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1.
The invasion of cytotrophoblast cells into the maternal endometrium during embryonic implantation is very similar to the metastasis of carcinoma cells. However, the significant difference is that the former is a highly controlled process. In this report, the effects of integrin αvβ3 on the secretion of matrix metalloproteinase (MMP) were compared between normal cytotrophoblast cells and choriocarcinoma cells by RT-PCR, gelatin zymography and immunocytochemistry. The results reveal that both normal cytotrophoblast cells and choriocarcinoma cells can express integrin αvβ3. The secretion of MMPs in normal cytotrophoblast ceils is up-regulated by anti-αvβ3 antibody, whereas, decreased in choriocarcinoma cells. It was suggested that αvβ3 can modulate the expression of MMPs in trophoblasts, and this action is carried out through distinct mechanisms in normal and carcinoma cytotrophoblast cells.  相似文献   

2.
The polycarbohydrate structure of Galα1- 3Ga1β1-4GluNAc-R (known as αGal epitopes of xenoantigen), produced by α1-3-galactosyltransferase (α1,3-GT) in the course of animal development, is the major xenoantigen on the cell surface of porcine which causes hyperacute rejection in pig-to-human xenotransplantation. Alpha-1,3-galactosidase (AGL), a hydrolytic enzyme, can remove the terminal α1,3-galactosyi from the Galα1-3Galβ1-4GluNAc-R structure resulting in cleaning αGai epitopes from the porcine cells. Aipha-1,2-fucosyitransferase (HT) can modify the surface carbohydrate phenotype of porcine cells, bringing about reduction of αGai epitopes expression. In this study, human AGL and HT gene were co-transfected to porcine fetal fibroblast (PFFb) in equimolar concentration to reduce the xenoantigen. Gene and protein of hAGL and HT were both detected to express at high level by RT-PCR and Western blot, respectively. There was an 84% reduction in αGai xenoantigen and an 82% increase in H antigen as assayed by flow cytometry in the AGL and HT gene co-transfected PFFb. The number and morphology of transgenic PFFb chromosome were normal. Findings indicate that Galα1-3Gal epitopes of PFFb could be down regulated by AGL and HT co-transfection without deleterious effects on the chromosomal profile of the transgenic ceil.  相似文献   

3.
The relation between microwave conductivity and normal conductivity of solution is compared in this thesis. By building mathematical model and theoretical analyses, it indicates that the relationship of in situ conductivity of solution in microwave field and temperature is similar to that in non-microwave field. It can be expressed by quadratic equation but the values of both conductivities are different. Microwave field has effect on the mean path δ or hot vibrational frequency v of ions in solution. In microwave field, the mean energy barrier, which ions must surmount as they transit, is the function relation to temperature.  相似文献   

4.
The serological and biochemical characterization of porcine red blood cells (pRBCs) are similar to human red blood cells,Porcine erythrocytes are considered as an alternative source for human blood transfusion.But there exist galactose-α1,3-galactose antigens (Galα1,3Galβ1,4galNAc-R,abbreviated αGal antigen ) on pRBCs,which can induce anti-αGai antibodies in human serum ,The αGal epitopes are the major antigen responsible for hyperacute rejection in exnotransfusion .In this study ,recombined soybean α-galactosidase (rSα-GalE) was used to remove the αGal antigens from pPRCs for humanization .The results showed that αGal antigen was eleared by rSα-GalE and the structure and function of rSα-GalE treated pRBC were normal.  相似文献   

5.
Study on the Universality of the Normal Cloud Model   总被引:6,自引:0,他引:6  
The distribution function is an important tool in the study of the stochastic variances. The normal distribution is very popular in the nature and our society. The idea of membership functions is the foundation of the fuzzy sets theory. While the fuzzy theory is widely used, the completely certain membership function that has no any fuzziness at all has been the bottleneck of the applications of this theory.Cloud models are the effective tools in transforming between qualitative concepts and their quantitative expressions. It can represent the fuzziness and randomness and their relations of uncertain concepts. Also cloud models can show the concept granularity in multi-scale spaces by the digital characteristic Entropy (En). The normal cloud model not only broadens the form conditions of the normal distribution but also makes the normal membership function be the expectation of the random membership degree. In this paper, the universality of the normal cloud model is proved, which is more superior and easier, and can fit the fuzziness and gentleness of human cognitive processing.It would be more applicable and universal in the representation of uncertain notions.  相似文献   

6.
Trichosanthin (TCS) is a plant toxin with ribosome-inactivating activity. TCS can be internalized by the host cells and then attacks the ribosomes resulting in cell death. However, the manner for endocytic uptake of TCS is not well understood. The present work investigates the endocytosis pathway of TCS in human choriocarcinoma cells. The different endocytic mechanisms are interfered by potassium depletion, cholesterol-extraction/addition, or treatments of various drugs. The experiments detect their effects on the TCS-uptake. The results show that a large portion of the TCS can be internalized by clathrin-dependent, as well as by clathrin-independent but cholesterol-dependent endocytosis in human choriocarcinoma cells.  相似文献   

7.
Mesenchymal stem cells (MSCs) are multipotent cells, which can differentiate into different tissues. It is still controversial whether MSCs can be isolated from adult peripheral blood (PB) under normal conditions and whether they can be mobilized in a way similar to that of hematopoieUc stem cells (HSCs). In this study, rat MSCs circulating in the PB under normal conditions can be isolated and cultured, and MSCs from PB and BM can be mobilized by LiCL. The mobilized MSCs can be induced to differentiate into neuron by such factors as β-mercaptoethanol and supernatants of nerve cell cultures. The present study provides a broader perspective on the repair of neural trauma.  相似文献   

8.
A previous study indicated that C–C chemokine(C–C motif)ligand 18(CCL18)is capable of inducing tumor cell invasion and metastasis by interacting with receptor membrane-associated phosphatidylinositol transfer protein 3(PITPNM3)in breast cancer cells.The present study aims to investigate the correlation between the PITPNM3 expression and metastasis in hepatocellular carcinoma(HCC).Real-time quantitative polymerase chain reaction and Western blot were performed to detect the expression pattern of PITPNM3 in patient samples and HCC cell lines.Wound-healing and transwell chamber assays were performed to assess the migration and invasiveness of HCC cells,and the activation of the signaling protein downstream of PITPNM3 was also detected by Western blot and immunofluorescence.The results revealed that PITPNM3 was upregulated in HCC tissue compared to matched normal liver tissue.Silencing the expression of PITPNM3 by specific siRNAs markedly attenuated the invasive and metastatic abilities of HCC cells,whereas the upregulation of PITPNM3 significantly increased HCC cell mobility.Furthermore,inhibiting the expression of PITPNM3 suppressed the activation of Pyk2,FAK,and Src,while overexpression of PITPNM3enhanced the phosphorylation of FAK and Src in HCC cells.Besides,suppression of Pyk2 can also impair the clustering of integrin.These results imply that PITPNM3 is a vital determinant of HCC migration and invasion.  相似文献   

9.
The effects of nerve regeneration factor (NRF) on neuronal differentiation of PC12 cells and its signaling pathway are investigated by morphological observation and immunofluorescent cytochemical method, and the activity of ERK1/2 in NRF-treated PC12 cells in absence of serum is also studied by immuno-coprecipitation and Western blot analysis. The MEK1/2-specific inhibitor U0126, the broad-spectrum protein kinase C (PKC) inhibitor G?6983 and tyrosine protein kinase (TPK) inhibitor genistein were used to determine the roles of the activation of ERK1/2 by NRF and the involvement of certain kinds of PKC or TPK receptor in this activation process. The results show that U0126 and G?6983 inhibit the activation of ERK1/2 by NRF to different extents, while genistein has no effect on it, demonstrating that NRF remarkably induces neuronal differentiation of PC12 cells through activating ERK1/2 in a dose-dependent and time-dependent manner.  相似文献   

10.
The difference between human normal and carcinoma lung cells was studied with regard to the protein expression level and localization of the cadherin/catenin/actin complex. Results demonstrated that normal lung cell RF expressed high levels of N-cadherin, β-catenin, α-catenin. These 3 proteins were colocalized at AJs and their submembrane adhesion plaques where they link the Rho-phalloidin-positive actin stress fibers, indicating the existence of N-cadherin/catenin/actin complexes at the AJs. Aberrant expression of AJ proteins and the actin cytoskelecton in carcinoma PG cells was observed: (1) inhibition of N-cadherin and to a degree of inhibition of α-catenin protein expression; (2) varied protein modification of β-catenin in cytoplasm soluble fraction and altered distribution of immunofluorescence: majorly in the cytoplasm and minorly on the membrane; (3) disassembly of actin stress fibers and formation of actin bodies in the cytoplasm. The data suggest that inhibited expression of AJ proteins is correlated with the disruption of the AJ complexes and the actin cytoskeleton in carcinoma PG cells, and responsible for its metastasis behaviors.  相似文献   

11.
12.
The target molecule of monoclonal antibody AA98 (AA for short) is a new vascular endothelial cell related factor and plays a role in angiogenesis as indicated by the previous data. To investigate its role in angiogenesis and placentation in primate, we examined its expression in the implantation sites on D17, 19, 28 and 34 of gestation in rhesus monkey by immunohistochemistry and Western immunoblot. Western blot analysis showed that the primary antibody used in this study was specific for its epitope. AA protein was mainly expressed in small blood vessels and in some cytotrophoblast cells. The AA staining was found mainly in the endothelial cells and vascular small muscle. This observation supported the AA‘s role in angiogenesis. AA was spatio-temporarily expressed in cytotrophoblasts: weak in proliferating trophoblast within cell column and endovascular trophoblast, strong in trophoblastic subpopulation within the basal plate and vascular trophoblast; AA staining within the basal plate was down-regulated during early placentation. The shift of AA98 expression in extravillous trophoblasts suggestes a role of this new factor during the course of cytotrophoblast metastasis and spiral artery remodeling. The spatio-temporarily expression indicats that AA98 could be also used as a trophoblast cellular marker to characterize the acquisition of a vascular endothelial and invasive phenotype.  相似文献   

13.
Using histological and histochemical methods the structure of the endostyle in amphioxus at different gonadal developmental stages is studied, and the immunocytochemical localization of thyroglobulin (Tg) and thyrotropin (TSH) in the endostyle, Hatschek's pit and brain vesicle is investigated. The results not only confirm the previous report that the endostyle is composed of 6 zones and the cells of zone 5 are thyroid hormone synthesizing cells, but also find the thyroxine synthesis in and secretion from zone 3. In addition, the epithelial cells in Hatschek's pit and the neural cells in brain vesicle are immunopositive for TSH, and the immunoactivity is correlated with gonadal cycle. The present study may provide morphological proof for the hypothesis that the secretory activity of thyroid cells is regulated by TSH from Hatschek's pit and brain vesicle.  相似文献   

14.
The study and the practical utilization of the infrared inthe textile field is analysed simply.The test method ofthe infrared transmittance(α_T)and the reflectance(α_R)in the fabric is introduced.The test results of aset of polyester/cotton plain fabrlcs show that the infra-red reflecting regulation can be expressed by quasi-co-sine function.The parameters affecting the α_T and α_Rare analysed, α_T decreases according to negative expo-nent function as the weight per square meter of the fab-ric increases,and α_R increases.Both α_T and α_R will in-crease when the mode of wavelength(λ_m) of the infra-red decreases.It can be deduced that the infrared ab-sorptance of the fabric will increase as λ_m increases inthe studied range.  相似文献   

15.
In order to understand the role of Le+Y oligosaccharide antigen (Le+Y) during implantation, the relationship of Le+Y on the cell surface with matrix metalloproteinase (MMPs) secreted by blastocysts and monolayer epithelial cells during implantation in the mouse %in vitro% was studied by monoclonal antibody (mAb) AH-6, directed to Le+Y[Fuc α1-2 Gal β1-4 (Fuc α1-3) GlcNAc-], and gelatin zymography. The results showed that MMPs secretion was reduced after Le+Y on the cell surface of either epithelial cells or trophoblasts was blocked. It indicated that MMPs expression which played an important function during the process of implantation were regulated by Le+Y. Therefore, it was considered that Le+Y could regulate embryos invasion by some mechanism.  相似文献   

16.
When used in combination with certain chemotherapies, curcumin has been shown to increase apoptosis in several cancer cell lines. Here, we report the combined effects of curcumin and cinobufacini on human cervical carcinoma cells. The aim of this study was to examine whether curcumin could enhance apoptosis induced by cinobufacini. 3-(4,5-Dimethylthiazol-2-y1)-2,5- diphenytetrazolium bromide (MTT) assays revealed that the growth and proliferation of HeLa cells could be inhibited by 75% after a combined treatment of 25 μg/mL cinobufacini and 8 μg/mL curcumin. The combined treatment is 3 times more effective than treatment with 25 μg/mL cinobufacini alone. Annexin V-FITC/PI staining, morphological changes and immunofluorescence verified a significant enhancement in cinobufacini-induced apoptosis when cells were also exposed to curcumin. The data showed that the proportion of early apoptotic cells significantly increased from 15.43% in cells treated only with 25 μg/mL cinobufacini to 49.2% in cells treated with 25 μg/mL cinobufacini and 8 μg/mL curcumin. Moreover, compared with treatment of only 25 μg/mL cinobufacini, ROS production increased 1.7-fold, the intracellular free Ca 2+ concentration increased 1.5-fold, and the mitochon- drial membrane potential decreased by 20% in the combined treatment. Simultaneously, the atomic force microscopy (AFM) re- sults suggest that cells treated with a combination of cinobufacini and curcumin varied significantly in shape and ultrastructure. Collapsed cells with leaking cytoplasm, blebbing pores and emerging apoptotic bodies were prevalent. The nanoparticle size increased from 70 nm when the cells were treated with 25 μg/mL cinobufacini to 190 nm when the cells were treated with 25 μg/mL cinobufacini and 8 μg/mL curcumin. The size increase resulted in the cell membrane becoming considerably rough. These results can improve our understanding of combination treatments. Specifically, the combination of cinobufacini and curcumin may potentially find use as a novel cervical carcinoma treatment. Additionally, AFM is a powerful tool that can be used to explore cellular morphologies and ultrastructures.  相似文献   

17.
In this study, the anti-invasion effects of(-)-epigallocatechin-3-gallate(EGCG) mixed with ascorbic acid(Vc) on human lung carcinoma 95-D cells in vitro were examined and the synergism of the combination of EGCG and Vc was evaluated. Soft agar colony formation assay, cell migration assay, invasion assay, western blot analysis of NF-κB, in situ detection of cellular oxidative stress, and statistical analysis were assessed. The results showed that combining EGCG with Vc could inhibit clone forming rate of 95-D cell by 73.2%, reduce the migration ability of 95-D cell by 65.9%, and decrease the intracellular reactive oxygen species(ROS) level by 76.8%. The results of western blot proved that Vc enhanced the activity of EGCG in inhibiting NF-κB localization. It is speculated that the combination of EGCG and Vc can strongly suppress the proliferation and metastasis of lung carcinoma cells in a synergic manner, possibly with a mechanism associated with the scavenging of reactive oxygen species.  相似文献   

18.
Long chain polyunsaturated fatty adds, i. e., docosahexaenoic acid (DHA or C22 : 6n - 3), amchidonic acid (AA or C20 : 4n -6) have been identified as essential fatty acids and play an important role in growth and development of infants. Measurement of fatty acid composition is usually by collection of blood, but to obtain blood in infants is difficult. Nowadays, the fatty acid composition can be estimated by collecting buccal mucosal cells, which can avoid repeated blood sampling. The of this paper is to compare the fatty acid composition of cheek cells with that of plasma and red blood cells (RBCs). In this study, twenty-seven infants were enrolled, and buccal mucosal cells and blood samples were obtained from these infants of the same time. Fatty acid composition of buccal mucosal cells, plasma and RBCs were measured by capillary gas chromatography. The results show that the contents of AA and DHA in the buccal macosal cells are correlated well with that in the plasma [r=0.36 (P=0.042) and r =0.38 (P =0.033), respectively]. The ratio of AA to DHA is 1.32% in buccal mucosal cells, 1.60% in plasma and 1.55% in RBCs and there are no significant differences among groups (P = 0.134). It shows that the fatty acid composition in buccal macosal cells can reflect the fat nutrition status in infants and can be detected by capillary gas chromatography. Estimating fatty acid composition of buceal mucosal cells in infants by capillary gas chromatography is feasible, and because of its noninvasiveness, it can be suitable for nutrition research in infants.  相似文献   

19.
The pH value plays an important role in the bioleaching of sulphide minerals. The effect of pH values on the extracellular poly-saccharide secreted by Acidithiobacillus ferrooxidans was investigated in different phases of bacterial growth during chalcopyrite bioleach-ing. It is found that extracellular polysaccharide secretion from the cells attached to chalcopyrite is more efficiently than that of the free cells in the bioleaching solution. Three factors, pH values, the concentration of soluble metal ions, and the bacterial growth and metabolism, affect extracellular polysaccharide secretion in the free cells, and are related to the bacterial growth phase. Extracellular polysaccharide secretion from the attached cells is mainly dependent on the pH value of the bacterial culture.  相似文献   

20.
Self-assembly of micro parts on normal glass substrate   总被引:3,自引:0,他引:3  
Fluidic self-assembly is an approach by which micro parts less than one millimeter in size can be driven by the capillary force of a certain adhesive liquid and be fixed onto the desired sites on some substrates. Normal glass with the composition of Na2SiO3CaSiO34SiO2 has been widely used in fluidic microelectromechanical systems (MEMS) and bio-MEMS devices. We investigate the MEMS self-assembly experiment on normal glass substrate. The results of scanning electron microscopy (SEM) show that micro-parts of 400 μm400 μm squares can be precisely assembled in the expected area of the normal glass substrate.  相似文献   

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