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Vitro Cell Culture (vitro + cell_culture)
Terms modified by Vitro Cell Culture Selected AbstractsInflammatory cytokines augments TGF-,1-induced epithelial-mesenchymal transition in A549 cells by up-regulating T,R-ICYTOSKELETON, Issue 12 2008Xiangde Liu Abstract Epithelial-mesenchymal transition (EMT) is believed to play an important role in fibrosis and tumor invasion. EMT can be induced in vitro cell culture by various stimuli including growth factors and matrix metalloproteinases. In this study, we report that cytomix (a mixture of IL-1,, TNF-, and IFN-,) significantly enhances TGF-,1-induced EMT in A549 cells as evidenced by acquisition of fibroblast-like cell shape, loss of E-cadherin, and reorganization of F-actin. IL-1, or TNF-, alone can also augment TGF-,1-induced EMT. However, a combination of IL-1, and TNF-, or the cytomix is more potent to induce EMT. Cytomix, but not individual cytokine of IL-1,, TNF-, or IFN-,, significantly up-regulates expression of TGF-, receptor type I (T,R-I). Suppression of T,R-I, Smad2 or Smad3 by siRNA partially blocks EMT induction by cytomix plus TGF-,1, indicating cytomix augments TGF-,1-induced EMT through enhancing T,R-I and Smad signaling. These results indicate that inflammatory cytokines together with TGF-,1 may play an important role in the development of fibrosis and tumor progress via the mechanism of epithelial-mesenchymal transition. Cell Motil. Cytoskeleton 2008. © 2008 Wiley-Liss, Inc. [source] Limonoids as cancer chemopreventive agentsJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 3 2006Sohail Ejaz Abstract Nutritional research on the health benefits of substances in plant foods has recently advanced to a new stage. The research frontier has moved from study of classical vitamin deficiency diseases to study of the thousands of phytochemicals that may have important physiological effects. Recent research suggests that citrus fruit consumers may be getting another health benefit from orange juice and other citrus products called limonoids, which appear to possess substantial anticancer activity. Limonoids are highly oxidized triterpenes present in Rutaceae and Maliaceae families. Several citrus limonoids have recently been subjected to anticancer screening utilizing laboratory animals and human breast cancer cells. The experimental results described that citrus limonoids may provide substantial anticancer actions. The compounds have been shown to be free of toxic effects in animal models, so potential exists for the use of limonoids against human cancer in either natural fruits, in citrus fortified with limonoids, or in purified forms of specific limonoids. Although the initial studies are very promising they have been conducted primarily with in vitro cell culture and animal models. Thus, research is needed to determine whether the limonoids may be useful in preventing or treating cancer in humans. Copyright © 2005 Society of Chemical Industry [source] Electro-synthesized PEDOT/glutamate chemically modified electrode: a combination of electrical and biocompatible featuresPOLYMER INTERNATIONAL, Issue 5 2008Jianfei Che Abstract BACKGROUND: Neural prosthetic devices have been developed that can facilitate the stimulation and recording of electrical activity when implanted in the central nervous system. The key parts of the devices are metal (gold) electrodes; however, surface modification of the gold electrode is desired. Conducting polymers are promising candidates for this purpose. RESULTS: A conducting polymer, poly(3,4-ethylenedioxythiophene) (PEDOT), was electro-polymerized onto gold electrodes with a neural transmitter of glutamate (Glu) as dopant. A protocol of ion exchange was employed due to the difficulty of direct incorporation of Glu into PEDOT. Sodium p -toluenesulfonate (TSNa) was chosen as the first dopant and subsequent incorporation of Glu was accomplished via ion exchange. The electrochemical properties of the resultant PEDOT/Glu were studied using electrochemical impedance spectroscopy and cyclic voltammetry. The purpose of incorporating Glu was to improve the biocompatibility of the coated electrode. The PEDOT/Glu-coated electrode showed better cell attachment compared with a PEDOT/TSNa-coated electrode in in vitro cell culture of PC12. The stability of PEDOT was studied by immersing the coated electrode in a biologically relevant reducing agent of glutathione. CONCLUSION: The charge capacity of the coated electrode had an initial slight decrease and then remained unchanged. Good electro-activity was conserved, indicating the superior stability of PEDOT in the biological environment. Copyright © 2007 Society of Chemical Industry [source] Role of CD21 antigen in diffuse large B-cell lymphoma and its clinical significanceBRITISH JOURNAL OF HAEMATOLOGY, Issue 4 2004Masaki Otsuka Summary Recent advances in immunological and molecular technology have prompted proposals to change tumour classification and treatment strategies. Cell surface antigens are now easy to access, and tumour origins and clinical characteristics are now readily identifiable. However, in diffuse large B-cell lymphoma (DLBCL), one of the heterogeneous forms of haematological malignancy, the clinical significance of tumour surface antigens has not been well documented. We analysed the tumour surface antigens of 50 tumours from newly diagnosed DLBCL patients by flow cytometry in accordance with their clinical characteristics and followed the patients for a median 3·7 years. Statistical analysis showed that CD21 expression was significantly negatively associated with mortality in DLBCL (CD21 negative versus positive; relative risk = 2·36, P < 0·05). As a result of these clinical observations, we generated CD21-overexpressed (CD21+) lymphoma cell lines after gene transfection and analysed tumour cell growth in vivo in immunocompromised mice. Mice challenged with vector-only transfectants and parental cells as controls died within 50 d. In contrast, mice injected with CD21+ transfectants exhibited significantly reduced tumour growth and 83% survived long term (versus control groups; P < 0·05). Interestingly, all established CD21+ transfectants (six clones from different bulks) showed homotypic aggregation during in vitro cell culture, and anti-CD21 antibodies did not block this aggregation. Expression of CD21 is strongly associated with increased survival in DLBCL in vivo. CD21 expression may be indirectly concerned with the expression of additional cell adhesion molecules. [source] Establishment of six new human biliary tract carcinoma cell lines and identification of MAGEH1 as a candidate biomarker for predicting the efficacy of gemcitabine treatmentCANCER SCIENCE, Issue 4 2010Hidenori Ojima The aim of this study was to establish new biliary tract carcinoma (BTC) cell lines and identify predictive biomarkers for the potential effectiveness of gemcitabine therapy. Surgical specimens of BTC were transplanted directly into immunodeficient mice to establish xenografts, then subjected to in vitro cell culture. The gemcitabine sensitivity of each cell line was determined and compared with the genome-wide gene expression profile. A new predictive biomarker candidate was validated using an additional cohort of gemcitabine-treated BTC cases. From 55 BTC cases, we established 19 xenografts and six new cell lines. Based on their gemcitabine sensitivity, 10 BTC cell lines (including six new and four publicly available ones) were clearly categorized into two groups, and MAGEH1 mRNA expression in the tumor cells showed a significant negative correlation with their sensitivity to gemcitabine. Immunohistochemically, MAGEH1 protein was detected in three (50%) out of six sensitive cell lines, and four (100%) out of four resistant cell lines. In the validation cohort of gemcitabine-treated recurrence cases, patients were categorized into "effective" and "non-effective" groups according to the RECIST guidelines for assessment of chemotherapeutic effects. MAGEH1 protein expression was detected in two (40%) out of five "effective" cases and all four (100%) "non-effective" cases. We have established a new BTC bioresource that covers a wide range of biological features, including drug sensitivity, and is linked with clinical information. Negative expression of MAGEH1 protein serves as a potential predictive marker for the effectiveness of gemcitabine therapy in BTC. (Cancer Sci 2010; 101: 882,888) [source] 4245: Non-surgical strategies for PCO preventionACTA OPHTHALMOLOGICA, Issue 2010IM WORMSTONE Purpose Surgical approaches and IOL design have gone some way to reduce the rate of PCO progression. Despite these efforts PCO remains a common and important problem which diminishes the visual quality of patients and is a major financial burden on healthcare providers. If we are to effectively respond to the problem of PCO then a biological solution has to be adopted to reduce/prevent formation of light scattering changes. Methods Methods have been employed to investigate PCO development, which include in vitro cell culture and capsular bag models; in vivo animal models and post-mortem analysis. These have greatly aided our understanding of PCO. Results A number of basic approaches have been identified to prevent PCO. 1) To kill the entire lens epithelial population. This will require a pharmacological agent, therefore delivery of this drug needs to be localised to the target cells, but have limited access to non-target cells; closed capsular bag systems such as perfect capsule provides opportunity to achieve this aim. 2) Maintenance of a cell monolayer on the posterior capsule. In particular the role of TGF, has been investigated, which is known to cause matrix deformation. Disruption of TGF, signalling pathways can suppress matrix deformation and thus reduce light scatter. 3) Recreation of a lens is the ultimate solution. While it has been shown that lens fibre differentiation can be promoted in animal systems, perfect formation of the lens is not achieved and the protein density is typically low relative to the native lens. Conclusion Strategies to prevent PCO are being actively developed, which will are greatly aided by improved drug delivery systems. The development of biological/pharmacological approaches in concert with improved surgical methods and IOL designs should yield benefit to patients. Commercial interest [source] INDIVIDUAL AND COMBINED CYTOTOXIC EFFECTS OF THE MAJOR FOUR AFLATOXINS IN DIFFERENT IN VITRO STABILIZED SYSTEMSJOURNAL OF FOOD BIOCHEMISTRY, Issue 5 2010CORNELIA BRAICU ABSTRACT The present study aims to investigate the cytotoxic effect of the major aflatoxins (B1, B2, G2 and G2) and also aflatoxin combination, using a simple, rapid and cheap cytotoxicity test like MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) assay in three in vitro models (human umbilical vein endothelial cells [HUVEC], human lung fibroblasts [HFL] and A2780 cell line) and to extrapolate the data to in vivo situation using a prediction model. A difference in cell sensitivity has been observed for B1 and B1 + B2, in the following order A2789 > HFL > HUVEC, while for B2, G1, G2, Mix (B1 + B2 + G1 + G2) the order was HFL > A2789 > HUVEC when comparing the IC50 (half maximal inhibitory concentration) values. We confirm that in vitro cytotoxicity test MTT assay is able to predict in vivo toxicity, at least for aflatoxins using the prediction model. The values of LD50 (lethal dose 50%) calculated from experiments are different for each cell line. This fact may indicate that some species are more resistant than other and target organs are not necessarily those predicted, because the A2780 ovarian cancer cells seem to be more sensitive to B1 than cells of endothelial or fibroblasts origin. PRACTICAL APPLICATIONS This study is in concordance with the international tendency that refined the current techniques to lessen pain or distress, to reduce the number of animals necessary for a particular test or to replace animals with non-whole-animal models, such as in vitro cell cultures. The practical application of such methodologies may help solve the economic problem related to very expensive in vivo toxicology studies and implement preventive methods based on the calculated data and known mechanism of action of individual or combined toxins easily studied in vitro. The nature of coexistence of many types of mycotoxins in complex environmental samples, such as food and water, has been reported worldwide. How these mycotoxins might affect human health in combination is largely unknown. This study had, as a goal, to test the toxicity of the four aflatoxins and aflatoxin combination on human cells. Due to the lack of aflatoxins mixture data regarding the human cytotoxicity, the aim of this study was to specify, evaluate and predict the combined effects of mycotoxin mixtures. [source] Progress and limitations in the use of in vitro cell cultures to serve as a permeability screen for the blood-brain barrierJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 11 2001Mark Gumbleton Abstract A relatively simple, widely applicable, and robust in vitro method of predicting blood-brain barrier (BBB) permeability to central nervous system-acting drugs is an increasing need. A cell-based model offers the potential to account for transcellular and paracellular drug diffusional processes, metabolism, and active transport processes, as well as nondefined interactions between a drug and cellular material that may impact upon a membrane's overall permeability profile. Any in vitro BBB cell model to be utilized for the transendothelial BBB permeability screening of potential central nervous system drugs must display reproducible solute permeability, and a number of other general criteria including: a restrictive paracellular barrier; a physiologically realistic cell architecture; the functional expression of key transporter mechanisms; and allow ease of culture to meet the technical and time constraints of a screening program. This article reviews the range of in vitro cell-based BBB models available, including the primary/low passage bovine and porcine brain endothelial cultures as well as the spectrum of immortalized brain endothelial cell lines that have been established. The article further discusses the benefits and limitations of exploiting such systems as in vitro BBB permeability screens. © 2001 Wiley-Liss, Inc. and the American Pharmaceutical Association J Pharm Sci 90:1681,1698, 2001 [source] | |||||||||||||