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Sample records for cellular proliferation indices

  1. Effect of propolis on mitotic and cellular proliferation indices in human blood lymphocytes

    Energy Technology Data Exchange (ETDEWEB)

    Montoro, A.; Almonacid, M.; Villaescusa, J. [Valencia Hospital Univ. la Fe, Servicio de Proteccion Radiologica (Spain); Barquinero, J. [Barcelona Univ. Autonom, Servicio de Dosimetria Biologica, Unidad de Antropologia, Dept. de Biologia Animal, Vegetal y Ecologia, barcelona (Spain); Barrios, L. [Barcelona Univ. Autonoma, Dept. de Biologia Celular y Fisiologia. Unidad de Biologia Celular (Spain); Verdu, G. [Valencia Univ. Politecnica, Dept. de Ingenieria Quimica y Nuclear (Spain); Perez, J. [Hospital la Fe, Seccion de Radiofisica, Servicio de Radioterapia, valencia (Spain)

    2006-07-01

    The study of the frequency of chromosomal aberrations per cell is the tool used in Biological dosimetry studies. Using dose-effect calibration curve obtained in our laboratory, we can evaluate the radioprotector effect of the EEP (ethanolic extract of propolis) in cultures in vitro. Propolis is the generic name for resinous substance collected by honeybees. The results showed a reduction in chromosomal aberrations's frequency of up to 50 %. The following study consisted of analyzing human peripheral blood lymphocytes exposed to 2 Gy {gamma} rays, in presence and absence of EEP, the change in the frequency of chromosome aberrations was analysed with biological dosimetry. The protection against the formation of dicentric and ring was dose-dependent, but there seemed to be a maximum protection, i.e. a further increase in the concentration of EEP does not show additional protection. This work studies the effect of the EEP of the cellular cycle using the mitotic and cellular proliferation index, as an alternative for the screening cytostatic activity. The results indicate that the lymphocytes which were cultures in presence of EEP exhibited a significant and dependent-concentration decrease in mitotic index and proliferation kinetics. The possible mechanisms involved in the radioprotective influence of EEP are discussed. (authors)

  2. Effect of propolis on mitotic and cellular proliferation indices in human blood lymphocytes

    International Nuclear Information System (INIS)

    The study of the frequency of chromosomal aberrations per cell is the tool used in Biological dosimetry studies. Using dose-effect calibration curve obtained in our laboratory, we can evaluate the radioprotector effect of the EEP (ethanolic extract of propolis) in cultures in vitro. Propolis is the generic name for resinous substance collected by honeybees. The results showed a reduction in chromosomal aberrations's frequency of up to 50 %. The following study consisted of analyzing human peripheral blood lymphocytes exposed to 2 Gy γ rays, in presence and absence of EEP, the change in the frequency of chromosome aberrations was analysed with biological dosimetry. The protection against the formation of dicentric and ring was dose-dependent, but there seemed to be a maximum protection, i.e. a further increase in the concentration of EEP does not show additional protection. This work studies the effect of the EEP of the cellular cycle using the mitotic and cellular proliferation index, as an alternative for the screening cytostatic activity. The results indicate that the lymphocytes which were cultures in presence of EEP exhibited a significant and dependent-concentration decrease in mitotic index and proliferation kinetics. The possible mechanisms involved in the radioprotective influence of EEP are discussed. (authors)

  3. Computer Studies on the Mechanisms Controlling Cellular Proliferation

    International Nuclear Information System (INIS)

    A model of the autoregulation of mitotic and functional activity of the cells is used (R. Tsanev and B. Sendov, J. theoret. Biol. 12 (1966) 327) to study by means of a digital computer the reaction of different cellular systems (a synchronous cellular population, liver and epidermis) to injuring agents disturbing the steady state of the system. The reaction of the cellular models to different kinds of injury was found to imitate adequately some particular features of the real regenerative processes. The model may also be useful to check different hypotheses concerning the mechanisms by which irradiation affects cellular proliferation. (author)

  4. Cellular proliferation after experimental glaucoma filtration surgery

    International Nuclear Information System (INIS)

    We used light microscopic autoradiography to determine the time course of cellular incorporation of tritiated thymidine (a correlate of cell division) following glaucoma filtration surgery in seven eyes of four cynomolgus monkeys with experimental glaucoma. Incorporation of tritiated thymidine was detected as early as 24 hours postoperatively. Peak incorporation occurred five days postoperatively and had returned to baseline levels by day 11. Cells incorporating tritiated thymidine included keratocytes, episcleral cells, corneal and capillary endothelial cells, and conjunctival and corneal epithelial cells. Transmission electron microscopy was correlated with the autoradiographic results to demonstrate that fibroblasts were dividing on the corneoscleral margin. These findings have potential clinical implications for the use of antiproliferative agents after filtration surgery

  5. Cellular proliferation in the rat pineal gland during postnatal development

    OpenAIRE

    Carvajal, J.C.; Carbajo, S.; Gómez Esteban, M.B.; Alvarez-Morujo Suárez, A.J.; Muñoz Barragan, L.

    1998-01-01

    To establish a possible correlation between the rate of cellular proliferation and already documented functional and morphological characteristics of the rat pineal gland during postnatal development, the bromodeoxyuridine labelling method was used to evaluate the fraction of cells at the S phase of the cell cycle in paraffin sections from I-, 7-, 14- and 28-day-old rats. Numerical density, taken as an indirect measure of cell hypertrophy, was also evaluated. D...

  6. Effects of β-TCP Ceramics on Ostcoblast Cellular Proliferating, Mineralization and Osteocalcin Expression

    Institute of Scientific and Technical Information of China (English)

    QI Zhitao; ZHANG Qihuan; ZHENG Qiang; DAI Honglian; WANG Zisheng; QIU Ming; LI Shipu

    2012-01-01

    After co-cultrured osteoblast with β-TCP ceramics,the cellular proliferating,mineralization and osteocalcin expression were studied.MTT assay showed that β-TCP ceramics had no affect on cellular proliferating.Laser scanning confocal detection showed that β-TCP ceramics could increase the mineralization level of osteoblast.Furthermore,RT-PCR showed that β-TCP could increase the expression level of osteocalcin.Those results indicate β-TCP ceramics had perfect biocompatibility and increased the mineralization of osteoblast to accelerate osteogenesis by means of affecting the expression of genes involving in osteogeneticprocess.

  7. Stimulation of Cellular Proliferation by Hepatitis B Virus X Protein

    Directory of Open Access Journals (Sweden)

    Charles R. Madden

    2001-01-01

    Full Text Available Chronic infection with the hepatitis B virus (HBV is a known risk factor in the development of human hepatocellular carcinoma (HCC. The HBV-encoded X protein, HBx, has been investigated for properties that may explain its cancer cofactor role in transgenic mouse lines. We discuss here recent data showing that HBx is able to induce hepatocellular proliferation in vitro and in vivo. This property of HBx is predicted to sensitize hepatocytes to other HCC cofactors, including exposure to carcinogens and to other hepatitis viruses. Cellular proliferation is intimately linked to the mechanism(s by which most tumor-associated viruses transform virus-infected cells. The HBx alteration of the cell cycle provides an additional mechanism by which chronic HBV infection may contribute to HCC.

  8. Cellular indicators of preclinical phases of leukemia

    International Nuclear Information System (INIS)

    The objectives of this project are to: (1) define the stages of pathological progression of myelogenous leukemia occurring in dogs undergoing continuous radiation exposure; (2) develop sensitive predictors of the pathological responses based on early cellular events; and (3) utilize cell cloning methods to clarify mechanisms of early hemopoietic dysfunctions. Based on previous work which showed that myelogenous leukemia occurs with a 50% incidence in beagles exposed for protracted periods to 60Co gamma radiation, beagles are irradiated continuously (i.e., 22 hours/day at the dose rate of 10 R/day) at the dose rate of 10 R/day. The experimental approach is then to assess serially the phase related changes within the granulopoietic system of the exposed animals. Assessment employs both in vitro and in vivo assays aimed at compartmentalizing the granulopoietic system. The marrow compartments presently being examined include: (1) the granulocyte-monocyte committed stem cells (GM-CFned by two-dimensional electrophoresis to detect disease and pollutant related changes. Assessment of human risk associated with nuclearing collective dose commitment will result in more attention being paid to potential releases of radionuclides at relatively short times after disposal

  9. The Inhibitory Effect of Endostatin and Doxycycline Administration on B16 Melanoma Angiogenesis and Cellular Proliferation

    Institute of Scientific and Technical Information of China (English)

    Lisha Qi; Shiwu Zhang; Danfang Zhang; Xiaojin Yin; Sen Wang; Baochun Sun

    2008-01-01

    OBJECTIVE To investigate the effect of endostatin and doxycycline on melanoma cellular proliferation and tumor angiogenesis.METHODS The effects of endostatin and doxvcycline were studied in mice transplanted with B16 melanoma cells.The mice were divided into 4 groups that were trea ted as follows:endostatin treatment(E group),doxycycline treatment(D group),endostatin plus doxycycline trearment(DE group),controls(C group)received no treatment.Following 9 days of treatment the tumor tissue was removed to compare the differences in the tumor necrotic rate and micro-vessel density (MVD)among the different groups.Immunohistochemical staining was conducted to detect the expression of proliferating cell nuclear antigen(PCNA)in the different groups.RESULTS The MVD of the 3 experimental groups was significantly less than the control group,(F=10.888,P<0.05),indicating that doxycycline and endostatin can inhibit tumor angiogenesis by decreasing the tumor blood supply.This effect results in inhibition of tumor cellular proliferation and promotion of tumor cell necrosis.The tumor cell necrotic ra te of the 3 experimental groups were all significantly higher than the C group(F=7.229,P<0.05)and the difference between the DE and C groups also was statistically significant.PCNA expression in all 3 experimental groups was statistically less than the C group(F=17.729,P<0.05).CONCLUSION The combined use of endostatin and doxycyCline in vivo can influence PCNA exDression and angiogenesis in melanoma,and significantly inhibit melanoma cellular proliferation.

  10. Cellular, Molecular Consequences of Peroxisome Proliferator- Activated Receptor-δ Activation in Ovarian Cancer Cells

    Directory of Open Access Journals (Sweden)

    Sara Vignati

    2006-10-01

    Full Text Available Peroxisome proliferator-activated receptor-δ (PPAR-δ is a ligand-activated transcription factor. In addition to its canonical role in lipid, glucose metabolism, PPAR-δ controls cell proliferation, death, differentiation in several tissues. Here we have examined the expression of PPAR-δ in ovarian tumors, the cellular, molecular consequences of its activation in ovarian cancer cells. PPAR-δ was expressed in a large number of epithelial ovarian tumors, cell lines. The PPAR-δ lig, ciglitazone inhibited the growth, clonogenic survival of ovarian cancer cells, inducing cell cycle arrest, cell death. Growth inhibition by ciglitazone was reversed by the PPAR-δ antagonist GW9662, indicating the involvement of PPAR-δ- dependent mechanisms. Microarray-based gene profiling revealed complex changes in the transcriptional program of ovarian cancer cells on treatment with ciglitazone, identified multiple pathways that may contribute to PPAR-δ ligands' antitumor activity. Genes upregulated by ciglitazone were predominantly associated with metabolic, differentiation, tumorsuppressor pathways, whereas downregulated genes were involved in cell proliferation, cell cycle, cell organization, steroid biosynthesis. Collectively, our data indicate that PPAR-δ activation by selective agonists is a valid strategy for ovarian cancer therapy, prevention, should be tested alone, in combination with other anticancer drugs.

  11. ETO2 coordinates cellular proliferation and differentiation during erythropoiesis

    OpenAIRE

    Goardon, Nicolas; Lambert, Julie A; Rodriguez, Patrick; Nissaire, Philippe; Herblot, Sabine; Thibault, Pierre; Dumenil, Dominique; Strouboulis, John; Romeo, Paul-Henri; Hoang, Trang

    2006-01-01

    The passage from proliferation to terminal differentiation is critical for normal development and is often perturbed in malignancies. To define the molecular mechanisms that govern this process during erythropoiesis, we have used tagging/proteomics approaches and characterized protein complexes nucleated by TAL-1/SCL, a basic helix–loop–helix transcription factor that specifies the erythrocytic lineage. In addition to known TAL-1 partners, GATA-1, E2A, HEB, LMO2 and Ldb1, we identify the ETO2...

  12. Structure and biochemical characterization of proliferating cellular nuclear antigen from a parasitic protozoon

    Energy Technology Data Exchange (ETDEWEB)

    Cardona-Felix, Cesar S.; Lara-Gonzalez, Samuel; Brieba, Luis G. (LNLS)

    2012-02-08

    Proliferating cellular nuclear antigen (PCNA) is a toroidal-shaped protein that is involved in cell-cycle control, DNA replication and DNA repair. Parasitic protozoa are early-diverged eukaryotes that are responsible for neglected diseases. In this work, a PCNA from a parasitic protozoon was identified, cloned and biochemically characterized and its crystal structure was determined. Structural and biochemical studies demonstrate that PCNA from Entamoeba histolytica assembles as a homotrimer that is able to interact with and stimulate the activity of a PCNA-interacting peptide-motif protein from E. histolytica, EhDNAligI. The data indicate a conservation of the biochemical mechanisms of PCNA-mediated interactions between metazoa, yeast and parasitic protozoa.

  13. Human Homolog of Drosophila Ariadne (HHARI) is a marker of cellular proliferation associated with nuclear bodies

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    Elmehdawi, Fatima; Wheway, Gabrielle; Szymanska, Katarzyna [Division of Clinical Sciences, Leeds Institute of Molecular Medicine, Level 8, Wellcome Trust Brenner Building, University of Leeds, Leeds, LS9 7TF West Yorkshire (United Kingdom); Adams, Matthew [BioScreening Technology Group, Biomedical Health Research Center, Wellcome Trust Brenner Building, University of Leeds, Leeds, LS9 7TF West Yorkshire (United Kingdom); High, Alec S. [Department of Histopathology, Bexley Wing, St. James' s University Hospital, Beckett Street, Leeds, LS9 7TF West Yorkshire (United Kingdom); Johnson, Colin A., E-mail: c.johnson@leeds.ac.uk [Division of Clinical Sciences, Leeds Institute of Molecular Medicine, Level 8, Wellcome Trust Brenner Building, University of Leeds, Leeds, LS9 7TF West Yorkshire (United Kingdom); Robinson, Philip A. [Division of Clinical Sciences, Leeds Institute of Molecular Medicine, Level 8, Wellcome Trust Brenner Building, University of Leeds, Leeds, LS9 7TF West Yorkshire (United Kingdom)

    2013-02-01

    HHARI (also known as ARIH1) is an ubiquitin-protein ligase and is the cognate of the E2, UbcH7 (UBE2L3). To establish a functional role for HHARI in cellular proliferation processes, we performed a reverse genetics screen that identified n=86/522 (16.5%) ubiquitin conjugation components that have a statistically significant effect on cell proliferation, which included HHARI as a strong hit. We then produced and validated a panel of specific antibodies that establish HHARI as both a nuclear and cytoplasmic protein that is expressed in all cell types studied. HHARI was expressed at higher levels in nuclei, and co-localized with nuclear bodies including Cajal bodies (p80 coilin, NOPP140), PML and SC35 bodies. We confirmed reduced cellular proliferation after ARIH1 knockdown with individual siRNA duplexes, in addition to significantly increased levels of apoptosis, an increased proportion of cells in G2 phase of the cell cycle, and significant reductions in total cellular RNA levels. In head and neck squamous cell carcinoma biopsies, there are higher levels of HHARI expression associated with increased levels of proliferation, compared to healthy control tissues. We demonstrate that HHARI is associated with cellular proliferation, which may be mediated through its interaction with UbcH7 and modification of proteins in nuclear bodies. -- Highlights: ► We produce and validate new antibody reagents for the ubiquitin-protein ligase HHARI. ► HHARI colocalizes with nuclear bodies including Cajal, PML and SC35 bodies. ► We establish new functions in cell proliferation regulation for HHARI. ► Increased HHARI expression associates with squamous cell carcinoma and proliferation.

  14. Increased cellular proliferation in rat skeletal muscle and tendon in response to exercise

    DEFF Research Database (Denmark)

    Skovgaard, Dorthe; Bayer, Monika L; Mackey, Abigail;

    2010-01-01

    -derived standardized uptake values were calculated for Achilles tendons and calf muscles and compared to gene expression and immunohistochemical evaluations of Ki67. RESULTS: Treadmill running induced increased uptake of FLT uptake in calf muscles (30%; p < 0.001) and in Achilles tendon (21%, p < 0.001). The image......-derived results were supported by a correlation in calf muscle to Ki67 (protein and mRNA level), while this coherence was not found in tendon. CONCLUSION: FLT-PET seems to be a promising tool for imaging of exercise-induced cellular proliferation in musculo-tendinous tissue.......PURPOSE: The purpose of this study is to investigate exercise-induced cellular proliferation in rat skeletal muscle/tendon with the use of 3'-[F-18]fluoro-3'deoxythymidine (FLT) and to quantitatively study concomitant changes in the proliferation-associated factor, Ki67. PROCEDURES: Wistar rats (n...

  15. Tetraspanin CD9 modulates human lymphoma cellular proliferation via histone deacetylase activity

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    Herr, Michael J. [Vascular Biology Center of Excellence, The University of Tennessee Health Science Center, Memphis, TN 38163 (United States); Department of Medicine, The University of Tennessee Health Science Center, Memphis, TN 38163 (United States); Department of Molecular Sciences, The University of Tennessee Health Science Center, Memphis, TN 38163 (United States); Department of Surgery, The University of Tennessee Health Science Center, Memphis, TN 38163 (United States); Longhurst, Celia M.; Baker, Benjamin [Vascular Biology Center of Excellence, The University of Tennessee Health Science Center, Memphis, TN 38163 (United States); Homayouni, Ramin [Department of Biology, Bioinformatics Program, University of Memphis, Memphis, TN 38152 (United States); Speich, Henry E.; Kotha, Jayaprakash [Vascular Biology Center of Excellence, The University of Tennessee Health Science Center, Memphis, TN 38163 (United States); Jennings, Lisa K., E-mail: ljennings@uthsc.edu [Vascular Biology Center of Excellence, The University of Tennessee Health Science Center, Memphis, TN 38163 (United States); Department of Medicine, The University of Tennessee Health Science Center, Memphis, TN 38163 (United States); Department of Molecular Sciences, The University of Tennessee Health Science Center, Memphis, TN 38163 (United States); Department of Surgery, The University of Tennessee Health Science Center, Memphis, TN 38163 (United States); Department of Biology, Bioinformatics Program, University of Memphis, Memphis, TN 38152 (United States)

    2014-05-16

    Highlights: • CD9 is differentially expressed in human Burkitt’s lymphoma cells. • We found that CD9 expression promotes these cells proliferation. • CD9 expression also increases HDAC activity. • HDAC inhibition decreased both cell proliferation and importantly CD9 expression. • CD9 may dictate HDAC efficacy and play a role in HDAC regulation. - Abstract: Non-Hodgkin Lymphoma (NHL) is a type of hematological malignancy that affects two percent of the overall population in the United States. Tetraspanin CD9 is a cell surface protein that has been thoroughly demonstrated to be a molecular facilitator of cellular phenotype. CD9 expression varies in two human lymphoma cell lines, Raji and BJAB. In this report, we investigated the functional relationship between CD9 and cell proliferation regulated by histone deacetylase (HDAC) activity in these two cell lines. Introduction of CD9 expression in Raji cells resulted in significantly increased cell proliferation and HDAC activity compared to Mock transfected Raji cells. The increase in CD9–Raji cell proliferation was significantly inhibited by HDAC inhibitor (HDACi) treatment. Pretreatment of BJAB cells with HDAC inhibitors resulted in a significant decrease in endogenous CD9 mRNA and cell surface expression. BJAB cells also displayed decreased cell proliferation after HDACi treatment. These results suggest a significant relationship between CD9 expression and cell proliferation in human lymphoma cells that may be modulated by HDAC activity.

  16. Pulsed Electromagnetic Field Stimulates Cellular Proliferation in Human Intervertebral Disc Cells

    OpenAIRE

    Lee, Hwan-Mo; Kwon, Un-Hye; Kim, Hyang; Kim, Ho-Joong; Kim, Boram; Park, Jin-Oh; Moon, Eun-Soo; Moon, Seong-Hwan

    2010-01-01

    Purpose The purpose of this study is to investigate the mechanism of cellular proliferation of electromagnetic field (EMF) on human intervertebral disc (IVD) cells. Materials and Methods Human IVD cells were cultured three-dimensionally in alginate beads. EMF was exposed to IVD cells with 650Ω, 1.8 millitesla magnetic flux density, 60 Hz sinusoidal wave. Cultures were divided into a control and EMF group. Cytotoxicity, DNA synthesis and proteoglycan synthesis were measured by MTT assay, [3H]-...

  17. Human papillomavirus type 16 E7 perturbs DREAM to promote cellular proliferation and mitotic gene expression

    OpenAIRE

    DeCaprio, James A.

    2013-01-01

    Study of the small DNA tumor viruses continues to provide valuable new insights into oncogenesis and fundamental biological processes. While much has already been revealed about how the human papillomaviruses (HPVs) can transform cells and contribute to cervical and oropharyngeal cancer, there clearly is much more to learn. In this issue of Oncogene, Pang et al. demonstrate that the high-risk HPV16 E7 oncogene can promote cellular proliferation by interacting with the DREAM (DP, RB-like, E2F ...

  18. HPV16 E2 could act as down-regulator in cellular genes implicated in apoptosis, proliferation and cell differentiation

    Directory of Open Access Journals (Sweden)

    Valencia-Hernández Armando

    2011-05-01

    Full Text Available Abstract Background Human Papillomavirus (HPV E2 plays several important roles in the viral cycle, including the transcriptional regulation of the oncogenes E6 and E7, the regulation of the viral genome replication by its association with E1 helicase and participates in the viral genome segregation during mitosis by its association with the cellular protein Brd4. It has been shown that E2 protein can regulate negative or positively the activity of several cellular promoters, although the precise mechanism of this regulation is uncertain. In this work we constructed a recombinant adenoviral vector to overexpress HPV16 E2 and evaluated the global pattern of biological processes regulated by E2 using microarrays expression analysis. Results The gene expression profile was strongly modified in cells expressing HPV16 E2, finding 1048 down-regulated genes, and 581 up-regulated. The main cellular pathway modified was WNT since we found 28 genes down-regulated and 15 up-regulated. Interestingly, this pathway is a convergence point for regulating the expression of genes involved in several cellular processes, including apoptosis, proliferation and cell differentiation; MYCN, JAG1 and MAPK13 genes were selected to validate by RT-qPCR the microarray data as these genes in an altered level of expression, modify very important cellular processes. Additionally, we found that a large number of genes from pathways such as PDGF, angiogenesis and cytokines and chemokines mediated inflammation, were also modified in their expression. Conclusions Our results demonstrate that HPV16 E2 has regulatory effects on cellular gene expression in HPV negative cells, independent of the other HPV proteins, and the gene profile observed indicates that these effects could be mediated by interactions with cellular proteins. The cellular processes affected suggest that E2 expression leads to the cells in to a convenient environment for a replicative cycle of the virus.

  19. Increased cellular proliferation in rat skeletal muscle and tendon in response to exercise: use of FLT and PET/CT

    DEFF Research Database (Denmark)

    Skovgaard, Dorthe Charlotte; Bayer, Monika L; Mackey, Abigail L;

    2010-01-01

    The purpose of this study is to investigate exercise-induced cellular proliferation in rat skeletal muscle/tendon with the use of 3'-[F-18]fluoro-3'deoxythymidine (FLT) and to quantitatively study concomitant changes in the proliferation-associated factor, Ki67.......The purpose of this study is to investigate exercise-induced cellular proliferation in rat skeletal muscle/tendon with the use of 3'-[F-18]fluoro-3'deoxythymidine (FLT) and to quantitatively study concomitant changes in the proliferation-associated factor, Ki67....

  20. Study on Effect of Aloe Glue on Cytogenetics, Cellular Immunity and Cell Proliferation of Human Cells

    Institute of Scientific and Technical Information of China (English)

    ZHANG Jiahua; WEN Shaluo; XIA Yun; ZHANG Lijun

    2002-01-01

    Objective To provide the scientific evidence for the exploiture of aloe resource. Methods Cytological combined determination was used to study the effect of aloe glue(0.01 ~ 0.3ml) on cytogenetics, cellular immunity and cell proliferation of human cells. Results SCE and MNR in varying dose groups had no significant differences as compared with control group( P > 0.05). LTR was significantly higher than that of control group(P < 0.005). MI was significantly higher than that of control group ( P < 0.05). M3 and PRI in highest dose group had significant differences as compared with control group (P < 0.05). Conclusion Aloe gel had no significant effect on cytogenetics. But it had activating effects on immunity and proliferation of cells.

  1. Radiation-induced changes in cellularity and proliferation in human oral mucosa

    International Nuclear Information System (INIS)

    Purpose: To quantify the oral mucosal cell density and proliferation rate during conventional radiotherapy of head-and-neck tumors and to compare these parameters with clinical scoring of oral mucositis. Methods and Materials: Between 1996 and 1999, 22 patients were included in this study. Mucosal biopsies were taken before or during the radiotherapy course (5 x 2 Gy/wk). Biopsies were incubated in vitro with tritiated thymidine immediately after excision to label DNA-synthesizing cells. Results: Epithelial cell density followed a biphasic radiation response. A steep decrease to about 50% of the preirradiation value (1000 cells/mm epithelium) during Week 1 was followed by a more gradual loss to about 400 cells at the end of treatment. The initial phase was based on the depression of proliferation, with 5-10 labeled cells/mm at the end of Week 1 vs. 60 labeled cells/mm in controls. Subsequently, proliferation was partially restituted at 20 labeled cells/mm. A significant difference in cell numbers was seen between Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer Grade 0 (∼850 cell/mm) and Grade 2 (325/mm) or Grade 3 (370/mm). No significant differences were observed between reaction grades 1, 2, and 3. Conclusion: Conventionally fractionated radiotherapy induces a rapid suppression in cell production in Week 1, which results in a prompt reduction in cell numbers. Subsequently, a partial restoration of proliferation significantly reduces the rate of cell loss. These processes clearly precede the clinical response. Regeneration, defined as restoration of cellularity, is already under way when the maximal clinical response is observed. Clinical reaction grading corresponds poorly to cellular density measures during conventional fractionation

  2. Alteration of the Cyclin D1/p16-pRB Pathway, Cellular Proliferation and Apoptosis in Glioma

    Institute of Scientific and Technical Information of China (English)

    WANGCun-zu; FUZhen; ZHAOZhu.qing

    2004-01-01

    To study the alteration of cyclin D1, p16 and pRB in glioma, analyze proliferation and apoptosis of tmnor cells, and discuss the pathogenesis of glioma, Methods : Thirty-seven glioma specimens were classified as astrocytoma(25 cases, including 7 fibrillary cases; 6 protoplasmic cases; 12 anaplastic cases), and glioblastoma( 12 cases, including 4 GBM cases). Ten normal brain tissues were taken as controls. The expression of cyclin D1, p16 and pRB were detected by imrnunohistochemical method, Cellular proliferation was assessed by Ki-67 label index( Ki-67 LI). Cellular apoptosis was detected by TUNEL and apoptotic indices(AI) was calculated. Resu/ts: The alterations of three proteins were cyclin D1 overexpression( 28/37,75.7% ), p16 and pRB deletion( 20/37.54.1% and 12/37,32.4% ), which were closely related to tumor types, particularly in malignant glioma. Ki-67 LI and AI were higher when pRB pathway was abnormal. Apoptosis was minor in astrocytic tumors( astrocytomas, 0.010±0.002; glioblastomas, 0.057±0.016). Condusion:The abnormalities of cyclin DI/pl6-pRB pathway correlated closely with pathogenesis of glioma.

  3. Arecoline augments cellular proliferation in the prostate gland of male Wistar rats

    International Nuclear Information System (INIS)

    Areca nut chewing is the fourth most popular habit in the world due to its effects as a mild stimulant, causing a feeling of euphoria and slightly heightened alertness. Areca nuts contain several alkaloids and tannins, of which arecoline is the most abundant and known to have several adverse effects in humans, specially an increased risk of oral cancer. On evaluating the effects of arecoline on the male endocrine physiology in Wistar rats, it was found that arecoline treatment led to an overall enlargement and increase in the wet weight of the prostate gland, and a two-fold increase in serum gonadotropin and testosterone levels. Since the prostate is a major target for testosterone, the consequences of arecoline consumption were studied specifically in the prostate gland. Arecoline treatment led to an increase in the number of rough endoplasmic reticulum and reduction of secretory vesicles, signifying a hyperactive state of the prostate. Increased expression of androgen receptors in response to arecoline allowed for enhanced effect of testosterone in the prostate of treated animals, which augmented cell proliferation, subsequently confirmed by an increase in the expression of Ki-67 protein. Cellular proliferation was also the outcome of concomitant over expression of the G1-to-S cell cycle regulatory proteins, cyclin D1 and CDK4, both at the transcriptional and translational levels. Taken together, the findings provide the first evidence that regular use of arecoline may lead to prostatic hyperplasia and hypertrophy, and eventually to disorders associated with prostate enlargement. - Highlights: → Effect of arecoline was investigated on the endocrine physiology of male Wistar rats. → Increase observed in prostate size, wet weight, serum testosterone and gonadotropins. → Arecoline increased RER, expression of androgen receptor and cellular proliferation. → Upregulation of cyclin D1 and CDK4 seen at transcriptional and translational levels. → It may cause

  4. Commonly consumed and specialty dietary mushrooms reduce cellular proliferation in MCF-7 human breast cancer cells.

    Science.gov (United States)

    Martin, Keith R; Brophy, Sara K

    2010-11-01

    Worldwide, over one million women will be newly diagnosed with breast cancer in the next year. Moreover, breast cancer is the second leading cause of cancer death in the USA. An accumulating body of evidence suggests that consumption of dietary mushrooms can protect against breast cancer. In this study, we tested and compared the ability of five commonly consumed or specialty mushrooms to modulate cell number balance in the cancer process using MCF-7 human breast cancer cells. Hot water extracts (80°C for 2 h) of maitake (MT, Grifola frondosa), crimini (CRIM, Agaricus bisporus), portabella (PORT, Agaricus bisporus), oyster (OYS, Pleurotus ostreatus) and white button (WB, Agaricus bisporus) mushrooms or water alone (5% v/v) were incubated for 24 h with MCF-7 cells. Cellular proliferation determined by bromodeoxyuridine incorporation was significantly (P mushrooms, with MT and OYS being the most effective. MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) reduction, an often used mitochondrion-dependent marker of proliferation, was unchanged although decreased (P > 0.05) by 15% with OYS extract. Lactate dehydrogenase release, as a marker of necrosis, was significantly increased after incubation with MT but not with other test mushrooms. Furthermore, MT extract significantly increased apoptosis, or programmed cell death, as determined by terminal deoxynucleotidyl end labeling method, whereas other test mushrooms displayed trends of ∼15%. The total numbers of cells per flask, determined by hemacytometry, were not different from control cultures. Overall, all test mushrooms significantly suppressed cellular proliferation, with MT further significantly inducing apoptosis and cytotoxicity in human breast cancer cells. This suggests that both common and specialty mushrooms may be chemoprotective against breast cancer. PMID:20921274

  5. IL-6 Trans-signaling-STAT3 Pathway Mediates ECM and Cellular Proliferation in Fibroblasts from Hypertrophic Scar

    Science.gov (United States)

    Ray, Sutapa; Ju, Xiaoxi; Sun, Hong; Finnerty, Celeste C; Herndon, David N; Brasier, Allan R

    2012-01-01

    The molecular mechanisms behind the pathogenesis of post-burn hypertrophic scar (HS) remain unclear. Here, we investigate the role of interleukin-6 (IL-6) trans-signaling-STAT3 pathway in HS fibroblasts (HSF) derived from burned-induced HS skin. HSF showed increased Tyr 705 STAT3 phosphorylation over normal fibroblast (NF) after IL-6•IL-6Rα stimulation by immunoassays. The endogenous STAT3 target gene, SOCS3, was upregulated in HSF and showed increased STAT3 binding on its promoter relative to NF in Chromatin Immunoprecipitation assay. We observed that the cell surface signaling transducer glycoprotein 130 is upregulated in HSF using Q-RT-PCR and flow cytometry. The production of excessive extracellular matrix (ECM), including the expression of alpha2 (1) procollagen (Col1A2) and fibronectin 1 (FN) were seen in HSFs. A STAT3 peptide inhibitor abrogated FN and Col1A2 gene expression in HSF indicating involvement of STAT3 in ECM production. The cellular proliferation markers Cyclin D1, Bcl-Xl and c-Myc were also upregulated in HSF and knockdown of STAT3 by siRNA attenuated c-Myc expression indicating the essential role of STAT3 in fibroblast proliferation. Taken together, our results suggest that the IL-6-trans-signaling-STAT3 pathway may play an integral role in HS pathogenesis and disruption of this pathway could be a potential therapeutic strategy for the treatment of burn-induced HS. PMID:23303450

  6. Human papillomavirus type 16 E7 perturbs DREAM to promote cellular proliferation and mitotic gene expression.

    Science.gov (United States)

    DeCaprio, J A

    2014-07-31

    The study of the small DNA tumor viruses continues to provide valuable new insights into oncogenesis and fundamental biological processes. Although much has already been revealed about how the human papillomaviruses (HPVs) can transform cells and contribute to cervical and oropharyngeal cancer, there clearly is much more to learn. In this issue of Oncogene, Pang et al., doi:10.1038/onc.2013.426, demonstrate that the high-risk HPV16 E7 oncogene can promote cellular proliferation by interacting with the DREAM (DP, RB-like, E2F and MuvB) complex at two distinct phases of the cell cycle. Consistent with earlier work, HPV16 E7 can bind to the retinoblastoma tumor suppressor (RB) family member p130 (RBL2) protein and promote its proteasome-mediated destruction thereby disrupting the DREAM complex and can prevent exit from the cell cycle into quiescence. In addition, they demonstrate that HPV16 E7 can bind to MuvB core complex in association with BMYB and FOXM1 and activate gene expression during the G2 and M phase of the cell cycle. Thus, HPV16 E7 acts to prevent exit from the cell cycle entry and promotes mitotic proliferation and may account for the high levels of FOXM1 often observed in poor-risk cervical cancers. PMID:24166507

  7. Human papillomavirus type 16 E7 perturbs DREAM to promote cellular proliferation and mitotic gene expression

    Science.gov (United States)

    DeCaprio, James A.

    2014-01-01

    Study of the small DNA tumor viruses continues to provide valuable new insights into oncogenesis and fundamental biological processes. While much has already been revealed about how the human papillomaviruses (HPVs) can transform cells and contribute to cervical and oropharyngeal cancer, there clearly is much more to learn. In this issue of Oncogene, Pang et al. demonstrate that the high-risk HPV16 E7 oncogene can promote cellular proliferation by interacting with the DREAM (DP, RB-like, E2F and MuvB) complex at two distinct phases of the cell cycle (1). Consistent with earlier work, HPV16 E7 can bind to the retinoblastoma tumor suppressor (RB) family member p130 (RBL2) protein and promote its proteasome-mediated destruction thereby disrupting the DREAM complex and prevent exit from the cell cycle into quiescence. In addition, they demonstrate that HPV16 E7 can bind to MuvB core complex in association with BMYB and FOXM1 and activate gene expression during the G2 and M phase of the cell cycle. Thus, HPV16 E7 acts to prevent exit from the cell cycle entry and promotes mitotic proliferation and may account for the high levels of FOXM1 often observed in poor risk cervical cancers. PMID:24166507

  8. Effect of Irradiation on the Kinetics of Cellular Proliferation in Animal and Human Tumours

    International Nuclear Information System (INIS)

    The kinetics of cellular proliferation in tumours is governed by three main factors, the average duration of the cell cycle, the 'growth fraction' and cell losses. The effect of the last-mentioned factors is the main reason for the variations in rate of growth among solid tumours and for the slackening in the rate of growth observed in a solid tumour as its volume increases. In ascitic tumours the duration of the cell cycle has been found to increase considerably during tumour growth. When a cell is transplanted in the form of an ascitic tumour the mechanisms which explain the gradual slackening of the rate of tumour growth are different from those which obtain when it is grafted in the form of a solid tumour; this shows that these mechanisms depend on extrinsic factors relating to the metabolic conditions,- the cellular micro environment and intercellular contact phenomena. The phenomena which occur in an irradiated tumour are quantitatively similar to those found in normal tissue, but they may differ from the qualitative point of, view and in respect of temporal behaviour. These differences, which doubtless depend on the type of tumour, will have to be analysed before radiotherapy can be used to the maximum advantage. (author)

  9. Regulatory subunits of PKA define an axis of cellular proliferation/differentiation in ovarian cancer cells

    Directory of Open Access Journals (Sweden)

    Hall John C

    2008-09-01

    Full Text Available Abstract Background The regulatory subunit of cAMP-dependent protein kinase (PKA exists in two isoforms, RI and RII, which distinguish the PKA isozymes, type I (PKA-I and type II (PKA-II. Evidence obtained from a variety of different experimental approaches has shown that the relative levels of type I and type II PKA in cells can play a major role in determining the balance between cell growth and differentiation. In order to characterize the effect of PKA type I and type II regulatory subunits on gene transcription at a global level, the PKA regulatory subunit genes for RIα and RIIβ were stably transfected into cells of the ovarian cancer cell line (OVCAR8. Results RIα transfected cells exhibit hyper-proliferative growth and RIIβ transfected cells revert to a relatively quiescent state. Profiling by microarray revealed equally profound changes in gene expression between RIα, RIIβ, and parental OVCAR cells. Genes specifically up-regulated in RIα cells were highly enriched for pathways involved in cell growth while genes up-regulated in RIIβ cells were enriched for pathways involved in differentiation. A large group of genes (~3600 was regulated along an axis of proliferation/differentiation between RIα, parental, and RIIβ cells. RIα/wt and RIIβ/wt gene regulation was shown by two separate and distinct gene set analytical methods to be strongly cross-correlated with a generic model of cellular differentiation. Conclusion Overexpression of PKA regulatory subunits in an ovarian cancer cell line dramatically influences the cell phenotype. The proliferation phenotype is strongly correlated with recently identified clinical biomarkers predictive of poor prognosis in ovarian cancer suggesting a possible pivotal role for PKA regulation in disease progression.

  10. Cellular uptake of 99mTcN-NOET in human leukaemic HL-60 cells is related to calcium channel activation and cell proliferation

    International Nuclear Information System (INIS)

    A major goal of nuclear oncology is the development of new radiolabelled tracers as proliferation markers. Intracellular calcium waves play a fundamental role in the course of the cell cycle. These waves occur in non-excitable tumour cells via store-operated calcium channels (SOCCs). Bis(N-ethoxy, N-ethyldithiocarbamato) nitrido technetium (V)-99m (99mTcN-NOET) has been shown to interact with L-type voltage-operated calcium channels (VOCCs) in cultured cardiomyocytes. Considering the analogy between VOCCs and SOCCs, we sought to determine whether 99mTcN-NOET also binds to activated SOCCs in tumour cells in order to clarify the potential value of this tracer as a proliferation marker. Uptake kinetics of 99mTcN-NOET were measured in human leukaemic HL-60 cells over 60 min and the effect of several calcium channel modulators on 1-min tracer uptake was studied. The uptake kinetics of 99mTcN-NOET were compared both with the variations of cytosolic free calcium concentration measured by indo-1/AM and with the variations in the SG2M cellular proliferation index. All calcium channel inhibitors significantly decreased the cellular uptake of 99mTcN-NOET whereas the activator thapsigargin induced a significant 10% increase. In parallel, SOCC activation by thapsigargin, as measured using the indo-1/AM probe, was inhibited by nicardipine. These results indicate that the uptake of 99mTcN-NOET is related to the activation of SOCCs. Finally, a correlation was observed between the tracer uptake and variations in the proliferation index SG2M. The uptake of 99mTcN-NOET seems to be related to SOCC activation and to cell proliferation in HL-60 cells. These results indicate that 99mTcN-NOET might be a marker of cell proliferation. (orig.)

  11. Telomerase activity is spontaneously increased in lymphocytes from patients with atopic dermatitis and correlates with cellular proliferation

    DEFF Research Database (Denmark)

    Wu, Kehuai; Volke, Anne Rehné; Lund, Marianne;

    1999-01-01

    Telomerase is a ribonucleoprotein enzyme involved with cellular proliferation and cellular senescence. The aim of the present study was to investigate telomerase activity in lymphocytes from patients with atopic dermatitis (AD) and to observe its regulation of cellular proliferation. Peripheral...... staphylococcal enterotoxin A (SEA) (0.1 microg/ml). Telomerase activity was measured by the telomeric repeat amplification protocol-based telomerase polymerase chain reaction enzyme-linked immunosorbent assay at 0 and 72 h of incubation. In addition, DNA synthesis of the cells was assayed using 3H......-thymidine incorporation. We found that telomerase activity in non-stimulated PBMC from patients with AD was significantly up-regulated without any stimulation during the 72 h of in vitro incubation. The most potent stimulator of telomerase activity was SEA, followed by anti-CD3 plus IL-2, anti-CD3 alone, and PPD. IL-2...

  12. Cellular and Molecular Consequences of Peroxisome Proliferator-Activated Receptor-γ Activation in Ovarian Cancer Cells1*

    OpenAIRE

    Vignati, Sara; Albertini, Veronica; Rinaldi, Andrea; Kwee, Ivo; RIVA Cristina; Oldrini, Rita; Capella, Carlo; Bertoni, Francesco; Carbone, Giuseppina M; Catapano, Carlo V.

    2006-01-01

    Peroxisome proliferator-activated receptor-γ (PPAR-γ) is a ligand-activated transcription factor. In addition to its canonical role in lipid and glucose metabolism, PPAR-γ controls cell proliferation, death, and differentiation in several tissues. Here we have examined the expression of PPAR-γ in ovarian tumors and the cellular and molecular consequences of its activation in ovarian cancer cells. PPAR-γ was expressed in a large number of epithelial ovarian tumors and cell lines. The PPAR-γ li...

  13. A dual program for translation regulation in cellular proliferation and differentiation

    DEFF Research Database (Denmark)

    Gingold, Hila; Tehler, Disa; Christoffersen, Nanna R;

    2014-01-01

    A dichotomous choice for metazoan cells is between proliferation and differentiation. Measuring tRNA pools in various cell types, we found two distinct subsets, one that is induced in proliferating cells, and repressed otherwise, and another with the opposite signature. Correspondingly, we found ...

  14. Induction of vascular endothelial phenotype and cellular proliferation from human cord blood stem cells cultured in simulated microgravity

    Science.gov (United States)

    Chiu, Brian; Z-M Wan, Jim; Abley, Doris; Akabutu, John

    2005-05-01

    Recent studies have demonstrated that stem cells derived from adult hematopoietic tissues are capable of trans-differentiation into non-hematopoietic cells, and that the culture in microgravity ( μg) may modulate the proliferation and differentiation. We investigated the application of μg to human umbilical cord blood stem cells (CBSC) in the induction of vascular endothelial phenotype expression and cellular proliferation. CD34+ mononuclear cells were isolated from waste human umbilical cord blood samples and cultured in simulated μg for 14 days. The cells were seeded in rotary wall vessels (RWV) with or without microcarrier beads (MCB) and vascular endothelial growth factor was added during culture. Controls consisted of culture in 1 G. The cell cultures in RWV were examined by inverted microscopy. Cell counts, endothelial cell and leukocyte markers performed by flow-cytometry and FACS scan were assayed at days 1, 4, 7 and at the termination of the experiments. Culture in RWV revealed significantly increased cellular proliferation with three-dimensional (3D) tissue-like aggregates. At day 4, CD34+ cells cultured in RWV bioreactor without MCB developed vascular tubular assemblies and exhibited endothelial phenotypic markers. These data suggest that CD34+ human umbilical cord blood progenitors are capable of trans-differentiation into vascular endothelial cell phenotype and assemble into 3D tissue structures. Culture of CBSC in simulated μg may be potentially beneficial in the fields of stem cell biology and somatic cell therapy.

  15. Feasibility of obtaining breast epithelial cells from healthy women for studies of cellular proliferation.

    Science.gov (United States)

    Miller, N A; Thomas, M; Martin, L J; Hedley, D W; Michal, S; Boyd, N F

    1997-05-01

    Increased dietary fat intake and rate of breast epithelial cell proliferation have each been associated with the development of breast cancer. The goal of this study was to measure the effect of a low fat, high carbohydrate diet on the rate of breast epithelial cell proliferation in women at high risk for breast cancer. Women were recruited from the intervention and control groups of a randomized low fat dietary intervention trial, breast epithelial cells were obtained by fine needle aspiration, and cell proliferation was assessed in these samples using immunofluorescent detection of Ki-67 and PCNA. The effects of needle size and study group on cell yield and cytologic features of the cells were also examined. Fifty three women (20 in the intervention group and 33 in the control group) underwent the biopsy procedure. Slides from 38 subjects were stained for Ki-67 and from 14 subjects for PCNA. No cell proliferation (fluorescence) was detected for either Ki-67 or PCNA in any of the slides. Epithelial cell yield and number of stromal fragments were greater with a larger needle size. Numbers of stromal fragments and bipolar naked nuclei were greater in the low fat as compared to the control group but no differences in epithelial cell yield were observed between the two groups. This study confirms that fine needle aspiration biopsy is a feasible method of obtaining epithelial cells from women without discrete breast masses, but suggests that cell proliferation cannot be assessed using Ki-67 and PCNA in such samples. PMID:9150899

  16. Myocardin inhibits cellular proliferation by inhibiting NF-κB(p65)-dependent cell cycle progression

    OpenAIRE

    Tang, Ru-hang; Zheng, Xi-Long; Callis, Thomas E.; Stansfield, William E.; He, Jiayin; Baldwin, Albert S.; Wang, Da-Zhi; Selzman, Craig H.

    2008-01-01

    We previously reported the importance of the serum response factor (SRF) cofactor myocardin in controlling muscle gene expression as well as the fundamental role for the inflammatory transcription factor NF-κB in governing cellular fate. Inactivation of myocardin has been implicated in malignant tumor growth. However, the underlying mechanism of myocardin regulation of cellular growth remains unclear. Here we show that NF-κB(p65) represses myocardin activation of cardiac and smooth muscle gen...

  17. In-vivo imaging of cellular proliferation in renal cell carcinoma using 18F-fluorothymidine (FLT) PET

    International Nuclear Information System (INIS)

    Full text:Background: The ability to measure cellular proliferation non-invasively in renal cell carcinoma may allow prediction of tumour aggressiveness and response to therapy. The aim of this study was to evaluate the uptake of 18F-fluorothymidine (FLT) in renal cell carcinoma, and to compare this to 18F-fluorodeoxyglucose (FDG), and to an immunohistochemical measure of cellular proliferation (Ki-67). Methods: Twenty seven patients (16 men, 11 women; age 42-77) with newly diagnosed renal cell carcinoma suitable for resection were prospectively enrolled. All patients had preoperative FLT and FDG PET scans. After surgery tumour was taken for histologic analysis and immunohistochemical staining by Ki-67. Results: The mean SUVmax (maximum standardized uptake value) ± SD for FLT in tumour was 2.53 ± 1.26, compared to normal kidney (2.47 ± 0.34). The mean SUVmax for FDG in tumour was similar to FLT (2.60 ± 1.08). Visual identification of tumour using FLT PET compared to normal kidney was facilitated by the use of a pre-operative contrast enhanced CT scan. There was a significant correlation between FLT uptake and the immunohistochemical marker Ki-67 (r=0.624, p=0.0008) in RCC. Ki-67 labelling index was mean ± SD of 13.3% ± 9.2 (range 2.2% to 36.3%). Conclusion: There is detectable uptake of FLT in primary renal cell carcinoma, which correlates with cellular proliferation as assessed by Ki-67 labelling index. This finding has relevance to the use of FLT PET in molecular imaging studies of renal cell carcinoma biology.

  18. Magnolol Affects Cellular Proliferation, Polyamine Biosynthesis and Catabolism-Linked Protein Expression and Associated Cellular Signaling Pathways in Human Prostate Cancer Cells in vitro

    Directory of Open Access Journals (Sweden)

    Brendan T. McKeown

    2015-01-01

    Full Text Available Background: Prostate cancer is the most commonly diagnosed form of cancer in men in Canada and the United States. Both genetic and environmental factors contribute to the development and progression of many cancers, including prostate cancer. Context and purpose of this study: This study investigated the effects of magnolol, a compound found in the roots and bark of the magnolia tree Magnolia officinalis, on cellular proliferation and proliferation-linked activities of PC3 human prostate cancer cells in vitro. Results: PC3 cells exposed to magnolol at a concentration of 80 μM for 6 hours exhibited decreased protein expression of ornithine decarboxylase, a key regulator in polyamine biosynthesis, as well as affecting the expression of other proteins involved in polyamine biosynthesis and catabolism. Furthermore, protein expression of the R2 subunit of ribonucleotide reductase, a key regulatory protein associated with DNA synthesis, was significantly decreased. Finally, the MAPK (mitogen-activated protein kinase, PI3K (phosphatidylinositol 3-kinase, NFκB (nuclear factor of kappa-light-chain-enhancer of activated B cells and AP-1 (activator protein 1 cellular signaling pathways were assayed to determine which, if any, of these pathways magnolol exposure would alter. Protein expressions of p-JNK-1 and c-jun were significantly increased while p-p38, JNK-1/2, PI3Kp85, p-PI3Kp85, p-Akt, NFκBp65, p-IκBα and IκBα protein expressions were significantly decreased. Conclusions: These alterations further support the anti-proliferative effects of magnolol on PC3 human prostate cancer cells in vitro and suggest that magnolol may have potential as a novel anti-prostate cancer agent.

  19. Fish oil supplementation associated with decreased cellular degeneration and increased cellular proliferation 6 weeks after middle cerebral artery occlusion in the rat

    Directory of Open Access Journals (Sweden)

    Pascoe MC

    2015-01-01

    Full Text Available Michaela C Pascoe,1 David W Howells, 2David P Crewther,1 Leeanne M Carey,2,3 Sheila G Crewther4 1Brain Sciences Institute, Swinburne University, ²Florey Institute of Neuroscience and Mental Health, University of Melbourne, 3Department of Occupational Therapy, School of Allied Health La Trobe University, 4School of Psychological Science, La Trobe University, Melbourne, VIC, Australia Abstract: Anti-inflammatory long-chain omega-3 polyunsaturated fatty acids (n-3-LC-PUFAs are both neuroprotective and have antidepressive effects. However the influence of dietary supplemented n-3-LC-PUFAs on inflammation-related cell death and proliferation after middle cerebral artery occlusion (MCAo-induced stroke is unknown. We have previously demonstrated that anxiety-like and hyperactive locomotor behaviors are reduced in n-3-LC-PUFA-fed MCAo animals. Thus in the present study, male hooded Wistar rats were exposed to MCAo or sham surgeries and examined behaviorally 6 weeks later, prior to euthanasia and examination of lesion size, cell death and proliferation in the dentate gyrus, cornu ammonis region of the hippocampus of the ipsilesional hemispheres, and the thalamus of the ipsilesional and contralesional hemispheres. Markers of cell genesis and cell degeneration in the hippocampus or thalamus of the ipsilesional hemisphere did not differ between surgery and diet groups 6 weeks post MCAo. Dietary supplementation with n-3-LC-PUFA decreased cell degeneration and increased cell proliferation in the thalamic region of the contralesional hemisphere. MCAo–associated cell degeneration in the hippocampus and thalamus positively correlated with anxiety-like and hyperactive locomotor behaviors previously reported in these animals. These results suggest that anti-inflammatory n-3-LC-PUFA supplementation appears to have cellular protective effects after MCAo in the rat, which may affect behavioral outcomes. Keywords: apoptosis, polyunsaturated fatty acids

  20. Cellular proliferation in the skin of X-rayed newt limbs (with a note on x-ray-induced limb regression)

    International Nuclear Information System (INIS)

    Left hind limbs, including the pelvis, of adult newts (Notophthalmus viridescens) were locally irradiated with a dose of x-rays that inhibited regeneration (2,000 R). This x-ray dose and other doses (700-2,000 R) capable of inhibiting limb regeneration also cause limb regression prior to amputation. Before limb regression occurred, there was a latent period of 3 to 6 weeks. Limb regression was characterized by necrotic wasting and resorption of distal elements. The degree of loss was variable and dependent upon dosage. After this further degenerative changes were not noted. Proliferation of epidermal cells was examined 4 days after irradiation prior to limb regression or after x-ray-induced degeneration of the limbs had ended. Proliferative activity in x-rayed limbs was also compared at various stages of contralateral control limb regeneration. Limbs examined after x-ray-induced limb regression had ended showed levels of [3H]-thymidine incorporation into DNA comparable to normal epidermis. In contrast, limbs examined 4 days after irradiation had lower levels of DNA synthesis (P much less than 0.01). Amputation of limbs in both groups caused an increase in DNA synthesis (P much less than 0.01). Histological examination showed that cellular proliferation was associated primarily with the epidermis. These results indicate that epidermal cell proliferation was not resistant to x-rays. However, levels of normal cell division were observed after amputation of after cessation of x-ray-induced limb regression

  1. Altered control of cellular proliferation in the absence of mammalian brahma (SNF2alpha).

    Science.gov (United States)

    Reyes, J C; Barra, J; Muchardt, C; Camus, A; Babinet, C; Yaniv, M

    1998-12-01

    The mammalian SWI-SNF complex is an evolutionarily conserved, multi-subunit machine, involved in chromatin remodelling during transcriptional activation. Within this complex, the BRM (SNF2alpha) and BRG1 (SNF2beta) proteins are mutually exclusive subunits that are believed to affect nucleosomal structures using the energy of ATP hydrolysis. In order to characterize possible differences in the function of BRM and BRG1, and to gain further insights into the role of BRM-containing SWI-SNF complexes, the mouse BRM gene was inactivated by homologous recombination. BRM-/- mice develop normally, suggesting that an observed up-regulation of the BRG1 protein can functionally replace BRM in the SWI-SNF complexes of mutant cells. Nonetheless, adult mutant mice were approximately 15% heavier than control littermates. This may be caused by increased cell proliferation, as demonstrated by a higher mitotic index detected in mutant livers. This is supported further by the observation that mutant embryonic fibroblasts were significantly deficient in their ability to arrest in the G0/G1 phase of the cell cycle in response to cell confluency or DNA damage. These studies suggest that BRM participates in the regulation of cell proliferation in adult mice. PMID:9843504

  2. Cellular proliferation and infiltration following interstitial irradiation of normal dog brain is altered by an inhibitor of polyamine synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Fike, J.R.; Gobbel, G.T.; Chou, D. [Univ. of California, San Francisco, CA (United States)] [and others

    1995-07-15

    The objectives of this study were to quantitatively define proliferative and infiltrative cell responses after focal {sup 125}I irradiation of normal brain, and to determine the effects of an intravenous infusion of {alpha}-defluoromethylornithine (DFMO) on those responses. Adult beagle dogs were irradiated using high activity {sup 125}I sources. Cellular responses were quantified using a histomorphometric analysis. After radiation alone, cellular events included a substantial acute inflammatory response followed by increased BrdU labeling and progressive increases in numbers of capillaries and astrocytes. {alpha}-Difluoromethylornithine treatment significantly affected the measured cell responses. As in controls, an early inflammatory response was measured, but after 2 weeks there were more PMNs/unit area than in controls. The onset of measurable BrdU labeling was delayed in DFMO-treated animals, and the magnitude of labeling was significantly reduced. Increases in astrocyte and vessel numbers/mm{sup 2} were observed after a 2-week delay. At the site of implant, astrocytes from DFMO-treated dogs were significantly smaller than those from controls. There is substantial cell proliferation and infiltration in response to interstitial irradiation of normal brain, and these responses are significantly altered by DFMO treatment. Although the precise mechanisms by which DFMO exerts its effects in this model are not known, the results from this study suggest that modification of radiation injury may be possible by manipulating the response of normal cells to injury. 57 refs., 6 figs.

  3. Effects of nicotine on cellular proliferation, cell cycle phase distribution, and macromolecular synthesis in human promyelocytic HL-60 leukaemia cells

    International Nuclear Information System (INIS)

    Addition of nicotine causes a dose- and time-dependent inhibition of cell growth in the human promyelocytic HL-60 leukemia cells, with 4 mM nicotine resulting in a 50% inhibition of cellular proliferation after 48-50h. Accompanying the anticellular effect of nicotine is a significant change in the cell cycle distribution of HL-60 cells. For example, treatment with 4 mM nicotine for 20h causes an increase in the proportion of G1-phase cells (from 49% to 57%) and a significant decrease in the proportion of S-phase cells (from 41% to 32%). These results suggest that nicotine causes partial cell arrest in the G-1 phase which may in part account for its effects on cell growth. To determine whether nicotine changes the cellular uptake/transport to macromolecular precursors, HL-60 cells were treated with 216 mM nicotine for 30h, at the end of which time cells were labelled with (3H)thymidine, (3H)uridine, (14C)lysine and(35S)methionine, the trichloroacetic acid soluble and insoluble radioactivities from each of the labelling conditions were determined. These studies show that nicotine mainly affects the ''de novo synthesis'' of proteins. (author)

  4. HIV aspartyl peptidase inhibitors interfere with cellular proliferation, ultrastructure and macrophage infection of Leishmania amazonensis.

    Directory of Open Access Journals (Sweden)

    Lívia O Santos

    Full Text Available BACKGROUND: Leishmania is the etiologic agent of leishmanisais, a protozoan disease whose pathogenic events are not well understood. Current therapy is suboptimal due to toxicity of the available therapeutic agents and the emergence of drug resistance. Compounding these problems is the increase in the number of cases of Leishmania-HIV coinfection, due to the overlap between the AIDS epidemic and leishmaniasis. METHODOLOGY/PRINCIPAL FINDINGS: In the present report, we have investigated the effect of HIV aspartyl peptidase inhibitors (PIs on the Leishmania amazonensis proliferation, ultrastructure, interaction with macrophage cells and expression of classical peptidases which are directly involved in the Leishmania pathogenesis. All the HIV PIs impaired parasite growth in a dose-dependent fashion, especially nelfinavir and lopinavir. HIV PIs treatment caused profound changes in the leishmania ultrastructure as shown by transmission electron microscopy, including cytoplasm shrinking, increase in the number of lipid inclusions and some cells presenting the nucleus closely wrapped by endoplasmic reticulum resembling an autophagic process, as well as chromatin condensation which is suggestive of apoptotic death. The hydrolysis of HIV peptidase substrate by L. amazonensis extract was inhibited by pepstatin and HIV PIs, suggesting that an aspartyl peptidase may be the intracellular target of the inhibitors. The treatment with HIV PIs of either the promastigote forms preceding the interaction with macrophage cells or the amastigote forms inside macrophages drastically reduced the association indexes. Despite all these beneficial effects, the HIV PIs induced an increase in the expression of cysteine peptidase b (cpb and the metallopeptidase gp63, two well-known virulence factors expressed by Leishmania spp. CONCLUSIONS/SIGNIFICANCE: In the face of leishmaniasis/HIV overlap, it is critical to further comprehend the sophisticated interplays among Leishmania

  5. Cellular proliferation and infiltration following interstitial irradiation of normal dog brain is altered by an inhibitor of polyamine synthesis

    International Nuclear Information System (INIS)

    Purpose: The objectives of this study were to quantitatively define proliferative and infiltrative cell responses after focal 125I irradiation of normal brain, and to determine the effects of an intravenous infusion of α-difluoromethylornithine (DFMO) on those responses. Methods and Materials: Adult beagle dogs were irradiated using high activity 125I sources. Saline (control) or DFMO (150 mg/kg/day) was infused for 18 days starting 2 days before irradiation. At varying times up to 8 weeks after irradiation, brain tissues were collected and the cell responses in and around the focal lesion were quantified. Immunohistochemical stains were used to label astrocytes (GFAP), vascular endothelial cells (Factor VIII), polymorphonuclear leukocytes (PMNs; MAC 387) and cells synthesizing deoxyribonucleic acid (DNA) (BrdU). Cellular responses were quantified using a histomorphometric analysis. Results: After radiation alone, cellular events included a substantial acute inflammatory response followed by increased BrdU labeling and progressive increases in numbers of capillaries and astrocytes. α-Difluoromethylornithine treatment significantly affected the measured cell responses. As in controls, an early inflammatory response was measured, but after 2 weeks there were more PMNs/unit area than in controls. The onset of measurable BrdU labeling was delayed in DFMO-treated animals, and the magnitude of labeling was significantly reduced. Increases in astrocyte and vessel numbers/mm2 were observed after a 2-week delay. At the site of implant, astrocytes from DFMO-treated dogs were significantly smaller than those from controls. Conclusions: There is substantial cell proliferation and infiltration in response to interstitial irradiation of normal brain, and these responses are significantly altered by DFMO treatment. Although the precise mechanisms by which DFMO exerts its effects in this model are not known, the results from this study suggest that modification of radiation

  6. Methods to assess the nucleocytoplasmic shuttling of the HPV E1 helicase and its effects on cellular proliferation and induction of a DNA damage response.

    Science.gov (United States)

    Lehoux, Michaël; Fradet-Turcotte, Amélie; Archambault, Jacques

    2015-01-01

    Replication of the human papillomavirus (HPV) double-stranded DNA genome in the nucleus of infected cells relies on the viral proteins E1 and E2 in conjunction with the host DNA replication machinery. This process is tightly linked to the replication of cellular DNA, in part through the cyclin-dependent phosphorylation of E1, which inhibits its export out of the nucleus to promote its accumulation in this compartment during S-phase. It has been recently shown that accumulation of E1 in the nucleus, while a prerequisite for viral DNA replication, leads to the inhibition of cellular proliferation and the activation of a DNA damage response (DDR). Here we describe methods to monitor the subcellular localization of E1 and to assess the deleterious effects of its nuclear accumulation on cellular proliferation, cell cycle progression and the induction of a DDR, using a combination of colony formation assays, immunofluorescence microcopy, and flow cytometry approaches. PMID:25348298

  7. Effects of nicotine on cellular proliferation, macromolecular synthesis and cell cycle phase distribution in human and murine cells

    International Nuclear Information System (INIS)

    Addition of nicotine causes a dose- and time-dependent inhibition of cell growth in established human and murine cells. In the human promyelocytic HL-60 leukemic cells, 3 mM nicotine results in a 50% inhibition of cellular proliferation after 80 h. Nicotine was also found to affect the cell cycle distribution of HL-60 cells. Treatment with 4 mM nicotine for 20 h causes an increase in proportion of Gl-phase cells (from 49% to 57%) and a significant decrease in the proportion of S-phase cells (from 41% to 32%). These results suggest that nicotine causes cell arrest in the Gl-phase which may in part account for its effects on cell growth. To determine whether nicotine has a primary effect on the uptake/transport of macromolecular precursors into cells, HL-60 cells were treated with 2-6 mM nicotine for 30 h3 at the end of which time cells were labeled with [3H]thymidine, [3H]uridine, [14C]lysine and [35S]methionine, the trichloroacetic acid (TCA) soluble and insoluble radioactivities from each of the labeling conditions were determined. These studies show that nicotine primarily affect the synthesis of proteins

  8. Decreased tumor cell proliferation as an indicator of the effect of preoperative radiotherapy of rectal cancer

    International Nuclear Information System (INIS)

    Background: Rectal cancer is a common malignancy, with significant local recurrence and death rates. Preoperative radiotherapy and refined surgical technique can improve local control rates and disease-free survival. Purpose: To investigate the relationship between the tumor growth fraction in rectal cancer measured with Ki-67 and the outcome, with and without short-term preoperative radiotherapy. Method: Ki-67 (MIB-1) immunohistochemistry was used to measure tumor cell proliferation in the preoperative biopsy and the surgical specimen. Materials: Specimens from 152 patients from the Southeast Swedish Health Care region were included in the Swedish rectal cancer trial 1987-1990. Results: Tumors with low proliferation treated with preoperative radiotherapy had a significantly reduced recurrence rate. The influence on death from rectal cancer was shown only in the univariate analysis. Preoperative radiotherapy of tumors with high proliferation did not significantly improve local control and disease-free survival. The interaction between Ki-67 status and the benefit of radiotherapy was significant for the reduced recurrence rate (p=0.03), with a trend toward improved disease-free survival (p=0.08). In the surgery-alone group, Ki-67 staining did not significantly correlate with local recurrence or survival rates. Conclusion: Many Ki-67 stained tumor cells in the preoperative biopsy predicts an increased treatment failure rate after preoperative radiotherapy of rectal cancer

  9. Spindle assembly checkpoint protein expression correlates with cellular proliferation and shorter time to recurrence in ovarian cancer.

    LENUS (Irish Health Repository)

    McGrogan, Barbara

    2014-07-01

    Ovarian carcinoma (OC) is the most lethal of the gynecological malignancies, often presenting at an advanced stage. Treatment is hampered by high levels of drug resistance. The taxanes are microtubule stabilizing agents, used as first-line agents in the treatment of OC that exert their apoptotic effects through the spindle assembly checkpoint. BUB1-related protein kinase (BUBR1) and mitotic arrest deficient 2 (MAD2), essential spindle assembly checkpoint components, play a key role in response to taxanes. BUBR1, MAD2, and Ki-67 were assessed on an OC tissue microarray platform representing 72 OC tumors of varying histologic subtypes. Sixty-one of these patients received paclitaxel and platinum agents combined; 11 received platinum alone. Overall survival was available for all 72 patients, whereas recurrence-free survival (RFS) was available for 66 patients. Increased BUBR1 expression was seen in serous carcinomas, compared with other histologies (P = .03). Increased BUBR1 was significantly associated with tumors of advanced stage (P = .05). Increased MAD2 and BUBR1 expression also correlated with increased cellular proliferation (P < .0002 and P = .02, respectively). Reduced MAD2 nuclear intensity was associated with a shorter RFS (P = .03), in ovarian tumors of differing histologic subtype (n = 66). In this subgroup, for those women who received paclitaxel and platinum agents combined (n = 57), reduced MAD2 intensity also identified women with a shorter RFS (P < .007). For the entire cohort of patients, irrespective of histologic subtype or treatment, MAD2 nuclear intensity retained independent significance in a multivariate model, with tumors showing reduced nuclear MAD2 intensity identifying patients with a poorer RFS (P = .05).

  10. Changes in the cellularity of the cortex of human hairs as an indicator of radiation exposure

    International Nuclear Information System (INIS)

    Growing hair follicles with their rapid cell proliferation would be expected to be sensitive organs to cytotoxic agents such as radiation. Various abnormalities in the hair and hair follicles have been reported in the past. Changes in the number of cells in the newly forming hair cortex have been shown in the mouse to be one of the more sensitive assays for radiation effects, and this approach could provide a basis for a biological dosimeter. Here we show for the first time using hair cortex cell counts some preliminary data indicating that the number of cell nuclei in a unit of length (140 μm) of the cortex of human hairs from the chest and scalp of patients undergoing fractionated radiotherapy falls significantly (P = 0.005) by 5%-10% 3 days after the first dose in a fractionated sequence of irradiations. The first dose was delivered on a Friday, and no further exposures were delivered until after the hair sample was taken on the 3rd day (Monday). No significant effect of radiation dose could be detected over the available, limited range of doses studied (5 - 6.5 Gy with one exit dose sample at 2.6 Gy). Also, the width varies from hair to hair. If the width of the hair is taken into account and the cortical nuclei counts are normalised to the width of each hair, the effects seen at day 3 become slightly more significant (P = 0.002), and those at day 5 also become significant (P = 0.012). Samples taken on the 5th day after the first (Friday) exposure were also 2 days after the second exposure and 1 day after the third exposure. However, little expression of damage attributable to the 2nd and 3rd exposures was anticipated since their effects would take some time to be expressed in the cortical region examined, which is some distance from the proliferative region of the follicle. (orig.). With 2 figs., 2 tabs

  11. Girdin/GIV is upregulated by cyclic tension, propagates mechanical signal transduction, and is required for the cellular proliferation and migration of MG-63 cells

    International Nuclear Information System (INIS)

    To explore how Girdin/GIV is regulated by cyclic tension and propagates downstream signals to affect cell proliferation and migration. Human osteoblast-like MG-63 cells were exposed to cyclic tension force at 4000 μstrain and 0.5 Hz for 6 h, produced by a four-point bending system. Cyclic tension force upregulated Girdin and Akt expression and phosphorylation in cultured MG-63 cells. Girdin and Akt each promoted the phosphorylation of the other under stimulated tension. In vitro MTT and transwell assays showed that Girdin and Akt are required for cell proliferation and migration during cellular quiescence. Moreover, STAT3 was determined to be essential for Girdin expression under stimulated tension force in the physiological condition, as well as for osteoblast proliferation and migration during quiescence. These findings suggest that the STAT3/Girdin/Akt pathway activates in osteoblasts in response to mechanical stimulation and may play a significant role in triggering osteoblast proliferation and migration during orthodontic treatment. - Highlights: • Tension force upregulates Girdin and Akt expression and phosphorylation. • Girdin and Akt promotes the phosphorylation of each other under tension stimulation. • Girdin and Akt are required for MG-63 cell proliferation and migration. • STAT3 is essential for Girdin expression after application of the tension forces

  12. Girdin/GIV is upregulated by cyclic tension, propagates mechanical signal transduction, and is required for the cellular proliferation and migration of MG-63 cells

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Jiang-Tian; Li, Yan; Yu, Bing; Gao, Guo-Jie; Zhou, Ting; Li, Song, E-mail: song_li59@126.com

    2015-08-21

    To explore how Girdin/GIV is regulated by cyclic tension and propagates downstream signals to affect cell proliferation and migration. Human osteoblast-like MG-63 cells were exposed to cyclic tension force at 4000 μstrain and 0.5 Hz for 6 h, produced by a four-point bending system. Cyclic tension force upregulated Girdin and Akt expression and phosphorylation in cultured MG-63 cells. Girdin and Akt each promoted the phosphorylation of the other under stimulated tension. In vitro MTT and transwell assays showed that Girdin and Akt are required for cell proliferation and migration during cellular quiescence. Moreover, STAT3 was determined to be essential for Girdin expression under stimulated tension force in the physiological condition, as well as for osteoblast proliferation and migration during quiescence. These findings suggest that the STAT3/Girdin/Akt pathway activates in osteoblasts in response to mechanical stimulation and may play a significant role in triggering osteoblast proliferation and migration during orthodontic treatment. - Highlights: • Tension force upregulates Girdin and Akt expression and phosphorylation. • Girdin and Akt promotes the phosphorylation of each other under tension stimulation. • Girdin and Akt are required for MG-63 cell proliferation and migration. • STAT3 is essential for Girdin expression after application of the tension forces.

  13. The effects of short-chain fatty acids on colon epithelial proliferation and survival depend on the cellular phenotype.

    OpenAIRE

    Comalada, Monica; Bailon, Elvira; de Haro, Oscar; Lara-Villoslada, Federico; Xaus, Jordi; Zarzuelo, Antonio; Galvez, Julio

    2006-01-01

    Dietary modulation of cancer & cancer biomarkers. Dietary item or component studied: short-chain fatty acids (SCFA)Outcome studied: proliferation rate and apoptosis in the adenocarcinoma cells; proliferation rate and regeneration of intestinal epithelial cells. Study type: human colon adenocarninoma cells (HT-29); fetal human normal colon cells (FHC); Female Wistar rats Tissue/biological material/sample size: rat colon. Mode of exposure: dietary. Impact on outcome (including dose-response):in...

  14. Might carnitine status in animals indicate environmental/toxicological harm at the cellular level?

    Energy Technology Data Exchange (ETDEWEB)

    Garst, J.E.

    1995-12-01

    It is well known that R-(L)-carnitine (Cn) is essential for the energy-producing, mitochondrial beta-oxidation of long chain fatty acids. Cn can ameliorate the diverse effects of drugs, a chemicals and pollutants. Moreover, the toxicities of carbon monoxide, several heavy metals, and even the antibiotic cephaloridine seem mediated, in part, by actions affecting the Cn system. Data which could suggest that the Cn system is an integrator/regulator of the cellular response by the organism to it`s environment is described.

  15. PUMILIO-2 is involved in the positive regulation of cellular proliferation in human adipose-derived stem cells.

    Science.gov (United States)

    Shigunov, Patrícia; Sotelo-Silveira, Jose; Kuligovski, Crisciele; de Aguiar, Alessandra Melo; Rebelatto, Carmen K; Moutinho, José A; Brofman, Paulo S; Krieger, Marco A; Goldenberg, Samuel; Munroe, David; Correa, Alejandro; Dallagiovanna, Bruno

    2012-01-20

    Stem cells can either differentiate into more specialized cells or undergo self-renewal. Several lines of evidence from different organisms suggest that these processes depend on the post-transcriptional regulation of gene expression. The presence of the PUF [Pumilio/FBF (fem-3 binding factor)] domain defines a conserved family of RNA binding proteins involved in repressing gene expression. It has been suggested that a conserved function of PUF proteins is to repress differentiation and sustain the mitotic proliferation of stem cells. In humans, Pumilio-2 (PUM2) is expressed in embryonic stem cells and adult germ cells. Here we show that PUM2 is expressed in a subpopulation of adipose-derived stem cell (ASC) cultures, with a granular pattern of staining in the cytoplasm. Protein levels of PUM2 showed no changes during the differentiation of ASCs into adipocytes. Moreover, RNAi knockdown of pum2 did not alter the rate of adipogenic differentiation compared with wild-type control cells. A ribonomic approach was used to identify PUM2-associated mRNAs. Microarray analysis showed that PUM2-bound mRNAs are part of gene networks involved in cell proliferation and gene expression control. We studied pum2 expression in cell cultures with low or very high levels of proliferation and found that changes in pum2 production were dependent on the proliferation status of the cell. Transient knockdown of pum2 expression by RNAi impaired proliferation of ASCs in vitro. Our results suggest that PUM2 does not repress differentiation of ASCs but rather is involved in the positive control of ASCs division and proliferation. PMID:21649561

  16. Identification of irradiated food. III. Identification of irradiated potato tubers by means of a test based on the cellular proliferation

    International Nuclear Information System (INIS)

    The effect of gamma radiation on the formation of the wound periderm in potato tubers cut in halves and on the proliferation of the potato parenchyma cultivated ''in vitro'' is studied. Doses of 3 Krad and higher ones completely inhibit the formation of the wound periderm and the growth of protuberances in the fragments of the parenchyma cultivated ''in vitro''. In the control and IPC treated tubers the proliferation was normal and abundant, in the tubers as well as in the potato parenchyma tissues cultivated ''in vitro''.(author)

  17. Androgen Receptor Expression and Cellular Proliferation During Transition from Androgen-Dependent to Recurrent Growth after Castration in the CWR22 Prostate Cancer Xenograft

    OpenAIRE

    Kim, Desok; Gregory, Christopher W.; French, Frank S.; Smith, Gary J.; Mohler, James L.

    2002-01-01

    Androgen receptor expression was analyzed in the CWR22 human prostate cancer xenograft model to better understand its role in prostate cancer recurrence after castration. In androgen-dependent tumors, 98.5% of tumor cell nuclei expressed androgen receptor with a mean optical density of 0.26 ± 0.01. On day 2 after castration androgen deprivation decreased immunostained cells to 2% that stained weakly (mean optical density, 0.16 ± 0.08). Cellular proliferation measured using Ki-67 revealed

  18. Musashi1 regulates breast tumor cell proliferation and is a prognostic indicator of poor survival

    Directory of Open Access Journals (Sweden)

    Wang Xiao-Yang

    2010-08-01

    Full Text Available Abstract Background Musashi1 (Msi1 is a conserved RNA-binding protein that regulates the Notch and Wnt pathways, and serves as a stem cell marker in the breast and other tissues. It is unknown how Msi1 relates to other breast cancer markers, whether it denotes tumor initiating cells (TICs, and how it affects gene expression and tumor cell survival in breast cancer cells. Results Msi1 expression was analyzed in 20 breast cancer cell lines and in 140 primary breast tumors by western blotting and immunohistochemistry, respectively. Lentivirus RNA interference was used to reduce Msi1 expression in breast cancer cell lines MCF-7 and T47D grown as spheroid cultures and to assess stem cell gene expression and the growth of these cell lines as xenografts. In normal human breast tissue, Msi1 was expressed in 10.6% of myoepithelum and 1.2% of ductal epithelium in the terminal ductal lobular unit (TDLU, whereas, less than 0.05% of ductal epithelium and myoepithelium in large ducts outside the TDLU expressed Msi1. Msi1 was expressed in 55% of the breast cancer cell lines and correlated with ErbB2 expression in 50% of the cell lines. Msi1 was expressed in 68% of primary tumors and in 100% of lymph node metastases, and correlated with 5 year survival. Msi1 was enriched in CD133+ MCF-7 and T47D cells and in spheroid cultures of these cells, and Msi1 'knockdown' (KD with a lentivirus-expressed shRNA decreased the number and size of spheroid colonies. Msi1 KD reduced Notch1, c-Myc, ErbB2 and pERK1/2 expression, and increased p21CIP1 expression, which is consistent with known Msi1 target mRNAs. Msi1 KD also reduced the expression of the somatic and embryonic stem cell markers, CD133, Bmi1, Sox2, Nanog and Oct4. Xenografts of MCF-7 and T47D Msi1 KD cells resulted in a marked reduction of tumor growth, reduced Msi1 and Notch1 expression and increased p21CIP1 expression. Conclusion Msi1 is a negative prognostic indicator of breast cancer patient survival, and is

  19. FGF-10 and specific structural elements of dermatan sulfate size and sulfation promote maximal keratinocyte migration and cellular proliferation

    OpenAIRE

    Radek, Katherine A.; Taylor, Kristen R.; Gallo, Richard L

    2009-01-01

    Fibroblast growth factor-10 (FGF-10) is essential for epithelial development, while other members of this family, such as FGF-7, are not. FGF-10 is abundantly released into wounds following injury, and likely an essential growth factor required for this process. To evaluate how activation of this growth factor is controlled, multiple glycosaminoglycans were combined with FGF-10 assayed by measurement of the proliferation of cell lines expressing FGF receptor-2-IIIb, or keratinocyte migration ...

  20. Store-Operated Ca2+ Entry Does Not Control Proliferation in Primary Cultures of Human Metastatic Renal Cellular Carcinoma

    Directory of Open Access Journals (Sweden)

    Silvia Dragoni

    2014-01-01

    Full Text Available Store-operated Ca2+ entry (SOCE is activated following depletion of the inositol-1,4,5-trisphosphate (InsP3-sensitive Ca2+ pool to regulate proliferation in immortalized cell lines established from either primary or metastatic lesions. The molecular nature of SOCE may involve both Stim1, which senses Ca2+ levels within the endoplasmic reticulum (ER Ca2+ reservoir, and a number of a Ca2+-permeable channels on the plasma membrane, including Orai1, Orai3, and members of the canonical transient receptor (TRPC1–7 family of ion channels. The present study was undertaken to assess whether SOCE is expressed and controls proliferation in primary cultures isolated from secondary lesions of heavily pretreated metastatic renal cell carcinoma (mRCC patients. SOCE was induced following pharmacological depletion of the ER Ca2+ store, but not by InsP3-dependent Ca2+ release. Metastatic RCC cells express Stim1-2, Orai1–3, and TRPC1–7 transcripts and proteins. In these cells, SOCE was insensitive to BTP-2, 10 µM Gd3+ and Pyr6, while it was inhibited by 100 µM Gd3+, 2-APB, and carboxyamidotriazole (CAI. Neither Gd3+ nor 2-APB or CAI impaired mRCC cell proliferation. Consistently, no detectable Ca2+ signal was elicited by growth factor stimulation. Therefore, a functional SOCE is expressed but does not control proliferation of mRCC cells isolated from patients resistant to multikinase inhibitors.

  1. Short- and long-term biomarkers for bacterial robustness: a framework for quantifying correlations between cellular indicators and adaptive behavior.

    Directory of Open Access Journals (Sweden)

    Heidy M W den Besten

    Full Text Available The ability of microorganisms to adapt to changing environments challenges the prediction of their history-dependent behavior. Cellular biomarkers that are quantitatively correlated to stress adaptive behavior will facilitate our ability to predict the impact of these adaptive traits. Here, we present a framework for identifying cellular biomarkers for mild stress induced enhanced microbial robustness towards lethal stresses. Several candidate-biomarkers were selected by comparing the genome-wide transcriptome profiles of our model-organism Bacillus cereus upon exposure to four mild stress conditions (mild heat, acid, salt and oxidative stress. These candidate-biomarkers--a transcriptional regulator (activating general stress responses, enzymes (removing reactive oxygen species, and chaperones and proteases (maintaining protein quality--were quantitatively determined at transcript, protein and/or activity level upon exposure to mild heat, acid, salt and oxidative stress for various time intervals. Both unstressed and mild stress treated cells were also exposed to lethal stress conditions (severe heat, acid and oxidative stress to quantify the robustness advantage provided by mild stress pretreatment. To evaluate whether the candidate-biomarkers could predict the robustness enhancement towards lethal stress elicited by mild stress pretreatment, the biomarker responses upon mild stress treatment were correlated to mild stress induced robustness towards lethal stress. Both short- and long-term biomarkers could be identified of which their induction levels were correlated to mild stress induced enhanced robustness towards lethal heat, acid and/or oxidative stress, respectively, and are therefore predictive cellular indicators for mild stress induced enhanced robustness. The identified biomarkers are among the most consistently induced cellular components in stress responses and ubiquitous in biology, supporting extrapolation to other microorganisms

  2. Inhibition of cellular proliferation by the Wilms tumor suppressor WT1 requires association with the inducible chaperone Hsp70

    OpenAIRE

    Maheswaran, Shyamala; Englert, Christoph; Zheng, Gang; Lee, Sean Bong; Wong, Jenise; Harkin, D Paul; Bean, James; Ezzell, Robert; Garvin, A. Julian; McCluskey, Robert T.; DeCaprio, James A.; Haber, Daniel A.

    1998-01-01

    The Wilms tumor suppressor WT1 encodes a zinc finger transcription factor that is expressed in glomerular podocytes during a narrow window in kidney development. By immunoprecipitation and protein microsequencing analysis, we have identified a major cellular protein associated with endogenous WT1 to be the inducible chaperone Hsp70. WT1 and Hsp70 are physically associated in embryonic rat kidney cells, in primary Wilms tumor specimens and in cultured cells with inducible expression of WT1. Co...

  3. Effects of octreotide and insulin on colon cancer cellular proliferation and correlation with hTERT activity

    OpenAIRE

    Ayiomamitis, Georgios D.; Notas, George; Zaravinos, Apostolos; Drygiannakis, Ioannis; Georgiadou, Maria; Sfakianaki, Ourania; Mastrodimou, Niki; Thermos, Kyriaki; Kouroumalis, Elias

    2014-01-01

    Peptide hormone somatostatin and its receptors have a wide range of physiological functions and play a role in the treatment of numerous human diseases, including colorectal cancer. Octreotide, a synthetic somatostatin-analog peptide, inhibits growth of colonic cancer cells primarily by binding to G-protein coupled receptors and elicits cellular responses through second-messenger systems. Insulin also initiates mitogenic signals in certain cell types. The objective of the present study was to...

  4. Indicators of environmental stress: cellular biomarkers and reproductive responses in the Sydney rock oyster (Saccostrea glomerata).

    Science.gov (United States)

    Edge, Katelyn J; Johnston, Emma L; Roach, Anthony C; Ringwood, Amy H

    2012-07-01

    We measured a suite of common biomarker responses for the first time in the Sydney rock oyster Saccostrea glomerata to evaluate their utility as biological effects measures for pollution monitoring. To examine the relationship between biomarker responses and population level effects, fertilisation and embryo development assays were also conducted. Adult oysters were deployed in two contaminated estuaries and a reference estuary in Sydney, Australia. The concentrations of various contaminants (metals and polycyclic aromatic hydrocarbon, PAHs) were quantified in oyster's tissue from each site and both metals and total PAHs were significantly elevated in contaminated estuaries relative to the reference estuary. Lysosomal membrane destabilisation, lipid peroxidation levels and glutathione (GSH) concentrations were measured in the digestive gland of oysters. Of all biomarkers measured, lysosomal membrane destabilisation proved to be the most useful indicator of oysters facing anthropogenic stress and we suggest this may be an especially useful biomarker for incorporation into local environmental monitoring programs. Moreover, lysosomal membrane destabilisation showed good correlations with fertilisation, normal embryo development and estuary status. GSH and lipid peroxidation were not as valuable for distinguishing between estuaries exposed to differing levels of anthropogenic stress, but did provide additional valuable information regarding overall health status of the oysters. PMID:22526923

  5. Imaging of cellular proliferation in liver metastasis by [18F]fluorothymidine positron emission tomography: effect of therapy

    International Nuclear Information System (INIS)

    Although [18F]fluorothymidine positron emission tomography (FLT-PET) permits estimation of tumor thymidine kinase-1 expression, and thus, cell proliferation, high physiological uptake of tracer in liver tissue can limit its utility. We evaluated FLT-PET combined with a temporal-intensity information-based voxel-clustering approach termed kinetic spatial filtering (FLT-PETKSF) for detecting drug response in liver metastases. FLT-PET and computed tomography data were collected from patients with confirmed breast or colorectal liver metastases before, and two weeks after the first cycle of chemotherapy. Changes in tumor FLT-PET and FLT-PETKSF variables were determined. Visual distinction between tumor and normal liver was seen in FLT-PETKSF images. Of the 33 metastases from 20 patients studied, 26 were visible after kinetic filtering. The net irreversible retention of the tracer (Ki; from unfiltered data) in the tumor, correlated strongly with tracer uptake when the imaging variable was an unfiltered average or maximal standardized uptake value, 60 min post-injection (SUV60,av: r = 0.9, SUV60,max: r = 0.7; p KSF (r = 0.7, p KSF detected changes in proliferation in liver metastases. (paper)

  6. Fatty acid synthase as a factor required for exercise-induced cognitive enhancement and dentate gyrus cellular proliferation.

    Directory of Open Access Journals (Sweden)

    Nataliya E Chorna

    Full Text Available Voluntary running is a robust inducer of adult hippocampal neurogenesis. Given that fatty acid synthase (FASN, the key enzyme for de novo fatty acid biosynthesis, is critically involved in proliferation of embryonic and adult neural stem cells, we hypothesized that FASN could mediate both exercise-induced cell proliferation in the subgranular zone (SGZ of the dentate gyrus (DG and enhancement of spatial learning and memory. In 20 week-old male mice, voluntary running-induced hippocampal-specific upregulation of FASN was accompanied also by hippocampal-specific accumulation of palmitate and stearate saturated fatty acids. In experiments addressing the functional role of FASN in our experimental model, chronic intracerebroventricular (i.c.v. microinfusions of C75, an irreversible FASN inhibitor, and significantly impaired exercise-mediated improvements in spatial learning and memory in the Barnes maze. Unlike the vehicle-injected mice, the C75 group adopted a non-spatial serial escape strategy and displayed delayed escape latencies during acquisition and memory tests. Furthermore, pharmacologic blockade of FASN function with C75 resulted in a significant reduction, compared to vehicle treated controls, of the number of proliferative cells in the DG of running mice as measured by immunoreactive to Ki-67 in the SGZ. Taken together, our data suggest that FASN plays an important role in exercise-mediated cognitive enhancement, which might be associated to its role in modulating exercise-induced stimulation of neurogenesis.

  7. Study the Effect of Echinacea Purpurea Extract on Cellular Delayed Type Hypersensitivity and Splenocyte Proliferation in BALB/c Mice

    Directory of Open Access Journals (Sweden)

    Z.M. Hassan

    2008-01-01

    Full Text Available Objective: Purple cone flower plant (Echinacea purpurea is one of the mostimportant Herbal products in many countries. Up to now a lot of experimentsdemonstrated the controversial effects of this herb on immune system . In thisresearch we study the in vivo and in vitro effect of Iranian E.purpurea extract oncellular immunity.Materials and Methods: At first we determined the lethal dose of E.purpurea extract after intraperitoneal injection in BALB/c mice. Then we made five groups of mice and treat them by four times intraperitoneal injection of 1 ml extract at different doses (0, 0.4, 2, 10 and 50 mg/ml during two weeks. Splenocyte proliferation response to extract was assessed by MTT method. Delayed-Type Hypersensitivity (DTHresponse was evaluated by priming mice with 1×108 Sheep Red Blood Cell (SRBC injected subcutaneously in the back on day 7after treatment.Results: As a result no significant variation in weight and spleen index of test groups to control was observed. Splenocyte proliferation and DTH response of test groups to control increased significantly (p<0.05.Conclusion: However these data confirmed the results of previous studies, inaddition presented the first results about significant increase in DTH response that could not be seen before. Scince the main reason of this difference refers to active compounds of herb extract, comparing effective component of this extract with that of E.purpurea cultivated in other geographical condition will consider as the next studies.

  8. Proliferation of germ cells and somatic cells in first trimester human embryonic gonads as indicated by S and S+G2+M phase fractions

    DEFF Research Database (Denmark)

    Sørensen, K P; Lutterodt, M C; Mamsen, L S;

    2011-01-01

    The number of germ cells and somatic cells in human embryonic and foetal gonads has previously been estimated by stereological methods, which are time- and labour-consuming with little information concerning cell proliferation. Here, we studied whether flow cytometry could be applied as an easier...... method, also enabling estimation of the fraction of cells in S or S+G(2)+M (SG(2) M) cell-cycle phases as indicators of cell proliferation....

  9. The human angiotensin AT(1) receptor supports G protein-independent extracellular signal-regulated kinase 1/2 activation and cellular proliferation

    DEFF Research Database (Denmark)

    Hansen, Jakob Lerche; Aplin, Mark; Hansen, Jonas Tind; Christensen, Gitte Lund; Bonde, Marie Mi; Schneider, Mikael; Haunsø, Stig; Schiffer, Hans H; Burstein, Ethan S; Weiner, David M; Sheikh, Søren P

    AT(1) receptor signalling is illustrated by the common use of angiotensin AT(1) receptor-inverse agonists in clinical practice. It is well established that rodent orthologues of the angiotensin AT(1) receptor can selectively signal through G protein-dependent and -independent mechanisms in......(1) receptor actions. However, it is currently unknown whether the human angiotensin AT(1) receptor can signal through G protein-independent mechanisms - and if so, what the physiological impact of such signalling is. We have performed a detailed pharmacological analysis of the human angiotensin AT(1......) receptor using a battery of angiotensin analogues and registered drugs targeting this receptor. We show that the human angiotensin AT(1) receptor signals directly through G protein-independent pathways and supports NIH3T3 cellular proliferation. The realization of G protein-independent signalling by the...

  10. The cellular prion protein PrP(c is involved in the proliferation of epithelial cells and in the distribution of junction-associated proteins.

    Directory of Open Access Journals (Sweden)

    Etienne Morel

    Full Text Available BACKGROUND: The physiological function of the ubiquitous cellular prion protein, PrP(c, is still under debate. It was essentially studied in nervous system, but poorly investigated in epithelial cells. We previously reported that PrP(c is targeted to cell-cell junctions of polarized epithelial cells, where it interacts with c-Src. METHODOLOGY/FINDINGS: We show here that, in cultured human enterocytes and in intestine in vivo, the mature PrP(c is differentially targeted either to the nucleus in dividing cells or to cell-cell contacts in polarized/differentiated cells. By proteomic analysis, we demonstrate that the junctional PrP(c interacts with cytoskeleton-associated proteins, such as gamma- and beta-actin, alpha-spectrin, annexin A2, and with the desmosome-associated proteins desmoglein, plakoglobin and desmoplakin. In addition, co-immunoprecipitation experiments revealed complexes associating PrP(c, desmoglein and c-Src in raft domains. Through siRNA strategy, we show that PrP(c is necessary to complete the process of epithelial cell proliferation and for the sub-cellular distribution of proteins involved in cell architecture and junctions. Moreover, analysis of the architecture of the intestinal epithelium of PrP(c knock-out mice revealed a net decrease in the size of desmosomal junctions and, without change in the amount of BrdU incorporation, a shortening of the length of intestinal villi. CONCLUSIONS/SIGNIFICANCE: From these results, PrP(c could be considered as a new partner involved in the balance between proliferation and polarization/differentiation in epithelial cells.

  11. Reversible one-dimensional cellular automata with one of the two Welch indices equal to 1 and full shifts

    International Nuclear Information System (INIS)

    Reversible cellular automata are invertible discrete dynamical systems which have been widely studied both for analysing interesting theoretical questions and for obtaining relevant practical applications, for instance, simulating invertible natural systems or implementing data coding devices. An important problem in the theory of reversible automata is to know how the local behaviour which is not invertible is able to yield a reversible global one. In this sense, symbolic dynamics plays an important role for obtaining an adequate representation of a reversible cellular automaton. In this paper we prove the equivalence between a reversible automaton where the ancestors only differ at one side (technically with one of the two Welch indices equal to 1) and a full shift. We represent any reversible automaton by a de Bruijn diagram, and we characterize the way in which the diagram produces an evolution formed by undefined repetitions of two states. By means of amalgamations, we prove that there is always a way of transforming a de Bruijn diagram into the full shift. Finally, we provide an example illustrating the previous results

  12. Accumulated SET protein up-regulates and interacts with hnRNPK, increasing its binding to nucleic acids, the Bcl-xS repression, and cellular proliferation

    Energy Technology Data Exchange (ETDEWEB)

    Almeida, Luciana O.; Garcia, Cristiana B.; Matos-Silva, Flavia A. [Department of Clinical Analyses, Toxicology and Food Sciences, School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP (Brazil); Curti, Carlos [Department of Physics and Chemistry, School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP (Brazil); Leopoldino, Andréia M., E-mail: andreiaml@usp.br [Department of Clinical Analyses, Toxicology and Food Sciences, School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP (Brazil)

    2014-02-28

    Highlights: • hnRNPK is a new target of SET. • SET regulates hnRNPK. • SET and hnRNPK accumulation promotes tumorigenesis. • SET accumulation is a potential model to study genes regulated by SET-hnRNPK. - Abstract: SET and hnRNPK are proteins involved in gene expression and regulation of cellular signaling. We previously demonstrated that SET accumulates in head and neck squamous cell carcinoma (HNSCC); hnRNPK is a prognostic marker in cancer. Here, we postulate that SET and hnRNPK proteins interact to promote tumorigenesis. We performed studies in HEK293 and HNSCC (HN6, HN12, and HN13) cell lines with SET/hnRNPK overexpression and knockdown, respectively. We found that SET and/or hnRNPK protein accumulation increased cellular proliferation. SET accumulation up-regulated hnRNPK mRNA and total/phosphorylated protein, promoted hnRNPK nuclear location, and reduced Bcl-x mRNA levels. SET protein directly interacted with hnRNPK, increasing both its binding to nucleic acids and Bcl-xS repression. We propose that hnRNPK should be a new target of SET and that SET–hnRNPK interaction, in turn, has potential implications in cell survival and malignant transformation.

  13. The bradykinin B2 receptor induces multiple cellular responses leading to the proliferation of human renal carcinoma cell lines

    International Nuclear Information System (INIS)

    The vasoactive peptide bradykinin (BK) acts as a potent growth factor for normal kidney cells, but there have been few studies on the role of BK in renal cell carcinomas. In this study, we tested the hypothesis that BK also acts as a mitogen in kidney carcinomas, and explored the effects of BK in human renal carcinoma A498 cells. The presence of mRNAs for BK B1 and BK B2 receptors in A498 cells was demonstrated by reverse transcription–polymerase chain reaction. To study BK signaling pathways, we employed fluorescent measurements of intracellular Ca2+, measured changes in extracellular pH as a reflection of Na+/H+ exchange (NHE) with a Cytosensor microphysiometer, and assessed extracellular signal-regulated kinase (ERK) activation by Western blotting. Exposure to 100 nM of BK resulted in the rapid elevation of intracellular Ca2+, caused a ≥30% increase in NHE activity, and a ≥300% increase in ERK phosphorylation. All BK signals were blocked by HOE140, a BK B2 receptor antagonist, but not by a B1 receptor antagonist. Inhibitor studies suggest that BK-induced ERK activation requires phospholipase C and protein kinase C activities, and is Ca2+/calmodulin-dependent. The amiloride analog 5-(N-methyl-N-isobutyl)-amiloride (MIA) blocked short-term NHE activation and inhibited ERK phosphorylation, suggesting that NHE is critical for ERK activation by BK. BK induced an approximately 40% increase in the proliferation of A498 cells as assessed by bromodeoxyuridine uptake. This effect was blocked by the ERK inhibitor PD98059, and was dependent on NHE activity. We conclude that BK exerts mitogenic effects in A498 cells via the BK B2 receptor activation of growth-associated NHE and ERK

  14. A chimera embryo assay reveals a decrease in embryonic cellular proliferation induced by sperm from X-irradiated male mice

    International Nuclear Information System (INIS)

    Male mice were divided into three experimental groups and a control group. Mice in the experimental groups received one of three doses of acute X irradiation (1.73, 0.29, and 0.05 Gy) and together with the control unirradiated mice were then mated weekly to unirradiated female mice for a 9-week experimental period. Embryos were recovered from the weekly matings at the four-cell stage and examined by the chimera assay for proliferative disadvantage. Aggregation chimeras were constructed of embryos from female mice mated to irradiated males (experimental embryos) and embryos from females mated to unexposed males (control embryos) and contained either one experimental embryo and one control embryo (heterologous chimera) or two control embryos (control chimera). The control embryo in heterologous chimeras and either embryo in control chimeras were prelabeled with the vital dye fluorescein isothiocyanate (FITC), and the chimeras were cultured for 40 h and viewed under phase-contrast and epifluorescence microscopy to obtain total embryo cell number and the cellular contribution from the FITC-labeled embryo. Experimental and control embryos that were cultured singly were also examined for embryo cell number at the end of the 40-h culture period. In control chimeras, the mean ratio of the unlabeled cells:total chimera cell number (henceforth referred to as ''mean ratio'') was 0.50 with little or no weekly variation over the 9-week experimental period. During Weeks 4-7, the mean ratios of heterologous chimeras differed significantly from the mean ratio of control chimeras with the greatest differences occurring during Week 7 (0.41 for chimeras of 0.05 Gy dose group, 0.40 for chimeras of the 0.29 Gy dose group, and 0.17 for chimeras of the 1.73 Gy dose group)

  15. The bradykinin B2 receptor induces multiple cellular responses leading to the proliferation of human renal carcinoma cell lines

    Directory of Open Access Journals (Sweden)

    Kramarenko II

    2012-07-01

    Full Text Available Inga I Kramarenko1, Thomas A Morinelli1,2, Marlene A Bunni1,2, John R Raymond Sr3, Maria N Garnovskaya11Department of Medicine (Nephrology Division, Medical University of South Carolina, Charleston, SC, USA; 2Medical and Research Services of the Ralph H Johnson Veterans Affairs Medical Center, Charleston, SC, USA; 3Medical College of Wisconsin, Milwaukee, WI, USABackground: The vasoactive peptide bradykinin (BK acts as a potent growth factor for normal kidney cells, but there have been few studies on the role of BK in renal cell carcinomas.Purpose: In this study, we tested the hypothesis that BK also acts as a mitogen in kidney carcinomas, and explored the effects of BK in human renal carcinoma A498 cells.Methods: The presence of mRNAs for BK B1 and BK B2 receptors in A498 cells was demonstrated by reverse transcription–polymerase chain reaction. To study BK signaling pathways, we employed fluorescent measurements of intracellular Ca2+, measured changes in extracellular pH as a reflection of Na+/H+ exchange (NHE with a Cytosensor microphysiometer, and assessed extracellular signal-regulated kinase (ERK activation by Western blotting.Results: Exposure to 100 nM of BK resulted in the rapid elevation of intracellular Ca2+, caused a ≥30% increase in NHE activity, and a ≥300% increase in ERK phosphorylation. All BK signals were blocked by HOE140, a BK B2 receptor antagonist, but not by a B1 receptor antagonist. Inhibitor studies suggest that BK-induced ERK activation requires phospholipase C and protein kinase C activities, and is Ca2+/calmodulin-dependent. The amiloride analog 5-(N-methyl-N-isobutyl-amiloride (MIA blocked short-term NHE activation and inhibited ERK phosphorylation, suggesting that NHE is critical for ERK activation by BK. BK induced an approximately 40% increase in the proliferation of A498 cells as assessed by bromodeoxyuridine uptake. This effect was blocked by the ERK inhibitor PD98059, and was dependent on NHE activity

  16. Epstein-Barr virus nuclear antigen 3A promotes cellular proliferation by repression of the cyclin-dependent kinase inhibitor p21WAF1/CIP1.

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    Melissa L Tursiella

    2014-10-01

    Full Text Available Latent infection by Epstein-Barr virus (EBV is highly associated with the endemic form of Burkitt lymphoma (eBL, which typically limits expression of EBV proteins to EBNA-1 (Latency I. Interestingly, a subset of eBLs maintain a variant program of EBV latency - Wp-restricted latency (Wp-R - that includes expression of the EBNA-3 proteins (3A, 3B and 3C, in addition to EBNA-1. In xenograft assays, Wp-R BL cell lines were notably more tumorigenic than their counterparts that maintain Latency I, suggesting that the additional latency-associated proteins expressed in Wp-R influence cell proliferation and/or survival. Here, we evaluated the contribution of EBNA-3A. Consistent with the enhanced tumorigenic potential of Wp-R BLs, knockdown of EBNA-3A expression resulted in abrupt cell-cycle arrest in G0/G1 that was concomitant with conversion of retinoblastoma protein (Rb to its hypophosphorylated state, followed by a loss of Rb protein. Comparable results were seen in EBV-immortalized B lymphoblastoid cell lines (LCLs, consistent with the previous observation that EBNA-3A is essential for sustained growth of these cells. In agreement with the known ability of EBNA-3A and EBNA-3C to cooperatively repress p14(ARF and p16(INK4a expression, knockdown of EBNA-3A in LCLs resulted in rapid elevation of p14(ARF and p16I(NK4a. By contrast, p16(INK4a was not detectably expressed in Wp-R BL and the low-level expression of p14(ARF was unchanged by EBNA-3A knockdown. Amongst other G1/S regulatory proteins, only p21(WAF1/CIP1, a potent inducer of G1 arrest, was upregulated following knockdown of EBNA-3A in Wp-R BL Sal cells and LCLs, coincident with hypophosphorylation and destabilization of Rb and growth arrest. Furthermore, knockdown of p21(WAF1/CIP1 expression in Wp-R BL correlated with an increase in cellular proliferation. This novel function of EBNA-3A is distinct from the functions previously described that are shared with EBNA-3C, and likely contributes to

  17. Tumor suppressor miR-149-5p is associated with cellular migration, proliferation and apoptosis in renal cell carcinoma.

    Science.gov (United States)

    Jin, Lu; Li, Yifan; Liu, Jiaju; Yang, Shangqi; Gui, Yaoting; Mao, Xiangming; Nie, Guohui; Lai, Yongqing

    2016-06-01

    Several studies have recently explored the role of microRNAs (miRNAs, miRs) in the tumorigenesis of various types of cancer. miRNAs have been reported to be involved in numerous cell processes, including cell apoptosis, proliferation and migration, thus suggesting that miRNAs may have an important role in cancer progression. Downregulation of miR-149-5p has been detected in RCC tissues by microarray profiling; however, its expression and function in RCC has yet to be elucidated. In the present study, reverse transcription‑quantitative polymerase chain reaction was performed to detect the expression levels of miR‑149‑5p in RCC tissues and paired normal tissues. In order to determine whether miR-149-5p was able to regulate cell proliferation, apoptosis or migration, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, flow cytometric and wound healing assays were conducted. The results demonstrated that miR‑149‑5p was significantly downregulated in RCC tissues compared with in normal tissues (P<0.05). The restoration of miR-149-5p expression using synthetic mimics suppressed cell proliferation and migration, and promoted cell apoptosis. These results indicated that miR‑149‑5p may act as a tumor suppressor in RCC. The present study is the first, to the best of our knowledge, to identify miR‑149‑5p as a tumor suppressor in RCC. Future studies will be focused on the potential role of miR‑149‑5p as a biomarker for the early detection and prognostic prediction of RCC, and as a therapeutic target in RCC. In addition, further exploration regarding the pathways underlying the effects of miR‑149‑5p in RCC is required. PMID:27121091

  18. In vitro study of possible microbial indicators for drowning: Salinity and types of bacterioplankton proliferating in blood.

    Science.gov (United States)

    Kakizaki, Eiji; Kozawa, Shuji; Matsuda, Hirokazu; Muraoka, Eri; Uchiyama, Taketo; Sakai, Masahiro; Yukawa, Nobuhiro

    2011-01-30

    Numbers and types of bacterioplankton proliferating in blood samples mixed with water of various salinity levels were examined to determine the characteristics of species associated with salinity. Water samples (total n=88) were collected from the midstream of two rivers (freshwater; n=10; salinity rivers, n=28, salinity 2.4-3.3%), and from the coast (areas of marine water; n=10; salinity 3.3-3.5%). Freshwater bacteria were identified in 41 of 42 blood samples mixed with water at ≤1.3% salinity, and the genus Aeromonas, which is universally distributed in freshwater environments, was predominant. Marine bacteria were identified in all of 46 blood samples mixed with water at ≥1.8% salinity, and most comprised the genera Vibrio and Photobacterium that are universally distributed in seawater environments. Aeromonas was undetectable in all blood samples mixed with brackish or sea water at ≥1.8% salinity although they are detectable even in seawater environments. Thus, the present results showed that bacterioplankton capable of proliferating in human blood reflects the salinity of water. PMID:20554407

  19. Over-expression of 60s ribosomal L23a is associated with cellular proliferation in SAG resistant clinical isolates of Leishmania donovani.

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    Sanchita Das

    Full Text Available BACKGROUND: Sodium antimony gluconate (SAG unresponsiveness of Leishmania donovani (Ld had effectively compromised the chemotherapeutic potential of SAG. 60s ribosomal L23a (60sRL23a, identified as one of the over-expressed protein in different resistant strains of L.donovani as observed with differential proteomics studies indicates towards its possible involvement in SAG resistance in L.donovani. In the present study 60sRL23a has been characterized for its probable association with SAG resistance mechanism. METHODOLOGY AND PRINCIPAL FINDINGS: The expression profile of 60s ribosomal L23a (60sRL23a was checked in different SAG resistant as well as sensitive strains of L.donovani clinical isolates by real-time PCR and western blotting and was found to be up-regulated in resistant strains. Ld60sRL23a was cloned, expressed in E.coli system and purified for raising antibody in swiss mice and was observed to have cytosolic localization in L.donovani. 60sRL23a was further over-expressed in sensitive strain of L.donovani to check its sensitivity profile against SAG (Sb V and III and was found to be altered towards the resistant mode. CONCLUSION/SIGNIFICANCE: This study reports for the first time that the over expression of 60sRL23a in SAG sensitive parasite decreases the sensitivity of the parasite towards SAG, miltefosine and paramomycin. Growth curve of the tranfectants further indicated the proliferative potential of 60sRL23a assisting the parasite survival and reaffirming the extra ribosomal role of 60sRL23a. The study thus indicates towards the role of the protein in lowering and redistributing the drug pressure by increased proliferation of parasites and warrants further longitudinal study to understand the underlying mechanism.

  20. Assessment of the proliferative, apoptotic and cellular renovation indices of the human mammary epithelium during the follicular and luteal phases of the menstrual cycle

    International Nuclear Information System (INIS)

    During the menstrual cycle, the mammary gland goes through sequential waves of proliferation and apoptosis. In mammary epithelial cells, hormonal and non-hormonal factors regulate apoptosis. To determine the cyclical effects of gonadal steroids on breast homeostasis, we evaluated the apoptotic index (AI) determined by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) staining in human mammary epithelial cells during the spontaneous menstrual cycle and correlated it with cellular proliferation as determined by the expression of Ki-67 during the same period. Normal breast tissue samples were obtained from 42 randomly selected patients in the proliferative (n = 21) and luteal (n = 21) phases. Menstrual cycle phase characterization was based on the date of the last and subsequent menses, and on progesterone serum levels obtained at the time of biopsy. The proliferation index (PI), defined as the number of Ki-67-positive nuclei per 1,000 epithelial cells, was significantly larger in the luteal phase (30.46) than in the follicular phase (13.45; P = 0.0033). The AI was defined as the number of TUNEL-positive cells per 1,000 epithelial cells. The average AI values in both phases of the menstrual cycle were not statistically significant (P = 0.21). However, the cell renewal index (CRI = PI/AI) was significantly higher in the luteal phase (P = 0.033). A significant cyclical variation of PI, AI and CRI was observed. PI and AI peaks occurred on about the 24th day of the menstrual cycle, whereas the CRI reached higher values on the 28th day. We conclude that proliferative activity is dependent mainly on hormonal fluctuations, whereas apoptotic activity is probably regulated by hormonal and non-hormonal factors

  1. Outcome and human epidermal growth factor receptor (HER) 1–4 status in invasive breast carcinomas with proliferation indices evaluated by bromodeoxyuridine labelling

    International Nuclear Information System (INIS)

    We have shown previously that whereas overexpression of human epidermal growth factor receptor (HER)1, HER2 and HER3 is associated with poor prognosis in breast cancer, HER4 is associated with a good prognosis. Cell proliferation is a key component of aggressive cancers and is driven by growth factors. In this study, bromodeoxyuridine (BrdU)-derived proliferation indices are correlated with clinical outcome and HER1–4 status for further clarification of the differing roles for the HER family at a biological level. Seventy-eight invasive breast cancers had BrdU labelling in vivo to determine the BrdU labelling index (BLI) and the potential tumour doubling time (Tpot). Long-term clinical follow-up was available for these patients. We used immunohistochemistry to establish the HER1–4 status in 55 patients from the BrdU cohort. We demonstrate a significant correlation between high BLI values and breast cancer-specific death (P = 0.0174). Low Tpot times were also significantly correlated with breast cancer-specific death (P = 0.0258). However, BLI did not independently predict survival in Cox's multiple regression analysis when combined with other prognostic factors such as size, grade and nodal status. Tumours found to be positive for HER1, HER2 or HER3 had significantly (P = 0.041) higher labelling indices, with HER1 also showing significantly higher indices when considered independently (P = 0.024). Conversely, HER4 positivity was significantly correlated (P = 0.013) with low BLI values, in line with previous data associating this receptor with good prognosis tumours. These results support the hypothesis that HER1–3 are associated with driving tumour proliferation, whereas HER4 is involved in a non-proliferative or even protective role

  2. Effect of prior dietary exposure to cow’s milk protein on antigen-specific and nonspecific cellular proliferation in mice

    DEFF Research Database (Denmark)

    Pedersen, Susanne Brix; Magyar, O.H.; Barkholt, Vibeke;

    2005-01-01

    -casein peptides was further assessed on cells from mice bred on a cows'-milk-free diet. Regarding the dietary effect, we found that prior oral intake of cows' milk proteins affected cell proliferation induced by culturing with cows' milk proteins in vitro, as spleen cells from mice fed a milk-containing diet...... showed a significantly greater proliferative response than did cells from mice bred on a cows'-milk-free diet. Studies of immune enhancing potentials of beta-casein peptides showed that some peptides stimulate proliferation of immune cells nonspecifically. In conclusion, these findings stress the...... cell donors. Focusing on the immunostimulatory potential of cows' milk proteins and peptides, we studied the impact of prior dietary exposure to cows' milk on proliferation of murine immune cells upon ex vivo stimulation with bovine milk proteins. Nonspecific proliferation induced by beta...

  3. Comparative transcriptome analyses indicate enhanced cellular protection against FMDV in PK15 cells pretreated with IFN-γ.

    Science.gov (United States)

    Fu, Yin; Zhu, Zesen; Chang, Huiyun; Liu, Zaixin; Liu, Jing; Chen, Huiyong

    2016-07-25

    Interferon gamma (IFN-γ) can induce a host antiviral response to foot and mouth disease virus (FMDV) in vivo and in vitro. To elucidate the mechanism of IFN-γ anti FMDV infection in host cells, high-throughput RNA sequencing was analyzed for systemic changes in gene expression profiles in PK15 cells infected by FMDV with or without IFN-γ pretreatment. More than 25 million reads, covering 1.2-1.5 Gb, were analyzed from each experiment panel. FMDV challenge altered the transcription of genes involved in positively and negatively regulating cell death or apoptosis; however, the expected immune suppression response was not obvious. IFN-γ pretreatment combined with FMDV infection normalized the increase in apoptosis. Furthermore, the transcription factors required for IFN-γ functioning, STAT1 and IRF1 were up-regulated by IFN-γ pretreatment and stimulated downstream IFN-stimulated genes (ISGs). These induced ISGs are mainly responsible for antigen processing, antigen presentation or antiviral defense. Interestingly, a synergistic effect on some ISGs, including OAS1, OAS2, MX1, MX2, RIG-I and IFIT1, was observed in the combined treatment compared to the IFN-γ treatment alone. The suggested effects identified by RNA sequencing were consistent with cellular morphology changes and confirmed by related protein markers. This is the first report exploring transcriptome alterations introduced by FMDV infection with or without IFN-γ pretreatment. The identified key host genes that control cell survival in vitro broaden our comprehensive understanding of how IFN-γ inhibits FMDV infection and may shed light on developing improved FMD control approaches. PMID:27018244

  4. Nerve Regeneration Potential of Protocatechuic Acid in RSC96 Schwann Cells by Induction of Cellular Proliferation and Migration through IGF-IR-PI3K-Akt Signaling.

    Science.gov (United States)

    Ju, Da-Tong; Liao, Hung-En; Shibu, Marthandam Asokan; Ho, Tsung-Jung; Padma, Viswanadha Vijaya; Tsai, Fuu-Jen; Chung, Li-Chin; Day, Cecilia Hsuan; Lin, Chien-Chung; Huang, Chih-Yang

    2015-12-31

    Peripheral nerve injuries, caused by accidental trauma, acute compression or surgery, often result in temporary or life-long neuronal dysfunctions and inflict great economic or social burdens on the patients. Nerve cell proliferation is an essential process to restore injured nerves of adults. Schwann cells play a crucial role in endogenous repair of peripheral nerves due to their ability to proliferate, migrate and provide trophic support to axons via expression of various neurotrophic factors, such as the nerve growth factor (NGF), especially after nerve injury. Protocatechuic acid (PCA) is a dihydroxybenzoic acid, a type of phenolic acid, isolated from the kernels of Alpinia oxyphylla Miq (AOF), a traditional Chinese herbal medicine the fruits of which are widely used as a tonic, aphrodisiac, anti-salivation and anti-diarrheatic. This study investigated the molecular mechanisms by which PCA induces Schwann cell proliferation by activating IGF-IR-PI3K-Akt pathway. Treatment with PCA induces phosphorylation of the insulin-like growth factor-I (IGF-I)-mediated phosphatidylinositol 3 kinase/serine - threonine kinase (PI3K/Akt) pathway, and activates expression of cell nuclear antigen (PCNA) in a dose-dependent manner. Cell cycle analysis after 18 h of treatment showed that proliferation of the RSC96 cells was enhanced by PCA treatment. The PCA induced proliferation was accompanied by modulation in the expressions of cell cycle proteins cyclin D1, cyclin E and cyclin A. Knockdown of PI3K using small interfering RNA (siRNA) and inhibition of IGF-IR receptor resulted in the reduction in cell survival proteins. The results collectively showed that PCA treatment promoted cell proliferation and cell survival via IGF-I signaling. PMID:26717920

  5. Influence of cellular ER alpha/ER beta ratio on the ER alpha-agonist induced proliferation of human T47D breast cancer cells

    NARCIS (Netherlands)

    Sotoca Covaleda, A.M.; Berg, van den H.; Vervoort, J.J.M.; Saag, van der P.; Strom, A.; Gustafsson, J.A.; Rietjens, I.M.C.M.; Murk, A.J.

    2008-01-01

    Breast cancer cells show overexpression of estrogen receptor (ER) relative to ERß compared to normal breast tissues. This observation has lead to the hypothesis that ERß may modulate the proliferative effect of ER. This study investigated how variable cellular expression ratios of the ER and ERß mod

  6. Binding of sFRP-3 to EGF in the extra-cellular space affects proliferation, differentiation and morphogenetic events regulated by the two molecules

    OpenAIRE

    R. Scardigli; Cargiolo, C; Tosoni, D.; Borello, U; Sampaolesi, Maurilio; Sciorati, C.; Cannata, S.; E. Clementi; Brunelli, S.; Cossu, G.

    2008-01-01

    Background sFRP-3 is a soluble antagonist of Wnts, widely expressed in developing embryos. The Wnt gene family comprises cysteine-rich secreted ligands that regulate cell proliferation, differentiation, organogenesis and oncogenesis of different organisms ranging from worms to mammals. In the canonical signal transduction pathway Wnt proteins bind to the extracellular domain of Frizzled receptors and consequently recruit Dishevelled (Dsh) to the cell membrane. In addition to Wnt membrane rece...

  7. Hepatitis C virus E2 protein promotes human hepatoma cell proliferation through the MAPK/ERK signaling pathway via cellular receptors

    International Nuclear Information System (INIS)

    Dysregulation of mitogen-activated protein kinase (MAPK) signaling pathways by various viruses has been shown to be responsible for viral pathogenicity. The molecular mechanism by which hepatitis C virus (HCV) infection caused human liver diseases has been investigated on the basis of abnormal intracellular signal events. Current data are very limited involved in transmembrane signal transduction triggered by HCV E2 protein. Here we explored regulation of the MAPK/extracellular signal-regulated kinase (MAPK/ERK) signaling pathway by E2 expressed in Chinese hamster oval cells. In human hepatoma Huh-7 cells, E2 specifically activated the MAPK/ERK pathway including downstream transcription factor ATF-2 and greatly promoted cell proliferation. CD81 and low density lipoprotein receptor (LDLR) on the cell surface mediated binding of E2 to Huh-7 cells. The MAPK/ERK activation and cell proliferation driven by E2 were suppressed by blockage of CD81 as well as LDLR. Furthermore, pretreatment with an upstream kinase MEK1/2 inhibitor U0126 also impaired the MAPK/ERK activation and cell proliferation induced by E2. Our results suggest that the MAPK/ERK signaling pathway triggered by HCV E2 via its receptors maintains survival and growth of target cells

  8. Binding of sFRP-3 to EGF in the extra-cellular space affects proliferation, differentiation and morphogenetic events regulated by the two molecules.

    Directory of Open Access Journals (Sweden)

    Raffaella Scardigli

    Full Text Available BACKGROUND: sFRP-3 is a soluble antagonist of Wnts, widely expressed in developing embryos. The Wnt gene family comprises cysteine-rich secreted ligands that regulate cell proliferation, differentiation, organogenesis and oncogenesis of different organisms ranging from worms to mammals. In the canonical signal transduction pathway Wnt proteins bind to the extracellular domain of Frizzled receptors and consequently recruit Dishevelled (Dsh to the cell membrane. In addition to Wnt membrane receptors belonging to the Frizzled family, several other molecules have been described which share homology in the CRD domain and lack the putative trans-membrane domain, such as sFRP molecules (soluble Frizzled Related Protein. Among them, sFRP-3 was originally isolated from bovine articular cartilage and also as a component of the Spemann organizer. sFRP-3 blocks Wnt-8 induced axis duplication in Xenopus embryos and binds to the surface of cells expressing a membrane-anchored form of Wnt-1. Injection of sFRP-3 mRNA blocks expression of XMyoD mRNA and leads to embryos with enlarged heads and shortened trunks. METHODOLOGY/PRINCIPAL FINDINGS: Here we report that sFRP-3 specifically blocks EGF-induced fibroblast proliferation and foci formation. Over-expression of sFRP-3 reverts EGF-mediated inhibition of hair follicle development in the mouse ectoderm while its ablation in Xenopus maintains EGF-mediated inhibition of ectoderm differentiation. Conversely, over-expression of EGF reverts the inhibition of somitic myogenesis and axis truncation in Xenopus and mouse embryos caused by sFRP-3. In vitro experiments demonstrated a direct binding of EGF to sFRP-3 both on heparin and on the surface of CHO cells where the molecule had been membrane anchored. CONCLUSIONS/SIGNIFICANCE: sFRP-3 and EGF reciprocally inhibit their effects on cell proliferation, differentiation and morphogenesis and indeed are expressed in contiguous domains of the embryo, suggesting that in

  9. Inhibition of Macrophage CD36 Expression and Cellular Oxidized Low Density Lipoprotein (oxLDL) Accumulation by Tamoxifen: A PEROXISOME PROLIFERATOR-ACTIVATED RECEPTOR (PPAR)γ-DEPENDENT MECHANISM.

    Science.gov (United States)

    Yu, Miao; Jiang, Meixiu; Chen, Yuanli; Zhang, Shuang; Zhang, Wenwen; Yang, Xiaoxiao; Li, Xiaoju; Li, Yan; Duan, Shengzhong; Han, Jihong; Duan, Yajun

    2016-08-12

    Macrophage CD36 binds and internalizes oxidized low density lipoprotein (oxLDL) to facilitate foam cell formation. CD36 expression is activated by peroxisome proliferator-activated receptor γ (PPARγ). Tamoxifen, an anti-breast cancer medicine, has demonstrated pleiotropic functions including cardioprotection with unfully elucidated mechanisms. In this study, we determined that treatment of ApoE-deficient mice with tamoxifen reduced atherosclerosis, which was associated with decreased CD36 and PPARγ expression in lesion areas. At the cellular level, we observed that tamoxifen inhibited CD36 protein expression in human THP-1 monocytes, THP-1/PMA macrophages, and human blood monocyte-derived macrophages. Associated with decreased CD36 protein expression, tamoxifen reduced cellular oxLDL accumulation in a CD36-dependent manner. At the transcriptional level, tamoxifen decreased CD36 mRNA expression, promoter activity, and the binding of the PPARγ response element in CD36 promoter to PPARγ protein. Tamoxifen blocked ligand-induced PPARγ nuclear translocation and CD36 expression, but it increased PPARγ phosphorylation, which was due to that tamoxifen-activated ERK1/2. Furthermore, deficiency of PPARγ expression in macrophages abolished the inhibitory effect of tamoxifen on CD36 expression or cellular oxLDL accumulation both in vitro and in vivo Taken together, our study demonstrates that tamoxifen inhibits CD36 expression and cellular oxLDL accumulation by inactivating the PPARγ signaling pathway, and the inhibition of macrophage CD36 expression can be attributed to the anti-atherogenic properties of tamoxifen. PMID:27358406

  10. Odd-skipped related 2 regulates genes related to proliferation and development

    Energy Technology Data Exchange (ETDEWEB)

    Kawai, Shinji, E-mail: skawai@dent.osaka-u.ac.jp [Department of Oral Frontier Biology, Osaka University Graduate School of Dentistry, Suita-Osaka 565-0871 (Japan); Abiko, Yoshimitsu [Department of Biochemistry, Nihon University School of Dentistry at Matsudo, Matsudo-Chiba 271-8587 (Japan); Amano, Atsuo [Department of Oral Frontier Biology, Osaka University Graduate School of Dentistry, Suita-Osaka 565-0871 (Japan)

    2010-07-23

    Cell proliferation is a biological process in which chromosomes replicate in one cell and equally divide into two daughter cells. Our previous findings suggested that Odd-skipped related 2 (Osr2) plays an important role in cellular quiescence and proliferation under epigenetic regulation. However, the mechanism used by Osr2 to establish and maintain proliferation is unknown. To examine the functional role of Osr2 in cell proliferation, we analyzed its downstream target genes using microarray analysis following adenovirus-induced overexpression of Osr2 as well as knockdown with Osr2 siRNA, which showed that Osr2 regulates a multitude of genes involved in proliferation and the cell cycle, as well as development. Additional proliferation assays also indicated that Osr2 likely functions to elicit cell proliferation. Together, these results suggest that Osr2 plays important roles in proliferation and development.

  11. Odd-skipped related 2 regulates genes related to proliferation and development

    International Nuclear Information System (INIS)

    Cell proliferation is a biological process in which chromosomes replicate in one cell and equally divide into two daughter cells. Our previous findings suggested that Odd-skipped related 2 (Osr2) plays an important role in cellular quiescence and proliferation under epigenetic regulation. However, the mechanism used by Osr2 to establish and maintain proliferation is unknown. To examine the functional role of Osr2 in cell proliferation, we analyzed its downstream target genes using microarray analysis following adenovirus-induced overexpression of Osr2 as well as knockdown with Osr2 siRNA, which showed that Osr2 regulates a multitude of genes involved in proliferation and the cell cycle, as well as development. Additional proliferation assays also indicated that Osr2 likely functions to elicit cell proliferation. Together, these results suggest that Osr2 plays important roles in proliferation and development.

  12. E2F1-mediated upregulation of p19INK4d determines its periodic expression during cell cycle and regulates cellular proliferation.

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    Abel L Carcagno

    Full Text Available BACKGROUND: A central aspect of development and disease is the control of cell proliferation through regulation of the mitotic cycle. Cell cycle progression and directionality requires an appropriate balance of positive and negative regulators whose expression must fluctuate in a coordinated manner. p19INK4d, a member of the INK4 family of CDK inhibitors, has a unique feature that distinguishes it from the remaining INK4 and makes it a likely candidate for contributing to the directionality of the cell cycle. p19INK4d mRNA and protein levels accumulate periodically during the cell cycle under normal conditions, a feature reminiscent of cyclins. METHODOLOGY/PRINCIPAL FINDINGS: In this paper, we demonstrate that p19INK4d is transcriptionally regulated by E2F1 through two response elements present in the p19INK4d promoter. Ablation of this regulation reduced p19 levels and restricted its expression during the cell cycle, reflecting the contribution of a transcriptional effect of E2F1 on p19 periodicity. The induction of p19INK4d is delayed during the cell cycle compared to that of cyclin E, temporally separating the induction of these proliferative and antiproliferative target genes. Specific inhibition of the E2F1-p19INK4d pathway using triplex-forming oligonucleotides that block E2F1 binding on p19 promoter, stimulated cell proliferation and increased the fraction of cells in S phase. CONCLUSIONS/SIGNIFICANCE: The results described here support a model of normal cell cycle progression in which, following phosphorylation of pRb, free E2F induces cyclin E, among other target genes. Once cyclinE/CDK2 takes over as the cell cycle driving kinase activity, the induction of p19 mediated by E2F1 leads to inhibition of the CDK4,6-containing complexes, bringing the G1 phase to an end. This regulatory mechanism constitutes a new negative feedback loop that terminates the G1 phase proliferative signal, contributing to the proper coordination of the cell

  13. miRNA array analysis determines miR-205 is overexpressed in head and neck squamous cell carcinoma and enhances cellular proliferation

    Directory of Open Access Journals (Sweden)

    Howard JD

    2013-08-01

    Full Text Available MicroRNAs (miRNAs play a critical role in cell cycle and pro-survival signal regulation. Consequently, their deregulation can enhance tumorigenesis and cancer progression. In the current investigation, we determined whether cancer- or human papillomavirus (HPV-specific miRNA deregulation could further elucidate signal transduction events unique to head and neck squamous cell carcinoma (HNSCC. Twenty-nine newly diagnosed HNSCC tumors (HPV-positive: 14, HPV-negative: 15 and four normal mucosa samples were analyzed for global miRNA expression. Differential miRNA expression analysis concluded HNSCC is characterized by a general upregulation of miRNAs compared to normal mucosa. Additionally, miR-449a and miR-129-3p were statistically significant miRNAs differentially expressed between HPV-positive and HPV-negative HNSCC. The upregulation of miR-449a was also validated within an independent dataset obtained from TCGA containing 279 HNSCCs and 39 normal adjacent mucosa samples. To gain a better understanding of miRNA-mediated cell cycle deregulation in HNSCC, we functionally evaluated miR-205, a transcript upregulated in our cancer-specific analysis and a putative regulator of E2F1. Modulation of miR-205 with a miRNA mimic and inhibitor revealed miR-205 is capable of regulating E2F1 expression in HNSCC and overexpression of this transcript enhances proliferation. This study demonstrates miRNA expression is highly deregulated in HNSCC and functional evaluations of these miRNAs may reveal novel HPV context dependent mechanisms in this disease.

  14. Uterine leiomyomas/fibroids are the most common pelvic tumors of the female genital tract. Transforming growth factor beta (TGF β family members are multi-functional cytokines that play a key role in cellular growth, proliferation and differentiation. The aim of this study was to investigate whether TGF β1 - 509 C/T polymorphism could be used as a susceptibility marker in Uterine fibroids pathogenesis. ARMS PCR was carried out for controls and patients (n=103 to identify the specific genotypes. Genotypes and allelic frequencies in both groups were compared. Proportions of C homozygote, heterozygote and T homozygote for TGF β1gene polymorphisms were 37.9%, 44.7%, 17.5% in the control individuals and 37%, 51.5%, 11.7% in the uterine fibroid patients. There was no significant difference between the controls and the patients thus indicating the tumor suppressor effect of TGF β1 in the early stages of tumor pathogenesis. The study was found to be in association with the earlier reported data wherein TGF β1 acts as tumor suppressor in the early stages and as a tumor promoter in the later stages of tumor pathogenesis

    Directory of Open Access Journals (Sweden)

    M.Veronica

    2013-06-01

    Full Text Available Uterine leiomyomas/fibroids are the most common pelvic tumors of the female genital tract. Transforming growth factor beta (TGF β family members are multi-functional cytokines that play a key role in cellular growth, proliferation and differentiation. The aim of this study was to investigate whether TGF β1 - 509 C/T polymorphism could be used as a susceptibility marker in Uterine fibroids pathogenesis. ARMS PCR was carried out for controls and patients (n=103 to identify the specific genotypes. Genotypes and allelic frequencies in both groups were compared. Proportions of C homozygote, heterozygote and T homozygote for TGF β1gene polymorphisms were 37.9%, 44.7%, 17.5% in the control individuals and 37%, 51.5%, 11.7% in the uterine fibroid patients. There was no significant difference between the controls and the patients thus indicating the tumor suppressor effect of TGF β1 in the early stages of tumor pathogenesis. The study was found to be in association with the earlier reported data wherein TGF β1 acts as tumor suppressor in the early stages and as a tumor promoter in the later stages of tumor pathogenesis

  15. Differential regulation of cell proliferation in neurogenic zones in mice lacking cystine transport by xCT

    International Nuclear Information System (INIS)

    The cystine/glutamate exchanger (xCT) supplies intracellular cyst(e)ine for the production of glutathione, a major cellular anti-oxidant. xCT is enriched in brain regions associated with neurogenesis. Previous studies have shown that the malfunction of this protein greatly attenuates cell proliferation in vitro and is associated with brain atrophy in vivo. Using mice that are homozygous for a function-blocking deletion in xCT (Sut mice), we examined in vivo the role of xCT in cell proliferation in neurogenic regions of the subventricular zone (SVZ) and denate gyrus (DG) in the adult brain. Our results indicate that a high level of cellular proliferation in the adult brain persists even in the absence of functional xCT. Furthermore, in both young adult and middle-aged mice (3 and 11 months old), rates of SVZ cell proliferation were comparable between Sut and wild-type controls, although there was trend towards reduced proliferation in Sut mice (12% and 9% reduction, respectively). To our surprise, rates of cell proliferation in the DG were elevated in both 3- and 11-month-old Sut mice relative to controls (22% and 28% increase, respectively). These results demonstrate that xCT expression plays a role in regulating cellular proliferation in the DG, but not the SVZ of adult mice. Furthermore, unlike previous in vitro studies, our in vivo observations clearly indicate that xCT is not essential for ongoing cellular proliferation

  16. Can we predict nuclear proliferation

    International Nuclear Information System (INIS)

    The author aims at improving nuclear proliferation prediction capacities, i.e. the capacities to identify countries susceptible to acquire nuclear weapons, to interpret sensitive activities, and to assess nuclear program modalities. He first proposes a retrospective assessment of counter-proliferation actions since 1945. Then, based on academic studies, he analyzes what causes and motivates proliferation, with notably the possibility of existence of a chain phenomenon (mechanisms driving from one program to another). He makes recommendations for a global approach to proliferation prediction, and proposes proliferation indices and indicators

  17. Predicting Cellular Growth from Gene Expression Signatures

    OpenAIRE

    Dunham, Maitreya J.; Troyanskaya, Olga G.; Airoldi, Edoardo; Broach, James R.; Caudy, Amy A.; Gresham, David; Botstein, David; Huttenhower, Curtis; Lu, Charles

    2009-01-01

    Maintaining balanced growth in a changing environment is a fundamental systems-level challenge for cellular physiology, particularly in microorganisms. While the complete set of regulatory and functional pathways supporting growth and cellular proliferation are not yet known, portions of them are well understood. In particular, cellular proliferation is governed by mechanisms that are highly conserved from unicellular to multicellular organisms, and the disruption of these processes in metazo...

  18. Cellular and molecular biomarkers indicate precocious in vitro senescence in fibroblasts from SAMP6 mice. Evidence supporting a murine model of premature senescence and osteopenia.

    Science.gov (United States)

    Lecka-Czernik, B; Moerman, E J; Shmookler Reis, R J; Lipschitz, D A

    1997-11-01

    A variety of short-lived mouse strains (SAMP strains) and control strains of less abbreviated life span (SAMR strains) have been proposed as murine models of accelerated senescence. Each SAMP strain, in addition to displaying "progeroid" traits of accelerated aging, exhibits a singular age-related pathology. The application of this animal model to the study of normal aging processes has been and remains controversial. Therefore, we have undertaken a study of dermal fibroblasts derived from the short-lived SAMP6 strain, which shows early-onset and progressive osteopenia. We have investigated cellular and molecular characteristics that are associated with in vitro aging of normal human fibroblasts, and which are exacerbated in fibroblasts from patients with Werner syndrome, a human model of premature senescence. We found that SAMP6 dermal fibroblasts, relative to SAMR1 and C57BL/6 controls, exhibit characteristics of premature or accelerated cellular senescence with regard to in vitro life span, initial growth rate, and patterns of gene expression. PMID:9402934

  19. Regulation of proliferation of embryonic heart mesenchyme: Role of transforming growth factor-beta 1 and the interstitial matrix

    International Nuclear Information System (INIS)

    Proliferation of atrioventricular cushion mesenchyme of the embryonic avian heart maintained in three-dimensional aggregate culture is stimulated by interaction with the interstitial matrix. Chicken serum or transforming growth factor-beta 1, which stimulates proliferation, induces matrix deposition in regions of the aggregate showing high labeling indices with tritiated thymidine. Dispersed heart mesenchyme interstitial matrix introduced into serum-free culture is incorporated into the aggregate and stimulates cellular proliferation similar to serum or transforming growth factor-beta 1. Proliferation is reversibly inhibited by the peptide Gly-Arg-Gly-Asp-Ser-Pro. It is suggested that transforming growth factor-beta 1 stimulates the production of interstitial matrix and that a sufficient stimulus for proliferation in this system is the presence of the matrix, which acts as the adhesive support for cellular anchorage

  20. Cellular Functions of Transient Receptor Potential channels

    OpenAIRE

    Dadon, Daniela; Minke, Baruch

    2010-01-01

    Transient Receptor Potential channels are polymodal cellular sensors involved in a wide variety of cellular processes, mainly by increasing cellular Ca2+. In this review we focus on the roles of these channels in: i) cell death ii) proliferation and differentiation and iii) synaptic vesicle release.

  1. Cellular Adhesion Tripeptide RGD Inhibits Growth of Human Ileocecal Adenocarcinoma Cells HCT-8 and Induces Apoptosis

    Institute of Scientific and Technical Information of China (English)

    WANG Hua; ZENG Hong-bin; YANG Shao-juan; GAO Shen; HUANG Yi-bing; HOU Rui-zhen; ZHAO Mi-feng; XU Li; ZHANG Xue-zhong

    2007-01-01

    The tripeptide, Arg-Gly-Asp(RGD) motif is an integrin-recognition site found in adhesive proteins present in extracellular matrices(ECM) and in the blood. HCT-8 cells were treated with cellular adhesion tripeptide RGD at various concentrations. MTT assay was performed to examine the growth and proliferation of HCT-8 cells after treatment with RGD for 48 h. Haematoxylin and Eosin(HE) staining and electromicroscope were used to observe the morphology of apoptotic cells. Survivin and flow cytometry were also used to analyze the HCT-8 apoptosis. Cellular adhesion tripeptide RGD significantly inhibits the growth and proliferation of HCT-8 cells in a dose-dependent manner and induces apoptosis of HCT-8. These results indicate that cellular adhesion tripeptide RGD inhibits the growth and proliferation of tumor HCT-8 cell, probably by the aid of inducing apoptosis of HCT-8 cell.

  2. Evaluación de la inmunidad celular en caninos: prueba de proliferación de linfocitos in vitro Evaluation of cellular immunity in dogs: in vitro lymphocyte proliferation test

    Directory of Open Access Journals (Sweden)

    L. G Ramayo

    2005-12-01

    Full Text Available La prueba de proliferación de linfocitos inducida por mitógenos in vitro se utiliza para evaluar la inmunidad celular. En el presente trabajo, se comparan los resultados obtenidos con el método tradicional, que utiliza linfocitos purificados para el cultivo y la captación de timidina tritiada como método de medición de la proliferación (LP- ³H, con otras dos metodologías: el uso de sangre entera con revelado por captación de timidina tritiada (SE-³H y el uso de linfocitos purificados con revelado por ensayo colorimétrico con MTT (LP-MTT. Se trabajó sobre muestras de 12 caninos clínicamente sanos que fueron procesadas por las tres metodologías. Se utilizó Concanavalina A como mitógeno y el Indice de Estimulación (IE como expresión de los resultados. El método de SE-³H arrojó valores de IE significativamente mayores que la técnica clásica, por lo que resultaría útil para evaluar la proliferación linfocitaria en caninos en nuestras condiciones de trabajo. El método de LP-MTT mostró valores de IE significativamente menores, por lo que se requieren más estudios para evaluar su posible uso en la medición de la funcionalidad linfocitaria. Sobre la base de los resultados obtenidos se estableció un rango normal de valores de IE para cada método.In vitro mitogen induced lymphocyte proliferation test is widely used for evaluation of cellmediated immunity. In the present work, we compare the results of the traditional method, which uses gradient isolated lymphocytes as the source of cells for the culture and tritiated thymidine incorporation to measure proliferative response (LP- ³H, with other two methods: culture of whole blood and proliferation measure with ³H- thymidine (SE-³H, and culture of isolated lymphocytes and proliferation evaluation with a colorimetric assay using MTT (LP-MTT. Blood samples of twelve adult, healthy dogs were processed by the three mentioned methods, using Concanavalin- A as mitogen and the

  3. Proliferation risks

    International Nuclear Information System (INIS)

    The report gives an overview of different aspects related to safeguards of fissile materials. Existing treaties including the Non-Proliferation Treaty, and the Tlatelolco and the Rarotonga Treaties are discussed. An overview of safeguards systems for the control of fissile materials as well as the role of various authorities is given. An overall overview of proliferation risks, the physical protection of fissile materials and the trade in fissile materials is given. Finally, the status in problem countries and de facto nuclear weapon states is discussed

  4. Indicators of inflammation and cellular damage in chronic asymptomatic or oligosymptomatic alcoholics: correlation with alteration of bilirubin and hepatic and pancreatic enzymes

    Directory of Open Access Journals (Sweden)

    Borini Paulo

    1999-01-01

    Full Text Available Biochemical and hematimetric indicators of inflammation and cell damage were correlated with bilirubin and hepatic and pancreatic enzymes in 30 chronic male alcoholics admitted into psychiatric hospital for detoxification and treatment of alcoholism. Aspartate aminotransferase, alanine aminotransferase, gamma-glutamyltransferase, alkaline phosphatase, and total bilirubin were altered, respectively, in 90%, 63%, 87%, 23% and 23% of the cases. None of the indicators of inflammation (lactic dehydrogenase, altered in 16% of the cases; alpha-1 globulin, 24%; alpha-2 globulin, 88%; leucocyte counts, 28% was correlated with alterations of bilirubin or liver enzymes. Lactic dehydrogenase was poorly sensitive for detection of hepatocytic or muscular damage. Alterations of alpha-globulins seemed to have been due more to alcohol metabolism-induced increase of lipoproteins than to inflammation. Among indicators of cell damage, serum iron, increased in 40% of the cases, seemed to be related to liver damage while creatine phosphokinase, increased in 84% of the cases, related to muscle damage. Hyperamylasemia was found in 20% of the cases and significantly correlated with levels of bilirubin, alkaline phosphatase and gamma-glutamyltransferase. It was indicated that injuries of liver, pancreas, salivary glands, and muscle occurred in asymptomatic or oligosymptomatic chronic alcoholics.

  5. Handling Proliferation

    Directory of Open Access Journals (Sweden)

    Pierre Laszlo

    2001-10-01

    Full Text Available The ethics of the chemist identify with those of the citizen, in principle. The observed perversions, such as proliferation of chemicals, stem from the values of a chemical community closed upon itself, and from the attendant identification of a mere know-how with a science. The epistemic degradation produces moral indifference.

  6. Cellular automata

    CERN Document Server

    Codd, E F

    1968-01-01

    Cellular Automata presents the fundamental principles of homogeneous cellular systems. This book discusses the possibility of biochemical computers with self-reproducing capability.Organized into eight chapters, this book begins with an overview of some theorems dealing with conditions under which universal computation and construction can be exhibited in cellular spaces. This text then presents a design for a machine embedded in a cellular space or a machine that can compute all computable functions and construct a replica of itself in any accessible and sufficiently large region of t

  7. High-to-low CO2 acclimation reveals plasticity of the photorespiratory pathway and indicates regulatory links to cellular metabolism of Arabidopsis.

    Directory of Open Access Journals (Sweden)

    Stefan Timm

    Full Text Available BACKGROUND: Photorespiratory carbon metabolism was long considered as an essentially closed and nonregulated pathway with little interaction to other metabolic routes except nitrogen metabolism and respiration. Most mutants of this pathway cannot survive in ambient air and require CO(2-enriched air for normal growth. Several studies indicate that this CO(2 requirement is very different for individual mutants, suggesting a higher plasticity and more interaction of photorespiratory metabolism as generally thought. To understand this better, we examined a variety of high- and low-level parameters at 1% CO(2 and their alteration during acclimation of wild-type plants and selected photorespiratory mutants to ambient air. METHODOLOGY AND PRINCIPAL FINDINGS: The wild type and four photorespiratory mutants of Arabidopsis thaliana (Arabidopsis were grown to a defined stadium at 1% CO(2 and then transferred to normal air (0.038% CO(2. All other conditions remained unchanged. This approach allowed unbiased side-by-side monitoring of acclimation processes on several levels. For all lines, diel (24 h leaf growth, photosynthetic gas exchange, and PSII fluorescence were monitored. Metabolite profiling was performed for the wild type and two mutants. During acclimation, considerable variation between the individual genotypes was detected in many of the examined parameters, which correlated with the position of the impaired reaction in the photorespiratory pathway. CONCLUSIONS: Photorespiratory carbon metabolism does not operate as a fully closed pathway. Acclimation from high to low CO(2 was typically steady and consistent for a number of features over several days, but we also found unexpected short-term events, such as an intermittent very massive rise of glycine levels after transition of one particular mutant to ambient air. We conclude that photorespiration is possibly exposed to redox regulation beyond known substrate-level effects. Additionally, our data

  8. Cell proliferation inhibition in reduced gravity

    Science.gov (United States)

    Moos, P. J.; Fattaey, H. K.; Johnson, T. C.; Spooner, B. S. (Principal Investigator)

    1994-01-01

    Extended durations of spaceflight have been shown to be deleterious on an organismic level; however, mechanisms underlying cellular sensitivity to the gravitational environment remain to be elucidated. The majority of the gravitational studies to date indicates that cell regulatory pathways may be influenced by their gravitational environment. Still, few cell biology experiments have been performed in space flight and even fewer experiments have been repeated on subsequent flights. With flight opportunities on STS-50, 54, and 57, Sf9 cells were flown in the BioServe Fluids Processing Apparatus and cell proliferation was measured with and without exposure to a cell regulatory sialoglycopeptide (CeReS) inhibitor. Results from these flights indicate that the Sf9 cells grew comparable to ground controls, that the CeReS inhibitor bound to its specific receptor, and that its signal transduction cascade was not gravity sensitive.

  9. The MRC-5 human embryonal lung fibroblast two-dimensional gel cellular protein database: quantitative identification of polypeptides whose relative abundance differs between quiescent, proliferating and SV40 transformed cells

    DEFF Research Database (Denmark)

    Celis, J E; Dejgaard, K; Madsen, Peder;

    1990-01-01

    proteins quantitated so far, the levels of 138 were up- or down-regulated (51 and 87, respectively) by two times or more in the transformed cells as compared to their normal proliferating counterparts, while only 14 behaved similarly in quiescent cells. Seven MRC-5 SV40 proteins, including plastin and two...

  10. RNase-L Control of Cellular mRNAs: Roles in Biologic Functions and Mechanisms of Substrate Targeting

    OpenAIRE

    Brennan-Laun, Sarah E.; Ezelle, Heather J.; Li, Xiao-Ling; Hassel, Bret A.

    2014-01-01

    RNase-L is a mediator of type 1 interferon-induced antiviral activity that has diverse and critical cellular roles, including the regulation of cell proliferation, differentiation, senescence and apoptosis, tumorigenesis, and the control of the innate immune response. Although RNase-L was originally shown to mediate the endonucleolytic cleavage of both viral and ribosomal RNAs in response to infection, more recent evidence indicates that RNase-L also functions in the regulation of cellular mR...

  11. Gemcitabine resistance in breast cancer cells regulated by PI3K/AKT-mediated cellular proliferation exerts negative feedback via the MEK/MAPK and mTOR pathways

    Directory of Open Access Journals (Sweden)

    Yang XL

    2014-06-01

    Full Text Available Xiao Li Yang, Feng Juan Lin, Ya Jie Guo, Zhi Min Shao, Zhou Luo Ou Key Laboratory of Breast Cancer in Shanghai, Breast Cancer Institute, Cancer Hospital, Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, People's Republic of China Abstract: Chemoresistance is a major cause of cancer treatment failure and leads to a reduction in the survival rate of cancer patients. Phosphatidylinositol 3-kinase/protein kinase B/mammalian target of rapamycin (PI3K/AKT/mTOR and mitogen-activated protein kinase (MAPK pathways are aberrantly activated in many malignant tumors, including breast cancer, which may indicate an association with breast cancer chemoresistance. In this study, we generated a chemoresistant human breast cancer cell line, MDA-MB-231/gemcitabine (simplified hereafter as “231/Gem”, from MDA-MB-231 human breast cancer cells. Flow cytometry studies revealed that with the same treatment concentration of gemcitabine, 231/Gem cells displayed more robust resistance to gemcitabine, which was reflected by fewer apoptotic cells and enhanced percentage of S-phase cells. Through the use of inverted microscopy, Cell Counting Kit-8, and Transwell assays, we found that compared with parental 231 cells, 231/Gem cells displayed more morphologic projections, enhanced cell proliferative ability, and improved cell migration and invasion. Mechanistic studies revealed that the PI3K/AKT/mTOR and mitogen-activated protein kinase kinase (MEK/MAPK signaling pathways were activated through elevated expression of phosphorylated (p-extracellular signal-regulated kinase (ERK, p-AKT, mTOR, p-mTOR, p-P70S6K, and reduced expression of p-P38 and LC3-II (the marker of autophagy in 231/Gem in comparison to control cells. However, there was no change in the expression of Cyclin D1 and p-adenosine monophosphate-activated protein kinase (AMPK. In culture, inhibitors of PI3K/AKT and mTOR, but not of MEK/MAPK, could reverse the enhanced proliferative

  12. Alteration of cellular and subcellular electrophysiological parameters in mammalian cells by high- and low-LET irradiation at low dose-levels. Part of a coordinated programme on cell membrane probes as biological indicators in radiation accidents

    International Nuclear Information System (INIS)

    The transmembrane resting potential (MRP) was chosen as a highly sensitive indicator for cellular reactions. The MRP was studied for its suitability as biological indicator of the level of accidental radiation exposure. The development of methodology and installation of a low-cost test chamber, and dose-response studies of MRP-changes of human cells after irradiation with low- and high-LET radiation were considered. Cultured human embryonic lung fibroblasts and human lung biopsy samples were used, with a Co-60 source for low-LET irradiation at dose rates of 2 rad and 20 rad/min, respectively. For high-LET irradiation an Am-241 source was used. The onset of radiation induced effects on cell membranes was prompt but of short duration. In general, full recovery followed within hours of irradiation, at least under the particular experimental conditions. MRP changes in irradiated cells proved a highly sensitive parameter for assessing radiation effects on cell membranes. It appears premature to draw conclusions on the suitability of the method as a biological indicator of radiation damage from accidental exposure, in view of the short duration and prompt reversibility of the effects, and an incomplete understanding of the radiation-induced reactions involved at different LET's and at different doses and dose-rates

  13. Cellular Automata

    OpenAIRE

    Bagnoli, Franco

    1998-01-01

    An introduction to cellular automata (both deterministic and probabilistic) with examples. Definition of deterministic automata, dynamical properties, damage spreading and Lyapunov exponents; probabilistic automata and Markov processes, nonequilibrium phase transitions, directed percolation, diffusion; simulation techniques, mean field. Investigation themes: life, epidemics, forest fires, percolation, modeling of ecosystems and speciation. They represent my notes for the school "Dynamical Mod...

  14. A Proliferation of Air Pollution Simulation System base on Cellular Automata%基于元胞自动机的污染气体扩散模拟系统

    Institute of Scientific and Technical Information of China (English)

    秦弋丰; 杨雨诚; 谢育武; 李俚; 吴皆强

    2015-01-01

    元胞自动机模型( Cellular Automation Model, CA模型)是一种用于模拟离散动力系统内部的各独立单元间因为强烈非线性作用而引发的系统自组织演化过程的建模方式,规则的局部性和时空离散化是CA模型的主要特征.本系统基于当今城市最为严重的空气污染问题展开研究,主要通过在地图上确定污染源位置,并录入污染源数据,通过元胞自动机原理,模拟在有风和无风状态下污染气体元胞的运动状况,从微观到宏观,系统地描述污染气体的运动状况.%Cellular Automation Model(CA) is a modeling method used to simulate the internal unit between discrete dynamic system that caused the evolution of a self-organization in system because of nonlinear function. Temporal discretization and local rule is it main feature. We developed this system according to the one of the most serious problems of our city in these days which is air pollution. By pain point the source of pollution on the map and input the pollution data, through the principle of the Cellular automata, stimulated the movement of pollution gas cell under condition of both windy calm. Describe the motion of the pollution gas from micro to macro.

  15. Imbalance between apoptosis and cell proliferation during early stages of mammary gland carcinogenesis in ACI rats

    International Nuclear Information System (INIS)

    Estrogen and ionizing radiation are well-documented human breast carcinogens, yet the exact mechanisms of their deleterious effects on mammary gland remain to be discerned. Here we analyze the balance between cellular proliferation and apoptosis in the mammary glands of rats exposed to estrogen and X-ray radiation and the combined action of these carcinogenic agents. For the first time, we show that combined exposure to estrogen and radiation has a synergistic effect on cell proliferation in the mammary glands of ACI rats, as evidenced by a substantially greater magnitude of cell proliferation, especially after 12 and 18 weeks of treatment, when compared to mammary glands of rats exposed to estrogen or radiation alone. We also demonstrate that an imbalance between cell proliferation and apoptosis, rather than enhanced cell proliferation or apoptosis suppression alone, may be a driving force for carcinogenesis. Our studies further suggest that compromised functional activity of p53 may be one of the mechanisms responsible for the proliferation/apoptosis imbalance. In sum, the results of our study indicate that evaluation of the extent of cell proliferation and apoptosis before the onset of preneoplastic lesions may be a potential biomarker of breast cancer risk after exposure to breast carcinogens.

  16. Imbalance between apoptosis and cell proliferation during early stages of mammary gland carcinogenesis in ACI rats

    Energy Technology Data Exchange (ETDEWEB)

    Kutanzi, Kristy R.; Koturbash, Igor [Department of Biological Sciences, University of Lethbridge, Lethbridge, AB, T1K3M4 (Canada); Bronson, Roderick T. [Department of Pathology, Harvard Medical School, 77 Avenue Louis Pasteur, Boston, MA 02115 (United States); Pogribny, Igor P., E-mail: igor.pogribny@fda.hhs.gov [Division of Biochemical Toxicology, National Center for Toxicological Research, Jefferson, AR 72079 (United States); Kovalchuk, Olga, E-mail: olga.kovalchuk@uleth.ca [Department of Biological Sciences, University of Lethbridge, Lethbridge, AB, T1K3M4 (Canada)

    2010-12-10

    Estrogen and ionizing radiation are well-documented human breast carcinogens, yet the exact mechanisms of their deleterious effects on mammary gland remain to be discerned. Here we analyze the balance between cellular proliferation and apoptosis in the mammary glands of rats exposed to estrogen and X-ray radiation and the combined action of these carcinogenic agents. For the first time, we show that combined exposure to estrogen and radiation has a synergistic effect on cell proliferation in the mammary glands of ACI rats, as evidenced by a substantially greater magnitude of cell proliferation, especially after 12 and 18 weeks of treatment, when compared to mammary glands of rats exposed to estrogen or radiation alone. We also demonstrate that an imbalance between cell proliferation and apoptosis, rather than enhanced cell proliferation or apoptosis suppression alone, may be a driving force for carcinogenesis. Our studies further suggest that compromised functional activity of p53 may be one of the mechanisms responsible for the proliferation/apoptosis imbalance. In sum, the results of our study indicate that evaluation of the extent of cell proliferation and apoptosis before the onset of preneoplastic lesions may be a potential biomarker of breast cancer risk after exposure to breast carcinogens.

  17. TAp73 promotes anti-senescence-anabolism not proliferation

    Science.gov (United States)

    Agostini, Massimiliano; Niklison-Chirou, Maria Victoria; Catani, Maria Valeria; Knight, Richard A.; Melino, Gerry; Rufini, Alessandro

    2014-01-01

    TAp73, a member of the p53 family, has been traditionally considered a tumor suppressor gene, but a recent report has claimed that it can promote cellular proliferation. This assumption is based on biochemical evidence of activation of anabolic metabolism, with enhanced pentose phosphate shunt (PPP) and nucleotide biosynthesis. Here, while we confirm that TAp73 expression enhances anabolism, we also substantiate its role in inhibiting proliferation and promoting cell death. Hence, we would like to propose an alternative interpretation of the accumulating data linking p73 to cellular metabolism: we suggest that TAp73 promotes anabolism to counteract cellular senescence rather than to support proliferation. PMID:25554796

  18. Markers of cellular senescence. Telomere shortening as a marker of cellular senescence.

    Science.gov (United States)

    Bernadotte, Alexandra; Mikhelson, Victor M; Spivak, Irina M

    2016-01-01

    The cellular senescence definition comes to the fact of cells irreversible proliferation disability. Besides the cell cycle arrest, senescent cells go through some morphological, biochemical, and functional changes which are the signs of cellular senescence. The senescent cells (including replicative senescence and stress-induced premature senescence) of all the tissues look alike. They are metabolically active and possess the set of characteristics in vitro and in vivo, which are known as biomarkers of aging and cellular senescence. Among biomarkers of cellular senescence telomere shortening is a rather elegant frequently used biomarker. Validity of telomere shortening as a marker for cellular senescence is based on theoretical and experimental data. PMID:26805432

  19. Cellular resilience.

    Science.gov (United States)

    Smirnova, Lena; Harris, Georgina; Leist, Marcel; Hartung, Thomas

    2015-01-01

    Cellular resilience describes the ability of a cell to cope with environmental changes such as toxicant exposure. If cellular metabolism does not collapse directly after the hit or end in programmed cell death, the ensuing stress responses promote a new homeostasis under stress. The processes of reverting "back to normal" and reversal of apoptosis ("anastasis") have been studied little at the cellular level. Cell types show astonishingly similar vulnerability to most toxicants, except for those that require a very specific target, metabolism or mechanism present only in specific cell types. The majority of chemicals triggers "general cytotoxicity" in any cell at similar concentrations. We hypothesize that cells differ less in their vulnerability to a given toxicant than in their resilience (coping with the "hit"). In many cases, cells do not return to the naive state after a toxic insult. The phenomena of "pre-conditioning", "tolerance" and "hormesis" describe this for low-dose exposures to toxicants that render the cell more resistant to subsequent hits. The defense and resilience programs include epigenetic changes that leave a "memory/scar" - an alteration as a consequence of the stress the cell has experienced. These memories might have long-term consequences, both positive (resistance) and negative, that contribute to chronic and delayed manifestations of hazard and, ultimately, disease. This article calls for more systematic analyses of how cells cope with toxic perturbations in the long-term after stressor withdrawal. A technical prerequisite for these are stable (organotypic) cultures and a characterization of stress response molecular networks. PMID:26536287

  20. Modeling and cellular studies

    International Nuclear Information System (INIS)

    Testing the applicability of mathematical models with carefully designed experiments is a powerful tool in the investigations of the effects of ionizing radiation on cells. The modeling and cellular studies complement each other, for modeling provides guidance for designing critical experiments which must provide definitive results, while the experiments themselves provide new input to the model. Based on previous experimental results the model for the accumulation of damage in Chlamydomonas reinhardi has been extended to include various multiple two-event combinations. Split dose survival experiments have shown that models tested to date predict most but not all the observed behavior. Stationary-phase mammalian cells, required for tests of other aspects of the model, have been shown to be at different points in the cell cycle depending on how they were forced to stop proliferating. These cultures also demonstrate different capacities for repair of sublethal radiation damage

  1. Upregulation of PRDM5 Is Associated with Astrocyte Proliferation and Neuronal Apoptosis Caused by Lipopolysaccharide.

    Science.gov (United States)

    Zhang, Yu; Liu, Xiaojuan; Xue, Huaqing; Liu, Xiaorong; Dai, Aihua; Song, Yan; Ke, Kaifu; Cao, Maohong

    2016-05-01

    PRDM5 (PR domain containing 5) belongs to PRDM family which consists of transcriptional regulators that modulate cellular processes such as cell growth, differentiation and apoptosis. However, the function of PRDM5 in central nervous system (CNS) inflammatory response is unknown. In recent study, an adult rat neuroinflammation model via lipopolysaccharide (LPS) lateral ventricle injection was constructed. PRDM5 expression was increased in activated astrocytes and apoptotic neurons of the adult rat cerebral cortex after LPS injection. In vitro studies showed that the remarkable upregulation of PRDM5 might be involved in rat primary astrocyte proliferation and rat primary neuronal apoptosis in the cerebral cortex following LPS administration. In addition, using PRDM5 RNA interference both in rat primary asrtocytes and neurons, further indicated that PRDM5 was required for astrocyte proliferation and neuronal apoptosis induced by LPS. Our findings on the cellular signaling pathway may provide a new therapeutic strategy against neuroinflammation in the CNS. PMID:27074744

  2. Activation of Signal Transducer and Activator of Transcription 5 (STAT5) in Splenocyte Proliferation of Asthma Mice Induced by Ovalbumin

    Institute of Scientific and Technical Information of China (English)

    Guoping Li; Zhigang Liu; Peixing Ran; Jing Qiu; Nanshan Zhong

    2004-01-01

    To investigate the role of signal transducer and transcriptional activator 5 (STAT5) activated in ovalbumin (OVA)-induced splenocyte proliferation of asthma mice, an asthma mouse model was set up by intraperitoneal injection and aspiration of OVA with nebulizer. The proliferation of splenocytes isolated from the asthma mice was detected by [3H] thymidine incorporation. The phosphorytation of STAT5 was examined by Western blotting and STAT5-DNA binding was measured by electrophoretic mobility shift assay (EMSA). OVA could pronouncedly induce the splenocyte proliferation of asthma mice in a dose-dependent manner compared with control groups. Phosphorylation of STAT5 and STAT5-DNA binding were observed in splenocytes from asthma mice induced by OVA at 1 h and 3 h. These results indicated that STAT5 signal pathway played an important role in lymphocyte proliferation of asthma mice induced by OVA. Cellular & Molecular Immunology.2004;1(6):471-474.

  3. A genome-wide systematic analysis reveals different and predictive proliferation expression signatures of cancerous vs. non-cancerous cells.

    Directory of Open Access Journals (Sweden)

    Yedael Y Waldman

    Full Text Available Understanding cell proliferation mechanisms has been a long-lasting goal of the scientific community and specifically of cancer researchers. Previous genome-scale studies of cancer proliferation determinants have mainly relied on knockdown screens aimed to gauge their effects on cancer growth. This powerful approach has several limitations such as off-target effects, partial knockdown, and masking effects due to functional backups. Here we employ a complementary approach and assign each gene a cancer Proliferation Index (cPI that quantifies the association between its expression levels and growth rate measurements across 60 cancer cell lines. Reassuringly, genes found essential in cancer gene knockdown screens exhibit significant positive cPI values, while tumor suppressors exhibit significant negative cPI values. Cell cycle, DNA replication, splicing and protein production related processes are positively associated with cancer proliferation, while cellular migration is negatively associated with it - in accordance with the well known "go or grow" dichotomy. A parallel analysis of genes' non-cancerous proliferation indices (nPI across 224 lymphoblastoid cell lines reveals surprisingly marked differences between cancerous and non-cancerous proliferation. These differences highlight genes in the translation and spliceosome machineries as selective cancer proliferation-associated proteins. A cross species comparison reveals that cancer proliferation resembles that of microorganisms while non-cancerous proliferation does not. Furthermore, combining cancerous and non-cancerous proliferation signatures leads to enhanced prediction of patient outcome and gene essentiality in cancer. Overall, these results point to an inherent difference between cancerous and non-cancerous proliferation determinants, whose understanding may contribute to the future development of novel cancer-specific anti-proliferative drugs.

  4. Histone gene expression remains coupled to DNA synthesis during in vitro cellular senescence

    International Nuclear Information System (INIS)

    Despite a decrease in the extent to which confluent monolayers of late compared to early passage CF3 human diploid fibroblasts can be stimulated to proliferate, the time course of DNA synthesis onset is similar regardless of the in vitro age of the cells. A parallel and stoichiometric relationship is maintained between the rate of DNA synthesis and the cellular levels of histone mRNA independent of the age of the cell cultures. Furthermore, DNA synthesis and cellular histone mRNA levels decline in a coordinate manner after inhibition of DNA replication by hydroxyurea treatment. These results indicate that while the proliferative activity of human diploid fibroblasts decreases with passage in culture, those cells that retain the ability to proliferate continue to exhibit a tight coupling of DNA replication and histone gene expression

  5. Integrating mitochondrial translation into the cellular context.

    Science.gov (United States)

    Richter-Dennerlein, Ricarda; Dennerlein, Sven; Rehling, Peter

    2015-10-01

    Mitochondrial-encoded subunits of the oxidative phosphorylation system assemble with nuclear-encoded subunits into enzymatic complexes. Recent findings showed that mitochondrial translation is linked to other mitochondrial functions, as well as to cellular processes. The supply of mitochondrial-encoded proteins is coordinated by the coupling of mitochondrial protein synthesis with assembly of respiratory chain complexes. MicroRNAs imported from the cytoplasm into mitochondria were, surprisingly, found to act as regulators of mitochondrial translation. In turn, translation in mitochondria controls cellular proliferation, and mitochondrial ribosomal subunits contribute to the cytoplasmic stress response. Thus, translation in mitochondria is apparently integrated into cellular processes. PMID:26535422

  6. An integrative genomic and transcriptomic analysis reveals potential targets associated with cell proliferation in uterine leiomyomas

    DEFF Research Database (Denmark)

    Cirilo, Priscila Daniele Ramos; Marchi, Fábio Albuquerque; Barros Filho, Mateus de Camargo;

    2013-01-01

    integrated analysis identified the top 30 significant genes (P<0.01), which comprised genes associated with cancer, whereas the protein-protein interaction analysis indicated a strong association between FANCA and BRCA1. Functional in silico analysis revealed target molecules for drugs involved in cell...... transcriptomic approach indicated that FGFR1 and IGFBP5 amplification, as well as the consequent up-regulation of the protein products, plays an important role in the aetiology of ULs and thus provides data for potential drug therapies development to target genes associated with cellular proliferation in ULs....

  7. Progressive effects of N-myc deficiency on proliferation, neurogenesis, and morphogenesis in the olfactory epithelium.

    Science.gov (United States)

    Wittmann, Walter; Schimmang, Thomas; Gunhaga, Lena

    2014-06-01

    N-myc belongs to the myc proto-oncogene family, which is involved in numerous cellular processes such as proliferation, growth, apoptosis, and differentiation. Conditional deletion of N-myc in the mouse nervous system disrupted brain development, indicating that N-myc plays an essential role during neural development. How the development of the olfactory epithelium and neurogenesis within are affected by the loss of N-myc has, however, not been determined. To address these issues, we examined an N-myc(Foxg1Cre) conditional mouse line, in which N-myc is depleted in the olfactory epithelium. First changes in N-myc mutants were detected at E11.5, with reduced proliferation and neurogenesis in a slightly smaller olfactory epithelium. The phenotype was more pronounced at E13.5, with a complete lack of Hes5-positive progenitor cells, decreased proliferation, and neurogenesis. In addition, stereological analyses revealed reduced cell size of post-mitotic neurons in the olfactory epithelium, which contributed to a smaller olfactory pit. Furthermore, we observed diminished proliferation and neurogenesis also in the vomeronasal organ, which likewise was reduced in size. In addition, the generation of gonadotropin-releasing hormone neurons was severely reduced in N-myc mutants. Thus, diminished neurogenesis and proliferation in combination with smaller neurons might explain the morphological defects in the N-myc depleted olfactory structures. Moreover, our results suggest an important role for N-myc in regulating ongoing neurogenesis, in part by maintaining the Hes5-positive progenitor pool. In summary, our results provide evidence that N-myc deficiency in the olfactory epithelium progressively diminishes proliferation and neurogenesis with negative consequences at structural and cellular levels. PMID:24376126

  8. Amine functionalized nanodiamond promotes cellular adhesion, proliferation and neurite outgrowth

    International Nuclear Information System (INIS)

    In this study, we report the production of amine functionalized nanodiamond. The amine functionalized nanodiamond forms a conformal monolayer on a negatively charged surface produced via plasma polymerization of acrylic acid. Nanodiamond terminated surfaces were studied as substrates for neuronal cell culture. NG108-15 neuroblastoma-glyoma hybrid cells were successfully cultured upon amine functionalized nanodiamond coated surfaces for between 1 and 7 d. Additionally, primary dorsal root ganglion (DRG) neurons and Schwann cells isolated from Wistar rats were also successfully cultured over a period of 21 d illustrating the potential of the coating for applications in the treatment of peripheral nerve injury. (paper)

  9. Cellular proliferation and regeneration following tissue damage. Progress report. [Eyes

    Energy Technology Data Exchange (ETDEWEB)

    Harding, C.V.

    1976-10-01

    Results are reported from a study of wound healing in tissues of the eye, particularly lens, cornea, and surrounding tissues. The reactions of these tissues to mechanical injuries, as well as injuries induced by chemotoxic agents were studied. It is postulated that a better understanding of the basic reactions of the eye to injurious agents may be of importance in the evaluation of potential environmental hazards.

  10. Suppression of cellular proliferation by the papillomavirus E2 protein.

    OpenAIRE

    Dowhanick, J J; McBride, A A; Howley, P M

    1995-01-01

    Carcinogenic progression of a human papillomavirus (HPV)-infected cell is often associated with integration of the viral genome in a manner which results in the loss of expression of the viral regulatory protein E2. One function of E2 is the regulation of expression of the viral oncogenes, E6 and E7. Introduction of the bovine papillomavirus type 1 (BPV-1) E2 transactivator (E2-TA) in HeLa cells, an HPV type 18 (HPV-18)-positive cervical carcinoma cell line results in growth arrest. In this s...

  11. Cellular proliferation and regeneration following tissue damage. Progress report

    International Nuclear Information System (INIS)

    Studies were conducted on the following research projects: effects of x radiation on rabbit lenses; DNA synthesis and mitosis in cultured lenses; serum dependency and actinomycin D sensitivity; changes in ultrastructure; injury-induced growth of vascular endothelium; corneal neovascularization following injury; and human cataractous lenses

  12. Active Cellular Nematics

    Science.gov (United States)

    Duclos, Guillaume; Erlenkaemper, Christoph; Garcia, Simon; Yevick, Hannah; Joanny, Jean-François; Silberzan, Pascal; Biology inspired physics at mesoscales Team; Physical approach of biological problems Team

    We study the emergence of a nematic order in a two-dimensional tissue of apolar elongated fibroblast cells. Initially, these cells are very motile and the monolayer is characterized by giant density fluctuations, a signature of far-from-equilibrium systems. As the cell density increases because of proliferation, the cells align with each other forming large perfectly oriented domains while the cellular movements slow down and eventually freeze. Therefore topological defects characteristic of nematic phases remain trapped at long times, preventing the development of infinite domains. By analogy with classical non-active nematics, we have investigated the role of boundaries and we have shown that cells confined in stripes of width smaller than typically 500 µm are perfectly aligned in the stripe direction. Experiments performed in cross-shaped patterns show that both the number of cells and the degree of alignment impact the final orientation. Reference: Duclos G., Garcia S., Yevick H.G. and Silberzan P., ''Perfect nematic order in confined monolayers of spindle-shaped cells'', Soft Matter, 10, 14, 2014

  13. Effects of Low-Intensity Ultrasound on Cell Proliferation and Reproductivity

    Institute of Scientific and Technical Information of China (English)

    杨春梅; 蒋学慧; 杜康; 蔡启亮

    2016-01-01

    Ultrasound has been widely used in clinics. Cellular responses to low-intensity ultrasound are parame-ter-dependent. Proper parameter setting is vital to its exact use. To get guidelines for parameter setting, low-intensity ultrasound stimulation on the proliferation and reproductivity of HepG2 and 3T3 cells in vitro was exam-ined with a 1.06 MHz-generator by changing the parameters(including intensity, pulse repetition frequency and duty cycle)in a wide range. Cell viability and reproductivity at different time after sonication were measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT)and colony formation assay to indicate time-related proliferation. The results illustrate that ultrasound irradiation at 0.4—0.8 W/cm2 and high pulse repetition frequency(100 Hz)can facilitate cell proliferation, while above 0.8 W/cm2 would resist it. The extent of resistance closely correlated with duty cycle and pulse repetition frequency. Resistance effect at low pulse repetition fre-quency(1 Hz)is greater than that at high pulse repetition frequency(100 Hz)and not time-related. The influence of high pulse repetition frequency is time-accumulated, indicating cellular process involved. These findings would provide valuable guidelines for the application of low-intensity ultrasound in stem cell transformation and tissue engineering.

  14. Activation of Signal Transducer and Activator of Transcription 5 (STAT5) in Splenocyte Proliferation of Asthma Mice Induced by Ovalbumin

    Institute of Scientific and Technical Information of China (English)

    GuopingLi; ZhigangLiu; PeixingRan; JingQiu; NanshanZhong

    2004-01-01

    To investigate the role of signal transducer and transcriptional activator 5 (STAT5) activated in ovalbumin (OVA)-induced splenocyte proliferation of asthma mice, an asthma mouse model was set up by intraperitoneal injection and aspiration of OVA with nebulizer. The proliferation of splenocytes isolated from the asthma mice was detected by [3H] thymidine incorporation. The phosphorytation of STAT5 was examined by Western blotting and STAT5-DNA binding was measured by electrophoretic mobility shift assay (EMSA). OVA could pronouncedly induce the splenocyte proliferation of asthma mice in a dose-dependent manner compared with control groups. Phosphorylation of STAT5 and STAT5-DNA binding were observed in splenocytes from asthma mice induced by OVA at 1 h and 3 h. These results indicated that STAT5 signal pathway played an important role in lymphocyte proliferation of asthma mice induced by OVA. Cellular & Molecular Immunology.2004;1(6):471-474.

  15. Indicators and signatures

    International Nuclear Information System (INIS)

    Full text: The goal of this presentation is to give an idea of the methodology used to deal with proliferation problems. It can be useful for chemical, biological, balistical proliferation. Here, we underline nuclear proliferation scenarios. Nevertheless, the overall approach is also similar to activities related to terrorism. Everyone knows that to strengthen the NPT/IAEA safeguards and similar treaties verification protocols, the organisations in charge need to build strong capabilities to assess known situations and also to prepare themselves to unknown, or undeclared events and activities. To accomplish this, to collect, analyze, build ad hoc knowledge, organisations have to select the information, to manage the enormous amount of available data. Rather recently, the emergence of new crisis has confirmed the central and vital role that information processing plays at each levels of the international or national non-proliferation community. It is why looking for indicators and signatures is so important, to focus on pertinent information, that could mean something from a nuclear proliferation perspective. This allows people dealing with nuclear proliferation not to be overwhelmed by tons of paper or G bites of memory. A strong need for expertise. Identifying, select and following indicators or looking for signatures is not an easy task. It requires strong expertise. From the development and maintenance of its nuclear deterrence, France acquired expertise in the design, production of fissile material, manufacture and testing of nuclear weapons. There is also in France a long history of nuclear achievements, with small or large scale facilities, both in civilian and military fields; each step of the nuclear fuel cycle can be very precisely described. French nuclear technical assessment relies on Commissariat a l'Energie Atomique (CEA, i.e. Atomic Energy Commission). Since 1958, CEA laboratories are in charge of nuclear civilian and military applications. Other

  16. Proliferation: myth or reality?

    International Nuclear Information System (INIS)

    This article analyzes the proliferation approach, its technical condition and political motivation, and the share between the myth (political deception, assumptions and extrapolations) and the reality of proliferation. Its appreciation is complicated by the irrational behaviour of some political actors and by the significant loss of the non-use taboo. The control of technologies is an important element for proliferation slowing down but an efficient and autonomous intelligence system remains indispensable. (J.S.)

  17. IGF-I enhances cellular senescence via the reactive oxygen species-p53 pathway

    Energy Technology Data Exchange (ETDEWEB)

    Handayaningsih, Anastasia-Evi; Takahashi, Michiko; Fukuoka, Hidenori; Iguchi, Genzo; Nishizawa, Hitoshi; Yamamoto, Masaaki; Suda, Kentaro [Division of Diabetes and Endocrinology, Department of Internal Medicine, Kobe University Graduate School of Medicine, Kobe (Japan); Takahashi, Yutaka, E-mail: takahash@med.kobe-u.ac.jp [Division of Diabetes and Endocrinology, Department of Internal Medicine, Kobe University Graduate School of Medicine, Kobe (Japan)

    2012-08-24

    Highlights: Black-Right-Pointing-Pointer Cellular senescence plays an important role in tumorigenesis and aging process. Black-Right-Pointing-Pointer We demonstrated IGF-I enhanced cellular senescence in primary confluent cells. Black-Right-Pointing-Pointer IGF-I enhanced cellular senescence in the ROS and p53-dependent manner. Black-Right-Pointing-Pointer These results may explain the underlying mechanisms of IGF-I involvement in tumorigenesis and in regulation of aging. -- Abstract: Cellular senescence is characterized by growth arrest, enlarged and flattened cell morphology, the expression of senescence-associated {beta}-galactosidase (SA-{beta}-gal), and by activation of tumor suppressor networks. Insulin-like growth factor-I (IGF-I) plays a critical role in cellular growth, proliferation, tumorigenesis, and regulation of aging. In the present study, we show that IGF-I enhances cellular senescence in mouse, rat, and human primary cells in the confluent state. IGF-I induced expression of a DNA damage marker, {gamma}H2AX, the increased levels of p53 and p21 proteins, and activated SA-{beta}-gal. In the confluent state, an altered downstream signaling of IGF-I receptor was observed. Treatment with a reactive oxygen species (ROS) scavenger, N-acetylcystein (NAC) significantly suppressed induction of these markers, indicating that ROS are involved in the induction of cellular senescence by IGF-I. In p53-null mouse embryonic fibroblasts, the IGF-I-induced augmentation of SA-{beta}-gal and p21 was inhibited, demonstrating that p53 is required for cellular senescence induced by IGF-I. Thus, these data reveal a novel pathway whereby IGF-I enhances cellular senescence in the ROS and p53-dependent manner and may explain the underlying mechanisms of IGF-I involvement in tumorigenesis and in regulation of aging.

  18. Dietary restriction, cell proliferation and carcinogenesis: a preliminary study

    International Nuclear Information System (INIS)

    Four groups of female Swiss Webster mice were given either laboratory chow or a purified (semi-synthetic) diet (AIN-76A) either ad libitum or at 75% of the ad libitum rate for about 30 days. Three tissues, the crypt cells of the jejunum, the dermis and the basal epithelial cells of the esophagus were investigated using [3H]thymidine labelling and by counting mitoses; four other tissues, the alveolar cells of the mammary gland, the crypt cells of the duodenum and colo-rectum, and the transitional cells of the urinary bladder were examined using [3H]thymidine labelling only. In each case dietary restriction led to a reduction of cellular proliferation assessed by these indices. The potential of the approach for the study of the effects of dietary modification on the introduction of cancer is discussed. (author). 22 refs

  19. Differential Cellular and Molecular Effects of Butyrate and Trichostatin A on Vascular Smooth Muscle Cells

    Directory of Open Access Journals (Sweden)

    Kasturi Ranganna

    2012-09-01

    Full Text Available The histone deacetylase (HDAC inhibitors, butyrate and trichostatin A (TSA, are epigenetic histone modifiers and proliferation inhibitors by downregulating cyclin D1, a positive cell cycle regulator, and upregulating p21Cip1 and INK family of proteins, negative cell cycle regulators. Our recent study indicated cyclin D1 upregulation in vascular smooth muscle cells (VSMC that are proliferation-arrested by butyrate. Here we investigate whether cyclin D1 upregulation is a unique response of VSMC to butyrate or a general response to HDAC inhibitors (HDACi by evaluating the effects of butyrate and TSA on VSMC. While butyrate and TSA inhibit VSMC proliferation via cytostatic and cytotoxic effects, respectively, they downregulate cdk4, cdk6, and cdk2, and upregulate cyclin D3, p21Cip1 and p15INK4B, and cause similar effects on key histone H3 posttranslational modifications. Conversely, cyclin D1 is upregulated by butyrate and inhibited by TSA. Assessment of glycogen synthase 3-dependent phosphorylation, subcellular localization and transcription of cyclin D1 indicates that differential effects of butyrate and TSA on cyclin D1 levels are linked to disparity in cyclin D1 gene expression. Disparity in butyrate- and TSA-induced cyclin D1 may influence transcriptional regulation of genes that are associated with changes in cellular morphology/cellular effects that these HDACi confer on VSMC, as a transcriptional modulator.

  20. Proliferation of pulmonary artery smooth muscle cells in the development of ascites syndrome in broilers induced by low ambient temperature.

    Science.gov (United States)

    Wang, J; Qiao, J; Zhao, L H; Li, K; Wang, H; Xu, T; Tian, Y; Gao, M; Wang, X

    2007-12-01

    Pulmonary vascular remodelling, mainly characterized by arterial medial thickening, is an important pathological feature of broiler ascites syndrome (AS). Since vascular smooth muscle cells (VSMC) form the major cellular component of arterial medial layer, we speculate that VSMC proliferation is one of the causes of pulmonary arterial medial thickening in ascitic broilers. Hence, the present study was designed to investigate the role of VSMC proliferation in pulmonary vascular remodelling in development of AS induced by low ambient temperature. Broilers in control group (22 +/- 1.5 degrees C) and low temperature group (11 +/- 2 degrees C) were sampled every week at 15-50 days of age. Proliferative indexes of VSMC in pulmonary arteries were assessed with proliferating cell nuclear antigen, and the relative medial thickness (RMT) and relative wall area (RWA), as indexes of pulmonary vascular remodelling, were examined by computer-image analysing system. The results showed that the high incidence (18.75%) of AS was induced by low temperature, and a significantly increased VSMC proliferation was observed in pulmonary arteries in the low temperature group at 22-50 days of age (P < 0.05). In addition, RMT and RWA in pulmonary arteries were significantly elevated in the low temperature group from 36 days of age (P < 0.05), indicating that pulmonary vascular remodelling occurred following VSMC proliferation in AS. Our data suggest that proliferation of VSMC may facilitate pulmonary vascular remodelling and have a pivotal role in AS induced by low ambient temperature. PMID:18045340

  1. Exosomes Secreted by Toxoplasma gondii-Infected L6 Cells: Their Effects on Host Cell Proliferation and Cell Cycle Changes

    Science.gov (United States)

    Kim, Min Jae; Jung, Bong-Kwang; Cho, Jaeeun; Song, Hyemi; Pyo, Kyung-Ho; Lee, Ji Min; Kim, Min-Kyung; Chai, Jong-Yil

    2016-01-01

    Toxoplasma gondii infection induces alteration of the host cell cycle and cell proliferation. These changes are not only seen in directly invaded host cells but also in neighboring cells. We tried to identify whether this alteration can be mediated by exosomes secreted by T. gondii-infected host cells. L6 cells, a rat myoblast cell line, and RH strain of T. gondii were selected for this study. L6 cells were infected with or without T. gondii to isolate exosomes. The cellular growth patterns were identified by cell counting with trypan blue under confocal microscopy, and cell cycle changes were investigated by flow cytometry. L6 cells infected with T. gondii showed decreased proliferation compared to uninfected L6 cells and revealed a tendency to stay at S or G2/M cell phase. The treatment of exosomes isolated from T. gondii-infected cells showed attenuation of cell proliferation and slight enhancement of S phase in L6 cells. The cell cycle alteration was not as obvious as reduction of the cell proliferation by the exosome treatment. These changes were transient and disappeared at 48 hr after the exosome treatment. Microarray analysis and web-based tools indicated that various exosomal miRNAs were crucial for the regulation of target genes related to cell proliferation. Collectively, our study demonstrated that the exosomes originating from T. gondii could change the host cell proliferation and alter the host cell cycle. PMID:27180572

  2. Effect of molecular weight and concentration of hyaluronan on cell proliferation and osteogenic differentiation in vitro

    International Nuclear Information System (INIS)

    Hyaluronan (HA), the simplest glycosaminoglycan and a major component of the extracellular matrix, exists in various tissues. It is involved in some critical biological procedures, including cellular signaling, cell adhesion and proliferation, and cell differentiation. The effect of molecular weight (MW) and concentration of HA on cell proliferation and differentiation was controversial. In this study, we investigated the effect of MW and concentration of HA on the proliferation and osteogenic differentiation of rabbit bone marrow-derived stem cells in vitro. Results showed that high MW HA decreased the cell adhesion rate in a concentration-dependant manner. The cell adhesion rate was decreased by increasing MW of HA. Cell proliferation was significantly enhanced by low MW HA (P < 0.05). The factorial analysis indicated that MW and concentration had an interactive effect on the cell adhesion rate and cell proliferation (P < 0.05). High MW HA increased the mRNA expressions of ALP, RUNX-2 and OCN. The higher the MW was, the higher the mRNA expressions were. The factorial analysis indicated that MW and concentration had an interactive effect on ALP mRNA expression (P < 0.05). HA of higher MW and higher concentration promoted bone formation. These findings provide some useful information in understanding the mechanism underlying the effect of MW and concentration of HA on cell proliferation and differentiation. - Highlights: • Effect of hyaluronan on cell proliferation and differentiation is evaluated in vitro. • Hyaluronan of low molecular weight increases cell proliferation. • Hyaluronan of high molecular weight promotes cell osteogenic differentiation. • Molecular weight and concentration of hyaluronan show interactive effect

  3. Effect of molecular weight and concentration of hyaluronan on cell proliferation and osteogenic differentiation in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Ningbo, E-mail: curl-zhao@163.com; Wang, Xin, E-mail: 394041230@qq.com; Qin, Lei, E-mail: qinlei30@126.com; Guo, Zhengze, E-mail: zhzeguo@163.com; Li, Dehua, E-mail: lidehuafmmu@163.com

    2015-09-25

    Hyaluronan (HA), the simplest glycosaminoglycan and a major component of the extracellular matrix, exists in various tissues. It is involved in some critical biological procedures, including cellular signaling, cell adhesion and proliferation, and cell differentiation. The effect of molecular weight (MW) and concentration of HA on cell proliferation and differentiation was controversial. In this study, we investigated the effect of MW and concentration of HA on the proliferation and osteogenic differentiation of rabbit bone marrow-derived stem cells in vitro. Results showed that high MW HA decreased the cell adhesion rate in a concentration-dependant manner. The cell adhesion rate was decreased by increasing MW of HA. Cell proliferation was significantly enhanced by low MW HA (P < 0.05). The factorial analysis indicated that MW and concentration had an interactive effect on the cell adhesion rate and cell proliferation (P < 0.05). High MW HA increased the mRNA expressions of ALP, RUNX-2 and OCN. The higher the MW was, the higher the mRNA expressions were. The factorial analysis indicated that MW and concentration had an interactive effect on ALP mRNA expression (P < 0.05). HA of higher MW and higher concentration promoted bone formation. These findings provide some useful information in understanding the mechanism underlying the effect of MW and concentration of HA on cell proliferation and differentiation. - Highlights: • Effect of hyaluronan on cell proliferation and differentiation is evaluated in vitro. • Hyaluronan of low molecular weight increases cell proliferation. • Hyaluronan of high molecular weight promotes cell osteogenic differentiation. • Molecular weight and concentration of hyaluronan show interactive effect.

  4. Chronic exposure of juvenile rats to environmental noise impairs hippocampal cell proliferation in adulthood

    Directory of Open Access Journals (Sweden)

    Fernando Jáuregui-Huerta

    2011-01-01

    Full Text Available Increasing evidence indicates that chronic exposure to environmental noise may permanently affect the central nervous system. The aim of this study was to evaluate the long-term effects of early exposure to environmental noise on the hippocampal cell proliferation of the adult male rat. Early-weaned Wistar rats were exposed for 15 days to a rats′ audiogram-fitted adaptation to a noisy environment. Two months later, the rats were injected with the cellular proliferation marker 5΄bromodeoxiuridine (BrdU, and their brains were processed for immunohistochemical analysis. Coronal sections were immunolabeled with anti-BrdU antibodies to identify new-born cells in dentate gyrus (DG, cornu amonis areas CA1 and CA3. In addition, blood samples were obtained to evaluate corticosterone serum levels after noise exposure. All data are expressed as mean΁standard deviation. For mean comparisons between groups, we used the Student t test. We found an increase in corticosterone serum levels after environmental noise exposure. Interestingly, noise-exposed rats showed a long-term reduction of proliferating cells in the hippocampal formation, as compared to controls. These findings indicate that chronic environmental noise exposure at young ages produces persistent non-auditory impairment that modifies cell proliferation in the hippocampal formation.

  5. Director's series on proliferation

    International Nuclear Information System (INIS)

    This is an occasional publication of essays on the topics of nuclear, chemical, biological, and missile proliferation. The views represented are those of the author's. Essay topics include: Nuclear Proliferation: Myth and Reality; Problems of Enforcing Compliance with Arms Control Agreements; The Unreliability of the Russian Officer Corps: Reluctant Domestic Warriors; and Russia's Nuclear Legacy

  6. Aggregating governance indicators

    OpenAIRE

    Kaufmann, Daniel; Kraay, Aart; Zoido-Lobaton, Pablo

    1999-01-01

    In recent years the growing interest of academics and policymakers in governance has been reflected in the proliferation of cross-country indices measuring various aspects of governance. The authors explain how a simple variant of an unobserved components model can be used to combine the information from these different sources into aggregate governance indicators. The main advantage of this method us that it allows quantification of the precision of both individual sources of governance data...

  7. The use of the tyrosine phosphatase antagonist orthovanadate in the study of a cell proliferation inhibitor

    Science.gov (United States)

    Enebo, D. J.; Hanek, G.; Fattaey, H. K.; Johnson, T. C.; Spooner, B. S. (Principal Investigator)

    1993-01-01

    Incubation of murine fibroblasts with orthovanadate, a global tyrosine phosphatase inhibitor, was shown to confer a "pseudo-transformed" phenotype with regard to cell morphology and growth characteristics. This alteration was manifested by both an increasing refractile appearance of the cells, consistent with many transformed cell lines, as well as an increase in maximum cell density was attained. Despite the abrogation of cellular tyrosine phosphatase activity, orthovanadate-treated cells remained sensitive to the biological activity of a naturally occurring sialoglycopeptide (SGP) cell surface proliferation inhibitor. The results indicated that tyrosine phosphatase activity, inhibited by orthovanadate, was not involved in the signal transduction pathway of the SGP.

  8. Proliferation Networks and Financing

    International Nuclear Information System (INIS)

    The objective of this study is to propose practical solutions aimed at completing and strengthening the existing arrangement for the control of nuclear proliferation through a control of financial as well as material or immaterial flows. In a first part, the author proposes a systemic analysis of networks of suppliers and demanders. He notably evokes the Khan's network and the Iraqi acquisition network during the 1993-2001 period. He also proposes a modelling of proliferation networks (supplier networks and acquisition networks) and of their interactions. In a second part, the author examines possible means and policies aimed at neutralising proliferation networks: organisation, adaptation and improvement of intelligence tools in front of proliferation networks, and means, limitations and perspectives of network neutralisation. He also briefly addresses the possibility of military action to contain proliferation flows

  9. Asparagine promotes cancer cell proliferation through use as an amino acid exchange factor

    Science.gov (United States)

    Krall, Abigail S.; Xu, Shili; Graeber, Thomas G.; Braas, Daniel; Christofk, Heather R.

    2016-01-01

    Cellular amino acid uptake is critical for mTOR complex 1 (mTORC1) activation and cell proliferation. However, the regulation of amino acid uptake is not well-understood. Here we describe a role for asparagine as an amino acid exchange factor: intracellular asparagine exchanges with extracellular amino acids. Through asparagine synthetase knockdown and altering of media asparagine concentrations, we show that intracellular asparagine levels regulate uptake of amino acids, especially serine, arginine and histidine. Through its exchange factor role, asparagine regulates mTORC1 activity and protein synthesis. In addition, we show that asparagine regulation of serine uptake influences serine metabolism and nucleotide synthesis, suggesting that asparagine is involved in coordinating protein and nucleotide synthesis. Finally, we show that maintenance of intracellular asparagine levels is critical for cancer cell growth. Collectively, our results indicate that asparagine is an important regulator of cancer cell amino acid homeostasis, anabolic metabolism and proliferation. PMID:27126896

  10. Multistructural biomimetic substrates for controlled cellular differentiation

    International Nuclear Information System (INIS)

    Multidimensional scaffolds are considered to be ideal candidates for regenerative medicine and tissue engineering based on their potential to provide an excellent microenvironment and direct the fate of the cultured cells. More recently, the use of stem cells in medicine has opened a new technological opportunity for controlled tissue formation. However, the mechanism through which the substrate directs the differentiation of stem cells is still rather unclear. Data concerning its specific surface chemistry, topology, and its signaling ability need to be further understood and analyzed. In our study, atomic force microscopy was used to study the stiffness, roughness, and topology of the collagen (Coll) and metallized collagen (MC) substrates, proposed as an excellent substrate for regenerative medicine. The importance of signaling molecules was studied by constructing a new hybrid signaling substrate that contains both collagen and laminin extracellular matrix (ECM) proteins. The cellular response—such as attachment capability, proliferation and cardiac and neuronal phenotype expression on the metallized and non-metallized hybrid substrates (collagen + laminin)—was studied using MTT viability assay and immunohistochemistry studies. Our findings indicate that such hybrid materials could play an important role in the regeneration of complex tissues. (paper)

  11. Rac1 drives intestinal stem cell proliferation and regeneration

    OpenAIRE

    Myant, K.B.; Scopelliti, A.; Haque, S; Vidal, M; Sansom, O J; Cordero, J.B.

    2013-01-01

    Adult stem cells are responsible for maintaining the balance between cell proliferation and differentiation within self-renewing tissues. The molecular and cellular mechanisms mediating such balance are poorly understood. The production of reactive oxygen species (ROS) has emerged as an important mediator of stem cell homeostasis in various systems. Our recent work demonstrates that Rac1-dependent ROS production mediates intestinal stem cell (ISC) proliferation in mouse models of colorectal c...

  12. Getting serious about proliferation

    International Nuclear Information System (INIS)

    The US needs to give a higher priority to nuclear non-proliferation, but Reagan's policies assume that proliferation is inevitable and that it is more important to be a reliable supplier than to cause trade frictions by trading only with those nations which sign the non-proliferation treaty (NPT). This undercuts US leadership and the intent of the agreement. Several bills now before Congress could help to restore US leadership by tightening export restrictions and the use of plutonium from the US

  13. Cellular factors required for papillomavirus DNA replication.

    OpenAIRE

    Melendy, T; Sedman, J; Stenlund, A

    1995-01-01

    In vitro replication of papillomavirus DNA has been carried out with a combination of purified proteins and partially purified extracts made from human cells. DNA synthesis requires the viral E1 protein and the papillomavirus origin of replication. The E2 protein stimulates DNA synthesis in a binding site-independent manner. Papillomavirus DNA replication is also dependent on the cellular factors replication protein A, replication factor C, and proliferating-cell nuclear antigen as well as a ...

  14. Nicotine as a mitogenic stimulus for pancreatic acinar cell proliferation

    Institute of Scientific and Technical Information of China (English)

    Parimal Chowdhury; Kodetthoor B Udupa

    2006-01-01

    Cell proliferation is an important process in life for growth of normal and cancer cells. The signal transduction pathways activated during this process are strictly regulated. This editorial focuses on the role of nicotine,a mitogen, in the induction of signaling pathways resulting in proliferation of pancreatic tumor cells and compares these events with those in normal acinar cells isolated from the rat pancreas. The data shows striking similarities between these two cellular systems.In addition, the editorial reviews very recent literature of the contribution of MAPK signaling in cell lines associated with human diseases. A prospective cellular model of nicotine induced activation of MAPK cascade is presented.

  15. Electrospun natural-artificial synthetic polymer blended nanofibers and their influence on cellular adhesion,proliferation and migration%静电纺丝天然-人工合成聚合物复合纳米纤维及其对细胞黏附、增殖和迁移的影响

    Institute of Scientific and Technical Information of China (English)

    钱宇娜; 李林昊; 蒋超; 吕永钢; 钟莉; 杨力

    2012-01-01

    生物材料组成成分对细胞生物功能有不同的影响。利用静电纺丝技术制备了基于聚己内酯(PCL,polycaprolactone)的不同天然蛋白、多糖(丝素蛋白(SF,silk fibroin)、透明质酸(HA,hyaluronicacid))的混合组分纳米纤维,采用了扫描电镜和接触角对纳米纤维进行基础表征。同时,进一步考察了纳米纤维作为组织工程支架的可行性。研究结果表明SF组分能增加材料的可纺性,有利于细胞的前期黏附,并能够促进细胞增殖。HA组分可以改善材料的亲水性,增加细胞伪足并促进细胞迁移。重要的是,PCL/SF/HA纳米纤维能同时结合SF和HA的优点,有望在组织工程领域得到应用。%The scaffold compositions played different roles on cellular biological functions.In this study,we developed polycaprolactone(PCL) based nanofibers composed of natural protein and polysaccharides(hyaluronan(HA),silk fibroin(SF)) via electrospinning technology.These nanofibers were characterized by scanning electron microscopy(SEM) and contact angle.Furthermore,we evaluated the potential of different composite nanofibers as tissue engineering scaffolds.In vitro cultivation of human primary skin fibroblasts on the SF-based scaffolds showed a significant increase in cell proliferation.A significant number of cells were found to have well-developed cytoskeleton on PCL/SF nanofibers.Addition of HA component transformed current PCL and PCL/SF components into hydrophilic fibers.Importantly,HA-based scaffolds significantly enhanced cell filopodia protrusions and migration in vitro.PCL/SF/HA nanofibers could combine the advantages of SF and HA.These findings suggest that such multiple blended nanofibers may offer possibilities to tissue engineering application.

  16. Fibronectin adsorption, cell adhesion, and proliferation on nanostructured tantalum surfaces.

    Science.gov (United States)

    Dolatshahi-Pirouz, A; Jensen, T; Kraft, David Christian; Foss, Morten; Kingshott, Peter; Hansen, John Lundsgaard; Larsen, Arne Nylandsted; Chevallier, Jacques; Besenbacher, Flemming

    2010-05-25

    The interaction between dental pulp derived mesenchymal stem cells (DP-MSCs) and three different tantalum nanotopographies with and without a fibronectin coating is examined: sputter-coated tantalum surfaces with low surface roughness tantalum surfaces were examined, as well as cellular attachment, proliferation, and vinculin focal adhesion spot assembly on the respective surfaces. The results showed the highest fibronectin mass uptake on the hut structures, with a slightly higher availability of cell-binding domains and the most pronounced formation of vinculin focal adhesion spots as compared to the other surfaces. The proliferation of DP-MSCs was found to be significantly higher on dome and hut surfaces coated with fibronectin compared to the uncoated flat tantalum surfaces. Consequently, the results presented in this study indicate that fibronectin-coated nanotopographies with a vertical dimension of less than 5 nm influence cell adhesion. This rather interesting behavior is argued to originate from the more available fibronectin cell-binding domains observed on the hut structures. PMID:20443575

  17. Malignant Proliferating Trichilemmal Tumor in the Right Post Auricular Region

    Institute of Scientific and Technical Information of China (English)

    Lihong Cao; Huifang Zhou; Hua Chen

    2006-01-01

    OBJECTIVE To report a case of a malignant proliferating trichilemmal tumor (PTT) in the right postauricular region, and to describe the clinical and histopathologic findings.METHODS Interventional case report and literature review.RESULTS A 46-year-old woman presented with a 15-year history of a nodule of 30×30×10 mm in diameter in the right postauricular region. It was diagnosed as a sebaceous cyst. A local mass excision was performed. Histopathologic examination revealed proliferation of the outer hair sheath epithelium with multiple central areas of trichilemmal keratinization. The presence of marked cellular atypia and frequent mitoses indicated a malignant transformation. A second operation employing an enlarged excision was conducted followed by a histopathologic examination showing that there was no malignant tumor remaining. Two weeks after the second operation, 50 cGy of regional prophylactic radiotherapy was applied. The patient was well after 26 months of follow-up and neither recurrences nor metastases were observed.CONCLUSION Malignant PTT is a rare skin neoplasm, with its diagnosis depending on a histopathologic examination. An extend excision is the main treatment after diagnosis.

  18. Biodiesel from soybean promotes cell proliferation in vitro.

    Science.gov (United States)

    Gioda, Adriana; Rodríguez-Cotto, Rosa I; Amaral, Beatriz Silva; Encarnación-Medina, Jarline; Ortiz-Martínez, Mario G; Jiménez-Vélez, Braulio D

    2016-08-01

    Toxicological responses of exhaust emissions of biodiesel are different due to variation in methods of generation and the tested biological models. A chemical profile was generated using ICP-MS and GC-MS for the biodiesel samples obtained in Brazil. A cytotoxicity assay and cytokine secretion experiments were evaluated in human bronchial epithelial cells (BEAS-2B). Cells were exposed to polar (acetone) and nonpolar (hexane) extracts from particles obtained from fuel exhaust: fossil diesel (B5), pure soybean biodiesel (B100), soybean biodiesel with additive (B100A) and ethanol additive (EtOH). Biodiesel and its additives exhibited higher organic and inorganic constituents on particles when compared to B5. The biodiesel extracts did not exert any toxic effect at concentrations 10, 25, 50, 75, and 100μgmL(-1). In fact quite the opposite, a cell proliferation effect induced by the B100 and B100A extracts is reported. A small increase in concentrations of inflammatory mediators (Interleukin-6, IL-6; and Interleukin-8, IL-8) in the medium of biodiesel-treated cells was observed, however, no statistical difference was found. An interesting finding indicates that the presence of metals in the nonpolar (hexane) fraction of biodiesel fuel (B100) represses cytokine release in lung cells. This was revealed by the use of the metal chelator. Results suggest that metals associated with biodiesel's organic constituents might play a significant role in molecular mechanisms associated to cellular proliferation and immune responses. PMID:27179667

  19. Cytokine signaling for proliferation, survival, and death in hematopoietic cells.

    Science.gov (United States)

    Miyajima, A; Ito, Y; Kinoshita, T

    1999-04-01

    The survival, proliferation, and differentiation of hematopoietic cells are regulated by cytokines. In the absence of cytokines, hematopoietic cells not only stop proliferation, but undergo apoptosis. This strict dependency of hematopoietic cells on cytokines is an important mechanism that maintains the homeostasis of blood cells. Cytokines induce various intracellular signaling pathways by activating the receptor-associated Janus kinases (Jaks), and distinct signals are responsible for cell cycle progression and cell survival. Induction of signals for cell cycle progression without suppressing apoptosis results in apoptotic cell death, indicating the essential role of anti-apoptotic signaling for cell growth. In hematopoietic cells, Ras, a cellular protooncogen product, and phosphatidylinositol 3 kinase are involved in the suppression of apoptosis. Cytokine depletion not only turns off anti-apoptotic signaling, but also actively induces cell death by activating caspases, a distinct family of cysteine proteases. Alterations in the mechanisms of cytokine signaling for cell cycle progression and anti-apoptotic function are implicated in hematological disorders. PMID:10222650

  20. Fibroblast growth factor receptor 3 effects on proliferation and telomerase activity in sheep growth plate chondrocytes

    Directory of Open Access Journals (Sweden)

    Smith Logan B

    2012-12-01

    Full Text Available Abstract Background Fibroblast growth factor receptor 3 (FGFR3 inhibits growth-plate chondrocyte proliferation and limits bone elongation. Gain-of-function FGFR3 mutations cause dwarfism, reduced telomerase activity and shorter telomeres in growth plate chondroyctes suggesting that FGFR3 reduces proliferative capacity, inhibits telomerase, and enhances senescence. Thyroid hormone (T3 plays a role in cellular maturation of growth plate chondrocytes and a known target of T3 is FGFR3. The present study addressed whether reduced FGFR3 expression enhanced telomerase activity, mRNA expression of telomerase reverse transcriptase (TERT and RNA component of telomerase (TR, and chondrocyte proliferation, and whether the stimulation of FGFR3 by T3 evoked the opposite response. Results Sheep growth-plate proliferative zone chondrocytes were cultured and transfected with siRNA to reduce FGFR3 expression; FGFR3 siRNA reduced chondrocyte FGFR3 mRNA and protein resulting in greater proliferation and increased TERT mRNA expression and telomerase activity (p 3 significantly enhanced FGFR3 mRNA and protein expression and reduced telomerase activity (p 3 at the growth plate may be partially mediated through the FGFR3 pathway. Conclusions The results suggest that FGFR3 inhibits chondrocyte proliferation by down-regulating TERT expression and reducing telomerase activity indicating an important role for telomerase in sustaining chondrocyte proliferative capacity during bone elongation.

  1. PLLA/HA Nano composite scaffolds for stem cell proliferation and differentiation in tissue engineering

    Directory of Open Access Journals (Sweden)

    Fariba Mansourizadeh

    2013-03-01

    Full Text Available Due to their mulitpotency, Mesenchymal stem cells (MSCs, have the ability to proliferate and differentiate into multiple mesodermal tissues. The aim of this study was to isolate MSCs from human Umbilical Cord (hUCMSCs to determine their osteogenic potential on nanofibrous scaffolds. To this end, Poly (L-lactic acid (PLLA/Nano hydroxyapatite (HA composite nanofibrous scaffolds were prepared by electrospinning. The structure and morphology of the scaffolds were investigated using scanning electron microscopy. Human mesenchymal stem cells (MSCs were isolated from the umbilical cords and cultured in the PLLA/HA scaffold. The viability and proliferation of the cells was then determined by an MTT assay. Cellular adhesion, proliferation and osteogenic differentiation were assessed in these constructs using a range of histological and microscopic techniques. The osteogenesis assays indicated the superiority of nanofibrous scaffolds in supporting MSCs undergoing bone differentiation. Collectively, the bone construct prepared with PLLA/HA scaffold and proliferated MSCs would be a suitable candidate for use in bone regenerative medicine.

  2. PLLA/HA Nano composite scaffolds for stem cell proliferation and differentiation in tissue engineering

    Directory of Open Access Journals (Sweden)

    Fariba Mansourizadeh

    2013-01-01

    Full Text Available Due to their mulitpotency, Mesenchymal stem cells (MSCs, have the ability to proliferate and differentiate into multiple mesodermal tissues. The aim of this study was to isolate MSCs from human Umbilical Cord (hUCMSCs to determine their osteogenic potential on nanofibrous scaffolds. To this end, Poly (L-lactic acid (PLLA/Nano hydroxyapatite (HA composite nanofibrous scaffolds were prepared by electrospinning. The structure and morphology of the scaffolds were investigated using scanning electron microscopy. Human mesenchymal stem cells (MSCs were isolated from the umbilical cords and cultured in the PLLA/HA scaffold. The viability and proliferation of the cells was then determined by an MTT assay. Cellular adhesion, proliferation and osteogenic differentiation were assessed in these constructs using a range of histological and microscopic techniques. The osteogenesis assays indicated the superiority of nanofibrous scaffolds in supporting MSCs undergoing bone differentiation. Collectively, the bone construct prepared with PLLA/HA scaffold and proliferated MSCs would be a suitable candidate for use in bone regenerative medicine.

  3. Scaffold architecture and fibrin gels promote meniscal cell proliferation

    International Nuclear Information System (INIS)

    Stability of the knee relies on the meniscus, a complex connective tissue with poor healing ability. Current meniscal tissue engineering is inadequate, as the signals for increasing meniscal cell proliferation have not been established. In this study, collagen scaffold structure, isotropic or aligned, and fibrin gel addition were tested. Metabolic activity was promoted by fibrin addition. Cellular proliferation, however, was significantly increased by both aligned architectures and fibrin addition. None of the constructs impaired collagen type I production or triggered adverse inflammatory responses. It was demonstrated that both fibrin gel addition and optimized scaffold architecture effectively promote meniscal cell proliferation

  4. Scaffold architecture and fibrin gels promote meniscal cell proliferation

    Energy Technology Data Exchange (ETDEWEB)

    Pawelec, K. M., E-mail: pawelec.km@gmail.com, E-mail: jw626@cam.ac.uk; Best, S. M.; Cameron, R. E. [Cambridge Centre for Medical Materials, Materials Science and Metallurgy Department, University of Cambridge, Cambridge CB3 0FS (United Kingdom); Wardale, R. J., E-mail: pawelec.km@gmail.com, E-mail: jw626@cam.ac.uk [Division of Trauma and Orthopaedic Surgery, Department of Surgery, University of Cambridge, Cambridge CB2 2QQ (United Kingdom)

    2015-01-01

    Stability of the knee relies on the meniscus, a complex connective tissue with poor healing ability. Current meniscal tissue engineering is inadequate, as the signals for increasing meniscal cell proliferation have not been established. In this study, collagen scaffold structure, isotropic or aligned, and fibrin gel addition were tested. Metabolic activity was promoted by fibrin addition. Cellular proliferation, however, was significantly increased by both aligned architectures and fibrin addition. None of the constructs impaired collagen type I production or triggered adverse inflammatory responses. It was demonstrated that both fibrin gel addition and optimized scaffold architecture effectively promote meniscal cell proliferation.

  5. The Tumorigenic Roles of the Cellular REDOX Regulatory Systems

    OpenAIRE

    Stéphanie Anaís Castaldo; Joana Raquel Freitas; Nadine Vasconcelos Conchinha; Patrícia Alexandra Madureira

    2016-01-01

    The cellular REDOX regulatory systems play a central role in maintaining REDOX homeostasis that is crucial for cell integrity, survival, and proliferation. To date, a substantial amount of data has demonstrated that cancer cells typically undergo increasing oxidative stress as the tumor develops, upregulating these important antioxidant systems in order to survive, proliferate, and metastasize under these extreme oxidative stress conditions. Since a large number of chemotherapeutic agents cur...

  6. The potassium ion channel opener NS1619 inhibits proliferation and induces apoptosis in A2780 ovarian cancer cells

    International Nuclear Information System (INIS)

    Diverse types of voltage-gated potassium (K+) channels have been shown to be involved in regulation of cell proliferation. The maxi-conductance Ca2+-activated K+ channels (BK channels) may play an important role in the progression of human cancer. To explore the role of BK channels in regulation of apoptosis in human ovarian cancer cells, the effects of the specific BK channel activator NS1619 on induction of apoptosis in A2780 cells were observed. Following treatment with NS1619, cell proliferation was measured by MTT assay. Apoptosis of A2780 cells pretreated with NS1619 was detected by agarose gel electrophoresis of cellular DNA and flow cytometry. Our data demonstrate that NS1619 inhibits the proliferation of A2780 cells in a dosage and time dependent manner IC50 = 31.1 μM, for 48 h pretreatment and induces apoptosis. Western blot analyses showed that the anti-proliferation effect of NS1619 was associated with increased expression of p53, p21, and Bax. These results indicate that BK channels play an important role in regulating proliferation of human ovarian cancer cells and may induce apoptosis through induction of p21Cip1 expression in a p53-dependent manner

  7. Transgenic expression of Telomerase reverse transcriptase (Tert) improves cell proliferation of primary cells and enhances reprogramming efficiency into the induced pluripotent stem cell.

    Science.gov (United States)

    Hidema, Shizu; Fukuda, Tomokazu; Date, Shiori; Tokitake, Yuko; Matsui, Yasuhisa; Sasaki, Hiroki; Nishimori, Katsuhiko

    2016-10-01

    The enzymatic activity of telomerase is important for the extension of the telomere repeat sequence and overcoming cellular senescence. We generated a conditional transgenic mouse line, carrying the telomerase reverse transcriptase (Tert) expression cassette, controlled by the Cre-loxP-mediated recombination. In our study, Cre recombinase expression efficiently activated Tert expression, resulting in its increased enzymatic activity, which extended the period of cellular proliferation until the keratinocytes entered senescence. This suggests that transgenic Tert expression is effective in enhancing primary cell proliferation. Notably, Tert expression increased colony formation of induced pluripotent stem (iPS) cells after the introduction of four reprogramming factors, Oct-4, klf4, SOX-2, and c-Myc into the transgenic fibroblasts. To the best of our knowledge, this is the first study to show that the transgenic Tert expression enhances reprogramming efficiency of iPS cells, which indicates a critical role for Tert in the reprogramming process. PMID:27297181

  8. In vitro cellular response to hydroxyapatite scaffolds with oriented pore architectures

    International Nuclear Information System (INIS)

    The objective of the present work was to evaluate the in vitro cellular response to hydroxyapatite (HA) scaffolds with oriented pore architectures. Hydroxyapatite scaffolds with approximately the same porosity (65-70%) but two different oriented microstructures, described as 'columnar' (pore diameter = 90-110 μm) and 'lamellar' (pore width = 20-30 μm), were prepared by unidirectional freezing of suspensions. The response of murine MLO-A5 cells, an osteogenic cell line, to these scaffolds was evaluated using assays of MTT hydrolysis, alkaline phosphatase (ALP) activity, and alizarin red staining. While the cellular response to both groups of scaffolds was better than control wells, the columnar scaffolds with the larger pore width provided the most favorable substrate for cell proliferation and function. These results indicate that HA scaffolds with the columnar microstructure could be used for bone repair applications in vivo.

  9. Magnesium regulates neural stem cell proliferation in the mouse hippocampus by altering mitochondrial function.

    Science.gov (United States)

    Jia, Shanshan; Mou, Chengzhi; Ma, Yihe; Han, Ruijie; Li, Xue

    2016-04-01

    In the adult brain, neural stem cells from the subgranular zone (SGZ) of the hippocampus and the subventricular zone (SVZ) of the cortex progress through the following five developmental stages: radial glia-like cells, neural progenitor cells, neuroblasts, immature neurons, and mature neurons. These developmental stages are linked to both neuronal microenvironments and energy metabolism. Neurogenesis is restricted and has been demonstrated to arise from tissue microenvironments. We determined that magnesium, a key nutrient in cellular energy metabolism, affects neural stem cell (NSC) proliferation in cells derived from the embryonic hippocampus by influencing mitochondrial function. Densities of proliferating cells and NSCs both showed their highest values at 0.8 mM [Mg(2+) ]o , whereas lower proliferation rates were observed at 0.4 and 1.4 mM [Mg(2+) ]o . The numbers and sizes of the neurospheres reached the maximum at 0.8 mM [Mg(2+) ]o and were weaker under both low (0.4 mM) and high (1.4 mM) concentrations of magnesium. In vitro experimental evidence demonstrates that extracellular magnesium regulates the number of cultured hippocampal NSCs, affecting both magnesium homeostasis and mitochondrial function. Our findings indicate that the effect of [Mg(2+) ]o on NSC proliferation may lie downstream of alterations in mitochondrial function because mitochondrial membrane potential was highest in the NSCs in the moderate [Mg(2+) ]o (0.8 mM) group and lower in both the low (0.4 mM) and high (1.4 mM) [Mg(2+) ]o groups. Overall, these findings demonstrate a new function for magnesium in the brain in the regulation of hippocampal neural stem cells: affecting their cellular energy metabolism. PMID:26634890

  10. Cellular senescence as the causal nexus of aging

    Directory of Open Access Journals (Sweden)

    Naina eBhatia-Dey

    2016-02-01

    Full Text Available We present cellular senescence as the ultimate driver of the aging process, as a causal nexus that bridges microscopic subcellular damage with the phenotypic, macroscopic effect of aging. It is important to understand how the various types of subcellular damage correlated with the aging process lead to the larger, visible effects of anatomical aging. While it has always been assumed that subcellular damage (cause results in macroscopic aging (effect, the bridging link between the two has been hard to define. Here, we propose that this bridge, which we term the causal nexus, is in fact cellular senescence. The subcellular damage itself does not directly cause the visible signs of aging, but rather, as the damage accumulates and reaches a critical mass, cells cease to proliferate and acquire the deleterious senescence-associated secretory phenotype (SASP which then leads to the macroscopic consequences of tissue breakdown to create the physiologically aged phenotype. Thus senescence is a precondition for anatomical aging, and this explains why aging is a gradual process that remains largely invisible during most of its progression. The subcellular damage includes shortening of telomeres, damage to mitochondria, aneuploidy and DNA double-strand breaks triggered by various genetic, epigenetic, and environmental factors. Damage pathways acting in isolation or in concert converge at the causal nexus of cellular senescence. In each species some types of damage can be more causative than in others and operate at a variable pace; for example, telomere erosion appears to be a primary cause in human cells, whereas activation of tumor suppressor genes is more causative in rodents. Such species-specific mechanisms indicate that despite different initial causes, most of aging is traced to a single convergent causal nexus: senescence. The exception is in some invertebrate species that escape senescence, and in nondividing cells such as neurons, where

  11. Accelerated cellular senescence phenotype of GAPDH-depleted human lung carcinoma cells

    Energy Technology Data Exchange (ETDEWEB)

    Phadke, Manali; Krynetskaia, Natalia [Temple University School of Pharmacy, Philadelphia, PA 19140 (United States); Mishra, Anurag [Jayne Haines Center for Pharmacogenomics, Temple University School of Pharmacy, Philadelphia, PA 19140 (United States); Krynetskiy, Evgeny, E-mail: ekrynets@temple.edu [Temple University School of Pharmacy, Philadelphia, PA 19140 (United States); Jayne Haines Center for Pharmacogenomics, Temple University School of Pharmacy, Philadelphia, PA 19140 (United States)

    2011-07-29

    Highlights: {yields} We examined the effect of glyceraldehyde 3-phosphate (GAPDH) depletion on proliferation of human carcinoma A549 cells. {yields} GAPDH depletion induces accelerated senescence in tumor cells via AMPK network, in the absence of DNA damage. {yields} Metabolic and genetic rescue experiments indicate that GAPDH has regulatory functions linking energy metabolism and cell cycle. {yields} Induction of senescence in LKB1-deficient lung cancer cells via GAPDH depletion suggests a novel strategy to control tumor cell proliferation. -- Abstract: Glyceraldehyde 3-phosphate dehydrogenase (GAPDH) is a pivotal glycolytic enzyme, and a signaling molecule which acts at the interface between stress factors and the cellular apoptotic machinery. Earlier, we found that knockdown of GAPDH in human carcinoma cell lines resulted in cell proliferation arrest and chemoresistance to S phase-specific cytotoxic agents. To elucidate the mechanism by which GAPDH depletion arrests cell proliferation, we examined the effect of GAPDH knockdown on human carcinoma cells A549. Our results show that GAPDH-depleted cells establish senescence phenotype, as revealed by proliferation arrest, changes in morphology, SA-{beta}-galactosidase staining, and more than 2-fold up-regulation of senescence-associated genes DEC1 and GLB1. Accelerated senescence following GAPDH depletion results from compromised glycolysis and energy crisis leading to the sustained AMPK activation via phosphorylation of {alpha} subunit at Thr172. Our findings demonstrate that GAPDH depletion switches human tumor cells to senescent phenotype via AMPK network, in the absence of DNA damage. Rescue experiments using metabolic and genetic models confirmed that GAPDH has important regulatory functions linking the energy metabolism and the cell cycle networks. Induction of senescence in LKB1-deficient non-small cell lung cancer cells via GAPDH depletion suggests a novel strategy to control tumor cell proliferation.

  12. Accelerated cellular senescence phenotype of GAPDH-depleted human lung carcinoma cells

    International Nuclear Information System (INIS)

    Highlights: → We examined the effect of glyceraldehyde 3-phosphate (GAPDH) depletion on proliferation of human carcinoma A549 cells. → GAPDH depletion induces accelerated senescence in tumor cells via AMPK network, in the absence of DNA damage. → Metabolic and genetic rescue experiments indicate that GAPDH has regulatory functions linking energy metabolism and cell cycle. → Induction of senescence in LKB1-deficient lung cancer cells via GAPDH depletion suggests a novel strategy to control tumor cell proliferation. -- Abstract: Glyceraldehyde 3-phosphate dehydrogenase (GAPDH) is a pivotal glycolytic enzyme, and a signaling molecule which acts at the interface between stress factors and the cellular apoptotic machinery. Earlier, we found that knockdown of GAPDH in human carcinoma cell lines resulted in cell proliferation arrest and chemoresistance to S phase-specific cytotoxic agents. To elucidate the mechanism by which GAPDH depletion arrests cell proliferation, we examined the effect of GAPDH knockdown on human carcinoma cells A549. Our results show that GAPDH-depleted cells establish senescence phenotype, as revealed by proliferation arrest, changes in morphology, SA-β-galactosidase staining, and more than 2-fold up-regulation of senescence-associated genes DEC1 and GLB1. Accelerated senescence following GAPDH depletion results from compromised glycolysis and energy crisis leading to the sustained AMPK activation via phosphorylation of α subunit at Thr172. Our findings demonstrate that GAPDH depletion switches human tumor cells to senescent phenotype via AMPK network, in the absence of DNA damage. Rescue experiments using metabolic and genetic models confirmed that GAPDH has important regulatory functions linking the energy metabolism and the cell cycle networks. Induction of senescence in LKB1-deficient non-small cell lung cancer cells via GAPDH depletion suggests a novel strategy to control tumor cell proliferation.

  13. Cellular host responses to gliomas.

    Directory of Open Access Journals (Sweden)

    Joseph Najbauer

    Full Text Available BACKGROUND: Glioblastoma multiforme (GBM is the most aggressive type of malignant primary brain tumors in adults. Molecular and genetic analysis has advanced our understanding of glioma biology, however mapping the cellular composition of the tumor microenvironment is crucial for understanding the pathology of this dreaded brain cancer. In this study we identified major cell populations attracted by glioma using orthotopic rodent models of human glioma xenografts. Marker-specific, anatomical and morphological analyses revealed a robust influx of host cells into the main tumor bed and tumor satellites. METHODOLOGY/PRINCIPAL FINDINGS: Human glioma cell lines and glioma spheroid orthotopic implants were used in rodents. In both models, the xenografts recruited large numbers of host nestin-expressing cells, which formed a 'network' with glioma. The host nestin-expressing cells appeared to originate in the subventricular zone ipsilateral to the tumor, and were clearly distinguishable from pericytes that expressed smooth muscle actin. These distinct cell populations established close physical contact in a 'pair-wise' manner and migrated together to the deeper layers of tumor satellites and gave rise to tumor vasculature. The GBM biopsy xenografts displayed two different phenotypes: (a low-generation tumors (first in vivo passage in rats were highly invasive and non-angiogenic, and host nestin-positive cells that infiltrated into these tumors displayed astrocytic or elongated bipolar morphology; (b high-generation xenografts (fifth passage had pronounced cellularity, were angiogenic with 'glomerulus-like' microvascular proliferations that contained host nestin-positive cells. Stromal cell-derived factor-1 and its receptor CXCR4 were highly expressed in and around glioma xenografts, suggesting their role in glioma progression and invasion. CONCLUSIONS/SIGNIFICANCE: Our data demonstrate a robust migration of nestin-expressing host cells to glioma, which

  14. The nuclear proliferation; La proliferation nucleaire

    Energy Technology Data Exchange (ETDEWEB)

    Gere, F. [Ecole Polytechnique, 91 - Palaiseau (France)

    1995-04-01

    In this book is detailed the beginning of nuclear military power, with the first bomb of Hiroshima, the different ways of getting uranium 235 and plutonium 239, and how the first countries (Usa, Ussr, China, United kingdom, France) got nuclear weapons. Then the most important part is reviewed with the details of non-proliferation treaty and the creation of IAEA to promote civilian nuclear power in the world and to control the use of plutonium and uranium in nuclear power plants. The cases of countries who reached the atom mastery, such Israel, South Africa, Pakistan, Iraq, North Korea, Argentina, Brazil, Iran, Algeria, Taiwan and the reasons which they wanted nuclear weapon for or why they gave up, are exposed.

  15. The atrophy and changes in the cellular compositions of the thymus and spleen observed in mice subjected to short-term exposure to perfluorooctanesulfonate are high-dose phenomena mediated in part by peroxisome proliferator-activated receptor-alpha (PPARα)

    International Nuclear Information System (INIS)

    We have previously shown that short-term, high-dose exposure of mice to the environmentally persistent perfluorooctanoate (PFOA) results in thymic and splenic atrophy and the attenuation of specific humoral immune responses. Here we characterize the effects of a 10-day treatment with different dietary doses (1-0.001%, w/w) of perfluorooctanesulfonate (PFOS), a similar fluorochemical, on the immune system of male C57BL/6 mice. At doses greater than 0.02%, PFOS induced clinical signs of toxicity in the animals, whereas at the concentration of 0.02%, this compound caused weight loss, hepatomegaly and atrophy of the thymus, spleen and adipose tissue without toxicity. With this latter dose, histopathological and flow-cytometric analysis revealed that (i) the thymic cortex was virtually depleted of cells; (ii) the total numbers of thymocytes and splenocytes were reduced by 84 and 43%, respectively; (iii) although all populations of thymocytes and splenocytes were smaller, the thymic CD4+CD8+ cells and the splenic B-lymphocytes were most decreased. These alterations resembled those evoked by analogous exposure to PFOA, but were less pronounced. At lower doses (less than 0.02%), PFOS induced hepatomegaly without affecting the thymus or spleen. Finally, comparison of male wild-type 129/Sv mice and the corresponding knock-outs lacking peroxisome proliferator-activated receptor-alpha (PPARα) indicated that these effects of PFOS are not strain-dependent. More importantly, hepatomegaly is independent of PPARα, the thymic changes are partially dependent on this receptor, and splenic responses are largely eliminated in its absence. Thus, immunomodulation caused by PFOS is a high-dose phenomenon partially dependent on PPARα.

  16. Effects of hierarchical micro/nano-topographies on the morphology, proliferation and differentiation of osteoblast-like cells.

    Science.gov (United States)

    Huang, Qianli; Elkhooly, Tarek A; Liu, Xujie; Zhang, Ranran; Yang, Xing; Shen, Zhijian; Feng, Qingling

    2016-09-01

    Coating the surfaces of titanium-based implants with appropriate hierarchical micro/nano-topographies resembling the structure of natural bone significantly enhances their biological performance. However, the relationship between nanostructures surfaces and their effects on modulating cellular response is not clearly understood. Moreover, it is not clear whether the surface chemistry or topography is the main factor on modulating cellular behavior, because the commonly used surface modification techniques for titanium-based implants simultaneously modify surface topography and chemistry. The aim of this study is to investigate osteoblast-like cell adhesion, proliferation and differentiation on hierarchical micro/nano-topographies with similar surface chemistry but different nano-scale features. Micro-arc oxidation and post hydrothermal treatment were employed to fabricate micro/nano-topographies on titanium. According to the morphological features, they were classified as microcrater (micro-topography), nanoplate (hierarchical topography with nanoplates) and nanoleaf (hierarchical topography with nanoleaves). The response of osteoblast like cells (SaOS-2) was studied on each surface after sputtering with a thin layer of gold (Au) to minimize the influence of surface chemistry. The morphological evaluation after histochemical staining revealed that the adherent cells were polygonal-shaped on microcrater surface, roundish on nanoplate surface and elongated on nanoleaf surface. Additionally, compared to microcrater surface, nanoplate surface slowed down cell proliferation and exhibited no enhancement on cell differentiation. However, nanoleaf surface supported cell proliferation and promoted cell differentiation. The results indicate that tuning morphological features of nanostructures on micro-topography can serve as a promising strategy to specifically modulate cellular response, such as cell morphology, proliferation, differentiation and mineralization. PMID

  17. The role of Rac1 in the regulation of NF-kB activity, cell proliferation, and cell migration in non-small cell lung carcinoma

    Science.gov (United States)

    Gastonguay, Adam; Berg, Tracy; Hauser, Andrew D.; Schuld, Nathan; Lorimer, Ellen; Williams, Carol L.

    2012-01-01

    The small GTPase Rac1 regulates many cellular processes, including cytoskeletal reorganization, cell migration, proliferation, and survival. Additionally, Rac1 plays a major role in activating NF-κB-mediated transcription. Both Rac1 and NF-κB regulate many properties of the malignant phenotype, including anchorage-independent proliferation and survival, metastasis, and angiogenesis. Despite these findings, the roles of Rac1and NF-κB in non-small cell lung carcinoma, a leading cause of cancer deaths, have not been thoroughly investigated. Here, we compared the effects of Rac1 siRNA to that of the Rac1 inhibitor NSC23766 on multiple features of the NSCLC malignant phenotype, including NF-κB activity. We show that the siRNA-mediated silencing of Rac1 in lung cancer cells results in decreased cell proliferation and migration. The decrease in proliferation was observed in both anchorage-dependent and anchorage-independent assays. Furthermore, cells with decreased Rac1 expression have a slowed progression through the G1 phase of the cell cycle. These effects induced by Rac1 siRNA correlated with a decrease in NF-κB transcriptional activity. Additionally, inhibition of NF-κB signaling with BAY 11–7082 inhibited proliferation; indicating that the loss of cell proliferation and migration induced by the silencing of Rac1 expression may be attributed in part to loss of NF-κB activity. Interestingly, treatment with the Rac1 inhibitor NSC23766 strongly inhibits cell proliferation, cell cycle progression, and NF-κB activity in lung cancer cells, to an even greater extent than the inhibition induced by Rac1 siRNA. These findings indicate that Rac1 plays an important role in lung cancer cell proliferation and migration, most likely through its ability to promote NF-κB activity, and highlight Rac1 pathways as therapeutic targets for the treatment of lung cancer. PMID:22549160

  18. Cell Proliferation in Neuroblastoma

    Directory of Open Access Journals (Sweden)

    Laura L. Stafman

    2016-01-01

    Full Text Available Neuroblastoma, the most common extracranial solid tumor of childhood, continues to carry a dismal prognosis for children diagnosed with advanced stage or relapsed disease. This review focuses upon factors responsible for cell proliferation in neuroblastoma including transcription factors, kinases, and regulators of the cell cycle. Novel therapeutic strategies directed toward these targets in neuroblastoma are discussed.

  19. Battling Nuclear Proliferation

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    As the North Korean and Iranian nuclear issues develop and efforts to resolve them continue, global attention to anti-nuclear proliferation and the work of the International Atomic Energy Agency (IAEA) has become even more intense. Pang Sen, Chairman of

  20. Modelling cellular behaviour

    Science.gov (United States)

    Endy, Drew; Brent, Roger

    2001-01-01

    Representations of cellular processes that can be used to compute their future behaviour would be of general scientific and practical value. But past attempts to construct such representations have been disappointing. This is now changing. Increases in biological understanding combined with advances in computational methods and in computer power make it possible to foresee construction of useful and predictive simulations of cellular processes.

  1. MAPK signal pathways in the regulation of cell proliferation in mammalian cells

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    MAPK families play an important role in complex cellular programs like proliferation, differentiation,development, transformation, and apoptosis. At least three MAPK families have been characterized: extracellular signal-regulated kinase (ERK), Jun kinase (JNK/SAPK) and p38 MAPK. The above effects are fulfilled by regulation of cell cycle engine and other cell proliferation related proteins. In this paper we discussed their functions and cooperation with other signal pathways in regulation of cell proliferation.

  2. Leptin augments coronary vasoconstriction and smooth muscle proliferation via a Rho-kinase-dependent pathway.

    Science.gov (United States)

    Noblet, Jillian N; Goodwill, Adam G; Sassoon, Daniel J; Kiel, Alexander M; Tune, Johnathan D

    2016-05-01

    Leptin has been implicated as a key upstream mediator of pathways associated with coronary vascular dysfunction and disease. The purpose of this investigation was to test the hypothesis that leptin modifies the coronary artery proteome and promotes increases in coronary smooth muscle contraction and proliferation via influences on Rho kinase signaling. Global proteomic assessment of coronary arteries from lean swine cultured with obese concentrations of leptin (30 ng/mL) for 3 days revealed significant alterations in the coronary artery proteome (68 proteins) and identified an association between leptin treatment and calcium signaling/contraction (four proteins) and cellular growth and proliferation (35 proteins). Isometric tension studies demonstrated that both acute (30 min) and chronic (3 days, serum-free media) exposure to obese concentrations of leptin potentiated depolarization-induced contraction of coronary arteries. Inhibition of Rho kinase significantly reduced leptin-mediated increases in coronary artery contractions. The effects of leptin on the functional expression of Rho kinase were time-dependent, as acute treatment increased Rho kinase activity while chronic (3 day) exposure was associated with increases in Rho kinase protein abundance. Proliferation assays following chronic leptin administration (8 day, serum-containing media) demonstrated that leptin augmented coronary vascular smooth muscle proliferation and increased Rho kinase activity. Inhibition of Rho kinase significantly reduced these effects of leptin. Taken together, these findings demonstrate that leptin promotes increases in coronary vasoconstriction and smooth muscle proliferation and indicate that these phenotypic effects are associated with alterations in the coronary artery proteome and dynamic effects on the Rho kinase pathway. PMID:26975316

  3. Suppressed proliferation of mouse osteoblast-like cells by a rough-surfaced substrate leads to low differentiation and mineralization

    International Nuclear Information System (INIS)

    The cellular responses of mouse osteoblast-like MC3T3-E1 cells to the surface roughness were examined in the sequential events of cell adhesion, proliferation, differentiation, and mineralization. The cells were plated and cultured on sandblasted borosilicate glass slideslips with different surface roughnesses. DNA synthesis at day 1 after plating and the cell number at day 5 significantly decreased as the surface roughness increased. The suppressed cell proliferation on the rough-surfaced substrates, closely related to the round cell morphology, caused underdeveloped intercellular contacts via the gap junction due to the low population of neighboring cells. Expressions of the representative osteoblastic genes at day 14, alkaline phosphatase activity at day 21, and mineralization at day 28 were markedly reduced on the rough-surfaced substrates. These results clearly indicated that the reduced cell differentiation and mineralization resulted from the early cellular responses of the suppressed cell proliferation depending on the surface roughness and the consequent poor intercellular communication. The specific changes in the early gene expression profiles at day 1, depending on the surface roughness, were examined by a large-scale analysis of the gene expression using a mouse DNA chip. The ribosomal protein S6 kinase polypeptide 1 gene, which is a cell growth-related gene involved in the PI3-kinase/Akt pathway, was found to be the most down-regulated among the 4277 screened genes.

  4. KI-67 PROLIFERATION INDEX AND CLINICOPATHOLOGICAL PATTERNS IN UPPER GASTROINTESTINAL TRACT CARCINOMAS

    Directory of Open Access Journals (Sweden)

    Bhagyalakshmi1,

    2014-03-01

    Full Text Available : BACKGROUND: Neoplasms of upper gastrointestinal tracts are common and one of the leading causes of death worldwide. In India esophageal and gastric cancers are the most common cancers found in men. Thus early detection and evaluation of prognosis by various methods plays an important role in management of patient. Proliferative activity of tumor assessed with respect to Ki- 67 antigen expression is a useful prognostic parameter. This study aimed to correlate the various clinicopathological parameters of upper gastrointestinal tract carcinomas with Ki-67 tumor proliferative activity and to evaluate its prognostic significance. METHODS: This is a prospective study for a period of two years from August 2011 to July 2013 in the department of pathology, Andhra Medical College, Visakhapatnam. The various parameters like patient’s age, sex, cancer site, histological type and differentiation of the tumor were studied. The above parameters were correlated with KI 67 proliferative indices of the respective cancers and were evaluated statistically. Chi-square tests were used for statistical correlation and p value of <0.05 was considered significant. RESULTS: Most common age group for occurrence of upper gastrointestinal carcinomas was from 4th to 6th with majority of patients being males (66%. The most common presenting complaints of esophagus and gastric carcinoma patients was dysphagia and dyspepsia respectively while most common presenting complaint of ampullary carcinoma was jaundice. 39% of the patients were alcoholics and 57% of the patients were smokers. Cellular proliferation as assessed by Ki-67 immunohistochemical staining in esophageal carcinoma showed no correlation with age, sex, site, histological type, and grade of the tumor. In carcinoma stomach, statistically significant correlation was seen between Ki-67 proliferation index (PI and sex and histological type of tumor with males showing higher Ki-67 proliferation index than females

  5. Overexpression of heme oxygenase-1 protects smooth muscle cells against oxidative injury and inhibits cell proliferation

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    To investigate whether the expression of exogenous heme oxygenase-1 (HO-l) gene within vascular smooth muscle cells (VSMC) could protect the cells from free radical attack and inhibit cell proliferation,we established an in vitro transfection of human HO-1 gene into rat VSMC mediated by a retroviral vector.The results showed that the profound expression of HO-1 protein as well as HO activity was 1.8- and 2.0-fold increased respectively in the transfected cells compared to the non-transfected ones. The treatment of VSMC with different concentrations of H2O2 led to the remarkable cell damage as indicated by survival rate and LDH leakage. However, the resistance of the HO-1 transfected VSMC against H2O2 was significantly raised. This protective effect was dramatically diminished when the transfected VSMC were pretreated with ZnPP-IX, a specific inhibitor of HO, for 24 h. In addition, we found that the growth potential of the transfected cells was significantly inhibited directly by increased activity of HO-l, and this effect might be related to decreased phosphorylation of MAPK. These results suggest that the overexpression of introduced hHO-1 is potentially able to reduce the risk factors of atherosclerosis, partially due to its cellular protection against oxidative injury and to its inhibitory effect on cellular proliferation.

  6. Lysosomal Storage Causes Cellular Dysfunction in Mucolipidosis II Skin Fibroblasts*

    Science.gov (United States)

    Otomo, Takanobu; Higaki, Katsumi; Nanba, Eiji; Ozono, Keiichi; Sakai, Norio

    2011-01-01

    Mucolipidosis II (ML-II) is a fatal inherited metabolic disease caused by deficiency of GlcNAc-phosphotransferase, which plays a role in generating the mannose 6-phosphate recognition marker on lysosomal enzymes. In ML-II, many lysosomal acid hydrolases are mistargeted out of cells, and lysosomes become filled with undigested substrates, which explains inclusion cell disease as an alternative name for this disease. In this study, we revealed various cellular phenotypes in ML-II skin fibroblasts. We quantitated phospholipid and cholesterol within cells and showed ∼2-fold accumulation in ML-II as compared with normal cells. Lysosomal pH of ML-II cells was higher than that of normal cells (5.29 ± 0.08 versus 4.79 ± 0.10, p < 0.001). The proliferated lysosomes in ML-II cells were accumulated ∼3-fold in amount as compared with normal cells. Intracellular logistics including endocytosis and mannose 6-phosphate receptor recycling were impaired in ML-II cells. To confirm whether these ML-II cellular phenotypes derive from deficient lysosomal acid hydrolases within lysosomes, we performed supplementation of lysosomal enzymes using a partially purified total enzyme mixture, which was derived from the conditioned culture medium of normal skin fibroblasts after NH4Cl treatment. This supplementation corrected all of the previously described ML-II phenotypes. In addition, the autophagic and mitochondrial impairment that we have previously reported improved, and inclusion bodies disappeared on electron micrography following total lysosomal enzyme supplementation. Our results indicate that various cellular phenotypes in ML-II are caused by the deficiency of many lysosomal enzymes and massive accumulation of undigested substrates. PMID:21846724

  7. Syndecan-4 modulates the proliferation of neural cells and the formation of CaP axons during zebrafish embryonic neurogenesis.

    Science.gov (United States)

    Luo, Ning; Li, Hongda; Xiang, Bo; Qiao, Liangjun; He, Jiao; Ji, Yi; Liu, Yuan; Li, Siying; Lu, Ran; Li, Yu; Meng, Wentong; Wu, Yang; Xu, Hong; Mo, Xianming

    2016-01-01

    Syndecan-4 (Syn4), a single-pass transmembrane heparin sulphate proteoglycan (HSPG), plays significant role in the formation of focal adhesions and interacts with many growth factors to regulate cell migration and neural induction. Here, we show the new roles of syndecan-4(syn4) in zebrafish embryonic neurogenesis. Syn4 is broadly and dynamically expressed throughout the early stages of embryonic development. Knockdown of syn4 increases the expression of the marker genes of multiple types of neural cells. The increased expression of the marker genes is resulted from excessive proliferation of the neural cells. In addition, disrupting syn4 expression results in truncated and multiple aberrant branching of caudal primary (CaP) axons. Collectively, these data indicate that Syn4 suppresses the cellular proliferation during neurogenesis and is crucial for the formation of CaP axons during zebrafish embryogenesis. PMID:27143125

  8. Syndecan-4 modulates the proliferation of neural cells and the formation of CaP axons during zebrafish embryonic neurogenesis

    Science.gov (United States)

    Luo, Ning; Li, Hongda; Xiang, Bo; Qiao, Liangjun; He, Jiao; Ji, Yi; Liu, Yuan; Li, Siying; Lu, Ran; Li, Yu; Meng, Wentong; Wu, Yang; Xu, Hong; Mo, Xianming

    2016-01-01

    Syndecan-4 (Syn4), a single-pass transmembrane heparin sulphate proteoglycan (HSPG), plays significant role in the formation of focal adhesions and interacts with many growth factors to regulate cell migration and neural induction. Here, we show the new roles of syndecan-4(syn4) in zebrafish embryonic neurogenesis. Syn4 is broadly and dynamically expressed throughout the early stages of embryonic development. Knockdown of syn4 increases the expression of the marker genes of multiple types of neural cells. The increased expression of the marker genes is resulted from excessive proliferation of the neural cells. In addition, disrupting syn4 expression results in truncated and multiple aberrant branching of caudal primary (CaP) axons. Collectively, these data indicate that Syn4 suppresses the cellular proliferation during neurogenesis and is crucial for the formation of CaP axons during zebrafish embryogenesis. PMID:27143125

  9. Effect of chloroquine on human lymphocyte proliferation

    DEFF Research Database (Denmark)

    Bygbjerg, Ib Christian; Flachs, H

    1986-01-01

    The effect of chloroquine on human blood mononuclear cells was studied. High concentrations of chloroquine in vitro profoundly suppressed the proliferation of mitogen- and antigen-stimulated cells, as indicated by decreased 14C-thymidine incorporation. Lower concentrations of chloroquine increase...

  10. Spontaneous Proliferation in Organotypic Cultures of Mouse Cochleae

    Institute of Scientific and Technical Information of China (English)

    DING Da-lian; WANG Jian; YU Zhi-ping; JIANG Hai-yan; WANG Ping; Richard Salvi

    2008-01-01

    Cells in mammalian cochleae virtually stop proliferation and exit cellular circle before birth. Consequently, hair cells and spiral ganglion neurons destroyed by ototoxic factors cannot be replaced through proliferative regeneration. However, substantial proliferation occurs in organotypic cultures of cochleae from postnatal mice. In the present study, we studied the time course of proliferative growth in cultures of mouse cochlea explants obtained from up to 12 postnatal days. The mitotic nature of this growth was confirmed by bromodeoxyuridine (BrdU) staining and expression of proliferation cell nuclear antigen (PCNA) evaluated with real-time quantitative polymerase chain reaction(RT-PCR). Similar growth time course was found in the cochlear explants of different postnatal ages. The new growth reached its maximum at around 2 days in culture followed by a slow-down, and virtually stopped after 5 days of culture. The possible mechanisms and the significance of this proliferation are discussed.

  11. Non-proliferation considerations

    International Nuclear Information System (INIS)

    This paper reiterates the Indian viewpoint that consideration of ''proliferation resistance'' is outside the terms of reference of Working Group 4 as agreed at the Washington Conference. The discussions in WG4 should therefore cover only safeguards aspects. The paper goes on to critisize the various assessment factors introduced in INFCE/DEP./WG-4/104 and the various alternative technologies proposed. The Indian view is reinstated that if a country requires reprocessing based on its nuclear energy programmes and priorities, there should be no hindrance. International safeguards should be applied to all nuclear materials in all countries without discrimination or differentiation between civil and military programmes. The paper concludes that non-proliferation is essentially a political matter and has no technical solution

  12. Heterogeneous cellular networks

    CERN Document Server

    Hu, Rose Qingyang

    2013-01-01

    A timely publication providing coverage of radio resource management, mobility management and standardization in heterogeneous cellular networks The topic of heterogeneous cellular networks has gained momentum in industry and the research community, attracting the attention of standardization bodies such as 3GPP LTE and IEEE 802.16j, whose objectives are looking into increasing the capacity and coverage of the cellular networks. This book focuses on recent progresses,  covering the related topics including scenarios of heterogeneous network deployment, interference management i

  13. Cellular Reflectarray Antenna

    Science.gov (United States)

    Romanofsky, Robert R.

    2010-01-01

    The cellular reflectarray antenna is intended to replace conventional parabolic reflectors that must be physically aligned with a particular satellite in geostationary orbit. These arrays are designed for specified geographical locations, defined by latitude and longitude, each called a "cell." A particular cell occupies nominally 1,500 square miles (3,885 sq. km), but this varies according to latitude and longitude. The cellular reflectarray antenna designed for a particular cell is simply positioned to align with magnetic North, and the antenna surface is level (parallel to the ground). A given cellular reflectarray antenna will not operate in any other cell.

  14. In vivo and in vitro analysis of age-associated changes and somatic cellular senescence in renal epithelial cells.

    Directory of Open Access Journals (Sweden)

    Birgit Berkenkamp

    Full Text Available Acute kidney injury is a major clinical problem and advanced age is associated with ineffective renal regeneration and poor functional outcome. Data from kidney injury models suggest that a loss of tubular epithelial proliferation contributes to a decrease in renal repair capacity with aging, but aging can also lead to a higher severity of inflammation and damage which may influence repair. In this study we tested intrinsic age-dependent changes in tubular epithelial proliferation in young and old mice, by injecting low-dose lead acetate as a non-injurious mitogen. In parallel, we explored in vitro techniques of studying cellular senescence in primary tubular epithelial cells (PTEC. Lead acetate induced tubular epithelial proliferation at a significantly higher rate in young as compared to old mice. Old kidneys showed significantly more senescence as demonstrated by increased p16 (INK4a, senescence associated β-galactosidase, and γH2AX(+/Ki-67(- cells. This was paralleled in old kidneys by a higher number of Cyclin D1 positive tubular cells. This finding was corroborated by a positive correlation between Cyclin D1 positivity and age in human renal biopsies. When tubular cells were isolated from mouse kidneys they rapidly lost their age-associated differences under culture conditions. However, senescence was readily induced in PTEC by γ-irradiation representing a future model for study of cellular senescence in the renal epithelium. Together, our data indicate that the tubular epithelium of aged kidney has an intrinsically reduced proliferative capacity probably due to a higher load of senescent cells. Moreover, stress induced models of cellular senescence are preferable for study of the renal epithelium in vitro. Finally, the positive correlation of Cyclin D1 with age and cellular senescence in PTEC needs further evaluation as to a functional role of renal epithelial aging.

  15. Determining Lineage Pathways from Cellular Barcoding Experiments

    Directory of Open Access Journals (Sweden)

    Leïla Perié

    2014-02-01

    Full Text Available Cellular barcoding and other single-cell lineage-tracing strategies form experimental methodologies for analysis of in vivo cell fate that have been instrumental in several significant recent discoveries. Due to the highly nonlinear nature of proliferation and differentiation, interrogation of the resulting data for evaluation of potential lineage pathways requires a new quantitative framework complete with appropriate statistical tests. Here, we develop such a framework, illustrating its utility by analyzing data from barcoded multipotent cells of the blood system. This application demonstrates that the data require additional paths beyond those found in the classical model, which leads us to propose that hematopoietic differentiation follows a loss of potential mechanism and to suggest further experiments to test this deduction. Our quantitative framework can evaluate the compatibility of lineage trees with barcoded data from any proliferating and differentiating cell system.

  16. Proliferation and fission of peroxisomes - An update.

    Science.gov (United States)

    Schrader, Michael; Costello, Joseph L; Godinho, Luis F; Azadi, Afsoon S; Islinger, Markus

    2016-05-01

    In mammals, peroxisomes perform crucial functions in cellular metabolism, signalling and viral defense which are essential to the health and viability of the organism. In order to achieve this functional versatility peroxisomes dynamically respond to molecular cues triggered by changes in the cellular environment. Such changes elicit a corresponding response in peroxisomes, which manifests itself as a change in peroxisome number, altered enzyme levels and adaptations to the peroxisomal structure. In mammals the generation of new peroxisomes is a complex process which has clear analogies to mitochondria, with both sharing the same division machinery and undergoing a similar division process. How the regulation of this division process is integrated into the cell's response to different stimuli, the signalling pathways and factors involved, remains somewhat unclear. Here, we discuss the mechanism of peroxisomal fission, the contributions of the various division factors and examine the potential impact of post-translational modifications, such as phosphorylation, on the proliferation process. We also summarize the signalling process and highlight the most recent data linking signalling pathways with peroxisome proliferation. PMID:26409486

  17. Proliferation after the Iraq war

    International Nuclear Information System (INIS)

    This article uses the Iraq war major event to analyze the approach used by the US to fight against proliferation. It questions the decision and analysis process which has led to the US-British intervention and analyzes the consequences of the war on the proliferation of other countries and on the expected perspectives. Finally, the future of proliferation itself is questioned: do we have to fear more threat or is the virtuous circle of non-proliferation well started? (J.S.)

  18. Latent membrane protein 1 of Epstein-Barr virus coordinately regulates proliferation with control of apoptosis.

    Science.gov (United States)

    Dirmeier, Ulrike; Hoffmann, Reinhard; Kilger, Ellen; Schultheiss, Ute; Briseño, Cinthia; Gires, Olivier; Kieser, Arnd; Eick, Dirk; Sugden, Bill; Hammerschmidt, Wolfgang

    2005-03-01

    Latent membrane protein 1 (LMP1), an oncoprotein encoded by Epstein-Barr virus (EBV), is an integral membrane protein, which acts like a constitutively active receptor. LMP1 is critical for some facet of EBV's induction and maintenance of proliferation of infected B cells. It, in part, mimics signaling by the CD40 receptor and has been implicated in regulating proliferation, survival, or both properties of EBV-infected cells. We established a conditional LMP1 allele in the context of the intact EBV genome to define the immediate-early cellular target genes regulated by LMP1 in order to assess its contributions to infected human B cells. The functional analysis of this conditional system indicated that LMP1 specifically induces mitogenic B-cell activation through c-myc and Jun/AP1 family members and confirms its direct role in upregulating expression of multiple genes with opposing activities involved in cell survival. LMP1's signals were found to be essential for the G1/S transition in human B cells; cells lacking LMP1's signals are cell cycle arrested and survive quiescently. LMP1's activities are therefore not required to maintain survival in nonproliferating cells. LMP1 does induce both pro- and antiapoptotic genes whose balance seems to permit survival during LMP1's induction and maintenance of proliferation. PMID:15674340

  19. Role of aquaporins in cell proliferation: What else beyond water permeability?

    Science.gov (United States)

    Galán-Cobo, Ana; Ramírez-Lorca, Reposo; Echevarría, Miriam

    2016-01-01

    In addition to the extensive data demonstrating the importance of mammalian AQPs for the movement of water and some small solutes across the cell membrane, there is now a growing body of evidence indicating the involvement of these proteins in numerous cellular processes seemingly unrelated, at least some of them in a direct way, to their canonical function of water permeation. Here, we have presented a broad range of evidence demonstrating that these proteins have a role in cell proliferation by various different mechanisms, namely, by allowing fast cell volume regulation during cell division; by affecting progression of cell cycle and helping maintain the balance between proliferation and apoptosis, and by crosstalk with other cell membrane proteins or transcription factors that, in turn, modulate progression of the cell cycle or regulate biosynthesis pathways of cell structural components. In the end, however, after discussing all these data that strongly support a role for AQPs in the cell proliferation process, it remains impossible to conclude that all these other functions attributed to AQPs occur completely independently of their water permeability, and there is a need for new experiments designed specifically to address this interesting issue. PMID:26752515

  20. Role of MXD3 in proliferation of DAOY human medulloblastoma cells.

    Directory of Open Access Journals (Sweden)

    Gustavo A Barisone

    Full Text Available A subset of medulloblastomas, the most common brain tumor in children, is hypothesized to originate from granule neuron precursors (GNPs in which the sonic hedgehog (SHH pathway is over-activated. MXD3, a basic helix-look-helix zipper transcription factor of the MAD family, has been reported to be upregulated during postnatal cerebellar development and to promote GNP proliferation and MYCN expression. Mxd3 is upregulated in mouse models of medulloblastoma as well as in human medulloblastomas. Therefore, we hypothesize that MXD3 plays a role in the cellular events that lead to medulloblastoma biogenesis. In agreement with its proliferative role in GNPs, MXD3 knock-down in DAOY cells resulted in decreased proliferation. Sustained overexpression of MXD3 resulted in decreased cell numbers due to increased apoptosis and cell cycle arrest. Structure-function analysis revealed that the Sin3 interacting domain, the basic domain, and binding to E-boxes are essential for this activity. Microarray-based expression analysis indicated up-regulation of 84 genes and down-regulation of 47 genes. Potential direct MXD3 target genes were identified by ChIP-chip. Our results suggest that MXD3 is necessary for DAOY medulloblastoma cell proliferation. However, increased level and/or duration of MXD3 expression ultimately reduces cell numbers via increased cell death and cell cycle arrest.

  1. Upregulation of KPNβ1 in gastric cancer cell promotes tumor cell proliferation and predicts poor prognosis.

    Science.gov (United States)

    Zhu, Jia; Wang, Yingying; Huang, Hua; Yang, Qichang; Cai, Jing; Wang, Qiuhong; Gu, Xiaoling; Xu, Pan; Zhang, Shusen; Li, Manhua; Ding, Haifang; Yang, Lei

    2016-01-01

    KPNβ1, also known as importin β, P97, is reported as one of soluble transport factors that mediates transportion of proteins and RNAs between the nucleus and cytoplasm in cellular process. Recent studies show that KPNβ1 is a tumor gene which is highly expressed in several malignant tumors such as ovarian cancer, cervical tumor, neck cancer, and lung cancer via promoting cell proliferation or inhibiting cell apoptotic pathways. However, the the role of KPNβ1 in gastric cancer remains unclear. In this study, Western blot and immunohistochemistrical analyses showed that KPNβ1 was significantly upregulated in clinical gastric cancer specimens compared with adjacent noncancerous tissues. KPNβ1 was positively correlated with tumor grade, Ki-67, and predicted poor prognosis of gastric cancer. More importantly, through starvation-refeeding model, CCK8 assay, flow cytometry, colony formation assays, the vitro studies demonstrated that KPNβ1 promoted proliferation of gastric cancer cells, while KPNβ1 knockdown led to decreased cell proliferation and arrested cell cycle at G1 phase. Furthermore, our results also indicated that KPNβ1 expression could result in docetaxel resistance. And, KPNβ1 could interact with Stat1, contributed to its nucleus import in gastric cancer cells. These findings provided a novel promising therapeutic targets for clinical treatment against human gastric cancer. PMID:26242264

  2. Waste indicators

    International Nuclear Information System (INIS)

    The Waste Indicator Project focuses on methods to evaluate the efficiency of waste management. The project proposes the use of three indicators for resource consumption, primary energy and landfill requirements, based on the life-cycle principles applied in the EDIP Project. Trial runs are made With the indicators on paper, glass packaging and aluminium, and two models are identified for mapping the Danish waste management, of which the least extensive focuses on real and potential savings. (au)

  3. Waste indicators

    Energy Technology Data Exchange (ETDEWEB)

    Dall, O.; Lassen, C.; Hansen, E. [Cowi A/S, Lyngby (Denmark)

    2003-07-01

    The Waste Indicator Project focuses on methods to evaluate the efficiency of waste management. The project proposes the use of three indicators for resource consumption, primary energy and landfill requirements, based on the life-cycle principles applied in the EDIP Project. Trial runs are made With the indicators on paper, glass packaging and aluminium, and two models are identified for mapping the Danish waste management, of which the least extensive focuses on real and potential savings. (au)

  4. Quality indicators

    DEFF Research Database (Denmark)

    Hjorth-Andersen, Christian

    1991-01-01

    In recent literature it has been suggested that consumers need have no knowledge of product quality as a number of quality indicators (or signals) may be used as substitutes. Very little attention has been paid to the empirical verification of these studies. The present paper is devoted...... to the issue of how well these indicators perform, using market data provided by consumer magazines from 3 countries. The results strongly indicate that price is a poor quality indicator. The paper also presents some evidence which suggests that seller reputation and easily observable characteristics are also...

  5. Cellular oncogenes in neoplasia.

    OpenAIRE

    Chan, V T; McGee, J O

    1987-01-01

    In recent years cellular homologues of many viral oncogenes have been identified. As these genes are partially homologous to viral oncogenes and are activated in some tumour cell lines they are termed "proto-oncogenes". In tumour cell lines proto-oncogenes are activated by either quantitative or qualitative changes in gene structure: activation of these genes was originally thought to be a necessary primary event in carcinogenesis, but activated cellular oncogenes, unlike viral oncogenes, do ...

  6. Cellular Cardiomyoplasty: Clinical Application

    OpenAIRE

    Chachques, J. (J.); Acar, C; J. Herreros; Trainini, J. (Jorge); Prosper, F.; D’Attellis, N. (N.); Fabiani, J. N.; Carpentier, A

    2004-01-01

    Myocardial regeneration can be induced with the implantation of a variety of myogenic and angiogenic cell types. More than 150 patients have been treated with cellular cardiomyoplasty worldwide, 18 patients have been treated by our group. Cellular cardiomyoplasty seems to reduce the size and fibrosis of infarct scars, limit postischemic remodelling, and restore regional myocardial contractility. Techniques for skeletal myoblasts culture and ex vivo expansion using auto...

  7. Modeling boundary conditions for balanced proliferation in metastatic latency

    Science.gov (United States)

    Taylor, Donald P; Wells, Jakob Z; Savol, Andrej; Chennubhotla, Chakra; Wells, Alan

    2013-01-01

    Purpose Nearly half of cancer metastases become clinically evident five or more years after primary tumor treatment; thus metastatic cells survived without emerging for extended periods. This dormancy has been explained by at least two countervailing scenarios: cellular quiescence and balanced proliferation; these entail dichotomous mechanistic etiologies. To examine the boundary parameters for balanced proliferation, we performed in silico modeling. Experimental Design To illuminate the balanced proliferation hypothesis, we explored the specific boundary probabilities under which proliferating micrometastases would remain dormant. A two-state Markov chain Monte Carlo model simulated micrometastatic proliferation and death according to stochastic survival probabilities. We varied these probabilities across 100 simulated patients each with 1,000 metastatic deposits and documented whether the micrometastases exceeded one million cells, died out, or remained dormant (survived 1,218 generations). Results The simulations revealed a narrow survival probability window (49.7 – 50.8 percent) that allowed for dormancy across a range of starting cell numbers, and even then for only a small fraction of micrometastases. The majority of micrometastases died out quickly even at survival probabilities that led to rapid emergence of a subset of micrometastases. Within dormant metastases, cell populations depended sensitively on small survival probability increments. Conclusions Metastatic dormancy as explained solely by balanced proliferation is bounded by very tight survival probabilities. Considering the far larger survival variability thought to attend fluxing microenvironments, it is more probable that these micrometastatic nodules undergo at least periods of quiescence rather than exclusively being controlled by balanced proliferation. PMID:23329811

  8. Immunometabolism: Cellular Metabolism Turns Immune Regulator.

    Science.gov (United States)

    Loftus, Róisín M; Finlay, David K

    2016-01-01

    Immune cells are highly dynamic in terms of their growth, proliferation, and effector functions as they respond to immunological challenges. Different immune cells can adopt distinct metabolic configurations that allow the cell to balance its requirements for energy, molecular biosynthesis, and longevity. However, in addition to facilitating immune cell responses, it is now becoming clear that cellular metabolism has direct roles in regulating immune cell function. This review article describes the distinct metabolic signatures of key immune cells, explains how these metabolic setups facilitate immune function, and discusses the emerging evidence that intracellular metabolism has an integral role in controlling immune responses. PMID:26534957

  9. Nanomechanics of magnetically driven cellular endocytosis

    Science.gov (United States)

    Zablotskii, V.; Lunov, O.; Dejneka, A.; Jastrabík, L.; Polyakova, T.; Syrovets, T.; Simmet, Th.

    2011-10-01

    Being essential for many pharmacodynamic and pharmacokinetic processes and playing a crucial role in regulating substrate detachment that enables cellular locomotion, endocytotic mechanisms in many aspects still remain a mystery and therefore can hardly be controlled. Here, we report on experimental and modeling studies of the magnetically assisted endocytosis of functionalized superparamagnetic iron oxide nanoparticles by prostate cancer cells (PC-3) and characterize the time and force scales of the cellular uptake machinery. The results indicate how the cellular uptake rate could be controlled by applied magnetic field, membrane elasticity, and nanoparticle magnetic moment.

  10. PPARα: Mechanism of species differences and hepatocarcinogenesis of peroxisome proliferators

    International Nuclear Information System (INIS)

    Peroxisome proliferator chemicals are classic non-genotoxic carcinogens. These agents cause liver cancers when chronically administered to rats and mice. Peroxisome proliferators include the widely prescribed lipid and cholesterol lowering fibrate drugs. In contrast to the results in rodents, there is no evidence that fibrates are associated with elevated risk of liver cancer or any other neoplasms in humans thus indicating a species difference in the hepatocarcinogenic response. The biological effects of peroxisome proliferators are mediated by the peroxisome proliferator-activated receptor (PPAR)α. Pparα-null mice are resistant to all of the pleiotropic effects of peroxisome proliferators, including cell proliferation and hepatocarcinogenesis. The mechanism of hepatocellular proliferation involves downregulation of the microRNA let-7c gene by PPARα. Let-7c controls levels of proliferative c-myc by destabilizing its mRNA. Thus, upon suppression of let-7c, c-myc mRNA and protein are elevated resulting in enhanced hepatocellular proliferation. In contrast, PPARα-humanized mice, that respond to Wy-14,643 by lower serum triglycerides and induction of genes encoding fatty acid metabolizing enzymes, are resistant to peroxisome proliferator-induced cell proliferation and cancer. These mice do not exhibit downregulation of let-7c gene expression thus forming the basis for the resistance to hepatocellular carcinogenesis

  11. Cellular and molecular introduction to brain development.

    Science.gov (United States)

    Jiang, Xiangning; Nardelli, Jeannette

    2016-08-01

    Advances in the study of brain development over the last decades, especially recent findings regarding the evolutionary expansion of the human neocortex, and large-scale analyses of the proteome/transcriptome in the human brain, have offered novel insights into the molecular mechanisms guiding neural maturation, and the pathophysiology of multiple forms of neurological disorders. As a preamble to reviews of this issue, we provide an overview of the cellular, molecular and genetic bases of brain development with an emphasis on the major mechanisms associated with landmarks of normal neural development in the embryonic stage and early postnatal life, including neural stem/progenitor cell proliferation, cortical neuronal migration, evolution and folding of the cerebral cortex, synaptogenesis and neural circuit development, gliogenesis and myelination. We will only briefly depict developmental disorders that result from perturbations of these cellular or molecular mechanisms, and the most common perinatal brain injuries that could disturb normal brain development. PMID:26184894

  12. Israel's position on non-proliferation

    International Nuclear Information System (INIS)

    Israel maintained that the complex international system and worldwide political tension created a situation in which comprehensive plans of disarmament could not produce any positive result. The deadlock in the field of general and complete disarmament has brought Israel to the realization that one possible way to alleviate the stalemate could be progress by stages through partial measures of disarmament. Israel's position on non-proliferation indicates that the establishment of a nuclear-weapon-free-zone (NWFZ), as it relates to the Middle-East, could serve as a credible alternative to the unilateral adherence to the Non-Proliferation of Nuclear Weapon (NPT) and an effective measure of non-proliferation in the region. (Author)

  13. Numb-deficient satellite cells have regeneration and proliferation defects.

    Science.gov (United States)

    George, Rajani M; Biressi, Stefano; Beres, Brian J; Rogers, Erik; Mulia, Amanda K; Allen, Ronald E; Rawls, Alan; Rando, Thomas A; Wilson-Rawls, Jeanne

    2013-11-12

    The adaptor protein Numb has been implicated in the switch between cell proliferation and differentiation made by satellite cells during muscle repair. Using two genetic approaches to ablate Numb, we determined that, in its absence, muscle regeneration in response to injury was impaired. Single myofiber cultures demonstrated a lack of satellite cell proliferation in the absence of Numb, and the proliferation defect was confirmed in satellite cell cultures. Quantitative RT-PCR from Numb-deficient satellite cells demonstrated highly up-regulated expression of p21 and Myostatin, both inhibitors of myoblast proliferation. Transfection with Myostatin-specific siRNA rescued the proliferation defect of Numb-deficient satellite cells. Furthermore, overexpression of Numb in satellite cells inhibited Myostatin expression. These data indicate a unique function for Numb during the initial activation and proliferation of satellite cells in response to muscle injury. PMID:24170859

  14. Highly efficient mesenchymal stem cell proliferation on poly-ε-caprolactone nanofibers with embedded magnetic nanoparticles

    Directory of Open Access Journals (Sweden)

    Daňková J

    2015-12-01

    Full Text Available Jana Danková,1,2 Matej Buzgo,1,3,4 Jana Vejpravová,5 Simona Kubíčková,5 Věra Sovková,1,2 Lucie Vysloužilová,4,6 Alice Mantlíková,5 Alois Nečas,7 Evžen Amler1–31Laboratory of Tissue Engineering, Institute of Experimental Medicine, Academy of Sciences of the Czech Republic, Prague, Czech Republic; 2Institute of Biophysics, Second Faculty of Medicine, Charles University in Prague, Prague, Czech Republic; 3Faculty of Biomedical Engineering, Czech Technical University in Prague, Kladno, Czech Republic; 4University Center for Energy Efficient Buildings, Czech Technical University in Prague, Bustehrad, Czech Republic; 5Department of Magnetic Nanosystems, Institute of Physics, Academy of Sciences of the Czech Republic, Prague, Czech Republic; 6Department of Nonwoven Textiles, Faculty of Textile Engineering, Technical University of Liberec, Liberec, Czech Republic; 7Faculty of Veterinary Medicine, University of Veterinary and Pharmaceutical Sciences Brno, Brno, Czech RepublicAbstract: In this study, we have developed a combined approach to accelerate the proliferation of mesenchymal stem cells (MSCs in vitro, using a new nanofibrous scaffold made by needleless electrospinning from a mixture of poly-ε-caprolactone and magnetic particles. The biological characteristics of porcine MSCs were investigated while cultured in vitro on composite scaffold enriched with magnetic nanoparticles. Our data indicate that due to the synergic effect of the poly-ε-caprolactone nanofibers and magnetic particles, cellular adhesion and proliferation of MSCs is enhanced and osteogenic differentiation is supported. The cellular and physical attributes make this new scaffold very promising for the acceleration of efficient MSC proliferation and regeneration of hard tissues.Keywords: magnetic particles, mesenchymal stem cells, nanofibers, tissue engineering 

  15. Plugging indicator

    International Nuclear Information System (INIS)

    It is often difficult to measure a plugging temperature when the impurity concentration in liquid sodium is low. Then, the plugging temperature is considered to be inferior to 1100C. Sometimes, a more precise indication is required. We propose a use for the plugging indicator which satisfies this type of requirement. A partial plugging of the indicator orifice is produced and increases at a constant temperature. A mathematical model describes this growth: it is based mainly on the kinetics of Na2O and NaH crystal growth and links the plugging time to oxygen or hydrogen concentrations. (orig.)

  16. Molecular and Cellular Evidence for the Alternative Lengthening of Telomeres (ALT) Mechanism in Chicken

    OpenAIRE

    O'Hare, T.H.; Delany, M. E.

    2011-01-01

    Telomere maintenance is an important genetic mechanism controlling cellular proliferation. Normally, telomeres are maintained by telomerase which is downregulated upon cellular differentiation in most somatic cell lineages. Telomerase activity is upregulated in immortalized cells and cancers to support an infinite lifespan and uncontrolled cell growth; however, some immortalized and transformed cells lack telomerase activity. Telomerase-negative tumors and immortalized cells utilize an altern...

  17. Solar Indices

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Collection includes a variety of indices related to solar activity contributed by a number of national and private solar observatories located worldwide. This...

  18. Cellular Dynamics of RNA Modification

    Science.gov (United States)

    Yi, Chengqi; Pan, Tao

    2011-01-01

    Conspectus Decades of research have identified over 100 types of ribonucleosides that are post-transcriptionally modified. Many modified nucleosides are conserved in bacteria, archeae and eukaryotes, while some modified nucleosides are unique to each branch of life. However, the cellular and functional dynamics of RNA modifications remains largely unexplored, mostly due to the lack of functional hypotheses and experimental methods for quantification and large scale analysis. Just as many well characterized protein and DNA modifications, many RNA modifications are not essential for life. Instead, increasingly more evidence indicates that RNA modifications can play regulatory roles in cells, especially in response to stress conditions. In this Account, we review some known examples of RNA modifications that are dynamically controlled in cells and introduce some contemporary technologies and methods that enhance the studies of cellular dynamics of RNA modifications. Examples of RNA modifications discussed in this Account include (Figure 1): (1) 4-thio uridine (s4U) which can act as a cellular sensor of near UV-light; (2) queuosine (Q) which is a potential biomarker for malignancy; (3) N6-methyl adenine (m6A) which is the prevalent modification in eukaryotic mRNAs; and (4) pseudouridine (ψ) which are inducible by nutrient deprivation. Two recent technical advances that stimulated the studies of cellular dynamics of modified ribonucleosides are also described. First, a genome-wide method combines primer extension and microarray to study N1-methyl adenine (m1A) hypomodification in human tRNA. Second, a quantitative mass spectrometric method investigates dynamic changes of a wide range of tRNA modifications under stress conditions in yeast. In addition, we discuss potential mechanisms that control dynamic regulation of RNA modifications, and hypotheses for discovering potential RNA de-modification enzymes. We conclude the Account by highlighting the need to develop new

  19. Non-proliferation

    International Nuclear Information System (INIS)

    The issue of Nuclear Non Proliferation has been moved to a leading place on the contemporary international security agenda. What about the situation of nuclear weapons and nuclear technology in Russia, Kazakhstan, Ukraine and Belorussia? Why did the IAEA-inspectors totally failed to discover any sign of Iraq's clandestine nuclear-weapon programme before the Gulf War? Do the NATO and their nuclear power states violate Art. VI of the Non-Proliferation-Treaty (NPT), because they are - despite the end of the cold war - not willing to renounce of the ''option of the first use of nuclear weapons''? Does the NPT establish a form of nuclear apartheid? What will be the situation if the NPT-Extension-Conference in 1995 will be unable to obtain a majority of the parties for any one extension proposal? Do we need a new international nuclear control agency with severe powers, a sort of nuclear Interpol? The Colloquium ''Saving NPT and abolishing Nuclear Weapons'', held in Stockholm in September 1992, organized by the Swedish and the German Sections of IALANA, tried to analyse some of the raised issues. (orig.)

  20. Non Proliferation of Nuclear

    International Nuclear Information System (INIS)

    Non-Proliferation Treaty of Nuclear Weapons is the international community's efforts to maintain the security of the world, in order to prevent the spread of nuclear technology and the use of nuclear weapons, promoting cooperation for the use of nuclear peaceful purposes, build mutual trust (Confidence Building Measures) as well as to achieve the ultimate goal of disarmament overall (General and Complete Disarmament). Addressing the post-WTC tragedy, 11 September 2001, the Indonesian government should set up a National Measures (National Action Plan), among others formed the National Security Council and NBC Counter Proliferation Unit, or the National Authority for Nuclear Treaty, preparing national legislation, to prevent the abuse nuclear materials for terrorist acts, prevent Illicit Trafficking of Nuclear materials, developed a National Preparedness and Emergency Response Management in the event of a nuclear accident or attack by the use of nuclear terrorism. Importance of a National Action Plan meant the existence of a national commitment in the context of compliance with treaties and conventions which have been ratified relating to safety, security, safeguards towards a general and complete disarmament, to safeguard national security and maintain peace (safeguards) international

  1. Initiatives for proliferation prevention

    International Nuclear Information System (INIS)

    Preventing the proliferation of weapons of mass destruction is a central part of US national security policy. A principal instrument of the Department of Energy's (DOE's) program for securing weapons of mass destruction technology and expertise and removing incentives for scientists, engineers and technicians in the newly independent states (NIS) of the former Soviet Union to go to rogue countries or assist terrorist groups is the Initiatives for Proliferation Prevention (IPP). IPP was initiated pursuant to the 1994 Foreign Operations Appropriations Act. IPP is a nonproliferation program with a commercialization strategy. IPP seeks to enhance US national security and to achieve nonproliferation objectives by engaging scientists, engineers and technicians from former NIS weapons institutes; redirecting their activities in cooperatively-developed, commercially viable non-weapons related projects. These projects lead to commercial and economic benefits for both the NIS and the US IPP projects are funded in Russian, Ukraine, Kazakhstan and Belarus. This booklet offers an overview of the IPP program as well as a sampling of some of the projects which are currently underway

  2. Initiatives for proliferation prevention

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-04-01

    Preventing the proliferation of weapons of mass destruction is a central part of US national security policy. A principal instrument of the Department of Energy`s (DOE`s) program for securing weapons of mass destruction technology and expertise and removing incentives for scientists, engineers and technicians in the newly independent states (NIS) of the former Soviet Union to go to rogue countries or assist terrorist groups is the Initiatives for Proliferation Prevention (IPP). IPP was initiated pursuant to the 1994 Foreign Operations Appropriations Act. IPP is a nonproliferation program with a commercialization strategy. IPP seeks to enhance US national security and to achieve nonproliferation objectives by engaging scientists, engineers and technicians from former NIS weapons institutes; redirecting their activities in cooperatively-developed, commercially viable non-weapons related projects. These projects lead to commercial and economic benefits for both the NIS and the US IPP projects are funded in Russian, Ukraine, Kazakhstan and Belarus. This booklet offers an overview of the IPP program as well as a sampling of some of the projects which are currently underway.

  3. EZH2 depletion blocks the proliferation of colon cancer cells.

    Directory of Open Access Journals (Sweden)

    Bettina Fussbroich

    Full Text Available The Enhancer of Zeste 2 (EZH2 protein has been reported to stimulate cell growth in some cancers and is therefore considered to represent an interesting new target for therapeutic intervention. Here, we investigated a possible role of EZH2 for the growth control of colon cancer cells. RNA interference (RNAi-mediated intracellular EZH2 depletion led to cell cycle arrest of colon carcinoma cells at the G1/S transition. This was associated with a reduction of cell numbers upon transient transfection of synthetic EZH2-targeting siRNAs and with inhibition of their colony formation capacity upon stable expression of vector-borne siRNAs. We furthermore tested whether EZH2 may repress the growth-inhibitory p27 gene, as reported for pancreatic cancer. However, expression analyses of colon cancer cell lines and colon cancer biopsies did not reveal a consistent correlation between EZH2 and p27 levels. Moreover, EZH2 depletion did not re-induce p27 expression in colon cancer cells, indicating that p27 repression by EZH2 may be cell- or tissue-specific. Whole genome transcriptome analyses identified cellular genes affected by EZH2 depletion in colon cancer cell lines. They included several cancer-associated genes linked to cellular proliferation or invasion, such as Dag1, MageD1, SDC1, Timp2, and Tob1. In conclusion, our results demonstrate that EZH2 depletion blocks the growth of colon cancer cells. These findings might provide benefits for the treatment of colon cancer.

  4. Signaling pathways involved in PDGF-evoked cellular responses in human RPE cells

    International Nuclear Information System (INIS)

    We examined whether PDGF may directly stimulate the expression of VEGF by retinal pigment epithelial (RPE) cells in vitro, and the involvement of three signal transduction pathways in the regulation of PDGF-evoked cell proliferation, migration, and production of VEGF-A was investigated. PDGF stimulated the gene and protein expression of VEGF-A by RPE cells, and increased cell proliferation and chemotaxis. PDGF activated all signaling pathways investigated, as determined by increased phosphorylation levels of ERK1/2, p38, and Akt proteins. The three signaling pathways were involved in the mediation of PDGF-evoked cell proliferation, while p38 and PI3K mediated cell migration, and PI3K mediated secretion of VEGF-A. In addition to VEGF-A, the cells expressed mRNAs for various members of the VEGF family and for their receptors, including VEGF-B, -C, -D, flt-1, and KDR. The data indicate that PDGF selectively stimulates the expression of VEGF-A in RPE cells. PDGF evokes at least three signal transduction pathways which are differentially involved in various cellular responses

  5. RNase-L control of cellular mRNAs: roles in biologic functions and mechanisms of substrate targeting.

    Science.gov (United States)

    Brennan-Laun, Sarah E; Ezelle, Heather J; Li, Xiao-Ling; Hassel, Bret A

    2014-04-01

    RNase-L is a mediator of type 1 interferon-induced antiviral activity that has diverse and critical cellular roles, including the regulation of cell proliferation, differentiation, senescence and apoptosis, tumorigenesis, and the control of the innate immune response. Although RNase-L was originally shown to mediate the endonucleolytic cleavage of both viral and ribosomal RNAs in response to infection, more recent evidence indicates that RNase-L also functions in the regulation of cellular mRNAs as an important mechanism by which it exerts its diverse biological functions. Despite this growing body of work, many questions remain regarding the roles of mRNAs as RNase-L substrates. This review will survey known and putative mRNA substrates of RNase-L, propose mechanisms by which it may selectively cleave these transcripts, and postulate future clinical applications. PMID:24697205

  6. Irregular Cellular Learning Automata.

    Science.gov (United States)

    Esnaashari, Mehdi; Meybodi, Mohammad Reza

    2015-08-01

    Cellular learning automaton (CLA) is a recently introduced model that combines cellular automaton (CA) and learning automaton (LA). The basic idea of CLA is to use LA to adjust the state transition probability of stochastic CA. This model has been used to solve problems in areas such as channel assignment in cellular networks, call admission control, image processing, and very large scale integration placement. In this paper, an extension of CLA called irregular CLA (ICLA) is introduced. This extension is obtained by removing the structure regularity assumption in CLA. Irregularity in the structure of ICLA is needed in some applications, such as computer networks, web mining, and grid computing. The concept of expediency has been introduced for ICLA and then, conditions under which an ICLA becomes expedient are analytically found. PMID:25291810

  7. Architected Cellular Materials

    Science.gov (United States)

    Schaedler, Tobias A.; Carter, William B.

    2016-07-01

    Additive manufacturing enables fabrication of materials with intricate cellular architecture, whereby progress in 3D printing techniques is increasing the possible configurations of voids and solids ad infinitum. Examples are microlattices with graded porosity and truss structures optimized for specific loading conditions. The cellular architecture determines the mechanical properties and density of these materials and can influence a wide range of other properties, e.g., acoustic, thermal, and biological properties. By combining optimized cellular architectures with high-performance metals and ceramics, several lightweight materials that exhibit strength and stiffness previously unachievable at low densities were recently demonstrated. This review introduces the field of architected materials; summarizes the most common fabrication methods, with an emphasis on additive manufacturing; and discusses recent progress in the development of architected materials. The review also discusses important applications, including lightweight structures, energy absorption, metamaterials, thermal management, and bioscaffolds.

  8. Cellular Homeostasis and Aging.

    Science.gov (United States)

    Hartl, F Ulrich

    2016-06-01

    Aging and longevity are controlled by a multiplicity of molecular and cellular signaling events that interface with environmental factors to maintain cellular homeostasis. Modulation of these pathways to extend life span, including insulin-like signaling and the response to dietary restriction, identified the cellular machineries and networks of protein homeostasis (proteostasis) and stress resistance pathways as critical players in the aging process. A decline of proteostasis capacity during aging leads to dysfunction of specific cell types and tissues, rendering the organism susceptible to a range of chronic diseases. This volume of the Annual Review of Biochemistry contains a set of two reviews addressing our current understanding of the molecular mechanisms underlying aging in model organisms and humans. PMID:27050288

  9. Hedgehog pathway regulators influence cervical cancer cell proliferation, survival and migration

    International Nuclear Information System (INIS)

    Highlights: ► Unknown cellular mutations complement papillomavirus-induced carcinogenesis. ► Hedgehog pathway components are expressed by cervical cancer cells. ► Hedgehog pathway activators and inhibitors regulate cervical cancer cell biology. ► Cell immortalization by papillomavirus and activation of Hedgehog are independent. -- Abstract: Human papillomavirus (HPV) infection is considered to be a primary hit that causes cervical cancer. However, infection with this agent, although needed, is not sufficient for a cancer to develop. Additional cellular changes are required to complement the action of HPV, but the precise nature of these changes is not clear. Here, we studied the function of the Hedgehog (Hh) signaling pathway in cervical cancer. The Hh pathway can have a role in a number of cancers, including those of liver, lung and digestive tract. We found that components of the Hh pathway are expressed in several cervical cancer cell lines, indicating that there could exists an autocrine Hh signaling loop in these cells. Inhibition of Hh signaling reduces proliferation and survival of the cervical cancer cells and induces their apoptosis as seen by the up-regulation of the pro-apoptotic protein cleaved caspase 3. Our results indicate that Hh signaling is not induced directly by HPV-encoded proteins but rather that Hh-activating mutations are selected in cells initially immortalized by HPV. Sonic Hedgehog (Shh) ligand induces proliferation and promotes migration of the cervical cancer cells studied. Together, these results indicate pro-survival and protective roles of an activated Hh signaling pathway in cervical cancer-derived cells, and suggest that inhibition of this pathway may be a therapeutic option in fighting cervical cancer.

  10. Hedgehog pathway regulators influence cervical cancer cell proliferation, survival and migration

    Energy Technology Data Exchange (ETDEWEB)

    Samarzija, Ivana [Ecole Polytechnique Federale Lausanne (EPFL), Department of Life Sciences, Swiss Institute for Experimental Cancer Research (ISREC), 1015 Lausanne (Switzerland); Beard, Peter, E-mail: peter.beard@epfl.ch [Ecole Polytechnique Federale Lausanne (EPFL), Department of Life Sciences, Swiss Institute for Experimental Cancer Research (ISREC), 1015 Lausanne (Switzerland)

    2012-08-17

    Highlights: Black-Right-Pointing-Pointer Unknown cellular mutations complement papillomavirus-induced carcinogenesis. Black-Right-Pointing-Pointer Hedgehog pathway components are expressed by cervical cancer cells. Black-Right-Pointing-Pointer Hedgehog pathway activators and inhibitors regulate cervical cancer cell biology. Black-Right-Pointing-Pointer Cell immortalization by papillomavirus and activation of Hedgehog are independent. -- Abstract: Human papillomavirus (HPV) infection is considered to be a primary hit that causes cervical cancer. However, infection with this agent, although needed, is not sufficient for a cancer to develop. Additional cellular changes are required to complement the action of HPV, but the precise nature of these changes is not clear. Here, we studied the function of the Hedgehog (Hh) signaling pathway in cervical cancer. The Hh pathway can have a role in a number of cancers, including those of liver, lung and digestive tract. We found that components of the Hh pathway are expressed in several cervical cancer cell lines, indicating that there could exists an autocrine Hh signaling loop in these cells. Inhibition of Hh signaling reduces proliferation and survival of the cervical cancer cells and induces their apoptosis as seen by the up-regulation of the pro-apoptotic protein cleaved caspase 3. Our results indicate that Hh signaling is not induced directly by HPV-encoded proteins but rather that Hh-activating mutations are selected in cells initially immortalized by HPV. Sonic Hedgehog (Shh) ligand induces proliferation and promotes migration of the cervical cancer cells studied. Together, these results indicate pro-survival and protective roles of an activated Hh signaling pathway in cervical cancer-derived cells, and suggest that inhibition of this pathway may be a therapeutic option in fighting cervical cancer.

  11. Uncertainties in Nuclear Proliferation Modeling

    International Nuclear Information System (INIS)

    There have been various efforts in the research community to understand the determinants of nuclear proliferation and develop quantitative tools to predict nuclear proliferation events. Such systematic approaches have shown the possibility to provide warning for the international community to prevent nuclear proliferation activities. However, there are still large debates for the robustness of the actual effect of determinants and projection results. Some studies have shown that several factors can cause uncertainties in previous quantitative nuclear proliferation modeling works. This paper analyzes the uncertainties in the past approaches and suggests future works in the view of proliferation history, analysis methods, and variable selection. The research community still lacks the knowledge for the source of uncertainty in current models. Fundamental problems in modeling will remain even other advanced modeling method is developed. Before starting to develop fancy model based on the time dependent proliferation determinants' hypothesis, using graph theory, etc., it is important to analyze the uncertainty of current model to solve the fundamental problems of nuclear proliferation modeling. The uncertainty from different proliferation history coding is small. Serious problems are from limited analysis methods and correlation among the variables. Problems in regression analysis and survival analysis cause huge uncertainties when using the same dataset, which decreases the robustness of the result. Inaccurate variables for nuclear proliferation also increase the uncertainty. To overcome these problems, further quantitative research should focus on analyzing the knowledge suggested on the qualitative nuclear proliferation studies

  12. Proliferation: myth or reality?; La proliferation: mythe ou realite?

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-07-01

    This article analyzes the proliferation approach, its technical condition and political motivation, and the share between the myth (political deception, assumptions and extrapolations) and the reality of proliferation. Its appreciation is complicated by the irrational behaviour of some political actors and by the significant loss of the non-use taboo. The control of technologies is an important element for proliferation slowing down but an efficient and autonomous intelligence system remains indispensable. (J.S.)

  13. Cellular functions of p53 and p53 gene family members p63 and p73

    OpenAIRE

    Nadir Koçak; İbrahim Halil Yıldırım; Seval Cing Yıldırım

    2011-01-01

    p53 is a transcription factor that regulates multiple cellular processes that are also important in cellular fates such as cell cycle arrest or programmed cell death. Induction of growth arrest or cell death by p53 prevents the replication of damaged DNA and proliferation of genetically abnormal cells. Therefore, inactivation of p53 by mutation or deletion is also important in ensuring the cellular homeostasis. However, studies showed that p53 deficient mice and cells such as Saos-2 cells are...

  14. Economics of WiFi Offloading: Trading Delay for Cellular Capacity

    OpenAIRE

    Lee, Joohyun; Yi, Yung; Chong, Song; Jin, Youngmi

    2012-01-01

    Cellular networks are facing severe traffic overloads due to the proliferation of smart handheld devices and traffic-hungry applications. A cost-effective and practical solution is to offload cellular data through WiFi. Recent theoretical and experimental studies show that a scheme, referred to as delayed WiFi offloading, can significantly save the cellular capacity by delaying users' data and exploiting mobility and thus increasing chance of meeting WiFi APs (Access Points). Despite a huge p...

  15. Wireless Cellular Mobile Communications

    Directory of Open Access Journals (Sweden)

    V. Zalud

    2002-12-01

    Full Text Available In this article is briefly reviewed the history of wireless cellularmobile communications, examined the progress in current secondgeneration (2G cellular standards and discussed their migration to thethird generation (3G. The European 2G cellular standard GSM and itsevolution phases GPRS and EDGE are described somewhat in detail. Thethird generation standard UMTS taking up on GSM/GPRS core network andequipped with a new advanced access network on the basis of codedivision multiple access (CDMA is investigated too. A sketch of theperspective of mobile communication beyond 3G concludes this article.

  16. Strain variations in the murine cellular immune response to the phenolic glycolipid I antigen of Mycobacterium leprae.

    Science.gov (United States)

    Koster, F T; Teuscher, C; Matzner, P; Umland, E; Yanagihara, D; Brennan, P J; Tung, K S

    1986-01-01

    The cellular immune response to the Mycobacterium leprae-specific phenolic glycolipid I was examined in inbred mice immunized with M. leprae by in vivo delayed cutaneous hypersensitivity and in vitro lymphocyte proliferation. Whereas all mouse strains responded to M.leprae-induced delayed-type hypersensitivity and lymphocyte proliferation, only BALB.K was responsive in both assays to the glycolipid. Responsiveness was determined in part by non-H-2 genes, while the influence of H-2 genes was not apparent. Among congenic BALB/c mice differing only at Igh-C allotype loci, variations in responsiveness were found in both delayed-type hypersensitivity and lymphocytes proliferation assays, indicating a possible role for Igh-C loci-linked genes. Unresponsiveness in the lymphocyte proliferation assay to the glycolipid was inherited as a dominant trait in one set of responder X nonresponder F1 progeny. We conclude that after immunization with M. leprae organisms, the cell-mediated responses to the glycolipid, endowed with a single carbohydrate epitope, are under polygenic control, predominantly non-H-2-linked genes. PMID:3510979

  17. Operational indicators

    International Nuclear Information System (INIS)

    The chapter presents the operational indicators related to budget, travel costs and tickets, the evolution of the annual program for regulatory inspection, the scientific production, requested patents and the numbers related to the production of the services offered by the Institution

  18. Translating partitioned cellular automata into classical type cellular automata

    OpenAIRE

    Poupet, Victor

    2008-01-01

    Partitioned cellular automata are a variant of cellular automata that was defined in order to make it very simple to create complex automata having strong properties such as number conservation and reversibility (which are often difficult to obtain on cellular automata). In this article we show how a partitioned cellular automaton can be translated into a regular cellular automaton in such a way that these properties are conserved.

  19. Reversible effect of all-trans-retinoic acid on AML12 hepatocyte proliferation and cell cycle progression

    Science.gov (United States)

    The role of all-trans-retinoic acid (atRA) in the regulation of cellular proliferation and differentiation is well documented. Numerous studies have established the cancer preventive propertiesofatRAwhichfunctionstoregulate levels ofcellcycleproteinsessentialfortheGliS transition...

  20. The changing proliferation threat

    Energy Technology Data Exchange (ETDEWEB)

    Sopko, J.F.

    1996-12-31

    Technological advances and new adversaries with new motives have reduced the relevancy and effectiveness of the American nonproliferation strategy that was developed during the Cold War. The Cold War`s end and the breakup of the Soviet Union have created new proliferation dangers even as they have reduced others. The familiar balance of nuclear terror that linked the superpowers and their client states for nearly 50 years in a choreographed series of confrontations has given way to a much less predictable situation, where weapons of unthinkable power appear within the grasp of those more willing to use them. Rogue nations and {open_quotes}clientless{close_quotes} states, terrorist groups, religious cults, ethnic minorities, disaffected political groups, and even individuals appear to have jointed a new arms race toward mass destruction. The author describes recent events that suggest the new trends and a serious challenge to US national security.

  1. Genetic Dominance & Cellular Processes

    Science.gov (United States)

    Seager, Robert D.

    2014-01-01

    In learning genetics, many students misunderstand and misinterpret what "dominance" means. Understanding is easier if students realize that dominance is not a mechanism, but rather a consequence of underlying cellular processes. For example, metabolic pathways are often little affected by changes in enzyme concentration. This means that…

  2. Radioactivity of cellular concrete

    International Nuclear Information System (INIS)

    The natural radioactivity of cellular concrete is discussed. Some data on the concentrations of 40K, 226Ra and 232Th in building materials in Poland are given. The results of dose rates measurements in living quarters as well as outside are presented. (A.S.)

  3. The New Cellular Immunology

    Science.gov (United States)

    Claman, Henry N.

    1973-01-01

    Discusses the nature of the immune response and traces many of the discoveries that have led to the present state of knowledge in immunology. The new cellular immunology is directing its efforts toward improving health by proper manipulation of the immune mechanisms of the body. (JR)

  4. Factors influencing ER subtype-mediated cell proliferation and apoptosis

    OpenAIRE

    Evers, N.M.

    2014-01-01

      The aim of the current thesis is to elucidate the role of estrogen receptor (ER)αand ERβin cell proliferation and apoptosis induced by estrogenic compounds. Special attention is paid to the importance of the receptor preference of the estrogenic compounds, the cellular ERα/ERβratio, the role of coregulators, and ER-mediated induction of protein expression. In chapter 1 estrogenic compounds and their interaction with estrogen receptors are described and the two dif...

  5. Roles of Nrf2 in cell proliferation and differentiation.

    Science.gov (United States)

    Murakami, Shohei; Motohashi, Hozumi

    2015-11-01

    The Keap1-Nrf2 system plays pivotal roles in defense mechanisms by regulating cellular redox homeostasis. Nrf2 is an inducible transcription factor that activates a battery of genes encoding antioxidant proteins and phase II enzymes in response to oxidative stress and electrophilic xenobiotics. The activity of Nrf2 is regulated by Keap1, which promotes the ubiquitination and subsequent degradation of Nrf2 under normal conditions and releases the inhibited Nrf2 activity upon exposure to the stresses. Though an impressive contribution of the Keap1-Nrf2 system to the protection from exogenous and endogenous electrophilic insults has been well established, a line of evidence has suggested that the Keap1-Nrf2 system has various novel functions, particularly in cell proliferation and differentiation. Because the proliferation and differentiation of diverse cell types are often influenced and modulated by the cellular redox balance, Nrf2 has been considered to control these cellular processes by regulating the cellular levels of reactive oxygen species (ROS). In addition, analyses of the genome-wide distribution of Nrf2 have identified new sets of Nrf2 target genes whose products are involved in cell proliferation and differentiation but not necessarily in the regulation of oxidative stress. Considering the most characteristic features of Nrf2 as an inducible transcription factor, a newly emerged concept proposes that the Keap1-Nrf2 system translates environmental stresses into regulatory network signals in cell fate determination. In this review, we introduce the contribution of Nrf2 to lineage-specific differentiation, maintenance and differentiation of stem cells, and proliferation of normal and cancer cells, and we discuss how the response to fluctuating environments modulates cell behavior through the Keap1-Nrf2 system. PMID:26119783

  6. An Integrative Genomic and Transcriptomic Analysis Reveals Potential Targets Associated with Cell Proliferation in Uterine Leiomyomas

    Science.gov (United States)

    Cirilo, Priscila Daniele Ramos; Marchi, Fábio Albuquerque; Barros Filho, Mateus de Camargo; Rocha, Rafael Malagoli; Domingues, Maria Aparecida Custódio; Jurisica, Igor; Pontes, Anagloria; Rogatto, Silvia Regina

    2013-01-01

    Background Uterine Leiomyomas (ULs) are the most common benign tumours affecting women of reproductive age. ULs represent a major problem in public health, as they are the main indication for hysterectomy. Approximately 40–50% of ULs have non-random cytogenetic abnormalities, and half of ULs may have copy number alterations (CNAs). Gene expression microarrays studies have demonstrated that cell proliferation genes act in response to growth factors and steroids. However, only a few genes mapping to CNAs regions were found to be associated with ULs. Methodology We applied an integrative analysis using genomic and transcriptomic data to identify the pathways and molecular markers associated with ULs. Fifty-one fresh frozen specimens were evaluated by array CGH (JISTIC) and gene expression microarrays (SAM). The CONEXIC algorithm was applied to integrate the data. Principal Findings The integrated analysis identified the top 30 significant genes (PTranscriptional and protein analyses showed that FGFR1 (P = 0.006 and P<0.01, respectively) and IGFBP5 (P = 0.0002 and P = 0.006, respectively) were up-regulated in the tumours when compared with the adjacent normal myometrium. Conclusions The integrative genomic and transcriptomic approach indicated that FGFR1 and IGFBP5 amplification, as well as the consequent up-regulation of the protein products, plays an important role in the aetiology of ULs and thus provides data for potential drug therapies development to target genes associated with cellular proliferation in ULs. PMID:23483937

  7. High VRK1 expression contributes to cell proliferation and survival in hepatocellular carcinoma.

    Science.gov (United States)

    Huang, Wei; Cui, Xiaopeng; Chen, Yuyan; Shao, Mengting; Shao, Xian; Shen, Yifen; Liu, Qingqing; Wu, Miaomiao; Liu, Jinxia; Ni, Wenkai; Lu, Cuihua; Wan, Chunhua

    2016-03-01

    VRK1 is a member of the vaccinia-related kinase (VRK) family of serine/threonine protein kinases, which is known to play multiple roles in cellular proliferation, cell cycle regulation and carcinogenesis. However, the expression and physiological significance of VRK1 in hepatocellular carcinoma (HCC) remain unclear. In this study, we aimed to investigate the potential role of VRK1 in the development and progression of HCC. Western blot and immunohistochemical analysis revealed that VRK1 was highly expressed in HCC tissues and cell lines, compared with adjacent nontumorous tissues and LO2 normal hepatocytes. Meanwhile, clinicopathological analysis showed that VRK1 was significantly associated with AJCC stage, Ki-67 and a poor prognosis in HCC specimens. Univariate and multivariate analysis showed that VRK1 could serve as an independent prognostic indicator of HCC patients' survival. Furthermore, we found that VRK1 was lowly expressed in serum-starved Huh7 cells, and was progressively increased after serum-refeeding. Finally, flow cytometry, CCK-8 and colony formation assay indicated that the depletion of VRK1 could retard cell cycle progression and reduce cells proliferation in HCC cells. On the basis of these findings, we conclude that VRK1 may be a candidate prognostic biomarker as well as a potential therapeutical target of HCC. PMID:26706601

  8. Measuring corruption indicators and indices

    OpenAIRE

    MALITO, Debora Valentina

    2014-01-01

    This Working Paper is a background paper delivered to frame the workshop ‘Global Governance by Indicators: Measuring corruption and corruption indicators’ convened by the Global Governance Programme of the European University Institute in Florence on 17 and 18 October 2013. Successively it was developed further in EUI RSCAS WP 2014/37 - http://hdl.handle.net/1814/30582

  9. Soluble β-glucan from Grifola frondosa induces proliferation and Dectin-1/Syk signaling in resident macrophages via the GM-CSF autocrine pathway.

    Science.gov (United States)

    Masuda, Yuki; Togo, Takuya; Mizuno, Shigeto; Konishi, Morichika; Nanba, Hiroaki

    2012-04-01

    MD-Fraction, a highly purified, soluble β-(1,3) (1,6)-glucan obtained from Grifola frondosa (an oriental edible mushroom), has been reported to inhibit tumor growth by modulating host immunity. β-Glucan, a major component of the fungal cell wall, is generally recognized by PRRs expressed on macrophages and DCs, such as Dectin-1, and the ability of β-glucans to modulate host immunity is influenced by their structure and purity. Most cellular studies have used particulate β-glucans, such as yeast zymosan (crude β-glucan) and curdlan (purified β-glucan). However, little is known about the cellular mechanism of soluble β-glucans, including MD-Fraction, despite significant therapeutic implications. In this study, we investigated the cellular mechanism of MD-Fraction in murine resident macrophages and compared it with two well-known β-glucan particles. MD-Fraction induced GM-CSF production rapidly through Dectin-1-independent ERK and p38 MAPK activation. Subsequently, MD-Fraction-induced GM-CSF enhanced proliferation and Dectin-1 expression, which permitted Dectin-1-mediated TNF-α induction through the Syk pathway. Curdlan induced not only the proliferation and activation of Dectin-1/Syk signaling in a manner similar to MD-Fraction but also the uncontrolled, proinflammatory cytokine response. Contrastingly, zymosan reduced proliferation and Dectin-1 expression significantly, indicating that the mechanism of macrophage activation by MD-Fraction differs from that of zymosan. This is the first study to demonstrate that purified β-glucans, such as MD-Fraction and curdlan, induce GM-CSF production directly, resulting in Dectin-1/Syk activation in resident macrophages. In conclusion, we demonstrated that MD-Fraction induces cell proliferation and cytokine production without excessive inflammation in resident macrophages, supporting its immunotherapeutic potential. PMID:22028332

  10. Aspirin-induced AMP-activated protein kinase activation regulates the proliferation of vascular smooth muscle cells from spontaneously hypertensive rats

    Energy Technology Data Exchange (ETDEWEB)

    Sung, Jin Young [Department of Pharmacology, College of Medicine, Yeungnam University, Daegu 705-717 (Korea, Republic of); Choi, Hyoung Chul, E-mail: hcchoi@med.yu.ac.kr [Department of Pharmacology, College of Medicine, Yeungnam University, Daegu 705-717 (Korea, Republic of)

    2011-05-06

    Highlights: {yields} Aspirin-induced AMPK phosphorylation was greater in VSMC from SHR than WKY. {yields} Aspirin-induced AMPK phosphorylation inhibited proliferation of VSMC from SHR. {yields} Low basal AMPK phosphorylation in SHR elicits increased VSMC proliferation. {yields} Inhibition of AMPK restored decreased VSMC proliferation by aspirin in SHR. {yields} Aspirin exerts anti-proliferative effect through AMPK activation in VSMC from SHR. -- Abstract: Acetylsalicylic acid (aspirin), used to reduce risk of cardiovascular disease, plays an important role in the regulation of cellular proliferation. However, mechanisms responsible for aspirin-induced growth inhibition are not fully understood. Here, we investigated whether aspirin may exert therapeutic effects via AMP-activated protein kinase (AMPK) activation in vascular smooth muscle cells (VSMC) from wistar kyoto rats (WKY) and spontaneously hypertensive rats (SHR). Aspirin increased AMPK and acetyl-CoA carboxylase phosphorylation in a time- and dose-dependent manner in VSMCs from WKY and SHR, but with greater efficacy in SHR. In SHR, a low basal phosphorylation status of AMPK resulted in increased VSMC proliferation and aspirin-induced AMPK phosphorylation inhibited proliferation of VSMCs. Compound C, an AMPK inhibitor, and AMPK siRNA reduced the aspirin-mediated inhibition of VSMC proliferation, this effect was more pronounced in SHR than in WKY. In VSMCs from SHR, aspirin increased p53 and p21 expression and inhibited the expression of cell cycle associated proteins, such as p-Rb, cyclin D, and cyclin E. These results indicate that in SHR VSMCs aspirin exerts anti-proliferative effects through the induction of AMPK phosphorylation.

  11. Nuclear Society and non-proliferation problems

    International Nuclear Information System (INIS)

    In the USSR Nuclear Society in 1991 the special working group on the problems of nuclear weapons non-proliferation and nuclear materials control, uniting the experts of different types (nuclear physicists, lawyers, teachers), was created. This group became the mechanism of the practical Nuclear Society activity realization in this sphere. Three milestones of the innovative activity can be specified. First Milestone. In January 1992 the Central Nuclear Society Board (of the International Public Nuclear Society Association) published a special appeal to the First Leaders of all countries - former USSR republics. This address paid a special attention to the unity of the USSR power-industrial complex, and numerous problems arisen while separating this complex, including nuclear weapons non-proliferation problems, were indicated as well. Second Milestone. In 1992 and 1993 the Nuclear Society experts issued two selection 'Nuclear Non-proliferation and Control Problems' including reviewing basic papers. In addition, materials on non-proliferation and control are published regularly in the organs. Third Milestone.In 1993 - 1997 some special scientific and technical events (conferences, workshops, meetings) allowing to analyze the joint international projects and contracts outcomes, and establish new contacts between the specialists of NIS, Baltic states and others, have been hold

  12. The involvement of XPC protein in the cisplatin DNA damaging treatment-mediated cellular response

    Institute of Scientific and Technical Information of China (English)

    Gan WANG; Alan DOMBKOWSKI; Lynn CHUANG; Xiao Xin S XU

    2004-01-01

    Recognition of DNA damage is a critical step for DNA damage-mediated cellular response. XPC is an important DNA damage recognition protein involved in nucleotide excision repair (NER). We have studied the XPC protein in cisplatin DNA damaging treatment-mediated cellular response. Comparison of the microarray data from both normal and XPCdefective human fibroblasts identified 861 XPC-responsive genes in the cisplatin treatment (with minimum fold change≥1.5).The cell cycle and cell proliferation-related genes are the most affected genes by the XPC defect in the treatment. Many other cellular function genes, especially the DNA repair and signal transduction-related genes, were also affected by the XPC defect in the treatment. To validate the microarray data, the transcription levels of some microarray-identified genes were also determined by an RT-PCR based real time PCR assay. The real time PCR results are consistent with the microarray data for most of the tested genes, indicating the reliability of the microarray data. To further validate the microarray data, the cisplatin treatment-mediated caspase-3 activation was also determined. The Western blot hybridization results indicate that the XPC defect greatly attenuates the cisplatin treatment-mediated Caspase-3 activation. We elucidated the role of p53 protein in the XPC protein DNA damage recognition-mediated signaling process. The XPC defect reduces the cisplatin treatment-mediated p53 response. These results suggest that the XPC protein plays an important role in the cisplatin treatment-mediated cellular response. It may also suggest a possible mechanism of cancer cell drug resistance.

  13. Cellularized Bilayer Pullulan-Gelatin Hydrogel for Skin Regeneration.

    Science.gov (United States)

    Nicholas, Mathew N; Jeschke, Marc G; Amini-Nik, Saeid

    2016-05-01

    Skin substitutes significantly reduce the morbidity and mortality of patients with burn injuries and chronic wounds. However, current skin substitutes have disadvantages related to high costs and inadequate skin regeneration due to highly inflammatory wounds. Thus, new skin substitutes are needed. By combining two polymers, pullulan, an inexpensive polysaccharide with antioxidant properties, and gelatin, a derivative of collagen with high water absorbency, we created a novel inexpensive hydrogel-named PG-1 for "pullulan-gelatin first generation hydrogel"-suitable for skin substitutes. After incorporating human fibroblasts and keratinocytes onto PG-1 using centrifugation over 5 days, we created a cellularized bilayer skin substitute. Cellularized PG-1 was compared to acellular PG-1 and no hydrogel (control) in vivo in a mouse excisional skin biopsy model using newly developed dome inserts to house the skin substitutes and prevent mouse skin contraction during wound healing. PG-1 had an average pore size of 61.69 μm with an ideal elastic modulus, swelling behavior, and biodegradability for use as a hydrogel for skin substitutes. Excellent skin cell viability, proliferation, differentiation, and morphology were visualized through live/dead assays, 5-bromo-2'-deoxyuridine proliferation assays, and confocal microscopy. Trichrome and immunohistochemical staining of excisional wounds treated with the cellularized skin substitute revealed thicker newly formed skin with a higher proportion of actively proliferating cells and incorporation of human cells compared to acellular PG-1 or control. Excisional wounds treated with acellular or cellularized hydrogels showed significantly less macrophage infiltration and increased angiogenesis 14 days post skin biopsy compared to control. These results show that PG-1 has ideal mechanical characteristics and allows ideal cellular characteristics. In vivo evidence suggests that cellularized PG-1 promotes skin regeneration and may

  14. Spin Echo Studies on Cellular Water

    CERN Document Server

    Chang, D C; Nichols, B L; Rorschach, H E

    2014-01-01

    Previous studies indicated that the physical state of cellular water could be significantly different from pure liquid water. To experimentally investigate this possibility, we conducted a series of spin-echo NMR measurements on water protons in rat skeletal muscle. Our result indicated that the spin-lattice relaxation time and the spin-spin relaxation time of cellular water protons are both significantly shorter than that of pure water (by 4.3-fold and 34-fold, respectively). Furthermore, the spin diffusion coefficient of water proton is almost 1/2 of that of pure water. These data suggest that cellular water is in a more ordered state in comparison to pure water.

  15. HDACi: cellular effects, opportunities for restorative dentistry.

    LENUS (Irish Health Repository)

    Duncan, H F

    2011-12-01

    Acetylation of histone and non-histone proteins alters gene expression and induces a host of cellular effects. The acetylation process is homeostatically balanced by two groups of cellular enzymes, histone acetyltransferases (HATs) and histone deacetylases (HDACs). HAT activity relaxes the structure of the human chromatin, rendering it transcriptionally active, thereby increasing gene expression. In contrast, HDAC activity leads to gene silencing. The enzymatic balance can be \\'tipped\\' by histone deacetylase inhibitors (HDACi), leading to an accumulation of acetylated proteins, which subsequently modify cellular processes including stem cell differentiation, cell cycle, apoptosis, gene expression, and angiogenesis. There is a variety of natural and synthetic HDACi available, and their pleiotropic effects have contributed to diverse clinical applications, not only in cancer but also in non-cancer areas, such as chronic inflammatory disease, bone engineering, and neurodegenerative disease. Indeed, it appears that HDACi-modulated effects may differ between \\'normal\\' and transformed cells, particularly with regard to reactive oxygen species accumulation, apoptosis, proliferation, and cell cycle arrest. The potential beneficial effects of HDACi for health, resulting from their ability to regulate global gene expression by epigenetic modification of DNA-associated proteins, also offer potential for application within restorative dentistry, where they may promote dental tissue regeneration following pulpal damage.

  16. Molecular and Cellular Signaling

    CERN Document Server

    Beckerman, Martin

    2005-01-01

    A small number of signaling pathways, no more than a dozen or so, form a control layer that is responsible for all signaling in and between cells of the human body. The signaling proteins belonging to the control layer determine what kinds of cells are made during development and how they function during adult life. Malfunctions in the proteins belonging to the control layer are responsible for a host of human diseases ranging from neurological disorders to cancers. Most drugs target components in the control layer, and difficulties in drug design are intimately related to the architecture of the control layer. Molecular and Cellular Signaling provides an introduction to molecular and cellular signaling in biological systems with an emphasis on the underlying physical principles. The text is aimed at upper-level undergraduates, graduate students and individuals in medicine and pharmacology interested in broadening their understanding of how cells regulate and coordinate their core activities and how diseases ...

  17. Pulsed feedback defers cellular differentiation.

    Directory of Open Access Journals (Sweden)

    Joe H Levine

    2012-01-01

    Full Text Available Environmental signals induce diverse cellular differentiation programs. In certain systems, cells defer differentiation for extended time periods after the signal appears, proliferating through multiple rounds of cell division before committing to a new fate. How can cells set a deferral time much longer than the cell cycle? Here we study Bacillus subtilis cells that respond to sudden nutrient limitation with multiple rounds of growth and division before differentiating into spores. A well-characterized genetic circuit controls the concentration and phosphorylation of the master regulator Spo0A, which rises to a critical concentration to initiate sporulation. However, it remains unclear how this circuit enables cells to defer sporulation for multiple cell cycles. Using quantitative time-lapse fluorescence microscopy of Spo0A dynamics in individual cells, we observed pulses of Spo0A phosphorylation at a characteristic cell cycle phase. Pulse amplitudes grew systematically and cell-autonomously over multiple cell cycles leading up to sporulation. This pulse growth required a key positive feedback loop involving the sporulation kinases, without which the deferral of sporulation became ultrasensitive to kinase expression. Thus, deferral is controlled by a pulsed positive feedback loop in which kinase expression is activated by pulses of Spo0A phosphorylation. This pulsed positive feedback architecture provides a more robust mechanism for setting deferral times than constitutive kinase expression. Finally, using mathematical modeling, we show how pulsing and time delays together enable "polyphasic" positive feedback, in which different parts of a feedback loop are active at different times. Polyphasic feedback can enable more accurate tuning of long deferral times. Together, these results suggest that Bacillus subtilis uses a pulsed positive feedback loop to implement a "timer" that operates over timescales much longer than a cell cycle.

  18. Electromagnetic cellular interactions

    Czech Academy of Sciences Publication Activity Database

    Cifra, Michal; Fields, J. S.; Farhadi, A.

    2011-01-01

    Roč. 105, č. 3 (2011), 223-246. ISSN 0079-6107. [36th International Congress of Physiological Sciences (IUPS2009). Kyoto, 27.07.2009-01.08.2009] R&D Projects: GA ČR(CZ) GPP102/10/P454 Institutional research plan: CEZ:AV0Z20670512 Keywords : bioelectric phenomena * cellular biophysics Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering Impact factor: 3.203, year: 2011

  19. Magnetic Cellular Switches

    OpenAIRE

    Overby, Darryl R.; Alenghat, Francis J.; Montoya-Zavala, Martín; Bei, HuCheng; Oh, Philmo; Karavitis, John; Ingber, Donald E.

    2004-01-01

    This paper focuses on the development of magnetic cellular switches to enable magnetic control of intracellular functions in living mammalian cells, including receptor signal transduction and gene transcription. Our approach takes advantage of the mechanosensitivity of adenosine 3′,5′-monophosphate (cAMP) induction and downstream transcription controlled by the cAMP regulatory element (CRE) to engineer gene constructs that optically report gene expression in living cells. We activate transcri...

  20. Romania non-proliferation policy

    International Nuclear Information System (INIS)

    a component of the National Development Strategy for Romania, presented to the European Union, as a main step in the accession process. Cernavoda NPP Unit 1 is in commercial operation from 1996 and assures 10% of the overall national electricity production. Cernavoda Unit 2 is now about 40% complete, and the Government of Romania has declared its completion as a national priority. The national participation in this project planned to be completed by the year 2005 comprises important contribution of the nuclear infrastructure developed in Romania for the CANDU power plants. Physical Protection of Nuclear Material is also regarded as a fundamental element of the non-proliferation regime. Physical Protection comprises those measures that Romania apply to prevent or deter illegal actions taken against nuclear facilities and nuclear materials, particularly when such materials, are transported across the country. Romania received IAEA assistance to enhance its efforts to prevent unclear material and other radioactive sources from being use illegally and to detect and respond to trafficking cases, should they occur. This assistance included an IPASS Mission and training for staff involved in physical protection for nuclear material and nuclear installations. In 1993 Romania ratified the Convention on Physical Protection of Nuclear Material and has following requirements for nuclear material transport: the material must be classified according to its characteristics, the material may be transported only in approved containers, containers must be marked with safety labels or placards to indicate their contents, for certain radioactive material the shipper must have in place an emergency response assistance plan. CNCAN coordinates at national level the activities regarding preventing and combating illicit trafficking with nuclear materials. From 1993 when the IAEA database was installed, Romania reported 22 incidents involving nuclear material and radioactive sources. In

  1. Cellular therapy in Tuberculosis

    Directory of Open Access Journals (Sweden)

    Shreemanta K. Parida

    2015-03-01

    Full Text Available Cellular therapy now offer promise of potential adjunct therapeutic options for treatment of drug-resistant tuberculosis (TB. We review here the role of Mesenchymal stromal cells, (MSCs, as well as other immune effector cells in the therapy of infectious diseases with a focus on TB. MSCs represent a population of tissue-resident non-hematopoietic adult progenitor cells which home into injured tissues increase the proliferative potential of broncho-alveolar stem cells and restore lung epithelium. MSCs have been shown to be immune-modulatory and anti-inflammatory mediated via cell-cell contacts as well as soluble factors. We discuss the functional profile of MSCs and their potential use for adjunct cellular therapy of multi-drug resistant TB, with the aim of limiting tissue damage, and to convert unproductive inflammatory responses into effective anti-pathogen directed immune responses. Adjunct cellular therapy could potentially offer salvage therapy options for patients with drug-resistant TB, increase clinically relevant anti-M.tuberculosis directed immune responses and possibly shorten the duration of anti-TB therapy.

  2. Cellular therapy in tuberculosis.

    Science.gov (United States)

    Parida, Shreemanta K; Madansein, Rajhmun; Singh, Nalini; Padayatchi, Nesri; Master, Iqbal; Naidu, Kantharuben; Zumla, Alimuddin; Maeurer, Markus

    2015-03-01

    Cellular therapy now offer promise of potential adjunct therapeutic options for treatment of drug-resistant tuberculosis (TB). We review here the role of Mesenchymal stromal cells, (MSCs), as well as other immune effector cells in the therapy of infectious diseases with a focus on TB. MSCs represent a population of tissue-resident non-hematopoietic adult progenitor cells which home into injured tissues increase the proliferative potential of broncho-alveolar stem cells and restore lung epithelium. MSCs have been shown to be immune-modulatory and anti-inflammatory mediated via cell-cell contacts as well as soluble factors. We discuss the functional profile of MSCs and their potential use for adjunct cellular therapy of multi-drug resistant TB, with the aim of limiting tissue damage, and to convert unproductive inflammatory responses into effective anti-pathogen directed immune responses. Adjunct cellular therapy could potentially offer salvage therapy options for patients with drug-resistant TB, increase clinically relevant anti-M.tuberculosis directed immune responses and possibly shorten the duration of anti-TB therapy. PMID:25809753

  3. Quantum cellular automata

    Science.gov (United States)

    Porod, Wolfgang; Lent, Craig S.; Bernstein, Gary H.

    1994-06-01

    The Notre Dame group has developed a new paradigm for ultra-dense and ultra-fast information processing in nanoelectronic systems. These Quantum Cellular Automata (QCA's) are the first concrete proposal for a technology based on arrays of coupled quantum dots. The basic building block of these cellular arrays is the Notre Dame Logic Cell, as it has been called in the literature. The phenomenon of Coulomb exclusion, which is a synergistic interplay of quantum confinement and Coulomb interaction, leads to a bistable behavior of each cell which makes possible their use in large-scale cellular arrays. The physical interaction between neighboring cells has been exploited to implement logic functions. New functionality may be achieved in this fashion, and the Notre Dame group invented a versatile majority logic gate. In a series of papers, the feasibility of QCA wires, wire crossing, inverters, and Boolean logic gates was demonstrated. A major finding is that all logic functions may be integrated in a hierarchial fashion which allows the design of complicated QCA structures. The most complicated system which was simulated to date is a one-bit full adder consisting of some 200 cells. In addition to exploring these new concepts, efforts are under way to physically realize such structures both in semiconductor and metal systems. Extensive modeling work of semiconductor quantum dot structures has helped identify optimum design parameters for QCA experimental implementations.

  4. Nuclear proliferation: linkages and solutions

    International Nuclear Information System (INIS)

    Nuclear proliferation must be periodically re-examined as a moral as well as a practical foreign policy dilemma. The question is asked whether proliferation precludes a safe and peaceful world, or if a halt to proliferation is adequate without other arms control. The moral dilemma in foreign policy arises over the need to make practical choices which often serve one goal while sacrificing another. The ramifications of nuclear proliferation are examined and the conclusions reached that it is not an acceptable option. It is also decided that, because general disarmament steps will be more difficult to achieve, the world may have to accept a small number of nuclear arsenals as the price of state sovereignties. A high priority for making the effort to prevent proliferation is advised. 8 references

  5. THE COMBINED EFFECTS OF CATECHINS AND CAFFEINE ON CELLULAR PROLIFERATION AND LIPID METABOLISM IN 3T3-L1 CELLS%儿茶素和咖啡碱组合对3T3-L1细胞增殖及脂肪代谢的影响

    Institute of Scientific and Technical Information of China (English)

    郑国栋; 邱阳阳; 张清峰; 徐峰

    2013-01-01

    目的 研究对儿茶素和咖啡碱对3T3-L1细胞的增殖及脂肪代谢的影响.方法 采用四甲基偶氮唑盐比色法(MTT)检测对3T3-L1细胞增殖的影响;3T3-L1细胞诱导分化8d后,对各组细胞进行油红O染色并测定细胞内甘油三酯(TG)含量;细胞分化12d后,添加儿茶素和咖啡碱组合或同时添加去甲肾上腺素(NA)作用24h,分析各组细胞内脂肪分解.结果 儿茶素能明显抑制3T3-L1细胞的增殖;儿茶素和咖啡碱组合能明显抑制3T3-L1细胞分化后,细胞内TG的沉积,且在相同儿茶素浓度下,咖啡碱浓度越高抑制效果越明显.咖啡碱明显提高NA诱导成熟脂肪细胞脂解的能力,且呈剂量效应关系.结论 儿茶素和咖啡碱组合能够抑制脂肪细胞增殖和甘油三酯积聚,咖啡碱促进激素诱导脂肪细胞中脂肪分解.%Objective To investigate the combined effects of catechins and caffeine on cells proliferation and lipid metabolism in 3T3-L1 cells. Method MTT colorimetry was used to detect the effects of catechins and caffeine combination on the proliferation of 3T3-L1 cells. The differentiation of 3T3-L1 cells was induced for 8 d, then the adipocytes were stained by oil Red O, and the level of triglyceride (TG) was measured. The lipolytic effect of catechins and caffeine combination in presence or absence of noradrenaline (NA) for 24 h on 3T3-L1 cells was analyzed on the 12 th day after differentiation. Results Catechins significantly inhibited 3T3-L1 cells proliferation. Catechins and caffeine combination remarkably decreased TG accumulation after differentiation of 3T3-L1 cells, and the higher caffeine concentration was better when combined with the same catechins dose. Caffeine significantly improved NA-induced lipolysis in mature adipocytes. Conclusion Catechins and caffeine combination might inhibit cells proliferation and TG accumulation in 3T3-L1 cells. Caffeine promotes hormone-induced lipolysis in adipocytes.

  6. Gadd45a, a p53- and BRCA1-regulated stress protein, in cellular response to DNA damage

    International Nuclear Information System (INIS)

    Mammalian cells exhibit complex, but intricate cellular responses to genotoxic stress, including cell cycle checkpoints, DNA repair and apoptosis. Inactivation of these important biological events may result in genomic instability and cell transformation, as well as alterations of therapeutic sensitivity. Gadd45a, a p53- and BRCA1-regulated stress-inducible gene, has been characterized as one of the important players that participate in cellular response to a variety of DNA damage agents. Interestingly, the signaling machinery that regulates Gadd45a induction by genotoxic stress involves both p53-dependent and -independent pathways; the later may employ BRCA1-related or MAP kinase-mediated signals. Gadd45a protein has been reported to interact with multiple important cellular proteins, including Cdc2 protein kinase, proliferating cell nuclear antigen (PCNA), p21Waf1/Cip1 protein, core histone protein and MTK/MEKK4, an up-stream activator of the JNK/SAPK pathway, indicating that Gadd45a may play important roles in the control of cell cycle checkpoint, DNA repair process, and signaling transduction. The importance of Gadd45a in maintaining genomic integrity is well manifested by the demonstration that disruption of endogenous Gadd45a in mice results in genomic instability and increased carcinogenesis. Therefore, Gadd45a appears to be an important component in the cellular defense network that is required for maintenance of genomic stability

  7. Pathological study of breast cancer by method postneaadyuvancia RCB (residual tumor burden) associated with cell proliferation index report preliminary data

    International Nuclear Information System (INIS)

    Full text: Introduction: The evaluation of residual disease increases prognostic information postneaadyuvancia and obtained by the study of pathological response. Using method index residual tumor burden (RCB)developed at M D Anderson where from morphological parameters (Size of the tumor bed, residual percentage of invasive carcinoma, carcinoma in situ percentage residual metastatic nodes number and size of largest metastasis)the index is calculated. Proliferation index represents an independent predictor of response to particular drugs. A high rate of cell proliferation after chemotherapy is linked with a poor survival We compared the results of both indices Material and Methods: We applied method residual tumor burden index (RCB)in 30 patients operated breast carcinoma after neoadjuvant therapy. Documentation was performed digital macroscopic bed residual tumor, printing and bulk sampling mapping performed on serially reading sheets histological double-blind by two pathologists using graphical illustrations of the percentage of cellularity neoplastic. The application of the formula classified as: RCB 0, complete pathological response (Rpc), RCB I, minimal residual disease, moderate residual disease RCB II, III RBC extensive disease residual. We immunohistochemical proliferation index (PI)with K i 67 in 14 cases (RCB II and III) with double-blinded histological evaluation by performing a percentage of stained nuclei in the greater staining sector thereof and with a cutoff of 14% of stained nuclei. Results: The size of the residual tumor bed was between 4x3mm and 110x60mm. Percentages cellularity invasive component between 0 and 86%, carcinoma in situ between 0 and 30 %. RCB case 0, RCB I a case, RCB RCB II and III seventeen cases eleven cases. Proliferation index was between 1% to 90 %, greater than 14 % in 29% of III and 21% RCB RCB II. Less than 14% was seen in 29% of RCB II and 7% RCB III In six cases there was variation in the rate of pre and post neoadjuvant

  8. Effects of tiflucarbine as a dual protein kinase C/calmodulin antagonist on proliferation of human keratinocytes and release of reactive oxygen species from human leukocytes.

    Science.gov (United States)

    Hegemann, L; Fruchtmann, R; Bonnekoh, B; Schmidt, B H; Traber, J; Mahrle, G; Müller-Peddinghaus, R; van Rooijen, L A

    1991-01-01

    Various studies have suggested that calmodulin (CaM) is involved in the pathophysiology of psoriasis. Protein kinase C (PKC) is also accepted as playing a regulatory role in cell proliferation as well as in inflammatory processes. Therefore, we investigated the effects of the known CaM antagonist tiflucarbine (BAY/TVX P 4495) on two cellular systems related to the major clinical symptoms of psoriasis: proliferation of cultured human keratinocytes (HaCa T cell line) and release of reactive oxygen species (ROS) from human polymorphonuclear leukocytes (PMNL). Tiflucarbine inhibited both cellular responses in a dose dependent manner. Furthermore, tiflucarbine directly affected PKC, and may thus be considered to be a dual PKC/CaM antagonist with putative antipsoriatic activity. The effects of tiflucarbine on the different parameters were compared with those of the structurally unrelated dual PKC/CaM inhibitor W-7 and those of the potent PKC inhibitor staurosporine. The potencies of all three compounds were found to be in the same range as their PKC-inhibiting potency. Our data indicate that PKC, rather than CaM, may play a regulatory role in the release of ROS as well as in keratinocyte proliferation. Therefore, inhibition of PKC in general might have a therapeutic benefit in psoriasis. PMID:1801655

  9. DNA-damage response network at the crossroads of cell-cycle checkpoints, cellular senescence and apoptosis*

    OpenAIRE

    Schmitt, Estelle; Paquet, Claudie; Beauchemin, Myriam; Bertrand, Richard

    2007-01-01

    Tissue homeostasis requires a carefully-orchestrated balance between cell proliferation, cellular senescence and cell death. Cells proliferate through a cell cycle that is tightly regulated by cyclin-dependent kinase activities. Cellular senescence is a safeguard program limiting the proliferative competence of cells in living organisms. Apoptosis eliminates unwanted cells by the coordinated activity of gene products that regulate and effect cell death. The intimate link between the cell cycl...

  10. Environment Aware Cellular Networks

    KAUST Repository

    Ghazzai, Hakim

    2015-02-01

    The unprecedented rise of mobile user demand over the years have led to an enormous growth of the energy consumption of wireless networks as well as the greenhouse gas emissions which are estimated currently to be around 70 million tons per year. This significant growth of energy consumption impels network companies to pay huge bills which represent around half of their operating expenditures. Therefore, many service providers, including mobile operators, are looking for new and modern green solutions to help reduce their expenses as well as the level of their CO2 emissions. Base stations are the most power greedy element in cellular networks: they drain around 80% of the total network energy consumption even during low traffic periods. Thus, there is a growing need to develop more energy-efficient techniques to enhance the green performance of future 4G/5G cellular networks. Due to the problem of traffic load fluctuations in cellular networks during different periods of the day and between different areas (shopping or business districts and residential areas), the base station sleeping strategy has been one of the main popular research topics in green communications. In this presentation, we present several practical green techniques that provide significant gains for mobile operators. Indeed, combined with the base station sleeping strategy, these techniques achieve not only a minimization of the fossil fuel consumption but also an enhancement of mobile operator profits. We start with an optimized cell planning method that considers varying spatial and temporal user densities. We then use the optimal transport theory in order to define the cell boundaries such that the network total transmit power is reduced. Afterwards, we exploit the features of the modern electrical grid, the smart grid, as a new tool of power management for cellular networks and we optimize the energy procurement from multiple energy retailers characterized by different prices and pollutant

  11. A role of ghrelin in canine mammary carcinoma cells proliferation, apoptosis and migration

    Directory of Open Access Journals (Sweden)

    Majchrzak Kinga

    2012-09-01

    Full Text Available Abstract Background Ghrelin is a natural ligand of the growth hormone secretagogue receptor (GHS-R. They are often co-expressed in multiple human tumors and related cancer cell lines what can indicate that the ghrelin/GHS-R axis may have an important role in tumor growth and progression. However, a role of ghrelin in canine tumors remains unknown. Thus, the aim of our study was two-fold: (1 to assess expression of ghrelin and its receptor in canine mammary cancer and (2 to examine the effect of ghrelin on carcinoma cells proliferation, apoptosis, migration and invasion. The expression of ghrelin and its receptor in canine mammary cancer tissues and cell lines (isolated from primary tumors and their metastases was examined using Real-time qPCR and immunohistochemistry. For apoptosis analysis the Annexin V and propidium iodide dual staining was applied whereas cell proliferation was evaluated by MTT assay and BrdU incorporation test. The influence of ghrelin on cancer cells migration and invasion was assessed using Boyden chamber assays and wound healing assay. Results The highest expression of ghrelin was observed in metastatic cancers whereas the lowest expression of ghrelin receptor was detected in tumors of the 3rd grade of malignancy. Higher expression of ghrelin and its receptor was detected in cancer cell lines isolated from metastases than in cell lines isolated from primary tumors. In vitro experiments demonstrated that exposure to low doses of ghrelin stimulates cellular proliferation, inhibits apoptosis and promotes motility and invasion of canine mammary cancer cells. Growth hormone secretagogue receptor inhibitor ([D-Lys3]-GHRP6 as well as RNA interference enhances early apoptosis. Conclusion The presence of ghrelin and GHS-R in all of the examined canine mammary tumors may indicate their biological role in cancer growth and development. Our experiments conducted in vitro confirmed that ghrelin promotes cancer development and

  12. Interferon-Gamma-Induced Nitric Oxide Inhibits the Proliferation of Murine Renal Cell Carcinoma Cells

    Directory of Open Access Journals (Sweden)

    David J. Tate Jr., John R. Patterson, Cruz Velasco-Gonzalez, Emily N. Carroll, Janie Trinh, Daniel Edwards, Ashok Aiyar, Beatriz Finkel-Jimenez, Arnold H. Zea

    2012-01-01

    Full Text Available Renal cell carcinoma (RCC remains one of the most resistant tumors to systemic chemotherapy, radiotherapy, and immunotherapy. Despite great progress in understanding the basic biology of RCC, the rate of responses in animal models and clinical trials using interferons (IFNs has not improved significantly. It is likely that the lack of responses can be due to the tumor's ability to develop tumor escape strategies. Currently, the use of targeted therapies has improved the clinical outcomes of patients with RCC and is associated with an increase of Th1-cytokine responses (IFNγ, indicating the importance of IFNγ in inhibiting tumor proliferation. Thus, the present study was designed to investigate a new mechanism by which IFNγ mediates direct anti-proliferative effects against murine renal cell carcinoma cell lines. When cultured RCC cell lines were exposed to murine recombinant IFNγ, a dose dependent growth inhibition in CL-2 and CL-19 cells was observed; this effect was not observed in Renca cells. Growth inhibition in CL-2 and CL-19 cell lines was associated with the intracellular induction of nitric oxide synthase (iNOS protein, resulting in a sustained elevation of nitric oxide (NO and citrulline, and a decrease in arginase activity. The inhibition of cell proliferation appears to be due to an arrest in the cell cycle. The results indicate that in certain RCC cell lines, IFNγ modulates L-arginine metabolism by shifting from arginase to iNOS activity, thereby developing a potent inhibitory mechanism to encumber tumor cell proliferation and survival. Elucidating the cellular events triggered by IFNγ in murine RCC cell lines will permit anti-tumor effects to be exploited in the development of new combination therapies that interfere with L-arginine metabolism to effectively combat RCC in patients.

  13. Proliferation of luteal steroidogenic cells in cattle.

    Directory of Open Access Journals (Sweden)

    Shin Yoshioka

    Full Text Available The rapid growth of the corpus luteum (CL after ovulation is believed to be mainly due to an increase in the size of luteal cells (hypertrophy rather than an increase in their number. However, the relationship between luteal growth and the proliferation of luteal steroidogenic cells (LSCs is not fully understood. One goal of the present study was to determine whether LSCs proliferate during CL growth. A second goal was to determine whether luteinizing hormone (LH, which is known have roles in the proliferation and differentiation of follicular cells, also affects the proliferation of LSCs. Ki-67 (a cell proliferation marker was expressed during the early, developing and mid luteal stages and some Ki-67-positive cells co-expressed HSD3B (a steroidogenic marker. DNA content in LSCs isolated from the developing CL increased much more rapidly (indicating rapid growth than did DNA content in LSCs isolated from the mid CL. The cell cycle-progressive genes CCND2 (cyclin D2 and CCNE1 (cyclin E1 mRNA were expressed more strongly in the small luteal cells than in the large luteal cells. LH decreased the rate of increase of DNA in LSCs isolated from the mid luteal stage but not in LSCs from the developing stage. LH suppressed CCND2 expression in LSCs from the mid luteal stage but not from the developing luteal stage. Furthermore, LH receptor (LHCGR mRNA expression was higher at the mid luteal stage than at the developing luteal stage. The overall results suggest that the growth of the bovine CL is due to not only hypertrophy of LSCs but also an increase in their number, and that the proliferative ability of luteal steroidogenic cells decreases between the developing and mid luteal stages.

  14. Neuroprotective Effect of Uncaria rhynchophylla in Kainic Acid-Induced Epileptic Seizures by Modulating Hippocampal Mossy Fiber Sprouting, Neuron Survival, Astrocyte Proliferation, and S100B Expression

    Directory of Open Access Journals (Sweden)

    Chung-Hsiang Liu

    2012-01-01

    Full Text Available Uncaria rhynchophylla (UR, which is a traditional Chinese medicine, has anticonvulsive effect in our previous studies, and the cellular mechanisms behind this are still little known. Because of this, we wanted to determine the importance of the role of UR on kainic acid- (KA- induced epilepsy. Oral UR for 6 weeks can successfully attenuate the onset of epileptic seizure in animal tests. Hippocampal mossy fiber sprouting dramatically decreased, while neuronal survival increased with UR treatment in hippocampal CA1 and CA3 areas. Furthermore, oral UR for 6 weeks significantly attenuated the overexpression of astrocyte proliferation and S100B proteins but not γ-aminobutyric acid A (GABAA receptors. These results indicate that oral UR for 6 weeks can successfully attenuate mossy fiber sprouting, astrocyte proliferation, and S100B protein overexpression and increase neuronal survival in KA-induced epileptic rat hippocampus

  15. Proliferation resistance assessment of nuclear systems

    International Nuclear Information System (INIS)

    The first part of the present paper describes the basic assessment procedure that is adopted in the analysis of the three generic nuclear systems. Once-through, fast breeder, and thermal recycle systems are then treated in Sections II, III, and IV, respectively. In each of these sections, a reference system is examined, possible technical and institutional improvements are considered, and alternative system types are indicated. Section V then discusses the relative proliferation resistance of the three generic systems. Although this paper emphasizes the analysis and comparison of individual fuel cycle alternatives, Section V indicates briefly how these analyses then have to be considered in a broader context where systems coexist

  16. Cellular Pressure and Volume Regulation and Implications for Cell Mechanics

    OpenAIRE

    Jiang, Hongyuan; Sun, Sean X.

    2013-01-01

    In eukaryotic cells, small changes in cell volume can serve as important signals for cell proliferation, death, and migration. Volume and shape regulation also directly impacts the mechanics of cells and tissues. Here, we develop a mathematical model of cellular volume and pressure regulation, incorporating essential elements such as water permeation, mechanosensitive channels, active ion pumps, and active stresses in the cortex. The model can fully explain recent experimental data, and it pr...

  17. Cellular Manufacturing Systems: Organization, Trends And Innovative Methods

    OpenAIRE

    İŞLİER, Attila

    2015-01-01

    Interchangeability is the distinguishing feature of modern manufacturing. A huge production capacity to satisfy the people is reached thanks to that concept. Yet that prospect brought up a dilemma too. Efficient but inflexible flow lines for very limited product types on one side and unproductive flexible batch production for numerous diverse parts on the other side. The remedy is thought of as Cellular Manufacturing (CM). That seemed a brilliant idea but the proliferation of CM has never rea...

  18. Empirical multiscale networks of cellular regulation.

    Directory of Open Access Journals (Sweden)

    Benjamin de Bivort

    2007-10-01

    Full Text Available Grouping genes by similarity of expression across multiple cellular conditions enables the identification of cellular modules. The known functions of genes enable the characterization of the aggregate biological functions of these modules. In this paper, we use a high-throughput approach to identify the effective mutual regulatory interactions between modules composed of mouse genes from the Alliance for Cell Signaling (AfCS murine B-lymphocyte database which tracks the response of approximately 15,000 genes following chemokine perturbation. This analysis reveals principles of cellular organization that we discuss along four conceptual axes. (1 Regulatory implications: the derived collection of influences between any two modules quantifies intuitive as well as unexpected regulatory interactions. (2 Behavior across scales: trends across global networks of varying resolution (composed of various numbers of modules reveal principles of assembly of high-level behaviors from smaller components. (3 Temporal behavior: tracking the mutual module influences over different time intervals provides features of regulation dynamics such as duration, persistence, and periodicity. (4 Gene Ontology correspondence: the association of modules to known biological roles of individual genes describes the organization of functions within coexpressed modules of various sizes. We present key specific results in each of these four areas, as well as derive general principles of cellular organization. At the coarsest scale, the entire transcriptional network contains five divisions: two divisions devoted to ATP production/biosynthesis and DNA replication that activate all other divisions, an "extracellular interaction" division that represses all other divisions, and two divisions (proliferation/differentiation and membrane infrastructure that activate and repress other divisions in specific ways consistent with cell cycle control.

  19. Wnt9A Induction Linked to Suppression of Human Colorectal Cancer Cell Proliferation

    OpenAIRE

    Irshad Ali; Bani Medegan; Braun, Donald P

    2016-01-01

    Most studies of Wnt signaling in malignant tissues have focused on the canonical Wnt pathway (CWP) due to its role in stimulating cellular proliferation. The role of the non-canonical Wnt pathway (NCWP) in tissues with dysregulated Wnt signaling is not fully understood. Understanding NCWP’s role is important since these opposing pathways act in concert to maintain homeostasis in healthy tissues. Our preliminary studies demonstrated that LiCl inhibited proliferation of primary cells derived fr...

  20. Notch signaling modulates proliferation and differentiation of intestinal crypt base columnar stem cells

    OpenAIRE

    VanDussen, Kelli L; Carulli, Alexis J.; Keeley, Theresa M.; Patel, Sanjeevkumar R.; Puthoff, Brent J.; Magness, Scott T.; Tran, Ivy T.; Maillard, Ivan; Siebel, Christian; Kolterud, Åsa; Grosse, Ann S.; Gumucio, Deborah L; Ernst, Stephen A.; Tsai, Yu-Hwai; Dempsey, Peter J.

    2012-01-01

    Notch signaling is known to regulate the proliferation and differentiation of intestinal stem and progenitor cells; however, direct cellular targets and specific functions of Notch signals had not been identified. We show here in mice that Notch directly targets the crypt base columnar (CBC) cell to maintain stem cell activity. Notch inhibition induced rapid CBC cell loss, with reduced proliferation, apoptotic cell death and reduced efficiency of organoid initiation. Furthermore, expression o...

  1. Wp specific methylation of highly proliferated LCLs

    International Nuclear Information System (INIS)

    The epigenetic regulation of viral genes may be important for the life cycle of EBV. We determined the methylation status of three viral promoters (Wp, Cp, Qp) from EBV B-lymphoblastoid cell lines (LCLs) by pyrosequencing. Our pyrosequencing data showed that the CpG region of Wp was methylated, but the others were not. Interestingly, Wp methylation was increased with proliferation of LCLs. Wp methylation was as high as 74.9% in late-passage LCLs, but 25.6% in early-passage LCLs. From two Burkitt's lymphoma cell lines, Wp specific hypermethylation was also found (>80%). Interestingly, the expression of EBNA2 gene which located directly next to Wp was associated with its methylation. Our data suggested that Wp specific methylation may be important for the indicator of the proliferation status of LCLs, and the epigenetic viral gene regulation of EBNA2 gene by Wp should be further defined possibly with other biological processes

  2. Interferon-γ: biological function and application for study of cellular immune response

    Directory of Open Access Journals (Sweden)

    A. A. Lutckii

    2015-01-01

    Full Text Available Cellular immune response plays a central role in control of intracellular pathogens like viruses, some bacteria and parasites. Evaluation of presence, specificity and strength of cellular immune response can be done by investigation of reaction of immune cells to specific stimulus, like antigen. The major cellular reactions to antigen stimulation are production of cytokines, proliferation and cytotoxicity. This review is focused on interferon-gamma as one of the central Th1 cytokines: its biology, immunological role and application as marker of cellular immune response.

  3. Neural proliferation and restoration of neurochemical phenotypes and compromised functions following capsaicin-induced neuronal damage in the nodose ganglion of the adult rat.

    Directory of Open Access Journals (Sweden)

    Zachary Rex Gallaher

    2011-02-01

    Full Text Available We previously reported that neuronal numbers within adult nodose ganglia (NG were restored to normal levels 60 days following the capsaicin-induced destruction of nearly half of the neuronal population. However, the nature of this neuronal replacement is not known. Therefore, we aimed to characterize neural proliferation, neurochemical phenotypes, and functional recovery within adult rat NG neurons following capsaicin-induced damage. Sprague-Dawley rats received intraperitoneal injections of capsaicin or vehicle solution, followed by BrdU injections to reveal cellular proliferation. NG were collected at multiple times post-treatment (up to 300 days and processed for immunofluorescence, real-time RT-PCR, and dispersed cell cultures. Capsaicin-induced cellular proliferation, indicated by BrdU/Ki-67-labeled cells, suggests that lost neurons were replaced through cell division. NG cells expressed the stem cell marker, nestin, indicating that these ganglia have the capacity to generate new neurons. BrdU incorporation within beta-III tubulin-positive neuronal profiles following capsaicin suggests that proliferating cells matured to become neurons. NG neurons displayed decreased NMDAR expression up to 180 days post-capsaicin. However, both NMDAR expression within the NG and synaptophysin expression within the central target of NG neurons, the NTS, were restored to pre-injury levels by 300 days. NG cultures from capsaicin-treated rats contained bipolar neurons, normally found only during development. To test the functional recovery of NG neurons, we injected the satiety molecule, CCK. The effect of CCK on food intake was restored by 300 days post-capsaicin. This restoration may be due to the regeneration of damaged NG neurons or generation of functional neurons that replaced lost connections.

  4. Nuclear non proliferation and disarmament

    International Nuclear Information System (INIS)

    In the framework of the publication of a document on the ''weapons mastership, disarmament and non proliferation: the french action'', by the ministry of Foreign Affairs and the ministry of Defense, the French Documentation organization presents a whole document. This document describes and details the following topics: the conference on the treaty of non proliferation of nuclear weapons, the France, Usa and Non Governmental Organizations position, the threats of the proliferation, the french actions towards the disarmament, the disarmament in the world, a chronology and some bibliographic resources. (A.L.B.)

  5. Failover in cellular automata

    CERN Document Server

    Kumar, Shailesh

    2010-01-01

    A cellular automata (CA) configuration is constructed that exhibits emergent failover. The configuration is based on standard Game of Life rules. Gliders and glider-guns form the core messaging structure in the configuration. The blinker is represented as the basic computational unit, and it is shown how it can be recreated in case of a failure. Stateless failover using primary-backup mechanism is demonstrated. The details of the CA components used in the configuration and its working are described, and a simulation of the complete configuration is also presented.

  6. Cellular-scale hydrodynamics

    DEFF Research Database (Denmark)

    Abkarian, Manouk; Faivre, Magalie; Horton, Renita; Smistrup, Kristian; Best-Popescu, Catherine A; Stone, Howard A.

    2008-01-01

    Microfluidic tools are providing many new insights into the chemical, physical and physicochemical responses of cells. Both suspension-level and single-cell measurements have been studied. We review our studies of these kinds of problems for red blood cells with particular focus on the shapes of ...... mechanical effects on suspended cells can be studied systematically in small devices, and how these features can be exploited to develop methods for characterizing physicochemical responses and possibly for the diagnosis of cellular-scale changes to environmental factors....

  7. Cellular mechanics and motility

    Science.gov (United States)

    Hénon, Sylvie; Sykes, Cécile

    2015-10-01

    The term motility defines the movement of a living organism. One widely known example is the motility of sperm cells, or the one of flagellar bacteria. The propulsive element of such organisms is a cilium(or flagellum) that beats. Although cells in our tissues do not have a flagellum in general, they are still able to move, as we will discover in this chapter. In fact, in both cases of movement, with or without a flagellum, cell motility is due to a dynamic re-arrangement of polymers inside the cell. Let us first have a closer look at the propulsion mechanism in the case of a flagellum or a cilium, which is the best known, but also the simplest, and which will help us to define the hydrodynamic general conditions of cell movement. A flagellum is sustained by cellular polymers arranged in semi-flexible bundles and flagellar beating generates cell displacement. These polymers or filaments are part of the cellular skeleton, or "cytoskeleton", which is, in this case, external to the cellular main body of the organism. In fact, bacteria move in a hydrodynamic regime in which viscosity dominates over inertia. The system is thus in a hydrodynamic regime of low Reynolds number (Box 5.1), which is nearly exclusively the case in all cell movements. Bacteria and their propulsion mode by flagella beating are our unicellular ancestors 3.5 billion years ago. Since then, we have evolved to form pluricellular organisms. However, to keep the ability of displacement, to heal our wounds for example, our cells lost their flagellum, since it was not optimal in a dense cell environment: cells are too close to each other to leave enough space for the flagella to accomplish propulsion. The cytoskeleton thus developed inside the cell body to ensure cell shape changes and movement, and also mechanical strength within a tissue. The cytoskeleton of our cells, like the polymers or filaments that sustain the flagellum, is also composed of semi-flexible filaments arranged in bundles, and also in

  8. Radiolabelled Cellular Blood Elements

    International Nuclear Information System (INIS)

    This volume contains the abstracts of the 5th International Symposion on Radiolabelling of Cellular Blood Elements to be held in Vienna, Austria, September 10-14, 1989. The Meeting is the fifth in a series of meetings designed to discuss the basics and clinical application of radiolabelling techniques. In these days, beside the search for new labelling agents and extending the knowledge in clinical use, the use of monoclonal antibodies is a big new challenge. All reviewed contributions that have been accepted for presentation are contained in this volume. (authors) 58 of them are of INIS scope

  9. Toxicology and cellular effect of manufactured nanomaterials

    Science.gov (United States)

    Chen, Fanqing

    2014-07-22

    The increasing use of nanotechnology in consumer products and medical applications underlies the importance of understanding its potential toxic effects to people and the environment. Herein are described methods and assays to predict and evaluate the cellular effects of nanomaterial exposure. Exposing cells to nanomaterials at cytotoxic doses induces cell cycle arrest and increases apoptosis/necrosis, activates genes involved in cellular transport, metabolism, cell cycle regulation, and stress response. Certain nanomaterials induce genes indicative of a strong immune and inflammatory response within skin fibroblasts. Furthermore, the described multiwall carbon nanoonions (MWCNOs) can be used as a therapeutic in the treatment of cancer due to its cytotoxicity.

  10. The cellular decision between apoptosis and autophagy

    Directory of Open Access Journals (Sweden)

    Yong-Jun Fan

    2013-03-01

    Full Text Available Apoptosis and autophagy are important molecular processes that maintain organismal and cellular homeostasis, respectively. While apoptosis fulfills its role through dismantling damaged or unwanted cells, autophagy maintains cellular homeostasis through recycling selective intracellular organelles and molecules. Yet in some conditions, autophagy can lead to cell death. Apoptosis and autophagy can be stimulated by the same stresses. Emerging evidence indicates an interplay between the core proteins in both pathways, which underlies the molecular mechanism of the crosstalk between apoptosis and autophagy. This review summarizes recent literature on molecules that regulate both the apoptotic and autophagic processes.

  11. Hsp90 Is a Novel Target Molecule of CDDO-Me in Inhibiting Proliferation of Ovarian Cancer Cells.

    Science.gov (United States)

    Qin, Dong-Jun; Tang, Cai-Xia; Yang, Li; Lei, Hu; Wei, Wei; Wang, Ying-Ying; Ma, Chun-Min; Gao, Feng-Hou; Xu, Han-Zhang; Wu, Ying-Li

    2015-01-01

    Synthetic triterpenoid methyl-2-cyano-3, 12-dioxooleana-1, 9(11)-dien-28-oate (CDDO-Me) has been shown as a promising agent against ovarian cancer. However, the underlying mechanism is not well understood. Here, we demonstrate that CDDO-Me directly interacts with Hsp90 in cells by cellular thermal shift assay. CDDO-Me treatment leads to upregulation of Hsp70 and degradation of Hsp90 clients (ErbB2 and Akt), indicating the inhibition of Hsp90 by CDDO-Me in cells. Knockdown of Hsp90 significantly inhibits cell proliferation and enhances the anti-proliferation effect of CDDO-Me in H08910 ovarian cancer cells. Dithiothreitol inhibits the interaction of CDDO-Me with Hsp90 in cells and abrogates CDDO-Me induced upregulation of Hsp70, degradation of Akt and cell proliferation inhibition. This suggests the anti-ovarian cancer effect of CDDO-Me is possibly mediated by the formation of Michael adducts between CDDO-Me and reactive nucleophiles on Hsp90. This study identifies Hsp90 as a novel target protein of CDDO-Me, and provides a novel insight into the mechanism of action of CDDO-Me in ovarian cancer cells. PMID:26134508

  12. Hsp90 Is a Novel Target Molecule of CDDO-Me in Inhibiting Proliferation of Ovarian Cancer Cells.

    Directory of Open Access Journals (Sweden)

    Dong-Jun Qin

    Full Text Available Synthetic triterpenoid methyl-2-cyano-3, 12-dioxooleana-1, 9(11-dien-28-oate (CDDO-Me has been shown as a promising agent against ovarian cancer. However, the underlying mechanism is not well understood. Here, we demonstrate that CDDO-Me directly interacts with Hsp90 in cells by cellular thermal shift assay. CDDO-Me treatment leads to upregulation of Hsp70 and degradation of Hsp90 clients (ErbB2 and Akt, indicating the inhibition of Hsp90 by CDDO-Me in cells. Knockdown of Hsp90 significantly inhibits cell proliferation and enhances the anti-proliferation effect of CDDO-Me in H08910 ovarian cancer cells. Dithiothreitol inhibits the interaction of CDDO-Me with Hsp90 in cells and abrogates CDDO-Me induced upregulation of Hsp70, degradation of Akt and cell proliferation inhibition. This suggests the anti-ovarian cancer effect of CDDO-Me is possibly mediated by the formation of Michael adducts between CDDO-Me and reactive nucleophiles on Hsp90. This study identifies Hsp90 as a novel target protein of CDDO-Me, and provides a novel insight into the mechanism of action of CDDO-Me in ovarian cancer cells.

  13. Growth factor-rich plasma increases tendon cell proliferation and matrix synthesis on a synthetic scaffold: an in vitro study.

    Science.gov (United States)

    Visser, Lance C; Arnoczky, Steven P; Caballero, Oscar; Kern, Andreas; Ratcliffe, Anthony; Gardner, Keri L

    2010-03-01

    Numerous scaffolds have been proposed for use in connective tissue engineering. Although these scaffolds direct cell migration and attachment, many are biologically inert and thus lack the physiological stimulus to attract cells and induce mitogenesis and matrix synthesis. In the current study, a bioactive scaffold was created by combining a synthetic scaffold with growth factor-rich plasma (GFRP), an autologous concentration of growth factors derived from a platelet-rich plasma preparation. In vitro tendon cell proliferation and matrix synthesis on autologous GFRP-enriched scaffolds, autologous serum-enriched scaffolds, and scaffolds alone were compared. The GFRP preparation was found to have a 4.7-fold greater concentration of a sentinel growth factor (transforming growth factor-beta1) compared with serum. When combined with media containing calcium, the GFRP produced a thin fibrin matrix over and within the GFRP-enriched scaffolds. Cell proliferation assays demonstrated that GFRP-enriched scaffolds significantly enhanced cell proliferation over autologous serum and control groups at both 48 and 72 h. Analysis of the scaffolds at 14, 21, and 28 days revealed that GFRP-enriched scaffolds significantly increased the deposition of a collagen-rich extracellular matrix when compared with the other groups. These results indicate that GFRP can be used to enhance in vitro cellular population and matrix deposition of tissue-engineered scaffolds. PMID:19839921

  14. The thorny path linking cellular senescence to organismalaging

    Energy Technology Data Exchange (ETDEWEB)

    Patil, Christopher K.; Mian, Saira; Campisi, Judith

    2005-08-09

    Half a century is fast approaching since Hayflick and colleagues formally described the limited ability of normal human cells to proliferate in culture (Hayflick and Moorhead, 1961). This finding--that normal somatic cells, in contrast to cancer cells, cannot divide indefinitely--challenged the prevailing idea that cells from mortal multicellular organisms were intrinsically ''immortal'' (Carrell, 1912). It also spawned two hypotheses, essential elements of which persist today. The first held that the restricted proliferation of normal cells, now termed cellular senescence, suppresses cancer (Hayflick, 1965; Sager, 1991; Campisi, 2001). The second hypothesis, as explained in the article by Lorenzini et al., suggested that the limited proliferation of cells in culture recapitulated aspects of organismal aging (Hayflick, 1965; Martin, 1993). How well have these hypotheses weathered the ensuing decades? Before answering this question, we first consider current insights into the causes and consequences of cellular senescence. Like Lorenzini et al., we limit our discussion to mammals. We also focus on fibroblasts, the cell type studied by Lorenzini et al., but consider other types as well. We suggest that replicative capacity in culture is not a straightforward assessment, and that it correlates poorly with both longevity and body mass. We speculate this is due to the malleable and variable nature of replicative capacity, which renders it an indirect metric of qualitative and quantitative differences among cells to undergo senescence, a response that directly alters cellular phenotype and might indirectly alter tissue structure and function.

  15. Ki-67 Proliferation Index in Gastric Cancer - Biologic Significance

    OpenAIRE

    Nabais, C.; Caldeira Fradique, A; Oliveira, M.; Quaresma, L.; Gualdino Silva, J; Vasconcelos, V.; Sacadura, J.; Costa, L; Cabrita, F; Mateus Marques, R; Esteves, J.; Fernandez, G.; Guedes da Silva

    2016-01-01

    Objectives/Introdution: Ki-67 protein has been used as an indicator of proliferation activity in tumor cells. In gastric cancer the prognostic value has not been fully understood. This study was designed to assess the biologic significance of Ki-67 proliferation index (PI) in gastric cancer. Material/Methods: Seventy-two patients with gastric cancer were evaluated. These patients underwent gastric resection, and the tumor tissue was stained immunohistochemically. Ki-67 PI was defi...

  16. Morphology, proliferation, and osteogenic differentiation of mesenchymal stem cells cultured on titanium, tantalum, and chromium surfaces

    DEFF Research Database (Denmark)

    Stiehler, Maik; Lind, M.; Mygind, Tina;

    2007-01-01

    interactions between human mesenchymal stem cells (MSCs) and smooth surfaces of titanium (Ti), tantalum (Ta), and chromium (Cr). Mean cellular area was quantified using fluorescence microscopy (4 h). Cellular proliferation was assessed by (3)H-thymidine incorporation and methylene blue cell counting assays (4...... other surfaces tested. Cells cultured on Cr demonstrated reduced spreading and proliferation. In conclusion, Ta metal, as an alternative for Ti, can be considered as a promising biocompatible material, whereas further studies are needed to fully understand the role of Cr and its alloys in bone implants...

  17. Spatial distribution and cellular composition of adult brain proliferative zones in the teleost, Gymnotus omarorum

    Directory of Open Access Journals (Sweden)

    Daniel A Peterson

    2014-09-01

    Full Text Available Proliferation of stem/progenitor cells during development provides for the generation of mature cell types in the CNS. While adult brain proliferation is highly restricted in the mammals, it is widespread in teleosts. The extent of adult neural proliferation in the weakly electric fish, Gymnotus omarorum has not yet been described. To address this, we used double thymidine analog pulse-chase labeling of proliferating cells to identify brain proliferation zones, characterize their cellular composition, and analyze the fate of newborn cells in adult G. omarorum. Short thymidine analog chase periods revealed the ubiquitous distribution of adult brain proliferation, similar to other teleosts, particularly Apteronotus leptorhynchus. Proliferating cells were abundant at the ventricular-subventricular lining of the ventricular-cisternal system, adjacent to the telencephalic subpallium, the diencephalic preoptic region and hypothalamus, and the mesencephalic tectum opticum and torus semicircularis. Extraventricular proliferation zones, located distant from the ventricular-cisternal system surface, were found in all divisions of the rombencephalic cerebellum. We also report a new adult proliferation zone at the caudal-lateral border of the electrosensory lateral line lobe. All proliferation zones showed a heterogeneous cellular composition. The use of short (24hs and long (30d chase periods revealed abundant fast cycling cells (potentially intermediate amplifiers, sparse slow cycling (potentially stem cells, cells that appear to have entered a quiescent state, and cells that might correspond to migrating newborn neural cells. Their abundance and migration distance differed among proliferation zones: greater numbers and longer range and/or pace of migrating cells were associated with subpallial and cerebellar proliferation zones.

  18. Ginsenosides stimulated the proliferation of mouse spermatogonia involving activation of protein kinase C

    Institute of Scientific and Technical Information of China (English)

    Da-lei ZHANG; Kai-ming WANG; Cai-qiao ZHANG

    2009-01-01

    The effect of ginsenosides on proliferation of type A spermatogonia was investigated in 7-day-old mice.Spermatogonia were characterized by c-kit expression and cell proliferation was assessed by immunocytochemical demonstration of proliferating cell nuclear antigen (PCNA).After 72-h culture,Sertoli cells formed a confluent monolayer to which numerous spermatogonial colonies attached.Spermatogonia were positive for c-kit staining and showed high proliferating activity by PCNA expression.Ginsenosides (1.0~10 μg/ml) significantly stimulated proliferation of spermatogonia.Activation of protein kinase C (PKC) elicited proliferation of spermatogonia at 10-8 to 107 mol/L and the PKC inhibitor H7 inhibited this effect.Likewise,ginsenosides-stimulated spermatogonial proliferation was suppressed by combined treatment of H7.These results indicate that the proliferating effect ofginsenosides on mouse type A spermatogonia might be mediated by a mechanism involving the PKC signal transduction pathway.

  19. Inhibition of human copper trafficking by a small molecule significantly attenuates cancer cell proliferation

    Science.gov (United States)

    Wang, Jing; Luo, Cheng; Shan, Changliang; You, Qiancheng; Lu, Junyan; Elf, Shannon; Zhou, Yu; Wen, Yi; Vinkenborg, Jan L.; Fan, Jun; Kang, Heebum; Lin, Ruiting; Han, Dali; Xie, Yuxin; Karpus, Jason; Chen, Shijie; Ouyang, Shisheng; Luan, Chihao; Zhang, Naixia; Ding, Hong; Merkx, Maarten; Liu, Hong; Chen, Jing; Jiang, Hualiang; He, Chuan

    2015-12-01

    Copper is a transition metal that plays critical roles in many life processes. Controlling the cellular concentration and trafficking of copper offers a route to disrupt these processes. Here we report small molecules that inhibit the human copper-trafficking proteins Atox1 and CCS, and so provide a selective approach to disrupt cellular copper transport. The knockdown of Atox1 and CCS or their inhibition leads to a significantly reduced proliferation of cancer cells, but not of normal cells, as well as to attenuated tumour growth in mouse models. We show that blocking copper trafficking induces cellular oxidative stress and reduces levels of cellular ATP. The reduced level of ATP results in activation of the AMP-activated protein kinase that leads to reduced lipogenesis. Both effects contribute to the inhibition of cancer cell proliferation. Our results establish copper chaperones as new targets for future developments in anticancer therapies.

  20. Hsp90 inhibitor 17-allylamino-17-demethoxygeldanamycin inhibits the proliferation of ARPE-19 cells

    Directory of Open Access Journals (Sweden)

    Wang Lin

    2010-04-01

    Full Text Available Abstract Background The antiproliferative effect of the Hsp90 inhibitor 17-AAG (17-allylamino-17-demethoxygeldanamycin on human retinal pigment epithelial cells is investigated. Methods MTT and flow cytometry were used to study the antiproliferative effects of the 17-AAG treatment of ARPE-19 cells. 2D gel electrophoresis (2-DE and mass spectrometry were applied to detect the altered expression of proteins, which was verified by real-time PCR. Gene Ontology analysis and Ingenuity Pathway Analysis (IPA were utilized to analyze the signaling pathways, cellular location, function, and network connections of the identified proteins. And SOD assay was employed to confirm the analysis. Results 17-AAG suppressed the proliferation of ARPE-19 cells by inducing cell cycle arrest and apoptosis. Proteomic analysis revealed that the expression of 94 proteins was altered by a factor of more than 1.5 following exposure to 17-AAG. Of these 94, 87 proteins were identified. Real-time PCR results indicated that Hsp90 and Hsp70, which were not identified by proteomic analysis, were both upregulated upon 17-AAG treatment. IPA revealed that most of the proteins have functions that are related to oxidative stress, as verified by SOD assay, while canonical pathway analysis revealed glycolysis/gluconeogenesis. Conclusions 17-AAG suppressed the proliferation of ARPE-19 cells by inducing cell cycle arrest and apoptosis, and possibly by oxidative stress.

  1. Human hepatitis B viral e antigen and its precursor P20 inhibit T lymphocyte proliferation

    Energy Technology Data Exchange (ETDEWEB)

    Purvina, Maija; Hoste, Astrid; Rossignol, Jean-Michel [Universite de Versailles-Saint-Quentin-en-Yvelines, Laboratoire de Genetique et Biologie Cellulaire, EA 4589, 45 avenue des Etats-Unis, 78035 Versailles (France); Lagaudriere-Gesbert, Cecile, E-mail: cecile.lagaudriere-gesbert@u-psud.fr [Universite de Versailles-Saint-Quentin-en-Yvelines, Laboratoire de Genetique et Biologie Cellulaire, EA 4589, 45 avenue des Etats-Unis, 78035 Versailles (France)

    2012-01-27

    Highlights: Black-Right-Pointing-Pointer P20, precursor of the HBeAg, interacts with the cellular protein gC1qR. Black-Right-Pointing-Pointer HBeAg and P20 bind to T cell surface and inhibit mitogen-induced T cell division. Black-Right-Pointing-Pointer HBeAg and P20 inhibition of T cell proliferation is gC1qR and IL-1RAcP-independent. -- Abstract: The hepatitis B virus (HBV) Precore protein is processed through the secretory pathway directly as HBeAg or with the generation of an intermediate (P20). Precore gene has been shown to be implicated in viral persistence, but the functions of HBeAg and its precursors have not been fully elucidated. We show that the secreted proteins HBeAg and P20 interact with T cell surface and alter Kit-225 and primary T cells proliferation, a process which may facilitate the establishment of HBV persistence. Our data indicate that the N-terminal end of Precore is important for these inhibitory effects and exclude that they are dependent on the association of HBeAg and P20 with two characterized cell surface ligands, the Interleukin-1 Receptor Accessory Protein and gC1qR (present study).

  2. Vimentin expression influences flow dependent VASP phosphorylation and regulates cell migration and proliferation

    International Nuclear Information System (INIS)

    The cytoskeleton plays a central role for the integration of biochemical and biomechanical signals across the cell required for complex cellular functions. Recent studies indicate that the intermediate filament vimentin is necessary for endothelial cell morphogenesis e.g. in the context of leukocyte transmigration. Here, we present evidence, that the scaffold provided by vimentin is essential for VASP localization and PKG mediated VASP phosphorylation and thus controls endothelial cell migration and proliferation. Vimentin suppression using siRNA technique significantly decreased migration velocity by 50% (videomicroscopy), diminished transmigration activity by 42.5% (Boyden chamber) and reduced proliferation by 43% (BrdU-incorporation). In confocal microscopy Vimentin colocalized with VASP and PKG in endothelial cells. Vimentin suppression was accompanied with a translocation of VASP from focal contacts to the perinuclear region. VASP/Vimentin and PKG/Vimentin colocalization appeared to be essential for proper PKG mediated VASP phosphorylation because we detected a diminished expression of PKG and pSer239-VASP in vimentin-suppressed cells, Furthermore, the induction of VASP phosphorylation in perfused arteries was markedly decreased in vimentin knockout mice compared to wildtypes. A link is proposed between vimentin, VASP phosphorylation and actin dynamics that delivers an explanation for the important role of vimentin in controlling endothelial cell morphogenesis.

  3. MicroRNA-153 inhibits osteosarcoma cells proliferation and invasion by targeting TGF-β2.

    Directory of Open Access Journals (Sweden)

    Guangfeng Niu

    Full Text Available Increasing evidence indicates that microRNAs (miRNAs, a class of small noncoding RNAs, participate in almost every step of cellular processes. MiRNAs are aberrantly expressed in human cancers and contribute to cancer development and progression. Study of miRNAs may provide a new clue for understanding the mechanism of carcinogenesis and a new tool for cancer treatment. In the present study, miR-153 was downregulated in human osteosarcoma tissues and cell lines. Introduction of miR-153 mimics into the MG-63 cells inhibited cell proliferation and invasion. Our results further revealed that transforming growth factor beta 2 (TGF-β2 was negatively regulated by miR-153. Furthermore, overexpression of miR-153 decreased p-SMAD2, p-SMAD3, epidermal growth factor receptor (EGFR and insulin-like growth factor binding protein-3 (IGFBP-3 expressions, which were the downstream signaling molecules of TGF-β. Furthermore, miRNA-153 suppressed TGF-β-mediated MG-63 proliferation and migration. Therefore, our results suggest that miR-153 may act as a tumor suppressor in osteosarcoma through targeting TGF-β2.

  4. The rapamycin analog CCI-779 is a potent inhibitor of pancreatic cancer cell proliferation

    International Nuclear Information System (INIS)

    We present immunohistochemical evidence that the mTOR/p70s6k pathway is activated in pancreatic tumors and show that the mTOR inhibitor and rapamycin analog CCI-779 potently suppresses the proliferation of pancreatic cancer cells. Consistent with a recent study, CCI-779 increased c-Jun phosphorylation (Ser63) in a dose- and time-dependent manner, and induced apoptosis in p53-defective BxPC-3 cells. In contrast to the study, however, we observed that CCI-779 concomitantly increased c-Jun protein levels and that its ability to induce apoptosis might not require the activated c-Jun. Furthermore, CCI-779 neither induced c-Jun phosphorylation in other p53-defective pancreatic cancer cells (MiaPaCa-2) nor inhibited their proliferation. c-Jun, in fact, appeared to be partly responsible for the resistance of MiaPaCa-2 cells to CCI-779. Together, these results indicate a complex role for c-Jun in cellular responses to CCI-779 and provide an important basis for investigating CCI-779 further as a potential therapeutic agent for pancreatic tumors

  5. ADP-Ribosylation Factor 1 Regulates Proliferation, Migration, and Fusion in Early Stage of Osteoclast Differentiation

    Directory of Open Access Journals (Sweden)

    Min Jae Kim

    2015-12-01

    Full Text Available Small G-protein adenosine diphosphate (ADP-ribosylation factors (ARFs regulate a variety of cellular functions, including actin cytoskeleton remodeling, plasma membrane reorganization, and vesicular transport. Here, we propose the functional roles of ARF1 in multiple stages of osteoclast differentiation. ARF1 was upregulated during receptor activator of nuclear factor kappa-B ligand (RANKL-induced osteoclast differentiation and transiently activated in an initial stage of their differentiation. Differentiation of ARF1-deficient osteoclast precursors into mature osteoclasts temporarily increased in pre-maturation stage of osteoclasts followed by reduced formation of mature osteoclasts, indicating that ARF1 regulates the osteoclastogenic process. ARF1 deficiency resulted in reduced osteoclast precursor proliferation and migration as well as increasing cell-cell fusion. In addition, ARF1 silencing downregulated c-Jun N-terminal kinase (JNK, Akt, osteopontin, and macrophage colony-stimulating factor (M-CSF-receptor c-Fms as well as upregulating several fusion-related genes including CD44, CD47, E-cadherin, and meltrin-α. Collectively, we showed that ARF1 stimulated proliferation and migration of osteoclast precursors while suppressing their fusion, suggesting that ARF1 may be a plausible inter-player that mediates the transition to osteoclast fusion at multiple steps during osteoclast differentiation

  6. In Vitro Effects of Strontium on Proliferation and Osteoinduction of Human Preadipocytes

    Directory of Open Access Journals (Sweden)

    V. Nardone

    2015-01-01

    Full Text Available Development of tools to be used for in vivo bone tissue regeneration focuses on cellular models and differentiation processes. In searching for all the optimal sources, adipose tissue-derived mesenchymal stem cells (hADSCs or preadipocytes are able to differentiate into osteoblasts with analogous characteristics to bone marrow mesenchymal stem cells, producing alkaline phosphatase (ALP, collagen, osteocalcin, and calcified nodules, mainly composed of hydroxyapatite (HA. The possibility to influence bone differentiation of stem cells encompasses local and systemic methods, including the use of drugs administered systemically. Among the latter, strontium ranelate (SR represents an interesting compound, acting as an uncoupling factor that stimulates bone formation and inhibits bone resorption. The aim of our study was to evaluate the in vitro effects of a wide range of strontium (Sr2+ concentrations on proliferation, ALP activity, and mineralization of a novel finite clonal hADSCs cell line, named PA20-h5. Sr2+ promoted PA20-h5 cell proliferation while inducing the increase of ALP activity and gene expression as well as HA production during in vitro osteoinduction. These findings indicate a role for Sr2+ in supporting bone regeneration during the process of skeletal repair in general, and, more specifically, when cell therapies are applied.

  7. Human hepatitis B viral e antigen and its precursor P20 inhibit T lymphocyte proliferation

    International Nuclear Information System (INIS)

    Highlights: ► P20, precursor of the HBeAg, interacts with the cellular protein gC1qR. ► HBeAg and P20 bind to T cell surface and inhibit mitogen-induced T cell division. ► HBeAg and P20 inhibition of T cell proliferation is gC1qR and IL-1RAcP-independent. -- Abstract: The hepatitis B virus (HBV) Precore protein is processed through the secretory pathway directly as HBeAg or with the generation of an intermediate (P20). Precore gene has been shown to be implicated in viral persistence, but the functions of HBeAg and its precursors have not been fully elucidated. We show that the secreted proteins HBeAg and P20 interact with T cell surface and alter Kit-225 and primary T cells proliferation, a process which may facilitate the establishment of HBV persistence. Our data indicate that the N-terminal end of Precore is important for these inhibitory effects and exclude that they are dependent on the association of HBeAg and P20 with two characterized cell surface ligands, the Interleukin-1 Receptor Accessory Protein and gC1qR (present study).

  8. Low power laser and LED irradiation effect on proliferation and differentiation of Wistar rats mesenchymal stem cells

    Science.gov (United States)

    Mancera, Diana; Solarte, Efrain; Fierro, Leonardo; Criollo, William

    2013-11-01

    It has been demonstrated that appropriately cultured and stimulated mesenchymal cells, can give rise to cells of all tissues of the body. We evaluate the cell proliferation and differentiation induced by low power light irradiation in cell cultures of mesenchymal cells, isolated and previously characterized, from Wistar rats. Roche® XTT and LDH tests were used to assess proliferation and cytotoxicity. Cellular differentiation was determined by optical microscopy and using specific fluorescent markers. We report laser cellular proliferation enhancement by 532 and 473 nm, and the best cell culture response by a dose of 2 Jcm-2. Although a three day irradiation protocol the cultures grown and no cytotoxicity was detected. Cellular differentiation occurred, and the production of cardiomyocytes was promoted by the cell proliferation stimulated by low power laser irradiation.

  9. Cellular resistance to HIV-1 infection in target cells coincides with a rapid induction of X-DING-CD4 mRNA: indication of the unique host innate response to virus regulated through function of the X-DING-CD4 gene.

    Science.gov (United States)

    Shilpi, Rasheda Y; Sachdeva, Rakhee; Simm, Malgorzata

    2012-08-01

    Clinical reports indicate that some infected individuals control HIV-1 replication through undefined mechanisms. Our group reported that a human protein named X-DING-CD4 holds a potent antiviral activity, blocking transcription of HIV-1 LTR through the inhibition of NF-κB/DNA binding. Based on observations that transformed HIV-1 resistant CD4(+) T cells produce higher levels of soluble X-DING-CD4 protein upon their exposure to virus, we hypothesized that resistance to HIV-1 in these cells may be regulated through function of the X-DING-CD4 gene. Real-time PCR evaluations of X-DING-CD4 mRNA expression confirmed our hypothesis; HIV-1 exposure caused rapid up-regulation of X-DING-CD4 mRNA in resistant, but not susceptible, cells; and the burst of X-DING-CD4 mRNA expression correlated with restriction of HIV-1 transcription. Subsequently, we examined the activity of the X-DING-CD4 gene in monocytes and macrophages from (n = 13) HIV-negative donors. The assessment of HIV-1 gag mRNA showed that the majority of cells were permissive to virus replication; however, macrophages from four donors were refractory to HIV-1 infection. In response to virus, these cells up-regulated X-DING-CD4 gene expression by 2- to 1000-fold. These data provide evidence that the X-DING-CD4 gene contributes to early cellular protection from HIV infection in some individuals and this protection depends solely on the unique genetic regulation of the host. PMID:22042911

  10. Simvastatin modulates mesenchymal stromal cell proliferation and gene expression.

    Science.gov (United States)

    Zanette, Dalila Lucíola; Lorenzi, Julio Cesar Cetrulo; Panepucci, Rodrigo Alexandre; Palma, Patricia Vianna Bonini; Dos Santos, Daiane Fernanda; Prata, Karen Lima; Silva, Wilson Araújo

    2015-01-01

    Statins are widely used hypocholesterolemic drugs that block the mevalonate pathway, responsible for the biosysnthesis of cholesterol. However, statins also have pleiotropic effects that interfere with several signaling pathways. Mesenchymal stromal cells (MSC) are a heterogeneous mixture of cells that can be isolated from a variety of tissues and are identified by the expression of a panel of surface markers and by their ability to differentiate in vitro into osteocytes, adipocytes and chondrocytes. MSC were isolated from amniotic membranes and bone marrows and characterized based on ISCT (International Society for Cell Therapy) minimal criteria. Simvastatin-treated cells and controls were directly assayed by CFSE (Carboxyfluorescein diacetate succinimidyl ester) staining to assess their cell proliferation and their RNA was used for microarray analyses and quantitative PCR (qPCR). These MSC were also evaluated for their ability to inhibit PBMC (peripheral blood mononuclear cells) proliferation. We show here that simvastatin negatively modulates MSC proliferation in a dose-dependent way and regulates the expression of proliferation-related genes. Importantly, we observed that simvastatin increased the percentage of a subset of smaller MSC, which also were actively proliferating. The association of MSC decreased size with increased pluripotency and the accumulating evidence that statins may prevent cellular senescence led us to hypothesize that simvastatin induces a smaller subpopulation that may have increased ability to maintain the entire pool of MSC and also to protect them from cellular senescence induced by long-term cultures/passages in vitro. These results may be important to better understand the pleiotropic effects of statins and its effects on the biology of cells with regenerative potential. PMID:25874574

  11. Simvastatin modulates mesenchymal stromal cell proliferation and gene expression.

    Directory of Open Access Journals (Sweden)

    Dalila Lucíola Zanette

    Full Text Available Statins are widely used hypocholesterolemic drugs that block the mevalonate pathway, responsible for the biosysnthesis of cholesterol. However, statins also have pleiotropic effects that interfere with several signaling pathways. Mesenchymal stromal cells (MSC are a heterogeneous mixture of cells that can be isolated from a variety of tissues and are identified by the expression of a panel of surface markers and by their ability to differentiate in vitro into osteocytes, adipocytes and chondrocytes. MSC were isolated from amniotic membranes and bone marrows and characterized based on ISCT (International Society for Cell Therapy minimal criteria. Simvastatin-treated cells and controls were directly assayed by CFSE (Carboxyfluorescein diacetate succinimidyl ester staining to assess their cell proliferation and their RNA was used for microarray analyses and quantitative PCR (qPCR. These MSC were also evaluated for their ability to inhibit PBMC (peripheral blood mononuclear cells proliferation. We show here that simvastatin negatively modulates MSC proliferation in a dose-dependent way and regulates the expression of proliferation-related genes. Importantly, we observed that simvastatin increased the percentage of a subset of smaller MSC, which also were actively proliferating. The association of MSC decreased size with increased pluripotency and the accumulating evidence that statins may prevent cellular senescence led us to hypothesize that simvastatin induces a smaller subpopulation that may have increased ability to maintain the entire pool of MSC and also to protect them from cellular senescence induced by long-term cultures/passages in vitro. These results may be important to better understand the pleiotropic effects of statins and its effects on the biology of cells with regenerative potential.

  12. Cellular interactions via conditioned media induce in vivo nephron generation from tubular epithelial cells or mesenchymal stem cells

    International Nuclear Information System (INIS)

    Highlights: •We have attempted in vivo nephron generation using conditioned media. •Vascular and tubular cells do cross-talks on cell proliferation and tubular changes. •Tubular cells suppress these changes in mesenchymal stem cells. •Tubular cells differentiate mesenchymal stem cells into tubular cells. •Nephrons can be created from implanted tubular cells or mesenchymal stem cells. -- Abstract: There are some successful reports of kidney generation by utilizing the natural course of kidney development, namely, the use of an artificially treated metanephros, blastocyst or ureteric bud. Under a novel concept of cellular interactions via conditioned media (CMs), we have attempted in vivo nephron generation from tubular epithelial cells (TECs) or mesenchymal stem cells (MSCs). Here we used 10× CMs of vascular endothelial cells (VECs) and TECs, which is the first to introduce a CM into the field of organ regeneration. We first present stimulative cross-talks induced by these CMs between VECs and TECs on cell proliferation and morphological changes. In MSCs, TEC-CM suppressed these changes, however, induced cytokeratin expression, indicating the differentiation of MSCs into TECs. As a result, glomerular and tubular structures were created following the implantation of TECs or MSCs with both CMs. Our findings suggest that the cellular interactions via CMs might induce in vivo nephron generation from TECs or MSCs. As a promoting factor, CMs could also be applied to the regeneration of other organs and tissues

  13. HSV-1 nucleocapsid egress mediated by UL31 in association with UL34 is impeded by cellular transmembrane protein 140

    International Nuclear Information System (INIS)

    During HSV-1 infection, the viral UL31 protein forms a complex with the UL34 protein at the cellular nuclear membrane, where both proteins play important roles in the envelopment of viral nucleocapsids and their egress into the cytoplasm. To characterize the mechanism of HSV-1 nucleocapsid egress, we screened host proteins to identify proteins that interacted with UL31 via yeast two-hybrid analysis. Transmembrane protein 140 (TMEM140), was identified and confirmed to bind to and co-localize with UL31 during viral infection. Further studies indicated that TMEM140 inhibits HSV-1 proliferation through selectively blocking viral nucleocapsid egress during the viral assembly process. The blockage function of TMEM140 is mediated by impeding the formation of the UL31–UL34 complex due to competitive binding to UL31. Collectively, these data suggest the essentiality of the UL31–UL34 interaction in the viral nucleocapsid egress process and provide a new anti-HSV-1 strategy in viral assembly process of nucleocapsid egress. - Highlights: • Cellular TMEM140 protein interacts with HSV-1 UL31 protein during viral infection. • Increasing expression of TMEM140 leads to inhibition of HSV-1 proliferation. • Increasing expression of TMEM140 blocks HSV-1 nucleocapsid egress process. • Binding to UL31 of TMEM140 impedes formation of HSV-1 UL31–UL34 complex

  14. Cellular interactions via conditioned media induce in vivo nephron generation from tubular epithelial cells or mesenchymal stem cells

    Energy Technology Data Exchange (ETDEWEB)

    Machiguchi, Toshihiko, E-mail: machiguchi.toshihiko.23u@st.kyoto-u.ac.jp; Nakamura, Tatsuo, E-mail: nakamura@frontier.kyoto-u.ac.jp

    2013-06-07

    Highlights: •We have attempted in vivo nephron generation using conditioned media. •Vascular and tubular cells do cross-talks on cell proliferation and tubular changes. •Tubular cells suppress these changes in mesenchymal stem cells. •Tubular cells differentiate mesenchymal stem cells into tubular cells. •Nephrons can be created from implanted tubular cells or mesenchymal stem cells. -- Abstract: There are some successful reports of kidney generation by utilizing the natural course of kidney development, namely, the use of an artificially treated metanephros, blastocyst or ureteric bud. Under a novel concept of cellular interactions via conditioned media (CMs), we have attempted in vivo nephron generation from tubular epithelial cells (TECs) or mesenchymal stem cells (MSCs). Here we used 10× CMs of vascular endothelial cells (VECs) and TECs, which is the first to introduce a CM into the field of organ regeneration. We first present stimulative cross-talks induced by these CMs between VECs and TECs on cell proliferation and morphological changes. In MSCs, TEC-CM suppressed these changes, however, induced cytokeratin expression, indicating the differentiation of MSCs into TECs. As a result, glomerular and tubular structures were created following the implantation of TECs or MSCs with both CMs. Our findings suggest that the cellular interactions via CMs might induce in vivo nephron generation from TECs or MSCs. As a promoting factor, CMs could also be applied to the regeneration of other organs and tissues.

  15. HSV-1 nucleocapsid egress mediated by UL31 in association with UL34 is impeded by cellular transmembrane protein 140

    Energy Technology Data Exchange (ETDEWEB)

    Guan, Ying [Department of Viral Immunology, Institute of Medical Biology, Chinese Academy of Medicine Science, Peking Union Medical College, Kunming 650118 (China); Yunnan Academy of Tobacco Science, Kunming, Yunnan 650106 (China); Guo, Lei; Yang, Erxia; Liao, Yun; Liu, Longding; Che, Yanchun; Zhang, Ying; Wang, Lichun; Wang, Jingjing [Department of Viral Immunology, Institute of Medical Biology, Chinese Academy of Medicine Science, Peking Union Medical College, Kunming 650118 (China); Li, Qihan, E-mail: imbcams.lq@gmail.com [Department of Viral Immunology, Institute of Medical Biology, Chinese Academy of Medicine Science, Peking Union Medical College, Kunming 650118 (China)

    2014-09-15

    During HSV-1 infection, the viral UL31 protein forms a complex with the UL34 protein at the cellular nuclear membrane, where both proteins play important roles in the envelopment of viral nucleocapsids and their egress into the cytoplasm. To characterize the mechanism of HSV-1 nucleocapsid egress, we screened host proteins to identify proteins that interacted with UL31 via yeast two-hybrid analysis. Transmembrane protein 140 (TMEM140), was identified and confirmed to bind to and co-localize with UL31 during viral infection. Further studies indicated that TMEM140 inhibits HSV-1 proliferation through selectively blocking viral nucleocapsid egress during the viral assembly process. The blockage function of TMEM140 is mediated by impeding the formation of the UL31–UL34 complex due to competitive binding to UL31. Collectively, these data suggest the essentiality of the UL31–UL34 interaction in the viral nucleocapsid egress process and provide a new anti-HSV-1 strategy in viral assembly process of nucleocapsid egress. - Highlights: • Cellular TMEM140 protein interacts with HSV-1 UL31 protein during viral infection. • Increasing expression of TMEM140 leads to inhibition of HSV-1 proliferation. • Increasing expression of TMEM140 blocks HSV-1 nucleocapsid egress process. • Binding to UL31 of TMEM140 impedes formation of HSV-1 UL31–UL34 complex.

  16. Mechanical trapping of the nucleus on micropillared surfaces inhibits the proliferation of vascular smooth muscle cells but not cervical cancer HeLa cells.

    Science.gov (United States)

    Nagayama, Kazuaki; Hamaji, Yumi; Sato, Yuji; Matsumoto, Takeo

    2015-07-16

    The interaction between cells and the extracellular matrix on a topographically patterned surface can result in changes in cell shape and many cellular functions. In the present study, we demonstrated the mechanical deformation and trapping of the intracellular nucleus using polydimethylsiloxane (PDMS)-based microfabricated substrates with an array of micropillars. We investigated the differential effects of nuclear deformation on the proliferation of healthy vascular smooth muscle cells (SMCs) and cervical cancer HeLa cells. Both types of cell spread normally in the space between micropillars and completely invaded the extracellular microstructures, including parts of their cytoplasm and their nuclei. We found that the proliferation of SMCs but not HeLa cells was dramatically inhibited by cultivation on the micropillar substrates, even though remarkable deformation of nuclei was observed in both types of cells. Mechanical testing with an atomic force microscope and a detailed image analysis with confocal microscopy revealed that SMC nuclei had a thicker nuclear lamina and greater expression of lamin A/C than those of HeLa cells, which consequently increased the elastic modulus of the SMC nuclei and their nuclear mechanical resistance against extracellular microstructures. These results indicate that the inhibition of cell proliferation resulted from deformation of the mature lamin structures, which might be exposed to higher internal stress during nuclear deformation. This nuclear stress-induced inhibition of cell proliferation occurred rarely in cancer cells with deformable nuclei. PMID:26054426

  17. The Role of Neonatal Carnitine Palmitoyl Transferase Deficiency Type II on Proliferation of Neuronal Progenitor Cells and Layering of the Cerebral Cortex in the Developing Brain

    Directory of Open Access Journals (Sweden)

    Heepeel Chang

    2007-06-01

    Full Text Available Neonatal Carnitine Palmitoyl Transferase Deficiency Type II, characterized by the absence of CPT II enzyme, is one of the lethal disorders of mitochondrial fatty acid oxidation. CPT II regulates the conversion of long chain fatty acids, so that its product, acyl-CoA esters, can enter the Krebs cycle and generate energy. Neonatal mutations of CPT II lead to severe disruption of the metabolism of long-chain fatty acids and result in dysmorphic features, cystic renal dysplasia, and neuronal migration defects. Examination of the brain from an approximately 15-week gestation human fetus with CPT II deficiency revealed premature formation of cerebral cortical gyri and sulci and significantly lower levels of neuronal cell proliferation in the ventricular and subventricular zones as compared to the reference cases. We used immunohistochemical markers to further characterize the effect of CPT II deficiency on progenitor cell proliferation and layering of neurons. These studies demonstrated a premature generation of layer 5 cortical neurons. In addition, both the total number and percentage of progenitor cells proliferating in the ventricular zone were markedly reduced in the CPT II case in comparison to a reference case. Our results indicate that CPT II deficiency alters the normal program of cellular proliferation and differentiation in the cortex, with early differentiation of progenitor cells associated with premature cortical maturation.

  18. Fibroblast proliferation alters cardiac excitation conduction and contraction: a computational study*

    OpenAIRE

    Zhan, He-qing; Xia, Ling; Shou, Guo-fa; Zang, Yun-liang; Liu, Feng; Crozier, Stuart

    2014-01-01

    In this study, the effects of cardiac fibroblast proliferation on cardiac electric excitation conduction and mechanical contraction were investigated using a proposed integrated myocardial-fibroblastic electromechanical model. At the cellular level, models of the human ventricular myocyte and fibroblast were modified to incorporate a model of cardiac mechanical contraction and cooperativity mechanisms. Cellular electromechanical coupling was realized with a calcium buffer. At the tissue level...

  19. Integrated cellular systems

    Science.gov (United States)

    Harper, Jason C.

    The generation of new three-dimensional (3D) matrices that enable integration of biomolecular components and whole cells into device architectures, without adversely altering their morphology or activity, continues to be an expanding and challenging field of research. This research is driven by the promise that encapsulated biomolecules and cells can significantly impact areas as diverse as biocatalysis, controlled delivery of therapeutics, environmental and industrial process monitoring, early warning of warfare agents, bioelectronics, photonics, smart prosthetics, advanced physiological sensors, portable medical diagnostic devices, and tissue/organ replacement. This work focuses on the development of a fundamental understanding of the biochemical and nanomaterial mechanisms that govern the cell directed assembly and integration process. It was shown that this integration process relies on the ability of cells to actively develop a pH gradient in response to evaporation induced osmotic stress, which catalyzes silica condensation within a thin 3D volume surrounding the cells, creating a functional bio/nano interface. The mechanism responsible for introducing functional foreign membrane-bound proteins via proteoliposome addition to the silica-lipid-cell matrix was also determined. Utilizing this new understanding, 3D cellular immobilization capabilities were extended using sol-gel matrices endowed with glycerol, trehalose, and media components. The effects of these additives, and the metabolic phase of encapsulated S. cerivisiase cells, on long-term viability and the rate of inducible gene expression was studied. This enabled the entrapment of cells within a novel microfluidic platform capable of simultaneous colorimetric, fluorescent, and electrochemical detection of a single analyte, significantly improving confidence in the biosensor output. As a complementary approach, multiphoton protein lithography was utilized to engineer 3D protein matrices in which to

  20. Effects of Radiation on Cellular Proliferation and Differentiation. Proceedings of a Symposium on the Effects of Radiation on Cellular Proliferation and Differentiation

    International Nuclear Information System (INIS)

    Proceedings of a Symposium organized by the IAEA in co-operation with the Joint Commission on Applied Radioactivity and held in Monaco, 1-5 April 1968. Over 100 scientists from 20 countries and two international organizations attended the meeting. Contents: Introductory address; Biochemical considerations of injury and repair; Haemopoietic stem cells: relationships and kinetics; Haemopoiesis: growth and differentiation; Lymphopoiesis and the immune response; Proliferative response of other mammalian systems: tumour cells and intestinal cells. Each paper is in its original language (36 English, 3 French and 1 Russian) and is preceded by an abstract in English, with a second one in the original language if this is not English. (author)

  1. Tamper indicating packaging

    International Nuclear Information System (INIS)

    Protecting sensitive items from undetected tampering in an unattended environment is crucial to the success of non-proliferation efforts relying on the verification of critical activities. Tamper Indicating Packaging (TIP) technologies are applied to containers, packages, and equipment that require an indication of a tamper attempt. Examples include: the transportation and storage of nuclear material, the operation and shipment of surveillance equipment and monitoring sensors, and the retail storage of medicine and food products. The spectrum of adversarial tampering ranges from attempted concealment of a pin-hole sized penetration to the complete container replacement, which would involve counterfeiting efforts of various degrees. Sandia National Laboratories (SNL) has developed a technology base for advanced TIP materials, sensors, designs, and processes which can be adapted to various future monitoring systems. The purpose of this technology base is to investigate potential new technologies, and to perform basic research of advanced technologies. This paper will describe the theory of TIP technologies and recent investigations of TIP technologies at SNL

  2. Multiuser Cellular Network

    CERN Document Server

    Bao, Yi; Chen, Ming

    2011-01-01

    Modern radio communication is faced with a problem about how to distribute restricted frequency to users in a certain space. Since our task is to minimize the number of repeaters, a natural idea is enlarging coverage area. However, coverage has restrictions. First, service area has to be divided economically as repeater's coverage is limited. In this paper, our fundamental method is to adopt seamless cellular network division. Second, underlying physics content in frequency distribution problem is interference between two close frequencies. Consequently, we choose a proper frequency width of 0.1MHz and a relevantly reliable setting to apply one frequency several times. We make a few general assumptions to simplify real situation. For instance, immobile users yield to homogenous distribution; repeaters can receive and transmit information in any given frequency in duplex operation; coverage is mainly decided by antenna height. Two models are built up to solve 1000 users and 10000 users situations respectively....

  3. Engineering Cellular Metabolism

    DEFF Research Database (Denmark)

    Nielsen, Jens; Keasling, Jay

    2016-01-01

    Metabolic engineering is the science of rewiring the metabolism of cells to enhance production of native metabolites or to endow cells with the ability to produce new products. The potential applications of such efforts are wide ranging, including the generation of fuels, chemicals, foods, feeds......, and pharmaceuticals. However, making cells into efficient factories is challenging because cells have evolved robust metabolic networks with hard-wired, tightly regulated lines of communication between molecular pathways that resist efforts to divert resources. Here, we will review the current status and challenges...... of metabolic engineering and will discuss how new technologies can enable metabolic engineering to be scaled up to the industrial level, either by cutting off the lines of control for endogenous metabolism or by infiltrating the system with disruptive, heterologous pathways that overcome cellular regulation....

  4. Modeling In Vitro Cellular Responses to Silver Nanoparticles

    Directory of Open Access Journals (Sweden)

    Dwaipayan Mukherjee

    2014-01-01

    Full Text Available Engineered nanoparticles (NPs have been widely demonstrated to induce toxic effects to various cell types. In vitro cell exposure systems have high potential for reliable, high throughput screening of nanoparticle toxicity, allowing focusing on particular pathways while excluding unwanted effects due to other cells or tissue dosimetry. The work presented here involves a detailed biologically based computational model of cellular interactions with NPs; it utilizes measurements performed in human cell culture systems in vitro, to develop a mechanistic mathematical model that can support analysis and prediction of in vivo effects of NPs. The model considers basic cellular mechanisms including proliferation, apoptosis, and production of cytokines in response to NPs. This new model is implemented for macrophages and parameterized using in vitro measurements of changes in cellular viability and mRNA levels of cytokines: TNF, IL-1b, IL-6, IL-8, and IL-10. The model includes in vitro cellular dosimetry due to nanoparticle transport and transformation. Furthermore, the model developed here optimizes the essential cellular parameters based on in vitro measurements, and provides a “stepping stone” for the development of more advanced in vivo models that will incorporate additional cellular and NP interactions.

  5. Combinatorial approaches to evaluate nanodiamond uptake and induced cellular fate

    Science.gov (United States)

    Eldawud, Reem; Reitzig, Manuela; Opitz, Jörg; Rojansakul, Yon; Jiang, Wenjuan; Nangia, Shikha; Zoica Dinu, Cerasela

    2016-02-01

    Nanodiamonds (NDs) are an emerging class of engineered nanomaterials that hold great promise for the next generation of bionanotechnological products to be used for drug and gene delivery, or for bio-imaging and biosensing. Previous studies have shown that upon their cellular uptake, NDs exhibit high biocompatibility in various in vitro and in vivo set-ups. Herein we hypothesized that the increased NDs biocompatibility is a result of minimum membrane perturbations and their reduced ability to induce disruption or damage during cellular translocation. Using multi-scale combinatorial approaches that simulate ND-membrane interactions, we correlated NDs real-time cellular uptake and kinetics with the ND-induced membrane fluctuations to derive energy requirements for the uptake to occur. Our discrete and real-time analyses showed that the majority of NDs internalization occurs within 2 h of cellular exposure, however, with no effects on cellular viability, proliferation or cellular behavior. Furthermore, our simulation analyses using coarse-grained models identified key changes in the energy profile, membrane deformation and recovery time, all functions of the average ND or ND-based agglomerate size. Understanding the mechanisms responsible for ND-cell membrane interactions could possibly advance their implementation in various biomedical applications.

  6. Cellular pressure and volume regulation and implications for cell mechanics.

    Science.gov (United States)

    Jiang, Hongyuan; Sun, Sean X

    2013-08-01

    In eukaryotic cells, small changes in cell volume can serve as important signals for cell proliferation, death, and migration. Volume and shape regulation also directly impacts the mechanics of cells and tissues. Here, we develop a mathematical model of cellular volume and pressure regulation, incorporating essential elements such as water permeation, mechanosensitive channels, active ion pumps, and active stresses in the cortex. The model can fully explain recent experimental data, and it predicts cellular volume and pressure for several models of cell cortical mechanics. Moreover, we show that when cells are subjected to an externally applied load, such as in an atomic force microscopy indentation experiment, active regulation of volume and pressure leads to a complex cellular response. Instead of the passive mechanics of the cortex, the observed cell stiffness depends on several factors working together. This provides a mathematical explanation of rate-dependent response of cells under force. PMID:23931309

  7. Cellular events and biomarkers of wound healing

    Directory of Open Access Journals (Sweden)

    Shah Jumaat Mohd. Yussof

    2012-01-01

    Full Text Available Researchers have identified several of the cellular events associated with wound healing. Platelets, neutrophils, macrophages, and fibroblasts primarily contribute to the process. They release cytokines including interleukins (ILs and TNF-α, and growth factors, of which platelet-derived growth factor (PDGF is perhaps the most important. The cytokines and growth factors manipulate the inflammatory phase of healing. Cytokines are chemotactic for white cells and fibroblasts, while the growth factors initiate fibroblast and keratinocyte proliferation. Inflammation is followed by the proliferation of fibroblasts, which lay down the extracellular matrix. Simultaneously, various white cells and other connective tissue cells release both the matrix metalloproteinases (MMPs and the tissue inhibitors of these metalloproteinases (TIMPs. MMPs remove damaged structural proteins such as collagen, while the fibroblasts lay down fresh extracellular matrix proteins. Fluid collected from acute, healing wounds contains growth factors, and stimulates fibroblast proliferation, but fluid collected from chronic, nonhealing wounds does not. Fibroblasts from chronic wounds do not respond to chronic wound fluid, probably because the fibroblasts of these wounds have lost the receptors that respond to cytokines and growth factors. Nonhealing wounds contain high levels of IL1, IL6, and MMPs, and an abnormally high MMP/TIMP ratio. Clinical examination of wounds inconsistently predicts which wounds will heal when procedures like secondary closure are planned. Surgeons therefore hope that these chemicals can be used as biomarkers of wounds which have impaired ability to heal. There is also evidence that the application of growth factors like PDGF will help the healing of chronic, nonhealing wounds.

  8. The intracellular mechanism of alpha-fetoprotein promoting the proliferation of NIH 3T3 cells

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    AIM The existence and properties of alpha-fetoprotein (AFP) receptor on the surface of NIH 3T3 cells and the effects of AFP on cellular signal transduction pathway were investigated. METHODS The effect of AFP on the proliferation of NIH 3T3 cells was measured by incorporation of 3H-TdR. Receptor-binding assay of 125I-AFP was performed to detect the properties of AFP receptor in NIH 3T3 cells. The influences of AFP on the [cAMP]i and the activities of protein kinase A (PKA) were determined. Western blot was used to detect the change of K-ras P21 protein expression. RESULTS The proliferation of NIH 3T3 cells treated with 0-80 mg/L of AFP was significantly enhanced. The Scatchard analysis indicated that there were two classes of binding sites with KD of 2.722×10-9M (Bmax=12810 sites per cell) and 8.931× 10-SM (Bmax=l19700 sites per cell) respectively. In the presence of AFP (20 mg/L), the content of cAMP and activities of PKA were significantly elevated . The level of K-ras P21 protein was upregulated by AFP at the concentration of 20 mg/L. The monoclonal antibody against AFP could reverse the effects of AFP on the cAMP content, PKA activity and the expression of K-ras p21 gene. CONCLUSION The effect of AFP on the cell proliferation was achieved by binding its receptor to trigger the signal transduction pathway of cAMP-PKA and alter the expression of K- ras p21 gene.

  9. Advancing nanograined/ultrafine-grained structures for metal implant technology: Interplay between grooving of nano/ultrafine grains and cellular response

    International Nuclear Information System (INIS)

    Nanograined/ultrafine-grained (NG/UFG) metals provide surfaces that are different from conventional coarse-grained polycrystalline metals because of the high fraction of grain boundaries. In the context of osseointegration of metal implants, grooving of nanograins/ultrafine grains by electrochemical grooving is a potential approach to increase the biomechanical interlocking and anchorage with consequent enhancement of cellular response. The primary objective of the research described here is to advance science and technology of metal implants by making a relative comparison of osteoblast response of grain boundary grooved and planar NG/UFG surfaces. The NG/UFG substrates were obtained using an ingenious concept of controlled phase reversion and the grain boundaries were electrochemically treated to induce grooving of large fraction of grain boundaries of NG/UFG substrate. Experiments on the effect of grooving of grain boundaries of NG/UFG metal indicated that cell attachment, proliferation, viability, morphology, and spread are favorably modulated and significantly different from planar (non-grooved) NG/UFG substrates. Furthermore, immunofluorescence studies demonstrated stronger vinculin signals associated with actin stress fibers in the outer regions of the cells and cellular extensions on electrochemically grooved NG/UFG substrate. These observations are indicative of accelerated response of cell-substrate interaction and activity. The differences in the cellular response of planar and grain boundary grooved NG/UFG surface are attributed to favorable surface topography that accelerates the cellular activity.

  10. Advancing nanograined/ultrafine-grained structures for metal implant technology: Interplay between grooving of nano/ultrafine grains and cellular response

    Energy Technology Data Exchange (ETDEWEB)

    Venkatsurya, P.K.C; Thein-Han, W.W. [Biomaterials and Biomedical Engineering Research Laboratory, Center for Structural and Functional Materials, University of Louisiana at Lafayette, P.O. Box 44130, Lafayette, LA 70504 (United States); Misra, R.D.K., E-mail: dmisra@louisiana.edu [Biomaterials and Biomedical Engineering Research Laboratory, Center for Structural and Functional Materials, University of Louisiana at Lafayette, P.O. Box 44130, Lafayette, LA 70504 (United States); Somani, M.C.; Karjalainen, L.P. [Department of Mechanical Engineering, University of Oulu, P.O. Box 4200, 90014 Oulu (Finland)

    2010-08-30

    Nanograined/ultrafine-grained (NG/UFG) metals provide surfaces that are different from conventional coarse-grained polycrystalline metals because of the high fraction of grain boundaries. In the context of osseointegration of metal implants, grooving of nanograins/ultrafine grains by electrochemical grooving is a potential approach to increase the biomechanical interlocking and anchorage with consequent enhancement of cellular response. The primary objective of the research described here is to advance science and technology of metal implants by making a relative comparison of osteoblast response of grain boundary grooved and planar NG/UFG surfaces. The NG/UFG substrates were obtained using an ingenious concept of controlled phase reversion and the grain boundaries were electrochemically treated to induce grooving of large fraction of grain boundaries of NG/UFG substrate. Experiments on the effect of grooving of grain boundaries of NG/UFG metal indicated that cell attachment, proliferation, viability, morphology, and spread are favorably modulated and significantly different from planar (non-grooved) NG/UFG substrates. Furthermore, immunofluorescence studies demonstrated stronger vinculin signals associated with actin stress fibers in the outer regions of the cells and cellular extensions on electrochemically grooved NG/UFG substrate. These observations are indicative of accelerated response of cell-substrate interaction and activity. The differences in the cellular response of planar and grain boundary grooved NG/UFG surface are attributed to favorable surface topography that accelerates the cellular activity.

  11. Building mathematics cellular phone learning communities

    Directory of Open Access Journals (Sweden)

    Wajeeh M. Daher

    2011-04-01

    Full Text Available Researchers emphasize the importance of maintaining learning communities and environments. This article describes the building and nourishment of a learning community, one comprised of middle school students who learned mathematics out-of-class using the cellular phone. The building of the learning community was led by three third year pre-service teachers majoring in mathematics and computers. The pre-service teachers selected thirty 8th grade students to learn mathematics with the cellular phone and be part of a learning community experimenting with this learning. To analyze the building and development stages of the cellular phone learning community, two models of community building stages were used; first the team development model developed by Tuckman (1965, second the life cycle model of a virtual learning community developed by Garber (2004. The research findings indicate that a learning community which is centered on a new technology has five 'life' phases of development: Pre-birth, birth, formation, performing, and maturity. Further, the research finding indicate that the norms that were encouraged by the preservice teachers who initiated the cellular phone learning community resulted in a community which developed, nourished and matured to be similar to a community of experienced applied mathematicians who use mathematical formulae to study everyday phenomena.

  12. Cellular contractility requires ubiquitin mediated proteolysis.

    Directory of Open Access Journals (Sweden)

    Yuval Cinnamon

    Full Text Available BACKGROUND: Cellular contractility, essential for cell movement and proliferation, is regulated by microtubules, RhoA and actomyosin. The RhoA dependent kinase ROCK ensures the phosphorylation of the regulatory Myosin II Light Chain (MLC Ser19, thereby activating actomyosin contractions. Microtubules are upstream inhibitors of contractility and their depolymerization or depletion cause cells to contract by activating RhoA. How microtubule dynamics regulates RhoA remains, a major missing link in understanding contractility. PRINCIPAL FINDINGS: We observed that contractility is inhibited by microtubules not only, as previously reported, in adherent cells, but also in non-adhering interphase and mitotic cells. Strikingly we observed that contractility requires ubiquitin mediated proteolysis by a Cullin-RING ubiquitin ligase. Inhibition of proteolysis, ubiquitination and neddylation all led to complete cessation of contractility and considerably reduced MLC Ser19 phosphorylation. CONCLUSIONS: Our results imply that cells express a contractility inhibitor that is degraded by ubiquitin mediated proteolysis, either constitutively or in response to microtubule depolymerization. This degradation seems to depend on a Cullin-RING ubiquitin ligase and is required for cellular contractions.

  13. A new description of cellular quiescence.

    Directory of Open Access Journals (Sweden)

    Hilary A Coller

    2006-03-01

    Full Text Available Cellular quiescence, defined as reversible growth/proliferation arrest, is thought to represent a homogenous state induced by diverse anti-mitogenic signals. We used transcriptional profiling to characterize human diploid fibroblasts that exited the cell cycle after exposure to three independent signals--mitogen withdrawal, contact inhibition, and loss of adhesion. We show here that each signal caused regulation of a unique set of genes known to be important for cessation of growth and division. Therefore, contrary to expectation, cells enter different quiescent states that are determined by the initiating signal. However, underlying this diversity we discovered a set of genes whose specific expression in non-dividing cells was signal-independent, and therefore representative of quiescence per se, rather than the signal that induced it. This fibroblast "quiescence program" contained genes that enforced the non-dividing state, and ensured the reversibility of the cell cycle arrest. We further demonstrate that one mechanism by which the reversibility of quiescence is insured is the suppression of terminal differentiation. Expression of the quiescence program was not simply a downstream consequence of exit from the cell cycle, because key parts, including those involved in suppressing differentiation, were not recapitulated during the cell cycle arrest caused by direct inhibition of cyclin-dependent kinases. These studies form a basis for understanding the normal biology of cellular quiescence.

  14. The relationship between cellular adhesion and surface roughness for polyurethane modified by microwave plasma radiation

    Directory of Open Access Journals (Sweden)

    Heidari S

    2011-04-01

    Full Text Available Saeed Heidari Keshel1, S Neda Kh Azhdadi2, Azadeh Asefnezhad2, Mohammad Sadraeian3, Mohamad Montazeri4, Esmaeil Biazar51Stem Cell Preparation Unit, Eye Research Center, Farabi Eye Hospital, Tehran University of Medical Sciences; 2Department of Biomaterial Engineering, Faculty of Biomedical Engineering, Science and Research Branch - Islamic Azad University; 3Young Researchers Club, Islamic Azad University, North Tehran Branch, Tehran; 4Faculty of Medical Sciences, Babol University of Medical Sciences, Babol; 5Department of Chemistry, Islamic Azad University, Tonekabon, IranAbstract: Surface modification of medical polymers is carried out to improve biocompatibility. In this study, conventional polyurethane was exposed to microwave plasma treatment with oxygen and argon gases for 30 seconds and 60 seconds. Attenuated total reflection Fourier transform infrared spectra investigations of irradiated samples indicated the presence of functional groups. Atomic force microscope images of samples irradiated with inert and active gases indicated the nanometric topography of the sample surfaces. Samples irradiated by oxygen plasma indicated high roughness compared with those irradiated by inert plasma for the different lengths of time. In addition, surface roughness increased with time, which can be due to a reduction of contact angle of samples irradiated by oxygen plasma. Contact angle analysis indicated a reduction in samples irradiated with both types of plasma. However, samples irradiated with oxygen plasma indicated lower contact angle compared with those irradiated by argon plasma. Cellular investigations with unrestricted somatic stem cells showed better adhesion, cell growth, and proliferation among samples radiated by oxygen plasma for longer than for normal samples.Keywords: surface topography, polyurethane, plasma treatment, cellular investigation

  15. Emerging nuclear energy systems and nuclear weapon proliferation

    International Nuclear Information System (INIS)

    Generally when considering problems of proliferation of nuclear weapons, discussions are focused on horizontal proliferation. However, the emerging nuclear energy systems currently have an impact mainly on vertical proliferation. The paper indicates that technologies connected with emerging nuclear energy systems, such as fusion reactors and accelerators, enhance the knowledge of thermonuclear weapon physics and will enable production of military useful nuclear materials (including some rare elements). At present such technologies are enhancing the arsenal of the nuclear weapon states. But one should not forget the future implications for horizontal proliferation of nuclear weapons as some of the techniques will in the near future be within the technological and economic capabilities of non-nuclear weapon states. Some of these systems are not under any international control. (orig.)

  16. Good news, bad news on proliferation

    International Nuclear Information System (INIS)

    While Argentina and Brazil now seem less likely to acquire nuclear weapons, Indian and Pakistani intentions remain uncertain. The Israeli nuclear program and recent allegations of black-marketing are even more disturbing. The author notes the positive developments in Latin America and some hopeful signs in South Asia, despite uncertainties over their final outcome. He finds Israel's program the most disturbing because of the deployment of Jericho II missiles and indications that Israel possesses a fully militarized nuclear force which was developed by illegal means. These activities could politicize the Non-Proliferation Treaty review conference. 14 references

  17. Molecular and cellular mechanisms of cadmium carcinogenesis

    International Nuclear Information System (INIS)

    Cadmium is a heavy metal, which is widely used in industry, affecting human health through occupational and environmental exposure. In mammals, it exerts multiple toxic effects and has been classified as a human carcinogen by the International Agency for Research on Cancer. Cadmium affects cell proliferation, differentiation, apoptosis and other cellular activities. Cd2+ does not catalyze Fenton-type reactions because it does not accept or donate electrons under physiological conditions, and it is only weakly genotoxic. Hence, indirect mechanisms are implicated in the carcinogenicity of cadmium. In this review multiple mechanisms are discussed, such as modulation of gene expression and signal transduction, interference with enzymes of the cellular antioxidant system and generation of reactive oxygen species (ROS), inhibition of DNA repair and DNA methylation, role in apoptosis and disruption of E-cadherin-mediated cell-cell adhesion. Cadmium affects both gene transcription and translation. The major mechanisms of gene induction by cadmium known so far are modulation of cellular signal transduction pathways by enhancement of protein phosphorylation and activation of transcription and translation factors. Cadmium interferes with antioxidant defense mechanisms and stimulates the production of reactive oxygen species, which may act as signaling molecules in the induction of gene expression and apoptosis. The inhibition of DNA repair processes by cadmium represents a mechanism by which cadmium enhances the genotoxicity of other agents and may contribute to the tumor initiation by this metal. The disruption of E-cadherin-mediated cell-cell adhesion by cadmium probably further stimulates the development of tumors. It becomes clear that there exist multiple mechanisms which contribute to the carcinogenicity of cadmium, although the relative weights of these contributions are difficult to estimate

  18. The State of Cellular Probes

    OpenAIRE

    Yim, Youngbin

    2003-01-01

    Cellular probe technology is one of several potentially promising technologies for obtaining accurate travel time information. In 1996, the Federal Communications Commission (FCC) mandated E911 requirements that cellular location be provided when 911 emergency calls come in to emergency management authorities. The E911 requirements allow 50 -300 meters from the emergency call location, depending on the type of cellular phone technology used and whether handset-based or network-based solutions...

  19. Never-ageing cellular senescence

    OpenAIRE

    Ogrunc, Müge; d’Adda di Fagagna, Fabrizio

    2011-01-01

    Cellular senescence was historically discovered as a form of cellular ageing of in vitro cultured cells. It has been under the spotlight following the evidence of oncogene-induced senescence in vivo and its role as a potent tumour suppressor mechanism. Presently, a PubMed search using keywords ‘cellular senescence and cancer’ reveals 8398 number of references (by April 2011) showing that while our knowledge of senescence keeps expanding, the complexity of the phenomenon keeps us – researchers...

  20. Ibrutinib inhibits BCR and NF-κB signaling and reduces tumor proliferation in tissue-resident cells of patients with CLL

    OpenAIRE

    Herman, Sarah E. M.; Mustafa, Rashida Z.; Gyamfi, Jennifer A.; Pittaluga, Stefania; Chang, Stella; Chang, Betty; Farooqui, Mohammed; Wiestner, Adrian

    2014-01-01

    Ibrutinib inhibits both BCR and NF-κB signaling in lymph node and bone marrow resident CLL cells.Rapid and sustained reduction of cellular activation and tumor proliferation was achieved in all anatomic compartments.

  1. Oxidative stress-induced proteome alterations target different cellular pathways in human myoblasts

    DEFF Research Database (Denmark)

    Baraibar, Martin A; Hyzewicz, Janek; Rogowska-Wrzesinska, Adelina;

    2011-01-01

    Although increased oxidative stress has been associated with the impairment of proliferation and function of adult human muscle stem cells, proteins either involved in the stress response or damaged by oxidation have not been identified. A parallel proteomics approach was performed for analyzing...... are mainly cytosolic and involved in carbohydrate metabolism, cellular assembly, cellular homeostasis, and protein synthesis and degradation. Pathway analysis revealed skeletal and muscular disorders, cell death, and cancer-related as the main molecular networks altered. Interestingly, these pathways...

  2. Both Complexity and Location of DNA Damage Contribute to Cellular Senescence Induced by Ionizing Radiation

    OpenAIRE

    Xurui Zhang; Caiyong Ye; Fang Sun; Wenjun Wei; Burong Hu; Jufang Wang

    2016-01-01

    Persistent DNA damage is considered as a main cause of cellular senescence induced by ionizing radiation. However, the molecular bases of the DNA damage and their contribution to cellular senescence are not completely clear. In this study, we found that both heavy ions and X-rays induced senescence in human uveal melanoma 92-1 cells. By measuring senescence associated-β-galactosidase and cell proliferation, we identified that heavy ions were more effective at inducing senescence than X-rays. ...

  3. Nuclear proliferation and safeguards. Summary

    International Nuclear Information System (INIS)

    This comprehensive analysis of the technological, economic, and political factors affecting the potential spread of nuclear weapons proved useful in the congressional debate which culminated in the Nuclear Non-Proliferation Act of 1978. The report was subsequently published commercially and has been a frequently cited reference in the literature on proliferation and nuclear power. Despite developments since 1977, the information in the OTA report is still useful to those wishing to obtain an indepth understanding of the issues. Included is an analysis of why a nation might want nuclear weapons development program and the various sources of nuclear material are discussed. The control of proliferation is considered as well as its relation to the nuclear industry

  4. Gold Nanoparticles Promote Proliferation of Human Periodontal Ligament Stem Cells and Have Limited Effects on Cells Differentiation

    Directory of Open Access Journals (Sweden)

    Chen Li

    2016-01-01

    Full Text Available Gold nanoparticles (AuNPs had been widely applied in the practice and advancement of chemistry, biology, and medicine due to facility of synthesis and versatility in surface functionalization. Recent studies had shown that AuNPs can be applied to cells, affecting cellular physiological processes such as proliferation and differentiation. In this study, four diameters of AuNPs (20, 40, 60, and 80 nm were cocultured with human periodontal ligament cells (hPDLCs at six different concentrations. The optimal size and concentration of AuNPs were selected to treat human periodontal ligament stem cells (hPDLSCs to evaluate proliferation. Moreover, the influence of AuNPs on multiple differentiation capacity of hPDLSCs was clarified. The results revealed that AuNPs (60 nm, 56 μM can effectively promote the proliferation of hPDLCs/hPDLSCs in vitro, slightly enhance osteoblastic differentiation, and have no effect on adipogenic differentiation. In addition, the expression of COL-1, Runx2, BSP, and OCN was upregulated in the presence of AuNPs (60 nm, 56 μM. These results indicated that AuNPs (60 nm, 56 μM can effectively promote the proliferation of hPDLCs/hPDLSCs and have no significant effect on the differentiation of hPDLSCs. These results provide an insight on the advantage of implementing of AuNPs on hPDLSCs culture and expose the influence of these materials on periodontal tissue engineering.

  5. A Modified Sensitive Driving Cellular Automaton Model

    Institute of Scientific and Technical Information of China (English)

    GE Hong-Xia; DAI Shi-Qiang; DONG Li-Yun; LEI Li

    2005-01-01

    A modified cellular automaton model for traffic flow on highway is proposed with a novel concept about the variable security gap. The concept is first introduced into the original Nagel-Schreckenberg model, which is called the non-sensitive driving cellular automaton model. And then it is incorporated with a sensitive driving NaSch model,in which the randomization brake is arranged before the deterministic deceleration. A parameter related to the variable security gap is determined through simulation. Comparison of the simulation results indicates that the variable security gap has different influence on the two models. The fundamental diagram obtained by simulation with the modified sensitive driving NaSch model shows that the maximumflow are in good agreement with the observed data, indicating that the presented model is more reasonable and realistic.

  6. Simulated Hypergravity Alters Vascular Smooth Muscle Cell Proliferation and Motility

    Science.gov (United States)

    Hunt, Shameka; Bettis, Barika; Harris-Hooker, Sandra; Sanford, Gary L.

    1997-01-01

    The cellular effects of gravity are poorly understood due to its constancy and nonavailability of altered gravitational models. Such an understanding is crucial for prolonged space flights. In these studies, we assessed the influence of centrifugation at 6G (HGrav) on vascular smooth muscle (SMC) mobility and proliferation. Cells were: (a) plated at low density and subjected to HGrav for 24-72 hr for proliferation studies, or (b) grown to confluency, subjected to HGrav, mechanically denuded and monitored for cell movement into the denuded area. Controls were maintained under normogravity. SMC showed a 50% inhibition of growth under HGrav and 10% serum; HGrav and low serum resulted in greater growth inhibition. The rate of movement of SMC into the denuded area was 2-3-fold higher under HGrav in low serum compared to controls, but similar in 10% serum. These studies show that HGrav has significant effects on SMC growth and mobility, which are dependent on serum levels.

  7. Cultural Diagnosis: An Empirical Investigation of Cellular Industry of Pakistan

    Directory of Open Access Journals (Sweden)

    Qamar Ali

    2011-11-01

    Full Text Available This study describes research in five cellular companies operating in Pakistan, aimed at identifying their current and preferred organizational culture. Using Quinn and Rohrbaugh (1983 competing values framework, the overall cultural profiles and dominant characteristics of the organizations and industry are determined through a personally administered survey employing the Organizational Culture Assessment Instrument (OCAI. The results indicate that hierarchy culture is dominating in cellular industry, whereas the clan is found to be the most preferred cultural archetype in majority of cellular companies. This indicates a misalignment between what employees think is needed and what is perceived to exist.

  8. Proliferation aspects of plutonium recycling

    International Nuclear Information System (INIS)

    Plutonium recycling offers benefits in an energy perspective of sustainable development, and, moreover it contributes to non-proliferation. Prior to recycling, reactor-grade plutonium from light-water reactors does not lend itself easily to the assembly of explosive nuclear devices; thereafter, practically not at all. Control systems for material security and non-proliferation should identify and adopt several categories of plutonium covering various isotopic mixtures associated with different fuel types, in order to better reflect the risks and to better focus their controls. The author proposes the adoption of three categories of plutonium. (author)

  9. 47 CFR 22.909 - Cellular markets.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false Cellular markets. 22.909 Section 22.909... Cellular Radiotelephone Service § 22.909 Cellular markets. Cellular markets are standard geographic areas used by the FCC for administrative convenience in the licensing of cellular systems. Cellular...

  10. Cellular Automata Studies of Vertical Silicon Devices

    OpenAIRE

    M. Saraniti; G. Zandler; G. Formicone; S. Goodnick

    1998-01-01

    We present systematic theoretical Cellular Automata (CA) studies of a novel nanometer scale Si device, namely vertically grown Metal Oxide Field Effect Transistors (MOSFET) with channel lengths between 65 and 120 nm. The CA simulations predict drain characteristics and output conductance as a function of gate length. The excellent agreement with available experimental data indicates a high quality oxide/semiconductor interface. Impact ionization is shown to be of minor importance. For inhomog...

  11. Cellular and Developmental Biology of TRPM7 Channel-Kinase: Implicated Roles in Cancer

    Directory of Open Access Journals (Sweden)

    Nelson S. Yee

    2014-07-01

    Full Text Available The transient receptor potential melastatin-subfamily member 7 (TRPM7 is a ubiquitously expressed cation-permeable ion channel with intrinsic kinase activity that plays important roles in various physiological functions. Biochemical and electrophysiological studies, in combination with molecular analyses of TRPM7, have generated insights into its functions as a cellular sensor and transducer of physicochemical stimuli. Accumulating evidence indicates that TRPM7 channel-kinase is essential for cellular processes, such as proliferation, survival, differentiation, growth, and migration. Experimental studies in model organisms, such as zebrafish, mouse, and frog, have begun to elucidate the pleiotropic roles of TRPM7 during embryonic development from gastrulation to organogenesis. Aberrant expression and/or activity of the TRPM7 channel-kinase have been implicated in human diseases including a variety of cancer. Studying the functional roles of TRPM7 and the underlying mechanisms in normal cells and developmental processes is expected to help understand how TRPM7 channel-kinase contributes to pathogenesis, such as malignant neoplasia. On the other hand, studies of TRPM7 in diseases, particularly cancer, will help shed new light in the normal functions of TRPM7 under physiological conditions. In this article, we will provide an updated review of the structural features and biological functions of TRPM7, present a summary of current knowledge of its roles in development and cancer, and discuss the potential of TRPM7 as a clinical biomarker and therapeutic target in malignant diseases.

  12. TNF and TNF Receptor Superfamily Members in HIV infection: New Cellular Targets for Therapy?

    Directory of Open Access Journals (Sweden)

    Amit Kumar

    2013-01-01

    Full Text Available Tumor necrosis factor (TNF and TNF receptors (TNFR superfamily members are engaged in diverse cellular phenomena such as cellular proliferation, morphogenesis, apoptosis, inflammation, and immune regulation. Their role in regulating viral infections has been well documented. Viruses have evolved with numerous strategies to interfere with TNF-mediated signaling indicating the importance of TNF and TNFR superfamily in viral pathogenesis. Recent research reports suggest that TNF and TNFRs play an important role in the pathogenesis of HIV. TNFR signaling modulates HIV replication and HIV proteins interfere with TNF/TNFR pathways. Since immune activation and inflammation are the hallmark of HIV infection, the use of TNF inhibitors can have significant impact on HIV disease progression. In this review, we will describe how HIV infection is modulated by signaling mediated through members of TNF and TNFR superfamily and in turn how these latter could be targeted by HIV proteins. Finally, we will discuss the emerging therapeutics options based on modulation of TNF activity that could ultimately lead to the cure of HIV-infected patients.

  13. Distinctive behavioral and cellular responses to fluoxetine in the mouse model for Fragile X syndrome

    Directory of Open Access Journals (Sweden)

    Marko eUutela

    2014-05-01

    Full Text Available Fluoxetine is used as a therapeutic agent for autism spectrum disorder (ASD, including Fragile X syndrome (FXS. The treatment often associates with disruptive behaviors such as agitation and disinhibited behaviors in FXS. To identify mechanisms that increase the risk to poor treatment outcome, we investigated the behavioral and cellular effects of fluoxetine on adult Fmr1 knockout (KO mice, a mouse model for FXS. We found that fluoxetine reduced anxiety-like behavior of both wild type and Fmr1 KO mice seen as shortened latency to enter the center area in the open field test. In Fmr1 KO mice, fluoxetine normalized locomotor hyperactivity but abnormally increased exploratory activity. Reduced Brain-derived neurotrophic factor (BDNF and increased TrkB receptor expression levels in the hippocampus of Fmr1 KO mice associated with inappropriate coping responses under stressful condition and abolished antidepressant activity of fluoxetine. Fluoxetine response in the cell proliferation was also missing in the hippocampus of Fmr1 KO mice when compared with wild type controls. The postnatal expression of serotonin transporter was reduced in the thalamic nuclei of Fmr1 KO mice during the time of transient innervation of somatosensory neurons suggesting that developmental changes of serotonin transporter (SERT expression were involved in the differential cellular and behavioral responses to fluoxetine in wild type and Fmr1 mice. The results indicate that changes of BDNF/TrkB signaling contribute to differential behavioral responses to fluoxetine among individuals with ASD.

  14. Wolbachia-mediated resistance to dengue virus infection and death at the cellular level.

    Directory of Open Access Journals (Sweden)

    Francesca D Frentiu

    Full Text Available BACKGROUND: Dengue is currently the most important arthropod-borne viral disease of humans. Recent work has shown dengue virus displays limited replication in its primary vector, the mosquito Aedes aegypti, when the insect harbors the endosymbiotic bacterium Wolbachia pipientis. Wolbachia-mediated inhibition of virus replication may lead to novel methods of arboviral control, yet the functional and cellular mechanisms that underpin it are unknown. METHODOLOGY/PRINCIPAL FINDINGS: Using paired Wolbachia-infected and uninfected Aedes-derived cell lines and dengue virus, we confirm the phenomenon of viral inhibition at the cellular level. Although Wolbachia imposes a fitness cost to cells via reduced proliferation, it also provides a significant degree of protection from virus-induced mortality. The extent of viral inhibition is related to the density of Wolbachia per cell, with highly infected cell lines showing almost complete protection from dengue infection and dramatically reduced virus titers compared to lines not infected with the bacteria. CONCLUSIONS/SIGNIFICANCE: We have shown that cells infected with Wolbachia display inhibition of dengue virus replication, that the extent of inhibition is related to bacterial density and that Wolbachia infection, although costly, will provide a fitness benefit in some circumstances. Our results parallel findings in mosquitoes and flies, indicating that cell line models will provide useful and experimentally tractable models to study the mechanisms underlying Wolbachia-mediated protection from viruses.

  15. Polycomb proteins control proliferation and transformation independently of cell cycle checkpoints by regulating DNA replication

    DEFF Research Database (Denmark)

    Piunti, Andrea; Rossi, Alessandra; Cerutti, Aurora;

    2014-01-01

    PRCs regulate cellular proliferation and transformation independently of the Ink4a/Arf-pRb-p53 pathway. We provide evidence that PRCs localize at replication forks, and that loss of their function directly affects the progression and symmetry of DNA replication forks. Thus, we have identified a novel...

  16. Ethylene Inhibits Cell Proliferation of the Arabidopsis Root Meristem.

    Science.gov (United States)

    Street, Ian H; Aman, Sitwat; Zubo, Yan; Ramzan, Aleena; Wang, Xiaomin; Shakeel, Samina N; Kieber, Joseph J; Schaller, G Eric

    2015-09-01

    The root system of plants plays a critical role in plant growth and survival, with root growth being dependent on both cell proliferation and cell elongation. Multiple phytohormones interact to control root growth, including ethylene, which is primarily known for its role in controlling root cell elongation. We find that ethylene also negatively regulates cell proliferation at the root meristem of Arabidopsis (Arabidopsis thaliana). Genetic analysis indicates that the inhibition of cell proliferation involves two pathways operating downstream of the ethylene receptors. The major pathway is the canonical ethylene signal transduction pathway that incorporates CONSTITUTIVE TRIPLE RESPONSE1, ETHYLENE INSENSITIVE2, and the ETHYLENE INSENSITIVE3 family of transcription factors. The secondary pathway is a phosphorelay based on genetic analysis of receptor histidine kinase activity and mutants involving the type B response regulators. Analysis of ethylene-dependent gene expression and genetic analysis supports SHORT HYPOCOTYL2, a repressor of auxin signaling, as one mediator of the ethylene response and furthermore, indicates that SHORT HYPOCOTYL2 is a point of convergence for both ethylene and cytokinin in negatively regulating cell proliferation. Additional analysis indicates that ethylene signaling contributes but is not required for cytokinin to inhibit activity of the root meristem. These results identify key elements, along with points of cross talk with cytokinin and auxin, by which ethylene negatively regulates cell proliferation at the root apical meristem. PMID:26149574

  17. Cell expansion of human articular chondrocytes on macroporous gelatine scaffolds-impact of microcarrier selection on cell proliferation

    Energy Technology Data Exchange (ETDEWEB)

    Pettersson, Sofia; Kratz, Gunnar [Laboratory for Reconstructive Plastic Surgery, Department of Clinical and Experimental Medicine, Linkoeping University, SE-581 85 Linkoeping (Sweden); Wetteroe, Jonas [Rheumatology/AIR, Department of Clinical and Experimental Medicine, Linkoeping University, SE-581 85 Linkoeping (Sweden); Tengvall, Pentti, E-mail: sofia.pettersson@liu.se [Institute of Clinical Sciences, Department of Biomaterials, The Sahlgrenska Academy at University of Gothenburg, SE-405 30 Gothenburg (Sweden)

    2011-12-15

    This study investigates human chondrocyte expansion on four macroporous gelatine microcarriers (CultiSpher) differing with respect to two manufacturing processes-the amount of emulsifier used during initial preparation and the gelatine cross-linking medium. Monolayer-expanded articular chondrocytes from three donors were seeded onto the microcarriers and cultured in spinner flask systems for a total of 15 days. Samples were extracted every other day to monitor cell viability and establish cell counts, which were analysed using analysis of variance and piecewise linear regression. Chondrocyte densities increased according to a linear pattern for all microcarriers, indicating an ongoing, though limited, cell proliferation. A strong chondrocyte donor effect was seen during the initial expansion phase. The final cell yield differed significantly between the microcarriers and our results indicate that manufacturing differences affected chondrocyte densities at this point. Remaining cells stained positive for chondrogenic markers SOX-9 and S-100 but extracellular matrix formation was modest to undetectable. In conclusion, the four gelatine microcarriers supported chondrocyte adhesion and proliferation over a two week period. The best yield was observed for microcarriers produced with low emulsifier content and cross-linked in water and acetone. These results add to the identification of optimal biomaterial parameters for specific cellular processes and populations.

  18. Loss of the Mammalian DREAM Complex Deregulates Chondrocyte Proliferation

    OpenAIRE

    Forristal, Chantal; Henley, Shauna A; MacDonald, James I.; Bush, Jason R.; Ort, Carley; Daniel T. Passos; Talluri, Srikanth; Ishak, Charles A.; Thwaites, Michael J.; Norley, Chris J.; Litovchick, Larisa; DeCaprio, James A.; DiMattia, Gabriel; Holdsworth, David W.; Beier, Frank

    2014-01-01

    Mammalian DREAM is a conserved protein complex that functions in cellular quiescence. DREAM contains an E2F, a retinoblastoma (RB)-family protein, and the MuvB core (LIN9, LIN37, LIN52, LIN54, and RBBP4). In mammals, MuvB can alternatively bind to BMYB to form a complex that promotes mitotic gene expression. Because BMYB-MuvB is essential for proliferation, loss-of-function approaches to study MuvB have generated limited insight into DREAM function. Here, we report a gene-targeted mouse model...

  19. Peripubertal ovariectomy provides long-term postponement of age-associated decline in thymic cellularity and T-cell output

    Directory of Open Access Journals (Sweden)

    Perišić Milica

    2009-01-01

    Full Text Available The present study was undertaken to reassess the recently challenged role of ovarian hormones in age-associated thymic involution. For this purpose, in eleven-month-old peripubertally ovariectomized (Ox rats we analyzed: i thymic weight and cellularity, ii size of CD4+CD8+ double-positive (DP thymocyte population, which is believed to correlate to the thymic capacity to export mature T cells, iii number of recent thymic emigrants (RTEs, and iv number of peripheral blood CD4+ and CD8+ lymphocytes. It was found that both thymic weight and cellularity were greater in Ox than in control rats. In addition, in Ox rats the numbers of DP thymocytes and both CD4+ and CD8+ RTEs, were significantly greater than in controls, indicating a more efficient generation of T cells in these rats. Furthermore, these findings, coupled with data indicating that the number of neither CD4+ nor CD8+ peripheral blood lymphocytes was affected by ovariectomy, most likely, suggest a reduced homeostatic proliferation of memory cells in Ox rats, i.e. broadening of TCR peripheral repertoire without changes in the overall number of T cells leading to a more efficient response to newly encountered antigens. The results indicate that the ovarian steroid deprivation from early peripubertal period leads to a long lasting postponement/alleviation of age-associated decline in T-cell mediated immune response.

  20. Nuclear non-Proliferation treaty

    International Nuclear Information System (INIS)

    The text of a speech is presented delivered by the State President of South Africa, Mr. F.W. de Klerk, to a joint session of Parliament on 24 March 1993, announcing developments relating to South Africa's nuclear capability and accession to the Treaty on the Non-Proliferation of Nuclear Weapons

  1. Nuclear Proliferation Technology Trends Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Zentner, Michael D.; Coles, Garill A.; Talbert, Robert J.

    2005-10-04

    A process is underway to develop mature, integrated methodologies to address nonproliferation issues. A variety of methodologies (both qualitative and quantitative) are being considered. All have one thing in common, a need for a consistent set of proliferation related data that can be used as a basis for application. One approach to providing a basis for predicting and evaluating future proliferation events is to understand past proliferation events, that is, the different paths that have actually been taken to acquire or attempt to acquire special nuclear material. In order to provide this information, this report describing previous material acquisition activities (obtained from open source material) has been prepared. This report describes how, based on an evaluation of historical trends in nuclear technology development, conclusions can be reached concerning: (1) The length of time it takes to acquire a technology; (2) The length of time it takes for production of special nuclear material to begin; and (3) The type of approaches taken for acquiring the technology. In addition to examining time constants, the report is intended to provide information that could be used to support the use of the different non-proliferation analysis methodologies. Accordingly, each section includes: (1) Technology description; (2) Technology origin; (3) Basic theory; (4) Important components/materials; (5) Technology development; (6) Technological difficulties involved in use; (7) Changes/improvements in technology; (8) Countries that have used/attempted to use the technology; (9) Technology Information; (10) Acquisition approaches; (11) Time constants for technology development; and (12) Required Concurrent Technologies.

  2. Clustering nuclear receptors in liver regeneration identifies candidate modulators of hepatocyte proliferation and hepatocarcinoma.

    Directory of Open Access Journals (Sweden)

    Michele Vacca

    Full Text Available BACKGROUND & AIMS: Liver regeneration (LR is a valuable model for studying mechanisms modulating hepatocyte proliferation. Nuclear receptors (NRs are key players in the control of cellular functions, being ideal modulators of hepatic proliferation and carcinogenesis. METHODS & RESULTS: We used a previously validated RT-qPCR platform to profile modifications in the expression of all 49 members of the NR superfamily in mouse liver during LR. Twenty-nine NR transcripts were significantly modified in their expression during LR, including fatty acid (peroxisome proliferator-activated receptors, PPARs and oxysterol (liver X receptors, Lxrs sensors, circadian masters RevErbα and RevErbβ, glucocorticoid receptor (Gr and constitutive androxane receptor (Car. In order to detect the NRs that better characterize proliferative status vs. proliferating liver, we used the novel Random Forest (RF analysis to selected a trio of down-regulated NRs (thyroid receptor alpha, Trα; farsenoid X receptor beta, Fxrβ; Pparδ as best discriminators of the proliferating status. To validate our approach, we further studied PPARδ role in modulating hepatic proliferation. We first confirmed the suppression of PPARδ both in LR and human hepatocellular carcinoma at protein level, and then demonstrated that PPARδ agonist GW501516 reduces the proliferative potential of hepatoma cells. CONCLUSIONS: Our data suggest that NR transcriptome is modulated in proliferating liver and is a source of biomarkers and bona fide pharmacological targets for the management of liver disease affecting hepatocyte proliferation.

  3. MIMO Communication for Cellular Networks

    CERN Document Server

    Huang, Howard; Venkatesan, Sivarama

    2012-01-01

    As the theoretical foundations of multiple-antenna techniques evolve and as these multiple-input multiple-output (MIMO) techniques become essential for providing high data rates in wireless systems, there is a growing need to understand the performance limits of MIMO in practical networks. To address this need, MIMO Communication for Cellular Networks presents a systematic description of MIMO technology classes and a framework for MIMO system design that takes into account the essential physical-layer features of practical cellular networks. In contrast to works that focus on the theoretical performance of abstract MIMO channels, MIMO Communication for Cellular Networks emphasizes the practical performance of realistic MIMO systems. A unified set of system simulation results highlights relative performance gains of different MIMO techniques and provides insights into how best to use multiple antennas in cellular networks under various conditions. MIMO Communication for Cellular Networks describes single-user,...

  4. Laminin 5 regulates polycystic kidney cell proliferation and cyst formation.

    Science.gov (United States)

    Joly, Dominique; Berissi, Sophie; Bertrand, Amélie; Strehl, Laetitia; Patey, Natacha; Knebelmann, Bertrand

    2006-09-29

    Renal cyst formation is the hallmark of autosomal dominant polycystic kidney disease (ADPKD). ADPKD cyst-lining cells have an increased proliferation rate and are surrounded by an abnormal extracellular matrix (ECM). We have previously shown that Laminin 5 (Ln-5, a alpha(3)beta(3)gamma(2) trimer) is aberrantly expressed in the pericystic ECM of ADPKD kidneys. We report that ADPKD cells in primary cultures produce and secrete Ln-5 that is incorporated to the pericystic ECM in an in vitro model of cystogenesis. In monolayers, purified Ln-5 induces ERK activation and proliferation of ADPKD cells, whereas upon epidermal growth factor stimulation blocking endogenously produced Ln-5 with anti-gamma(2) chain antibody reduces the sustained ERK activation and inhibits proliferation. In three-dimensional gel culture, addition of purified Ln-5 stimulates cell proliferation and cyst formation, whereas blocking endogenous Ln-5 strongly inhibits cyst formation. Ligation of alpha(6)beta(4) integrin, a major Ln-5 receptor aberrantly expressed by ADPKD cells, induces beta(4) integrin phosphorylation, ERK activation, cell proliferation, and cyst formation. These findings indicate that Ln-5 is an important regulator of ADPKD cell proliferation and cystogenesis and suggest that Ln-5 gamma(2) chain and Ln-5-alpha(6)beta(4) integrin interaction both contribute to these phenotypic changes. PMID:16870608

  5. IL-13-induced proliferation of airway epithelial cells: mediation by intracellular growth factor mobilization and ADAM17

    Directory of Open Access Journals (Sweden)

    Sandifer Tracy

    2007-07-01

    Full Text Available Abstract Background The pleiotrophic cytokine interleukin (IL-13 features prominently in allergic and inflammatory diseases. In allergic asthma, IL-13 is well established as an inducer of airway inflammation and tissue remodeling. We demonstrated previously that IL-13 induces release of transforming growth factor-α (TGFα from human bronchial epithelial cells, with proliferation of these cells mediated by the autocrine/paracrine action of this growth factor. TGFα exists as an integral membrane protein and requires proteolytic processing to its mature form, with a disintegrin and metalloproteinase (ADAM17 responsible for this processing in a variety of tissues. Methods In this study, normal human bronchial epithelial (NHBE cells grown in air/liquid interface (ALI culture were used to examine the mechanisms whereby IL-13 induces release of TGFα and cellular proliferation. Inhibitors and antisense RNA were used to examine the role of ADAM17 in these processes, while IL-13-induced changes in the intracellular expression of TGFα and ADAM17 were visualized by confocal microscopy. Results IL-13 was found to induce proliferation of NHBE cells, and release of TGFα, in an ADAM17-dependent manner; however, this IL-13-induced proliferation did not appear to result solely from ADAM17 activation. Rather, IL-13 induced a change in the location of TGFα expression from intracellular to apical regions of the NHBE cells. The apical region was also found to be a site of significant ADAM17 expression, even prior to IL-13 stimulation. Conclusion Results from this study indicate that ADAM17 mediates IL-13-induced proliferation and TGFα shedding in NHBE cells. Furthermore, they provide the first example wherein a cytokine (IL-13 induces a change in the intracellular expression pattern of a growth factor, apparently inducing redistribution of intracellular stores of TGFα to the apical region of NHBE cells where expression of ADAM17 is prominent. Thus, IL-13

  6. The caudal regeneration blastema is an accumulation of rapidly proliferating stem cells in the flatworm Macrostomum lignano

    Directory of Open Access Journals (Sweden)

    Adamski Zbigniew

    2009-07-01

    Full Text Available Abstract Background Macrostomum lignano is a small free-living flatworm capable of regenerating all body parts posterior of the pharynx and anterior to the brain. We quantified the cellular composition of the caudal-most body region, the tail plate, and investigated regeneration of the tail plate in vivo and in semithin sections labeled with bromodeoxyuridine, a marker for stem cells (neoblasts in S-phase. Results The tail plate accomodates the male genital apparatus and consists of about 3,100 cells, about half of which are epidermal cells. A distinct regeneration blastema, characterized by a local accumulation of rapidly proliferating neoblasts and consisting of about 420 cells (excluding epidermal cells, was formed 24 hours after amputation. Differentiated cells in the blastema were observed two days after amputation (with about 920 blastema cells, while the male genital apparatus required four to five days for full differentiation. At all time points, mitoses were found within the blastema. At the place of organ differentiation, neoblasts did not replicate or divide. After three days, the blastema was made of about 1420 cells and gradually transformed into organ primordia, while the proliferation rate decreased. The cell number of the tail plate, including about 960 epidermal cells, was restored to 75% at this time point. Conclusion Regeneration after artificial amputation of the tail plate of adult specimens of Macrostomum lignano involves wound healing and the formation of a regeneration blastema. Neoblasts undergo extensive proliferation within the blastema. Proliferation patterns of S-phase neoblasts indicate that neoblasts are either determined to follow a specific cell fate not before, but after going through S-phase, or that they can be redetermined after S-phase. In pulse-chase experiments, dispersed distribution of label suggests that S-phase labeled progenitor cells of the male genital apparatus undergo further proliferation before

  7. miR-342-3p affects hepatocellular carcinoma cell proliferation via regulating NF-κB pathway

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Liang; Zhang, Yubao, E-mail: zhyb880077@sina.com

    2015-02-13

    Recent research indicates that non-coding microRNAs (miRNAs) help regulate basic cellular processes in many types of cancer cells. We hypothesized that overexpression of miR-342-3p might affect proliferation of hepatocellular carcinoma (HCC) cells. After confirming overexpression of miR-342-3p with qRT-PCR, MTT assay showed that HCC cell proliferation was significantly inhibited by miR-342-3p, and that it significantly decreased BrdU-positive cell proliferation by nearly sixfold. Searching for targets using three algorithms we found that miR-342-3p is related to the NF-κB pathway and luciferase assay found that IKK-γ, TAB2 and TAB3 are miR-342-3p target genes. Results of western blot on extracted nuclear proteins of HepG2 and HCT-116 cells showed that miR-342-3p reduced and miR-342-3p-in increased p65 nuclear levels and qRT-PCR found that NF-κB pathway downstream genes were downregulated by miR-342-3p and upregulated by miR-342-3p-in, confirming that miR-342 targets NF-κB pathway. Overexpression of Ikk-γ, TAB2 and TAB3 partially rescued HCC cells proliferation inhibited by miR-342-3p. Using the GSE54751 database we evaluated expression from 10 HCC samples, which strongly suggested downregulation of miR-342-3p and we also found inverse expression between miR-342-3p and its targets IKK-γ, TAB2 and TAB3 from 71 HCC samples. Our results show that miR-342-3p has a significant role in HCC cell proliferation and is suitable for investigation of therapeutic targets. - Highlights: • MiR-342-3p suppresses hepatocellular carcinoma cell proliferation. • MiR-342-3p targets IKK-γ, TAB2 and TAB3 genes. • MiR-342-3p downregulates NF-kB signaling pathway. • MiR-342-3p is downregulated in clinical hepatocellular carcinoma samples. • The expression of miR-342-3p and its target gene is inversely related.

  8. miR-342-3p affects hepatocellular carcinoma cell proliferation via regulating NF-κB pathway

    International Nuclear Information System (INIS)

    Recent research indicates that non-coding microRNAs (miRNAs) help regulate basic cellular processes in many types of cancer cells. We hypothesized that overexpression of miR-342-3p might affect proliferation of hepatocellular carcinoma (HCC) cells. After confirming overexpression of miR-342-3p with qRT-PCR, MTT assay showed that HCC cell proliferation was significantly inhibited by miR-342-3p, and that it significantly decreased BrdU-positive cell proliferation by nearly sixfold. Searching for targets using three algorithms we found that miR-342-3p is related to the NF-κB pathway and luciferase assay found that IKK-γ, TAB2 and TAB3 are miR-342-3p target genes. Results of western blot on extracted nuclear proteins of HepG2 and HCT-116 cells showed that miR-342-3p reduced and miR-342-3p-in increased p65 nuclear levels and qRT-PCR found that NF-κB pathway downstream genes were downregulated by miR-342-3p and upregulated by miR-342-3p-in, confirming that miR-342 targets NF-κB pathway. Overexpression of Ikk-γ, TAB2 and TAB3 partially rescued HCC cells proliferation inhibited by miR-342-3p. Using the GSE54751 database we evaluated expression from 10 HCC samples, which strongly suggested downregulation of miR-342-3p and we also found inverse expression between miR-342-3p and its targets IKK-γ, TAB2 and TAB3 from 71 HCC samples. Our results show that miR-342-3p has a significant role in HCC cell proliferation and is suitable for investigation of therapeutic targets. - Highlights: • MiR-342-3p suppresses hepatocellular carcinoma cell proliferation. • MiR-342-3p targets IKK-γ, TAB2 and TAB3 genes. • MiR-342-3p downregulates NF-kB signaling pathway. • MiR-342-3p is downregulated in clinical hepatocellular carcinoma samples. • The expression of miR-342-3p and its target gene is inversely related

  9. Proliferating cell nuclear antigen in neutrophil fate.

    Science.gov (United States)

    Witko-Sarsat, Véronique; Ohayon, Delphine

    2016-09-01

    The life span of a neutrophil is a tightly regulated process as extended survival is beneficial for pathogen elimination and cell death necessary to prevent cytotoxic content release from activated neutrophils at the inflammatory site. Therefore, the control between survival and death must be a dynamic process. We have previously described that proliferating cell nuclear antigen (PCNA) which is known as a nuclear protein pivotal in DNA synthesis, is a key element in controlling neutrophil survival through its association with procaspases. Contrary to the dogma which asserted that PCNA has a strictly nuclear function, in mature neutrophils, PCNA is present exclusively within the cytosol due to its nuclear export at the end of the granulocytic differentiation. More recent studies are consistent with the notion that the cytosolic scaffold of PCNA is aimed at modulating neutrophil fate rather than simply preventing death. Ultimately, targeting neutrophil survival might have important applications not just in the field of immunology and inflammation, but also in hematology and transfusion. The neutrophil emerges as a unique and powerful cellular model to unravel the basic mechanisms governing the cell cycle-independent functions of PCNA and should be considered as a leader of the pack. PMID:27558345

  10. Cellular phones: are they detrimental?

    Science.gov (United States)

    Salama, Osama E; Abou El Naga, Randa M

    2004-01-01

    The issue of possible health effects of cellular phones is very much alive in the public's mind where the rapid increase in the number of the users of cell phones in the last decade has increased the exposure of people to the electromagnetic fields (EMFs). Health consequences of long term use of mobile phones are not known in detail but available data indicates the development of non specific annoying symptoms on acute exposure to mobile phone radiations. In an attempt to determine the prevalence of such cell phones associated health manifestations and the factors affecting their occurrence, a cross sectional study was conducted in five randomly selected faculties of Alexandria University. Where, 300 individuals including teaching staff, students and literate employee were equally allocated and randomly selected among the five faculties. Data about mobile phone's users and their medical history, their pattern of mobile usage and the possible deleterious health manifestations associated with cellular phone use was collected. The results revealed 68% prevalence of mobile phone usage, nearly three quarters of them (72.5%) were complainers of the health manifestations. They suffered from headache (43%), earache (38.3%), sense of fatigue (31.6%), sleep disturbance (29.5%), concentration difficulty (28.5%) and face burning sensation (19.2%). Both univariate and multivariate analysis were consistent in their findings. Symptomatic users were found to have significantly higher frequency of calls/day, longer call duration and longer total duration of mobile phone usage/day than non symptomatic users. For headache both call duration and frequency of calls/day were the significant predicting factors for its occurrence (chi2 = 18.208, p = 0.0001). For earache, in addition to call duration, the longer period of owning the mobile phone were significant predictors (chi2 = 16.996, p = 0.0002). Sense of fatigue was significantly affected by both call duration and age of the user

  11. Suppression of WIF-1 through promoter hypermethylation causes accelerated proliferation of the aryl hydrocarbon receptor (AHR) overexpressing MCF10AT1 breast cancer cells

    International Nuclear Information System (INIS)

    Highlights: → 5-Aza-2'-deoxycytidine (AZ) causes proliferation suppression and ERα recovery. → AZ down-regulates Wnt/β-catenin pathway mainly by increasing WIF-1 expression. → Both ERα and AhR have some effects on DNA methylation in breast cancer cells. → Artificial overexpression of ERα in ER negative cells increases WIF-1 expression. → WIF-1 promoter hypermethylation is one of the major causes for accelerated proliferation. -- Abstract: The cause for increased cell proliferation in AHR overexpressing breast cancer cells still remains unknown. Here we studied the molecular basis of aggressive cell proliferation of an AHR overexpressing and ERα functionally down-regulated MCF10AT1 cell line, designated as P20E, in comparison to a matched sub-line, P20C with normal AHR expression and ERα function. We found that a 4-day treatment of P20E cells with 5-aza-2'-deoxycytidine (AZ) caused a significant suppression of cell proliferation. Such an effect of AZ was accompanied with the significant recovery of ERα function. Among diagnostic markers of AZ-induced cellular changes we found conspicuous up-regulation of mRNA expression of Wnt inhibitory factor-1 (WIF-1), particularly in P20E. The possibility of AZ-induced demethylation on the promoter of WIF-1 gene was confirmed through methylation specific PCR assay. Such AZ-induced changes in P20E cells were also accompanied with the decrease in the binding of nuclear proteins to the 32P labeled TRE (TCF response element) and the reduced accumulation of β-catenin protein in the cell nucleus, indicating the importance of Wnt/β-catenin pathway in maintaining the increased cell proliferation in P20E line over P20C line. The importance of WIF-1 in this regard has been validated by transfecting cells with siRNA against WIF-1, which caused an increase in cell proliferation. Moreover, artificial overexpression of ERα in both P20E as well as MDA-MB-231 cells increased the mRNA expression of WIF-1. Together these

  12. From cellular to tissue scales by asymptotic limits of thermostatted kinetic models

    Science.gov (United States)

    Bianca, Carlo; Dogbe, Christian; Lemarchand, Annie

    2016-02-01

    Tumor growth strictly depends on the interactions occurring at the cellular scale. In order to obtain the linking between the dynamics described at tissue and cellular scales, asymptotic methods have been employed, consisting in deriving tissue equations by suitable limits of mesoscopic models. In this paper, the evolution at the cellular scale is described by thermostatted kinetic theory that include conservative, nonconservative (proliferation, destruction and mutations), stochastic terms, and the role of external agents. The dynamics at the tissue scale (cell-density evolution) is obtained by performing a low-field scaling and considering the related convergence of the rescaled framework when the scaling parameter goes to zero.

  13. Novel chlorinated dibenzofurans isolated from the cellular slime mold, Polysphondylium filamentosum, and their biological activities.

    Science.gov (United States)

    Kikuchi, Haruhisa; Kubohara, Yuzuru; Nguyen, Van Hai; Katou, Yasuhiro; Oshima, Yoshiteru

    2013-08-01

    Cellular slime molds are expected to have the huge potential for producing secondary metabolites including polyketides, and we have studied the diversity of secondary metabolites of cellular slime molds for their potential utilization as new biological resources for natural product chemistry. From the methanol extract of fruiting bodies of Polysphondylium filamentosum, we obtained new chlorinated benzofurans Pf-1 (4) and Pf-2 (5) which display multiple biological activities; these include stalk cell differentiation-inducing activity in the well-studied cellular slime mold, Dictyostelium discoideum, and inhibitory activities on cell proliferation in mammalian cells and gene expression in Drosophila melanogaster. PMID:23746784

  14. Nitric oxide-releasing prodrug triggers cancer cell death through deregulation of cellular redox balance

    Directory of Open Access Journals (Sweden)

    Anna E. Maciag

    2013-01-01

    Full Text Available JS-K is a nitric oxide (NO-releasing prodrug of the O2-arylated diazeniumdiolate family that has demonstrated pronounced cytotoxicity and antitumor properties in a variety of cancer models both in vitro and in vivo. The current study of the metabolic actions of JS-K was undertaken to investigate mechanisms of its cytotoxicity. Consistent with model chemical reactions, the activating step in the metabolism of JS-K in the cell is the dearylation of the diazeniumdiolate by glutathione (GSH via a nucleophilic aromatic substitution reaction. The resulting product (CEP/NO anion spontaneously hydrolyzes, releasing two equivalents of NO. The GSH/GSSG redox couple is considered to be the major redox buffer of the cell, helping maintain a reducing environment under basal conditions. We have quantified the effects of JS-K on cellular GSH content, and show that JS-K markedly depletes GSH, due to JS-K's rapid uptake and cascading release of NO and reactive nitrogen species. The depletion of GSH results in alterations in the redox potential of the cellular environment, initiating MAPK stress signaling pathways, and inducing apoptosis. Microarray analysis confirmed signaling gene changes at the transcriptional level and revealed alteration in the expression of several genes crucial for maintenance of cellular redox homeostasis, as well as cell proliferation and survival, including MYC. Pre-treating cells with the known GSH precursor and nucleophilic reducing agent N-acetylcysteine prevented the signaling events that lead to apoptosis. These data indicate that multiplicative depletion of the reduced glutathione pool and deregulation of intracellular redox balance are important initial steps in the mechanism of JS-K's cytotoxic action.

  15. Real time kinetic flow cytometry measurements of cellular parameter changes evoked by nanosecond pulsed electric field.

    Science.gov (United States)

    Orbán, Csaba; Pérez-García, Esther; Bajnok, Anna; McBean, Gethin; Toldi, Gergely; Blanco-Fernandez, Alfonso

    2016-05-01

    Nanosecond pulsed electric field (nsPEF) is a novel method to increase cell proliferation rate. The phenomenon is based on the microporation of cellular organelles and membranes. However, we have limited information on the effects of nsPEF on cell physiology. Several studies have attempted to describe the effects of this process, however no real time measurements have been conducted to date. In this study we designed a model system which allows the measurement of cellular processes before, during and after nsPEF treatment in real time. The system employs a Vabrema Mitoplicator(TM) nsPEF field generating instrument connected to a BD Accuri C6 cytometer with a silicon tube led through a peristaltic pump. This model system was applied to observe the effects of nsPEF in mammalian C6 glioblastoma (C6 glioma) and HEK-293 cell lines. Viability (using DRAQ7 dye), intracellular calcium levels (using Fluo-4 dye) and scatter characteristics were measured in a kinetic manner. Data were analyzed using the FACSKin software. The viability and morphology of the investigated cells was not altered upon nsPEF treatment. The response of HEK-293 cells to ionomycin as positive control was significantly lower in the nsPEF treated samples compared to non-treated cells. This difference was not observed in C6 cells. FSC and SSC values were not altered significantly by the nsPEF treatment. Our results indicate that this model system is capable of reliably investigating the effects of nsPEF on cellular processes in real time. © 2016 International Society for Advancement of Cytometry. PMID:26990601

  16. Cellular dosimetry in nuclear medicine imaging: training

    International Nuclear Information System (INIS)

    The radionuclides used in nuclear medicine imaging emit not only diagnostically useful photons, but also energy electron emissions, responsible for dose heterogeneity at the cellular level. The mean dose delivered to the cell nucleus by electron emissions of 99mTc, 123I, 111In, 67Ga, and 201Tl, has been calculated, for the cell nucleus, a cytoplasmic and a cell membrane distribution of radioactivity. This model takes into account both the self-dose which results from the radionuclide located in the target cell, and the cross-dose, which comes from the surrounding cells. The results obtained by cellular dosimetry (Dcel) have been compared with those obtained with conventional dosimetry (Dconv), by assuming the same amount of radioactivity per cell. Cellular dosimetry shows, for a cytoplasmic and a cell membrane distributions of radioactivity, that the main contribution to the dose to the cell nucleus, comes from the surrounding cells. On the other hand, for a cell nucleus distribution of radioactivity, the self-dose is not negligible and may be the main contribution. The comparison between cellular and conventional dosimetry shows that Dcel/Dconv ratio ranges from 0.61 and O.89, in case of a cytoplasmic and a cell membrane distributions of radioactivity, depending on the radionuclide and cell dimensions. Thus, conventional dosimetry slightly overestimates the mean dose to the cell nucleus. On the other hand, Dcel/Dconv ranges from 1.1 to 75, in case of a cell nucleus distribution of radioactivity. Conventional dosimetry may strongly underestimates the absorbed dose to the nucleus, when radioactivity is located in the nucleus. The study indicates that in nuclear medicine imaging, cellular dosimetry may lead to a better understanding of biological effects of radiopharmaceuticals. (authors)

  17. Cellular glutathione prevents cytolethality of monomethylarsonic acid

    International Nuclear Information System (INIS)

    Inorganic arsenicals are clearly toxicants and carcinogens in humans. In mammals, including humans, inorganic arsenic often undergoes methylation, forming compounds such as monomethylarsonic acid (MMAsV) and dimethylarsinic acid (DMAsV). However, much less information is available on the in vitro toxic potential or mechanisms of these methylated arsenicals, especially MMAsV. We studied the molecular mechanisms of in vitro cytolethality of MMAsV using a rat liver epithelial cell line (TRL 1215). MMAsV was not cytotoxic in TRL 1215 cells even at concentrations exceeding 10 mM, but it became weakly cytotoxic and induced both necrotic and apoptotic cell death when cellular reduced glutathione (GSH) was depleted with the glutathione synthase inhibitor, L-buthionine-[S,R]-sulfoximine (BSO), or the glutathione reductase inhibitor, carmustine. Similar results were observed in the other mammalian cells, such as human skin TIG-112 cells, chimpanzee skin CRT-1609 cells, and mouse metallothionein (MT) positive and MT negative embryonic cells. Ethacrynic acid (EA), an inhibitor of glutathione S-transferase (GST) that catalyses GSH-substrate conjugation, also enhanced the cytolethality of MMAsV, but aminooxyacetic acid (AOAA), an inhibitor of β-lyase that catalyses the final breakdown of GSH-substrate conjugates, had no effect. Both the cellular GSH levels and the cellular GST activity were increased by the exposure to MMAsV in TRL 1215 cells. On the other hand, the addition of exogenous extracellular GSH enhanced the cytolethality of MMAsV, although cellular GSH levels actually prevented the cytolethality of combined MMAsV and exogenous GSH. These findings indicate that human arsenic metabolite MMAsV is not a highly toxic compound in mammalian cells, and the level of cellular GSH is critical to its eventual toxic effects

  18. Overexpression of UbcH10 alternates the cell cycle profile and accelerate the tumor proliferation in colon cancer

    Directory of Open Access Journals (Sweden)

    Hatoh Shinji

    2009-03-01

    Full Text Available Abstract Background UbcH10 participates in proper metaphase to anaphase transition, and abrogation of UbcH10 results in the premature separation of sister chromatids. To assess the potential role of UbcH10 in colon cancer progression, we analyzed the clinicopathological relevance of UbcH10 in colon cancer. Methods We firstly screened the expression profile of UbcH10 in various types of cancer tissues as well as cell lines. Thereafter, using the colon cancer cells line, we manipulated the expression of UbcH10 and evaluated the cell cycle profile and cellular proliferations. Furthermore, the clinicopathological significance of UbcH10 was immunohistologically evaluated in patients with colon cancer. Statistical analysis was performed using the student's t-test and Chi-square test. Results Using the colon cancer cells, depletion of UbcH10 resulted in suppression of cellular growth whereas overexpression of UbcH10 promoted the cellular growth and oncogenic cellular growth. Mitotic population was markedly alternated by the manipulation of UbcH10 expression. Immunohistochemical analysis indicated that UbcH10 was significantly higher in colon cancer tissue compared with normal colon epithelia. Furthermore, the clinicopathological evaluation revealed that UbcH10 was associated with high-grade histological tumors. Conclusion The results show the clinicopathological significance of UbcH10 in the progression of colon cancer. Thus UbcH10 may act as a novel biomarker in patients with colon cancer.

  19. Effects of negative pressure wound therapy on mesenchymal stem cells proliferation and osteogenic differentiation in a fibrin matrix.

    Directory of Open Access Journals (Sweden)

    Jin Zhu

    Full Text Available Vacuum-assisted closure (VAC negative pressure wound therapy (NPWT has been proven to be an effective therapeutic method for the treatment of recalcitrant wounds. However, its role in bone healing remains to be unclear. Here, we investigated the effects of NPWT on rat periosteum-derived mesenchymal stem cells (P-MSCs proliferation and osteoblastic differentiation in a 3D fibrin matrix. P-MSCs underwent primary culture for three passages before being used to construct cell clots. The fibrin clots were incubated with NPWT under continuous suction at -125 mmHg in a subatmospheric perfusion bioreactor. Clots exposed to atmospheric pressure served as the static control. Compared to the control group, cell proliferation significantly increased in NPWT group after incubation for 3 days. There was no statistical difference in apoptosis rate between two groups. The ALP activity and mineralization of P-MSCs all increased under continuous suction. The expressions of collagen type 1 and transcription factor Cbfa-1 were higher at the 1-, 3-, and 7-day timepoints and the expressions of osteocalcin and integrin β5 were higher at the 3-, and 7-day timepoints in the NPWT group. These results indicate that a short time treatment with NPWT, applied with continuous suction at -125 mmHg, can enhance cellular proliferation of P-MSCs and induce the differentiation toward an osteogenic phenotype. The mechanotransduction molecule integrin β5 was found to be highly expressed after NPWT treatment, which indicates that NPWT may play a positive role in fracture healing through enhance bone formation and decrease bone resorption.

  20. Videography supported adhesion, and proliferation behavior of MG-63 osteoblastic cells on 2.5D titania nanotube matrices.

    Science.gov (United States)

    Manurung, Robeth Viktoria; Fu, Pei-Wen; Chu, Yeh-Shiu; Lo, Chun-Min; Chattopadhyay, Surojit

    2016-04-01

    Human osteosarcoma cells MG-63 were cultured on anodically etched titania nanotubes (TiO2 NT), with diameters ranging from 40-100 nm, to study the correlations between cell proliferation and adhesion on the 2.5 dimensional (2.5D) extracellular matrix (ECM). Unlike other reports, mostly based on mouse stem cells, and 2D cell culture, our studies indicate that the 2.5D NT promote higher proliferation and activity, but less 2D adhesion. Proliferation of the MG-63 cells was significantly higher in the NTs, the best being the 70 nm diameter sample, compared to planar titania (control). This is consistent with previous studies. However, cellular adhesion was stronger on TiO2 NT with increasing diameter, and highest on the control as obtained from shear stress measurement, paxilin imaging, and western blot measurements probing focal adhesion kinase, p130 CAS, and extracellular-regulated kinase, in addition to cell morphology imaging by fluorescence microscopy. We provide direct videography of cell migration, and cell speed data indicating faster filopodial activity on the TiO2 NT surfaces having lower adhesion. This evidence was not available previously. The NT matrices promote cells with smaller surface area, because of less 2D stretching. In contrast, on comparatively planar 2D-like surfaces uniaxial stretching of the cell body with strong anchoring of the filopodia, resulted in larger cell surface area, and demonstrated stronger adhesion. The difference in the results, with those previously published, may be generally attributed to, among others, the use of mouse stem cells (human osteosarcoma used here), and unannealed as-grown TiO2 NTs used previously (annealed ECMs used here). © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 842-852, 2016. PMID:26650774

  1. Essential components for ex vivo proliferation of mesenchymal stromal cells.

    Science.gov (United States)

    Fekete, Natalie; Rojewski, Markus Thomas; Lotfi, Ramin; Schrezenmeier, Hubert

    2014-02-01

    Mesenchymal stromal cells (MSCs) are highly interesting candidates for clinical applications in regenerative medicine. Due to their low occurrence in human tissues, extensive in vitro expansion is necessary to obtain sufficient cell numbers applicable as a clinical dose in the context of cellular therapy. Current cell culture media formulations for the isolation and expansion of MSCs include fetal calf serum (FCS), human AB serum (ABS), or human platelet lysate (PL) as a supplement. However, these established supplements are inherently ill-defined formulations that contain a variety of bioactive molecules in varying batch-to-batch compositions and the risk of transmitting pathogens that escape routine screening procedures. In this study, we have comparatively characterized the capacity of commonly used basal media, such as the Minimum Essential Medium alpha (αMEM), Dulbecco's modified Eagle's medium (DMEM), Iscove's Modified Dulbecco's Medium (IMDM), and RPMI 1640 as well as human- and animal-derived supplements, that is, PL, ABS, and FCS to stimulate cell proliferation. MSC proliferation was observed to be optimal in the PL-supplemented αMEM. Using a combinatorial approach, we then assessed a library of soluble factors, including mitogens (TGF-β1, Activin A, bFGF, EGF, IGF-I, PDGF-BB, and VEGF), chemokines (CCL21, CCL25, CXCL12, and RANTES), proteins (human serum albumin), lipids (e.g., oleic acid, linoleic acid, and arachidonic acid), and hormones (dexamethasone, insulin, and TSH), to create a defined medium as well as coating of cell culture surfaces to promote robust MSC proliferation in vitro. A combination of recombinant human factors partially met the nutritional requirements of bone marrow-derived MSCs, and was able to promote cell proliferation comparable to about 5% PL if supplemented with auxiliary 0.6%-1.2% PL. Maximal MSC proliferation was achieved by combining 5% PL with a cocktail of recombinant factors and did not depend on coating of cell

  2. Proliferation prevention in the commercial fuel cycle

    International Nuclear Information System (INIS)

    This website contains the papers presented on November 17, 1998 during the session, ''Proliferation Prevention in the Commercial Fuel Cycle,'' at the American Nuclear Society meeting in Washington, DC. The abstracts are in a separate section; individual papers also contain the author's bio and e-mail address. In the session planning phase, it was suggested that the following questions and other relevant issues be addressed: * What are the difficulties and issues with defining and enforcing international standards for the physical protection of Pu and HEU (beyond the Convention on the Physical protection of Nuclear Material, which primarily addresses transportation)? * How do we (or can we) keep nuclear technology in general, and reprocessing and enrichment technologies in particular, from spreading to undesirable organizations (including governments), in light of Article IV of the NPT? Specifically, can we (should we) prevent the construction of light-water reactors in Iran; and should we support the construction of light-water reactors in North Korea? * Are there more proliferation-resistant fuel cycles that would be appropriate in developing countries? * Can the concept of ''nonproliferation credentials'' be defined in a useful way? * Is there historical evidence to indicate that reprocessing (or enrichment of HEU) in the US, Japan, or the EURATOM countries has impacted the acquisition (or attempted acquisition) of nuclear weapons by other nations or groups? * What is the impact of a fissile material cutoff treaty (FMCT) be on commercial nuclear fuel cycles? * Does MOX spent fuel present a greater proliferation risk than LEU spent fuel? Although the authors did not explicitly attempt to answer all these questions, they did enlighten us about a number of these and related issues

  3. Actual problems of cellular cardiomyoplasty

    Directory of Open Access Journals (Sweden)

    Bulat Kaupov

    2010-04-01

    Full Text Available The paper provides review of cellular technologies used incardiology, describes types of cellular preparations depending onsources of cells and types of compounding cells. The generalmechanisms of therapies with stem cells applications are described.Use of cellular preparations for treatment of cardiovascular diseasesand is improvement of the forecast at patients with heartinsufficiency of various genesis is considered as alternative topractice with organ transplantations. Efforts of biotechnologicallaboratories are directed on search of optimum population of cellsfor application in cardiology and studying of mechanisms andfactors regulating function of cardiac stem cells.

  4. Ro60 overexpression contributes to proliferation and sensitivity of tumor cells to γ-irradiation

    International Nuclear Information System (INIS)

    Objective: To investigate the expression and subcellular localization of RNA-binding protein Ro60 in neoplasms before and after γ-ray irradiation, and the function of Ro60 in tumor cell proliferation and radio-sensitivity. Methods: The eukaryotic expression plasmid of mGFP-Ro60 was constructed and transfected into HCT116 and MCF7 tumor cells. The cellular localization of Ro60 was examined before and after irradiation. Cell proliferation and radio-sensitivity were detected by CCK8 and trypan blue assay. Results: The result of immunoblotting showed that tumor cells expressed Ro60 protein. The irradiation increased Ro60 expression and induced significant nuclear aggregation of Ro60. The cell proliferation before and after irradiation was drastically reduced while cell death increased in Ro60 over expressed tumor cells. Conclusion: γ-ray irradiation alters Ro60 expression and localization, and Ro60 plays an important role in tumor cell proliferation and radio-sensitivity. (authors)

  5. Proliferation Vulnerability Red Team report

    Energy Technology Data Exchange (ETDEWEB)

    Hinton, J.P.; Barnard, R.W.; Bennett, D.E. [and others

    1996-10-01

    This report is the product of a four-month independent technical assessment of potential proliferation vulnerabilities associated with the plutonium disposition alternatives currently under review by DOE/MD. The scope of this MD-chartered/Sandia-led study was limited to technical considerations that could reduce proliferation resistance during various stages of the disposition processes below the Stored Weapon/Spent Fuel standards. Both overt and covert threats from host nation and unauthorized parties were considered. The results of this study will be integrated with complementary work by others into an overall Nonproliferation and Arms Control Assessment in support of a Secretarial Record of Decision later this year for disposition of surplus U.S. weapons plutonium.

  6. Leading research on artificial techniques controlling cellular function; Saibo zoshoku seigyo gijutsu no sendo kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-03-01

    Advanced research and its applicability were surveyed to apply the advanced functional cells to industry. The basic target was set to develop, produce, control and utilize the functional cells, such as intelligent materials and self-regulation bioreactors. The regulation factors regarding apotosis, which is a process of cell suicide programmed within the cell itself of multicellular organisms, cell cycle and aging/ageless were investigated. Furthermore, the function of regulatory factors was investigated at the protein level. Injection of factors regulating cellular function and tissue engineering required for the regulation of cell proliferation were investigated. Tissue engineering is considered to be the intracellular regulation by gene transduction and the extracellular regulation by culture methods, such as coculture. Analysis methods for cell proliferation and function of living cells were investigated using the probes recognizing molecular structure. Novel biomaterials, artificial organ systems, cellular therapy and useful materials were investigated for utilizing the regulation techniques of cell proliferation. 425 refs., 85 figs., 9 tabs.

  7. Optimizing Cellular Networks Enabled with Renewal Energy via Strategic Learning

    Science.gov (United States)

    Sohn, Insoo; Liu, Huaping; Ansari, Nirwan

    2015-01-01

    An important issue in the cellular industry is the rising energy cost and carbon footprint due to the rapid expansion of the cellular infrastructure. Greening cellular networks has thus attracted attention. Among the promising green cellular network techniques, the renewable energy-powered cellular network has drawn increasing attention as a critical element towards reducing carbon emissions due to massive energy consumption in the base stations deployed in cellular networks. Game theory is a branch of mathematics that is used to evaluate and optimize systems with multiple players with conflicting objectives and has been successfully used to solve various problems in cellular networks. In this paper, we model the green energy utilization and power consumption optimization problem of a green cellular network as a pilot power selection strategic game and propose a novel distributed algorithm based on a strategic learning method. The simulation results indicate that the proposed algorithm achieves correlated equilibrium of the pilot power selection game, resulting in optimum green energy utilization and power consumption reduction. PMID:26167934

  8. Optimizing Cellular Networks Enabled with Renewal Energy via Strategic Learning.

    Directory of Open Access Journals (Sweden)

    Insoo Sohn

    Full Text Available An important issue in the cellular industry is the rising energy cost and carbon footprint due to the rapid expansion of the cellular infrastructure. Greening cellular networks has thus attracted attention. Among the promising green cellular network techniques, the renewable energy-powered cellular network has drawn increasing attention as a critical element towards reducing carbon emissions due to massive energy consumption in the base stations deployed in cellular networks. Game theory is a branch of mathematics that is used to evaluate and optimize systems with multiple players with conflicting objectives and has been successfully used to solve various problems in cellular networks. In this paper, we model the green energy utilization and power consumption optimization problem of a green cellular network as a pilot power selection strategic game and propose a novel distributed algorithm based on a strategic learning method. The simulation results indicate that the proposed algorithm achieves correlated equilibrium of the pilot power selection game, resulting in optimum green energy utilization and power consumption reduction.

  9. Optimizing Cellular Networks Enabled with Renewal Energy via Strategic Learning.

    Science.gov (United States)

    Sohn, Insoo; Liu, Huaping; Ansari, Nirwan

    2015-01-01

    An important issue in the cellular industry is the rising energy cost and carbon footprint due to the rapid expansion of the cellular infrastructure. Greening cellular networks has thus attracted attention. Among the promising green cellular network techniques, the renewable energy-powered cellular network has drawn increasing attention as a critical element towards reducing carbon emissions due to massive energy consumption in the base stations deployed in cellular networks. Game theory is a branch of mathematics that is used to evaluate and optimize systems with multiple players with conflicting objectives and has been successfully used to solve various problems in cellular networks. In this paper, we model the green energy utilization and power consumption optimization problem of a green cellular network as a pilot power selection strategic game and propose a novel distributed algorithm based on a strategic learning method. The simulation results indicate that the proposed algorithm achieves correlated equilibrium of the pilot power selection game, resulting in optimum green energy utilization and power consumption reduction. PMID:26167934

  10. Phenobarbital-induced hepatocellular proliferation: anti-bromodeoxyuridine and anti-proliferating cell nuclear antigen immunocytochemistry.

    Science.gov (United States)

    Jones, H B; Clarke, N A; Barrass, N C

    1993-01-01

    We report modifications to immunocytochemical detection procedures for proliferating cell nuclear antigen (PCNA) which permit its identification in liver samples previously fixed for BrdU immunocytochemistry. Both methods have been used for the assessment of phenobarbital-induced cell proliferation in rat liver. The difficulties associated with the hitherto unsuccessful application of PCNA immunocytochemical methods to tissues fixed in formalin for BrdU visualization were overcome by epitope unmasking with acid hydrolysis, extension of primary antiserum (PC10) incubation, and employment of streptavidin-ABC-HRP. BrdU delivery via osmotic minipumps for 48 hr before euthanasia, followed by fixation in cold formalin for 14 days, yielded reliable and reproducible hepatocellular labeling and a peak of cell proliferation in all lobes on Day 3 (i.e., labeling during Days 1-3) of dosing with 80 mg/kg/day phenobarbital. Labeling indices (LI) of both control and phenobarbital-treated liver were lower in the left and right median lobes as compared with the lateral lobes. In sections of the left lateral lobe from the same liver, PCNA immunocytochemistry revealed a peak of proliferative activity (about one third of the maximum LI generated by BrdU incorporation) on Day 1. These findings, together with the advantages and disadvantages of both techniques, are discussed in the context of their applications to different investigative requirements. PMID:8093255

  11. Epstein-Barr virus growth/latency III program alters cellular microRNA expression

    International Nuclear Information System (INIS)

    The Epstein-Barr virus (EBV) is associated with lymphoid and epithelial cancers. Initial EBV infection alters lymphocyte gene expression, inducing cellular proliferation and differentiation as the virus transitions through consecutive latency transcription programs. Cellular microRNAs (miRNAs) are important regulators of signaling pathways and are implicated in carcinogenesis. The extent to which EBV exploits cellular miRNAs is unknown. Using micro-array analysis and quantitative PCR, we demonstrate differential expression of cellular miRNAs in type III versus type I EBV latency including elevated expression of miR-21, miR-23a, miR-24, miR-27a, miR-34a, miR-146a and b, and miR-155. In contrast, miR-28 expression was found to be lower in type III latency. The EBV-mediated regulation of cellular miRNAs may contribute to EBV signaling and associated cancers

  12. Origami interleaved tube cellular materials

    International Nuclear Information System (INIS)

    A novel origami cellular material based on a deployable cellular origami structure is described. The structure is bi-directionally flat-foldable in two orthogonal (x and y) directions and is relatively stiff in the third orthogonal (z) direction. While such mechanical orthotropicity is well known in cellular materials with extruded two dimensional geometry, the interleaved tube geometry presented here consists of two orthogonal axes of interleaved tubes with high interfacial surface area and relative volume that changes with fold-state. In addition, the foldability still allows for fabrication by a flat lamination process, similar to methods used for conventional expanded two dimensional cellular materials. This article presents the geometric characteristics of the structure together with corresponding kinematic and mechanical modeling, explaining the orthotropic elastic behavior of the structure with classical dimensional scaling analysis. (paper)

  13. Collagen coated tantalum substrate for cell proliferation.

    Science.gov (United States)

    Li, Yinli; Zhang, Shuai; Guo, Lijun; Dong, Mingdong; Liu, Bo; Mamdouh, Wael

    2012-06-15

    The extracellular matrix (ECM) plays a key role in cell culture in various physiological and pathological processes in the field of tissue engineering. Recently, the type I collagen ECM has been widely utilized in vitro model systems for the attachment of many different cell lines since it has multi-functions in human tissues. For example it accounts for 6% of the weight of strong, tendinous muscles. In this paper, we reported a new material by coating tantalum (Ta), one highly biocompatible metal, with type I collagen fibrils. The morphology of the new material was studied by high resolution atomic force microscope. It was shown that the adhesion force between type I collagen fibrils network and Ta was strong enough to overcome surface defects. A possible way to explain the phenomenon is that the longitudinal periodicity of collagen fibrils matches the grain size of the Ta domains, which results in increase of the physical adsorption contact area, thereby inducing the dramatic adhesion enhancement between collagen fibrils and Ta. The obtained material was then employed as a template for cell proliferation. Although the surface of this template is more hydrophobic by comparison with the bare Ta surface, the cells on this material were successfully incubated, indicating that the collagen coated Ta might be used as the buffer layer for proliferating cells in hydrophobic biomaterials. PMID:22494669

  14. Cellular cardiomyoplasty A preliminary clinical report

    International Nuclear Information System (INIS)

    Background: Cellular cardiomyoplasty is the method of transplanting myogenic cells into injured myocardium to restore the lost heart muscle cells and to improve ventricular function. Method: Three patients, all with a history of coronary heart disease, underwent coronary artery bypass grafting and implantation of autologous satellite cells. A muscle biopsy of 2-4 g from the right vastus lateralis muscle was obtained for satellite cell (myogenic stem cell from skeletal muscle) isolation and proliferation before implanted into the donor's heart. The cells were suspended in serum-free medium and injected into 30-40 sites at and around the ischemic areas just before reversing the hypothermic cardioplegia to eliminate arrhythmia and to improve retention. After recovery, each patient was maintained at the intensive care unit for 3-4 days with ECG monitoring before transferring to the patient floor. Results: All patients survived the procedure with an uneventful recovery and were discharged from the hospital. At 3-4 months follow-up examination, increased left ventricular ejection fraction of 11% (35-46%), 5.4% (40-45.4%) and 1% (40-41%) and decreased left ventricular diastolic diameter of 4, 2 and 9 mm were observed for the patients, respectively. Arrhythmia was not detected during the follow-up evaluation by ECG. Improved perfusion (99mTC-MIBI) and increased metabolic activity (18F-deoxyglucose) were found at the sites of satellite cell implantation. Significant increase of wall thickness and movement at the areas of cell injection was also observed using 2D-echo. Conclusion: Cellular cardiomyoplasty using autologous satellite cells is a safe procedure with encouraging beneficial outcomes in patients

  15. The EJC component Magoh regulates proliferation and expansion of neural crest-derived melanocytes.

    Science.gov (United States)

    Silver, Debra L; Leeds, Karen E; Hwang, Hun-Way; Miller, Emily E; Pavan, William J

    2013-03-15

    Melanoblasts are a population of neural crest-derived cells that generate the pigment-producing cells of our body. Defective melanoblast development and function underlies many disorders including Waardenburg syndrome and melanoma. Understanding the genetic regulation of melanoblast development will help elucidate the etiology of these and other neurocristopathies. Here we demonstrate that Magoh, a component of the exon junction complex, is required for normal melanoblast development. Magoh haploinsufficient mice are hypopigmented and exhibit robust genetic interactions with the transcription factor, Sox10. These phenotypes are caused by a marked reduction in melanoblast number beginning at mid-embryogenesis. Strikingly, while Magoh haploinsufficiency severely reduces epidermal melanoblasts, it does not significantly affect the number of dermal melanoblasts. These data indicate Magoh impacts melanoblast development by disproportionately affecting expansion of epidermal melanoblast populations. We probed the cellular basis for melanoblast reduction and discovered that Magoh mutant melanoblasts do not undergo increased apoptosis, but instead are arrested in mitosis. Mitotic arrest is evident in both Magoh haploinsufficient embryos and in Magoh siRNA treated melanoma cell lines. Together our findings indicate that Magoh-regulated proliferation of melanoblasts in the dermis may be critical for production of epidermally-bound melanoblasts. Our results point to a central role for Magoh in melanocyte development. PMID:23333945

  16. Cellular mechanisms during vascular development

    OpenAIRE

    Blum, Yannick

    2012-01-01

    The vascular system is an essential organ in vertebrate animals and provides the organism with enough oxygen and nutrients. It is composed of an interconnected network of blood vessels, which form using a number of different morphogenetic mechanisms. Angiogenesis describes the formation of new blood vessels from preexisting vessels. A number of molecular pathways have been shown to be essential during angiogenesis. However, cellular architecture of blood vessels as well as cellular mechanisms...

  17. Predictive Modelling of Cellular Load

    OpenAIRE

    Carolan, Emmett; McLoone, Seamus; Farrell, Ronan

    2015-01-01

    This work examines the temporal dynamics of cellular load in four Irish regions. Large scale underutilisation of network resources is identified both at the regional level and at the level of individual cells. Cellular load is modeled and prediction intervals are generated. These prediction intervals are used to put an upper bound on usage in a particular cell at a particular time. Opportunities for improvements in network utilization by incorporating these upper bounds on usage are identifie...

  18. Cellular automaton for chimera states

    OpenAIRE

    García-Morales, Vladimir

    2016-01-01

    A minimalistic model for chimera states is presented. The model is a cellular automaton (CA) which depends on only one adjustable parameter, the range of the nonlocal coupling, and is built from elementary cellular automata and the majority (voting) rule. This suggests the universality of chimera-like behavior from a new point of view: Already simple CA rules based on the majority rule exhibit this behavior. After a short transient, we find chimera states for arbitrary initial conditions, the...

  19. Suppression of Ov-grn-1 encoding granulin of Opisthorchis viverrini inhibits proliferation of biliary epithelial cells

    OpenAIRE

    Papatpremsiri, Atiroch; Smout, Michael J.; Loukas, Alex; Brindley, Paul J.; Sripa, Banchob; Laha, Thewarach

    2014-01-01

    Multistep processes likely underlie cholangiocarcinogenesis induced by chronic infection with the fish-borne liver fluke, Opisthorchis viverrini. One process appears to be cellular proliferation of the host bile duct epithelia driven by excretory-secretory (ES) products of this pathogen. Specifically, the secreted growth factor Ov-GRN-1, a liver fluke granulin, is a prominent component of ES and a known driver of hyper-proliferation of cultured human and mouse cells in vitro. We show potent h...

  20. Heme oxygenase-1 regulates cell proliferation via carbon monoxide-mediated inhibition of T-type Ca2+ channels

    OpenAIRE

    Duckles, Hayley; Boycott, Hannah E.; Al-Owais, Moza M.; Elies, Jacobo; Johnson, Emily; Dallas, Mark L.; Porter, Karen E.; Giuntini, Francesca; Boyle, John P.; Scragg, Jason L.; Peers, Chris

    2014-01-01

    Induction of the antioxidant enzyme heme oxygenase-1 (HO-1) affords cellular protection and suppresses proliferation of vascular smooth muscle cells (VSMCs) associated with a variety of pathological cardiovascular conditions including myocardial infarction and vascular injury. However, the underlying mechanisms are not fully understood. Over-expression of Cav3.2 T-type Ca2+ channels in HEK293 cells raised basal [Ca2+]i and increased proliferation as compared with non-transfected cells. Prolif...

  1. Low-power GaAlAs laser irradiation promotes the proliferation and osteogenic differentiation of stem cells via IGF1 and BMP2.

    Directory of Open Access Journals (Sweden)

    Jyun-Yi Wu

    Full Text Available Low-power laser irradiation (LPLI has been found to induce various biological effects and cellular processes. Also, LPLI has been shown to promote fracture repair. Until now, it has been unclear how LPLI promotes bone formation and fracture healing. The aim of this study was to investigate the potential mechanism of LPLI-mediated enhancement of bone formation using mouse bone marrow mesenchymal stem cells (D1 cells. D1 cells were irradiated daily with a gallium-aluminum-arsenide (GaAlAs laser at dose of 0, 1, 2, or 4 J/cm(2. The lactate dehydrogenase (LDH assay showed no cytotoxic effects of LPLI on D1 cells, and instead, LPLI at 4 J/cm(2 significantly promoted D1 cell proliferation. LPLI also enhanced osteogenic differentiation in a dose-dependent manner and moderately increased expression of osteogenic markers. The neutralization experiments indicated that LPLI regulated insulin-like growth factor 1 (IGF1 and bone morphogenetic protein 2 (BMP2 signaling to promote cell proliferation and/or osteogenic differentiation. In conclusion, our study suggests that LPLI may induce IGF1 expression to promote both the proliferation and osteogenic differentiation of D1 cells, whereas it may induce BMP2 expression primarily to enhance osteogenic differentiation.

  2. In vitro proliferation of adult human beta-cells.

    Directory of Open Access Journals (Sweden)

    Sabine Rutti

    Full Text Available A decrease in functional beta-cell mass is a key feature of type 2 diabetes. Glucagon-like peptide 1 (GLP-1 analogues induce proliferation of rodent beta-cells. However, the proliferative capacity of human beta-cells and its modulation by GLP-1 analogues remain to be fully investigated. We therefore sought to quantify adult human beta-cell proliferation in vitro and whether this is affected by the GLP-1 analogue liraglutide.Human islets from 7 adult cadaveric organ donors were dispersed into single cells. Beta-cells were purified by FACS. Non-sorted cells and the beta-cell enriched ("beta-cells" population were plated on extracellular matrix from rat (804G and human bladder carcinoma cells (HTB9 or bovine corneal endothelial ECM (BCEC. Cells were maintained in culture+/-liraglutide for 4 days in the presence of BrdU.Rare human beta-cell proliferation could be observed either in the purified beta-cell population (0.051±0.020%; 22 beta-cells proliferating out of 84'283 beta-cells counted or in the non-sorted cell population (0.055±0.011%; 104 proliferating beta-cells out of 232'826 beta-cells counted, independently of the matrix or the culture conditions. Liraglutide increased human beta-cell proliferation on BCEC in the non-sorted cell population (0.082±0.034% proliferating beta-cells vs. 0.017±0.008% in control, p<0.05.These results indicate that adult human beta-cell proliferation can occur in vitro but remains an extremely rare event with these donors and particular culture conditions. Liraglutide increases beta-cell proliferation only in the non-sorted cell population and only on BCEC. However, it cannot be excluded that human beta-cells may proliferate to a greater extent in situ in response to natural stimuli.

  3. Homeobox A7 stimulates breast cancer cell proliferation by up-regulating estrogen receptor-alpha

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yu [Department of Reproductive Endocrinology, Women’s Hospital, School of Medicine, Zhejiang University, Hangzhou 310006 (China); Department of Obstetrics and Gynaecology, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia V5Z 4H4 (Canada); Cheng, Jung-Chien [Department of Obstetrics and Gynaecology, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia V5Z 4H4 (Canada); Huang, He-Feng, E-mail: huanghefg@hotmail.com [Department of Reproductive Endocrinology, Women’s Hospital, School of Medicine, Zhejiang University, Hangzhou 310006 (China); Leung, Peter C.K., E-mail: peter.leung@ubc.ca [Department of Reproductive Endocrinology, Women’s Hospital, School of Medicine, Zhejiang University, Hangzhou 310006 (China); Department of Obstetrics and Gynaecology, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia V5Z 4H4 (Canada)

    2013-11-01

    Highlights: •HOXA7 regulates MCF7 cell proliferation. •HOXA7 up-regulates ERα expression. •HOXA7 mediates estrogen-induced MCF7 cell proliferation. -- Abstract: Breast cancer is the most common hormone-dependent malignancy in women. Homeobox (HOX) transcription factors regulate many cellular functions, including cell migration, proliferation and differentiation. The aberrant expression of HOX genes has been reported to be associated with human reproductive cancers. Estradiol (E2) and its nuclear receptors, estrogen receptor (ER)-alpha and ER-beta, are known to play critical roles in the regulation of breast cancer cell growth. However, an understanding of the potential relationship between HOXA7 and ER in breast cancer cells is limited. In this study, our results demonstrate that knockdown of HOXA7 in MCF7 cells significantly decreased cell proliferation and ERα expression. In addition, HOXA7 knockdown attenuated E2-induced cell proliferation as well as progesterone receptor (PR) expression. The stimulatory effects of E2 on cell proliferation and PR expression were abolished by co-treatment with ICI 182780, a selective ERα antagonist. In contrast, overexpression of HOXA7 significantly stimulated cell proliferation and ERα expression. Moreover, E2-induced cell proliferation, as well as PR expression, was enhanced by the overexpression of HOXA7. Neither knockdown nor overexpression of HOXA7 affected the ER-beta levels. Our results demonstrate a novel mechanistic role for HOXA7 in modulating breast cancer cell proliferation via regulation of ERα expression. This finding contributes to our understanding of the role HOXA7 plays in regulating the proliferation of ER-positive cancer cells.

  4. Homeobox A7 stimulates breast cancer cell proliferation by up-regulating estrogen receptor-alpha

    International Nuclear Information System (INIS)

    Highlights: •HOXA7 regulates MCF7 cell proliferation. •HOXA7 up-regulates ERα expression. •HOXA7 mediates estrogen-induced MCF7 cell proliferation. -- Abstract: Breast cancer is the most common hormone-dependent malignancy in women. Homeobox (HOX) transcription factors regulate many cellular functions, including cell migration, proliferation and differentiation. The aberrant expression of HOX genes has been reported to be associated with human reproductive cancers. Estradiol (E2) and its nuclear receptors, estrogen receptor (ER)-alpha and ER-beta, are known to play critical roles in the regulation of breast cancer cell growth. However, an understanding of the potential relationship between HOXA7 and ER in breast cancer cells is limited. In this study, our results demonstrate that knockdown of HOXA7 in MCF7 cells significantly decreased cell proliferation and ERα expression. In addition, HOXA7 knockdown attenuated E2-induced cell proliferation as well as progesterone receptor (PR) expression. The stimulatory effects of E2 on cell proliferation and PR expression were abolished by co-treatment with ICI 182780, a selective ERα antagonist. In contrast, overexpression of HOXA7 significantly stimulated cell proliferation and ERα expression. Moreover, E2-induced cell proliferation, as well as PR expression, was enhanced by the overexpression of HOXA7. Neither knockdown nor overexpression of HOXA7 affected the ER-beta levels. Our results demonstrate a novel mechanistic role for HOXA7 in modulating breast cancer cell proliferation via regulation of ERα expression. This finding contributes to our understanding of the role HOXA7 plays in regulating the proliferation of ER-positive cancer cells

  5. The Fto Gene Regulates the Proliferation and Differentiation of Pre-Adipocytes in Vitro

    Directory of Open Access Journals (Sweden)

    Yang Jiao

    2016-02-01

    Full Text Available The highly regulated differentiation and proliferation of pre-adipocytes play a key role in the initiation of obesity. Fat mass and obesity associated (FTO is a novel gene strongly associated with the risk of obesity. A deficiency of FTO may cause growth retardation in addition to fat mass and adipocyte size reduction in vivo. To investigate the potential role of Fto gene on the proliferation and differentiation of pre-adipocytes, we generated Fto-knockdown and overexpressed 3T3-L1 cells. Using numerous proliferation assays our results suggest that Fto knockdown leads to suppression of proliferation, lower mitochondrial membrane potential, less cellular ATP, and decreased and smaller intracellular lipid droplets compared with controls (p < 0.05. Western blot analysis demonstrated that Fto knockdown can significantly suppress peroxisome proliferator-activated receptor gamma (PPARγ and glucose transporter type 4 (GLUT4 expression and inhibit Akt phosphorylation. By contrast, overexpression of Fto had the opposing effect on proliferation, mitochondrial membrane potential, ATP generation, in vitro differentiation, Akt phosphorylation, and PPARγ and GLUT4 expression. Moreover, we demonstrated that Wortmannin, a phosphoinositide 3-kinase (PI3K inhibitor, could inhibit phospho-Akt in Fto overexpressed 3T3-L1 cells. Taken together, the results suggest that Fto regulates the proliferation and differentiation of 3T3-L1 cells via multiple mechanisms, including PPARγ and PI3K/Akt signaling.

  6. The Fto Gene Regulates the Proliferation and Differentiation of Pre-Adipocytes in Vitro.

    Science.gov (United States)

    Jiao, Yang; Zhang, Jingying; Lu, Lunjie; Xu, Jiaying; Qin, Liqiang

    2016-02-01

    The highly regulated differentiation and proliferation of pre-adipocytes play a key role in the initiation of obesity. Fat mass and obesity associated (FTO) is a novel gene strongly associated with the risk of obesity. A deficiency of FTO may cause growth retardation in addition to fat mass and adipocyte size reduction in vivo. To investigate the potential role of Fto gene on the proliferation and differentiation of pre-adipocytes, we generated Fto-knockdown and overexpressed 3T3-L1 cells. Using numerous proliferation assays our results suggest that Fto knockdown leads to suppression of proliferation, lower mitochondrial membrane potential, less cellular ATP, and decreased and smaller intracellular lipid droplets compared with controls (p < 0.05). Western blot analysis demonstrated that Fto knockdown can significantly suppress peroxisome proliferator-activated receptor gamma (PPARγ) and glucose transporter type 4 (GLUT4) expression and inhibit Akt phosphorylation. By contrast, overexpression of Fto had the opposing effect on proliferation, mitochondrial membrane potential, ATP generation, in vitro differentiation, Akt phosphorylation, and PPARγ and GLUT4 expression. Moreover, we demonstrated that Wortmannin, a phosphoinositide 3-kinase (PI3K) inhibitor, could inhibit phospho-Akt in Fto overexpressed 3T3-L1 cells. Taken together, the results suggest that Fto regulates the proliferation and differentiation of 3T3-L1 cells via multiple mechanisms, including PPARγ and PI3K/Akt signaling. PMID:26907332

  7. Myostatin stimulates, not inihibits, C2C12 myoblast proliferation.

    Science.gov (United States)

    Rodgers, Buel D; Wiedeback, Benjamin D; Hoversten, Knut E; Jackson, Melissa F; Walker, Ryan G; Thompson, Thomas B

    2014-03-01

    The immortal C2C12 cell line originates from dystrophic mouse thigh muscle and has been used to study the endocrine control of muscle cell growth, development, and function, including those actions regulated by myostatin. Previous studies suggest that high concentrations of recombinant myostatin generated in bacteria inhibit C2C12 proliferation and differentiation. Recombinant myostatin generated in eukaryotic systems similarly inhibits the proliferation of primary myosatellite cells, but consequently initiates, rather than inhibits, their differentiation and is bioactive at far lower concentrations. Our studies indicate that 2 different sources of recombinant myostatin made in eukaryotes stimulate, not inhibit, C2C12 proliferation. This effect occurred at different cell densities and serum concentrations and in the presence of IGF-I, a potent myoblast mitogen. This stimulatory effect was comparable to that obtained with TGFβ1, a related factor that also inhibits primary myosatellite cell proliferation. Attenuating the myostatin/activin (ie, Acvr2b) and TGFβ1 receptor signaling pathways with the Alk4/5 and Alk5 inhibitors, SB431542 and SB505142, respectively, similarly attenuated proliferation induced by serum, myostatin or TGFβ1 and in a dose-dependent manner. In serum-free medium, both myostatin and TGFβ1 stimulated Smad2 phosphorylation, but not that of Smad3, and a Smad3 inhibitor (SIS3) only inhibited proliferation in cells cultured in high serum. Thus, myostatin and TGFβ1 stimulate C2C12 proliferation primarily via Smad2. These results together question the physiological relevance of the C2C12 model and previous studies using recombinant myostatin generated in bacteria. They also support the alternative use of primary myosatellite cells and recombinant myostatin generated in eukaryotes. PMID:24424069

  8. Phorbol Esters Isolated from Jatropha Meal Induced Apoptosis-Mediated Inhibition in Proliferation of Chang and Vero Cell Lines

    Directory of Open Access Journals (Sweden)

    Syahida Ahmad

    2012-10-01

    Full Text Available The direct feeding of Jatropha meal containing phorbol esters (PEs indicated mild to severe toxicity symptoms in various organs of different animals. However, limited information is available on cellular and molecular mechanism of toxicity caused by PEs present in Jatropha meal. Thus, the present study was conducted to determine the cytotoxic and mode of action of PEs isolated from Jatropha meal using human hepatocyte (Chang and African green monkey kidney (Vero cell lines. The results showed that isolated PEs inhibited cell proliferation in a dose-dependent manner in both cell lines with the CC50 of 125.9 and 110.3 μg/mL, respectively. These values were compatible to that of phorbol 12-myristate 13-acetate (PMA values as positive control i.e., 124.5 and 106.3 μg/mL respectively. Microscopic examination, flow cytometry and DNA fragmentation results confirmed cell death due to apoptosis upon treatment with PEs and PMA at CC50 concentration for 24 h in both cell lines. The Western blot analysis revealed the overexpression of PKC-δ and activation of caspase-3 proteins which could be involved in the mechanism of action of PEs and PMA. Consequently, the PEs isolated form Jatropha meal caused toxicity and induced apoptosis-mediated proliferation inhibition toward Chang and Vero cell lines involving over-expression of PKC-δ and caspase-3 as their mode of actions.

  9. Effects of salinity and temperature on in vitro cell cycle and proliferation of Perkinsus marinus from Brazil.

    Science.gov (United States)

    Queiroga, Fernando Ramos; Marques-Santos, Luis Fernando; DE Medeiros, Isac Almeida; DA Silva, Patrícia Mirella

    2016-04-01

    Field and in vitro studies have shown that high salinities and temperatures promote the proliferation and dissemination of Perkinsus marinus in several environments. In Brazil, the parasite infects native oysters Crassostrea gasar and Crassostrea rhizophorae in the Northeast (NE), where the temperature is high throughout the year. Despite the high prevalence of Perkinsus spp. infection in oysters from the NE of Brazil, no mortality events were reported by oyster farmers to date. The present study evaluated the effects of salinity (5, 20 and 35 psu) and temperature (15, 25 and 35 °C) on in vitro proliferation of P. marinus isolated from a host (C. rhizophorae) in Brazil, for a period of up to 15 days and after the return to the control conditions (22 days; recovery). Different cellular parameters (changes of cell phase's composition, cell density, viability and production of reactive oxygen species) were analysed using flow cytometry. The results indicate that the P. marinus isolate was sensitive to the extreme salinities and temperatures analysed. Only the highest temperature caused lasting cell damage under prolonged exposure, impairing P. marinus recovery, which is likely to be associated with oxidative stress. These findings will contribute to the understanding of the dynamics of perkinsiosis in tropical regions. PMID:26888407

  10. Proliferation assay of mouse embryonic stem (ES) cells exposed to atmospheric-pressure plasmas at room temperature

    International Nuclear Information System (INIS)

    Proliferation assays of mouse embryonic stem (ES) cells have been performed with cell culture media exposed to atmospheric-pressure plasmas (APPs), which generate reactive species in the media at room temperature. It is found that serum in cell culture media functions as a scavenger of highly reactive species and tends to protect cells in the media against cellular damage. On the other hand, if serum is not present in a cell culture medium when it is exposed to APP, the medium becomes cytotoxic and cannot be detoxified by serum added afterwards. Plasma-induced cytotoxic media hinder proliferation of mouse ES cells and may even cause cell death. It is also shown by nuclear magnetic resonance spectroscopy that organic compounds in cell culture media are in general not significantly modified by plasma exposure. These results indicate that if there is no serum in media when they are exposed to APPs, highly reactive species (such as OH radicals) generated in the media by the APP exposure are immediately converted to less reactive species (such as H2O2), which can no longer readily react with serum that is added to the medium after plasma exposure. This study has clearly shown that it is these less reactive species, rather than highly reactive species, that make the medium cytotoxic to mouse ES cells. (paper)

  11. Water Extract of Dolichos lablab Attenuates Hepatic Lipid Accumulation in a Cellular Nonalcoholic Fatty Liver Disease Model.

    Science.gov (United States)

    Im, A-Rang; Kim, Yun Hee; Lee, Hye Won; Song, Kwang Hoon

    2016-05-01

    Nonalcoholic fatty liver disease (NAFLD) is a common chronic liver disease that is rising in prevalence worldwide. Therapeutic strategies for patients with NAFLD are limited by a lack of effective drugs. In this report, we show that Dolichos lablab water extract (DLL-Ex) protects against free fatty acid (FFA)-induced lipid accumulation and attenuates expression of genes involved in lipid droplet accumulation in cellular NAFLD models. The hepatoprotective effects and underlying mechanism of DLL-Ex were assessed using an in vitro cellular model in which NAFLD was simulated by inducing excessive FFA influx into hepatocytes. HepG2 cells were treated with DLL-Ex and FFAs for 24 h, after which intracellular lipid content was observed by using Nile Red and Oil Red O staining. Quantitative real-time polymerase chain reaction was used to measure expression levels of genes related to FFA-mediated cellular energy depletion. Western blotting was used to measure protein levels of phosphorylated c-Jun N-terminal kinase, AMP-activated protein kinase alpha (AMPKα), and peroxisome proliferator-activated receptor γ coactivator 1 alpha. In HepG2 cells, DLL-Ex inhibited expression of CD36, which regulates fatty acid uptake, as well as BODIPY-labeled fatty acid uptake. Additionally, DLL-Ex significantly attenuated FFA-mediated cellular energy depletion and mitochondrial membrane depolarization. Furthermore, DLL-Ex enhanced phosphorylation of AMPK, indicating that AMPK is a critical regulator of DLL-Ex-mediated inhibition of hepatic lipid accumulation, possibly through its antioxidative effect. These results demonstrate that DLL-Ex exerts potent anti-NAFLD activity, suggesting that it could be a potential adjuvant treatment for patients with NAFLD. PMID:27152979

  12. Noninvasive Assessment of Tumor Cell Proliferation in Animal Models

    Directory of Open Access Journals (Sweden)

    Matthias Edinger

    1999-10-01

    Full Text Available Revealing the mechanisms of neoplastic disease and enhancing our ability to intervene in these processes requires an increased understanding of cellular and molecular changes as they occur in intact living animal models. We have begun to address these needs by developing a method of labeling tumor cells through constitutive expression of an optical reporter gene, noninvasively monitoring cellular proliferation in vivo using a sensitive photon detection system. A stable line of HeLa cells that expressed a modified firefly luciferase gene was generated, proliferation of these cells in irradiated severe combined immunodeficiency (SCID mice was monitored. Tumor cells were introduced into animals via subcutaneous, intraperitoneal and intravenous inoculation and whole body images, that revealed tumor location and growth kinetics, were obtained. The number of photons that were emitted from the labeled tumor cells and transmitted through murine tissues was sufficient to detect 1×103 cells in the peritoneal cavity, 1×104 cells at subcutaneous sites and 1×106 circulating cells immediately following injection. The kinetics of cell proliferation, as measured by photon emission, was exponential in the peritoneal cavity and at subcutaneous sites. Intravenous inoculation resulted in detectable colonies of tumor cells in animals receiving more than 1×103 cells. Our demonstrated ability to detect small numbers of tumor cells in living animals noninvasively suggests that therapies designed to treat minimal disease states, as occur early in the disease course and after elimination of the tumor mass, may be monitored using this approach. Moreover, it may be possible to monitor micrometastases and evaluate the molecular steps in the metastatic process. Spatiotemporal analyses of neoplasia will improve the predictability of animal models of human disease as study groups can be followed over time, this method will accelerate development of novel therapeutic

  13. ETOH inhibits embryonic neural stem/precursor cell proliferation via PLD signaling

    International Nuclear Information System (INIS)

    While a mother's excessive alcohol consumption during pregnancy is known to have adverse effects on fetal neural development, little is known about the underlying mechanism of these effects. In order to investigate these mechanisms, we investigated the toxic effect of ethanol (ETOH) on neural stem/precursor cell (NSC) proliferation. In cultures of NSCs, phospholipase D (PLD) is activated following stimulation with epidermal growth factor (EGF) and fibroblast growth factor 2 (FGF2). Exposure of NSCs to ETOH suppresses cell proliferation, while it has no effect on cell death. Phosphatidic acid (PA), which is a signaling messenger produced by PLD, reverses ETOH inhibition of NSC proliferation. Blocking the PLD signal by 1-butanol suppresses the proliferation. ETOH-induced suppression of NSC proliferation and the protective effect of PA for ETOH-induced suppression are mediated through extracellular signal-regulated kinase signaling. These results indicate that exposure to ETOH impairs NSC proliferation by altering the PLD signaling pathway

  14. Vitamin E Supplementation Delays Cellular Senescence In Vitro.

    Science.gov (United States)

    La Fata, Giorgio; Seifert, Nicole; Weber, Peter; Mohajeri, M Hasan

    2015-01-01

    Vitamin E is an important antioxidant that protects cells from oxidative stress-induced damage, which is an important contributor to the progression of ageing. Ageing can be studied in vitro using primary cells reaching a state of irreversible growth arrest called senescence after a limited number of cellular divisions. Generally, the most utilized biomarker of senescence is represented by the expression of the senescence associated β-galactosidase (SA-β-gal). We aimed here to study the possible effects of vitamin E supplementation in two different human primary cell types (HUVECs and fibroblasts) during the progression of cellular senescence. Utilizing an unbiased automated system, based on the detection of the SA-β-gal, we quantified cellular senescence in vitro and showed that vitamin E supplementation reduced the numbers of senescent cells during progression of ageing. Acute vitamin E supplementation did not affect cellular proliferation, whereas it was decreased after chronic treatment. Mechanistically, we show that vitamin E supplementation acts through downregulation of the expression of the cycline dependent kinase inhibitor P21. The data obtained from this study support the antiageing properties of vitamin E and identify possible mechanisms of action that warrant further investigation. PMID:26613084

  15. Vitamin E Supplementation Delays Cellular Senescence In Vitro

    Directory of Open Access Journals (Sweden)

    Giorgio La Fata

    2015-01-01

    Full Text Available Vitamin E is an important antioxidant that protects cells from oxidative stress-induced damage, which is an important contributor to the progression of ageing. Ageing can be studied in vitro using primary cells reaching a state of irreversible growth arrest called senescence after a limited number of cellular divisions. Generally, the most utilized biomarker of senescence is represented by the expression of the senescence associated β-galactosidase (SA-β-gal. We aimed here to study the possible effects of vitamin E supplementation in two different human primary cell types (HUVECs and fibroblasts during the progression of cellular senescence. Utilizing an unbiased automated system, based on the detection of the SA-β-gal, we quantified cellular senescence in vitro and showed that vitamin E supplementation reduced the numbers of senescent cells during progression of ageing. Acute vitamin E supplementation did not affect cellular proliferation, whereas it was decreased after chronic treatment. Mechanistically, we show that vitamin E supplementation acts through downregulation of the expression of the cycline dependent kinase inhibitor P21. The data obtained from this study support the antiageing properties of vitamin E and identify possible mechanisms of action that warrant further investigation.

  16. Effect of Electromagnetic Fields on Proliferation and Differentiation of Cultured Mouse Bone Marrow Mesenchymal Stem Cells

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    In order to study the effects of electromagnetic fields (EMFs) on proliferation, differentiation and intercellular cyclic AMP (cAMP) in mouse bone marrow mesenchymal stem cells (MSCs) in vitro, the mouse bone MSCs were isolated and cultured in vitro. The third passage MSCs were divided into 4 groups and stimulated with EMFs. The cellular proliferation (MTT),the cellular differentiation (alkaline phosphatase activity, ALP), and the intercellular cAMP level were investigated at different time points. The results showed that EMF (50Hz pulse burst 2 mT peak) inhibited the cellular proliferation (P<0.05), enhanced the cellular differentiation (P<0.05), and increased the intercellular cAMP level (P<0.01) in the early time of the stimulation (1-3 days), but the intercellular cAMP level did not increased further in the later days. We are led to conclude that the cAMP may be involved in the mediation of the growth inhibitory and differentiation-inducing signals of specific EMFs in vitro.

  17. Hierarchical Cellular Structures in High-Capacity Cellular Communication Systems

    CERN Document Server

    Jain, R K; Agrawal, N K

    2011-01-01

    In the prevailing cellular environment, it is important to provide the resources for the fluctuating traffic demand exactly in the place and at the time where and when they are needed. In this paper, we explored the ability of hierarchical cellular structures with inter layer reuse to increase the capacity of mobile communication network by applying total frequency hopping (T-FH) and adaptive frequency allocation (AFA) as a strategy to reuse the macro and micro cell resources without frequency planning in indoor pico cells [11]. The practical aspects for designing macro- micro cellular overlays in the existing big urban areas are also explained [4]. Femto cells are inducted in macro / micro / pico cells hierarchical structure to achieve the required QoS cost effectively.

  18. Molecular and cellular mechanisms of adipogenesis

    Directory of Open Access Journals (Sweden)

    Aleksander Dmitrievich Egorov

    2015-03-01

    Full Text Available The main components of metabolic syndrome include insulin resistance, hypertriglyceridemia and arterial hypertension. Obesity is the cause of metabolic syndrome, mainly as a consequence of the endocrine function of adipose tissue. The volume of adipose tissue depends on the size of individual adipocytes and on their number. The number of adipocytes increases as a result of enhanced adipocyte differentiation. The transcriptional cascade that regulates this differentiation has been well studied. The major adipogenic transcription factor peroxisome proliferator-activated receptor gamma is a ligand-activated nuclear receptor with essential roles in adipogenesis. Its ligands are used to treat metabolic syndrome and type 2 diabetes mellitus. The present article describes the basic molecular and cellular mechanisms of adipogenesis and discusses the impact of insulin, glucocorticoids, cyclic adenosine monophosphate-activating agents, nuclear receptors and transcription factors on the process of adipogenesis. New regulatory regions of the genome that are capable of binding multiple transcription factors are described, and the most promising drug targets for the treatment of metabolic syndrome and obesity, including the homeodomain proteins Pbx1 and Prep1, are discussed.

  19. In vivo imaging of cellular proliferation in renal cell carcinoma using 18F-fluorothymidine PET

    Directory of Open Access Journals (Sweden)

    Peter K. Wong

    2014-05-01

    Results: The SUVmax (maximum standardized uptake value mean±SD for FLT in tumour was 2.59±1.27, compared to normal kidney (2.47±0.34. The mean SUVmax for FDG in tumour was similar to FLT (2.60±1.08. There was a significant correlation between FLT uptake and the immunohistochemical marker Ki-67 (r=0.72, P

  20. Protein kinase CK2 and its role in cellular proliferation, development and pathology

    DEFF Research Database (Denmark)

    Guerra, B; Issinger, O G

    1999-01-01

    Protein kinase CK2 is a pleiotropic, ubiquitous and constitutively active protein kinase that can use both ATP and GTP as phosphoryl donors with specificity for serine/threonine residues in the vicinity of acidic amino acids. Recent results show that the enzyme is involved in transcription, signa...

  1. Altered control of cellular proliferation in the absence of mammalian brahma (SNF2alpha).

    OpenAIRE

    Reyes, J C; Barra, J.; Muchardt, C; Camus, A.; Babinet, C; Yaniv, M

    1998-01-01

    The mammalian SWI-SNF complex is an evolutionarily conserved, multi-subunit machine, involved in chromatin remodelling during transcriptional activation. Within this complex, the BRM (SNF2alpha) and BRG1 (SNF2beta) proteins are mutually exclusive subunits that are believed to affect nucleosomal structures using the energy of ATP hydrolysis. In order to characterize possible differences in the function of BRM and BRG1, and to gain further insights into the role of BRM-containing SWI-SNF comple...

  2. Continuum representations of cellular solids

    Energy Technology Data Exchange (ETDEWEB)

    Neilsen, M.K.

    1993-09-01

    Cellular materials consist of interconnected struts or plates which form cells. The struts or plates are constructed from a variety of metals, polymers, ceramics and wood products. Cellular materials are often used in impact limiters for shipping containers to protect the contents from accidental impact events. These materials exhibit a variety of complex behavior when subjected to crushing loads. This research focuses on the development of continuum representations of cellular solids that can be used in the finite element analysis of shipping container accidents. A significant portion of this work is the development of a new methodology to relate localized deformations to appropriate constitutive descriptions. This methodology provides the insight needed to select constitutive descriptions for cellular solids that capture the localized deformations that are observed experimentally. Constitutive relations are developed for two different cellular materials, aluminum honeycomb and polyurethane foam. These constitutive relations are based on plasticity and continuum damage theories. Plasticity is used to describe the permanent deformation exhibited by both aluminum honeycomb and polyurethane foam. Continuum damage is needed to capture the change in elastic parameters due to cracking of the polyurethane cell wall materials. The new constitutive description of polyurethane foam is implemented in both static and dynamic finite element codes, and analytical and numerical predictions are compared with available experimental data.

  3. Prognosis of Different Cellular Generations

    Directory of Open Access Journals (Sweden)

    Preetish Ranjan

    2013-04-01

    Full Text Available Technological advancement in mobile telephony from 1G to 3G, 4G and 5G has a very axiomatic fact that made an entire world a global village. The cellular system employs a different design approach and technology that most commercial radio and television system use. In the cellular system, the service area is divided into cells and a transmitter is designed to serve an individual cell. The system seeks to make efficient use of available channels by using low-power transmitters to allow frequency reuse at a smaller distance. Maximizing the number of times each channel can be reused in a given geographical area is the key to an efficient cellular system design. During the past three decades, the world has seen significant changes in telecommunications industry. There have been some remarkable aspects to the rapid growth in wireless communications, as seen by the large expansion in mobile systems. This paper focuses on “Past, Present & Future of Cellular Telephony” and some light has been thrown upon the technologies of the cellular systems, namely 1G, 2G, 2.5G, 3G and future generations like 4G and 5G systems as well.

  4. Nanoparticles for cells proliferation enhancement

    International Nuclear Information System (INIS)

    The potential of semiconductor nanoparticles as stimulator for avian mesenchyme stem cells proliferation enhancement is demonstrated. The effect is related to nanoparticles polarization due to external ultrasound field resulting in local electrical stimulation. Our preliminary results demonstrates that the number of cells have been increased by 23 % ±2%) in cell cultures under the action of external ultrasound stimulation. Morphological analysis and viability shows no differences between the control group and the group studied. These results suggest the possibility for tissue regeneration enhancement by remote stimulation of implanted semiconductor nanoparticles. (authors)

  5. Fissile material disposition and proliferation risk

    International Nuclear Information System (INIS)

    The proliferation risk of a facility is dependent on the material attractiveness, level of safeguards, and physical protection applied to the material in conjunction with an assessment of the impact of the socioeconomic circumstances and threat environment. Proliferation risk is a complementary extension of proliferation resistance. The authors believe a better determination of nuclear material proliferation can be achieved by establishing the proliferation risk for facilities that contain nuclear material. Developing a method that incorporates the socioeconomic circumstances and threat environment inherent to each country enables a global proliferation assessment. In order to effectively reduce the nuclear danger, a broadly based set of criteria is needed that provides the capability to relatively assess a wide range of disposition options/facilities in different countries and still ensure a global decrease in proliferation risk for plutonium

  6. ADAM17 promotes proliferation of collecting duct kidney epithelial cells through ERK activation and increased glycolysis in polycystic kidney disease.

    Science.gov (United States)

    Beck Gooz, Monika; Maldonado, Eduardo N; Dang, Yujing; Amria, May Y; Higashiyama, Shigeki; Abboud, Hanna E; Lemasters, John J; Bell, P Darwin

    2014-09-01

    Polycystic kidney disease (PKD) is a common genetic disorder leading to cyst formation in the kidneys and other organs that ultimately results in kidney failure and death. Currently, there is no therapy for slowing down or stopping the progression of PKD. In this study, we identified the disintegrin metalloenzyme 17 (ADAM17) as a key regulator of cell proliferation in kidney tissues of conditional knockout Ift88(-/-) mice and collecting duct epithelial cells from Ift88°(rpk) mice, animal models of autosomal recessive polycystic kidney disease (ARPKD). Using Western blotting, an enzyme activity assay, and a growth factor-shedding assay in the presence or absence of the specific ADAM17 inhibitor TMI-005, we show that increased expression and activation of ADAM17 in the cystic kidney and in collecting duct epithelial cells originating from the Ift88°(rpk) mice (designated as PKD cells) lead to constitutive shedding of several growth factors, including heparin-binding EGF-like growth factor (HB-EGF), amphiregulin, and transforming growth factor-α (TGF-α). Increased growth factor shedding induces activation of the EGFR/MAPK/ERK pathway and maintains higher cell proliferation rate in PKD cells compared with control cells. PKD cells also displayed increased lactate formation and extracellular acidification indicative of aerobic glycolysis (Warburg effect), which was blocked by ADAM17 inhibition. We propose that ADAM17 is a key promoter of cellular proliferation in PKD cells by activating the EGFR/ERK axis and a proproliferative glycolytic phenotype. PMID:24899059

  7. miR-194 targets RBX1 gene to modulate proliferation and migration of gastric cancer cells.

    Science.gov (United States)

    Chen, Xiaonan; Wang, Yuanyuan; Zang, Wenqiao; Du, Yuwen; Li, Min; Zhao, Guoqiang

    2015-04-01

    RING box protein1 (RBX1), an essential component of SCF E3 ubiquitin ligases, plays an important role in gastric cancer. In the study, miR-194 and RBX1 expression was evaluated in 76 pairs of gastric tumor and non-tumor tissue samples by qRT-PCR, and clinicopathological characteristics were analyzed. CCK8, transwell assay, wound healing assay, and flow cytometry assay were performed to evaluate the effect of miR-194 on gastric cancer (GC) cellular proliferation, invasion, migration, apoptosis, and cell cycle, respectively. Luciferase reporter assays and Western blotting were used to evaluate whether RBX1 is a direct target of miR-194. The Kaplan-Meier method and log-rank test were used to evaluate the correlation between miR-194 or RBX1 expression and patient survival. Then, we found that miR-194 was significantly downregulated and RBX1 upregulated in GC tissues; both of which showed significant association with tumor size, location, invasion, and tumor node metastasis. Cell proliferation, invasion, and migration were significantly restricted with miR-194 overexpression. miR-194 downregulated RBX1 protein expression, and luciferase assays showed that binding sites in the RBX1 3'UTR were required for miR-194-mediated repression of RBX1, indicating that RBX1 was a direct target of miR-194. Transfection of RBX1 without the 3'UTR restored the miR-194-inhibiting migration function. miR-194 overexpression or RBX1 lowexpression was associated with prolonged survival of GC patients. In conclusion, upregulation of miR-194 can inhibit proliferation, migration, and invasion of GC cells, possibly by targeting RBX1. Aberrant expression of miR-194 and RBX1 is correlated to GC patient survival time. PMID:25412959

  8. Cellular responses to 836 MHz and 1,765 GHz CDMA radiations

    International Nuclear Information System (INIS)

    The effect of radiofrequency (RF) radiation in the cellular phone communication range (836.5 MHz and 1.765 GHz code division multiple access, CDMA) on tumorigenesis and other health effect was measured using the in vitro cell culture system. To determine whether 836.5 MHz or 1.765 GHz CDMA radiations have any genotoxic effects to induce neoplastic transformation, C3H 10T1/2 cells were exposed to either of the above radiations at a specific absorption rate (SAR) of 35.6W/Kg (836.5 MHz) and 38.2 W/kg(1.765 GHz) or sham- exposed at the same time for 7 days. Cells were maintained in incubators and refed with fresh growth medium every 3 days. At this SAR, radiofrequency radiation did not induce neoplastic transformation in vitro. The extent of alteration in the kinetics of cell proliferation indicated no significant differences between RF-radiation- and sham-exposed cells with respect to MTS assay and 8-OHdG. Under this experimental conditions tested, there is no evidence for the induction of genotoxic indices in human and mouse cells exposed in vitro for 7 days to 836.5 MHz or 1.765 GHz RF radiation at SARs of up to 35.6 or 38.2 W/kg

  9. The relationship between cellular adhesion and surface roughness in polystyrene modified by microwave plasma radiation

    Directory of Open Access Journals (Sweden)

    Biazar E

    2011-03-01

    Full Text Available Esmaeil Biazar1, Majid Heidari2, Azadeh Asefnezhad2, Naser Montazeri11Department of Chemistry, Islamic Azad University, Tonekabon Branch, Mazandaran; 2Department of Biomaterial Engineering, Faculty of Biomedical Engineering, Science and Research Branch, Islamic Azad University, Tehran, IranBackground: Surface modification of medical polymers can improve biocompatibility. Pure polystyrene is hydrophobic and cannot provide a suitable environment for cell cultures. The conventional method for surface modification of polystyrene is treatment with plasma. In this study, conventional polystyrene was exposed to microwave plasma treatment with oxygen and argon gases for 30, 60, and 180 seconds.Methods and results: Attenuated total reflection Fourier transform infrared spectra investigations of irradiated samples indicated clearly the presence of functional groups. Atomic force microscopic images of samples irradiated with inert and active gases indicated nanometric surface topography. Samples irradiated with oxygen plasma showed more roughness (31 nm compared with those irradiated with inert plasma (16 nm at 180 seconds. Surface roughness increased with increasing duration of exposure, which could be due to reduction of the contact angle of samples irradiated with oxygen plasma. Contact angle analysis showed reduction in samples irradiated with inert plasma. Samples irradiated with oxygen plasma showed a lower contact angle compared with those irradiated by argon plasma.Conclusion: Cellular investigations with unrestricted somatic stem cells showed better adhesion, cell growth, and proliferation for samples radiated by oxygen plasma with increasing duration of exposure than those of normal samples.Keywords: surface topography, polystyrene, plasma treatment, argon, oxygen

  10. Aging, cellular senescence, and cancer.

    Science.gov (United States)

    Campisi, Judith

    2013-01-01

    For most species, aging promotes a host of degenerative pathologies that are characterized by debilitating losses of tissue or cellular function. However, especially among vertebrates, aging also promotes hyperplastic pathologies, the most deadly of which is cancer. In contrast to the loss of function that characterizes degenerating cells and tissues, malignant (cancerous) cells must acquire new (albeit aberrant) functions that allow them to develop into a lethal tumor. This review discusses the idea that, despite seemingly opposite characteristics, the degenerative and hyperplastic pathologies of aging are at least partly linked by a common biological phenomenon: a cellular stress response known as cellular senescence. The senescence response is widely recognized as a potent tumor suppressive mechanism. However, recent evidence strengthens the idea that it also drives both degenerative and hyperplastic pathologies, most likely by promoting chronic inflammation. Thus, the senescence response may be the result of antagonistically pleiotropic gene action. PMID:23140366

  11. Novel Materials for Cellular Nanosensors

    DEFF Research Database (Denmark)

    Sasso, Luigi

    The monitoring of cellular behavior is useful for the advancement of biomedical diagnostics, drug development and the understanding of a cell as the main unit of the human body. Micro- and nanotechnology allow for the creation of functional devices that enhance the study of cellular dynamics by...... modifications for electrochemical nanosensors for the detection of analytes released from cells. Two type of materials were investigated, each pertaining to the two different aspects of such devices: peptide nanostructures were studied for the creation of cellular sensing substrates that mimic in vivo surfaces...... and that offer advantages of functionalization, and conducting polymers were used as electrochemical sensor surface modifications for increasing the sensitivity towards relevant analytes, with focus on the detection of dopamine released from cells via exocytosis. Vertical peptide nanowires were...

  12. Cellular-based preemption system

    Science.gov (United States)

    Bachelder, Aaron D. (Inventor)

    2011-01-01

    A cellular-based preemption system that uses existing cellular infrastructure to transmit preemption related data to allow safe passage of emergency vehicles through one or more intersections. A cellular unit in an emergency vehicle is used to generate position reports that are transmitted to the one or more intersections during an emergency response. Based on this position data, the one or more intersections calculate an estimated time of arrival (ETA) of the emergency vehicle, and transmit preemption commands to traffic signals at the intersections based on the calculated ETA. Additional techniques may be used for refining the position reports, ETA calculations, and the like. Such techniques include, without limitation, statistical preemption, map-matching, dead-reckoning, augmented navigation, and/or preemption optimization techniques, all of which are described in further detail in the above-referenced patent applications.

  13. Non-proliferation under revision

    International Nuclear Information System (INIS)

    At the 3rd NPT Revision Conference held in Geneva between August 27 and September 21, 1985, the member states to the Treaty reconfirmed their conviction that the agreement had become an essential part in the efforts to secure peace in the world and that is fundamental objectives continued to serve this purpose. Since the ratification in 1968 and the entering into force in 1970 of the Non-proliferation Treaty, the number of member states had risen continually to, at present, 130. In 1975, 92 states in 1980, 114 states had signed the agreement. The three nuclear weapon states, USA, UK, and USSR, are depositary states. France acts as if she had acceded to the Treaty, and the People's Republic of China as the 5th nuclear weapon state seems to take steps in the same direction by voluntarily opening nuclear installations to checks by IAEA inspectors. Incidentally, an effective framework of non-proliferation in the South American region has been created in the Treaty of Tlatelolco. 98% of all nuclear installations in the non-nuclear weapon countries are covered by IAEA safeguards. (orig.)

  14. Negative regulators of cell proliferation

    Science.gov (United States)

    Johnson, T. C.; Spooner, B. S. (Principal Investigator)

    1994-01-01

    Cell proliferation is governed by the influence of both mitogens and inhibitors. Although cell contact has long been thought to play a fundamental role in cell cycling regulation, and negative regulators have long been suspected to exist, their isolation and purification has been complicated by a variety of technical difficulties. Nevertheless, over recent years an ever-expanding list of putative negative regulators have emerged. In many cases, their biological inhibitory activities are consistent with density-dependent growth inhibition. Most likely their interactions with mitogenic agents, at an intracellular level, are responsible for either mitotic arrest or continued cell cycling. A review of naturally occurring cell growth inhibitors is presented with an emphasis on those factors shown to be residents of the cell surface membrane. Particular attention is focused on a cell surface sialoglycopeptide, isolated from intact bovine cerebral cortex cells, which has been shown to inhibit the proliferation of an unusually wide range of target cells. The glycopeptide arrest cells obtained from diverse species, both fibroblasts and epithelial cells, and a broad variety of transformed cells. Signal transduction events and a limited spectrum of cells that are refractory to the sialoglycopeptide have provided insight into the molecular events mediated by this cell surface inhibitor.

  15. Gas Centrifuges and Nuclear Proliferation

    Energy Technology Data Exchange (ETDEWEB)

    Albright, David

    2004-09-15

    Gas centrifuges have been an ideal enrichment method for a wide variety of countries. Many countries have built gas centrifuges to make enriched uranium for peaceful nuclear purposes. Other countries have secretly sought centrifuges to make highly enriched uranium for nuclear weapons. In more recent times, several countries have secretly sought or built gas centrifuges in regions of tension. The main countries that have been of interest in the last two decades have been Pakistan, Iraq, Iran, and North Korea. Currently, most attention is focused on Iran, Pakistan, and North Korea. These states did not have the indigenous abilities to make gas centrifuges, focusing instead on illicit and questionable foreign procurement. The presentation covered the following main sections: Spread of centrifuges through illicit procurement; Role of export controls in stopping proliferation; Increasing the transparency of gas centrifuge programs in non-nuclear weapon states; and, Verified dismantlement of gas centrifuge programs. Gas centrifuges are important providers of low enriched uranium for civil nuclear power reactors. They also pose special nuclear proliferation risks. We all have special responsibilities to prevent the spread of gas centrifuges into regions of tension and to mitigate the consequences of their spread into the Middle East, South Asia, and North Asia.

  16. Adaptive stochastic cellular automata: Applications

    Science.gov (United States)

    Qian, S.; Lee, Y. C.; Jones, R. D.; Barnes, C. W.; Flake, G. W.; O'Rourke, M. K.; Lee, K.; Chen, H. H.; Sun, G. Z.; Zhang, Y. Q.; Chen, D.; Giles, C. L.

    1990-09-01

    The stochastic learning cellular automata model has been applied to the problem of controlling unstable systems. Two example unstable systems studied are controlled by an adaptive stochastic cellular automata algorithm with an adaptive critic. The reinforcement learning algorithm and the architecture of the stochastic CA controller are presented. Learning to balance a single pole is discussed in detail. Balancing an inverted double pendulum highlights the power of the stochastic CA approach. The stochastic CA model is compared to conventional adaptive control and artificial neural network approaches.

  17. Cellular senescence in aging primates.

    Science.gov (United States)

    Herbig, Utz; Ferreira, Mark; Condel, Laura; Carey, Dee; Sedivy, John M

    2006-03-01

    The aging of organisms is characterized by a gradual functional decline of all organ systems. Mammalian somatic cells in culture display a limited proliferative life span, at the end of which they undergo an irreversible cell cycle arrest known as replicative senescence. Whether cellular senescence contributes to organismal aging has been controversial. We investigated telomere dysfunction, a recently discovered biomarker of cellular senescence, and found that the number of senescent fibroblasts increases exponentially in the skin of aging baboons, reaching >15% of all cells in very old individuals. In addition, the same cells contain activated ataxia-telangiectasia mutated kinase and heterochromatinized nuclei, confirming their senescent status. PMID:16456035

  18. Cellular automaton for chimera states

    Science.gov (United States)

    García-Morales, Vladimir

    2016-04-01

    A minimalistic model for chimera states is presented. The model is a cellular automaton (CA) which depends on only one adjustable parameter, the range of the nonlocal coupling, and is built from elementary cellular automata and the majority (voting) rule. This suggests the universality of chimera-like behavior from a new point of view: Already simple CA rules based on the majority rule exhibit this behavior. After a short transient, we find chimera states for arbitrary initial conditions, the system spontaneously splitting into stable domains separated by static boundaries, some synchronously oscillating and the others incoherent. When the coupling range is local, nontrivial coherent structures with different periodicities are formed.

  19. Prognosis of Different Cellular Generations

    OpenAIRE

    Preetish Ranjan; Prabhat Kumar

    2013-01-01

    Technological advancement in mobile telephony from 1G to 3G, 4G and 5G has a very axiomatic fact that made an entire world a global village. The cellular system employs a different design approach and technology that most commercial radio and television system use. In the cellular system, the service area is divided into cells and a transmitter is designed to serve an individual cell. The system seeks to make efficient use of available channels by using low-power transmitters to allow frequen...

  20. Cholesterol induces proliferation of chicken primordial germ cells.

    Science.gov (United States)

    Chen, Dongyang; Chen, Meijuan; Lu, Zhenping; Yang, Mengmeng; Xie, Long; Zhang, Wenxin; Xu, Huiyan; Lu, Kehuan; Lu, Yangqing

    2016-08-01

    Primordial germ cells (PGCs) are the precursors of sperm and eggs and may serve as suitable cells for use in research in developmental biology and transgenic animals. However, the long-term propagation of PGCs in vitro has so far been plagued by the loss of their germ cell characteristics. This is largely because of the scarcity of knowledge concerning cell division and proliferation in these cells and the poor optimization of the culture medium. The sonic hedgehog (SHH) signaling pathway is involved in proliferation of many types of cells, but little is known about its role in chicken PGCs. The results of the current study indicate that the proliferation of chicken PGCs increases significantly when cholesterol, a molecule that facilitates the trafficking of HH ligands, is supplemented in the culture medium. This effect was attenuated when an SHH antagonist, cyclopamine was added, suggesting the involvement of SHH signaling in this process. The characterization of PGCs treated with cholesterol has shown that these cells express germ-cell-related markers and retain their capability to colonize the embryonic gonad after re-introduction to vasculature of stage-15 HH embryos, indicating that proliferation of PGCs induced by cholesterol does not alter the germ cell characteristics of these cells. PMID:27269880

  1. HER2 drives Mucin-like 1 to control proliferation in breast cancer cells

    Science.gov (United States)

    Conley, S J; Bosco, E E; Tice, D A; Hollingsworth, R E; Herbst, R; Xiao, Z

    2016-01-01

    Mucin-like 1 (MUCL1) was first identified as a breast-specific gene over a decade ago. Based on its highly restricted mRNA expression in breast tissue and continued expression during breast tumorigenesis and progression, MUCL1 is an attractive tumor-associated antigen and a potential therapeutic target. However, very little is known about the cellular location, biological functions and regulation of the MUCL1 protein, which will have a major impact on its druggability. Here we describe our efforts to fully characterize the cellular localization of MUCL1, investigate its regulation by key breast cancer oncogenes such as human epidermal growth factor receptor 2 (HER2) and discover its functional roles in breast cancer. Although some mucins are membrane bound, our data indicate that MUCL1 is secreted by some breast cancer cells, whereas others only express high levels of intracellular MUCL1. MUCL1 expression is highest in HER2-amplified breast tumors and inhibiting HER2 activity in tumor cells resulted in a decreased MUCL1 expression. In-depth investigation demonstrated that phosphoinositide3-kinase/Akt pathway, but not Ras/MEK pathway, controls MUCL1 expression downstream of HER2. Phenotypic assays revealed a strong dependence of HER2-positive cells on MUCL1 for cell proliferation. We further identified the mechanism by which MUCL1 regulates cell growth. Knockdown of MUCL1 induced a G1/S phase arrest concomitant with decreased cyclin D and increased p21 and p27 levels. Finally, we investigated the impact of MUCL1 loss on kinase signaling pathways in breast cancer cells through phospho-kinase array profiling. MUCL1 silencing abrogated phospho-focal adhesion kinase (FAK), Jun NH2-terminal kinase (JNK) and c-Jun signals, but not extracellular signal-regulated kinase or Akt pathway activities, thereby pointing to FAK/JNK pathway as the downstream effector of MUCL1 signaling. We are the first to identify an important role for MUCL1 in the proliferation of breast cancer

  2. Simian virus 40 large T antigen's association with the CUL7 SCF complex contributes to cellular transformation.

    Science.gov (United States)

    Kasper, Jocelyn S; Kuwabara, Hiroshi; Arai, Takehiro; Ali, Syed Hamid; DeCaprio, James A

    2005-09-01

    Simian virus 40 large T antigen (T Ag) is capable of immortalizing and transforming rodent cells. The transforming activity of T Ag is due in large part to perturbation of the tumor suppressor proteins p53 and the retinoblastoma (pRB) family members. Inactivation of these tumor suppressors may not be sufficient for T Ag-mediated cellular transformation. It has been shown that T Ag associates with an SCF-like complex that contains a member of the cullin family of E3 ubiquitin ligases, CUL7, as well as SKP1, RBX1, and an F-box protein, FBXW8. We identified T Ag residues 69 to 83 as required for T Ag binding to the CUL7 complex. We demonstrate that delta69-83 T Ag, while it lost its ability to associate with CUL7, retained binding to p53 and pRB family members. In the presence of CUL7, wild-type (WT) T Ag but not delta69-83 T Ag was able to induce proliferation of mouse embryo fibroblasts, an indication of cellular transformation. In contrast, WT and delta69-83 T Ag enabled mouse embryo fibroblasts to proliferate to similarly high densities in the absence of CUL7. Our data suggest that, in addition to p53 and the pRB family members, T Ag serves to bind to and inactivate the growth-suppressing properties of CUL7. In addition, these results imply that, at least in the presence of T Ag, CUL7 may function as a tumor suppressor. PMID:16140746

  3. Cellular Phone Base Stations: Technology and Exposures (invited paper)

    International Nuclear Information System (INIS)

    The principles and practice of cellular radio systems for mobile communications are presented using GSM 1800 as a reference system. In particular, the concepts of small cells and frequency re-use and the components of radio base station technology are described. Public and cellular broadcasting have been widely available for many years and a brief history is given to indicate length of exposure from these sources. National and international guidelines for safe exposure to non-ionising radiation are used by cellular operators to define exclusion zones around transmitting antennas. A methodology for calculating an exclusion zone is described, together with an example for a typical antenna configuration. Estimated levels of exposure near practical base stations are given and comparisons made with other sources of RF radiation. Finally, the digital nature of today's cellular radio systems, such as GSM, are explained and the implications described. (author)

  4. Study on proliferation time and response time for proliferation resistance evaluation

    International Nuclear Information System (INIS)

    'Proliferation time' is one of the proliferation resistance measures adopted by the Generation IV Nuclear Energy Systems International Forum (GIF) Proliferation Resistance and Physical Protection (PR and PP) evaluation methodology. A longer proliferation time would provide the international society with more time to intervene politically in order to dissuade the State from completing its nuclear weapons program. A longer proliferation time would therefore contribute to the enhancement of proliferation resistance of a given nuclear energy system. Two methods are considered for judging whether the proliferation time is long enough: 1) comparison of the proliferation times between a reference nuclear energy system and the subject system, and 2) comparison between the proliferation time and the response time, which can be defined as the time available to the international society to make a political intervention. This paper focuses on the latter method and examines how the response time can be estimated by reviewing prior incidents. (author)

  5. Common cellular events occur during wound healing and organ regeneration in the sea cucumber Holothuria glaberrima

    Directory of Open Access Journals (Sweden)

    García-Arrarás José E

    2007-10-01

    Full Text Available Abstract Background All animals possess some type of tissue repair mechanism. In some species, the capacity to repair tissues is limited to the healing of wounds. Other species, such as echinoderms, posses a striking repair capability that can include the replacement of entire organs. It has been reported that some mechanisms, namely extracellular matrix remodeling, appear to occur in most repair processes. However, it remains unclear to what extent the process of organ regeneration, particularly in animals where loss and regeneration of complex structures is a programmed natural event, is similar to wound healing. We have now used the sea cucumber Holothuria glaberrima to address this question. Results Animals were lesioned by making a 3–5 mm transverse incision between one of the longitudinal muscle pairs along the bodywall. Lesioned tissues included muscle, nerve, water canal and dermis. Animals were allowed to heal for up to four weeks (2, 6, 12, 20, and 28 days post-injury before sacrificed. Tissues were sectioned in a cryostat and changes in cellular and tissue elements during repair were evaluated using classical dyes, immmuohistochemistry and phalloidin labeling. In addition, the temporal and spatial distribution of cell proliferation in the animals was assayed using BrdU incorporation. We found that cellular events associated with wound healing in H. glaberrima correspond to those previously shown to occur during intestinal regeneration. These include: (1 an increase in the number of spherule-containing cells, (2 remodeling of the extracellular matrix, (3 formation of spindle-like structures that signal dedifferentiation of muscle cells in the area flanking the lesion site and (4 intense cellular division occurring mainly in the coelomic epithelium after the first week of regeneration. Conclusion Our data indicate that H. glaberrima employs analogous cellular mechanisms during wound healing and organ regeneration. Thus, it is possible

  6. Seasonal proliferation rates and the capacity to express genes involved in cell cycling and maintenance in response to seasonal and experimental food shortage in Laternula elliptica from King George Island.

    Science.gov (United States)

    Husmann, G; Philipp, E E R; Abele, D

    2016-07-01

    Melting of coastal glaciers at the West Antarctic Peninsula (WAP) causes shorter winter sea ice duration, intensified ice scouring, sediment erosion and surface freshening in summer, which alters coastal productivity and feeding conditions for the benthos. The soft shell clam Laternula elliptica is a fast growing and abundant filter feeder in coastal Antarctica and a key element for bentho-pelagic carbon recycling. Our aim was to assess the cellular growth and maintenance capacity of small and large clams during natural winter food shortage (seasonal sampling) and in response to experimental starvation exposure. We measured tissue specific proliferation rates, the expression of cell cycling genes, and the iron binding protein Le-ferritin in freshly collected specimens in spring (Nov 2008) and at the end of summer (March 2009). For the experimental approach, we focused on 14 cell cycling and metabolic genes using the same animal size groups. Mantle tissue of young bivalves was the only tissue showing accelerated proliferation in summer (1.7% of cells dividing per day in March) compared to 0.4% dividing cells in animals collected in November. In mantle, siphon and adductor muscle proliferation rates were higher in younger compared to older individuals. At transcript level, Le-cyclin D was upregulated in digestive gland of older animals collected in spring (Nov) compared to March indicating initiation of cell proliferation. Likewise, during experimental starvation Le-cyclin D expression increased in large clam digestive gland, whereas Le-cyclin D and the autophagic factor beclin1 decreased in digestive gland of smaller starved clams. The paper corroborates earlier findings of size and age dependent differences in the metabolic response and gene expression patterns in L. elliptica under energetic deprivation. Age structure of shallow water populations can potentially change due to differences in cellular response between young and old animals as environmental stress

  7. Repaglinide at a cellular level

    DEFF Research Database (Denmark)

    Krogsgaard Thomsen, M; Bokvist, K; Høy, M;

    2002-01-01

    To investigate the hormonal and cellular selectivity of the prandial glucose regulators, we have undertaken a series of experiments, in which we characterised the effects of repaglinide and nateglinide on ATP-sensitive potassium ion (KATP) channel activity, membrane potential and exocytosis in ra...

  8. Cellular signalling properties in microcircuits

    DEFF Research Database (Denmark)

    Toledo-Rodriguez, Maria; El Manira, Abdeljabbar; Wallén, Peter; Svirskis, Gytis; Hounsgaard, Jørn

    2005-01-01

    Molecules and cells are the signalling elements in microcircuits. Recent studies have uncovered bewildering diversity in postsynaptic signalling properties in all areas of the vertebrate nervous system. Major effort is now being invested in establishing the specialized signalling properties at th...... cellular and molecular levels in microcircuits in specific brain regions. This review is part of the TINS Microcircuits Special Feature....

  9. Quantum Cloning by Cellular Automata

    OpenAIRE

    D'Ariano, G. M.; Macchiavello, C.; M. Rossi

    2012-01-01

    We introduce a quantum cellular automaton that achieves approximate phase-covariant cloning of qubits. The automaton is optimized for 1-to-2N economical cloning. The use of the automaton for cloning allows us to exploit different foliations for improving the performance with given resources.

  10. Analysis of cellular manufacturing systems

    NARCIS (Netherlands)

    Heragu, Sunderesh; Meng, Gang; Zijm, Henk; Ommeren, van Jan-Kees

    2001-01-01

    In this paper, we present an open queuing network modeling approach to estimate performance measures of a cellular manufacturing layout. It is assumed a layout and production data for a planning period of specified length are available. The production data takes into account, processing and handli

  11. MUS81 is associated with cell proliferation and cisplatin sensitivity in serous ovarian cancer.

    Science.gov (United States)

    Xie, Suhong; Zheng, Hui; Wen, Xuemei; Sun, Jiajun; Wang, Yanchun; Gao, Xiang; Guo, Lin; Lu, Renquan

    2016-08-01

    The dysfunction of DNA damage repair (DDR) pathway contributes to tumorigenesis and drug-resistance in cancer. MUS81 is a member of the conserved xeroderma pigmentosum group F (XPF) family protein of endonucleases, which is important to the DDR pathway. However, the role of MUS81 in the development of ovarian cancer remains uncertain. To explore the expression of MUS81 and its association to serous ovarian cancer (SOC), 43 biopsies of SOC patients were detected by qRT-PCR, and 29 specimens were further performed by immunohistochemistry analysis. Here, we observed that MUS81 was over-expressed in SOC tissues at both transcript and protein levels, and the expression level of MUS81 protein in ovarian cancer cell lines was also higher than that in human normal ovarian surface epithelial cell line (HOSEpiC). We also found that down-regulation of MUS81 expression in ovarian cancer cells inhibited cell proliferation and colony formation ability, and influenced cell cycle progression. Moreover, inhibition of MUS81 expression induced cellular senescence and enhanced the antitumor effect of cisplatin. Down-regulation of MUS81 expression could suppress the growth and development of SOC. These results indicate that MUS81 might play important roles in the progression of SOC and influence the antitumor effect of cisplatin. PMID:27255997

  12. Transcription factor genes essential for cell proliferation and replicative lifespan in budding yeast

    Energy Technology Data Exchange (ETDEWEB)

    Kamei, Yuka; Tai, Akiko; Dakeyama, Shota; Yamamoto, Kaori; Inoue, Yamato; Kishimoto, Yoshifumi; Ohara, Hiroya; Mukai, Yukio, E-mail: y_mukai@nagahama-i-bio.ac.jp

    2015-07-31

    Many of the lifespan-related genes have been identified in eukaryotes ranging from the yeast to human. However, there is limited information available on the longevity genes that are essential for cell proliferation. Here, we investigated whether the essential genes encoding DNA-binding transcription factors modulated the replicative lifespan of Saccharomyces cerevisiae. Heterozygous diploid knockout strains for FHL1, RAP1, REB1, and MCM1 genes showed significantly short lifespan. {sup 1}H-nuclear magnetic resonance analysis indicated a characteristic metabolic profile in the Δfhl1/FHL1 mutant. These results strongly suggest that FHL1 regulates the transcription of lifespan related metabolic genes. Thus, heterozygous knockout strains could be the potential materials for discovering further novel lifespan genes. - Highlights: • Involvement of yeast TF genes essential for cell growth in lifespan was evaluated. • The essential TF genes, FHL1, RAP1, REB1, and MCM1, regulate replicative lifespan. • Heterozygous deletion of FHL1 changes cellular metabolism related to lifespan.

  13. Human NTH1 physically interacts with p53 and proliferating cell nuclear antigen

    International Nuclear Information System (INIS)

    Thymine glycol (Tg) is one of predominant oxidative DNA lesions caused by ionizing radiation and other oxidative stresses. Human NTH1 is a bifunctional enzyme with DNA glycosylase and AP lyase activities and removes Tg as the first step of base excision repair (BER). We have searched for the factors interacting with NTH1 by using a pull-down assay and found that GST-NTH1 fusion protein precipitates proliferating cell nuclear antigen (PCNA) and p53 as well as XPG from human cell-free extracts. GST-NTH1 also bound to recombinant FLAG-tagged XPG, PCNA, and (His)6-tagged p53 proteins, indicating direct protein-protein interaction between those proteins. Furthermore, His-p53 and FLAG-XPG, but not PCNA, stimulated the Tg DNA glycosylase/AP lyase activity of GST-NTH1 or NTH1. These results provide an insight into the positive regulation of BER reaction and also suggest a possible linkage between BER of Tg and other cellular mechanisms

  14. Mechanistic contribution of electroconductive hydroxyapatite-titanium disilicide composite on the alignment and proliferation of cells.

    Science.gov (United States)

    Kumar, A; Nune, K C; Basu, B; Misra, Rdk

    2016-05-01

    We elucidate here the mechanistic contribution of a novel electroconductive hydroxyapatite-20 wt.% titanium disilicide (HA-TiSi2) composite system in favorably modulating osteoblast functions in relation to the monolithic HA. The higher electrical conductivity of HA-TiSi2(σDC ∼ 67.117 ± 3.57 S/m) in comparison to glass sample effectively guided the electroactive myoblast, leading to their significant alignment and proliferation. This favorable behavior is attributed to the formation of small electrochemical cells between HA and TiSi2phase, which produce a small electric field, directing the electroactive myoblast to migrate and grow in a particular direction. In contrast, no impact of TiSi2on osteoblast function was observed because of their inability to respond to small electric field. However, thein vitrobioactivity in simulated body fluid indicated the nucleation and growth of apatite crystals. Moreover, in the context of load-bearing capability, the presence of 20 wt.% TiSi2in HA led to increase in the fracture toughness by ∼100%. This study underscores the effectiveness of HA-TiSi2in favorably modulating the cellular activity, myoblast in particular. PMID:26945809

  15. Cell proliferation and migration during early development of a symbiotic scleractinian coral.

    Science.gov (United States)

    Lecointe, Agathe; Domart-Coulon, Isabelle; Paris, Alain; Meibom, Anders

    2016-05-25

    In scleractinian reef-building corals, patterns of cell self-renewal, migration and death remain virtually unknown, limiting our understanding of cellular mechanisms underlying initiation of calcification, and ontogenesis of the endosymbiotic dinoflagellate relationship. In this study, we pulse-labelled the coral Stylophora pistillata for 24 h with BrdU at four life stages (planula, early metamorphosis, primary polyp and adult colony) to investigate coral and endosymbiont cell proliferation during development, while simultaneously recording TUNEL-positive (i.e. apoptotic) nuclei. In the primary polyp, the fate of BrdU-labelled cells was tracked during a 3-day chase. The pharynx and gastrodermis were identified as the most proliferative tissues in the developing polyp, and BrdU-labelled cells accumulated in the surface pseudostratified epithelium and the skeletogenic calicodermis during the chase, revealing cell migration to these epithelia. Surprisingly, the lowest cell turnover was recorded in the calicodermis at all stages, despite active, ongoing skeletal deposition. In dinoflagellate symbionts, DNA synthesis was systematically higher than coral host gastrodermis, especially in planula and early metamorphosis. The symbiont to host cell ratio remained constant, however, indicating successive post-mitotic control mechanisms by the host of its dinoflagellate density in early life stages, increasingly shifting to apoptosis in the growing primary polyp. PMID:27194695

  16. Transcription factor genes essential for cell proliferation and replicative lifespan in budding yeast

    International Nuclear Information System (INIS)

    Many of the lifespan-related genes have been identified in eukaryotes ranging from the yeast to human. However, there is limited information available on the longevity genes that are essential for cell proliferation. Here, we investigated whether the essential genes encoding DNA-binding transcription factors modulated the replicative lifespan of Saccharomyces cerevisiae. Heterozygous diploid knockout strains for FHL1, RAP1, REB1, and MCM1 genes showed significantly short lifespan. 1H-nuclear magnetic resonance analysis indicated a characteristic metabolic profile in the Δfhl1/FHL1 mutant. These results strongly suggest that FHL1 regulates the transcription of lifespan related metabolic genes. Thus, heterozygous knockout strains could be the potential materials for discovering further novel lifespan genes. - Highlights: • Involvement of yeast TF genes essential for cell growth in lifespan was evaluated. • The essential TF genes, FHL1, RAP1, REB1, and MCM1, regulate replicative lifespan. • Heterozygous deletion of FHL1 changes cellular metabolism related to lifespan

  17. Regulation of Peroxisome Proliferator-Activated Receptors by E6-Associated Protein

    Directory of Open Access Journals (Sweden)

    Lakshmi Gopinathan

    2008-01-01

    Full Text Available Peroxisome proliferator-activated receptors (PPARs are nuclear receptors (NRs that regulate genes involved in lipid and glucose metabolism. PPAR activity is regulated by interactions with cofactors and of interest are cofactors with ubiquitin ligase activity. The E6-associated protein (E6-AP is an E3 ubiquitin ligase that affects the activity of other NRs, although its effects on PPARs have not been examined. E6-AP inhibited the ligand-independent transcriptional activity of PPARα and PPARβ, with marginal effects on PPARγ, and decreased basal mRNA levels of PPARα target genes. Inhibition of PPARα activity required the ubiquitin ligase function of E6-AP, but occurred in a proteasome-independent manner. PPARα interacted with E6-AP, and in mice treated with PPARα agonist clofibrate, mRNA and protein levels of E6-AP were increased in wildtype, but not in PPARα null mice, indicating a PPARα-dependent regulation. These studies suggest coordinate regulation of E6-AP and PPARα, and contribute to our understanding of the role of PPARs in cellular metabolism.

  18. Proton magnetic resonance spectroscopy reflects cellular proliferative activity in astrocytomas

    International Nuclear Information System (INIS)

    We examined whether proton magnetic resonance spectroscopy (MRS) could provide accurate information on histological grade and cell proliferation in astrocytomas. We studied 23 patients with astrocytomas: five grade II, 10 grade III and eight with grade IV (glioblastoma multiforme). We performed proton MRS and determined the Ki-67 labeling index (LI), a tumour proliferation marker, in the same areas of the astrocytomas, and examined the statistical relationship between proton MRS and Ki-67 LI. The N-acetylaspartate (NAA)/creatine-phosphocreatine (Cr) and NAA/choline (Cho)-containing compound ratios were always significantly lower and the Cho/Cr ratios significantly higher than those for normal brain. The Cho/Cr ratio correlated positively and the NAA/Cho ratio inversely with Ki-67 LI. These findings suggest that the Cho signal in proton MRS reflects cellular proliferation. In Kaplan-Meier survival analysis, there was no significant difference between high (> 2.0, 14 cases) and low (< 2.0, 9 cases) Cho/cr ratio groups. (orig.)

  19. Patterns and Cellular Mechanisms of Arm Regeneration in Adult Starfish Asterias rollestoni Bell

    Institute of Scientific and Technical Information of China (English)

    FAN Tingjun; FAN Xianyuan; DU Yutang; SUN Wenjie; ZHANG Shaofeng; LI Jiaxin

    2011-01-01

    To understand the mechanisms of starfish regeneration,the arms of adult starfish Asterias rollestoni Bell were amputated and their regeneration pattems and cellular mechanisms were studied.It was found that cells in the outer epidermis and inner parietal peritoneum near the end of the stump began to dedifferentiate 4d after amputation.The dedifferentiated cells in the outer epidermis proliferated,migrated to the wound site and formed a thickened pre-epidermis which would then re-differentiate gradually into mature epidermis.The new parietal peritoneum formed on the coelomic side of wound might be from the curvely elongated parietal peritoneum,resulting from the dedifferentiated and proliferated cells by extension.Afterwards,the proliferated cells made the outer epidermis and inner parietal peritoneum invaginate into the interior dermis and formed blastema-like structures together with induced dedifferentiated dermal cells.Most interestingly,the arm regeneration in A.rollestoni was achieved synchronously by de novo arm-bud formation and growth,and arm-stump elongation.The crucial aspects of arm-bud formation included cell dedifferentiation,proliferation and migration,while those of arm-stump elongation included cell dedifferentiation,proliferation,invagination,and arm-wall-across blastema-like structure formation.The unique pattern and cellular mechanisms of amputated arm regeneration make it easier to understand the rapid regeneration process of adult starfish.This study may lay solid foundations for the research into molecular mechanisms of echinoderm regeneration.

  20. Effect of MWCNT surface and chemical modification on in vitro cellular response

    International Nuclear Information System (INIS)

    The aim of this study was to evaluate the impact of multi-walled carbon nanotubes (MWCNTs with diameter in the range of 10–30 nm) before and after chemical surface functionalisation on macrophages response. The study has shown that the detailed analysis of the physicochemical properties of this particular form of carbon nanomaterial is a crucial issue to interpret properly its impact on the cellular response. Effects of carbon nanotubes (CNTs) characteristics, including purity, dispersity, chemistry and dimension upon the nature of the cell environment–material interaction were investigated. Various techniques involving electron microscopy (SEM, TEM), infrared spectroscopy (FTIR), inductively coupled plasma optical emission spectrometry, X-ray photoelectron spectroscopy have been employed to evaluate the physicochemical properties of the materials. The results demonstrate that the way of CNT preparation prior to biological tests has a fundamental impact on their behavior, cell viability and the nature of cell–nanotube interaction. Chemical functionalisation of CNTs in an acidic ambient (MWCNT-Fs) facilitates interaction with cells by two possible mechanisms, namely, endocytosis/phagocytosis and by energy-independent passive process. The results indicate that MWCNT-F in macrophages may decrease the cell proliferation process by interfering with the mitotic apparatus without negative consequences on cell viability. On the contrary, the as-prepared MWCNTs, without any surface treatment produce the least reduction in cell proliferation with reference to control, and the viability of cells exposed to this sample was substantially reduced with respect to control. A possible explanation of such a phenomenon is the presence of MWCNT’s agglomerates surrounded by numerous cells releasing toxic substances.

  1. Disrupted cell cycle arrest and reduced proliferation in corneal fibroblasts from GCD2 patients: A potential role for altered autophagy flux

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Seung-il; Dadakhujaev, Shorafidinkhuja; Maeng, Yong-Sun; Ahn, So-yeon; Kim, Tae-im [Department of Ophthalmology, Severance Hospital, Yonsei University College of Medicine, Seoul (Korea, Republic of); Corneal Dystrophy Research Institute, Yonsei University College of Medicine, Seoul (Korea, Republic of); Kim, Eung Kweon, E-mail: eungkkim@yuhs.ac [Department of Ophthalmology, Severance Hospital, Yonsei University College of Medicine, Seoul (Korea, Republic of); Corneal Dystrophy Research Institute, Yonsei University College of Medicine, Seoul (Korea, Republic of); BK21 Plus Project for Medical Science and Severance Biomedical Science Institute, Yonsei University College of Medicine, Seoul (Korea, Republic of)

    2015-01-02

    Highlights: • Reduced cell proliferation in granular corneal dystrophy type 2. • Abnormal cell cycle arrest by defective autophagy. • Decreased Cyclin A1, B1, and D1 in Atg7 gene knockout cells. • Increase in p16 and p27 expressions were observed in Atg7 gene knockout cells. - Abstract: This study investigates the role of impaired proliferation, altered cell cycle arrest, and defective autophagy flux of corneal fibroblasts in granular corneal dystrophy type 2 (GCD2) pathogenesis. The proliferation rates of homozygous (HO) GCD2 corneal fibroblasts at 72 h, 96 h, and 120 h were significantly lower (1.102 ± 0.027, 1.397 ± 0.039, and 1.527 ± 0.056, respectively) than those observed for the wild-type (WT) controls (1.441 ± 0.029, 1.758 ± 0.043, and 2.003 ± 0.046, respectively). Flow cytometry indicated a decreased G{sub 1} cell cycle progression and the accumulation of cells in the S and G{sub 2}/M phases in GCD2 cells. These accumulations were associated with decreased levels of Cyclin A1, B1, and E1, and increased expression of p16 and p27. p21 and p53 expression was also significantly lower in GCD2 cells compared to the WT. Interestingly, treatment with the autophagy flux inhibitor, bafilomycin A{sub 1}, resulted in similarly decreased Cyclin A1, B1, D1, and p53 expression in WT fibroblasts. Furthermore, similar findings, including a decrease in Cyclin A1, B1, and D1 and an increase in p16 and p27 expression were observed in autophagy-related 7 (Atg7; known to be essential for autophagy) gene knockout cells. These data provide new insight concerning the role of autophagy in cell cycle arrest and cellular proliferation, uncovering a number of novel therapeutic possibilities for GCD2 treatment.

  2. Disrupted cell cycle arrest and reduced proliferation in corneal fibroblasts from GCD2 patients: A potential role for altered autophagy flux

    International Nuclear Information System (INIS)

    Highlights: • Reduced cell proliferation in granular corneal dystrophy type 2. • Abnormal cell cycle arrest by defective autophagy. • Decreased Cyclin A1, B1, and D1 in Atg7 gene knockout cells. • Increase in p16 and p27 expressions were observed in Atg7 gene knockout cells. - Abstract: This study investigates the role of impaired proliferation, altered cell cycle arrest, and defective autophagy flux of corneal fibroblasts in granular corneal dystrophy type 2 (GCD2) pathogenesis. The proliferation rates of homozygous (HO) GCD2 corneal fibroblasts at 72 h, 96 h, and 120 h were significantly lower (1.102 ± 0.027, 1.397 ± 0.039, and 1.527 ± 0.056, respectively) than those observed for the wild-type (WT) controls (1.441 ± 0.029, 1.758 ± 0.043, and 2.003 ± 0.046, respectively). Flow cytometry indicated a decreased G1 cell cycle progression and the accumulation of cells in the S and G2/M phases in GCD2 cells. These accumulations were associated with decreased levels of Cyclin A1, B1, and E1, and increased expression of p16 and p27. p21 and p53 expression was also significantly lower in GCD2 cells compared to the WT. Interestingly, treatment with the autophagy flux inhibitor, bafilomycin A1, resulted in similarly decreased Cyclin A1, B1, D1, and p53 expression in WT fibroblasts. Furthermore, similar findings, including a decrease in Cyclin A1, B1, and D1 and an increase in p16 and p27 expression were observed in autophagy-related 7 (Atg7; known to be essential for autophagy) gene knockout cells. These data provide new insight concerning the role of autophagy in cell cycle arrest and cellular proliferation, uncovering a number of novel therapeutic possibilities for GCD2 treatment

  3. Chronic hypoxia promotes pulmonary artery endothelial cell proliferation through H2O2-induced 5-lipoxygenase.

    Directory of Open Access Journals (Sweden)

    Kristi M Porter

    Full Text Available Pulmonary Hypertension (PH is a progressive disorder characterized by endothelial dysfunction and proliferation. Hypoxia induces PH by increasing vascular remodeling. A potential mediator in hypoxia-induced PH development is arachidonate 5-Lipoxygenase (ALOX5. While ALOX5 metabolites have been shown to promote pulmonary vasoconstriction and endothelial cell proliferation, the contribution of ALOX5 to hypoxia-induced proliferation remains unknown. We hypothesize that hypoxia exposure stimulates HPAEC proliferation by increasing ALOX5 expression and activity. To test this, human pulmonary artery endothelial cells (HPAEC were cultured under normoxic (21% O2 or hypoxic (1% O2 conditions for 24-, 48-, or 72 hours. In a subset of cells, the ALOX5 inhibitor, zileuton, or the 5-lipoxygenase activating protein inhibitor, MK-886, was administered during hypoxia exposure. ALOX5 expression was measured by qRT-PCR and western blot and HPAEC proliferation was assessed. Our results demonstrate that 24 and 48 hours of hypoxia exposure have no effect on HPAEC proliferation or ALOX5 expression. Seventy two hours of hypoxia significantly increases HPAEC ALOX5 expression, hydrogen peroxide (H2O2 release, and HPAEC proliferation. We also demonstrate that targeted ALOX5 gene silencing or inhibition of the ALOX5 pathway by pharmacological blockade attenuates hypoxia-induced HPAEC proliferation. Furthermore, our findings indicate that hypoxia-induced increases in cell proliferation and ALOX5 expression are dependent on H2O2 production, as administration of the antioxidant PEG-catalase blocks these effects and addition of H2O2 to HPAEC promotes proliferation. Overall, these studies indicate that hypoxia exposure induces HPAEC proliferation by activating the ALOX5 pathway via the generation of H2O2.

  4. Natural Products as Tools for Defining How Cellular Metabolism Influences Cellular Immune and Inflammatory Function during Chronic Infection

    Directory of Open Access Journals (Sweden)

    Erica S. Lovelace

    2015-11-01

    Full Text Available Chronic viral infections like those caused by hepatitis C virus (HCV and human immunodeficiency virus (HIV cause disease that establishes an ongoing state of chronic inflammation. While there have been tremendous improvements towards curing HCV with directly acting antiviral agents (DAA and keeping HIV viral loads below detection with antiretroviral therapy (ART, there is still a need to control inflammation in these diseases. Recent studies indicate that many natural products like curcumin, resveratrol and silymarin alter cellular metabolism and signal transduction pathways via enzymes such as adenosine monophosphate kinase (AMPK and mechanistic target of rapamycin (mTOR, and these pathways directly influence cellular inflammatory status (such as NF-κB and immune function. Natural products represent a vast toolkit to dissect and define how cellular metabolism controls cellular immune and inflammatory function.

  5. Proliferation resistance fuel cycle technology

    International Nuclear Information System (INIS)

    The issues of dual use in nuclear technology are analysed for nuclear fuel cycle with special focus on uranium enrichment and spent fuel reprocessing which are considered as the most sensitive components in terms of vulnerability to diversion. Technical alternatives to mitigrate the vulnerability, as has been analysed in depth during the NASAP and INFCE era in the late seventies, are reviewed to characterize the DUPIC fuel cycle alternative. On the other hand, the new realities in nuclear energy including the disposition of weapon materials as a legacy of cold war are recast in an angle of nuclear proliferation resistance and safeguards with a discussion on the concept of spent fuel standard concept and its compliance with the DUPIC fuel cycle technology. (author)

  6. Proliferation resistance fuel cycle technology

    Energy Technology Data Exchange (ETDEWEB)

    Lee, J. S.; Ko, W. I

    1999-02-01

    The issues of dual use in nuclear technology are analysed for nuclear fuel cycle with special focus on uranium enrichment and spent fuel reprocessing which are considered as the most sensitive components in terms of vulnerability to diversion. Technical alternatives to mitigrate the vulnerability, as has been analysed in depth during the NASAP and INFCE era in the late seventies, are reviewed to characterize the DUPIC fuel cycle alternative. On the other hand, the new realities in nuclear energy including the disposition of weapon materials as a legacy of cold war are recast in an angle of nuclear proliferation resistance and safeguards with a discussion on the concept of spent fuel standard concept and its compliance with the DUPIC fuel cycle technology. (author)

  7. Overexpression of HDAC1 induces cellular senescence by Sp1/PP2A/pRb pathway

    Energy Technology Data Exchange (ETDEWEB)

    Chuang, Jian-Ying [Department of Pharmacology, National Cheng-Kung University, Tainan 701, Taiwan (China); Hung, Jan-Jong, E-mail: petehung@mail.ncku.edu.tw [Department of Pharmacology, National Cheng-Kung University, Tainan 701, Taiwan (China); Institute of Bioinformatics and Biosignal Transduction, National Cheng-Kung University, Tainan 701, Taiwan (China)

    2011-04-15

    Highlights: {yields} Overexpression of HDAC1 induces Sp1 deacetylation and raises Sp1/p300 complex formation to bind to PP2Ac promoter. {yields} Overexpression of HDAC1 strongly inhibits the phosphorylation of pRb through up-regulation of PP2A. {yields} Overexpressed HDAC1 restrains cell proliferaction and induces cell senescence though a novel Sp1/PP2A/pRb pathway. -- Abstract: Senescence is associated with decreased activities of DNA replication, protein synthesis, and cellular division, which can result in deterioration of cellular functions. Herein, we report that the growth and division of tumor cells were significantly repressed by overexpression of histone deacetylase (HDAC) 1 with the Tet-off induced system or transient transfection. In addition, HDAC1 overexpression led to senescence through both an accumulation of hypophosphorylated active retinoblastoma protein (pRb) and an increase in the protein level of protein phosphatase 2A catalytic subunit (PP2Ac). HDAC1 overexpression also increased the level of Sp1 deacetylation and elevated the interaction between Sp1 and p300, and subsequently that Sp1/p300 complex bound to the promoter of PP2Ac, thus leading to induction of PP2Ac expression. Similar results were obtained in the HDAC1-Tet-off stable clone. Taken together, these results indicate that HDAC1 overexpression restrained cell proliferation and induced premature senescence in cervical cancer cells through a novel Sp1/PP2A/pRb pathway.

  8. Alterations in cellular energy metabolism associated with the antiproliferative effects of the ATM inhibitor KU-55933 and with metformin.

    Science.gov (United States)

    Zakikhani, Mahvash; Bazile, Miguel; Hashemi, Sina; Javeshghani, Shiva; Avizonis, Daina; St Pierre, Julie; Pollak, Michael N

    2012-01-01

    KU-55933 is a specific inhibitor of the kinase activity of the protein encoded by Ataxia telangiectasia mutated (ATM), an important tumor suppressor gene with key roles in DNA repair. Unexpectedly for an inhibitor of a tumor suppressor gene, KU-55933 reduces proliferation. In view of prior preliminary evidence suggesting defective mitochondrial function in cells of patients with Ataxia Telangiectasia (AT), we examined energy metabolism of cells treated with KU-55933. The compound increased AMPK activation, glucose uptake and lactate production while reducing mitochondrial membrane potential and coupled respiration. The stimulation of glycolysis by KU-55933 did not fully compensate for the reduction in mitochondrial functions, leading to decreased cellular ATP levels and energy stress. These actions are similar to those previously described for the biguanide metformin, a partial inhibitor of respiratory complex I. Both compounds decreased mitochondrial coupled respiration and reduced cellular concentrations of fumarate, malate, citrate, and alpha-ketogluterate. Succinate levels were increased by KU-55933 levels and decreased by metformin, indicating that the effects of ATM inhibition and metformin are not identical. These observations suggest a role for ATM in mitochondrial function and show that both KU-55933 and metformin perturb the TCA cycle as well as oxidative phosphorylation. PMID:23185347

  9. Alterations in cellular energy metabolism associated with the antiproliferative effects of the ATM inhibitor KU-55933 and with metformin.

    Directory of Open Access Journals (Sweden)

    Mahvash Zakikhani

    Full Text Available KU-55933 is a specific inhibitor of the kinase activity of the protein encoded by Ataxia telangiectasia mutated (ATM, an important tumor suppressor gene with key roles in DNA repair. Unexpectedly for an inhibitor of a tumor suppressor gene, KU-55933 reduces proliferation. In view of prior preliminary evidence suggesting defective mitochondrial function in cells of patients with Ataxia Telangiectasia (AT, we examined energy metabolism of cells treated with KU-55933. The compound increased AMPK activation, glucose uptake and lactate production while reducing mitochondrial membrane potential and coupled respiration. The stimulation of glycolysis by KU-55933 did not fully compensate for the reduction in mitochondrial functions, leading to decreased cellular ATP levels and energy stress. These actions are similar to those previously described for the biguanide metformin, a partial inhibitor of respiratory complex I. Both compounds decreased mitochondrial coupled respiration and reduced cellular concentrations of fumarate, malate, citrate, and alpha-ketogluterate. Succinate levels were increased by KU-55933 levels and decreased by metformin, indicating that the effects of ATM inhibition and metformin are not identical. These observations suggest a role for ATM in mitochondrial function and show that both KU-55933 and metformin perturb the TCA cycle as well as oxidative phosphorylation.

  10. Diverse Functions of VDUP1 in Cell Proliferation, Differentiation, and Diseases

    Institute of Scientific and Technical Information of China (English)

    Sang Yong Kim; Hyun-Woo Suh; Jin Woong Chung; Suk-Ran Yoon; Inpyo Choi

    2007-01-01

    Vitamin D3 up-regulated protein 1 (VDUP1) is a multifunctional protein involved in maintaining cellular homeostasis. VDUP1 is induced by a variety of stresses. Inversely, VDUP1 is often reduced in various tumor tissues and cell lines. Over-expression of VDUP1 inhibits cell proliferation through cell cycle arrest. VDUP1 interacts with thioredoxin (Trx) and negatively regulates the expression and antioxidant function of Trx which is involved in redox regulation. VDUP1-/- mice are more susceptible to carcinogenesis than wild-type mice and are defective in establishing immune system including the development and function of natural killer cells. Furthermore, VDUP1-/-mice show impaired Kreb cycle-mediated fatty acid utilization. In this review, we have discussed the multifunctional roles of VDUP1 in diverse cellular responses, in particular its relation to proliferation, apoptosis,differentiation, and diseases such as cancer and stress-related diseases.

  11. Swelling-activated ion channels: functional regulation in cell-swelling, proliferation and apoptosis

    DEFF Research Database (Denmark)

    Stutzin, A; Hoffmann, E K

    2006-01-01

    physiological control. Thus, cell volume is under a tight and dynamic control and abnormal cell volume regulation will ultimately lead to severe cellular dysfunction, including alterations in cell proliferation and cell death. This review describes the different swelling-activated ion channels that participate...... as key players in the maintenance of normal steady-state cell volume, with particular emphasis on the intracellular signalling pathways responsible for their regulation during hypotonic stress, cell proliferation and apoptosis.......Cell volume regulation is one of the most fundamental homeostatic mechanisms and essential for normal cellular function. At the same time, however, many physiological mechanisms are associated with regulatory changes in cell size meaning that the set point for cell volume regulation is under...

  12. Cellular responses in primary epidermal cultures from oncorhynchus mykiss following the combined exposure of ionising radiation and a heavy metal

    International Nuclear Information System (INIS)

    Mechanisms of toxicant action on biological systems are difficult to identify when more than one contaminant is involved due to potential synergistic and antagonistic effects. There is a general paucity of research into the effect of radiation exposure in tandem with common environmental contaminants due to the inherent difficulties involved. In vitro cell cultures are particularly suited to the study of toxic mechanisms due to their proximity to toxic modes of action and the absence of the multiple defence mechanisms present in intact organisms. Primary cell cultures are particularly beneficial in this area of research as they still maintain many of their tissue specific functions. The objective of this study was to distinguish different mechanisms of cell death (growth arrest, apoptosis, primary and secondary necrosis and proliferation), following combination exposure to ionising radiation and a heavy metal (ZnCl2). The model system employed was a primary cell culture of rainbow trout (Oncorhynchus mykiss) epidermal tissue which has been previously used to study the effects of various environmental agents in this laboratory. Apoptosis and necrosis were quantified morphologically while proliferation was assessed immuno-cyto-chemically using an anti PCNA (proliferating cell nuclear antigen) antibody. While radiation doses up to and including 10 Gy had no effect on growth, exposure to ZnCl2 produced a significant dose dependent reduction in growth (10, 50, 75, 100 and 200 ppm ZnCl2). Preliminary results indicate no significant effect on growth following a combined exposure of 5 Gy + 50 ppm ZnCl2. These results may have important implications for understanding the mechanisms underlying cellular responses to multiple contaminant exposures. (author)

  13. Nuclear energy and nuclear weapons proliferation

    International Nuclear Information System (INIS)

    A summary of the report dispatched in the middle of 1978 by the Atlantic Council of United States, organized by North American citizens, is presented. The report considers the relation between the production of nucleoelectric energy and the capacity of proliferation of nuclear weapons. The factors which affect the grade of proliferation risk represented by the use of nuclear energy in the world comparing this risk with the proliferation risks independently of nuclear energy, are examined. (M.C.K.)

  14. Proliferation resistance: issues, initiatives and evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Pilat, Joseph F [Los Alamos National Laboratory

    2009-01-01

    The vision of a nuclear renaissance has highlighted the issue of proliferation resistance. The prospects for a dramatic growth in nuclear power may depend on the effectiveness of, and the resources devoted to, plans to develop and implement technologies and approaches that strengthen proliferation resistance. The GenIV International Forum (GIF) and others have devoted attention and resources to proliferation resistance. However, the hope of finding a way to make the peaceful uses of nuclear energy resistant to proliferation has reappeared again and again in the history of nuclear power with little practical consequence. The concept of proliferation resistance has usually focused on intrinsic (technological) as opposed to extrinsic (institutional) factors. However, if there are benefits that may yet be realized from reactors and other facilities designed to minimize proliferation risks, it is their coupling with effective safeguards and other nonproliferation measures that likely will be critical. Proliferation resistance has also traditionally been applied only to state threats. Although there are no technologies that can wholly eliminate the risk of proliferation by a determined state, technology can play a limited role in reducing state threats and perhaps in eliminating many non-state threats. These and other issues are not academic. They affect efforts to evaluate proliferation resistance, including the methodology developed by GIF's Proliferation Resistance and Physical Protection (PR&PP) Working Group as well as the proliferation resistance initiatives that are being pursued or may be developed in the future. This paper will offer a new framework for thinking about proliferation resistance issues, including the ways the output of the methodology could be developed to inform the decisions that states, the International Atomic Energy (IAEA) and others will have to make in order to fully realize the promise of a nuclear renaissance.

  15. PROLIFERATION AS A KEY EVENT IN DEVELOPMENTAL TOXICITY: "CHEMICAL SCREENING IN HUMAN NEURAL STEM CELLS USING HIGH CONTENT IMAGING

    Science.gov (United States)

    New toxicity testing approaches will rely on in vitro assays to assess chemical effects at the cellular and molecular level. Cell proliferation is imperative to normal development, and chemical disruption of this process can be detrimental to the organism. As part of an effort to...

  16. Modeling Nuclear Proliferation : Expanding Input Variable Sets

    International Nuclear Information System (INIS)

    Quantitative tools have been developed to analyze and nuclear proliferation events. However, the results from the current models show weaknesses in the model. This work is an attempt to improve upon existing models by adding new variables based on the understanding of nuclear proliferation scenarios. In this study, two more variables were added to existing dataset to enhance the nuclear proliferation prediction. The results showed enhancement of modeling capability for some countries, but some limitations still exist. Future work will include by adding new variables and improving database to further enhance proliferation modeling capability

  17. Strengthening the non proliferation regime: French views

    International Nuclear Information System (INIS)

    3 main issues can be identified in the French policy concerning the backing of non proliferation: 1) responding resolutely to proliferation crises, 2) reinforcing substantive efforts to prevent and impede proliferation, and 3) strengthening the non-proliferation regime. The first issue is very important because combating proliferation is vital to the security of all. Concerning the second issue, France attaches particular importance to strengthening specific measures to prevent and check proliferation. Let me mention a few proposals that we put forward: exports need to be controlled more effectively, proliferation activities have to be criminalized, or the development of proliferation-resistant technologies should be supported. Concerning the third issue it means the strengthening of the non-proliferation regime, France proposes several means: -) aiming at the universalization of the additional protocol; -) ensuring that the Agency continues to have sufficient human, financial and technical resources to fulfill its verification mission effectively; -) encouraging the IAEA to make full use of the authority available to it; -) enhancing the use of information relevant to the delivery of the IAEA mandate; and -) sharing more accurate information concerning the breaches of commitments that happen. The paper is followed by the slides of the presentation. (A.C.)

  18. The handbook of nuclear non-proliferation

    International Nuclear Information System (INIS)

    This report analyzed international non-proliferation regime preventing from spread of nuclear weapon. This report took review from the historical background of non-proliferation regime to the recent changes and current status. It is here divided into multilateral and bilateral regime. First of all, this report dealt four multilateral treaties concluded for international non-proliferation such as NPT, NWFZ, CTBT and others. And international organization and regimes concerned with non-proliferation are also analyzed focused on UN, IAEA, ZC and NSG, regional safeguards system and international conferences. In addition, this report reviewed the nuclear cooperation agreement related with Korea which is a important tool for bilateral regime

  19. Can light water reactors be proliferation resistant?

    International Nuclear Information System (INIS)

    per MWe compared to GCR (though HWRs make the lowest Pu per MWe). For the same power, LWRs produce the lowest Pu per year compared to both GCRs and HWRs. The Pu grade of discharged fuel of LWRs is much less than that of GCRs (though equal to HWRs). Therefore, in normal commercial operation, LWRs could be considered as a better non-proliferation option compared to GCRs. In addition, the change of mode of operation to produce weapon-grade Pu or more Pu quantity would be easier to detect for LWRs than for GCRs. This is mainly due to the fact that GCRs can be re-fuelled on-load (i.e. while the reactor is in operation), whereas LWRs should be shutdown first and reactor vessel should be opened, which are easier indicators to be monitored. How LWRs could be more resistant to proliferation? Currently there are close to 200 LWRs under the IAEA safeguards regime. Standard safeguards measures are implemented at these reactors to assure no diversion of declared nuclear material and peaceful use of these reactors for power production. Increasing the confidence level in such assurance might be needed on the basis of particular agreements. The measures to increase the confidence level could be summarized in the following headings: i. Non-proliferation commitment (e.g. ratification of comprehensive safeguards agreements and Additional Protocol, successful completion of verification of initial inventory, positive safeguards conclusion for the declared nuclear material and absence of undeclared nuclear material and activities, ..etc). ii. Application of different safeguards measures (e.g. use of unannounced inspections, complementary access, remote and environmental monitoring systems, advanced NDA for spent fuel, verification of irradiated non-fuel items ...etc.). iii. Additional specific agreements (e.g. limitation of out of core inventory, delivery of enriched fuel, restriction of spent fuel reprocessing, ..etc.) iv. LWR design specifications' (e.g. related to fuel assemblies

  20. FoxP3 inhibits proliferation and induces apoptosis of gastric cancer cells by activating the apoptotic signaling pathway

    International Nuclear Information System (INIS)

    Highlights: ► The article revealed FoxP3 gene function in gastric cancer firstly. ► Present the novel roles of FoxP3 in inhibiting proliferation and promoting apoptosis in gastric cancer cells. ► Overexpression of FoxP3 increased proapoptotic molecules and repressed antiapoptotic molecules. ► Silencing of FoxP3 reduced the expression of proapoptotic genes, such as PARP, caspase-3 and caspase-9. ► FoxP3 is sufficient for activating the apoptotic signaling pathway. -- Abstract: Forkhead Box Protein 3 (FoxP3) was identified as a key transcription factor to the occurring and function of the regulatory T cells (Tregs). However, limited evidence indicated its function in tumor cells. To elucidate the precise roles and underlying molecular mechanism of FoxP3 in gastric cancer (GC), we examined the expression of FoxP3 and the consequences of interfering with FoxP3 gene in human GC cell lines, AGS and MKN45, by multiple cellular and molecular approaches, such as immunofluorescence, gene transfection, CCK-8 assay, clone formation assay, TUNEL assay, Flow cytometry, immunoassay and quantities polymerase chain reaction (PCR). As a result, FoxP3 was expressed both in nucleus and cytoplasm of GC cells. Up-regulation of FoxP3 inhibited cell proliferation and promoted cell apoptosis. Overexpression of FoxP3 increased the protein and mRNA levels of proapoptotic molecules, such as poly ADP-ribose polymerase1 (PARP), caspase-3 and caspase-9, and repressed the expression of antiapoptotic molecules, such as cellular inhibitor of apoptosis-1 (c-IAP1) and the long isoform of B cell leukemia/lymphoma-2 (Bcl-2). Furthermore, silencing of FoxP3 by siRNA in GC cells reduced the expression of proapoptotic genes, such as PARP, caspase-3 and caspase-9. Collectively, our findings identify the novel roles of FoxP3 in inhibiting proliferation and inducing apoptosis in GC cells by regulating apoptotic signaling, which could be a promising therapeutic approach for gastric cancer.

  1. FoxP3 inhibits proliferation and induces apoptosis of gastric cancer cells by activating the apoptotic signaling pathway

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Gui-Fen [Department of Gastroenterology, Zhongshan Hospital, Fudan University, Shanghai (China); Chen, Shi-Yao, E-mail: shiyao_chen@163.com [Department of Gastroenterology, Zhongshan Hospital, Fudan University, Shanghai (China); Endoscopy Center, Zhongshan Hospital, Fudan University, Shanghai (China); Sun, Zhi-Rong [Department of Anesthesiology, Cancer Center, Fudan University, Shanghai (China); Miao, Qing; Liu, Yi-Mei; Zeng, Xiao-Qing; Luo, Tian-Cheng [Department of Gastroenterology, Zhongshan Hospital, Fudan University, Shanghai (China); Ma, Li-Li; Lian, Jing-Jing [Endoscopy Center, Zhongshan Hospital, Fudan University, Shanghai (China); Song, Dong-Li [Biomedical Research Center, Zhongshan Hospital, Fudan University, Shanghai (China)

    2013-01-11

    Highlights: Black-Right-Pointing-Pointer The article revealed FoxP3 gene function in gastric cancer firstly. Black-Right-Pointing-Pointer Present the novel roles of FoxP3 in inhibiting proliferation and promoting apoptosis in gastric cancer cells. Black-Right-Pointing-Pointer Overexpression of FoxP3 increased proapoptotic molecules and repressed antiapoptotic molecules. Black-Right-Pointing-Pointer Silencing of FoxP3 reduced the expression of proapoptotic genes, such as PARP, caspase-3 and caspase-9. Black-Right-Pointing-Pointer FoxP3 is sufficient for activating the apoptotic signaling pathway. -- Abstract: Forkhead Box Protein 3 (FoxP3) was identified as a key transcription factor to the occurring and function of the regulatory T cells (Tregs). However, limited evidence indicated its function in tumor cells. To elucidate the precise roles and underlying molecular mechanism of FoxP3 in gastric cancer (GC), we examined the expression of FoxP3 and the consequences of interfering with FoxP3 gene in human GC cell lines, AGS and MKN45, by multiple cellular and molecular approaches, such as immunofluorescence, gene transfection, CCK-8 assay, clone formation assay, TUNEL assay, Flow cytometry, immunoassay and quantities polymerase chain reaction (PCR). As a result, FoxP3 was expressed both in nucleus and cytoplasm of GC cells. Up-regulation of FoxP3 inhibited cell proliferation and promoted cell apoptosis. Overexpression of FoxP3 increased the protein and mRNA levels of proapoptotic molecules, such as poly ADP-ribose polymerase1 (PARP), caspase-3 and caspase-9, and repressed the expression of antiapoptotic molecules, such as cellular inhibitor of apoptosis-1 (c-IAP1) and the long isoform of B cell leukemia/lymphoma-2 (Bcl-2). Furthermore, silencing of FoxP3 by siRNA in GC cells reduced the expression of proapoptotic genes, such as PARP, caspase-3 and caspase-9. Collectively, our findings identify the novel roles of FoxP3 in inhibiting proliferation and inducing apoptosis

  2. Ganglioside-Dependent Neural Stem Cell Proliferation in Alzheimer’s Disease Model Mice

    OpenAIRE

    Koon, Noah A.; Itokazu, Yutaka; Yu, Robert K.

    2015-01-01

    The aggregation and formation of amyloid plaques by amyloid β-peptides (Aβs) is believed to be one of the pathological hallmarks of Alzheimer’s disease (AD). Intriguingly, Aβs have also been shown to possess proliferative effects on neural stem cells (NSCs). Many essential cellular processes in NSCs, such as fate determination and proliferation, are heavily influenced by cell surface glycoconjugates, including gangliosides. It has recently been shown that Aβ1-42 alters several key glycosyltra...

  3. Circulatory shear flow alters the viability and proliferation of circulating colon cancer cells

    OpenAIRE

    Rong Fan; Travis Emery; Yongguo Zhang; Yuxuan Xia; Jun Sun; Jiandi Wan

    2016-01-01

    During cancer metastasis, circulating tumor cells constantly experience hemodynamic shear stress in the circulation. Cellular responses to shear stress including cell viability and proliferation thus play critical roles in cancer metastasis. Here, we developed a microfluidic approach to establish a circulatory microenvironment and studied circulating human colon cancer HCT116 cells in response to a variety of magnitude of shear stress and circulating time. Our results showed that cell viabili...

  4. NG2 expression in glioblastoma identifies an actively proliferating population with an aggressive molecular signature

    OpenAIRE

    Al-Mayhani, M. Talal F.; Grenfell, Richard; Narita, Masashi; Piccirillo, Sara; Kenney-Herbert, Emma; Fawcett, James W.; Collins, V. Peter; Ichimura, Koichi; Watts, Colin

    2011-01-01

    Glioblastoma multiforme (GBM) is the most common type of primary brain tumor and a highly malignant and heterogeneous cancer. Current conventional therapies fail to eradicate or curb GBM cell growth. Hence, exploring the cellular and molecular basis of GBM cell growth is vital to develop novel therapeutic approaches. Neuroglia (NG)-2 is a transmembrane proteoglycan expressed by NG2+ progenitors and is strongly linked to cell proliferation in the normal brain. By using NG2 as a biomarker we id...

  5. TORC1 is required to balance cell proliferation and cell death in planarians

    OpenAIRE

    Tu, Kimberly C; Pearson, Bret J.; Alvarado, Alejandro Sánchez

    2012-01-01

    Multicellular organisms are equipped with cellular mechanisms that enable them to replace differentiated cells lost to normal physiological turnover, injury, and for some such as planarians, even amputation. This process of tissue homeostasis is generally mediated by adult stem cells (ASCs), tissue-specific stem cells responsible for maintaining anatomical form and function. To do so, ASCs must modulate the balance between cell proliferation, i.e. in response to nutrients, and that of cell de...

  6. Selenium in Bone Health: Roles in Antioxidant Protection and Cell Proliferation

    OpenAIRE

    Huawei Zeng; Cao, Jay J; Combs, Gerald F

    2013-01-01

    Selenium (Se) is an essential trace element for humans and animals, and several findings suggest that dietary Se intake may be necessary for bone health. Such findings may relate to roles of Se in antioxidant protection, enhanced immune surveillance and modulation of cell proliferation. Elucidation of the mechanisms by which Se supports these cellular processes can lead to a better understanding of the role of this nutrient in normal bone metabolism. This article reviews the current knowledge...

  7. Symbiotic lactobacilli stimulate gut epithelial proliferation via Nox-mediated generation of reactive oxygen species

    OpenAIRE

    Jones, Rheinallt M.; Luo, Liping; Ardita, Courtney S.; Richardson, Arena N; Kwon, Young Man; Mercante, Jeffrey W; Alam, Ashfaqul; Gates, Cymone L; Wu, Huixia; Swanson, Phillip A.; Lambeth, J. David; Patricia W Denning; Neish, Andrew S.

    2013-01-01

    The resident prokaryotic microbiota of the metazoan gut elicits profound effects on the growth and development of the intestine. However, the molecular mechanisms of symbiotic prokaryotic–eukaryotic cross-talk in the gut are largely unknown. It is increasingly recognized that physiologically generated reactive oxygen species (ROS) function as signalling secondary messengers that influence cellular proliferation and differentiation in a variety of biological systems. Here, we report that comme...

  8. Interactions between Human Liver Fatty Acid Binding Protein and Peroxisome Proliferator Activated Receptor Selective Drugs

    OpenAIRE

    Tony Velkov

    2013-01-01

    Fatty acid binding proteins (FABPs) act as intracellular shuttles for fatty acids as well as lipophilic xenobiotics to the nucleus, where these ligands are released to a group of nuclear receptors called the peroxisome proliferator activated receptors (PPARs). PPAR mediated gene activation is ultimately involved in maintenance of cellular homeostasis through the transcriptional regulation of metabolic enzymes and transporters that target the activating ligand. Here we show that liver- (L-) FA...

  9. PI3K/AKT and ERK regulate retinoic acid-induced neuroblastoma cellular differentiation

    Energy Technology Data Exchange (ETDEWEB)

    Qiao, Jingbo [Department of Pediatric Surgery, Vanderbilt University Medical Center, Nashville, TN 37232 (United States); Paul, Pritha; Lee, Sora [Department of Pediatric Surgery, Vanderbilt University Medical Center, Nashville, TN 37232 (United States); Department of Cancer Biology, Vanderbilt University Medical Center, Nashville, TN 37232 (United States); Qiao, Lan; Josifi, Erlena; Tiao, Joshua R. [Department of Pediatric Surgery, Vanderbilt University Medical Center, Nashville, TN 37232 (United States); Chung, Dai H., E-mail: dai.chung@vanderbilt.edu [Department of Pediatric Surgery, Vanderbilt University Medical Center, Nashville, TN 37232 (United States); Department of Cancer Biology, Vanderbilt University Medical Center, Nashville, TN 37232 (United States)

    2012-08-03

    Highlights: Black-Right-Pointing-Pointer Retinoic acid (RA) induces neuroblastoma cells differentiation, which is accompanied by G0/G1 cell cycle arrest. Black-Right-Pointing-Pointer RA resulted in neuroblastoma cell survival and inhibition of DNA fragmentation; this is regulated by PI3K pathway. Black-Right-Pointing-Pointer RA activates PI3K and ERK1/2 pathway; PI3K pathway mediates RA-induced neuroblastoma cell differentiation. Black-Right-Pointing-Pointer Upregulation of p21 is necessary for RA-induced neuroblastoma cell differentiation. -- Abstract: Neuroblastoma, the most common extra-cranial solid tumor in infants and children, is characterized by a high rate of spontaneous remissions in infancy. Retinoic acid (RA) has been known to induce neuroblastoma differentiation; however, the molecular mechanisms and signaling pathways that are responsible for RA-mediated neuroblastoma cell differentiation remain unclear. Here, we sought to determine the cell signaling processes involved in RA-induced cellular differentiation. Upon RA administration, human neuroblastoma cell lines, SK-N-SH and BE(2)-C, demonstrated neurite extensions, which is an indicator of neuronal cell differentiation. Moreover, cell cycle arrest occurred in G1/G0 phase. The protein levels of cyclin-dependent kinase inhibitors, p21 and p27{sup Kip}, which inhibit cell proliferation by blocking cell cycle progression at G1/S phase, increased after RA treatment. Interestingly, RA promoted cell survival during the differentiation process, hence suggesting a potential mechanism for neuroblastoma resistance to RA therapy. Importantly, we found that the PI3K/AKT pathway is required for RA-induced neuroblastoma cell differentiation. Our results elucidated the molecular mechanism of RA-induced neuroblastoma cellular differentiation, which may be important for developing novel therapeutic strategy against poorly differentiated neuroblastoma.

  10. Cellular and molecular mechanisms of HGF/Met in the cardiovascular system.

    Science.gov (United States)

    Gallo, Simona; Sala, Valentina; Gatti, Stefano; Crepaldi, Tiziana

    2015-12-01

    Met tyrosine kinase receptor, also known as c-Met, is the HGF (hepatocyte growth factor) receptor. The HGF/Met pathway has a prominent role in cardiovascular remodelling after tissue injury. The present review provides a synopsis of the cellular and molecular mechanisms underlying the effects of HGF/Met in the heart and blood vessels. In vivo, HGF/Met function is particularly important for the protection of the heart in response to both acute and chronic insults, including ischaemic injury and doxorubicin-induced cardiotoxicity. Accordingly, conditional deletion of Met in cardiomyocytes results in impaired organ defence against oxidative stress. After ischaemic injury, activation of Met provides strong anti-apoptotic stimuli for cardiomyocytes through PI3K (phosphoinositide 3-kinase)/Akt and MAPK (mitogen-activated protein kinase) cascades. Recently, we found that HGF/Met is also important for autophagy regulation in cardiomyocytes via the mTOR (mammalian target of rapamycin) pathway. HGF/Met induces proliferation and migration of endothelial cells through Rac1 (Ras-related C3 botulinum toxin substrate 1) activation. In fibroblasts, HGF/Met antagonizes the actions of TGFβ1 (transforming growth factor β1) and AngII (angiotensin II), thus preventing fibrosis. Moreover, HGF/Met influences the inflammatory response of macrophages and the immune response of dendritic cells, indicating its protective function against atherosclerotic and autoimmune diseases. The HGF/Met axis also plays an important role in regulating self-renewal and myocardial regeneration through the enhancement of cardiac progenitor cells. HGF/Met has beneficial effects against myocardial infarction and endothelial dysfunction: the cellular and molecular mechanisms underlying repair function in the heart and blood vessels are common and include pro-angiogenic, anti-inflammatory and anti-fibrotic actions. Thus administration of HGF or HGF mimetics may represent a promising therapeutic agent for the

  11. Polychaetes as environmental indicators revisited

    International Nuclear Information System (INIS)

    The utilization of polychaetes in descriptive ecology is reviewed in the light of recent research especially concerning the biota hard bottom environments. Polychaetes, often linked in the past to the concept of opportunistic species able to proliferate after an increase in organic matter, have played an important role especially with regard to impacted soft-bottom habitats. Increased knowledge of the group, suggests that not only opportunistic species can be utilised as indicators, so that these organisms can be disengaged from the old concept of opportunistic taxa. Moreover, recent researches conducted on this group allowed demonstrating as surrogacy is not always applicable. Among polychaetes inhabiting hard bottom environment, the analysis of family Syllidae appears particularly promising. Studied conducted in our laboratory demonstrated as syllid species decrease in abundance or completely disappear under varying sources of negative impact. The distribution of species also appeared indicative in underlying effects of marine protected areas (MPA) functioning, or in describing different climatic areas within biogeographical sectors. It is obvious that good results can only be obtained on the basis of good taxonomic resolution. We suggested that, in monitoring studies, operational time could be optimized not only by working at a higher-level on the whole invertebrate data set, but by also selecting a particularly indicative group and working at fine level

  12. Polychaetes as environmental indicators revisited

    Energy Technology Data Exchange (ETDEWEB)

    Giangrande, Adriana [Department of Biological and Environmental Sciences and Technology, University of Lecce, Marine Biological Station, 73100 Lecce (Italy)]. E-mail: gianadri@ilenic.unile.it; Licciano, Margherita [Department of Biological and Environmental Sciences and Technology, University of Lecce, Marine Biological Station, 73100 Lecce (Italy); Musco, Luigi [Department of Biological and Environmental Sciences and Technology, University of Lecce, Marine Biological Station, 73100 Lecce (Italy)

    2005-11-15

    The utilization of polychaetes in descriptive ecology is reviewed in the light of recent research especially concerning the biota hard bottom environments. Polychaetes, often linked in the past to the concept of opportunistic species able to proliferate after an increase in organic matter, have played an important role especially with regard to impacted soft-bottom habitats. Increased knowledge of the group, suggests that not only opportunistic species can be utilised as indicators, so that these organisms can be disengaged from the old concept of opportunistic taxa. Moreover, recent researches conducted on this group allowed demonstrating as surrogacy is not always applicable. Among polychaetes inhabiting hard bottom environment, the analysis of family Syllidae appears particularly promising. Studied conducted in our laboratory demonstrated as syllid species decrease in abundance or completely disappear under varying sources of negative impact. The distribution of species also appeared indicative in underlying effects of marine protected areas (MPA) functioning, or in describing different climatic areas within biogeographical sectors. It is obvious that good results can only be obtained on the basis of good taxonomic resolution. We suggested that, in monitoring studies, operational time could be optimized not only by working at a higher-level on the whole invertebrate data set, but by also selecting a particularly indicative group and working at fine level.

  13. Composite alginate gels for tunable cellular microenvironment mechanics

    Science.gov (United States)

    Khavari, Adele; Nydén, Magnus; Weitz, David A.; Ehrlicher, Allen J.

    2016-01-01

    The mechanics of the cellular microenvironment can be as critical as biochemistry in directing cell behavior. Many commonly utilized materials derived from extra-cellular-matrix create excellent scaffolds for cell growth, however, evaluating the relative mechanical and biochemical effects independently in 3D environments has been difficult in frequently used biopolymer matrices. Here we present 3D sodium alginate hydrogel microenvironments over a physiological range of stiffness (E = 1.85 to 5.29 kPa), with and without RGD binding sites or collagen fibers. We use confocal microscopy to measure the growth of multi-cellular aggregates (MCAs), of increasing metastatic potential in different elastic moduli of hydrogels, with and without binding factors. We find that the hydrogel stiffness regulates the growth and morphology of these cell clusters; MCAs grow larger and faster in the more rigid environments similar to cancerous breast tissue (E = 4–12 kPa) as compared to healthy tissue (E = 0.4–2 kpa). Adding binding factors from collagen and RGD peptides increases growth rates, and change maximum MCA sizes. These findings demonstrate the utility of these independently tunable mechanical/biochemistry gels, and that mechanical confinement in stiffer microenvironments may increase cell proliferation. PMID:27484403

  14. Composite alginate gels for tunable cellular microenvironment mechanics

    Science.gov (United States)

    Khavari, Adele; Nydén, Magnus; Weitz, David A.; Ehrlicher, Allen J.

    2016-08-01

    The mechanics of the cellular microenvironment can be as critical as biochemistry in directing cell behavior. Many commonly utilized materials derived from extra-cellular-matrix create excellent scaffolds for cell growth, however, evaluating the relative mechanical and biochemical effects independently in 3D environments has been difficult in frequently used biopolymer matrices. Here we present 3D sodium alginate hydrogel microenvironments over a physiological range of stiffness (E = 1.85 to 5.29 kPa), with and without RGD binding sites or collagen fibers. We use confocal microscopy to measure the growth of multi-cellular aggregates (MCAs), of increasing metastatic potential in different elastic moduli of hydrogels, with and without binding factors. We find that the hydrogel stiffness regulates the growth and morphology of these cell clusters; MCAs grow larger and faster in the more rigid environments similar to cancerous breast tissue (E = 4–12 kPa) as compared to healthy tissue (E = 0.4–2 kpa). Adding binding factors from collagen and RGD peptides increases growth rates, and change maximum MCA sizes. These findings demonstrate the utility of these independently tunable mechanical/biochemistry gels, and that mechanical confinement in stiffer microenvironments may increase cell proliferation.

  15. Myelin-phagocytosing macrophages modulate autoreactive T cell proliferation

    Directory of Open Access Journals (Sweden)

    Hellings Niels

    2011-07-01

    with their cognate antigen, indicating that myelin-phagocytosing macrophages have dual effects depending on the specificity of surrounding lymphocytes. Conclusions Collectively our data show that myelin phagocytosis leads to an altered macrophage function that inhibits lymphocyte proliferation. Additionally, results from this study indicate that myelin-phagocytosing macrophages fulfill a dual role in vivo. On one hand they aggravate autoimmunity by activating myelin-reactive lymphocytes and on the other hand they suppress lymphocyte reactivity by producing NO.

  16. Climate Change, Nuclear Power and Nuclear Proliferation: Magnitude Matters

    International Nuclear Information System (INIS)

    Integrated energy, environment and economics modeling suggests that worldwide electrical energy use will increase from 2.4 TWe today to ∼12 TWe in 2100. It will be challenging to provide 40% of this electrical power from combustion with carbon sequestration, as it will be challenging to provide 30% from renewable energy sources derived from natural energy flows. Thus nuclear power may be needed to provide ∼30%, 3600 GWe, by 2100. Calculations of the associated stocks and flows of uranium, plutonium and minor actinides indicate that the proliferation risks at mid-century, using current light-water reactor technology, are daunting. There are institutional arrangements that may be able to provide an acceptable level of risk mitigation, but they will be difficult to implement. If a transition is begun to fast-spectrum reactors at mid-century, without a dramatic change in the proliferation risks of such systems, at the end of the century global nuclear proliferation risks are much greater, and more resistant to mitigation. Fusion energy, if successfully demonstrated to be economically competitive, would provide a source of nuclear power with much lower proliferation risks than fission.

  17. Mechanism of Suppression on Proliferation of QGY Cell by Oxaliplatin

    Institute of Scientific and Technical Information of China (English)

    HE Song; ZUO Guo-qing; ZHANG Yan; TANG Wei-xue; LIU Chang-an

    2007-01-01

    Objective: To observe the effects of oxaliplatin(L-OHP) on proliferation of human hepatoma cell line QGY in vitro and to investigate the mechanism. Methods: The inhibition of proliferation in QGY cell was assayed by MTT-test. Morphologic changes were observed under light microscope and electronic microscope. Distribution of cell cycle and apoptosis were analyzed using flow cytometry. The expressions of cell cycle proteins and apoptosis-associated proteins were detected with immuno-histochemical technique. Results: Oxaliplatin could inhibit the proliferation of QGY cells and the inhibition depended on the exposure time and dose. The cells showed morphologic changes of the early stage of apoptosis under the light microscope: the shrunk round cells, condensed cytoplasma and pycnosis of nucleus. Apoptotic cells and apoptotic body could be found under the transmission electronic microscope. The analysis of cell cycle indicated that oxaliplatin blocked cells at S and G2/M phases and the cells of G0/Gl phase reduced. When treated with oxaliplatin for 72h, the expressions of cyclin A and Bax were up-regulated, mutant type P53, Bcl-2 and Myc were down-regulated, and Fas was not changed. Conclusion: Oxaliplatin could inhibit the proliferation of the hepatoma cell lines. Cells were blocked at S and G2/M phases. The apoptosis was related to the up-regulation of Bax and down-regulation of mutant type P53, Bcl-2 and Myc. Oxaliplatin could not induce apoptosis through the Fas pathway.

  18. Serotonin regulates osteoblast proliferation and function in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Dai, S.Q.; Yu, L.P. [Department of Orthopedic Surgery, The First Affiliated Hospital, Nanjing Medical University, Nanjing, Jiangsu (China); Shi, X. [Department of Obstetrics and Gynecology, The First Affiliated Hospital, Nanjing Medical University, Nanjing, Jiangsu (China); Wu, H. [Emergency Department, The First Affiliated Hospital, Soochow University, Suzhou (China); Shao, P.; Yin, G.Y.; Wei, Y.Z. [Department of Orthopedic Surgery, The First Affiliated Hospital, Nanjing Medical University, Nanjing, Jiangsu (China)

    2014-08-01

    The monoamine serotonin (5-hydroxytryptamine, 5-HT), a well-known neurotransmitter, also has important functions outside the central nervous system. The objective of this study was to investigate the role of 5-HT in the proliferation, differentiation, and function of osteoblasts in vitro. We treated rat primary calvarial osteoblasts with various concentrations of 5-HT (1 nM to 10 µM) and assessed the rate of osteoblast proliferation, expression levels of osteoblast-specific proteins and genes, and the ability to form mineralized nodules. Next, we detected which 5-HT receptor subtypes were expressed in rat osteoblasts at different stages of osteoblast differentiation. We found that 5-HT could inhibit osteoblast proliferation, differentiation, and mineralization at low concentrations, but this inhibitory effect was mitigated at relatively high concentrations. Six of the 5-HT receptor subtypes (5-HT{sub 1A}, 5-HT{sub 1B}, 5-HT{sub 1D}, 5-HT{sub 2A}, 5-HT{sub 2B}, and 5-HT{sub 2C}) were found to exist in rat osteoblasts. Of these, 5-HT{sub 2A} and 5-HT{sub 1B} receptors had the highest expression levels, at both early and late stages of differentiation. Our results indicated that 5-HT can regulate osteoblast proliferation and function in vitro.

  19. Automating proliferation rate estimation from Ki-67 histology images

    Science.gov (United States)

    Al-Lahham, Heba Z.; Alomari, Raja S.; Hiary, Hazem; Chaudhary, Vipin

    2012-03-01

    Breast cancer is the second cause of women death and the most diagnosed female cancer in the US. Proliferation rate estimation (PRE) is one of the prognostic indicators that guide the treatment protocols and it is clinically performed from Ki-67 histopathology images. Automating PRE substantially increases the efficiency of the pathologists. Moreover, presenting a deterministic and reproducible proliferation rate value is crucial to reduce inter-observer variability. To that end, we propose a fully automated CAD system for PRE from the Ki-67 histopathology images. This CAD system is based on a model of three steps: image pre-processing, image clustering, and nuclei segmentation and counting that are finally followed by PRE. The first step is based on customized color modification and color-space transformation. Then, image pixels are clustered by K-Means depending on the features extracted from the images derived from the first step. Finally, nuclei are segmented and counted using global thresholding, mathematical morphology and connected component analysis. Our experimental results on fifty Ki-67-stained histopathology images show a significant agreement between our CAD's automated PRE and the gold standard's one, where the latter is an average between two observers' estimates. The Paired T-Test, for the automated and manual estimates, shows ρ = 0.86, 0.45, 0.8 for the brown nuclei count, blue nuclei count, and proliferation rate, respectively. Thus, our proposed CAD system is as reliable as the pathologist estimating the proliferation rate. Yet, its estimate is reproducible.

  20. Climate Change, Nuclear Power and Nuclear Proliferation: Magnitude Matters

    Energy Technology Data Exchange (ETDEWEB)

    Robert J. Goldston

    2010-03-03

    Integrated energy, environment and economics modeling suggests electrical energy use will increase from 2.4 TWe today to 12 TWe in 2100. It will be challenging to provide 40% of this electrical power from combustion with carbon sequestration, as it will be challenging to provide 30% from renewable energy sources. Thus nuclear power may be needed to provide ~30% by 2100. Calculations of the associated stocks and flows of uranium, plutonium and minor actinides indicate that the proliferation risks at mid-century, using current light-water reactor technology, are daunting. There are institutional arrangements that may be able to provide an acceptable level of risk mitigation, but they will be difficult to implement. If a transition is begun to fast-spectrum reactors at mid-century, without a dramatic change in the proliferation risks of such systems, at the end of the century proliferation risks are much greater, and more resistant to mitigation. The risks of nuclear power should be compared with the risks of the estimated 0.64oC long-term global surface-average temperature rise predicted if nuclear power were replaced with coal-fired power plants without carbon sequestration. Fusion energy, if developed, would provide a source of nuclear power with much lower proliferation risks than fission.