of the speed limit and the stop position but also acceleration limit and jerk limit. Futhermore the simulation result is presented to verify usefulness of this method.

Expression of DNA Damage Response Proteins and Associations with Clinicopathologic Characteristics in Chinese Familial Breast Cancer Patients with BRCA1/2 Mutations

Xinyi Zhu,Tian Tian,Miao Ruan,Jia Rao,Wentao Yang,Xu Cai,Menghong Sun,Guangqi Qin,Zhonghua Zhao,Jiong Wu,Zhimin Shao,Ruohong Shui,Zhen Hu 한국유방암학회 2018 Journal of breast cancer Vol.21 No.3

Purpose: The characteristic expression of DNA damage response proteins in familial breast cancers with BRCA1, BRCA2, or non-BRCA1/2 mutations has not been analyzed in Chinese patients. Our study aimed to assess the differential expression of microcephalin 1 (BRIT1), ATM serine/threonine kinase (ATM), checkpoint kinase 2 (CHEK2), BRCA1, RAD51 recombinase (RAD51), and poly (ADP-ribose) polymerase 1 (PARP-1) and establish the profile of Chinese familial breast cancers with different mutation status. Methods: We constructed five tissue microarrays from 183 familial breast cancer patients (31 with BRCA1 mutations; 14 with BRCA2 mutations, and 138 with non-BRCA1/2 mutations). The DNA response and repair markers used for immunohistochemistry analysis included BRIT1, ATM, CHEK2, BRCA1, RAD51, and PARP-1. The expressions of these proteins were analyzed in BRCA1/2 mutated tumors. The association between pathologic characteristics with BRCA1/2 mutation status was also analyzed. Results: In familial breast cancer patients, BRCA1 mutated tumors were more frequent with high nuclear grade, estrogen receptor/progesterone receptor/human epidermal growth factor receptor 2 negative, low Ki-67, and positive CK5/6. BRCA1 mutated tumors had lower CHEK2 and higher cytoplasmic BRIT1 expression than BRCA2 and non-BRCA1/2 mutation tumors. BRCA2-associated tumors showed higher CHEK2 and cytoplasmic RAD51 expression than those in other groups. Nuclear PARP-1 expression in BRCA1/2-associated tumors was significantly higher than in non-BRCA1/2 mutation tumors. Moreover, we found quite a few of negative PARP-1 expression cases in BRCA1/2 mutated groups. Conclusion: The clinicopathologic findings of BRCA1-associated Chinese familial breast cancers were similar to the results of other studies. Chinese familial breast cancer patients with BRCA1/2 mutations might have distinctive expression of different DNA damage response proteins. The reduced expression of PARP-1 in Chinese BRCA1/2 mutated breast cancer patients could influence the therapeutic outcome of PARP-1 inhibitors.