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The evolution of surgical and medical treatment of aortic root aneurysm

null

《医学前沿(英文)》 2014年 第8卷 第4期   页码 427-432 doi: 10.1007/s11684-014-0385-4

摘要:

Since first report of aortic root replacement in 1968, the surgical risk and long term outcome of patients with aortic root aneurysm have been continuously improving. In the last 30 years, the surgical approach is also evolving towards more valve conservation with prophylactical intervention at an earlier clinical stage. Translational research has also led to emerging surgical innovation and new drug therapy. Their efficacies are currently under vigorous clinical trials and evaluations.

关键词: aortic root aneurysm     aortic root replacement     valve sparing root replacement     personalised external aortic root support    

in improving left ventricular remodelling and clinical outcome following surgical and trans-catheter aorticvalve replacement

《医学前沿(英文)》 2021年 第15卷 第3期   页码 416-437 doi: 10.1007/s11684-021-0852-7

摘要: Over the last half century, surgical aortic valve replacement (SAVR) has evolved to offer a durable and efficient valve haemodynamically, with low procedural complications that allows favourable remodelling of left ventricular (LV) structure and function. The latter has become more challenging among elderly patients, particularly following trans-catheter aortic valve implantation (TAVI). Precise understanding of myocardial adaptation to pressure and volume overloading and its responses to valve surgery requires comprehensive assessments from aortic valve energy loss, valvular-vascular impedance to myocardial activation, force-velocity relationship, and myocardial strain. LV hypertrophy and myocardial fibrosis remains as the structural and morphological focus in this endeavour. Early intervention in asymptomatic aortic stenosis or regurgitation along with individualised management of hypertension and atrial fibrillation is likely to improve patient outcome. Physiological pacing via the His-Purkinje system for conduction abnormalities, further reduction in para-valvular aortic regurgitation along with therapy of angiotensin receptor blockade will improve patient outcome by facilitating hypertrophy regression, LV coordinate contraction, and global vascular function. TAVI leaflet thromboses require anticoagulation while impaired access to coronary ostia risks future TAVI-in-TAVI or coronary interventions. Until comparable long-term durability and the resolution of TAVI related complications become available, SAVR remains the first choice for lower risk younger patients.

关键词: surgical aortic valve replacement     trans-catheter aortic valve implantation     left ventricular hypertrophy and fibrosis     myocardial force-velocity relationship     His-Purkinje pacing     renin-angiotensin system inhibitors     coronary access impairment    

Evaluation of the harmonic scalpel in open surgery for abdominal aortic aneurysm

null

《医学前沿(英文)》 2012年 第6卷 第1期   页码 85-88 doi: 10.1007/s11684-012-0174-x

摘要:

The harmonic scalpel is a hemostatic device primarily designed for use in laparoscopic surgery. During the last few years, many surgeons have begun to use the harmonic scalpel in open surgery. Several papers have cited the benefits of the device compared with conventional knot-tying techniques; however, no evidence showing the advantages of using the harmonic scalpel in complicated abdominal aortic aneurysm (AAA) surgery has been presented. The aim of the present study is to determine the value of the harmonic scalpel in open operation for AAA. A total of 153 patients who underwent open surgery for AAA at the Department of Vascular Surgery of Guangdong General Hospital, China between January 2001 and December 2010, were retrospectively analyzed. Open surgery performed with the harmonic scalpel on 105 patients was compared with open operation using conventional knot-tying techniques on 48 patients. The operative time, intraoperative blood loss, total postoperative drainage fluid volumes, hospital stay, and postoperative complications between the two groups were compared. The harmonic scalpel group was associated with a shorter operation time (113.2±23.6 min vs. 232.1±39.2 min, P<0.01) and lower intraoperative blood loss (126.1±96.6 ml vs. 592.1±207.2 ml, P<0.01). Postoperative drainage fluid volumes were greater in the conventional surgery group than in the harmonic scalpel group (702.1±192.8 ml vs. 198.5±97.4 ml, P<0.01). The hospital stay was shorter for the harmonic scalpel group than for the conventional surgery group (10.7±3.3 d vs. 16.5±4.7 d, P<0.05). No differences between the postoperative complications or hospital mortality of the two groups were found. The harmonic scalpel is a safe and minimally invasive tool in open surgery for AAA and is associated with shorter operative time, shorter hospital stay, and lower intraoperative blood loss and postoperative drainage fluid volumes compared with conventional knot-tying techniques.

关键词: abdominal aortic aneurysm     harmonic scalpel     minimally invasive    

engineering in the construction of numerical simulation oriented patient-specific model of stented aortic

Xianlong MENG, Wenyu FU, Yun ZHANG, Aike QIAO,

《机械工程前沿(英文)》 2010年 第5卷 第3期   页码 328-335 doi: 10.1007/s11465-010-0026-9

摘要: Patient-specific models are widely used in hemodynamic simulations. The flow in the boundary layer changes so strongly that fine meshes in the boundary layer are required in numerical simulations, especially for the calculation of wall shear stress and its gradient. To precisely analyze hemodynamics, it is necessary to investigate the approaches to the reconstruction of a numerical simulation-oriented patient-specific model for aortic arch aneurysm that can perform particular meshing in the boundary layer. Based on a surface model of aortic arch aneurysm in STL format, reverse engineering concept was applied to reconstruct a solid model using CAD software Geomagic and Pro/E, and a simplified model of stent for the intervention of aortic arch aneurysm was also created. After these models were imported to ANSYS, a block modeling approach was employed to divide the whole model into several domain blocks to adopt different meshing strategies. Particular meshing was performed especially in the boundary layer and around the stents. The finite element model particularly suitable for numerical simulation of hemodynamics was obtained. Hemodynamic simulation was performed, using the constructed finite element model to verify its applicability. The results indicate that reverse engineering concept and the proposed block modeling approach can be used to divide the solid model of aortic arch aneurysm into multiple volumes, which can be meshed according to particular requirements in each volume; the finite element model of stented aortic arch aneurysm can be employed to simulate hemodynamics. The approaches of modeling were applicable not only for aortic arch aneurysm, but also for similar model reconstruction as a reference in hemodynamic simulation investigations.

关键词: reverse engineering     aortic arch aneurysm     surface model     meshing     finite element model    

Identification of variants associated with sporadic thoracic aortic dissection: a case--control study

《医学前沿(英文)》 2021年 第15卷 第3期   页码 438-447 doi: 10.1007/s11684-020-0826-1

摘要: Thoracic aortic dissection (TAD) without familial clustering or syndromic features is known as sporadic TAD (STAD). So far, the genetic basis of STAD remains unknown. Whole exome sequencing was performed in 223 STAD patients and 414 healthy controls from the Chinese Han population (N = 637). After population structure and genetic relationship and ancestry analyses, we used the optimal sequence kernel association test to identify the candidate genes or variants of STAD. We found that COL3A1 was significantly relevant to STAD (P = 7.35 × 10−6) after 10 000 times permutation test (P = 2.49 × 10−3). Moreover, another independent cohort, including 423 cases and 734 non-STAD subjects (N = 1157), replicated our results (P = 0.021). Further bioinformatics analysis showed that COL3A1 was highly expressed in dissected aortic tissues, and its expression was related to the extracellular matrix (ECM) pathway. Our study identified a profile of known heritable TAD genes in the Chinese STAD population and found that COL3A1 could increase the risk of STAD through the ECM pathway. We wanted to expand the knowledge of the genetic basis and pathology of STAD, which may further help in providing better genetic counseling to the patients.

关键词: sporadic thoracic aortic dissection     exome sequencing     gene COL3A1     case–control study     extracellular matrix    

Aneurysmal dilatation of the aortic sinuses of Valsalva — beyond Marfan syndrome: a single centre experience

null

《医学前沿(英文)》 2014年 第8卷 第4期   页码 419-426 doi: 10.1007/s11684-014-0383-6

摘要:

Aneurysmal dilatation of the aortic sinuses of Valsalva has been most extensively documented in the setting of aortopathies, particularly Marfan syndrome. On the other hand, there is limited data in the literature about congenital sinus of Valsalva aneurysms outside this context. For the purpose of this review, we carried out a literature search on aneurysmal dilatation of the sinuses of Valsalva in Marfan syndrome, and compared this with congenital sinus of Valsalva aneurysms, also including data from a case series from our institution. In conclusion, there are differences in management of aortic dilatation in Marfan syndrome and congenital sinus of Valsalva aneurysms. Though less well-recognised, congenital aneurysms are often associated with significant morbidity and mortality and timely intervention is necessary.

关键词: sinus of Valsalva aneurysms     Marfan syndrome     aortic dissection    

Right coronary occlusion following transcatheter aortic valve implantation: two case reports

null

《医学前沿(英文)》 2016年 第10卷 第3期   页码 351-355 doi: 10.1007/s11684-016-0465-8

摘要:

This paper discusses two male patients with severe aortic stenosis, whose right coronary arteries (RCA) were completely occluded during transcatheter aortic valve implantation (TAVI), leading to fatal hemodynamic disorder. Occlusions of RCA complicated by TAVI are rare. In addition, emergency cardiopulmonary bypass (CPB) played a critical role in rescuing our second patient. Both patients were admitted for “severe aortic stenosis,” and TAVIs were performed. The first patient’s blood pressure immediately dropped to 70/40 mmHg after the balloon expansion and did not increase much after the administration of aramine or fluid therapy. He did not receive emergency surgery and died after 1.5 h of resuscitation. The second patient’s blood pressure fluctuated greatly for several minutes after the valve implantation, ranging from 170/100 mmHg to 60/40 mmHg. Angiography revealed a total occlusion of RCA. Thoracic surgery with CPB was performed, and the patient survived.

关键词: aortic stenosis     transcatheter aortic valve implantation     right coronary occlusion     cardiac group    

Clinical significance of para-aortic lymph node dissection and prognosis in ovarian cancer

null

《医学前沿(英文)》 2014年 第8卷 第1期   页码 96-100 doi: 10.1007/s11684-014-0316-4

摘要:

Lymph node metastasis has an important effect on prognosis of patients with ovarian cancer. Moreover, the impact of para-aortic lymph node (PAN) removal on patient prognosis is still unclear. In this study, 80 patients were divided into groups A and B. Group A consisted of 30 patients who underwent PAN+ pelvic lymph node (PLN) dissection, whereas group B consisted of 50 patients who only underwent PLN dissection. Analysis of the correlation between PAN clearance and prognosis in epithelial ovarian cancer was conducted. Nineteen cases of lymph node metastasis were found in group A, among whom seven cases were positive for PAN, three cases for PLN, and nine cases for both PAN and PLN. In group B, 13 cases were positive for lymph node metastasis. Our study suggested that the metastatic rate of lymph node is 40.0%. Lymph node metastasis was significantly correlated with FIGO stage, tumor differentiation, and histological type both in groups A and B (P<0.05). In groups A and B, the three-year survival rates were 77.9% and 69.0%, and the five-year survival rates were 46.7% and 39.2%, respectively. However, the difference was not statistically significant (P>0.05). The three-year survival rates of PLN metastasis in groups A and B were 68.5% and 41.4%, and the five-year survival rates were 49.7% and 26.4%, respectively. Furthermore, PLN-positive patients who cleared PAN had significantly higher survival rate (P=0.044). In group A, the three-year survival rates of positive and negative lymph nodes were 43.5% and 72.7%, and the five-year survival rates were 27.2% and 58.5%, respectively. The difference was statistically significant (P=0.048). Cox model analysis of single factor suggested that lymph node status affected the survival rate (P<0.01), which was the death risk factor. Consequently, in ovarian carcinoma cytoreductive surgery, resection of the para-aortic lymph node, which has an important function in clinical treatment and prognosis of patients with ovarian cancer, is necessary.

关键词: ovarian cancer     para-aortic lymph node     pelvic lymph node    

Alternate partial root-zone irrigation with high irrigation frequency improves root growth and reduces

Shaoqing DU, Ling TONG, Shaozhong KANG, Fusheng LI, Taisheng DU, Sien LI, Risheng DING

《农业科学与工程前沿(英文)》 2018年 第5卷 第2期   页码 188-196 doi: 10.15302/J-FASE-2017176

摘要: Alternate partial root-zone irrigation (APRI) can improve water use efficiency in arid areas. However, the effectiveness and outcomes of different frequencies of APRI on water uptake capacity and physiological water use have not been reported. A two-year field experiment was conducted with two irrigation amounts (400 and 500 mm) and three irrigation methods (conventional irrigation, APRI with high and low frequencies). Root length density, stomatal conductance, photosynthetic rate, transpiration rate, leaf water use efficiency, midday stem and leaf water potentials were measured. The results show that in comparison with conventional irrigation, APRI with high frequency significantly increased root length density and decreased water potentials and stomatal conductance. No differences in the above indicators between the two APRI frequencies were detected. A significantly positive relationship between stomatal conductance and root length density was found under APRI. Overall, alternate partial root-zone irrigation with high frequency has a great potential to promote root growth, expand water uptake capacity and reduce unproductive water loss in the arid apple production area.

关键词: alternate partial root-zone irrigation     apple tree     leaf water use efficiency     root length density     stomatal conductance     water potential    

ROLE OF NITROGEN SENSING AND ITS INTEGRATIVE SIGNALING PATHWAYS IN SHAPING ROOT SYSTEM ARCHITECTURE

《农业科学与工程前沿(英文)》 2022年 第9卷 第3期   页码 316-332 doi: 10.15302/J-FASE-2022441

摘要:

● The Green Revolution broadened the trade-off between yield and nitrogen-use efficiency.

关键词: Nitrogen     root system architecture     phytohormone     crosstalk     nitrogen-use efficiency     breeding strategy    

Effects of previous drying of sediment on root functional traits and rhizoperformance of emerged macrophytes

《环境科学与工程前沿(英文)》 2021年 第15卷 第6期 doi: 10.1007/s11783-021-1427-1

摘要:

• Sediment desiccation alters morphological characteristics of aquatic sediment.

关键词: Fibrous-root macrophytes     Thick-root macrophytes     Nutrients removal     Wet sediment     Dried-rewetted sediment    

Optimizing hairy root production from explants of

Zhaogui YAN, Shengyu LIU, Junlian ZHANG, Guan HUANG, Lijun DUAN, Yaomei YE

《农业科学与工程前沿(英文)》 2020年 第7卷 第4期   页码 513-522 doi: 10.15302/J-FASE-2019272

摘要:

is a shrub that has been used in traditional herbal medicine. It has great pharmaceutical potential for treating diseases such as cancer and diabetes. As a prerequisite for propagation of this species on a large scale, hairy roots in were induced using and various factors affecting hairy root induction and growth evaluated. Seven factors were tested: (1) type of explant, (2) type of culture medium, (3) duration of pre-culture, (4) inoculum cell density, (5) duration of infection, (6) acetosyringone concentration in the culture medium, and (7) duration of incubation. The optimal protocol for hairy root induction and growth was: young shoots, pre-cultured in Y1 for 2 d, inoculated with broth with an OD of 0.6 for 20 min, and incubated for 3 d. Putative transgenic hairy roots were initially identified by morphology and then confirmed by polymerase chain reaction. Successful and optimal production of hairy roots is a critical prerequisite for industrial scale clonal propagation of . Being able to cultivate the plant on a large scale will provide rapid and ready supply of the plant materials that can be used in herbal medicine and in scientific and industrial exploitation.

关键词: hairy root induction     medicinal plant     MS growth medium     Phyllanthus hainanensis     Rhizobium rhizogenes    

Effect of fly ash replacement level on the fracture behavior of concrete

Mahdi AREZOUMANDI, Jeffery S. VOLZ

《结构与土木工程前沿(英文)》 2013年 第7卷 第4期   页码 411-418 doi: 10.1007/s11709-013-0228-4

摘要: The production of portland cement–the key ingredient in concrete–generates a significant amount of carbon dioxide. However, due to its incredible versatility, availability, and relatively low cost, concrete is the most consumed manmade material on the planet. One method of reducing concrete’s contribution to greenhouse gas emissions is the use of fly ash to replace a significant amount of the cement. ?This study presents the results of an experimental investigation that evaluates effect of fly ash replacement level on the fracture energy of concrete. This study includes four mixes with 0%, 30%, 50%, and 70% fly ash as a cement replacement. This experimental program consisted of 32 fracture beams to study the fracture behavior of concrete. The experimental fracture energies were compared with the fracture energy provisions of different design codes and also different analytical equations. Furthermore, statistical data analyses (parametric and non-parametric) were performed to evaluate whether or not there is any statistically significant difference between the experimental fracture energies of different mixes. Results of these statistical tests show that the mix with higher level of fly ash replacement level has higher fracture energy.

关键词: concrete     fracture energy     fly ash    

Endosulfan residues and farmers’ replacement behaviors of endosulfan in the north-west inland cotton

《环境科学与工程前沿(英文)》 2023年 第18卷 第4期 doi: 10.1007/s11783-024-1803-8

摘要:

● The situation of endosulfan residues in cotton fields were assessed.

关键词: Cotton fields     Endosulfan residues     Farmers     KAP survey     Replacement behaviours    

Improving the efficiency and effectiveness of global phosphorus use: focus on root and rhizosphere levels

null

《农业科学与工程前沿(英文)》 2019年 第6卷 第4期   页码 357-365 doi: 10.15302/J-FASE-2019275

摘要:

Phosphorus (P) is essential for life and for efficient crop production, but global P use with limited recycling is inefficient in several sectors, including agronomy. Unfortunately, plant physiologists, agronomists, farmers and end users employ different measures for P use efficiency (PUE), which often masks their values at different scales. The term P use effectiveness, which also considers energetic and sustainability measures in addition to P balances, is also a valuable concept. Major physiological and genetic factors for plant P uptake and utilization have been identified, but there has been limited success in genetically improving PUE of modern crop cultivars. In maize, studies on root architectural and morphological traits appear promising. Rhizosphere processes assist in mobilizing and capturing sparingly soluble phosphate from rock phosphate. Combinations of phosphate-solubilizing microorganisms with ammonium-based nitrogen fertilizer, as well as strategies of fertilizer placement near the roots of target crops, can moderately enhance PUE. The desired concentration of P in the products differs, depending on the final use of the crop products as feed, food or for energy conversion, which should be considered during crop production.

关键词: acquisition efficiency     plant growth promoting rhizobacteria     phosphate     use efficiency     utilization efficiency    

标题 作者 时间 类型 操作

The evolution of surgical and medical treatment of aortic root aneurysm

null

期刊论文

in improving left ventricular remodelling and clinical outcome following surgical and trans-catheter aorticvalve replacement

期刊论文

Evaluation of the harmonic scalpel in open surgery for abdominal aortic aneurysm

null

期刊论文

engineering in the construction of numerical simulation oriented patient-specific model of stented aortic

Xianlong MENG, Wenyu FU, Yun ZHANG, Aike QIAO,

期刊论文

Identification of variants associated with sporadic thoracic aortic dissection: a case--control study

期刊论文

Aneurysmal dilatation of the aortic sinuses of Valsalva — beyond Marfan syndrome: a single centre experience

null

期刊论文

Right coronary occlusion following transcatheter aortic valve implantation: two case reports

null

期刊论文

Clinical significance of para-aortic lymph node dissection and prognosis in ovarian cancer

null

期刊论文

Alternate partial root-zone irrigation with high irrigation frequency improves root growth and reduces

Shaoqing DU, Ling TONG, Shaozhong KANG, Fusheng LI, Taisheng DU, Sien LI, Risheng DING

期刊论文

ROLE OF NITROGEN SENSING AND ITS INTEGRATIVE SIGNALING PATHWAYS IN SHAPING ROOT SYSTEM ARCHITECTURE

期刊论文

Effects of previous drying of sediment on root functional traits and rhizoperformance of emerged macrophytes

期刊论文

Optimizing hairy root production from explants of

Zhaogui YAN, Shengyu LIU, Junlian ZHANG, Guan HUANG, Lijun DUAN, Yaomei YE

期刊论文

Effect of fly ash replacement level on the fracture behavior of concrete

Mahdi AREZOUMANDI, Jeffery S. VOLZ

期刊论文

Endosulfan residues and farmers’ replacement behaviors of endosulfan in the north-west inland cotton

期刊论文

Improving the efficiency and effectiveness of global phosphorus use: focus on root and rhizosphere levels

null

期刊论文