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The relationship between platelet-derived growth factor expression and angiogenesis/lymphangiogenesis in cervical cancer

Guocheng LIU MD, Shouhua YANG MD, Zehua WANG MD,

《医学前沿（英文）》 2009年第3卷第4期页码 447-451 doi: 10.1007/s11684-009-0082-x

摘要： This paper is aimed to examine if changes in platelet-derived growth factor (PDGF) expression at different stages of cervical cancer are related to the variation in blood vessel density (BVD) and lymphatic vessel density (LVD) to evaluate the relationship between PDGF expression and stages and metastasis of cervical cancer. Polymerase chain reaction (PCR) and RT-PCR were used to detect the expression levels of PDGF in 45 cervical cancer tissue samples (the experimental group). The samples were immunohistochemically stained with monoclonal antibodies D2-40 and CD34, and BVD and LVD were measured. The expressions of PDGF-A, -B, and- D were all higher in the experimental group than in the control group (<0.05); no significant difference was found in the expression of PDGF-C between the experimental group and the control group (>0.05). PDGF-A and -B expression was positively related with BVD and LVD (<0.01, R= 0.49, 0.527, 0.327, 0.68). The expression levels of PDGF-C and -D were not significantly related with BVD and LVD. At the early stage of cervical cancer, BVD and LVD were significantly higher than in the controls (<0.01). The BVD and LVD in tissues in the surrounding areas of cervical cancer were significantly higher than in tissues at cancer center, and LVD was related to lymph node metastasis (<0.001). BVD and LVD were not associated with the differentiation and pathological stages of cervical cancer. The expressions of PDGF-A, -B, and -D in cervical cancer were closely related with the clinical stages of cervical cancer. PDGF-A and -B were intimately associated with the lymph node metastasis and prognosis of cervical cancer.

关键词： cervical cancer lymphatic vessel density blood vessel density platelet-derived growth factor

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Bioaerosol: A Key Vessel between Environment and Health

《环境科学与工程前沿（英文）》 2021年第15卷第3期 doi: 10.1007/s11783-021-1422-6

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Probabilistic model for vessel-bridge collisions in the Three Gorges Reservoir

Bo GENG , Hong WANG , Junjie WANG ,

《结构与土木工程前沿（英文）》 2009年第3卷第3期页码 279-285 doi: 10.1007/s11709-009-0044-z

摘要： Based on a field observation on vessel transit path of three bridges over the Yangtze River in the Three Gorges Reservoir, and an analysis of the geometric probabilistic model of transiting vessels in collision probability calculation, the aberrancy angle and vessel velocity probabilistic model related with impact force, a probabilistic model is established and also verified by goodness-of-fit test. The vessel transit path distribution can be expressed by the normal distribution model. For the Three Gorges Reservoir, the mean and standard deviation adopt 0.2 and 0.1, respectively ( is the channel width). The aberrancy angle distribution of vessels accepts maximum I distribution model, and its distribution parameters can be taken as 0.314 and 4.354. The velocity distribution of up-bound and down-bound vessels can also be expressed by the normal distribution model.

关键词： vessel-bridge collision probabilistic model parameter statistics

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Construction of the vessel-collateral theory and its guidance for prevention and treatment of vasculopathy

Yiling Wu

《医学前沿（英文）》 2011年第5卷第2期页码 118-122 doi: 10.1007/s11684-011-0140-z

摘要： According to the self-discipline of traditional Chinese medicine, vessel-collateral theory was constructed systematically, which was important to improving prevention and treatment level of vasculopathy. The hypothesis of “homeostasis ( ), compensatory auto-adaptation ( ), regulation ( ) and equilibrium ( )” based on the “qi–yin-yang–five elements” coupled with the (nutrients)- (defense) theory, has become the core content of the vessel-collateral theory. Clinical and laboratory trials have been developed to further confirm the scientific connotations of the hypothesis, such as capsule, as the representative drugs of vessel collateral theory, showed good efficacy in protecting the vascular endothelium, stabilizing the vulnerable plaque and reducing the blood vessel spasm. “Sou, ti, shu, tong” was the characteristics of capsule in treating “microvascular damage” as the core mechanism of acute myocardial infarction, cerebral infarction and microvascular complications of diabetes. capsules in the treatment of arrhythmia have made integrated adjustment advantage. capsules have been made treating both manifestation and root cause of chronic heart failure. These research have improved prevention and treatment level of major vascular system diseases.

关键词： vessel-collateral theory vasculopathy prevention and treatment

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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

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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

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Application progress of lymphography in oncology

Yang YU, Jibin LIU, Lixue YIN

《医学前沿（英文）》 2009年第3卷第1期页码 13-19 doi: 10.1007/s11684-009-0016-7

摘要： Lymphography is often used for the diagnosis of lymphatic metastasis in oncology. Determination of lymphatic metastasis is extremely important for accurate cancer staging, which may directly guide the clinical therapeutic scheme. In recent years, the technology of lymphography has developed rapidly on the basis of traditional lymphography, with the appearance of computed tomography (CT) lymphography, nuclear magnetic resonance (MR) lymphography, contrast-enhanced lymphosonography, and so on; the diagnostic accuracy has also been improved. The imaging principles and methods of these various technologies of lymphography are reviewed in this paper, and their applications and significance in oncology are also discussed in detail.

关键词： lymphography lymphatic metastasis sentinel lymph node biopsy

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Establishment and drug sensitivity evaluation of murine ascites hepatocarcinoma cell line with high lymphatic

Hongying ZHANG, Jianwu TANG, Wenting ZHU, Chunxiu HU, Guowang XU

《医学前沿（英文）》 2009年第3卷第2期页码 119-129 doi: 10.1007/s11684-009-0022-9

摘要： In order to provide a sensitive cell line model for investigating the mechanisms underlying the lymphatic metastasis of tumors and the effect of medicine against cells, a new murine ascites hepatocarcinoma cell line with high lymphatic metastatic potential (Hca-P/L ) was established and the effect of curcumin on biological behavior of Hca-P/L was observed. Murine ascites hepatocarcinoma cell strain with low lymphatic metastatic potential (Hca-P) was subcutaneously inoculated into the medioventral line of a mouse 615 and the first generation of metastatic tumor cells of inguinal lymph node (Hca-P/L ) was obtained. Then, Hca-P/L was screened by the route of mouse foot pad subcutaneously → lymph node → scale-up culture → mouse foot pad subcutaneously for five times consecutively. The sensitivity of two murine ascites hepatocarcinoma cell lines (Hca-P and Hca-P/L ) and two anchorage-dependent human hepatocarcinoma cell lines (SMC7721 and HepG ) to curcumin were studied by use of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay after these cells had been pretreated by curcumin at the concentration of 15-240 μmol/L for 48 h. After pretreatment by curcumin at the maximum non-cytotoxic dose of 15 μmol/L , the effect of curcumin against cell proliferation of Hca-P and Hca-P/L was observed by inverted microscope, cell growth curve and cell population doubling time; the effects of curcumin on cell cycles of Hca-P/L and Hca-P were studied by flow cytometry (FCM). The results showed Hca-P/L spreading to the lymph nodes at multiple sites in mice was screened from Hca-P. The lymph node metastatic rate was 100%. Curcumin had significant growth inhibiting effect on both murine ascites and human hepatocarcinoma cell lines in a dose-dependent manner ( <0. 05). At concentrations of 30-120 μmol/L, curcumin had more inhibition on murine ascites hepatocarcinoma cell lines than on human anchorage-dependent hepatocarcinoma cell lines. At concentrations of 60-240 μmol/L, curcumin had more inhibition on Hca-P/L with (the 50% inhibitory concentration) IC of 51.48 μmol/L than on Hca-P with IC of 90.87 μmol/L. After pretreatment by curcumin at the maximum non-cytotoxic dose of 15 mol/L for 7 days, the proliferations of Hca-P/L and Hca-P were inhibited ( <0.05) in a time-dependent manner ( <0.01) and the population doubling time of Hca-P/L and Hca-P was prolonged ( <0.01), and curcumin had more inhibition on Hca-P/L than on Hca-P ( <0.05). After pretreatment by 15 μmol/L curcumin for 48 h, the morphous of Hca-P/L was influenced more seriously than that of Hca-P and the cell cycle was redistributed with Hca-P/L being blocked in the S phase and Hca-P in the S and G /M phases. Hca-P/L was validated to be more sensitive to curcumin than Hca-P. Hca-P/L is a novel sensitive cell line model for investigating the mechanisms underlying tumor lymphatic metastasis and the effect of the medicine against cells.

关键词： murine ascites hepatocarcinoma cell line metastasis curcumin drug sensitivity

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Cell carrier function of hollow-fiber membrane in rotating wall vessel bioreactor

SONG Kedong, LIU Tianqing, ZHAO Hu, LI Xiangqin, MA Xuehu, CUI Zhanfeng

《化学科学与工程前沿（英文）》 2008年第2卷第1期页码 34-39 doi: 10.1007/s11705-008-0022-3

摘要： Large-scale expansion of the osteoblasts of a Sprague-Dawley (SD) rat was studied in a rotating wall hollow-fiber membrane bioreactor (RWHMB) by using hollow-fiber membrane as the carrier. For the sake of contrast, cells were also expanded in a T-flask using a hollow-fiber membrane as carrier and in a rotating wall vessel bioreactor (RWVB) using a microcarrier. During the culture period, the cells were sampled every 12 h, and after 5 days, the cells were harvested and evaluated with scanning electron microscopy (SEM), hematoxylin-eosin (HE) staining and alkaline phosphatase (ALP) staining. Moreover, von-Kossa staining and Alizarin Red S staining were carried out for mineralized nodules formation. The results show that in RWHMB, the cells present better morphology and vitality and secrete much more extracellular matrix. It is concluded that the RWHMB combines the advantages of the rotating wall vessel and hollow-fiber membrane bioreactors. The hydrodynamic stimulation within it accelerates the metabolism of the osteoblast and mass transfer, which is propitious to cell differentiation and proliferation.

关键词： RWHMB microcarrier hematoxylin-eosin von-Kossa staining propitious

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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

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Effect of current density on groundwater arsenite removal performance using air cathode electrocoagulation

《环境科学与工程前沿（英文）》 2021年第15卷第6期 doi: 10.1007/s11783-021-1399-1

摘要：

• With the same charge, current density had little effect on As(III) removal in ACEC.

关键词： Electrocoagulation Air cathode Arsenic Current density Energy consumption

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Effects of exercise therapy on bone mineral density in early postmenopausal women: a controlled trial

Shilin DENG MD ,

《医学前沿（英文）》 2009年第3卷第3期页码 323-329 doi: 10.1007/s11684-009-0061-2

摘要： The purpose of this article is to determine the effect of a well-designed combined aerobic, resistance, and extension exercise program on bone mineral density (BMD) in postmenopausal women. The population comprised 45 postmenopausal women, who exercised over 12months (exercise group), and 36 women who served as a non-training control group. BMD of the hip, and lumbar spine was measured at the baseline and 12th month. Repeated measurement analysis of variance and nonparametric test were utilized to compare differences between the exercise group and controls. Thirty-six out of 45 persons in the exercise group and 36 controls completed the study. Average compliance was 82.2% for the whole exercise group at the 12th month. All the subjects had decreased BMD, but the rate of bone loss was lower in the exercise group than in the control group at the L4 and hip. Although the exercise program in this study may probably reduce the rate of bone loss in weight-bearing skeletal sites, we do not suggest the exercise by itself be viewed as prevention or treatment for osteoporosis. Further, the exact dose-response relationship of exercise and bone mass in early postmenopause is not clear.

关键词： early postmenopausal women bone mineral density exercise effects

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density measurement for plastic injection molding via ultrasonic technology

《机械工程前沿（英文）》 2022年第17卷第4期 doi: 10.1007/s11465-022-0714-2

摘要： Density variation during the injection molding process directly reflects the state of plastic melt and contains valuable information for process monitoring and optimization. Therefore, in-situ density measurement is of great interest and has significant application value. The existing methods, such as pressure−volume−temperature (PVT) method, have the shortages of time-delay and high cost of sensors. This study is the first to propose an in-situ density measurement method using ultrasonic technology. The analyses of the time-domain and frequency-domain signals are combined in the proposed method. The ultrasonic velocity is obtained from the time-domain signals, and the acoustic impedance is computed through a full-spectral analysis of the frequency-domain signals. Experiments with different process conditions are conducted, including different melt temperature, injection speed, material, and mold structure. Results show that the proposed method has good agreement with the PVT method. The proposed method has the advantages of in-situ measurement, non-destructive, high accuracy, low cost, and is of great application value for the injection molding industry.

关键词： ultrasonic measurement melt density in-situ measurement injection molding

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中国开创的抗爆钢复合材料压力容器技术

朱国辉

《中国工程科学》 2000年第2卷第6期页码 8-11

摘要：

压力容器是一种应用广泛的重要工程装置。大型压力贮罐、氨合成塔、尿素合成塔、石油加氢反应器、导弹壳体和液氢、液氧燃料压力容器，以及核堆压力壳等是国际上公认的高科技重大承压装备。纤维复合材料和普通钢制是当今世界压力容器技术的两大种类。作者开创了一种新的具有优良综合特性，已含国家发明奖励和18项中美专利成果的抗爆钢复合材料压力容器技术，使压力容器的使用安全性和制造经济性发生了极大的变革；其典型代表钢带缠绕式压力容器，已被美国机械工程师学会正式列入ASME标准，居国际领先水平，将为21世纪国际压力容器的设计、制造和安全保障技术的发展开创出新的局面。

关键词：压力容器技术纤维复合材料钢复合材料复合薄内筒交错缠绕全双层结构抑爆抗爆

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Relationship of adrenomedullin expression and microvessel density and prognosis in smooth muscle tumor

JIANG Yuan, TIAN Xuehong, YUAN Jie, JIN Yuemei, TAN Yusong

《医学前沿（英文）》 2007年第1卷第4期页码 398-400 doi: 10.1007/s11684-007-0077-4

摘要： The aim of this paper was to investigate the relationship between the expression of adrenomedullin (ADM) and microvessel density (MVD) and prognosis in smooth muscle tumor of uterus. The expression of ADM was detected using immunohistochemical staining in specimens from 15 normal controls, 28 cases of uterine leiomyoma (LE) and 19 cases of uterine leiomyosarcoma (LES). The MVD was assayed by immunostainting with CD. There was a positive correlation between the ADM expression and MVD in LE and LES respectively ( = 0.823, <0.01; = 0.793, <0.01). The expression of ADM in LE was statistically lower than that in LES (<0.05). There was a positive correlation between the ADM expression and mitotic figures in LES (<0.05): the more mitotic figures, the higher levels of the ADM expression and poor prognosis. The ADM is an important angiogenic factor in smooth muscle tumor of uterus. The ADM can be used as an accessory marker in estimating the malignant potency of LE and judging the pro gnosis of LES, and as a novel molecular target of anti-angiogenic and anticarcinogenic strategies.

关键词： anticarcinogenic microvessel density malignant potency muscle uterine leiomyosarcoma