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1.
Basic fibroblast growthfactor (bFGF) is a multi-potential growth factor whose biological activities depend on its receptor’s intrinsic tyrosine kinase activity and second messengers such as the mitogen activated protein kinases. Heparin sulfate proteoglycans (HSPGs) have been demonstrated to enhance or inhibit bFGF activity. The response elicited by HSPGis related to the relative concentrations and binding kinetics for bFGF of the various pools of HSPG. The type of cellular response might depend on the specific HSPG and FGF receptor expressed on the cell surface. The specific core protein of HSPG, and tissue-specific differences in heparin sulfate modification result in altered bFGF regulation.  相似文献   

2.
AIM: To determine whether the eukaryotic initiation factor-4E (eIF-4E) inhibition facilitates the degradation of heparanase mRNA and alters heparanase protein expression in human colon adenocarcinoma cell line, LS-174T. METHODS: A 20-mer antisense s-oligodeoxynucleotide (asODN) targeted against the translation start site of eIF-4E mRNA were introduced into LS-174T cells by lipid-mediated DNA-transfection. eIF-4E protein and mRNA levels were detected by Western blot and RT-PCR, respectively. The mRNA levels of heparanase were determined by Northern blot. The alterations of heparanase expression were confirmed by Western blot analysis. RESULTS: The 20-mer asODN against eIF-4E specifically and significantly inhibited eIF-4E protein expression. Following eIF-4E inhibition, a significant reduction of heparanase mRNA was observed on Northern blot, and at the same time, heparanase protein expression significantly decreased as well. CONCLUSIONS: The results indicate that the inhibition of eIF-4E strongly reduces the stability of heparanase mRNA in colon adenocarcinoma cell line, LS-174T and resultes in an apparent reduction in the expression of heparanase protein.  相似文献   

3.
AIM: To evaluate the effects of hypoxia on the expression of heparanase and the invasiveness of SKOV3 ovarial carcinoma cell line. METHODS: SKOV3 cells were incubated at either normoxia (37 ℃, 5%CO2, 21%O2) or hypoxia (37 ℃, 5%CO2, 1%O2) condition for 12 h, 24 h and 36 h. RT-PCR and Western blotting were used to detect mRNA and the protein expressions of heparanase under different conditions. Cell invasiveness was measured by matrigel invasion assay. RESULTS: Compared to normoxia group, the heparanase mRNA expression level in hypoxia group was increased and in 12 h hypoxia group was the highest. The heparanase protein expression in hypoxia group was also significantly increased (P<0.01) and the expression of heparanase in hypoxia group was also different (P<0.05). Compared to normoxia group, the level of cell invasion was markedly increased in 12 h, 24 h and 36 h groups (P<0.05). During 12-36 h hypoxia period, the increase in hypoxia-induced invasiveness in SKOV3 cell line showed a time-dependent manner (P<0.05). Meanwhile, there was a positive correlation between the expression of HPA and the invasiveness of SKOV3 cells (r=0.8530, P<0.05). CONCLUSION: Invasion of SKOV3 cells in hypoxia condition correlates with heparanase level. Hypoxia plays an important role in the augmentation of the heparanase expression and the invasiveness of human ovarian cancer.  相似文献   

4.
AIM: To investigate the differential expression of serum proteins in cirrhotic SD rats for exploring the pathogenesis and identifying the potential biomarkers of radiation-induced hepatic injury. METHODS: Liver cirrhosis was induced in 8 healthy SD rats with subcutaneous injection of carbon tetrachloride (CCl4) for 6 weeks and then the animals were randomly divided into 2 groups (4 rats in each group): control group (CCl4 alone) and experimental group (CCl4 plus radiation). The latter received hemi-liver radiation with single dose of 15 Gy while the former did not receive radiation. Total serum proteins of the 2 groups were extracted 6 h after radiation. Two-dimensional gel electrophoresis (2-DE) were performed to look for differentially expressed proteins. These proteins were then analyzed and identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS). Western bloltting was used to validate the expression of heparanase and hepatocyte growth factor receptor in all independent series of serum samples. RESULTS: Two-dimensional gel images were acquired with good resolution and repetition. Thirty-three differentially expressed proteins were selected and 12 proteins were successfully identified by MS, in which 5 were up-regulated while 7 were down-regulated. The increased level of heparanase and decreased level of hepatocyte growth factor receptor were further confirmed by Western blotting. CONCLUSION: Twelve proteins associated with radiation-induced hepatic injury are successfully characterized by serum comparative proteomics. Heparanase and hepatocyte growth factor receptor might be useful for detecting and monitoring radiation-induced hepatic injury.  相似文献   

5.

Background  

Aliphatic molecules containing free carboxyl groups are important intermediates in many metabolic and signalling reactions, however, they accumulate to low levels in tissues and are not efficiently ionized by electrospray ionization (ESI) compared to more polar substances. Quantification of aliphatic molecules becomes therefore difficult when small amounts of tissue are available for analysis. Traditional methods for analysis of these molecules require purification or enrichment steps, which are onerous when multiple samples need to be analyzed. In contrast to aliphatic molecules, more polar substances containing free carboxyl groups such as some phytohormones are efficiently ionized by ESI and suitable for analysis by LC-MS/MS. Thus, the development of a method with which aliphatic and polar molecules -which their unmodified forms differ dramatically in their efficiencies of ionization by ESI- can be simultaneously detected with similar sensitivities would substantially simplify the analysis of complex biological matrices.  相似文献   

6.
The cytokine-receptor- heparin sulfate functional complex combined by cytokines, cytokine receptors, and heparin sulfate chains formed by concatenation of heparin sulfate proteoglycans (HSPG), an important component of extracellular matrix and modified by some relative enzymes, can regulate the density of cytokine receptors and their intracellular signal transduction. This article focused on the regulatory function of this complex. Many morphological abnormalities and diseases occur when the complex is dysfunctional.  相似文献   

7.
Lü Jie  LI Min-min 《园艺学报》2020,36(2):378-384
Exosomes are extracellular vesicles that are actively released from all types of cells to various body fluids under the physiological and pathological conditions. It can be used as an intercellular signaling carrier by transferring specific components such as proteins, lipids and nucleic acids, which mediates the transmission of information between cells, thereby affecting the biological function of the recipient cells. Urinary exosomes are secreted by various cells in the urinary system and released into the urine. Recent studies have shown that changes of urinary exosome microRNAs can be used as biomarkers in kidney diseases for monitoring the changes of diseases and judging prognosis, and also have important value in the disease treatment. This article reviews the progress of urinary exosome microRNAs in kidney diseases.  相似文献   

8.
The dynamics of plant cover and land use types in three study areas - Keava (1192.05 ha), Meenikonna (1513.35 ha) and Nätsi-Võlla (888.61 ha) mire landscapes, each divided into natural (N) and anthropogenous (A) subareas, was investigated by repeated aerial photo (black-and-white panchromatic, 1:10,000) interpretation. Nineteen plant cover and land use (PC&LU) types were differentiated and three contour maps were drawn for each study area (corresponding to 1950's, 1960's and 1980's).The dynamics of mire landscapes were modelled by transition matrices P = [Pij], which contain the transition probabilities between i-th and j-th PC&LU types during the time interval between the aerial photographs. A total of 12 transition matrices were constructed.In A-subareas peat milling was started in the middle of the 60's whereas N-subareas acquired mire reserve status in 1981, which is manifested in a different development. 93% of N-subarea and 69% of the A-subarea remained unchanged from the 50's to the 80's. The increase of anthropogenous land use types in A-subareas of Keava, Meenikonna and Nätsi-Võlla were respectively 0.84%, 0.32% and 1.17% per year.Two different matrices (I and II period) were used to predict the future state of the study areas. The applicability of the transition matrix model has been discussed by comparing matrices of different base periods. Errors arising from photointerpretation, contour input, (transition) area measurement, matrix reduction etc. are evaluated.  相似文献   

9.
AIM: To observe the effects of insulin-like growth factorⅡ (IGF-Ⅱ) at different expression levels on hepatocellular carcinoma Huh7 cell proliferation and migration, and to explore the role of IGF-Ⅱ in the development of HCC. METHODS: The Huh7 cells were transfected with the over-expression plasmid pcDNA3.1(+)- IGF-Ⅱ or RNA interference plasmid pLVX-shRNA-IGF-Ⅱ by Lipofectamine 2000. The quantitative real-time PCR and Western blotting were used to verify the expression of IGF-II. The biological behaviors of the Huh7 cells were analyzed by CCK-8 assay, plate clone formation assay, cell scratch test and Transwell chamber experiment.RESULTS: Over-expression of IGF-II promoted the growth and migration of hepatocellular carcinoma cells (P < 0.05), and the cell proliferation was significantly inhibited in the Huh7 cells with low IGF-II expression (P < 0.05).CONCLUSION: IGF-II is involved in the regulation of biological behavior of hepatocellular carcinoma Huh7 cells in vitro, which may play a promoting role in the development of hepatocellular carcinoma.  相似文献   

10.
AIM: Secretogranin III (SCG3/Sg III) is extensively distributed in endocrine or endocrine-like cells in human body and plays an important role in some biological functions by regulating peptide hormone secretion and neuroendocrine activity.The distribution and functions of SCG3 make itself as not only one of the most useful biological markers in association with neuroendocrine functions, but also a potential indicator of diagnostic and prognostic evaluation in certain diseases.The gene and protein structures, tissue expression, biological functions as well as pathophysiology and clinical significance of SCG3 are reviewed in this article.  相似文献   

11.
12.
Lymphocyte-derived microparticles (LMPs) are small membrane vesicles that are released upon activation or during apoptosis from lymphocytes.The LMPs were detected at elevated levels in the patients with inflammatory diseases, cardiovascular diseases or diabetes. In addition, LMPs are important mediators of transferring biological information and switching on the biological effects through their interaction with the target cells. Moreover, LMPs play completely distinct roles in different physiological and pathological conditions. This article describes the possible mechanism involved in the formation, composition, key biological activities and the relationship with diseases.  相似文献   

13.
Endothelial-mesenchymal transition (EndMT) is a biological process through which endothelial cells change their endothelial phenotype into a mesenchymal or myofibroblastic phenotype with the expression of mesenchymal markers such as α-smooth muscle actin (α-SMA) and vimentin. When the pulmonary vascular endothelial cells are exposed to hypoxia and inflammatory stimulation, vascular smooth muscle cells in the outer and middle membrane accumulate through EndMT process, leading to pulmonary vascular remodeling and pulmonary arterial hypertension (PAH). Transforming growth factor β (TGF-β)/bone morphogentic protein (BMP) signaling pathways promote EndMT process by bone morphogentic protein receptor 2 (BMPR2) gene mutation which up-regulates high mobility group protein A1 (HMGA1) gene and contributes to protein expression such as Slug and Snail, thus resulting in PAH. In brief, TGF-β/BMP signaling pathways and related regulators play an important role in pulmonary vascular reconstruction and the formation of PAH.  相似文献   

14.
Transition matrices have often been used in landscape ecology and GIS studies of land-use to quantitatively estimate the rate of change. When transition matrices for different observation periods are compared, the observation intervals often differ because satellite images or photographs of the research site taken at constant time intervals may not be available. If the observation intervals differ, the transition probabilities cannot be compared without calculating a transition matrix with the normalized observation interval. For such calculation, several previous studies have utilized a linear algebra formula of the power root of matrices. However, three difficulties may arise when applying this formula to a practical dataset from photographs of a research site. We examined the first difficulty, namely that plural solutions could exist for a yearly transition matrix, which implies that there could be multiple scenarios for the same transition in land-use change. Using data for the Abukuma Mountains in Japan and the Selva el Ocote Biosphere Reserve in Mexico, we then looked at the second difficulty, in which we may obtain no positive Markovian matrix and only a matrix partially consisting of negative numbers. We propose a way to calibrate a matrix with some negative transition elements and to estimate the prediction error. Finally, we discuss the third difficulty that arises when a new land-use category appears at the end of the observation period and how to solve it. We developed a computer program to calculate and calibrate the yearly matrices and to estimate the prediction error.  相似文献   

15.
AIM:To investigate the biological characteristics of newborn rabbit tracheal chondrocytes in vitro. METHODS:Newborn rabbit tracheal chondrocytes were obtained by the method of enzyme digestion, and then cultured in monolayer in vitro. Morphological and growth observations were performed under inverted phase contrast microscope. The ultrastructures of the cells were observed under scanning electron microscope and transmission electron microscope. The biological characteristics of secreted extracellular matrix components were detected by real-time PCR, immunocytochemistry staining and toluidine blue staining. RESULTS:Newborn rabbit tracheal chondrocytes isolated and cultured in vitro showed short triangular or irregular shapes, and adherent growth very well. The ultrastructures of the cells showed pore and abundant cytoplasm and organelles, with a lot of protein secretions in the cells. The chondrocytes expressed the mRNA of collagen I, collagen II and proteoglycans, mainly collagen II and proteoglycans. Immunocytochemistry staining showed collagen II and SOX9 positive, and collagen I weakly positive. Toluidine blue staining was also positive. CONCLUSION:Enzyme digestion and monolayer culture are suitable method to obtain newborn rabbit tracheal chondrocytes. These cells, secreting extracellular matrix components, are able to be selected as seed cells for tissue engineering of trachea in vitro, and used to study the therapeutic method for neonatal rabbit tracheal stenosis.  相似文献   

16.
AIM: To explore interaction and biological behaviour changes of two kinds of cells-blastocysts and hepatocarcinoma cells in the same microenvironment. METHODS:The models of mouse blastocysts co-cultured with human hepatocarcinoma cell lines were established, then biological behaviours and mutual effects of the two kinds of cells in co-culture system were observed. RESULTS: Compared with control group, hepatocarcinoma cells with differently invasive and metastatic potential significantly enhanced the rates of blastocyst hatchment , attachment and outgrowth(P<0.05). There was no significant difference in those among hepatocarcinoma cells co-cultured groups (P>0.05). The blastocyst hatched and attached to hepatocarcinoma cells with differently invasive and metastatic potential. Then, differential trophoblasts invaded hepatocarcinoma cells. The clear-cut interfaces were gradually formed between both sides. Hepatocarcinoma cells on interface showed changes of growth direction and cell shapes and did not invade blastocysts. CONCLUSIONS: Hepatocarcinoma cells promoted blastocyst development. Blastocysts implanted and invaded hepatocarcinoma cells with differently invasive and metastatic potential in vitro, which indicate that blastocyst implantation in vitro does not relate with the kinds and differential level of interactional cells and the low selectivity maybe relate with high adaptability of early life.  相似文献   

17.
以河砂、泥炭土、珍珠岩、菌渣、黄壤土、树皮等常用盆栽基质为试验材料,研究6种基质在干燥、湿润条件下对自制甲醛熏气箱中甲醛气体的吸收效果,分析密封箱内甲醛浓度随时间的变化关系.结果表明:珍珠岩、泥炭土、河砂、菌渣、黄壤土对甲醛有较好的吸收作用,基质6 h吸收甲醛能力排序为:珍珠岩>泥炭土>河砂>黄壤土>菌渣>树皮;湿润基质比干燥基质的吸收效果好,基质含水量对甲醛吸收有一定的作用;基质吸收甲醛经历“显著-有效-饱和”的变化过程  相似文献   

18.
AIM:To study the effect of p19ARF on the biological behavior of human leukemia cells. METHODS:p19ARF was cloned in eukaryotic expression vector pcDNA3.1 and transferred into INK4a/ARF locus-deficient leukemia cells HEL and K562. The changes in biological characteristics of the two p19ARF-transfected cells were observed.RESULTS:The growth of the p19ARF-transfected HEL cells was significantly inhibited compared with the vector-transfected cells; Cell cycle analysis showed that the expression of foreign p19ARF gene resulted in G1 phase cell cycle arrest and apoptosis cell death in some of HEL cells. However, p19ARF had no marked effects on the growth of K562 cells with p53 gene mutation and did not induce apoptosis in K562 cells.CONCLUSION:p19ARF suppressed the growth of leukemia cells by p53-dependent pathway.  相似文献   

19.
QI Rui-juan  GAO Yuan  QI Yun 《园艺学报》2021,37(1):151-158
Mast cells are important cells for the innate immunity that reside in tissues including adipose tissue and are involved in various physiological and pathological processes by producing a range of biological mediators. Adipose tissue not only acts as an energy depot and regulator of energy homeostasis that can deposit excess energy and dissipate energy through heat, but also is an active endocrine organ capable of producing hormones and adipokines. The dysfunction of adipose tissue is highly correlated with metabolic disorders, such as obesity, type 2 diabetes mellitus and so on. This review focuses on the physiological and pathological roles of mast cells in adipose tissue.  相似文献   

20.
AIM: To define the gene expression changes of vascular smooth muscle cells (VSMCs) in response to norepinephrine (NE). METHODS: The expression adrenergic receptors (AR) were determined by radioligand binding assay in A7r5 cells. Gene expression profiles were identified by cDNA microarray after A7r5 cells were treated with NE for 24 h, and mRNA expressions of α1A-AR and α1B-AR were confirmed by real-time PCR. RESULTS: α1-AR and β-AR existed in A7r5 cells. Seventy-five genes with changed expression in response to NE were screened out. These genes are involved in cell structure, cell/organism defense, metabolism, signal transduction and so on. α1A-, α1B-AR mRNA expression identified by microarray and realtime quantitive PCR displayed similar patterns. CONCLUSIONS: Gene expression profile in response to NE was analyzed comprehensively with the microarray technique. NE induces many kinds of different function genes in A7r5 cells, which may provide a novel insight into the particular role of NE that modulates multiple aspects of biological function in VSMCs.  相似文献   

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