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Emerging roles of podoplanin in vascular development and homeostasis

null

《医学前沿(英文)》 2015年 第9卷 第4期   页码 421-430 doi: 10.1007/s11684-015-0424-9

摘要:

Podoplanin (PDPN) is a mucin-type O-glycoprotein expressed in diverse cell types, such as lymphatic endothelial cells (LECs) in the vascular system and fibroblastic reticular cells (FRCs) in lymph nodes. PDPN on LECs or FRCs activates CLEC-2 in platelets, triggering platelet activation and/or aggregation through downstream signaling events, including activation of Syk kinase. This mechanism is required to initiate and maintain separation of blood and lymphatic vessels and to stabilize high endothelial venule integrity within lymph nodes. In the vascular system, normal expression of PDPN at the LEC surface requires transcriptional activation of Pdpn by Prox1 and modification of PDPN with core 1-derived O-glycans. This review provides a comprehensive overview of the roles of PDPN in vascular development and lymphoid organ maintenance and discusses the mechanisms that regulate PDPN expression related to its function.

关键词: podoplanin     CLEC-2     Prox1     O-glycosylation     lymphatic vascular development and maintenance     lymphoid organ homeostasis    

Development and application of an off-site maintenance system in the petrochemical industry

Ruisheng YONG, Yanbing YE, Hanbin LUO, Lieyun DING

《工程管理前沿(英文)》 2017年 第4卷 第2期   页码 111-126 doi: 10.15302/J-FEM-2017027

摘要: On-site maintenance (ONSM) is critical to ensuring the safety of equipment in the petrochemical industry. However, many accidents occur during ONSM processes because of unstable equipment, complicated work environment, and human error. To reduce congestion and exposure to hazards during on-site operations and thereby reduce the probability of accidents, off-site maintenance (OFSM) is proposed based on Energy Release Theory (ERT). The information requirements for OFSM are analyzed. A support system for OFSM, which makes use of visualization, information management, and localization capabilities, is developed. A case study utilizing OFSM and its support system for an oil-loading facility of a petrochemical company is conducted. The application results indicated that implementation of OFSM system can significantly reduce the operation risks and can improve the operation efficiency.

关键词: on-site maintenance     petrochemical industry     safety     off-site maintenance system    

民航视情维修决策优化模型发展

张海军,左洪福,梁剑,戎翔

《中国工程科学》 2005年 第7卷 第11期   页码 17-20

摘要:

目前视情维修是民航业采用的主要维修方式,可以使维修的有效性、经济性大幅度提高。维修决策优化模型对民航维修成本的降低和利润的提升具有显著的指导作用;归纳了视情维修的时间延迟模型、冲击模型、比例危险模型、马尔可夫决策模型等优化模型的建模方法;分析了该类模型在应用中存在的不足,并展望了其发展前景。

关键词: 视情维修     优化模型     决策     成本    

Lymphatic metastasis is related to the epithelial-mesenchymal transition and expressions of VEGF, MMP

Lihui WANG, Lianhong LI, Shen LV, Shujun FAN, Li ZHAN, Bo WANG, Zhong ZHANG

《医学前沿(英文)》 2009年 第3卷 第2期   页码 164-170 doi: 10.1007/s11684-009-0038-1

摘要: The invasion and metastasis of breast cancer are supposed to involve several stages in which epithelial-mesenchymal transition (EMT) is regarded as the mechanistic basis for the behavior of cancer cells. A series of factors related to EMT are apparently involved in such process. The current study aimed to investigate the contributions of EMT and related factors in lymph node metastasis of breast cancer. The expressions of E-cadherin (E-Cad), N-cadherin (N-Cad), vascular endothelial cell growth factor (VEGF), matrix metalloproteinase-9 (MMP-9), cyclooxygenase-2 (COX-2), and CD34 were examined in 74 cases of breast cancer, including 39 cases with lymph node metastasis and 35 cases without lymph node metastasis by immunohistochemistry. Multivariable Cox proportional hazards model was used to analyze the patients’ prognosis. The expressions of N-Cad, VEGF, MMP-9, and COX-2 in cases with lymph node metastasis were significantly higher than those without lymph node metastasis ( <0.05), while the E-Cad level was inversely related to status of lymph node metastasis ( <0.05). The metastasis rate of lymph node in the cases with EMT (lower E-Cad expression and higher N-Cad expression) was 78.3%, while that without EMT (higher E-Cad expression and lower N-Cad expression) was 11.1%. There was a statistical difference in the expression of COX-2 protein between histological grade I and grade II or III, respectively ( <0.05). In the cases with higher grade, the expression of E-Cad was decreased, while that of N-Cad was increased. Higher microvascular density (MVD) was also found to be significantly associated with lymphatic metastasis ( <0.05), and the cases with higher MVD had shorter survival time. This study indicates that EMT and expressions of VEGF, MMP-9 and COX-2, and MVD value are strongly correlated with lymph node metastasis in breast cancer.

关键词: epithelial-mesenchymal transition     vascular endothelial cell growth factor     matrix metalloproteinase-9     cyclooxygenase-2     higher microvascular density     breast cancer    

Endostatin specifically targets both tumor blood vessels and lymphatic vessels

Wei Zhuo, Yang Chen, Xiaomin Song, Yongzhang Luo

《医学前沿(英文)》 2011年 第5卷 第4期   页码 336-340 doi: 10.1007/s11684-011-0163-5

摘要: Endostatin, a 20 kDa C-terminal fragment of collagen XVIII, was first identified as a potent angiogenic inhibitor. The anti-angiogenic function of endostatin has been well documented during the past decade. Recently, several studies demonstrated that endostatin also inhibits tumor lymphangiogenesis and lymphatic metastasis. However, the exact mechanism that endostatin executes its anti-angiogenic and anti-lymphangiogenic functions remains elusive. In the current mini-review, we briefly summarize recent novel findings, including the functions of endostatin targeting not only angiogenesis but also lymphangiogenesis, and the underlying mechanism by which endostatin internalization regulates its biological functions.

关键词: endostatin     angiogenesis     lymphangiogenesis     nystatin     internalization     tumor    

Risk evaluation for the task transfer of an aircraft maintenance program based on a multielement connection

《工程管理前沿(英文)》 doi: 10.1007/s42524-023-0282-0

摘要: This paper proposes a framework for evaluating the efficacy and suitability of maintenance programs with a focus on quantitative risk assessment in the domain of aircraft maintenance task transfer. The analysis is anchored in the principles of Maintenance Steering Group-3 (MSG-3) logic decision paradigms. The paper advances a holistic risk assessment index architecture tailored for the task transfer of maintenance programs. Utilizing the analytic network process (ANP), the study quantifies the weight interrelationships among diverse variables, incorporating expert-elicited subjective weighting. A multielement connection number-based evaluative model is employed to characterize decision-specific data, thereby facilitating the quantification of task transfer-associated risk through the appraisal of set-pair potentials. Moreover, the paper conducts a temporal risk trend analysis founded on partial connection numbers of varying orders. This analytical construct serves to streamline the process of risk assessment pertinent to maintenance program task transfer. The empirical component of this research, exemplified through a case study of the Boeing 737NG aircraft maintenance program, corroborates the methodological robustness and pragmatic applicability of the proposed framework in the quantification and analysis of mission transfer risk.

关键词: risk evaluation     maintenance steering group     analytic network process     task transfer     maintenance program    

Mechanism of vascular endothelial growth factor on the prevention of restenosis after angioplasty

Qigong LIU, Honglian ZHOU, Yan ZENG, Shan YE, Jiani LIU, Zaiying LU

《医学前沿(英文)》 2009年 第3卷 第2期   页码 177-180 doi: 10.1007/s11684-009-0021-x

摘要: To evaluate the mechanism of vascular endothelial growth factor (VEGF) on the prevention of restenosis after angioplasty, the recombinant adenovirus vector containing hVEGF cDNA was constructed and transfected into vascular smooth muscle cells (VSMC) . The conditioned medium containing VEGF was collected 72 h after the infection. Then, the VSMC and human umbilical vein endothelial cells (HUVEC) were divided into control group, H O -treated group and H O +VEGF-treated group to observe the proliferation and apoptosis by water soluble tetrazolium (WST-1) method, nick end labeling (TUNEL) and flow cytometry (FCM). Compared with the control and H O +VEGF-treated groups, the absorbance ( ) value of HUVEC was decreased, and apoptosis of HUVEC was significantly increased in H O -treated group. The changes of value and apoptosis of VSMC were contrary to those of HUVEC. H O could stimulate the proliferation of VSMC and induce the apoptosis of HUVEC, inhibit the proliferation of HUVEC and the apoptosis of VSMC and induce restenosis. VEGF could inhibit the effect of H O on HUVEC and VSMC and prevent restenosis. These results offered further theoretical evidence for VEGF on the prevention of restenosis after angioplasty.

关键词: vascular endothelial growth factors     restenosis     reactive oxygen species     endothelial cells     vascular smooth muscle cell    

Human reliability in maintenance task

Pacaiova HANA,

《机械工程前沿(英文)》 2010年 第5卷 第2期   页码 184-188 doi: 10.1007/s11465-010-0002-4

摘要: Maintenance management requirements have another dimension in the present as in the past. Looking for the optimal tools of decision processing is hard. The current concepts have represented the integration of theoretical, technical, and management tools whose applications need actual modification. Technical measurements are expensive and take a long time/term, and it is hard to estimate the economical returns. This paper presents the concept of a maintenance management task and its function in preventing major accidents. The importance of considering the reliability of maintenance tasks and the method to reach it are also discussed in this paper.

关键词: maintenance     risk assessment     failure     reliability     prevention    

Crk-associated substrate, vascular smooth muscle and hypertension

TANG Dale

《医学前沿(英文)》 2008年 第2卷 第4期   页码 323-331 doi: 10.1007/s11684-008-0062-6

摘要: Hypertension is characterized by vascular smooth muscle constriction and vascular remodeling involving cell migration, hypertrophy and growth. Crk-associated substrate (CAS), the first discovered member of the adapter protein CAS family, has been shown to be a critical cellular component that regulates various smooth muscle functions. In this review, the molecular structure and protein interactions of the CAS family members are summarized. Evidence for the role of CAS in the regulation of vascular smooth muscle contractility is presented. Contraction stimulation induces CAS phosphorylation on Tyr-410 in arterial smooth muscle, creating the binding site for the Src homology (SH) 2/SH3 protein CrkII, which activates neuronal Wiskott-Aldrich syndrome protein (N-WASP)-mediated actin assembly and force development. The functions of CAS in cell migration, hypertrophy and growth are also summarized. Abelson tyrosine kinase (Abl), c-Src, focal adhesion kinase (FAK), proline-rich tyrosine kinase 2 (PYK2), protein tyrosine phosphatase-proline, glutamate, serine and threonine sequence protein (PTP-PEST) and SHP-2 have been documented to coordinate the phosphorylation and dephosphorylation of CAS. The downstream signaling partners of CAS in the context of cell motility, hypertrophy, survival and growth are also discussed. These new findings establish the important role of CAS in the modulation of vascular smooth muscle functions. Furthermore, the upstream regulators of CAS may be new biologic targets for the development of more effective and specific treatment of cardiovascular diseases such as hypertension.

关键词: Contraction stimulation     phosphatase-proline     molecular structure     discovered     hypertension    

Role of nitric oxide in biological effects of vascular endothelial growth factor

Qigong LIU M D , Yan ZENG , Jiani LIU , Shan YE , Yongdong LI , Zaiying LU M D ,

《医学前沿(英文)》 2009年 第3卷 第3期   页码 284-286 doi: 10.1007/s11684-009-0062-1

摘要: To evaluate the role of nitric oxide in the biological effects of vascular endothelial growth factor (VEGF) and the possible mechanism of VEGF, the cultured vascular endothelial cells of rabbit aorta were divided into control group, VEGF-treated group and VEGF+ -nitro-L-arginine methyl ester (L-NAME)-treated group. The absorbance () value of vascular endothelial cells and the levels of prostaglandin (PGI), endothelin-1 (ET-1) and von Willebrand factor (vWF) in the supernatant were observed by water-soluble tetrazolium salt assay, radioimmunoassay and enzyme-linked immunosorbent assay. The values and PGI in VEGF-treated group and VEGF+L-NAME-treated group were higher than those in control group (<0.05 and <0.01). The ET-1 and vWF were significantly decreased in VEGF-treated group and VEGF+L-NAME-treated group compared with the control (<0.05 and <0.01). These results indicate that VEGF could promote the proliferation and secretion of PGI and inhibit the secretion of ET-1 and vWF in vascular endothelial cells and that L-NAME could inhibit the effect of VEGF partially. Nitric oxide is an important mediator in the process of stimulating proliferation and regulating secretion of vascular endothelial cells by VEGF.

关键词: vascular endothelial growth factor     nitric oxide     N-nitro-L-arginine methyl ester     vascular endothelial cells    

Progress in tumor vascular normalization for anticancer therapy: challenges and perspectives

null

《医学前沿(英文)》 2012年 第6卷 第1期   页码 67-78 doi: 10.1007/s11684-012-0176-8

摘要:

Antitumor angiogenic therapy has been shown promising in the treatment of several advanced cancers since the approval of the first antiangiogenic drug Avastin in 2004. Although the current antiangiogenic drugs reduce the density of tumor blood vessels and result in tumor shrinkage at the early stage of treatment, recent studies have shown that antiangiogenic therapy has transient and insufficient efficacy, resulting in tumor recurrence in patients after several months of treatment. Blockage of blood and oxygen supplies creates a hypoxic and acidic microenvironment in the tumor tissues, which fosters tumor cells to become more aggressive and metastatic. In 2001, Jain proposed tumor vascular normalization as an alternative approach to treating cancers based on the pioneering work on tumor blood vessels by several other researchers. At present, normalizing the disorganized tumor vasculature, rather than disrupting or blocking them, has emerged as a new option for anticancer therapy. Preclinical and clinical data have shown that tumor vascular normalization using monoclonal antibodies, proteins, peptides, small molecules, and pericytes resulted in decreased tumor size and reduced metastasis. However, current tumor vascular normalizing drugs display moderate anticancer efficacy. Accumulated data have shown that a variety of vasculogenic/angiogenic tumor cells and genes play important roles in tumor neovascularization, growth, and metastasis. Therefore, multiple-targeting of vasculogenic tumor cells and genes may improve the efficacy of tumor vascular normalization. To this end, the combination of antiangiogenic drugs with tumor vascular normalizing therapeutics, as well as the integration of Western medicine with traditional Chinese medicine, may provide a good opportunity for discovering novel tumor vascular normalizing drugs for an effective anticancer therapy.

关键词: angiogenesis     vasculogenesis     neovascularization     tumor     vasculature     normalization     traditional Chinese medicine    

sulfate promotes the formation of atherosclerotic lesions and induces plaque instability by targeting vascular

null

《医学前沿(英文)》 2016年 第10卷 第3期   页码 320-329 doi: 10.1007/s11684-016-0463-x

摘要:

Coronary atherosclerosis is a major complication of chronic kidney disease. This condition contributes to the increased mortality in dialysis patients. p-Cresyl sulfate (PCS) is a prototype of protein-bound uremic toxins that cannot be efficiently removed through routine dialysis procedures. In the present study, ApoE−/− mice that underwent 5/6 nephrectomy were randomly divided into two groups, namely, vehicle-treated group (n = 20) and PCS-treated group (n = 20). Mice were sacrificed for en face and immunohistological analyses after 8 or 24 weeks of high-fat diet. Rat aortic vascular smooth muscle cells (VSMCs) were treated with phosphate buffer solution or 500 µmol/L PCS for in vitro evaluation. PCS-treated mice were observed to suffer increased atherosclerotic lesions after eight weeks of PCS administration. Moreover, 24 weeks of PCS administration also markedly increased the vulnerability index of aortic plaques. PCS was also observed to facilitate the migration and proliferation of VSMCs during the progression of the disease. Moreover, PCS disturbed the balance between matrix metalloproteinases and tissue inhibitor of metalloproteinases within the plaques. Thus, PCS played a vital role in promoting atherogenesis and disturbing the stability of formed plaques probably by targeting VSMCs.

关键词: p-cresyl sulfate     atherosclerosis     plaque stability     vascular smooth muscle cell    

Endogenous tissue factor pathway inhibitor in vascular smooth muscle cells inhibits arterial thrombosis

null

《医学前沿(英文)》 2017年 第11卷 第3期   页码 403-409 doi: 10.1007/s11684-017-0522-y

摘要:

Tissue factor pathway inhibitor (TFPI) is the main inhibitor of tissue factor-mediated coagulation. TFPI is expressed by endothelial and smooth muscle cells in the vasculature. Endothelium-derived TFPI has been reported to play a regulatory role in arterial thrombosis. However, the role of endogenous TFPI in vascular smooth muscle cells (VSMCs) in thrombosis and vascular disease development has yet to be elucidated. In this TFPIFlox mice crossbred with Sma–Cre mice were utilized to establish TFPI conditional knockout mice and to examine the effects of VSMC-directed TFPI deletion on development, hemostasis, and thrombosis. The mice with deleted TFPI in VSMCs (TFPISma) reproduced viable offspring. Plasma TFPI concentration was reduced 7.2% in the TFPISma mice compared with TFPIFlox littermate controls. Plasma TFPI concentration was also detected in the TFPITie2 (mice deleted TFPI in endothelial cells and cells of hematopoietic origin) mice. Plasma TFPI concentration of the TFPITie2 mice was 80.4% lower (P<0.001) than that of the TFPIFlox mice. No difference in hemostatic measures (PT, APTT, and tail bleeding) was observed between TFPISma and TFPIFlox mice. However, TFPISma mice had increased ferric chloride–induced arterial thrombosis compared with TFPIFlox littermate controls. Taken together, these data indicated that endogenous TFPI from VSMCs inhibited ferric chloride–induced arterial thrombosis without causing hemostatic effects.

关键词: arterial thrombosis     conditional knockout mice     tissue factor pathway inhibitor     vascular smooth muscle cells    

A review of condition-based maintenance: Its prognostic and operational aspects

Yanrong LI, Shizhe PENG, Yanting LI, Wei JIANG

《工程管理前沿(英文)》 2020年 第7卷 第3期   页码 323-334 doi: 10.1007/s42524-020-0121-5

摘要: Condition-based maintenance (CBM) detects early signs of failure and dictates when maintenance should be performed based on the actual condition of a system. In this paper, we first review some of the recent research on CBM under various physical structures and signal data. Then, we summarize several kinds of prognostic models that use monitoring information to estimate the reliability of complex systems or products. Monitoring information also facilitates operational decisions in production planning, spare parts management, reliability improvement, and prognostics and health management. Finally, we suggest some research opportunities for the reliability and operations management communities to fill the research gap between these two fields.

关键词: condition-based maintenance     prognostics     operational decision-making     reliability    

Trend prediction technology of condition maintenance for large water injection units

Xiaoli XU, Sanpeng DENG

《机械工程前沿(英文)》 2010年 第5卷 第2期   页码 171-175 doi: 10.1007/s11465-009-0091-0

摘要: Trend prediction technology is the key technology to achieve condition-based maintenance of mechanical equipment. Large-sized water injection units are key equipment in oilfields. The traditional preventive maintenance is not economical and cannot completely avoid vicious accidents. To ensure the normal operation of units and save maintenance costs, trend prediction technology is studied to achieve condition-based maintenance for water injection units. The main methods of the technology are given, the trend prediction method based on neural network is put forward, and the expert system based on the knowledge is developed. The industrial site verification shows that the proposed trend prediction technology can reflect the operating condition trend change of the water injection units and provide technical means to achieve condition-based predictive maintenance.

关键词: water injection units     condition-based maintenance     trend prediction    

标题 作者 时间 类型 操作

Emerging roles of podoplanin in vascular development and homeostasis

null

期刊论文

Development and application of an off-site maintenance system in the petrochemical industry

Ruisheng YONG, Yanbing YE, Hanbin LUO, Lieyun DING

期刊论文

民航视情维修决策优化模型发展

张海军,左洪福,梁剑,戎翔

期刊论文

Lymphatic metastasis is related to the epithelial-mesenchymal transition and expressions of VEGF, MMP

Lihui WANG, Lianhong LI, Shen LV, Shujun FAN, Li ZHAN, Bo WANG, Zhong ZHANG

期刊论文

Endostatin specifically targets both tumor blood vessels and lymphatic vessels

Wei Zhuo, Yang Chen, Xiaomin Song, Yongzhang Luo

期刊论文

Risk evaluation for the task transfer of an aircraft maintenance program based on a multielement connection

期刊论文

Mechanism of vascular endothelial growth factor on the prevention of restenosis after angioplasty

Qigong LIU, Honglian ZHOU, Yan ZENG, Shan YE, Jiani LIU, Zaiying LU

期刊论文

Human reliability in maintenance task

Pacaiova HANA,

期刊论文

Crk-associated substrate, vascular smooth muscle and hypertension

TANG Dale

期刊论文

Role of nitric oxide in biological effects of vascular endothelial growth factor

Qigong LIU M D , Yan ZENG , Jiani LIU , Shan YE , Yongdong LI , Zaiying LU M D ,

期刊论文

Progress in tumor vascular normalization for anticancer therapy: challenges and perspectives

null

期刊论文

sulfate promotes the formation of atherosclerotic lesions and induces plaque instability by targeting vascular

null

期刊论文

Endogenous tissue factor pathway inhibitor in vascular smooth muscle cells inhibits arterial thrombosis

null

期刊论文

A review of condition-based maintenance: Its prognostic and operational aspects

Yanrong LI, Shizhe PENG, Yanting LI, Wei JIANG

期刊论文

Trend prediction technology of condition maintenance for large water injection units

Xiaoli XU, Sanpeng DENG

期刊论文