WorldWideScience

Sample records for cell colony formation

  1. Human T cell colony formation in microculture: analysis of growth requirements and functional activities.

    Science.gov (United States)

    Gelfand, E W; Lee, J W; Dosch, H M; Price, G B

    1981-03-01

    A microculture method in methylcellulose has been developed for the study of human T cell colony formation. The technique is simple, reliable, does not require preincubation with lectin and requires small numbers of cells. Colony formation was dependent on the presence of phytohemagglutin-conditioned medium, a T colony precursor cell (TCPC), and a "helper" or accessory T cell. Plating efficiency was increased 10-fold in the presence of irradiated feeder cells. Progenitors of the T colony cells were identified in peripheral blood, tonsil, and spleen but not in thymus or thoracic duct. They were isolated in the E-rosetting, theophylline-resistant, Fc-IgG-negative cell populations. In peripheral blood the frequency of TCPC and accessory cells, the T colony forming unit, was estimated to be 8 X 10(-3). Colony cells proliferated in response to lectins and allogeneic cells. Forty to 80% of the cells were Ia-positive and stimulated both autologous and allogeneic mixed lymphocyte responses. They were incapable of mediating antibody-dependent cytotoxicity. In contrast, they were effective in assays of spontaneous cytotoxicity but only against certain target cells. This method for the analysis of T colony formation should prove valuable in the functional analysis of T cell subsets in immunodeficiency states or the transplant recipient.

  2. Cell colony formation induced by Xenopus egg extract as a marker for improvement of cloned blastocyst formation in pig

    DEFF Research Database (Denmark)

    Liu, Ying; Østrup, Olga; Li, Juan

    2011-01-01

    method based on the colony formation of cells after extract treatment, and subsequent in vitro cloning efficiency using treated cells as chromatin donors. Porcine fetal fibroblasts were treated with each batch of extract, and cultured in embryonic stem cell (ES) medium for 12 days. The number of forming...

  3. Extrapulmonary colony formation after intravenous injection of tumour cells into heparin treated animals

    NARCIS (Netherlands)

    Maat, B.

    1978-01-01

    Recent data on extrapulmonary colony formation after heparin administration are inconclusive. A systemic study of this topic was undertaken with 4 experimental tumour systems and 2 distinct periods of reduced clotting capacity in rats and mice. I.v. injection of various numbers of tumour cells into

  4. Mouse B- and T-cell colony formation in vitro. I. Separation of colony-promoting and -inhibiting activities in concanavalin A rat spleen conditioned medium

    DEFF Research Database (Denmark)

    Claësson, M H; Nissen, Mogens Holst; Röpke, C

    1984-01-01

    Rat spleen cell cultures exposed for 24 h to concanavalin A (Con A-CM) contain, in addition to interleukin 2 (IL-2), factors that promote colony formation in vitro by mouse T cells (TCPA) and B cells (BCPA). TCPA and BCPA are separable on a Sephadex G-75 column. TCPA has a molecular weight of 15......,000 daltons and shows the same elution profile as IL-2. Absorption studies with Con A-activated T cells suggested that TCPA and IL-2 are the same entity. BCPA has an apparent molecular weight of 45,000 daltons and stimulates colony formation by B lymphocytes seeded at very low cell density (10(4) - 5 X 10......,000-130,000 and about 50,000, respectively. Because of the specificity, simplicity and sensitivity of B and T colony formation these assay systems should be valuable tools for in vitro testing of biological activities regulating the immune system....

  5. Mouse B- and T-cell colony formation in vitro. I. Separation of colony-promoting and -inhibiting activities in concanavalin A rat spleen conditioned medium

    DEFF Research Database (Denmark)

    Claësson, M H; Nissen, Mogens Holst; Röpke, C

    1984-01-01

    Rat spleen cell cultures exposed for 24 h to concanavalin A (Con A-CM) contain, in addition to interleukin 2 (IL-2), factors that promote colony formation in vitro by mouse T cells (TCPA) and B cells (BCPA). TCPA and BCPA are separable on a Sephadex G-75 column. TCPA has a molecular weight of 15...

  6. Hypoxia enhances proliferation through increase of colony formation rate with chondrogenic potential in primary synovial mesenchymal stem cells.

    Science.gov (United States)

    Ohara, Toshiyuki; Muneta, Takeshi; Nakagawa, Yusuke; Matsukura, Yu; Ichinose, Shizuko; Koga, Hideyuki; Tsuji, Kunikazu; Sekiya, Ichiro

    2016-01-01

    Synovial mesenchymal stem cells (MSCs) are an attractive cell source for cartilage and meniscus regeneration. Use of primary MSCs is the preferable because these cells are safer than cells passaged several times in terms of probability of chromosome abnormalities. The effect of hypoxia on the proliferation of MSCs is controversial and remains unknown in primary synovial MSCs. Primary synovial MSCs were cultured at normoxia or hypoxia, and colony number, cell number, surface epitopes, mitochondria activity, TEM finding, and chondrogenic potential were analyzed. To investigate the effect of hypoxia on attachment of synovial MSCs, cells were cultured at hypoxia for the first 3 days, then cultured at normoxia. To investigate the effect of hypoxia on proliferation, cells were also cultured at hypoxia for the last 11 days. Hypoxia increased colony number and cell number per dish in primary synovial MSCs. Hypoxia did not affect cell number per colony, surface epitopes, mitochondria activity, TEM finding or chondrogenic potential. Hypoxia for the first 3 days did not alter colony number per dish or cell number per dish, while hypoxia for the last 11 days increased. Hypoxia enhanced proliferation through increase of colony formation rate with chondrogenic potential in primary synovial MSCs.

  7. Enhancement of committed hematopoietic stem cell colony formation by nandrolone decanoate after sublethal whole body irradiation

    International Nuclear Information System (INIS)

    Gallicchio, V.S.; Chen, M.G.; Watts, T.D.

    1984-01-01

    The ability of an anabolic steroid, nandrolone decanoate, to increase committed topoietic stem cell (CFU-gm, CFU-e, and BFU-e) colony formation after sublethal irradiation was evaluated. Immediately after receiving whole body irradiation and on the next two days, each mouse was injected intraperitoneally with nandrolone decanoate (1.25 mg) in propylene glycol. Irradiated control mice received only propylene glycol. Compared to controls, drug-treated mice showed marked peripheral blood leukocytosis and more stable packed red cell volume. Drug-treated mice also demonstrated increased erythropoiesis, as CFU-e/BFU-e concentrations from both marrow (9% to 581%) and spleen (15% to 797%) were elevated. Granulopoiesis was increased similarly, as CFU-gm concentrations from marrow (38% to 685%) and spleen (9% to 373%) were elevated. These results demonstrate that nandrolone decanoate enhances hematopoietic stem cell recovery after sublethal whole body irradiation. This suggests that following hematopoietic suppression, nandrolone decanoate may stimulate the recovery of hematopoiesis at the stem cell level and in peripheral blood

  8. Enhancement of committed hematopoietic stem cell colony formation by nandrolone decanoate after sublethal whole body irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Gallicchio, V.S.; Chen, M.G.; Watts, T.D.

    1984-11-01

    The ability of an anabolic steroid, nandrolone decanoate, to increase committed topoietic stem cell (CFU-gm, CFU-e, and BFU-e) colony formation after sublethal irradiation was evaluated. Immediately after receiving whole body irradiation and on the next two days, each mouse was injected intraperitoneally with nandrolone decanoate (1.25 mg) in propylene glycol. Irradiated control mice received only propylene glycol. Compared to controls, drug-treated mice showed marked peripheral blood leukocytosis and more stable packed red cell volume. Drug-treated mice also demonstrated increased erythropoiesis, as CFU-e/BFU-e concentrations from both marrow (9% to 581%) and spleen (15% to 797%) were elevated. Granulopoiesis was increased similarly, as CFU-gm concentrations from marrow (38% to 685%) and spleen (9% to 373%) were elevated. These results demonstrate that nandrolone decanoate enhances hematopoietic stem cell recovery after sublethal whole body irradiation. This suggests that following hematopoietic suppression, nandrolone decanoate may stimulate the recovery of hematopoiesis at the stem cell level and in peripheral blood.

  9. Abiotic factors in colony formation: effects of nutrition and light on extracellular polysaccharide production and cell aggregates of Microcystis aeruginosa

    Science.gov (United States)

    Yang, Zhen; Kong, Fanxiang

    2013-07-01

    Colony morphology is important for Microcystis to sustain a competitive advantage in eutrophic lakes. The mechanism of colony formation in Microcystis is currently unclear. Extracellular polysaccharide (EPS) has been reported to play an important role in cell aggregate formation of some phytoplankton. Microcystis aeruginosa was cultivated under varied abiotic conditions, including different nutrient, light, and temperature conditions, to investigate their effects on EPS production and morphological change. The results show that nutrient concentration and light intensity have great effects on EPS productionin M. aeruginosa. There was a considerable increase in EPS production after M. aeruginosa was cultivated in adjusted culture conditions similar to those present in the field (28.9 mg C/L, 1.98 mg N/L, 0.65 mg P/L, light intensity: 100 μmol/(m2 · s)). These results indicate that abiotic factors might be one of the triggers for colony formation in Microcystis.

  10. Convergence of bone morphogenetic protein and laminin-1 signaling pathways promotes proliferation and colony formation by fetal mouse pancreatic cells

    International Nuclear Information System (INIS)

    Jiang Fangxu; Harrison, Leonard C.

    2005-01-01

    We previously reported that bone morphogenetic proteins (BMPs), members of the transforming growth factor superfamily, together with the basement membrane glycoprotein laminin-1 (Ln-1), promote proliferation of fetal pancreatic cells and formation of colonies containing peripheral insulin-positive cells. Here, we further investigate the cross-talk between BMP and Ln-1 signals. By RT-PCR, receptors for BMP (BMPR) (excepting BMPR-1B) and Ln-1 were expressed in the fetal pancreas between E13.5 and E17.5. Specific blocking antibodies to BMP-4 and -6 and selective BMP antagonists partially inhibited colony formation by fetal pancreas cells. Colony formation induced by BMP-6 and Ln-1 was completely abolished in a dose-dependent manner by blocking Ln-1 binding to its α 6 integrin and α-dystroglycan receptors or by blocking the Ln-1 signaling molecules, phosphatidyl-inositol-3-kinase (P13K) and MAP kinase kinase-1. These results demonstrate a convergence of BMP and Ln-1 signaling through P13K and MAP kinase pathways to induce proliferation and colony formation in E15.5 fetal mouse pancreatic cells

  11. Colony formation in the cyanobacterium Microcystis.

    Science.gov (United States)

    Xiao, Man; Li, Ming; Reynolds, Colin S

    2018-02-22

    Morphological evolution from a unicellular to multicellular state provides greater opportunities for organisms to attain larger and more complex living forms. As the most common freshwater cyanobacterial genus, Microcystis is a unicellular microorganism, with high phenotypic plasticity, which forms colonies and blooms in lakes and reservoirs worldwide. We conducted a systematic review of field studies from the 1990s to 2017 where Microcystis was dominant. Microcystis was detected as the dominant genus in waterbodies from temperate to subtropical and tropical zones. Unicellular Microcystis spp. can be induced to form colonies by adjusting biotic and abiotic factors in laboratory. Colony formation by cell division has been induced by zooplankton filtrate, high Pb 2+ concentration, the presence of another cyanobacterium (Cylindrospermopsis raciborskii), heterotrophic bacteria, and by low temperature and light intensity. Colony formation by cell adhesion can be induced by zooplankton grazing, high Ca 2+ concentration, and microcystins. We hypothesise that single cells of all Microcystis morphospecies initially form colonies with a similar morphology to those found in the early spring. These colonies gradually change their morphology to that of M. ichthyoblabe, M. wesenbergii and M. aeruginosa with changing environmental conditions. Colony formation provides Microcystis with many ecological advantages, including adaption to varying light, sustained growth under poor nutrient supply, protection from chemical stressors and protection from grazing. These benefits represent passive tactics responding to environmental stress. Microcystis colonies form at the cost of decreased specific growth rates compared with a unicellular habit. Large colony size allows Microcystis to attain rapid floating velocities (maximum recorded for a single colony, ∼ 10.08 m h -1 ) that enable them to develop and maintain a large biomass near the surface of eutrophic lakes, where they may shade

  12. Comparison of the colony formation and crystal violet cell proliferation assays to determine cellular radiosensitivity in a repair-deficient MCF10A cell line

    Energy Technology Data Exchange (ETDEWEB)

    Vandersickel, Veerle [Department of Basic Medical Sciences, Ghent University, Campus Heymans, De Pintelaan 185 (6B3), 9000 Gent (Belgium); Slabbert, Jacobus [NRF iThemba LABS (Laboratory for Accelerated Based Sciences), PO box 722, 7129 Somerset West (South Africa); Thierens, Hubert [Department of Basic Medical Sciences, Ghent University, Campus Heymans, De Pintelaan 185 (6B3), 9000 Gent (Belgium); Vral, Anne, E-mail: anne.Vral@UGent.b [Department of Basic Medical Sciences, Ghent University, Campus Heymans, De Pintelaan 185 (6B3), 9000 Gent (Belgium)

    2011-01-15

    Colony formation as measured by the in vitro clonogenic assay is a very important endpoint to determine cellular radiosensitivity and tumor response to radiotherapy. In the framework of assessing in vitro cellular radiosensitivity, proliferation assays could represent an attractive alternative to the clonogenic assay for cell lines that do not form proper colonies. In the present study, we compared cellular radiosensitivity measurements obtained by the crystal violet (CV) cell proliferation assay and the standard colony formation assay in repair-deficient and-proficient human MCF10A cell lines. Compared to the clonogenic assay, the CV cell proliferation assay yielded higher surviving fractions for the same radiation dose. This is reflected in larger mean inactivation dose values - a parameter that reflects the area under the survival curve. However, as the dose modifying factors obtained by both assays are comparable, the CV cell proliferation assay can be used to compare the in vitro cellular radiosensitivity of cell lines that lack the ability to form well-defined colonies.

  13. Effect of fluid motion on colony formation in Microcystis aeruginosa

    Directory of Open Access Journals (Sweden)

    Lin Li

    2013-01-01

    Full Text Available Microcystis aeruginosa, generally occurring in large colonies under natural conditions, mainly exists as single cells in laboratory cultures. The mechanisms involved in colony formation in Microcystis aeruginosa and their roles in algal blooms remain unknown. In this study, based on previous research findings that fluid motion may stimulate the colony formation in green algae, culture experiments were conducted under axenic conditions in a circular water chamber where the flow rate, temperature, light, and nutrients were controlled. The number of cells of Microcystis aeruginosa, the number of cells per colony, and the colonial characteristics in various growth phases were observed and measured. The results indicated that the colony formation in Microcystis aeruginosa, which was not observed under stagnant conditions, was evident when there was fluid motion, with the number of cells per largest colony reaching 120 and the proportion of the number of cells in colonial form to the total number of cells and the mean number of cells per colony reaching their peak values at a flow rate of 35 cm/s. Based on the analysis of colony formation process, fluid motion stimulates the colony formation in Microcystis aeruginosa in the lag growth phase, while flushes and disaggregates the colonies in the exponential growth phase. The stimulation effect in the lag growth phase may be attributable to the involvement of fluid motion in a series of physiological processes, including the uptake of trace elements and the synthesis and secretion of polysaccharides. In addition, the experimental groups exhibiting typical colonial characteristics in the lag growth phase were found to have higher cell biomass in the later phase.

  14. Colony formation in agar: in vitro assay for haemopoietic stem cells

    NARCIS (Netherlands)

    Dicke, K.A.; Platenburg, M.G.C.; Bekkum, D.W. van

    1971-01-01

    Using a method in which embryo fibroblasts were used as feeder layers, the colony forming capacity in agar of a variety of mouse haemopoietic suspensions was compared with their CFUs content. A striking parallelism between the results of the two assays was found. In addition, under certain

  15. miR-21 inhibitor suppresses cell proliferation and colony formation through regulating the PTEN/AKT pathway and improves paclitaxel sensitivity in cervical cancer cells.

    Science.gov (United States)

    Du, Guohui; Cao, Dongmei; Meng, Lingzheng

    2017-05-01

    The present study aimed to investigate the role and the molecular mechanisms underlying the effects of microRNA-21 (miR-21) on the proliferation, apoptosis and colony formation of cervical cancer cells, and to examine the role of miR-21 in mediating the sensitivity of cervical cancer cells to paclitaxel (PTX). Reverse transcription‑quantitative polymerase chain reaction was employed to determine the level of miR‑21 in various cervical cancer and normal cervical cells. The results revealed that the expression levels of miR-21 in cervical cancer cells were markedly higher when compared with normal cervical cells. Subsequently, a miR‑21 inhibitor or negative control (NC) was transfected into cervical cancer cells. Cell viability, colony formation and apoptosis were then analyzed using an MTT assay, crystal violet and Annexin V-fluorescein isothiocyanate/propidium iodide staining, respectively. The protein expression level of B-cell lymphoma‑2 (Bcl‑2), Bcl‑2‑associated X (Bax), programmed cell death 4 (PDCD4), survivin, c‑myc, phosphatase and tensin homolog (PTEN) and phosphorylated (p)‑AKT were determined by western blot analysis. The sensitivity of cervical cancer cells to PTX (25, 50 and 100 µg/ml) was characterized using an MTT assay. The results demonstrated that the miR-21 inhibitor promoted apoptosis of cervical cancer cells and suppressed their proliferation and colony formation when compared with the NC. In addition, the expression levels of Bcl‑2, survivin, c‑myc and p‑AKT were significantly downregulated in cells transfected with the miR‑21 inhibitor, whilst the expression levels of Bax, PDCD4 and PTEN were significantly upregulated. Furthermore, the miR‑21 inhibitor significantly enhanced the inhibition efficacy of PTX at a range of concentrations in cervical cancer cells. It was concluded that inhibition of miR‑21 suppressed cell proliferation and colony formation through regulating the PTEN/AKT pathway, and improved PTX

  16. Single cell time-lapse analysis reveals that podoplanin enhances cell survival and colony formation capacity of squamous cell carcinoma cells.

    Science.gov (United States)

    Miyashita, Tomoyuki; Higuchi, Youichi; Kojima, Motohiro; Ochiai, Atsushi; Ishii, Genichiro

    2017-01-06

    Tumor initiating cells (TICs) are characterized by high clonal expansion capacity. We previously reported that podoplanin is a TIC-specific marker for the human squamous cell carcinoma cell line A431. The aim of this study is to explore the molecular mechanism underlying the high clonal expansion potential of podoplanin-positive A431cells using Fucci imaging. Single podoplanin-positive cells created large colonies at a significantly higher frequency than single podoplanin-negative cells, whereas no difference was observed between the two types of cells with respect to cell cycle status. Conversely, the cell death ratio of progenies derived from podoplanin-positive single cell was significantly lower than that of cells derived from podoplanin-negative cells. Single A431 cells, whose podoplanin expression was suppressed by RNA interference, exhibited increased cell death ratios and decreased frequency of large colony forming. Moreover, the frequency of large colony forming decreased significantly when podoplanin-positive single cells was treated with a ROCK (Rho-associated coiled-coil kinase) inhibitor, whereas no difference was observed in single podoplanin-negative cells. Our current study cleared that high clonal expansion capacity of podoplanin-positive TICs populations was the result of reduced cell death by podoplanin-mediated signaling. Therefore, podoplanin activity may be a therapeutic target in the treatment of squamous cell carcinomas.

  17. Synergism between erythropoietin and interleukin-3 in the induction of hematopoietic stem cell proliferation and erythroid burst colony formation

    NARCIS (Netherlands)

    Migliaccio, G.; Migliaccio, A.R.; Visser, J.W.M

    1988-01-01

    The influence of recombinant erythropoietin (Ep) and interleukin-3 (IL-3) on the proliferation and differentiation of murine hematopoietic stem and progenitor cells was investigated in serum-deprived cultures. The differentiation of progenitor cells, purified by collecting blast cell colonies from

  18. Antisense oligonucleotide mediated knockdown of HOXC13 affects cell growth and induces apoptosis in tumor cells and over expression of HOXC13 induces 3D-colony formation.

    Science.gov (United States)

    Kasiri, Sahba; Ansari, Khairul I; Hussain, Imran; Bhan, Arunoday; Mandal, Subhrangsu S

    2013-01-01

    HOXC13 is a homeobox containing gene that plays crucial roles in hair development and origin of replication. Herein, we investigated the biochemical functions of HOXC13 and explored its potential roles in tumor cell viability. We have designed a phosphorothioate based antisense-oligonucleotide that specifically knockdown HOXC13 in cultured cells. Cell viability and cytotoxicity assays demonstrated that HOXC13 is essential for cell growth and viability. Antisense-mediated knockdown of HOXC13 affected the cell viability and induced apoptosis in cultured tumor cells. HOXC13 regulates the expression of cyclins and antisense-mediated knockdown of HOXC13 resulted in cell cycle arrest and apoptosis in colon cancer cells. Finally over expression of HOXC13 resulted in 3D-colony formation in soft-agar assay indicating its potential roles in cell proliferation and tumorigenesis.

  19. Thymidine kinase deficient human cells have increased UV sensitivity in their capacity to support herpes simplex virus but normal UV sensitivity for colony formation

    International Nuclear Information System (INIS)

    Rainbow, A.J.

    1989-01-01

    A thymidine kinase deficient (tk - ) and two thymidine kinase proficient (tk + ) human cell lines were compared for UV sensitivity using colony-forming ability as well as their capacity to support the plaque formation of herpes simplex type 1 (HSV-1).The tk - line (143 cells) was a derivative of one of the tk + lines (R970-5), whereas the other tk + line (AC4 cells) was a derivative of the 143 cells obtained by transfection with purified sheared HSV-2 DNA encoding the viral tk gene. 143, R970-5 and AC4 cells showed a similar UV sensitivity for colony-forming ability. In contrast, the capacity to support HSV-1 plaque formation immediately (within 1 h) afte UV-irradiation was reduced to a greater extent in the 143 cells compared to the R970-5 and AC4 cells. Capacity curves for plaque formation of the HSV-1: KOS wild-type (tk + ) strain were similar to those for the HSV-1: PTK3B mutant (tk - ) strain were similar to those for the HSV-1: PTK3B mutant (tk - ) strain in the 3 cell strains, indicating that the viral tk gene does not influence the ability of HSV-1 to form plaques in UV-irradiated compared to unirradiated human cells. Cellular capacity for HSV-1 plaque formation was found to recover in both tk - and tk + cells for cultures infected 24 h after UV-irradiation. These results suggest that repair of UV-damaged DNA takes place to a similar extent in both tk - and tk + human cells, but the kinetics of repair are initially slower in tk - compared to tk + human cells. (author). 33 refs.; 3 figs.; 1 tab

  20. Effects of Melophlins on Colony Formation of Chinese Hamster V79 Cells and IL-8 Production in PMA-stimulated HL-60 Cells

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    Michio Namikoshi

    2007-01-01

    Full Text Available We have recently isolated four new melophlins P (1, Q (2, R (3, and S (4 together with seven known melophlins A (5, D (6, E (7, G (8, H (9, I (10, and O (11 from two marine sponges of the genus Melophlus collected in Palau. In this study, the influence of these compounds on the colony formation of Chinese hamster V79 cells and the production of IL-8 in PMA-stimulated HL-60 cells were examined. These 11 compounds did not show any effect on IL-8 production. The EC50 values of compounds 2, 3, 4, 5, 7, 9, 10, and 11 against V79 cells were 44.0, 13.3, 16.7, 27.2, 19.8, 8.5, 23.1, and 9.6 μM, respectively. The linear-chain-type compounds (1, 6, and 8 were not active against V79 cells at 50 μM. Although the growth inhibitory activity of these melophlins was not remarkable, some structure-activity relationships of these compounds against V79 and murine leukemia L1210 cells were observed.

  1. Radial and spiral stream formation in Proteus mirabilis colonies.

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    Chuan Xue

    2011-12-01

    Full Text Available The enteric bacterium Proteus mirabilis, which is a pathogen that forms biofilms in vivo, can swarm over hard surfaces and form a variety of spatial patterns in colonies. Colony formation involves two distinct cell types: swarmer cells that dominate near the surface and the leading edge, and swimmer cells that prefer a less viscous medium, but the mechanisms underlying pattern formation are not understood. New experimental investigations reported here show that swimmer cells in the center of the colony stream inward toward the inoculation site and in the process form many complex patterns, including radial and spiral streams, in addition to previously-reported concentric rings. These new observations suggest that swimmers are motile and that indirect interactions between them are essential in the pattern formation. To explain these observations we develop a hybrid model comprising cell-based and continuum components that incorporates a chemotactic response of swimmers to a chemical they produce. The model predicts that formation of radial streams can be explained as the modulation of the local attractant concentration by the cells, and that the chirality of the spiral streams results from a swimming bias of the cells near the surface of the substrate. The spatial patterns generated from the model are in qualitative agreement with the experimental observations.

  2. Targeting DTL induces cell cycle arrest and senescence and suppresses cell growth and colony formation through TPX2 inhibition in human hepatocellular carcinoma cells.

    Science.gov (United States)

    Chen, Yu-Chia; Chen, I-Shu; Huang, Guan-Jin; Kang, Chi-Hsiang; Wang, Kuo-Chiang; Tsao, Min-Jen; Pan, Hung-Wei

    2018-01-01

    Hepatocellular carcinoma (HCC) has an increasing incidence and high mortality. Surgical operation is not a comprehensive strategy for liver cancer. Moreover, tolerating systemic chemotherapy is difficult for patients with HCC because hepatic function is often impaired due to underlying cirrhosis. Therefore, a comprehensive strategy for cancer treatment should be developed. DTL (Cdc10-dependent transcript 2) is a critical regulator of cell cycle progression and genomic stability. In our previous study, the upregulation of DTL expression in aggressive HCC correlated positively with tumor grade and poor patient survival. We hypothesize that targeting DTL may provide a novel therapeutic strategy for liver cancer. DTL small interference RNAs were used to knock down DTL protein expression. A clonogenic assay, immunostaining, double thymidine block, imaging flow cytometry analysis, and a tumor spheroid formation assay were used to analyze the role of DTL in tumor cell growth, cell cycle progression, micronucleation, ploidy, and tumorigenicity. Our results demonstrated that targeting DTL reduced cell cycle regulators and chromosome segregation genes, resulting in increased cell micronucleation. DTL depletion inhibited liver cancer cell growth, increased senescence, and reduced tumorigenesis. DTL depletion resulted in the disruption of the mitotic proteins cyclin B, CDK1, securin, seprase, Aurora A, and Aurora B as well as the upregulation of the cell cycle arrest gene p21 . A rescue assay indicated that DTL should be targeted through TPX2 downregulation for cancer cell growth inhibition. Moreover, DTL silencing inhibited the growth of patient-derived primary cultured HCC cells. Our study results indicate that DTL is a potential novel target gene for treating liver cancer through liver cancer cell senescence induction. Furthermore, our results provide insights into molecular mechanisms for targeting DTL in liver cancer cells. The results also indicate several other starting

  3. Automated counting of mammalian cell colonies.

    Science.gov (United States)

    Barber, P R; Vojnovic, B; Kelly, J; Mayes, C R; Boulton, P; Woodcock, M; Joiner, M C

    2001-01-01

    Investigating the effect of low-dose radiation exposure on cells using assays of colony-forming ability requires large cell samples to maintain statistical accuracy. Manually counting the resulting colonies is a laborious task in which consistent objectivity is hard to achieve. This is true especially with some mammalian cell lines which form poorly defined or 'fuzzy' colonies, typified by glioma or fibroblast cell lines. A computer-vision-based automated colony counter is presented in this paper. It utilizes novel imaging and image-processing methods involving a modified form of the Hough transform. The automated counter is able to identify less-discrete cell colonies typical of these cell lines. The results of automated colony counting are compared with those from four manual (human) colony counts for the cell lines HT29, A172, U118 and IN1265. The results from the automated counts fall well within the distribution of the manual counts for all four cell lines with respect to surviving fraction (SF) versus dose curves, SF values at 2 Gy (SF2) and total area under the SF curve (Dbar). From the variation in the counts, it is shown that the automated counts are generally more consistent than the manual counts.

  4. Intermittent feeding as a factor enhancing hemopoietic stem cell proliferation and spleen colony formation in irradiated mice

    International Nuclear Information System (INIS)

    Kozubik, A.; Pospisil, M.

    1985-01-01

    The influence of metabolic stimulation induced by a 3 weeks' adaption of the animals to intermittent food intake on hemopoietic stem cells was investigated in mice. The methods used included transplantation of bone marrow to lethally irradiated recipients, assay of CFUs number, seeding efficiency, and incorporation of 125 iodode oxyuridine into the DNA of spleen cells. A stimulatory effect of the metabolically influenced hemopoietic environment on the proliferative activity in stem cell compartments and on the recovery of hemopoietic organs was demonstrated. These stimulatory effects were most marked when the bone marrow of metabolically influenced donors was transplanted to similarly influenced recipients. (orig.)

  5. Granulocyte macrophage colony-stimulating factor enhances the modulatory effect of cytokines on monocyte-derived multinucleated giant cell formation and fungicidal activity against Paracoccidioides brasiliensis

    Directory of Open Access Journals (Sweden)

    Magda Paula Pereira do Nascimento

    2011-09-01

    Full Text Available Multinucleated giant cells (MGC are cells present in characteristic granulomatous inflammation induced by intracellular infectious agents or foreign materials. The present study evaluated the modulatory effect of granulocyte macrophage colony-stimulating factor (GM-CSF in association with other cytokines such as interferon-gamma (IFN-γ, tumour necrosis factor-alpha, interleukin (IL-10 or transforming growth factor beta (TGF-β1 on the formation of MGC from human peripheral blood monocytes stimulated with Paracoccidioides brasiliensis antigen (PbAg. The generation of MGC was determined by fusion index (FI and the fungicidal activity of these cells was evaluated after 4 h of MGC co-cultured with viable yeast cells of P. brasiliensis strain 18 (Pb18. The results showed that monocytes incubated with PbAg and GM-CSF plus IFN-γ had a significantly higher FI than in all the other cultures, while the addition of IL-10 or TGF-β1 had a suppressive effect on MGC generation. Monocytes incubated with both pro and anti-inflammatory cytokines had a higher induction of foreign body-type MGC rather than Langhans-type MGC. MGC stimulated with PbAg and GM-CSF in association with the other cytokines had increased fungicidal activity and the presence of GM-CSF also partially inhibited the suppressive effects of IL-10 and TGF-β1. Together, these results suggest that GM-CSF is a positive modulator of PbAg-stimulated MGC generation and on the fungicidal activity against Pb18.

  6. Enhancement of erythroid colony formation in vitro by spleen extract from irradiated rats

    International Nuclear Information System (INIS)

    Kasai, Shiro; Terasawa, Waka; Kodama, Hiroaki; Terasawa, Takashi

    1980-01-01

    The effect of spleen extract from irradiated rats on CFU-e and BFU-e colony formation of rat bone marrow cells was investigated by using modified plasma clot culture media. In the presence of erythropoietin (Ep), CFU-e colony formation peaked at 48 hr of culture, and the Ep-induced increase of CFU-e colonies was dose-dependent. The addition of spleen extract enhanced the colony formation more than two-fold in the Ep-containing culture. BFU-e colony formation was also enhanced by the addition of spleen extract. These results indicate that spleen extract from irradiated rats contains factor(s) which stimulates the proliferation of erythroid progenitors. (author)

  7. Ammonia Signaling in Yeast Colony Formation

    Czech Academy of Sciences Publication Activity Database

    Palková, Z.; Váchová, Libuše

    2003-01-01

    Roč. 225, - (2003), s. 229-272 ISSN 0074-7696 R&D Projects: GA ČR GA204/02/0650 Grant - others:GA of Charles University(CZ) 141/2001/B-BIO/PrF and EMBO YIP for ZP Institutional research plan: CEZ:MSM 113100003 Keywords : yeast colonies * ammonia * ammonium Subject RIV: EE - Microbiology, Virology Impact factor: 4.286, year: 2003

  8. 17β-Estradiol regulates cell proliferation, colony formation, migration, invasion and promotes apoptosis by upregulating miR-9 and thus degrades MALAT-1 in osteosarcoma cell MG-63 in an estrogen receptor-independent manner

    Energy Technology Data Exchange (ETDEWEB)

    Fang, Dengfeng; Yang, Hui; Lin, Jing; Teng, Yi; Jiang, Yingying; Chen, Jiao; Li, Yu, E-mail: yuli_scu@163.com

    2015-02-20

    In bone, different concentration of estrogen leads to various of physiological processes in osteoblast, such as the proliferation, migration, and apoptosis in an estrogen receptor-dependent manner. But little was known about the estrogen effects on osteosarcoma (OS). In this study, OS cell MG-63 was treated with low (1 nM) or high (100 nM) dose of 17β-Estradiol (E2) with the presence or absence of estrogen receptor α (ERα), for evaluating the E2 effects on proliferation, migration, invasion, colony formation and apoptosis. Consistent with a previous study, high dose of E2 treatment dramatically downregulated expressing level of long non-coding RNA metastasis associated lung adenocarcinoma transcript 1 (MALAT-1). The observation of upregulation of miR-9 after a high dose of E2 treatment indicated the cause of MALAT-1 reduction. Downregulation of MALAT-1 promoted the combination of SFPQ/PTBP2 complex. It was also observed that the proliferation, migration, invasion, colony formation and apoptosis of OS cells were remarkably affected by high dose of E2 treatment, but not by low dose, in an ERα independent manner. Furthermore, the abolishment of the effects on these physiological processes caused by ectopic expression of miR-9 ASOs suggested the necessity of miR-9 in MALAT-1 regulation. Here we found that the high dose of E2 treatment upregulated miR-9 thus posttranscriptionally regulated MALAT-1 RNA level in OS cells, and then the downregulation of MALAT-1 inhibited cell proliferation, migration, invasion and epithelial–mesenchymal transition (EMT) processes in the E2-dose dependent and ER-independent ways. - Highlights: • E2 affects osteosarcoma cell MG-63 in an Estrogen receptor-independent way. • High dose of E2 treatment upregulates miR-9 which target to MALAT-1 RNA. • Upregulated miR-9 degrades MALAT-1 and thus affects combination of SFPQ/PTBP2. • E2 treatment block cell proliferation, colony formation, mobility, and enhance apoptosis.

  9. Mixed colony formation in vitro by the heterogeneous compartment of multipotential progenitors in human bone marrow.

    Science.gov (United States)

    Holyoake, T L; Freshney, M G; Konwalinka, G; Haun, M; Petzer, A; Fitzsimons, E; Lucie, N P; Wright, E G; Pragnell, I B

    1993-02-01

    The physiology of the human haemopoietic primitive progenitor populations can be studied in normal and disease states by clonal in vitro cultures in which the primitive progenitor cells proliferate and differentiate to form mixed colonies. For many applications it is essential that such assays detect a high proportion of primitive progenitor cells. We describe an in vitro assay which detects a high incidence of human CD34+ multipotential progenitor cells. Bone marrow mononuclear cells (MNC) or selected CD34+ cells were plated at low cell concentrations in semisolid agar cultures with synergizing growth factor combinations. The optimum growth factor combination of conditioned medium from Mia PaCa-2 cells (Mia-CM), recombinant granulocyte-macrophage colony-stimulating factor and recombinant stem cell factor (SCF) supported the formation of macroscopic (> or = mm) colonies (97% of which were multilineage), at an average incidence of 250/10(5) MNC. The colony-forming cells (human colony-forming unit, type A) detected, showed a low cycling status (7.3%) and the macroscopic colonies had a high replating efficiency (46%), reflecting their probable primitive nature. This assay should prove invaluable, for studies on the regulation of proliferation of the multipotential compartment and in studies involving the assessment of these cells in transplantation and neoplastic disease.

  10. Downregulation of ROS-FIG inhibits cell proliferation, colony-formation, cell cycle progression, migration and invasion, while inducing apoptosis in intrahepatic cholangiocarcinoma cells

    OpenAIRE

    DENG, GANG; HU, CHENGHUAN; ZHU, LEI; HUANG, FEIZHOU; HUANG, WEI; XU, HONGBO; NIE, WANPIN

    2014-01-01

    Intrahepatic cholangiocarcinoma (ICC) is the second most common primary liver cancer with poor responsiveness to existing drug therapies. Therefore, novel treatment strategies against ICC are required to improve survival. The aim of this study was to demonstrate the role of fused-in-glioblastoma-c-ros-oncogene1 (FIG-ROS) fusion gene in ICC. ROS was positively expressed in ICC tissues and HUCCT1 cells. Plasmids expressing ROS- and FIG-specific shRNAs were constructed and transfected into HUCCT...

  11. Saccharomyces cerevisiae IRR1 protein is indirectly involved in colony formation.

    Science.gov (United States)

    Kurlandzka, A; Rytka, J; Rózalska, B; Wysocka, M

    1999-01-15

    The ability of a microorganism to adhere to a solid support and to initiate a colony is often the first stage of microbial infections. To date, studies on S. cerevisiae cell-cell and cell-solid support interactions concerned only cell agglutination during mating and flocculation. Colony formation has not been studied before probably because this species is not pathogenic. However, S. cerevisiae can be a convenient model to study this process, thanks to well-developed genetics and the full knowledge of its nucleotide sequence. A preliminary characterization of the recently cloned essential IRR1 gene indicated that it may participate in cell-cell/substrate interactions. Here we show that lowering the level of expression of IRR1 (after fusion with a regulatory catalase A gene promoter) affects colony formation and disturbs zygote formation and spore germination. All these processes involve cell-cell or cell-solid support contacts. The IRR1 protein is localized in the cytosol as verified by immunofluorescence microscopy, and confirmed by cell fractionation and Western blotting. This indicates that Irr1p is not directly involved in the cell-solid support adhesion, but may be an element of a communication pathway between the cell and its surroundings.

  12. Antisense oligonucleotide mediated knockdown of HOXC13 affects cell growth and induces apoptosis in tumor cells and over expression of HOXC13 induces 3D-colony formation

    OpenAIRE

    Kasiri, Sahba; Ansari, Khairul I.; Hussain, Imran; Bhan, Arunoday; Mandal, Subhrangsu S.

    2012-01-01

    HOXC13 is a homeobox containing gene that plays crucial roles in hair development and origin of replication. Herein, we investigated the biochemical functions of HOXC13 and explored its potential roles in tumor cell viability. We have designed a phosphorothioate based antisense-oligonucleotide that specifically knockdown HOXC13 in cultured cells. Cell viability and cytotoxicity assays demonstrated that HOXC13 is essential for cell growth and viability. Antisense-mediated knockdown of HOXC13 a...

  13. Increased numbers of spleen colony forming units in B cell deficient CBA/N mice

    International Nuclear Information System (INIS)

    Wiktor-Jedrzejczak, W.; Krupienicz, A.; Scher, I.

    1986-01-01

    The formation of exogenous and endogenous spleen colonies was studied in immune-defective mice expressing the CBA/N X-linked xid gene. Bone marrow and spleen cells of immune deficient mice formed increased numbers of eight-day exogenous spleen colonies when transferred to either normal or B cell deficient lethally irradiated recipients. Moreover, defective mice showed increased formation of five-day endogenous spleen colonies (derived from transient endogenous colony forming units; T-CFU) and of ten-day endogenous spleen colonies (derived from CFU-S). Among the possible mechanisms responsible for the observed effects, the most probable appears the one in which decreased numbers of B cell precursors stimulate stem cell pools through a feedback mechanism. (orig.) [de

  14. Sequestration and Distribution Characteristics of Cd(II by Microcystis aeruginosa and Its Role in Colony Formation

    Directory of Open Access Journals (Sweden)

    Xiangdong Bi

    2016-01-01

    Full Text Available To investigate the sequestration and distribution characteristics of Cd(II by Microcystis aeruginosa and its role in Microcystis colony formation, M. aeruginosa was exposed to six different Cd(II concentrations for 10 days. Cd(II exposure caused hormesis in the growth of M. aeruginosa. Low concentrations of Cd(II significantly induced formation of small Microcystis colonies (P93% of Cd(II was sequestrated in the groups with lower added concentrations of Cd(II. More than 80% of the sequestrated Cd(II was bioadsorbed by bEPS. The Pearson correlation coefficients of exterior and interior factors related to colony formation of M. aeruginosa revealed that Cd(II could stimulate the production of IPS and bEPS via increasing Cd(II bioaccumulation and bioadsorption. Increased levels of cross-linking between Cd(II and bEPS stimulated algal cell aggregation, which eventually promoted the formation of Microcystis colonies.

  15. Characterization of the integrated filamentous phage Pf5 and its involvement in small-colony formation

    OpenAIRE

    Mooij, Marlies J.; Drenkard, Eliana; Llamas, Mar?a A.; Vandenbroucke-Grauls, Christina M. J. E.; Savelkoul, Paul H. M.; Ausubel, Frederick M.; Bitter, Wilbert

    2007-01-01

    Bacteriophages play an important role in bacterial virulence and phenotypic variation. It has been shown that filamentous bacteriophage Pf4 of Pseudomonas aeruginosa strain PAO1 mediates the formation of small-colony variants (SCVs) in biofilms. This morphology type is associated with parameters of poor lung function in cystic fibrosis patients, and SCVs are often more resistant to antibiotics than wild-type cells. P. aeruginosa strain PA14 also contains a Pf1-like filamentous prophage, which...

  16. Morphodynamics of a growing microbial colony driven by cell death

    Science.gov (United States)

    Ghosh, Pushpita; Levine, Herbert

    2017-11-01

    Bacterial cells can often self-organize into multicellular structures with complex spatiotemporal morphology. In this work, we study the spatiotemporal dynamics of a growing microbial colony in the presence of cell death. We present an individual-based model of nonmotile bacterial cells which grow and proliferate by consuming diffusing nutrients on a semisolid two-dimensional surface. The colony spreads by growth forces and sliding motility of cells and undergoes cell death followed by subsequent disintegration of the dead cells in the medium. We model cell death by considering two possible situations: In one of the cases, cell death occurs in response to the limitation of local nutrients, while the other case corresponds to an active death process, known as apoptotic or programmed cell death. We demonstrate how the colony morphology is influenced by the presence of cell death. Our results show that cell death facilitates transitions from roughly circular to highly branched structures at the periphery of an expanding colony. Interestingly, our results also reveal that for the colonies which are growing in higher initial nutrient concentrations, cell death occurs much earlier compared to the colonies which are growing in lower initial nutrient concentrations. This work provides new insights into the branched patterning of growing bacterial colonies as a consequence of complex interplay among the biochemical and mechanical effects.

  17. An improved method for staining cell colonies in clonogenic assays

    OpenAIRE

    Guda, Kishore; Natale, Leanna; Markowitz, Sanford D.

    2007-01-01

    Clonogenic assay is a widely used experimental approach to test for the effects of drugs/genes on the growth and proliferative characteristics of cells in vitro. Accurate quantitation of treatment effects in clonogeneic assays depends on the ability to visualize and count cell colonies precisely. We report a novel method (referred as ETeB) for staining cell colonies grown on plastic and specially coated substrates like collagen. Using colon cancer cell lines grown on plastic and collagen, we ...

  18. An improved method for staining cell colonies in clonogenic assays.

    Science.gov (United States)

    Guda, Kishore; Natale, Leanna; Markowitz, Sanford D

    2007-06-01

    Clonogenic assay is a widely used experimental approach to test for the effects of drugs/genes on the growth and proliferative characteristics of cells in vitro. Accurate quantitation of treatment effects in clonogeneic assays depends on the ability to visualize and count cell colonies precisely. We report a novel method (referred as ETeB) for staining cell colonies grown on plastic and specially coated substrates like collagen. Using colon cancer cell lines grown on plastic and collagen, we compared the colony staining efficiencies of the widely used methylene blue, and Ethidium bromide (ETeB) stains. Results show that the ETeB protocol works well on plastic and is extremely effective for staining colonies on collagen when compared to methylene blue. The key features and advantages of ETeB technique are; (a) reduction in background for colonies grown on collagen and possibly other substrates, (b) the whole procedure takes less than a minute, (c) no post-stain washing step is required which eliminates colony losses for cell lines that are loosely adherent, (d) colony visualization and counting can be done immediately following the staining procedure using a standard UV illuminator and software, and (e) the method works across a wide variety of cell lines. The simplicity and robustness of this procedure should warrant its usage in both small and large-scale clonogenic experiments.

  19. Effect of serum from rats with destructed nuclei of the posterior hypothalamus on the formation of hemopoietic colonies in the spleen of lethally irradiated mice after bone marrow cell transplantation

    International Nuclear Information System (INIS)

    Fedorov, N.A.; Likhovetskaya, Z.M.; Kurbanova, G.N.; Prigozhina, T.A.; L'vovich, A.I.

    1982-01-01

    Colony formation capability of serum from animals with destructed nuclei of the posterior hypothalamus was studied in lethally irradiated mice. Male-rats of Wistar line and hybrid mice (CBA x C57 BL) were used in the experiments. The serum from rats with destructed nuclei of the posterior hypothalamus was injected simultaneously with bone marrow transplantation into lethally irradiated mice. The number of macrocolonies in the spleen was counted on the 9th day. It was ascertained that the serum from rats with destructed nuclei of the posterior hypothalamus caused an increase of the number of macroscopically visible colonies in the spleen of lethally irradiated mice. The determination of hemopoetic types of colonies showed that the effect of the serum from those animals caused an increase of the number of granulocytic-type colonies. The initiation of colony stimulating and leukopoetic activity in the blood of animals after the destruction of mammillary body nuclei and posterior hypothalamic nucleus attested, according to the authors point of view, that humoral mediators (humoral mediator) could participated in the mechanism of hypothalamus effect on leulopoiesis

  20. Effect of UV irradiation on macromolecular synthesis and colony formation in Bacteroides fragilis

    International Nuclear Information System (INIS)

    Schumann, J.P.; Jones, D.T.; Woods, D.R.

    1984-01-01

    Irradiation of Bacteroides fragilis cells with far-UV light resulted in the immediate degradation of DNA which continued for 40 to 60 min. During the degradation phase, DNA synthesis was decreased but was never totally inhibited. DNA degradation after irradiation was inhibited by chloramphenicol and caffeine. DNA synthesis in irradiated cells was reduced by chloramphenicol but resumed after 100 min. Irradiated cells continued to synthesize DNA for 40 min in the presence of caffeine but then DNA synthesis was completely inhibited and never recovered. RNA and protein synthesis were decreased by UV irradiation and the degree of inhibition was proportional to the UV dose. Colony formation was not affected immediately by UV irradiation and continued for a dose-dependent period before inhibition. There was an inverse relationship between UV dose and inhibition of colony formatiom which occurred sooner in cells irradiated with lower doses of UV light. The characteristics of DNA synthesis in B. fragilis cells after UV irradiation differ from those in wild-type Escherichia coli cells, where DNA synthesis is stopped immediately by UV irradiation, but resemble those in E. coli recA mutant cells where extensive degradation occurs following UV irradiation. (author)

  1. A novel type of colony formation in marine planktonic diatoms revealed by atomic force microscopy.

    Directory of Open Access Journals (Sweden)

    Sunčica Bosak

    Full Text Available Diatoms have evolved a variety of colonial life forms in which cells are connected by organic threads, mucilage pads or silicate structures. In this study, we provide the first description of a novel strategy of colony formation among marine planktonic diatoms. Bacteriastrum jadranum forms loose but regular chains with distinct heterovalvate terminal cells. The colonial cells and their siliceous projections, the setae, are not in direct contact; instead, they are enclosed within the optically transparent organic matrix. This cell jacket structure was detected by staining procedure with Alcian Blue, which showed that the polysaccharides are predominant matrix constituents and revealed that the jacket reaches the span of the setae. The scanning electron microscopy (SEM observations showed distinguishable fibrillar network firmly associated with cells. Using atomic force microscopy (AFM, we were able to visualise and characterise the cell jacket structure at molecular resolution. At nanoscale resolution, the cell jacket appears as a cross-linked fibrillar network organised into a recognisable structure. The circular patches of self-repeating pattern (hexagonal pores with openings of 8-100 nm are connected through thicker surrounding fibrils and reinforced by branching fibrils. The pore-forming fibrils within the patches are only 0.6-1.6 nm high, the surrounding fibrils connecting patches are 2.0-2.8 nm high, and the branching fibrils are considerably wider but not higher than 4.0 nm. The discovered polysaccharide fibrillar network is highly organised and delicately structured with a monomolecular fibril height of 0.6 nm. We conclude that the Bacteriastrum polysaccharide jacket represents an essential part of the cell, as the conjunction of the polymer network with the frustule appears to be extremely tight and such specific and unique patterns have never been found in self-assembled polysaccharide gel networks, which are usually encountered in the

  2. Video Bioinformatics Analysis of Human Embryonic Stem Cell Colony Growth

    Science.gov (United States)

    Lin, Sabrina; Fonteno, Shawn; Satish, Shruthi; Bhanu, Bir; Talbot, Prue

    2010-01-01

    Because video data are complex and are comprised of many images, mining information from video material is difficult to do without the aid of computer software. Video bioinformatics is a powerful quantitative approach for extracting spatio-temporal data from video images using computer software to perform dating mining and analysis. In this article, we introduce a video bioinformatics method for quantifying the growth of human embryonic stem cells (hESC) by analyzing time-lapse videos collected in a Nikon BioStation CT incubator equipped with a camera for video imaging. In our experiments, hESC colonies that were attached to Matrigel were filmed for 48 hours in the BioStation CT. To determine the rate of growth of these colonies, recipes were developed using CL-Quant software which enables users to extract various types of data from video images. To accurately evaluate colony growth, three recipes were created. The first segmented the image into the colony and background, the second enhanced the image to define colonies throughout the video sequence accurately, and the third measured the number of pixels in the colony over time. The three recipes were run in sequence on video data collected in a BioStation CT to analyze the rate of growth of individual hESC colonies over 48 hours. To verify the truthfulness of the CL-Quant recipes, the same data were analyzed manually using Adobe Photoshop software. When the data obtained using the CL-Quant recipes and Photoshop were compared, results were virtually identical, indicating the CL-Quant recipes were truthful. The method described here could be applied to any video data to measure growth rates of hESC or other cells that grow in colonies. In addition, other video bioinformatics recipes can be developed in the future for other cell processes such as migration, apoptosis, and cell adhesion. PMID:20495527

  3. The time-course relationship between endogenous spleen colony formation and marrow cellularity after midlethal irradiation of mice

    International Nuclear Information System (INIS)

    Koch, I.; Wiktor-Jedrzejczak, W.; Wojskowa Akademia Medyczna, Warsaw

    1981-01-01

    The kinetics of appearance and disappearance of endogenous spleen colonies following 4 and 6 Gy of X-irradiation was compared with the kinetics of changes of cellular contents of femur cavities. Additionally, the effect of postirradiation bleeding and this way of the subsequent increase in the level of endogenous erythropoietin was studied. It was found that the kinetics of endogenous haemopoietic recovery in the marrow follows the same characteristic biphasic pattern as in the spleen although it is slightly delayed in time. First wave of regeneration corresponded in time with the formation of transient endogenous spleen colonies 4-7 days postirradiation, and the 2nd wave corresponded in time witn the formation of classical haemopoietic stem-cell derived endogenous spleen colonies 9-12 days following irradiation. Postirradiation bleeding markedly stimulated particularly the first wave of regeneration both in the marrow and in the spleen. (orig.) [de

  4. Effect of retinoic acid on cell-cell adhesiveness in cloned BHK21/C13 cells which form piling-up colonies.

    Science.gov (United States)

    Kamei, H

    1983-10-01

    The effect was studied of retinoic acid (RA) on cell-cell adhesiveness in Ag8-1 cells, which are piling-up colony-forming cells cloned from a Syrian hamster kidney fibroblastic cell line BHK21/C13. From the piled-up part of the colonies grown with RA (10 microM), many cells were dissociated by mere shaking or pipetting. The dissociated cells soon adhered to and spread on plastic surfaces in the presence of RA. The number of cells per colony increased almost at the same rate in the presence or absence of RA. The effect of RA on the appearance of cells dissociable from colonies was noticeable above 0.1 microM, prominent from 1 to 10 microM, greater when added in the earlier stages of colony formation and negligible when added just before the dissociation assay. Single cells from the monolayer culture grown with RA (10 microM) had less tendency to aggregate than did those from the control culture. Cells from the colonies grown with RA adhered to and spread on a plastic dish for bacterial use, but control cells seldom adhered. These results indicate that RA decreases the cell-cell adhesiveness or suppresses the development of it but increases cell-substratum adhesiveness.

  5. Economies, Moralities, and State Formations in British Colonial India

    OpenAIRE

    Wilson, Nicholas Hoover

    2012-01-01

    How is modern power organized? My dissertation explores this question by probing how state, society, and economy became ethically autonomous spheres for colonial administrators. In other words, I ask how officials shifted justifications for their behavior from referring to their immediate peers to the abstract imperatives of markets, the social, and sovereignty.Corruption scandals were a key cause of this shift. Endemic to the English East India Trading Company's administration in India si...

  6. Sequestration and Distribution Characteristics of Cd(II) by Microcystis aeruginosa and Its Role in Colony Formation.

    Science.gov (United States)

    Bi, Xiangdong; Yan, Ran; Li, Fenxiang; Dai, Wei; Jiao, Kewei; Zhou, Qixing; Liu, Qi

    2016-01-01

    To investigate the sequestration and distribution characteristics of Cd(II) by Microcystis aeruginosa and its role in Microcystis colony formation, M. aeruginosa was exposed to six different Cd(II) concentrations for 10 days. Cd(II) exposure caused hormesis in the growth of M. aeruginosa . Low concentrations of Cd(II) significantly induced formation of small Microcystis colonies ( P bEPS) contents of M. aeruginosa significantly ( P 93% of Cd(II) was sequestrated in the groups with lower added concentrations of Cd(II). More than 80% of the sequestrated Cd(II) was bioadsorbed by bEPS. The Pearson correlation coefficients of exterior and interior factors related to colony formation of M. aeruginosa revealed that Cd(II) could stimulate the production of IPS and bEPS via increasing Cd(II) bioaccumulation and bioadsorption. Increased levels of cross-linking between Cd(II) and bEPS stimulated algal cell aggregation, which eventually promoted the formation of Microcystis colonies.

  7. In vitro effects of fluor-hydroxyapatite, fluorapatite and hydroxyapatite on colony formation, DNA damage and mutagenicity.

    Science.gov (United States)

    Jantová, S; Theiszová, M; Letasiová, S; Birosová, L; Palou, T M

    2008-04-30

    The number of biomaterials used in biomedical applications has rapidly increased in the past two decades. Fluorapatite (FA) is one of the inorganic constituents of bone or teeth used for hard-tissue repairs and replacements. Fluor-hydroxyapatite (FHA) is a new synthetically prepared composite that in its structure contains the same molecular concentration of OH(-) groups and F(-) ions. The aim of this experimental investigation was to evaluate cytotoxic, genotoxic and mutagenic effects of FHA and FA eluates on Chinese hamster V79 cells and to compare them with the effects of hydroxyapatite (HA) eluate. Cytotoxicity of the biomaterials tested was evaluated by use of the cell colony-formation assay and by direct counting of the cells in each colony. Genotoxicity was assessed by single-cell gel electrophoresis (comet assay) and mutagenicity was evaluated by the Hprt gene-mutation assay and in bacterial mutagenicity tests using Salmonella typhimurium TA100. The results show that the highest test concentrations of the biomaterials (100% and 75% eluates) induced very weak inhibition of colony growth (about 10%). On the other hand, the reduction of cell number per colony induced by these concentrations was in the range from 43% to 31%. The comet assay showed that biomaterials induced DNA breaks, which increased with increasing test concentrations in the order HAcell division in V79 cell colonies.

  8. Multiscale modeling of bacterial colonies: how pili mediate the dynamics of single cells and cellular aggregates

    Science.gov (United States)

    Pönisch, Wolfram; Weber, Christoph A.; Juckeland, Guido; Biais, Nicolas; Zaburdaev, Vasily

    2017-01-01

    Neisseria gonorrhoeae is the causative agent of one of the most common sexually transmitted diseases, gonorrhea. Over the past two decades there has been an alarming increase of reported gonorrhea cases where the bacteria were resistant to the most commonly used antibiotics thus prompting for alternative antimicrobial treatment strategies. The crucial step in this and many other bacterial infections is the formation of microcolonies, agglomerates consisting of up to several thousands of cells. The attachment and motility of cells on solid substrates as well as the cell-cell interactions are primarily mediated by type IV pili, long polymeric filaments protruding from the surface of cells. While the crucial role of pili in the assembly of microcolonies has been well recognized, the exact mechanisms of how they govern the formation and dynamics of microcolonies are still poorly understood. Here, we present a computational model of individual cells with explicit pili dynamics, force generation and pili-pili interactions. We employ the model to study a wide range of biological processes, such as the motility of individual cells on a surface, the heterogeneous cell motility within the large cell aggregates, and the merging dynamics and the self-assembly of microcolonies. The results of numerical simulations highlight the central role of pili generated forces in the formation of bacterial colonies and are in agreement with the available experimental observations. The model can quantify the behavior of multicellular bacterial colonies on biologically relevant temporal and spatial scales and can be easily adjusted to include the geometry and pili characteristics of various bacterial species. Ultimately, the combination of the microbiological experimental approach with the in silico model of bacterial colonies might provide new qualitative and quantitative insights on the development of bacterial infections and thus pave the way to new antimicrobial treatments.

  9. Burkholderia cenocepacia ShvR-regulated genes that influence colony morphology, biofilm formation, and virulence.

    Science.gov (United States)

    Subramoni, Sujatha; Nguyen, David T; Sokol, Pamela A

    2011-08-01

    Burkholderia cenocepacia is an opportunistic pathogen that primarily infects cystic fibrosis (CF) patients. Previously, we reported that ShvR, a LysR regulator, influences colony morphology, virulence, and biofilm formation and regulates the expression of an adjacent 24-kb genomic region encoding 24 genes. In this study, we report the functional characterization of selected genes in this region. A Tn5 mutant with shiny colony morphology was identified with a polar mutation in BCAS0208, predicted to encode an acyl-coenzyme A dehydrogenase. Mutagenesis of BCAS0208 and complementation analyses revealed that BCAS0208 is required for rough colony morphology, biofilm formation, and virulence on alfalfa seedlings. It was not possible to complement with BCAS0208 containing a mutation in the catalytic site. BCAS0201, encoding a putative flavin adenine dinucleotide (FAD)-dependent oxidoreductase, and BCAS0207, encoding a putative citrate synthase, do not influence colony morphology but are required for optimum levels of biofilm formation and virulence. Both BCAS0208 and BCAS0201 contribute to pellicle formation, although individual mutations in each of these genes had no appreciable effect on pellicle formation. A mutant with a polar insertion in BCAS0208 was significantly less virulent in a rat model of chronic lung infection as well as in the alfalfa model. Genes in this region were shown to influence utilization of branched-chain fatty acids, tricarboxylic acid cycle substrates, l-arabinose, and branched-chain amino acids. Together, our data show that the ShvR-regulated genes BCAS0208 to BCAS0201 are required for the rough colony morphotype, biofilm and pellicle formation, and virulence in B. cenocepacia.

  10. Characterization of the integrated filamentous phage Pf5 and its involvement in small-colony formation

    NARCIS (Netherlands)

    Mooij, Marlies J.; Drenkard, Eliana; Llamas, María A.; Vandenbroucke-Grauls, Christina M. J. E.; Savelkoul, Paul H. M.; Ausubel, Frederick M.; Bitter, Wilbert

    2007-01-01

    Bacteriophages play an important role in bacterial virulence and phenotypic variation. It has been shown that filamentous bacteriophage Pf4 of Pseudomonas aeruginosa strain PAO1 mediates the formation of small-colony variants (SCVs) in biofilms. This morphology type is associated with parameters of

  11. Contact enhancement of locomotion in spreading cell colonies

    Science.gov (United States)

    D'Alessandro, Joseph; Solon, Alexandre P.; Hayakawa, Yoshinori; Anjard, Christophe; Detcheverry, François; Rieu, Jean-Paul; Rivière, Charlotte

    2017-10-01

    The dispersal of cells from an initially constrained location is a crucial aspect of many physiological phenomena, ranging from morphogenesis to tumour spreading. In such processes, cell-cell interactions may deeply alter the motion of single cells, and in turn the collective dynamics. While contact phenomena like contact inhibition of locomotion are known to come into play at high densities, here we focus on the little explored case of non-cohesive cells at moderate densities. We fully characterize the spreading of micropatterned colonies of Dictyostelium discoideum cells from the complete set of individual trajectories. From data analysis and simulation of an elementary model, we demonstrate that contact interactions act to speed up the early population spreading by promoting individual cells to a state of higher persistence, which constitutes an as-yet unreported contact enhancement of locomotion. Our findings also suggest that the current modelling paradigm of memoryless active particles may need to be extended to account for the history-dependent internal state of motile cells.

  12. Colony Lysate Arrays for Proteomic Profiling of Drug-Tolerant Persisters of Cancer Cell.

    Science.gov (United States)

    Kume, Kohei; Nishizuka, Satoshi S

    2017-09-05

    Functional heterogeneity of cancer cells is one of the key properties to understanding relapse after drug treatment. Hence, clarification is needed with regard to which types of subgroups of cancer cells dominantly contribute to the initiation of relapse. Recently, we established the colony lysate array (CoLA), which is a method that allows comparison of individual colonies at the protein level to assess the initiation of anticancer drug-tolerant persisters (DTPs) based on the reverse-phase protein array (RPPA) system. DTPs grow in various drug concentrations and types showing 2-dimensional growth (∼1 mm) on a flat surface. The size of DTPs are larger than spheroids (∼0.3 mm) in agarose gel, which makes them easy to handle for a number of assays. DTPs provide functional information during the process of their formation, initiating from the origin of a drug-tolerant single cell. Using >2000 DTPs generated from various drugs and doses profiled on the basis of 44 proteins, we demonstrate that the DTPs are clustered on the basis of their proteomic profiles changing in response to drugs and doses. Of interest, nine transcription factors in the DTPs, such as STAT3 and OCT4A, were identified as having decreased or increased levels of proteins in response to gefitinib. Importantly, these results can be obtained only by individual proteomic colony profiling, which may identify alternative therapeutic targets and biomarkers for DTPs that may harbor critical mechanisms for cancer relapse.

  13. A simple colony-formation assay in liquid medium, termed 'tadpoling', provides a sensitive measure of Saccharomyces cerevisiae culture viability.

    Science.gov (United States)

    Welch, Aaron Z; Koshland, Douglas E

    2013-12-01

    Here we describe the first high-throughput amenable method of quantifying Saccharomyces cerevisiae culture viability. Current high-throughput methods of assessing yeast cell viability, such as flow cytometry and SGA analysis, do not measure the percentage viability of a culture but instead measure cell vitality or colony fitness, respectively. We developed a method, called tadpoling, to quantify the percentage viability of a yeast culture, with the ability to detect as few as one viable cell amongst ~10(8) dead cells. The most important feature of this assay is the exploitation of yeast colony formation in liquid medium. Utilizing a microtiter dish, we are able to observe a range of viability of 100% to 0.0001%. Comparison of tadpoling to the traditional plating method to measure yeast culture viability reveals that, for the majority of Saccharomyces species analyzed there is no significant difference between the two methods. In comparison to flow cytometry using propidium iodide, the high-throughput method of measuring yeast culture viability, tadpoling is much more accurate at culture viabilities < 1%. Thus, we show that tadpoling provides an easy, inexpensive, space-saving method, amenable to high-throughput screens, for accurately measuring yeast cell viability. Copyright © 2013 John Wiley & Sons, Ltd.

  14. Vibrio cholerae O1 strain TSI-4 produces the exopolysaccharide materials that determine colony morphology, stress resistance, and biofilm formation.

    Science.gov (United States)

    Wai, S N; Mizunoe, Y; Takade, A; Kawabata, S I; Yoshida, S I

    1998-10-01

    Vibrio cholerae O1 strain TSI-4 (El Tor, Ogawa) can shift to a rugose colony morphology from its normal translucent colony morphology in response to nutrient starvation. We have investigated differences between the rugose and translucent forms of V. cholerae O1 strain TSI-4. Electron microscopic examination of the rugose form of TSI-4 (TSI-4/R) revealed thick, electron-dense exopolysaccharide materials surrounding polycationic ferritin-stained cells, while the ferritin-stained material was absent around the translucent form of TSI-4 (TSI-4/T). The exopolysaccharide produced by V. cholerae TSI-4/R was found to have a composition of N-acetyl-D-glucosamine, D-mannose, 6-deoxy-D-galactose, and D-galactose (7.4:10.2:2.4:3.0). The expression of an amorphous exopolysaccharide promotes biofilm development under static culture conditions. Biofilm formation by the rugose strain was determined by scanning electron microscopy, and most of the surface of the film was colonized by actively dividing rod cells. The corresponding rugose and translucent strains were compared for stress resistance. By having exopolysaccharide materials, the rugose strains acquired resistance to osmotic and oxidative stress. Our data indicated that an exopolysaccharide material on the surface of the rugose strain promoted biofilm formation and resistance to the effects of two stressing agents.

  15. Radiosensitivity of mice and its modifiers based on the endogeneous spleen colony formation

    Energy Technology Data Exchange (ETDEWEB)

    Kobayashi, Jindo; Wagatuma, Kaoru

    1987-02-01

    In irradiated mouse hematopoietic tissue, there is a group of cells which can proliferate and form macroscopic colonies. In the spleen, the colonies formed in this manner are discrete and easy to count. In order to look into a difference of radiosensitivity between male and female and the mechanisms of the modification, such as protective agent and hormones on radiosensitivity, the spleen colony forming (SCF) is used as an indicator of reactions in the x-rays irradiated mice. A linear decrease was found in SCF depended on x-rays dose. From the colony forming after irradiation the male was more radiosensitive than female. AET protected from the injury depended on the radiation dose in male mice, but in female mice, protection effects were not observed. Gonatropin showed protective effects for radiation injury on high dose irradiation both in male and female mice. Adrenaline showed similar effects as Gonatropin. Insuline showed a negative effects of protection on 400 R irradiation, while on 600 R irradiation, protective effects were observed.

  16. Are self-ligating brackets related to less formation of Streptococcus mutans colonies? A systematic review

    Directory of Open Access Journals (Sweden)

    Leonard Euler Andrade Gomes do Nascimento

    2014-01-01

    Full Text Available OBJECTIVE: To verify, by means of a systematic review, whether the design of brackets (conventional or self-ligating influences adhesion and formation of Streptococcus mutans colonies. METHODS: Search strategy: four databases (Cochrane Central Register of Controlled Trials, Ovid ALL EMB Reviews, PubMed and BIREME were selected to search relevant articles covering the period from January 1965 to December 2012. Selection Criteria: in first consensus by reading the title and abstract. The full text was obtained from publications that met the inclusion criteria. Data collection and analysis: Two reviewers independently extracted data using the keywords: conventional, self-ligating, biofilm, Streptococcus mutans, and systematic review; and independently evaluated the quality of the studies. In case of divergence, the technique of consensus was adopted. RESULTS: The search strategy resulted in 1,401 articles. The classification of scientific relevance revealed the high quality of the 6 eligible articles of which outcomes were not unanimous in reporting not only the influence of the design of the brackets (conventional or self-ligating over adhesion and formation of colonies of Streptococcus mutans, but also that other factors such as the quality of the bracket type, the level of individual oral hygiene, bonding and age may have greater influence. Statistical analysis was not feasible because of the heterogeneous methodological design. CONCLUSIONS: Within the limitations of this study, it was concluded that there is no evidence for a possible influence of the design of the brackets (conventional or self-ligating over colony formation and adhesion of Streptococcus mutans.

  17. Antigen 43 from Escherichia coli induces inter- and intraspecies cell aggregation and changes in colony morphology of Pseudomonas fluorescens

    DEFF Research Database (Denmark)

    Kjærgaard, Kristian; Schembri, Mark; Hasman, Henrik

    2000-01-01

    with a distinct frizzy colony morphology in E. coli. Here we show that Ag43 can be expressed in a functional form on the surface of the environmentally important Pseudomonas fluorescens strain SBW25 with ensuing cell aggregation and frizzy colony types. Using green fluorescence protein-tagged cells, we......Antigen 43 (Ag43) is a surface-displayed autotransporter protein of Escherichia coli. By virtue of its self-association characteristics, this protein is able to mediate autoaggregation and flocculation off. coli cells in static cultures. Additionally, surface display of Ag43 is associated...... demonstrate that Ag43 can be used as a tool to provide interspecies cell aggregation between E. coli and P. fluorescens. Furthermore, Ag43 expression enhances biofilm formation in P. fluorescens to glass surfaces. The versatility of this protein was also reflected in Ag43 surface display in a variety of other...

  18. Effect of Granulocyte-Colony Stimulating Factor on Endothelial Cells and Osteoblasts

    Directory of Open Access Journals (Sweden)

    Xi Ling Liu

    2016-01-01

    Full Text Available Objectives. Some animal studies showed that granulocyte-colony stimulating factor (G-CSF provides beneficial environment for bone healing. It has been well documented that endothelial cells and osteoblasts play critical roles in multiple phases of bone healing. However, the biological effects of G-CSF on these cells remain controversial. This study aimed to investigate the influence of G-CSF at various concentrations on endothelial cells and osteoblasts. Materials and Methods. Human umbilical vein endothelial cells (HUVECs and human osteoblasts (hOBs were treated with G-CSF at 1000, 100, 10, and 0 ng/mL, respectively. The capacity of cell proliferation, migration, and tube formation of HUVECs was evaluated at 72, 8, and 6 hours after treatment, respectively. The capacity of proliferation, differentiation, and mineralization of hOBs was evaluated at 24 hours, 72 hours, and 21 days after treatment, respectively. Results. HUVECs treated with 100 and 1000 ng/mL G-CSF showed a significantly higher value comparing with controls in migration assay (p<0.001, p<0.01, resp.; the group treated with 1000 ng/mL G-CSF showed a significantly lower value on tube formation. No significant difference was detected in groups of hOBs. Conclusions. G-CSF showed favorable effects only on the migration of HUVECs, and no direct influence was found on hOBs.

  19. Endogenous Sheet-Averaged Tension Within a Large Epithelial Cell Colony.

    Science.gov (United States)

    Dumbali, Sandeep P; Mei, Lanju; Qian, Shizhi; Maruthamuthu, Venkat

    2017-10-01

    Epithelial cells form quasi-two-dimensional sheets that function as contractile media to effect tissue shape changes during development and homeostasis. Endogenously generated intrasheet tension is a driver of such changes, but has predominantly been measured in the presence of directional migration. The nature of epithelial cell-generated forces transmitted over supracellular distances, in the absence of directional migration, is thus largely unclear. In this report, we consider large epithelial cell colonies which are archetypical multicell collectives with extensive cell-cell contacts but with a symmetric (circular) boundary. Using the traction force imbalance method (TFIM) (traction force microscopy combined with physical force balance), we first show that one can determine the colony-level endogenous sheet forces exerted at the midline by one half of the colony on the other half with no prior assumptions on the uniformity of the mechanical properties of the cell sheet. Importantly, we find that this colony-level sheet force exhibits large variations with orientation-the difference between the maximum and minimum sheet force is comparable to the average sheet force itself. Furthermore, the sheet force at the colony midline is largely tensile but the shear component exhibits significantly more variation with orientation. We thus show that even an unperturbed epithelial colony with a symmetric boundary shows significant directional variation in the endogenous sheet tension and shear forces that subsist at the colony level.

  20. Application of Artificial Bee Colony in Model Parameter Identification of Solar Cells

    Directory of Open Access Journals (Sweden)

    Rongjie Wang

    2015-07-01

    Full Text Available The identification of values of solar cell parameters is of great interest for evaluating solar cell performances. The algorithm of an artificial bee colony was used to extract model parameters of solar cells from current-voltage characteristics. Firstly, the best-so-for mechanism was introduced to the original artificial bee colony. Then, a method was proposed to identify parameters for a single diode model and double diode model using this improved artificial bee colony. Experimental results clearly demonstrate the effectiveness of the proposed method and its superior performance compared to other competing methods.

  1. Surface Topography Guides Morphology and Spatial Patterning of Induced Pluripotent Stem Cell Colonies

    Directory of Open Access Journals (Sweden)

    Giulio Abagnale

    2017-08-01

    Full Text Available The relevance of topographic cues for commitment of induced pluripotent stem cells (iPSCs is largely unknown. In this study, we demonstrate that groove-ridge structures with a periodicity in the submicrometer range induce elongation of iPSC colonies, guide the orientation of apical actin fibers, and direct the polarity of cell division. Elongation of iPSC colonies impacts also on their intrinsic molecular patterning, which seems to be orchestrated from the rim of the colonies. BMP4-induced differentiation is enhanced in elongated colonies, and the submicron grooves impact on the spatial modulation of YAP activity upon induction with this morphogen. Interestingly, TAZ, a YAP paralog, shows distinct cytoskeletal localization in iPSCs. These findings demonstrate that topography can guide orientation and organization of iPSC colonies, which may affect the interaction between mechanosensors and mechanotransducers in iPSCs.

  2. Stimulation and support of haemopoietic stem cell proliferation by irradiated stroma cell colonies in bone marrow cell culture in vitro

    International Nuclear Information System (INIS)

    Mori, K.J.; Izumi, Hiroko; Seto, Akira

    1981-01-01

    A culture system was established in which haemopoietic stem cells can undergo a recovery proliferation after a depletion of the stem cells, completely in vitro. To elucidate the source of the stimulatory factors, normal bone marrow cells were overlayed on top of the irradiated adherent 'stromal' cell colonies in the bone marrow cell culture. This stimulated the proliferation of haemopoietic stem cells in the cultured cells in suspension. The present results indicate that the stromal cells produce factors which stimulate stem cell proliferation. Whether the stimulation is evoked by direct cell-cell interactions or by humoral factors is as yet to be studied. (author)

  3. 'Demonstrating the machine guns' : rebellion, violence and state formation in early colonial Darfur.

    OpenAIRE

    Vaughan, Christopher

    2014-01-01

    Recent literature on British colonial rule in Africa has increasingly emphasised the ways in which relatively cautious colonial states were formed in processes of engagement and accommodation with local societies. This article uses the example of a major rebellion against colonial authority in southern Darfur in 1921 to demonstrate the ways in which these processes of local engagement might themselves feed into rebellion against state authority, rather than secure colonial rule. The rebellion...

  4. Bionomics and formation of "Bonsai" colonies with long term rearing of Coptotermes formosanus (Isoptera: Rhinotermitidae)

    Science.gov (United States)

    This laboratory study reports the ability of Formosan subterranean termite, Coptotermes formosanus Shiraki, colonies to survive for at least 9-yr while restricted to a sweater box. Colonies survived by limiting queen size and worker numbers, allowing these bonsai colonies to thrive. Queen physogastr...

  5. Peripheral blood cells from children with RASopathies show enhanced spontaneous colonies growth in vitro and hyperactive RAS signaling

    International Nuclear Information System (INIS)

    Gaipa, G; Bugarin, C; Cianci, P; Sarno, J; Bonaccorso, P; Biondi, A; Selicorni, A

    2015-01-01

    Germline mutations in genes coding for molecules involved in the RAS/RAF/MEK/ERK pathway are the hallmarks of a newly classified family of autosomal dominant syndromes termed RASopathies. Myeloproliferative disorders (MPDs), in particular, juvenile myelomonocytic leukemia, can lead to potentially severe complications in children with Noonan syndrome (NS). We studied 27 children with NS or other RASopathies and 35 age-matched children as control subjects. Peripheral blood (PB) cells from these patients were studied for in vitro colony-forming units (CFUs) activity, as well as for intracellular phosphosignaling. Higher spontaneous growth of both burst-forming units-erythroid (BFU-E) and CFU-granulocyte/macrophage (CFU-GM) colonies from RAS-mutated patients were observed as compared with control subjects. We also observed a significantly higher amount of GM-colony-stimulating factor-induced p-ERK in children with RASopathies. Our findings demonstrate for the first time that PB cells isolated from children suffering from NS or other RASopathies without MPD display enhanced BFU-E and CFU-GM colony formation in vitro. The biological significance of these findings clearly awaits further studies. Collectively, our data provide a basis for further investigating of only partially characterized hematological alterations present in children suffering from RASopathies, and may provide new markers for progression toward malignant MPD in these patients

  6. Metabolic diversification of cells during the development of yeast colonies

    Czech Academy of Sciences Publication Activity Database

    Váchová, Libuše; Kučerová, Helena; Devaux, F.; Úlehlová, M.; Palková, Z.

    2009-01-01

    Roč. 11, č. 2 (2009), s. 494-504 ISSN 1462-2912 R&D Projects: GA ČR GA204/05/0294; GA ČR GA204/08/0718; GA MŠk(CZ) LC531 Grant - others:GB(GB) Howard Hughes Medical Institute International Research Award Institutional research plan: CEZ:AV0Z50200510 Keywords : yeast * yeast colonies * saccharomyces cerevisiae Subject RIV: EE - Microbiology , Virology Impact factor: 4.909, year: 2009

  7. DECREASED LEVEL OF CORD BLOOD CIRCULATING ENDOTHELIAL COLONY-FORMING CELLS IN PREECLAMPSIA

    Science.gov (United States)

    Muñoz-Hernandez, Rocio; Miranda, Maria L.; Stiefel, Pablo; Lin, Ruei-Zeng; Praena-Fernández, Juan M.; Dominguez-Simeon, Maria J.; Villar, Jose; Moreno-Luna, Rafael; Melero-Martin, Juan M.

    2014-01-01

    Preeclampsia is a pregnancy-related disorder associated with increased cardiovascular risk for the offspring. Endothelial colony-forming cells (ECFCs) are a subset of circulating endothelial progenitor cells that participate in the formation of vasculature during development. However, the effect of preeclampsia on fetal levels of ECFCs is largely unknown. In this study, we sought to determine whether cord blood ECFC abundance and function are altered in preeclampsia. We conducted a prospective cohort study that included women with normal (n=35) and preeclamptic (n=15) pregnancies. We measured ECFC levels in the umbilical cord blood of neonates and characterized ECFC phenotype, cloning-forming ability, proliferation and migration towards VEGF-A and FGF-2, in vitro formation of capillary-like structures, and in vivo vasculogenic ability in immunodeficient mice. We found that the level of cord blood ECFCs was statistically lower in preeclampsia than in control pregnancies (P = .04), a reduction that was independent of other obstetric factors. In addition, cord blood ECFCs from preeclamptic pregnancies required more time to emerge in culture than control ECFCs. However, once derived in culture, ECFC function was deemed normal and highly similar between preeclampsia and control, including the ability to form vascular networks in vivo. This study demonstrates that preeclampsia affects ECFC abundance in neonates. A reduced level of ECFCs during preeclamptic pregnancies may contribute to an increased risk of developing future cardiovascular events. PMID:24752434

  8. Changes in epidermal radiosensitivity with time associated with increased colony numbers

    NARCIS (Netherlands)

    G.J.M.J. van den Aardweg (Gerard J. M.); G.M. Morris; A. Bywaters; E.J. Bakker (Erik Jan); W.J. Mooi (Wolter)

    2001-01-01

    textabstractEpidermal clonogenic cell survival and colony formation following irradiation were investigated and related to radiosensitivity. A rapid in vivo/in vitro assay was developed for the quantification of colonies arising from surviving clonogenic cells in pig

  9. Impact of chlorine on the cell integrity and toxin release and degradation of colonial Microcystis.

    Science.gov (United States)

    Fan, Jiajia; Rao, La; Chiu, Yi-Ting; Lin, Tsair-Fuh

    2016-10-01

    The occurrence of toxic cyanobacteria in drinking water sources is problematic for water authorities as they can impair drinking water quality. Chlorine as a commonly used oxidant in water treatment plants has shown the potential to lyse cyanobacterial cells, resulting in the release of secondary metabolites which are hard to be removed during conventional water treatment processes. The majority of cyanobacterial species such as Microcystis, often occur in colonial forms under natural conditions. However, previous studies have mainly focused on the influence of chlorination on individual cyanobacterial cells due to technique limitations. A syringe dispersion method combined with a fluorescence technique (SYTOX Green stain with flow cytometry), was successfully developed for the evaluation of cell integrity of colonial Microcystis. Chlorination of Microcystis-laden water was conducted at different chlorine dosages for different colonial sizes (mucilage. There was a lag phase before cell rupture occurred and a Delayed Chick Watson Model describes the experimental data very well for the kinetics of cyanobacterial cell rupture. The growing colonial size caused increases in the lag phases but decreases in the cell lysis rates. Chlorination also induced the release of microcystins (MCs) from colonial Microcystis cells. In particular, increased levels of dissolved MCs were observed in Cheng Kung Lake (CKL) water. In summary, the reaction of chlorine with colonial cyanobacteria is more complicated than with individual cells. The efficiency of chlorine oxidation could be reduced by the cell-bound mucilage and natural water matrix. These observations may provide insights for water authorities to assess the risk to drinking water quality posed by chlorination under natural conditions. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. Microprinted Stem Cell Niches Reveal Compounding Effect of Colony Size on Stromal Cells-Mediated Neural Differentiation.

    Science.gov (United States)

    Joshi, Ramila; Thakuri, Pradip Shahi; Buchanan, James C; Li, Jun; Tavana, Hossein

    2018-03-01

    Microenvironmental factors have a major impact on differentiation of embryonic stem cells (ESCs). Here, a novel phenomenon that size of ESC colonies has a significant regulatory role on stromal cells induced differentiation of ESCs to neural cells is reported. Using a robotic cell microprinting technology, defined densities of ESCs are confined within aqueous nanodrops over a layer of supporting stromal cells immersed in a second, immiscible aqueous phase to generate ESC colonies of defined sizes. Temporal protein and gene expression studies demonstrate that larger ESC colonies generate disproportionally more neural cells and longer neurite processes. Unlike previous studies that attribute neural differentiation of ESCs solely to interactions with stromal cells, it is found that increased intercellular signaling of ESCs significantly enhances neural differentiation. This study offers an approach to generate neural cells with improved efficiency for potential use in translational research. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Detection of colony-stimulating factor messenger RNA in single T cells by in situ hybridization

    DEFF Research Database (Denmark)

    Williamson, D J; Owens, T; Pearse, M

    1989-01-01

    In situ hybridization has been used to study the accumulation of colony-stimulating factor (CSF) mRNA in single cells of a T lymphocyte clone (E9.D4) following antibody-mediated (F23.1) activation via the Ti-T3 complex in filler-independent bulk cultures. The specificity of hybridization for cell...

  12. Smooth muscle progenitor cells from peripheral blood promote the neovascularization of endothelial colony-forming cells

    Energy Technology Data Exchange (ETDEWEB)

    Joo, Hyung Joon; Seo, Ha-Rim [Department of Cardiology, Cardiovascular Center, College of Medicine, Korea University, Seoul (Korea, Republic of); Jeong, Hyo Eun [Department of Mechanical Engineering, Korea University, Seoul (Korea, Republic of); Choi, Seung-Cheol; Park, Jae Hyung; Yu, Cheol Woong; Hong, Soon Jun [Department of Cardiology, Cardiovascular Center, College of Medicine, Korea University, Seoul (Korea, Republic of); Chung, Seok [Department of Mechanical Engineering, Korea University, Seoul (Korea, Republic of); Lim, Do-Sun, E-mail: dslmd@kumc.or.kr [Department of Cardiology, Cardiovascular Center, College of Medicine, Korea University, Seoul (Korea, Republic of)

    2014-07-11

    Highlights: • Two distinct vascular progenitor cells are induced from adult peripheral blood. • ECFCs induce vascular structures in vitro and in vivo. • SMPCs augment the in vitro and in vivo angiogenic potential of ECFCs. • Both cell types have synergistic therapeutic potential in ischemic hindlimb model. - Abstract: Proangiogenic cell therapy using autologous progenitors is a promising strategy for treating ischemic disease. Considering that neovascularization is a harmonized cellular process that involves both endothelial cells and vascular smooth muscle cells, peripheral blood-originating endothelial colony-forming cells (ECFCs) and smooth muscle progenitor cells (SMPCs), which are similar to mature endothelial cells and vascular smooth muscle cells, could be attractive cellular candidates to achieve therapeutic neovascularization. We successfully induced populations of two different vascular progenitor cells (ECFCs and SMPCs) from adult peripheral blood. Both progenitor cell types expressed endothelial-specific or smooth muscle-specific genes and markers, respectively. In a protein array focused on angiogenic cytokines, SMPCs demonstrated significantly higher expression of bFGF, EGF, TIMP2, ENA78, and TIMP1 compared to ECFCs. Conditioned medium from SMPCs and co-culture with SMPCs revealed that SMPCs promoted cell proliferation, migration, and the in vitro angiogenesis of ECFCs. Finally, co-transplantation of ECFCs and SMPCs induced robust in vivo neovascularization, as well as improved blood perfusion and tissue repair, in a mouse ischemic hindlimb model. Taken together, we have provided the first evidence of a cell therapy strategy for therapeutic neovascularization using two different types of autologous progenitors (ECFCs and SMPCs) derived from adult peripheral blood.

  13. Isolation of endothelial colony-forming cells from blood samples collected from the jugular and cephalic veins of healthy adult horses.

    Science.gov (United States)

    Sharpe, Ashley N; Seeto, Wen J; Winter, Randolph L; Zhong, Qiao; Lipke, Elizabeth A; Wooldridge, Anne A

    2016-10-01

    OBJECTIVE To evaluate optimal isolation of endothelial colony-forming cells (ECFCs) from peripheral blood of horses. SAMPLE Jugular and cephalic venous blood samples from 17 adult horses. PROCEDURES Each blood sample was divided; isolation was performed with whole blood adherence (WBA) and density gradient centrifugation (DGC). Isolated cells were characterized by uptake of 1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate-labeled acetylated low-density lipoprotein (DiI-Ac-LDL), vascular tubule formation, and expression of endothelial (CD34, CD105, vascular endothelial growth factor receptor-2, and von Willebrand factor) and hematopoietic (CD14) cell markers by use of indirect immunofluorescence assay (IFA) and flow cytometry. RESULTS Colonies with cobblestone morphology were isolated from 15 of 17 horses. Blood collected from the cephalic vein yielded colonies significantly more often (14/17 horses) than did blood collected from the jugular vein (8/17 horses). Of 14 cephalic blood samples with colonies, 13 were obtained with DGC and 8 with WBA. Of 8 jugular blood samples with colonies, 8 were obtained with DGC and 4 with WBA. Colony frequency (colonies per milliliter of blood) was significantly higher for cephalic blood samples and samples isolated with DGC. Cells formed vascular tubules, had uptake of DiI-Ac-LDL, and expressed endothelial markers by use of IFA and flow cytometry, which confirmed their identity as ECFCs. CONCLUSIONS AND CLINICAL RELEVANCE Maximum yield of ECFCs was obtained for blood samples collected from both the jugular and cephalic veins and use of DGC to isolate cells. Consistent yield of ECFCs from peripheral blood of horses will enable studies to evaluate diagnostic and therapeutic uses.

  14. Patterns of proliferation and differentiation of irradiated haemopoietic stem cells cultured on normal 'stromal' cell colonies in vitro

    International Nuclear Information System (INIS)

    Mori, K.J.

    1981-01-01

    Experiments were designed to elucidate whether or not the irradiated bone marrow cells receive any stimulation for the self-replication and differentiation from normal 'stromal' cell colonies in the bone marrow cell culture in vitro. When irradiated or unirradiated bone marrow cells were overlaid on the normal adherent cell colonies, the proliferation of haemopoietic stem cells was supported, the degree of the stimulation depending on the starting cellular concentration. There was, however, no significant changes in the concentration of either CFUs or CFUc regardless of the dose of irradiation on the bone marrow cells overlaid. This was a great contrast to the dose-dependent decrease of CFUs or CFUc within the culture in which both the stem cells and stromal cells were simultaneously irradiated. These results suggest that the balance of self-replication and differentiation of the haemopoietic stem cells is affected only when haemopoietic microenvironment is perturbed. (author)

  15. Colony Dimorphism in Bradyrhizobium Strains

    Science.gov (United States)

    Sylvester-Bradley, Rosemary; Thornton, Philip; Jones, Peter

    1988-01-01

    Ten isolates of Bradyrhizobium spp. which form two colony types were studied; the isolates originated from a range of legume species. The two colony types differed in the amount of gum formed or size or both, depending on the strain. Whole 7-day-old colonies of each type were subcultured to determine the proportion of cells which had changed to the other type. An iterative computerized procedure was used to determine the rate of switching per generation between the two types and to predict proportions reached at equilibrium for each strain. The predicted proportions of the wetter (more gummy) or larger colony type at equilibrium differed significantly between strains, ranging from 0.9999 (strain CIAT 2383) to 0.0216 (strain CIAT 2469), because some strains switched faster from dry to wet (or small to large) and others switched faster from wet to dry (or large to small). Predicted equilibrium was reached after about 140 generations in strain USDA 76. In all but one strain (CIAT 3030) the growth rate of the wetter colony type was greater than or similar to that of the drier type. The mean difference in generation time between the two colony types was 0.37 h. Doubling times calculated for either colony type after 7 days of growth on the agar surface ranged from 6.0 to 7.3 h. The formation of two persistent colony types by one strain (clonal or colony dimorphism) may be a common phenomenon among Bradyrhizobium strains. Images PMID:16347599

  16. Heterogeneity within the spleen colony-forming cell population in rat bone marrow

    International Nuclear Information System (INIS)

    Martens, A.C.; van Bekkum, D.W.; Hagenbeek, A.

    1986-01-01

    The pluripotent hemopoietic stem cell (HSC) of the rat can be enumerated in a spleen colony assay (SCA) in rats as well as mice. After injection of rat bone marrow into lethally irradiated mice, macroscopically visible spleen colonies (CFU-S) are found from day 6 through 14, but the number varies on consecutive days. In normal bone marrow a constant ratio of day-8 to day-12 colony numbers is observed. However, this ratio is changed after in vivo treatment of rats with cyclophosphamide, as well as after in vitro treatment of rat bone marrow with cyclophosphamide derivatives. This indicates that the CFU-S that form colonies on day 8 react differently to this treatment than the CFU-S that form colonies on day 12, and suggests heterogeneity among the CFU-S population. Posttreatment regrowth of day-8 and day-12 CFU-S is characterized by differences in population-doubling times (Td = 0.85 days vs 1.65 days). Another argument in support of the postulate of heterogeneity within the rat CFU-S population is derived from the fact that (in contrast to normal rat spleen) the spleen of leukemic rats contains high numbers of CFU-S that show a ratio of day-8 to day-12 CFU-S of 4.5, which is different than that observed for a CFU-S population in normal bone marrow (a ratio of 2.4). It is concluded that, in rat hemopoiesis, two populations of spleen colony-forming cells can be distinguished using the rat-to-mouse SCA. This indicates that mouse and rat hemopoiesis are comparable in this respect and that heterogeneity in the stem cell compartment is a general phenomenon

  17. Chinua Achebe and the Post-colonial Esthetic: Writing, Identity, and National Formation

    Directory of Open Access Journals (Sweden)

    Simon Gikandi

    1991-01-01

    Full Text Available Chinua Achebe is recognized as one of Africa's most important and influential writers, and his novels have focused on the ways in which the European tradition of the novel and African modes of expression relate to each other in both complementary and contesting ways. Achebe's novels are informed by an important theory of writing which tries to mediate the politics of the novel as a form of commentary on the emergence and transformation of nationalism which constitutes the African writer's epistemological context. Achebe's esthetic has been overdetermined by the changing discourse on representation and national identity in colonial and post-colonial Africa. His anxious quest for a post-colonial esthetic is predicated on the belief that narrative can enable the writer to express an alternative order of things opposed to realities imprisoned by imperialism and Western domination.

  18. Maternal Body-Mass Index and Cord Blood Circulating Endothelial Colony-Forming Cells

    Science.gov (United States)

    Lin, Ruei-Zeng; Miranda, Maria L.; Vallejo-Vaz, Antonio J.; Stiefel, Pablo; Praena-Fernández, Juan M.; Bernal-Bermejo, Jose; Jimenez-Jimenez, Luis M.; Villar, Jose; Melero-Martin, Juan M.

    2013-01-01

    Objective Endothelial colony-forming cells (ECFCs) are a subset of circulating endothelial progenitor cells that are particularly abundant in umbilical cord blood. We sought to determine whether ECFC abundance in cord blood is associated with maternal body-mass index (BMI) in non-pathological pregnancies. Study design We measured the level of ECFCs in the cord blood of neonates (n=27) born from non-obese healthy mothers with non-pathological pregnancies and examined whether ECFC abundance correlated with maternal BMI. We also examined the effect of maternal BMI on ECFC phenotype and function using angiogenic and vasculogenic assays. Results We observed variation in ECFC abundance among subjects and found a positive correlation between pre-pregnancy maternal BMI and ECFC content (r=0.51, P=0.007), which was independent of other obstetric factors. Despite this variation, ECFC phenotype and functionality were deemed normal and highly similar between subjects with maternal BMI <25 kg/m2 and BMI between 25–30 kg/m2, including the ability to form vascular networks in vivo. Conclusions This study underlines the need to consider maternal BMI as a potential confounding factor for cord blood levels of ECFCs in future comparative studies between healthy and pathological pregnancies. Endothelial colony-forming cells (ECFCs) are a subset of progenitor cells that circulate in peripheral blood and can give rise to endothelial cells (1,2), contributing to the formation of new vasculature and the maintenance of vascular integrity (3–5). The mechanisms that regulate the abundance of these cells in vivo remain poorly understood. ECFCs are rare in adult peripheral blood (1,2,10). In contrast, there is an elevated number of these cells in fetal blood during the third trimester of pregnancy (11–13). Emerging evidence indicates that deleterious conditions during fetal life can impair ECFC content and function. For instance, offspring of diabetic mothers have been shown to have

  19. Absence of a relationship between immunophenotypic and colony enumeration analysis of endothelial progenitor cells in clinical haematopoietic cell sources

    Directory of Open Access Journals (Sweden)

    Turner Marc L

    2007-07-01

    Full Text Available Abstract Background The discovery of adult endothelial progenitor cells (EPC offers potential for vascular regenerative therapies. The expression of CD34 and VEGFR2 by EPC indicates a close relationship with haematopoietic progenitor cells (HPC, and HPC-rich sources have been used to treat cardiac and limb ischaemias with apparent clinical benefit. However, the laboratory characterisation of the vasculogenic capability of potential or actual therapeutic cell autograft sources is uncertain since the description of EPC remains elusive. Various definitions of EPC based on phenotype and more recently on colony formation (CFU-EPC have been proposed. Methods We determined EPC as defined by proposed phenotype definitions (flow cytometry and by CFU-EPC in HPC-rich sources: bone marrow (BM; cord blood (CB; and G-CSF-mobilised peripheral blood (mPB, and in HPC-poor normal peripheral blood (nPB. Results As expected, the highest numbers of cells expressing the HPC markers CD34 or CD133 were found in mPB and least in nPB. The proportions of CD34+ cells co-expressing CD133 is of the order mPB>CB>BM≈nPB. CD34+ cells co-expressing VEGFR2 were also most frequent in mPB. In contrast, CFU-EPC were virtually absent in mPB and were most readily detected in nPB, the source lowest in HPC. Conclusion HPC sources differ in their content of putative EPC. Normal peripheral blood, poor in HPC and in HPC-related phenotypically defined EPC, is the richest source of CFU-EPC, suggesting no direct relationship between the proposed EPC immunophenotypes and CFU-EPC potential. It is not apparent whether either of these EPC measurements, or any, is an appropriate indicator of the therapeutic vasculogenic potential of autologous HSC sources.

  20. Simulating biological processes: stochastic physics from whole cells to colonies

    Science.gov (United States)

    Earnest, Tyler M.; Cole, John A.; Luthey-Schulten, Zaida

    2018-05-01

    The last few decades have revealed the living cell to be a crowded spatially heterogeneous space teeming with biomolecules whose concentrations and activities are governed by intrinsically random forces. It is from this randomness, however, that a vast array of precisely timed and intricately coordinated biological functions emerge that give rise to the complex forms and behaviors we see in the biosphere around us. This seemingly paradoxical nature of life has drawn the interest of an increasing number of physicists, and recent years have seen stochastic modeling grow into a major subdiscipline within biological physics. Here we review some of the major advances that have shaped our understanding of stochasticity in biology. We begin with some historical context, outlining a string of important experimental results that motivated the development of stochastic modeling. We then embark upon a fairly rigorous treatment of the simulation methods that are currently available for the treatment of stochastic biological models, with an eye toward comparing and contrasting their realms of applicability, and the care that must be taken when parameterizing them. Following that, we describe how stochasticity impacts several key biological functions, including transcription, translation, ribosome biogenesis, chromosome replication, and metabolism, before considering how the functions may be coupled into a comprehensive model of a ‘minimal cell’. Finally, we close with our expectation for the future of the field, focusing on how mesoscopic stochastic methods may be augmented with atomic-scale molecular modeling approaches in order to understand life across a range of length and time scales.

  1. Tryptophan-Dependent Control of Colony Formation After DNA Damage via Sea3-Regulated TORC1 Signaling in Saccharomyces cerevisiae.

    Science.gov (United States)

    Polleys, Erica J; Bertuch, Alison A

    2015-05-04

    The Saccharomyces cerevisiae Iml1 complex inhibits TORC1 signaling and SEACAT antagonizes the Iml1 complex. Conditions in which SEACAT functions to inhibit Iml1 and, hence, TORC1 signaling, remain largely unknown. The SEACAT member Sea3 was linked previously to telomere maintenance and DNA repair via genome-wide genetic and physical interaction studies. Therefore, we questioned whether Sea3 functioned through TORC1 to influence these pathways. Deletion of SEA3 delayed the emergence of telomerase-independent survivors that use break-induced replication (BIR) to maintain their telomeres. Similarly, sea3∆ mutants exhibited a delay in colony formation in a BIR assay strain after double-strand break (DSB) induction as well as on the DNA-damaging agent bleomycin. Deletion of IML1 rescued the impaired growth of sea3∆ mutants after DNA damage, consistent with Sea3 functioning as a regulator of TORC1 signaling. The delay was not attributable to slowed DSB repair or termination of the DNA damage checkpoint but to tryptophan auxotrophy. High levels of tryptophan in yeast peptone dextrose media did not rescue the delay in colony formation, suggesting a defect in tryptophan import, although levels of the high-affinity tryptophan permease Tat2 were not perturbed in the sea3Δ mutant. Addition of quinolinic acid, an intermediate of the de novo NAD+ biosynthetic pathway, however, rescued the delay in colony formation in the sea3Δ mutant. Together, these findings highlight the importance of enforcement of TORC1 signaling and suggest that internal tryptophan levels influence growth recovery post DNA damage through the role of tryptophan in NAD+ synthesis. Copyright © 2015 Polleys and Bertuch.

  2. Heterogeneity of the radiosensitivity and origins of tissue macrophage colony-forming cells

    Energy Technology Data Exchange (ETDEWEB)

    Oghiso, Yoichi; Yamada, Yutaka (National Inst. of Radiological Sciences, Chiba (Japan))

    1992-12-01

    Previous studies suggest that the radiosensitivity and origin of tissue macrophage precursors differ from those of hemopoietic macrophage colony-forming units (CFU-Ms) committed to macrophage-lineage cells. We assessed the origins of tissue macrophage colony-forming cells (M-CFCs) in mice by comparing their kinetics and radiosensitivities in the normal steady state and under the conditions of bone marrow depletion by [sup 89]Sr-administration and/or splenectomy. The results indicate that the radiosensitive peritoneal M-CFCs elicited by thioglycollate are derived from bone marrow macrophage precursors; where as alveolar M-CFCs, which are radioresistant, are self-sustained locally and independent of hemopoietic macrophage precursors. In contrast, highly radiosensitive liver M-CFCs are probably derived from CFU-Ms that appear to be propagated in the spleen in association with hemopoietic responses. (author).

  3. Hemopoiesis in mouse heterozygous for the W trait. Difference in postirradiation recovery related to the defect in formation of transient endogenous spleen colonies

    International Nuclear Information System (INIS)

    Wiktor-Jedrzejczak, W.; Urbanowska, E.; Szczylik, C.; Siekierzynski, M.; Pojda, Z.

    1985-01-01

    The hemopoietic regeneration following midlethal irradiation in Wsup(v)/+ mice had similarly biphasic kinetics as in their hematologically normal +/+ littermates. The first abortive phase of regeneration was either severly reduced (formation of transient endogenous spleen colonies, reticulocyte count, granulocyte count) or absent (spleen and femur cellularity, platelet count, PCV) in Wsup(v)/+ mice, when compared to +/+ mice. The second phase leading to permanent recovery of hemopoiesis was in Wsup(v)/+ mice delayed in time. Moreover, although to a lesser extent the values of spleen and femur cellularity, PCV and platelet count were decreased in Wsup(v)/+ mice. Postirradiation bleeding, which stimulated particularly the 1st phase of regeneration both in Wsup(v)/+ and +/+ mice did not lead to the minimization of differences between above two genotypes. It is suggested that the observed differences in the abortive regeneration between Wsup(v)/+ and +/+ mice are primarily dependent on the presence in Wsup(v)/+ mice of selective defect of transient endogeneous colony forming units (TE-CFUs). Moreover, it is possible that the differences in the second phase of regeneration leading to permanent recovery are secondarily dependent on the TE-CFUs defect, as most probably the TE-CFU is the step in stem cell differentiation to mature cells. (orig.) [de

  4. Metabolic differentiation of surface and invasive cells of yeast colony biofilms revealed by gene expression profiling

    Czech Academy of Sciences Publication Activity Database

    Maršíková, J.; Wilkinson, D.; Hlaváček, Otakar; Gilfillan, G.D.; Mizeranschi, A.; Hughes, T.; Begany, Markéta; Rešetárová, Stanislava; Váchová, Libuše; Palková, Z.

    2017-01-01

    Roč. 18, OCT 23 (2017), s. 814 ISSN 1471-2164 R&D Projects: GA MŠk(CZ) 7F14083; GA MŠk(CZ) LQ1604; GA MŠk(CZ) ED1.1.00/02.0109 Institutional support: RVO:61388971 Keywords : Saccharomyces cerevisiae * Colony biofilms * Cell differentiation Subject RIV: EE - Microbiology, Virology OBOR OECD: Microbiology Impact factor: 3.729, year: 2016

  5. Effects of lead(II) on the extracellular polysaccharide (EPS) production and colony formation of cultured Microcystis aeruginosa.

    Science.gov (United States)

    Bi, Xiang-dong; Zhang, Shu-lin; Dai, Wei; Xing, Ke-zhing; Yang, Fan

    2013-01-01

    To investigate the effects of lead(II) on the production of extracellular polysaccharides (EPS), including bound extracellular polysaccharides (bEPS) and soluble extracellular polysaccharides (sEPS), and the colony formation of Microcystis aeruginosa, cultures of M. aeruginosa were exposed to four concentrations (5.0, 10.0, 20.0 and 40.0 mg/L) of lead(II) for 10 d under controlled laboratory conditions. The results showed that 5.0 and 10.0 mg/L lead(II) stimulated M. aeruginosa growth throughout the experiment while 20.0 and 40.0 mg/L lead(II) inhibited M. aeruginosa growth in the first 2 d exposure and then stimulated it. As compared to the control group, significant increases in the bEPS and sEPS production were observed in 20.0 and 40.0 mg/L lead(II) treatments (P bEPS production, which conversely promoted colony formation, suggesting that heavy metals might be contributing to the bloom-forming of M. aeruginosa in natural conditions.

  6. Grazing impacts of the invasive bivalve Limnoperna fortunei (Dunker, 1857 on single-celled, colonial and filamentous cyanobacteria

    Directory of Open Access Journals (Sweden)

    V Gazulha

    Full Text Available Feeding behavior of the invasive bivalve Limnoperna fortunei in the presence of single-celled, colonial, and filamentous cyanobacteria was tested in laboratory experiments to evaluate the effects of size and shape on mussel feeding. The first hypothesis holds that golden mussel filters more efficiently smaller particles, such as single cells of Microcystis, which could be more easily assimilated by its filtering apparatus. The second hypothesis sustains that L. fortunei filters more efficiently rounded colonies, such as Microcystis, which would be more easily ingested than lengthy filamentous, such as Planktothrix. Filtration rates of golden mussel in the presence of single-celled, colonial and filamentous cyanobacteria were similar. Nevertheless, there was a great difference in the ingestion and pseudofeces production rates. Single cells were widely accepted as food, while filamentous and colonial cyanobacteria were massively expelled as pseudofeces. The results confirmed the first hypothesis that golden mussel prefers to ingest smaller particles. The second hypothesis was rejected since filamentous were preferentially ingested than colonial cyanobacteria. Golden mussel has the potential to remove toxic cells (Microcystis, however this potential would be reduced in cyanobacteria blooms, where colonial forms which are preferentially rejected by L. fortunei, are predominant. In this case, the presence of this invasive bivalve could also enhance the occurrence of blooms by rejecting colonial and filamentous cyanobacteria in pseudofeces.

  7. Altered Proteome of Burkholderia pseudomallei Colony Variants Induced by Exposure to Human Lung Epithelial Cells.

    Directory of Open Access Journals (Sweden)

    Anis Rageh Al-Maleki

    Full Text Available Burkholderia pseudomallei primary diagnostic cultures demonstrate colony morphology variation associated with expression of virulence and adaptation proteins. This study aims to examine the ability of B. pseudomallei colony variants (wild type [WT] and small colony variant [SCV] to survive and replicate intracellularly in A549 cells and to identify the alterations in the protein expression of these variants, post-exposure to the A549 cells. Intracellular survival and cytotoxicity assays were performed followed by proteomics analysis using two-dimensional gel electrophoresis. B. pseudomallei SCV survive longer than the WT. During post-exposure, among 259 and 260 protein spots of SCV and WT, respectively, 19 were differentially expressed. Among SCV post-exposure up-regulated proteins, glyceraldehyde 3-phosphate dehydrogenase, fructose-bisphosphate aldolase (CbbA and betaine aldehyde dehydrogenase were associated with adhesion and virulence. Among the down-regulated proteins, enolase (Eno is implicated in adhesion and virulence. Additionally, post-exposure expression profiles of both variants were compared with pre-exposure. In WT pre- vs post-exposure, 36 proteins were differentially expressed. Of the up-regulated proteins, translocator protein, Eno, nucleoside diphosphate kinase (Ndk, ferritin Dps-family DNA binding protein and peptidyl-prolyl cis-trans isomerase B were implicated in invasion and virulence. In SCV pre- vs post-exposure, 27 proteins were differentially expressed. Among the up-regulated proteins, flagellin, Eno, CbbA, Ndk and phenylacetate-coenzyme A ligase have similarly been implicated in adhesion, invasion. Protein profiles differences post-exposure provide insights into association between morphotypic and phenotypic characteristics of colony variants, strengthening the role of B. pseudomallei morphotypes in pathogenesis of melioidosis.

  8. Doxorubicin resistance mediated by cytoplasmic macrophage colony-stimulating factor is associated with switch from apoptosis to autophagic cell death in MCF-7 breast cancer cells

    Science.gov (United States)

    Zhang, Mengxia; Zhang, Hailiang; Tang, Fan; Wang, Yuhua; Mo, Zhongcheng; Lei, Xiaoyong

    2016-01-01

    Macrophage colony-stimulating factor is a vital factor in maintaining the biological function of monocyte–macrophage lineage. It is expressed in many tumor tissues and cancer cells. Recent findings indicate that macrophage colony-stimulating factor might contribute to chemoresistance, but the precise mechanisms are unclear. This study was to explore the effect of macrophage colony-stimulating factor on doxorubicin resistance in MCF-7 breast cancer cells and the possible mechanism. In the study, the human breast cancer cells, MCF-7, were transfected with macrophage colony-stimulating factor. We document that cytoplasmic macrophage colony-stimulating factor induces doxorubicin resistance and inhibits apoptosis in MCF-7 cells. Further studies demonstrated that cytoplasmic macrophage colony-stimulating factor-mediated apoptosis inhibition was dependent on the activation of PI3K/Akt/Survivin pathway. More importantly, we found that macrophage colony-stimulating factor-induced autophagic cell death in doxorubicin-treated MCF-7 cells. Taken together, we show for the first time that macrophage colony-stimulating factor-induced doxorubicin resistance is associated with the changes in cell death response with defective apoptosis and promotion of autophagic cell death. PMID:27439542

  9. High-Throughput Quantification of Bacterial-Cell Interactions Using Virtual Colony Counts

    Directory of Open Access Journals (Sweden)

    Stefanie Hoffmann

    2018-02-01

    Full Text Available The quantification of bacteria in cell culture infection models is of paramount importance for the characterization of host-pathogen interactions and pathogenicity factors involved. The standard to enumerate bacteria in these assays is plating of a dilution series on solid agar and counting of the resulting colony forming units (CFU. In contrast, the virtual colony count (VCC method is a high-throughput compatible alternative with minimized manual input. Based on the recording of quantitative growth kinetics, VCC relates the time to reach a given absorbance threshold to the initial cell count using a series of calibration curves. Here, we adapted the VCC method using the model organism Salmonella enterica sv. Typhimurium (S. Typhimurium in combination with established cell culture-based infection models. For HeLa infections, a direct side-by-side comparison showed a good correlation of VCC with CFU counting after plating. For MDCK cells and RAW macrophages we found that VCC reproduced the expected phenotypes of different S. Typhimurium mutants. Furthermore, we demonstrated the use of VCC to test the inhibition of Salmonella invasion by the probiotic E. coli strain Nissle 1917. Taken together, VCC provides a flexible, label-free, automation-compatible methodology to quantify bacteria in in vitro infection assays.

  10. Simulation of Cell Group Formation Regulated by Coordination Number, Cell Cycle and Duplication Frequency

    Directory of Open Access Journals (Sweden)

    Shigehiro Hashimoto

    2013-08-01

    Full Text Available The effects of coordination number, a cell cycle and duplication frequency on cell-group formation have been investigated in a computer simulation. In the simulation, multiplication occurs in the last three steps of a cell cycle with a probability function to give variations in the interval. Each cell has a constant coordination number: four or six. When a cell gets surrounded by adjacent cells, its status changes from an active stage to a resting stage. Each cell repeats multiplication, and disappears when the times of multiplication reach to the limit. Variation was made in the coordination number, in the interval of multiplication and in the limited times of multiplication. The cells of the colony, which have the larger number of coordination, have reached the larger maximum population and disappeared earlier.

  11. Bionomics and Formation of “Bonsai” Colonies With Long-Term Rearing of Coptotermes formosanus (Isoptera: Rhinotermitidae).

    Science.gov (United States)

    Osbrink, W L A; Cornelius, M L; Showler, A T

    2016-04-01

    This laboratory study reports the ability of Formosan subterranean termite, Coptotermes formosanus Shiraki, colonies to survive for at least 9 yr while restricted to a sweater box. Colonies survived by limiting queen size and worker numbers, allowing these bonsai colonies to thrive. Queen physogastry appeared to plateau with 9-yr-old queens not larger than 6-yr-old queens, but nearly triple the size of 2-yr-old queens. Nine-year-old colony worker numbers were not greater than 6-yr-old colonies, but worker numbers were greater than in 2-yr-old colonies. Such colony survival under conditions of restricted resources provides a mechanism for re-infestation of areas following extensive area-wide control efforts. “Bonsai” colonies are relevant to the ability of marginalized colonies to avoid detection and then expand and invade into areas once the large, mature colonies are eliminated, and their potential to produce alates to start new C. formosanus colonies in areas which have been subjected to colony elimination programs impacts termite management strategies.

  12. Role of distinct dimorphic transitions in territory colonizing and formation of yeast colony architecture

    Czech Academy of Sciences Publication Activity Database

    Vopálenská, I.; Šťovíček, V.; Janderová, B.; Váchová, Libuše; Palková, Z.

    2010-01-01

    Roč. 12, č. 1 (2010), s. 264-277 ISSN 1462-2912 R&D Projects: GA AV ČR IAA500200506 Institutional research plan: CEZ:AV0Z50200510 Keywords : SACCHAROMYCES-CEREVISIAE * CANDIDA - ALBICANS * PSEUDOHYPHAE FORMATION Subject RIV: EE - Microbiology, Virology Impact factor: 5.537, year: 2010

  13. The Process of State Formation in Pre-Colonial East Africa. | Ugwu ...

    African Journals Online (AJOL)

    This size was due to the rapid expansion through agriculture, annexation of smaller kingdoms and strong formation of a strong and standing army as well as the ... Africa, and indeed along the common frontier between the two regions, it is difficult to determine with precision exactly where one begins and the other ends.

  14. Mechanisms for T cell tolerance induced with granulocyte colony-stimulating factor.

    Science.gov (United States)

    Yang, Jian-Zhu; Zhang, Jin-Qiao; Sun, Li-Xia

    2016-02-01

    Granulocyte colony-stimulating factor (G-CSF) has been widely accepted as a mediator of T cell tolerance. The immune modulatory effect of G-CSF on T cells is believed to be mediated exclusively through other effector cells, such as monocytes, tolerogenic dendritic cells (DC), and myeloid-derived suppressor cells. Recent advances confirmed the direct effects of G-CSF in inducing immune tolerance of T cells through the G-CSF-G-CSF receptor pathway and related molecular mechanisms. This review aims to summarize the findings associated with the direct and indirect mechanisms for T cell tolerance induced with G-CSF. The role of G-CSF in preventing graft-versus-host disease (GVHD) and in treating autoimmune diseases (ADs) is also discussed. It is conceivable that G-CSF and immune cell compositions, such as tolerogenic DC and CD4(+)CD25(+)Foxp3(+) T cells, modulated by G-CSF could become an integral part of the immunomodulatory therapies against GVHD and ADs in the future. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Implementation of the Bee Colony Optimization method for the design of fuel cells; Implementacion del metodo Bee Colony Optimization para el diseno de celdas de combustible

    Energy Technology Data Exchange (ETDEWEB)

    Esquivel E, J.; Ortiz S, J. J., E-mail: jaime.esquivel@fi.uaemex.mx [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2011-11-15

    The present work shows the results obtained after applying the Bee Colony Optimization algorithm in the design of fuel cells for a BWR. The algorithm that is implemented, works following the behavior that have the bees when pollinating a flowers field. The bees carry out an exhaustive analysis in the cell, so they leave generating diverse configurations where different fuel bars are placed with different uranium enrichments to reach a value mean, with a specific number of gadolinium bars. The behavior of the generated cell is evaluated by means of the use of the commercial code CASMO-4, which shows the variables that allow fixing if the cell fulfills the requirements. Such variables are the local potential peak factor and the neutrons multiplication factor in an infinite medium. (Author)

  16. Effect of leukaemic sera & cell-extracts on splenic colony counts (CFU-S).

    Science.gov (United States)

    Gupta, S; Rusia, U; Agarwal, S; Sood, S K

    1991-08-01

    Sera and leukaemic cell extracts from patients of acute leukaemia were evaluated for their effect on the repopulating ability of the pluripotent stem cells and erythroid differentiation by an in vivo splenic colony count (CFU-S) technique. Normal donor marrow cells of mice were treated with sera and cell extracts from patients of acute leukaemic and healthy controls and injected in the recipient mice. The CFU-S performed on the seventh day to assess repopulating ability of the stem cell showed consistently lower CFU-S counts in the test groups, with leukaemic sera (P less than 0.01) as well as leukaemic cell-extracts (P less than 0.001). The erythroid differentiation assessed by 59Fe uptake by the spleens also showed significantly reduced counts in the two test groups (P less than 0.01 and less than 0.001 respectively). The results indicate that both leukaemic sera and cell-extracts exert a significant suppressive effect on the repopulating ability of the stem cells and on their erythroid differentiation.

  17. Area-based cell colony surviving fraction evaluation: A novel fully automatic approach using general-purpose acquisition hardware.

    Science.gov (United States)

    Militello, Carmelo; Rundo, Leonardo; Conti, Vincenzo; Minafra, Luigi; Cammarata, Francesco Paolo; Mauri, Giancarlo; Gilardi, Maria Carla; Porcino, Nunziatina

    2017-10-01

    The current methodology for the Surviving Fraction (SF) measurement in clonogenic assay, which is a technique to study the anti-proliferative effect of treatments on cell cultures, involves manual counting of cell colony forming units. This procedure is operator-dependent and error-prone. Moreover, the identification of the exact colony number is often not feasible due to the high growth rate leading to the adjacent colony merging. As a matter of fact, conventional assessment does not deal with the colony size, which is generally correlated with the delivered radiation dose or the administered cytotoxic agent. Considering that the Area Covered by Colony (ACC) is proportional to the colony number and size as well as to the growth rate, we propose a novel fully automatic approach exploiting Circle Hough Transform, to automatically detect the wells in the plate, and local adaptive thresholding, which calculates the percentage of ACC for the SF quantification. This measurement relies just on this covering percentage and does not consider the colony number, preventing inconsistencies due to intra- and inter-operator variability. To evaluate the accuracy of the proposed approach, we compared the SFs obtained by our automatic ACC-based method against the conventional counting procedure. The achieved results (r = 0.9791 and r = 0.9682 on MCF7 and MCF10A cells, respectively) showed values highly correlated with the measurements using the traditional approach based on colony number alone. The proposed computer-assisted methodology could be integrated in laboratory practice as an expert system for the SF evaluation in clonogenic assays. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Visualization of morphological categories of colonies for monitoring of effect on induced pluripotent stem cell culture status

    Directory of Open Access Journals (Sweden)

    Risako Nagasaka

    2017-06-01

    Full Text Available From the recent advances, there are growing expectations toward the mass production of induced pluripotent stem cells (iPSCs for varieties of applications. For such type of industrial cell manufacturing, the technology which can stabilize the production efficiency is strongly required. Since the present iPSC culture is covered by delicate manual operations, there are still quality differences in produced cells from same culture protocols. To monitor the culture process of iPSCs with the quantified data to evaluate the culture status, we here introduce image-based visualization method of morphological diversity of iPSC colonies. We have set three types of experiments to evaluate the influential factors in iPSC culture technique that may disturb the undifferentiation status of iPSC colonies: (Exp. 1 technical differences in passage skills, (Exp. 2 technical differences in feeder cell preparation, and (Exp. 3 technical differences in maintenance skills (medium exchange frequency with the combination of manual removal of morphologically irregular colonies. By measuring the all existing colonies from real-time microscopic images, the heterogenous change of colony morphologies in the culture vessel was visualized. By such visualization with morphologically categorized Manhattan chart, the difference between technical skills could be compared for evaluating appropriate cell processing.

  19. The use of granulocyte-colony stimulating factor induced mobilization for isolation of dental pulp stem cells with high regenerative potential.

    Science.gov (United States)

    Murakami, Masashi; Horibe, Hiroshi; Iohara, Koichiro; Hayashi, Yuki; Osako, Yohei; Takei, Yoshifumi; Nakata, Kazuhiko; Motoyama, Noboru; Kurita, Kenichi; Nakashima, Misako

    2013-12-01

    Human dental pulp stem cells (DPSCs) contain subsets of progenitor/stem cells with high angiogenic, neurogenic and regenerative potential useful for cell therapy. It is essential to develop a safe and efficacious method to isolate the clinical-grade DPSCs subsets from a small amount of pulp tissue without using conventional flow cytometry. Thus, a method for isolation of DPSCs subsets based on their migratory response to optimized concentration of 100 ng/ml of granulocyte-colony stimulating factor (G-CSF) was determined in this study. The DPSCs mobilized by G-CSF (MDPSCs) were enriched for CD105, C-X-C chemokine receptor type 4 (CXCR-4) and G-CSF receptor (G-CSFR) positive cells, demonstrating stem cell properties including high proliferation rate and stability. The absence of abnormalities/aberrations in karyotype and lack of tumor formation after transplantation in an immunodeficient mouse were demonstrated. The conditioned medium of MDPSCs exhibited anti-apoptotic activity, enhanced migration and immunomodulatory properties. Furthermore, transplantation of MDPSCs accelerated vasculogenesis in an ischemic hindlimb model and augmented regenerated pulp tissue in an ectopic tooth root model compared to that of colony-derived DPSCs, indicating higher regenerative potential of MDPSCs. In conclusion, this isolation method for DPSCs subsets is safe and efficacious, having utility for potential clinical applications to autologous cell transplantation. Copyright © 2013 Elsevier Ltd. All rights reserved.

  20. Therapeutic Potential of Human-Derived Endothelial Colony-Forming Cells in Animal Models.

    Science.gov (United States)

    Tasev, Dimitar; Koolwijk, Pieter; van Hinsbergh, Victor W M

    2016-10-01

    Tissue regeneration requires proper vascularization. In vivo studies identified that the endothelial colony-forming cells (ECFCs), a subtype of endothelial progenitor cells that can be isolated from umbilical cord or peripheral blood, represent a promising cell source for therapeutic neovascularization. ECFCs not only are able to initiate and facilitate neovascularization in diseased tissue but also can, by acting in a paracrine manner, contribute to the creation of favorable conditions for efficient and appropriate differentiation of tissue-resident stem or progenitor cells. This review outlines the progress in the field of in vivo regenerative and tissue engineering studies and surveys why, when, and how ECFCs can be used for tissue regeneration. Reviewed literature that regard human-derived ECFCs in xenogeneic animal models implicates that ECFCs should be considered as an endothelial cell source of preference for induction of neovascularization. Their neovascularization and regenerative potential is augmented in combination with other types of stem or progenitor cells. Biocompatible scaffolds prevascularized with ECFCs interconnect faster and better with the host vasculature. The physical incorporation of ECFCs in newly formed blood vessels grants prolonged release of trophic factors of interest, which also makes ECFCs an interesting cell source candidate for gene therapy and delivery of bioactive compounds in targeted area. ECFCs possess all biological features to be considered as a cell source of preference for tissue engineering and repair of blood supply. Investigation of regenerative potential of ECFCs in autologous settings in large animal models before clinical application is the next step to clearly outline the most efficient strategy for using ECFCs as treatment.

  1. Branch to colony trajectory in a modular organism: pattern formation in the Indo-Pacific coral Stylophora pistillata.

    Science.gov (United States)

    Shaish, Lee; Abelson, Avigdor; Rinkevich, Baruch

    2006-08-01

    The architecture of the colony in a branching coral is an iterative process in which new layers of calcium carbonate compile atop existing structures that remain unchanged. Colony growth and development, known as astogeny, is believed to be a continuous process, characterized by replication of lower rank unites, polyps, and branches. This study seeks to explore the genetic blueprint of branch-to-colony developmental trajectory in the branching coral Stylophora pistillata, within an astogeny period of 1 year. One hundred small branches (initially 2-4 cm long) were sampled from 10 colonies. A year later, 63 remaining colonies were analyzed for their architectural rules by using 15 morphometric parameters. Multivariate statistical tests were preformed. Cluster and two-dimensional nonmetric Multi-Dimensional Scaling analyses revealed that the 10 genotypes could be divided into two major morphometric groups and two intermediate groups, whereas SIMPER analyses (a similarity percentage test) on within-genet similarities showed high similarity between the ramets developed from each of the 10 genotypes. Although, at first, it seemed that different colonies exhibited variable and different architectural designs (each characterized by specific morphometric parameters), a comprehensive analysis revealed that all 10 coral genotypes exhibited a single common developmental plan that was characterized by a continuum of architectural design with several distinct stages. Each stage is marked by its own characteristic morphometric parameters. Changing of developmental rules during the trajectory from branch to coral colony may help the colony to cope better with environmental constraints.

  2. Growth of a radiation-transformed clone of C3H 1OT1/2 cells into melanin-producing colonies

    Energy Technology Data Exchange (ETDEWEB)

    Szekely, J.G.; Raaphorst, G.P.; Lobreau, A.U.; Azzam, E.I.; Vadasz, J.A.

    1985-01-01

    When R25, a radiation-transformed clone of C3H 1OT1/2 cells, was plated in soft agarose, a fraction of the colonies became pigmented. The morphologies of the white and dark colonies and their cells were compared by optical, transmission and scanning electron microscopy. The transformed R25 cells had apparently differentiated into melanin-producing cells in the soft agarose, with the white colonies containing actively growing cells having only a few melanosomes, and the dark colonies being made up of stationary-phase cells filled with electronopaque melanosomes. Exposure of the R25 cells to 4.0 Gy of X-rays decreased the percentage of dark colonies, while exposure to 1% DMSO had no effect.

  3. OCT4 expression in outgrowth colonies derived from porcine inner cell masses and epiblasts.

    Science.gov (United States)

    Wolf, X A; Rasmussen, M A; Schauser, K; Jensen, A T; Schmidt, M; Hyttel, P

    2011-06-01

    The present study was conducted to test different methods for porcine inner cell mass (ICM) and epiblast isolation and to evaluate the morphology and expression of pluripotency genes in ICM- and epiblast-derived outgrowth colonies (OCs) and passages thereof with particular attention on the relationship between OCT4 expression and embryonic stem cell (ESC)-like morphology. A total of 104 zona pellucida-enclosed and 101 hatched blastocysts were subjected to four different methods of ICM and epiblast isolation, respectively: Manual isolation, immunosurgery, immunosurgery with manual cleaning, or whole blastocyst culture. OCs were established on mouse embryonic fibroblast (MEF) cells and categorized according to morphology and OCT4 staining. Although all isolation methods resulted in ESC-like OCs, immunosurgery with manual cleaning yielded significantly higher rates of ICM/epiblast attachment and subsequent ESC-like morphology, whereas no significant difference was found between ICM and epiblasts with respect to these characteristics. All ESC-like OCs showed nuclear OCT4 staining and expression of OCT4, NANOG and SOX2 as evaluated by RT-PCR. Upon initial passages, the expression of pluripotency markers was, however, gradually lost in spite of maintained ESC-like morphology. In conclusion, we have established a robust system for derivation of ESC-like OCs from porcine ICM and epiblasts and we have shown that localization of OCT4 is associated with an ESC-like morphology although this relationship is lost during early passages. © 2010 Blackwell Verlag GmbH.

  4. Interactions of erythropoietin, granulocyte colony-stimulating factor, stem cell factor, and interleukin-11 on murine hematopoiesis during simultaneous administration

    NARCIS (Netherlands)

    Roeder, [No Value; de Haan, G; Engel, C; Nijhof, W; Dontje, B; Loeffler, M

    1998-01-01

    We investigated how in vivo effects of single hematopoietic cytokines change if given in combination for a prolonged time. Mice were treated with every combination of recombinant human (rh) erythropoietin (EPO), rh granulocyte colony-stimulating factor (G-CSF), recombinant rat (rr) stem cell factor

  5. Stem cell mobilization by granulocyte colony-stimulating factor for myocardial recovery after acute myocardial infarction: a meta-analysis

    DEFF Research Database (Denmark)

    Zohlnhofer, D.; Dibra, A.; Koppara, T.

    2008-01-01

    OBJECTIVES: The objective of this meta-analysis was to evaluate the effect of stem cell mobilization by granulocyte colony-stimulating factor (G-CSF) on myocardial regeneration on the basis of a synthesis of the data generated by randomized, controlled clinical trials of G-CSF after acute...

  6. YfiBNR mediates cyclic di-GMP dependent small colony variant formation and persistence in Pseudomonas aeruginosa.

    Directory of Open Access Journals (Sweden)

    Jacob G Malone

    2010-03-01

    Full Text Available During long-term cystic fibrosis lung infections, Pseudomonas aeruginosa undergoes genetic adaptation resulting in progressively increased persistence and the generation of adaptive colony morphotypes. This includes small colony variants (SCVs, auto-aggregative, hyper-adherent cells whose appearance correlates with poor lung function and persistence of infection. The SCV morphotype is strongly linked to elevated levels of cyclic-di-GMP, a ubiquitous bacterial second messenger that regulates the transition between motile and sessile, cooperative lifestyles. A genetic screen in PA01 for SCV-related loci identified the yfiBNR operon, encoding a tripartite signaling module that regulates c-di-GMP levels in P. aeruginosa. Subsequent analysis determined that YfiN is a membrane-integral diguanylate cyclase whose activity is tightly controlled by YfiR, a small periplasmic protein, and the OmpA/Pal-like outer-membrane lipoprotein YfiB. Exopolysaccharide synthesis was identified as the principal downstream target for YfiBNR, with increased production of Pel and Psl exopolysaccharides responsible for many characteristic SCV behaviors. An yfi-dependent SCV was isolated from the sputum of a CF patient. Consequently, the effect of the SCV morphology on persistence of infection was analyzed in vitro and in vivo using the YfiN-mediated SCV as a representative strain. The SCV strain exhibited strong, exopolysaccharide-dependent resistance to nematode scavenging and macrophage phagocytosis. Furthermore, the SCV strain effectively persisted over many weeks in mouse infection models, despite exhibiting a marked fitness disadvantage in vitro. Exposure to sub-inhibitory concentrations of antibiotics significantly decreased both the number of suppressors arising, and the relative fitness disadvantage of the SCV mutant in vitro, suggesting that the SCV persistence phenotype may play a more important role during antimicrobial chemotherapy. This study establishes Yfi

  7. Effect of adrenalectomy on recipients of allogeneic lymphocytes on inactivation of endogenous colony-forming cells in mice

    International Nuclear Information System (INIS)

    Semenkov, V.F.

    1985-01-01

    This paper presents a study of the killer functions of lymph node cells directed against endogenous colony-forming cells in adrenalectomized recipients in a genetic system with one-way incompatibility: parental line - F 1 hybrid. Mice were irradiated with Co 60 gamma rays on the EGO-2 apparatus with dose rate from 200 to 250 R/min. The results were subjected to statistical analysis by Student's test. It can be tentatively suggested that the killer action of T lymphocytes on endogenous colonies was intensified in adrenal-ectomized recipients with endogenous hypocorticism, as a result of cooperation with the cortisol-sensitive subpopulation of T helper cells, of a change in the properties of the antigen-recognizing receptors, or an increase in the sensitivity of target cells to the killer action of T lymphocytes

  8. Swarming and complex pattern formation in Paenibacillus vortex studied by imaging and tracking cells

    Directory of Open Access Journals (Sweden)

    Jacob Eshel

    2008-02-01

    Full Text Available Abstract Background Swarming motility allows microorganisms to move rapidly over surfaces. The Gram-positive bacterium Paenibacillus vortex exhibits advanced cooperative motility on agar plates resulting in intricate colonial patterns with geometries that are highly sensitive to the environment. The cellular mechanisms that underpin the complex multicellular organization of such a simple organism are not well understood. Results Swarming by P. vortex was studied by real-time light microscopy, by in situ scanning electron microscopy and by tracking the spread of antibiotic-resistant cells within antibiotic-sensitive colonies. When swarming, P. vortex was found to be peritrichously flagellated. Swarming by the curved cells of P. vortex occurred on an extremely wide range of media and agar concentrations (0.3 to 2.2% w/v. At high agar concentrations (> 1% w/v rotating colonies formed that could be detached from the main mass of cells by withdrawal of cells into the latter. On lower percentage agars, cells moved in an extended network composed of interconnected "snakes" with short-term collision avoidance and sensitivity to extracts from swarming cells. P. vortex formed single Petri dish-wide "supercolonies" with a colony-wide exchange of motile cells. Swarming cells were coupled by rapidly forming, reversible and non-rigid connections to form a loose raft, apparently connected via flagella. Inhibitors of swarming (p-Nitrophenylglycerol and Congo Red were identified. Mitomycin C was used to trigger filamentation without inhibiting growth or swarming; this facilitated dissection of the detail of swarming. Mitomycin C treatment resulted in malcoordinated swarming and abortive side branch formation and a strong tendency by a subpopulation of the cells to form minimal rotating aggregates of only a few cells. Conclusion P. vortex creates complex macroscopic colonies within which there is considerable reflux and movement and interaction of cells. Cell

  9. Granulocyte colony-stimulating factor treatment ameliorates lupus nephritis through the expansion of regulatory T cells.

    Science.gov (United States)

    Yan, Ji-Jing; Jambaldorj, Enkthuya; Lee, Jae-Ghi; Jang, Joon Young; Shim, Jung Min; Han, Miyeun; Koo, Tai Yeon; Ahn, Curie; Yang, Jaeseok

    2016-11-15

    Granulocyte colony-stimulating factor (G-CSF) can induce regulatory T cells (Tregs) as well as myeloid-derived suppressor cells (MDSCs). Despite the immune modulatory effects of G-CSF, results of G-CSF treatment in systemic lupus erythematosus are still controversial. We therefore investigated whether G-CSF can ameliorate lupus nephritis and studied the underlying mechanisms. NZB/W F1 female mice were treated with G-CSF or phosphate-buffered saline for 5 consecutive days every week from 24 weeks of age, and were analyzed at 36 weeks of age. G-CSF treatment decreased proteinuria and serum anti-dsDNA, increased serum complement component 3 (C3), and attenuated renal tissue injury including deposition of IgG and C3. G-CSF treatment also decreased serum levels of BUN and creatinine, and ultimately decreased mortality of NZB/W F1 mice. G-CSF treatment induced expansion of CD4 + CD25 + Foxp3 + Tregs, with decreased renal infiltration of T cells, B cells, inflammatory granulocytes and monocytes in both kidneys and spleen. G-CSF treatment also decreased expression levels of MCP-1, IL-6, IL-2, and IL-10 in renal tissues as well as serum levels of MCP-1, IL-6, TNF-α, IL-10, and IL-17. When Tregs were depleted by PC61 treatment, G-CSF-mediated protective effects on lupus nephritis were abrogated. G-CSF treatment ameliorated lupus nephritis through the preferential expansion of CD4 + CD25 + Foxp3 + Tregs. Therefore, G-CSF has a therapeutic potential for lupus nephritis.

  10. Deep vector-based convolutional neural network approach for automatic recognition of colonies of induced pluripotent stem cells.

    Directory of Open Access Journals (Sweden)

    Muthu Subash Kavitha

    Full Text Available Pluripotent stem cells can potentially be used in clinical applications as a model for studying disease progress. This tracking of disease-causing events in cells requires constant assessment of the quality of stem cells. Existing approaches are inadequate for robust and automated differentiation of stem cell colonies. In this study, we developed a new model of vector-based convolutional neural network (V-CNN with respect to extracted features of the induced pluripotent stem cell (iPSC colony for distinguishing colony characteristics. A transfer function from the feature vectors to the virtual image was generated at the front of the CNN in order for classification of feature vectors of healthy and unhealthy colonies. The robustness of the proposed V-CNN model in distinguishing colonies was compared with that of the competitive support vector machine (SVM classifier based on morphological, textural, and combined features. Additionally, five-fold cross-validation was used to investigate the performance of the V-CNN model. The precision, recall, and F-measure values of the V-CNN model were comparatively higher than those of the SVM classifier, with a range of 87-93%, indicating fewer false positives and false negative rates. Furthermore, for determining the quality of colonies, the V-CNN model showed higher accuracy values based on morphological (95.5%, textural (91.0%, and combined (93.2% features than those estimated with the SVM classifier (86.7, 83.3, and 83.4%, respectively. Similarly, the accuracy of the feature sets using five-fold cross-validation was above 90% for the V-CNN model, whereas that yielded by the SVM model was in the range of 75-77%. We thus concluded that the proposed V-CNN model outperforms the conventional SVM classifier, which strongly suggests that it as a reliable framework for robust colony classification of iPSCs. It can also serve as a cost-effective quality recognition tool during culture and other experimental

  11. Molecular Mechanisms Regulating Cell Fusion and Heterokaryon Formation in Filamentous Fungi.

    Science.gov (United States)

    Daskalov, Asen; Heller, Jens; Herzog, Stephanie; Fleißner, André; Glass, N Louise

    2017-03-01

    For the majority of fungal species, the somatic body of an individual is a network of interconnected cells sharing a common cytoplasm and organelles. This syncytial organization contributes to an efficient distribution of resources, energy, and biochemical signals. Cell fusion is a fundamental process for fungal development, colony establishment, and habitat exploitation and can occur between hyphal cells of an individual colony or between colonies of genetically distinct individuals. One outcome of cell fusion is the establishment of a stable heterokaryon, culminating in benefits for each individual via shared resources or being of critical importance for the sexual or parasexual cycle of many fungal species. However, a second outcome of cell fusion between genetically distinct strains is formation of unstable heterokaryons and the induction of a programmed cell death reaction in the heterokaryotic cells. This reaction of nonself rejection, which is termed heterokaryon (or vegetative) incompatibility, is widespread in the fungal kingdom and acts as a defense mechanism against genome exploitation and mycoparasitism. Here, we review the currently identified molecular players involved in the process of somatic cell fusion and its regulation in filamentous fungi. Thereafter, we summarize the knowledge of the molecular determinants and mechanism of heterokaryon incompatibility and place this phenomenon in the broader context of biotropic interactions and immunity.

  12. Granulocyte colony-stimulating factor mobilizes dormant hematopoietic stem cells without proliferation in mice.

    Science.gov (United States)

    Bernitz, Jeffrey M; Daniel, Michael G; Fstkchyan, Yesai S; Moore, Kateri

    2017-04-06

    Granulocyte colony-stimulating factor (G-CSF) is used clinically to treat leukopenia and to enforce hematopoietic stem cell (HSC) mobilization to the peripheral blood (PB). However, G-CSF is also produced in response to infection, and excessive exposure reduces HSC repopulation capacity. Previous work has shown that dormant HSCs contain all the long-term repopulation potential in the bone marrow (BM), and that as HSCs accumulate a divisional history, they progressively lose regenerative potential. As G-CSF treatment also induces HSC proliferation, we sought to examine whether G-CSF-mediated repopulation defects are a result of increased proliferative history. To do so, we used an established H2BGFP label retaining system to track HSC divisions in response to G-CSF. Our results show that dormant HSCs are preferentially mobilized to the PB on G-CSF treatment. We find that this mobilization does not result in H2BGFP label dilution of dormant HSCs, suggesting that G-CSF does not stimulate dormant HSC proliferation. Instead, we find that proliferation within the HSC compartment is restricted to CD41-expressing cells that function with short-term, and primarily myeloid, regenerative potential. Finally, we show CD41 expression is up-regulated within the BM HSC compartment in response to G-CSF treatment. This emergent CD41 Hi HSC fraction demonstrates no observable engraftment potential, but directly matures into megakaryocytes when placed in culture. Together, our results demonstrate that dormant HSCs mobilize in response to G-CSF treatment without dividing, and that G-CSF-mediated proliferation is restricted to cells with limited regenerative potential found within the HSC compartment. © 2017 by The American Society of Hematology.

  13. Tuning and elucidation of the colony dimorphism in Rhodococcus ruber associated with cell flocculation in large scale fermentation.

    Science.gov (United States)

    Jiao, Song; Chen, Jie; Yu, Huimin; Shen, Zhongyao

    2017-08-01

    Prevention of cell flocculation in large-scale fermentation is of great importance for most industrial microbes. Using Rhodococcus ruber TH3 as a model strain, we revealed that the undesired cell flocculation in a fermenter was associated with the colony dimorphism phenomenon, and it only occurred in the rough-type of cells (R-TH3) instead of the smooth-type of cells (S-TH3). By analyzing the transcriptome differences of R-TH3 and S-TH3, six representative genes with significantly upregulated transcription in S-TH3 were selected and overexpressed in R-TH3. The colony morphotypes of the six engineered strains changed to different extents, in which overexpressions of three lipid metabolism-related proteins LM1, LM2, and LM3 tuned the colony morphotype from rough to almost as smooth as in S-TH3. SEM observation confirmed the cell surface difference of the engineered strains from R-TH3. Their cell surface hydrophobicity also reduced, and the cell sedimentation behaviors were consequently changed as expected. Using R-TH3/LM1 as the representative of the engineered bacteria, fatty acids of the cell envelopes were measured. Fatty acid contents of S-TH3, R-TH3/LM1, and R-TH3 were 27.21, 24.10, and 22.24%, respectively. Among all the fatty acids, stearic acid binding to hydrophilic extracellular polysaccharides (EPS) in Rhodococcus showed significant differences among the cells. The EPS contents of S-TH3, R-TH3/LM1, and R-TH3 were 191, 163, and 137 mg/g cells. Hence, the hydrophilicity of the S-TH3 cells was mainly due to the EPS in the outermost layer of the cells. Increase of fatty acids especially stearic acid results in the increase of the bound EPS, finally bringing about the hydrophilicity enhancement.

  14. Tritiated thymidine and deoxycytidine suicide of mouse hemopoietic colony forming cells (CFC)

    International Nuclear Information System (INIS)

    Uyeki, E.M.; Wierzba, K.; Bisel, T.U.

    1981-01-01

    Significant enhancement of tritiated dCyd suicide occurred when unlabelled dThd was added to cultures of mouse monocytic colony-forming cells. Incorporation experiments supported the suicide experiments in that incorporation of tritiated dCyd into DNA was significantly increased. One hundred micromolar dCyd significantly reduced the radiotoxicity of 0.3 μCi of tritiated dThd; incorporation experiments indicated a dose-related reduction in the incorporation of tritiated dThd into DNA with the addition of 1-100 μM unlabelled dCyd. The addition of 1 μM aminopterin reversed the effect of 100 μM deoxycytidine; viz., incorporation of dThd into DNA was 90% of controls. Aminopterin had a similar effect on deoxyuridine reversal of tritiated dThd incorporation into DNA. Aminopterin had no effect on the reduction of tritiated dThd incorporation into DNA due to the addition of 100 μM unlabelled thymidine. Unlabelled ribonucleosides, Urd and Cyd, did not significantly affect the suicide pattern of tritiated dThd or dCyd when they were added to CFC cultures. Unlabelled deoxyribonucleosides, dThd or dCyd, did not significantly affect the suicide pattern of either tritiated Cyd or Urd when they were added to cultures containing tritiated ribonucleosides. Unlabelled Urd or Cyd was effective in reversing the suicide due to tritiated Urd or Cyd. (author)

  15. A simple mathematical model that describes the growth of the area and the number of total and viable cells in yeast colonies.

    Science.gov (United States)

    Rivas, E-M; Gil de Prado, E; Wrent, P; de Silóniz, M-I; Barreiro, P; Correa, E C; Conejero, F; Murciano, A; Peinado, J M

    2014-12-01

    We propose a model, based on the Gompertz equation, to describe the growth of yeasts colonies on agar medium. This model presents several advantages: (i) one equation describes the colony growth, which previously needed two separate ones (linear increase of radius and of the squared radius); (ii) a similar equation can be applied to total and viable cells, colony area or colony radius, because the number of total cells in mature colonies is proportional to their area; and (iii) its parameters estimate the cell yield, the cell concentration that triggers growth limitation and the effect of this limitation on the specific growth rate. To elaborate the model, area, total and viable cells of 600 colonies of Saccharomyces cerevisiae, Debaryomyces fabryi, Zygosaccharomyces rouxii and Rhodotorula glutinis have been measured. With low inocula, viable cells showed an initial short exponential phase when colonies were not visible. This phase was shortened with higher inocula. In visible or mature colonies, cell growth displayed Gompertz-type kinetics. It was concluded that the cells growth in colonies is similar to liquid cultures only during the first hours, the rest of the time they grow, with near-zero specific growth rates, at least for 3 weeks. Mathematical models used to predict microbial growth are based on liquid cultures data. Models describing growth on solid surfaces, highlighting the differences with liquids cultures, are scarce. In this work, we have demonstrated that a single Gompertz equation describes accurately the increase of the yeast colonies, up to the point where they reach their maximum size. The model can be used to quantify the differences in growth kinetics between solid and liquid media. Moreover, as all its parameters have biological meaning, it could be used to build secondary models predicting yeast growth on solid surfaces under several environmental conditions. © 2014 The Society for Applied Microbiology.

  16. Natural factors and antropics and their relationship with the density of colonies of Melipona beecheii in five vegetable formations of the valley San Andres

    Directory of Open Access Journals (Sweden)

    Katiuska Ravelo Pimentel

    2014-12-01

    Full Text Available It is evaluated the influence of natural factors and antropics on the density of colonies of Melipona beecheii in forest five vegetable formations of the solid one of the valley San Andrés, through surveys to residents and workers of the area, as well as the observations and samplings carried out in the studied vegetable formations. The following factors were studied: rocosity, vegetable covering, flourished plants, height of the entrance hole and the man's activity; being determined that the density of beehives has been affected fundamentally by factors antropics, having this its biggest incidence in the gallery forests, being this the most affected one. The pruning of trees, the naturalness of the forests and their access affect the population's conservation considerably under natural conditions, what demonstrates that this it is the main factor that locates in extirpation danger to the species in the study area. In turn the density of colonies keeps direct relationship with the other analyzed factors, since the same ones depend on the trees for the location of its nests, of the time in that the plants flourish for its feeding and of the holes found in the rocks, so much for the making of its colonies like it stops its establishment and reproduction.

  17. Recombinant human granulocyte colony-stimulating factor increases circulating CD34-postive cells in patients with AIDS

    DEFF Research Database (Denmark)

    Nielsen, S D; Dam-Larsen, S; Nielsen, C

    1997-01-01

    In a gene therapy-based treatment of AIDS, it would be desirable to have as many transduced target cells as possible. A limiting factor is the number of target cells. In this study, we investigated whether it was possible to increase the absolute number of one possible target cell, i.......e., the circulating hematopoietic progenitor cells (CD34 cells) in patients with AIDS, using the recombinant human granulocyte colony-stimulating factor (G-CSF). Eight patients with AIDS were treated with G-CSF for neutropenia (... cells. The median increase in CD34 cells was from 0.8 to 2.2 x 10(6)/l. Finally, using a highly sensitive HIV-1 RNA PCR, we found that treatment of AIDS patients with G-CSF did not lead to enhanced HIV replication. These observations indicate that G-CSF may be used to mobilize CD34 cells in patients...

  18. Differential colony size, cell length, and cellular proteome of Escherichia coli isolated from urine vs. stone nidus of kidney stone patients.

    Science.gov (United States)

    Tavichakorntrakool, Ratree; Boonsiri, Patcharee; Prasongwatana, Vitoon; Lulitanond, Aroonlug; Wongkham, Chaisiri; Thongboonkerd, Visith

    2017-03-01

    Escherichia coli is associated with kidney stone disease, as a cause or an effect (secondary or recurrent urinary tract infection, UTI). Defining phenotypic or functional differences between E. coli inside stone nidus (ECS, associated with infection-induced stone) and outside the stone (i.e. from urine) (ECU, represented secondary infection) would be helpful to better understand bacterial involvement in this disease. ECS and ECU were isolated from 100 stone formers and subjected to antimicrobial susceptibility test, ERIC-PCR genotyping, determination of biofilm formation, bacterial colony size on agar plate and cell length in broth, 2-DE, nanoLC-MS/MS, protein network analysis, and pyruvate dehydrogenase (PDH) activity assay. From 100 stone formers, 36 had positive bacterial culture, of which 5 pairs had identical antimicrobial susceptibility patterns and comparable ERIC-PCR genotypes. ECS had smaller colony size and longer cell length than ECU. 2-DE proteomic analysis revealed significantly differential levels of proteins involved in carbohydrate metabolism, stress response, and RNA/protein metabolism. Functional validation demonstrated lower PDH activity in ECS. All these differential phenotypic and cellular proteome findings might be adaptive response of E. coli from remote infection to survive within the stone matrix that subsequently caused recurrent UTI in kidney stone patients. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. REVENUE FARMING AND IMPERIAL TRANSITION: AN ECONOMIC DIMENSION OF EARLY COLONIAL STATE FORMATION IN JAVA, C. 1800s-1820s

    Directory of Open Access Journals (Sweden)

    Abdul Wahid

    2012-11-01

    Full Text Available Revenue farming (pacht or verpachtingen in Dutch is a fiscal institution that existed in Java since the pre-colonial period. During the VOC period, the Dutch modified, institutionalized and &extended it as one of their fiscal institutions to solve human resource shortage and administrative barriers in collecting taxes from local population. For political and economic reasons the Dutch favored the Chinese as main partners in operating the system. The system was proven efficient to an extent that it collected substantial revenue contribution to the state exchequer. During the period of 'imperial'  transition from 1800s until 1820s, changing regimes in Java retained the system to finance their political agenda. This paper argues that revenue-farming system was the financial source for the Dutch in establishing a real colonial state in Java.

  20. Bacterial lipopolysaccharide induces osteoclast formation in RAW 264.7 macrophage cells

    International Nuclear Information System (INIS)

    Islam, Shamima; Hassan, Ferdaus; Tumurkhuu, Gantsetseg; Dagvadorj, Jargalsaikhan; Koide, Naoki; Naiki, Yoshikazu; Mori, Isamu; Yoshida, Tomoaki; Yokochi, Takashi

    2007-01-01

    Lipopolysaccharide (LPS) is a potent bone resorbing factor. The effect of LPS on osteoclast formation was examined by using murine RAW 264.7 macrophage cells. LPS-induced the formation of multinucleated giant cells (MGC) in RAW 264.7 cells 3 days after the exposure. MGCs were positive for tartrate-resistant acid phosphatase (TRAP) activity. Further, MGC formed resorption pits on calcium-phosphate thin film that is a substrate for osteoclasts. Therefore, LPS was suggested to induce osteoclast formation in RAW 264.7 cells. LPS-induced osteoclast formation was abolished by anti-tumor necrosis factor (TNF)-α antibody, but not antibodies to macrophage-colony stimulating factor (M-CSF) and receptor activator of nuclear factor (NF)-κB ligand (RANKL). TNF-α might play a critical role in LPS-induced osteoclast formation in RAW 264.7 cells. Inhibitors of NF-κB and stress activated protein kinase (SAPK/JNK) prevented the LPS-induced osteoclast formation. The detailed mechanism of LPS-induced osteoclast formation is discussed

  1. Colony formation of C57BL/6J mice in visible burrow system: identification of eusocial behaviors in a background strain for genetic animal models of autism.

    Science.gov (United States)

    Arakawa, Hiroyuki; Blanchard, D Caroline; Blanchard, Robert J

    2007-01-10

    Deficits in social interaction are primary characteristics of autism, which has strong genetic components. Genetically manipulated mouse models may provide a useful research tool to advance the investigation of genes associated with autism. To identify these genes using mouse models, behavioral assays for social relationships in the background strains must be developed. The present study examined colony formation in groups of one male and three female mice (Experiment 1) and, groups of three male mice (Experiment 2) of the C57BL/6J strain in a semi-natural visible burrow system. For adult mixed-sex colonies, 4-h observations during both the dark and light cycles for 15 days demonstrated day-dependent increases in huddling together in the chamber accompanied by decreased frequencies of active social behaviors. Sequential analyses of social interactions indicated that approaches to the back of the approached animal typically elicited flight, while approaches to the front of the approached animal failed to do so. This was seen for female to female, and for female to male approaches, as well as male to female approaches, strongly counterindicating a view that rear approach/flight specifically reflects female responsivirity to unwanted male sexual approach. For adult male colonies, similar protocols found that these social behaviors were similar to those of adult mixed-sex colonies. These findings suggest two potentially useful measures of eusocial behavior in mice, of possible value for genetic mouse models of autism; that is, huddling together and approaches to the front but not the back, of conspecifics.

  2. Growth of human T lymphocyte colonies from whole blood: culture requirements and applications

    International Nuclear Information System (INIS)

    Knox, S.J.; Wilson, F.D.; Greenberg, B.R.; Shifrine, M.

    1982-01-01

    Growth of human lymphocyte colonies from whole blood following stimulation with PHA, Con A, or PPD is described. Individual colony cells were identified as T lymphocytes on the basis of surface marker and enzyme cytochemical characterizations. Colony formation increased as a power function over a wide range of cell concentrations above a critical minimal concentration. The whole blood culture system eliminates possible selective effects of lymphocyte colony techniques utilizing gradient-enriched lymphocyte fractions and more closely approximates the in vivo milieu. The whole blood colony method is more sensitive for the detection of low-level radiation effects on lymphocytes than widely used tests that measure 3 H-thymidine incorporation. In preliminary studies, researchers used the whole blood method to determine the relative radiosensitivity of lymphocytes from humans with various hematopoietic disorders, and observed abnormalities in mitogen responsiveness and colony formation in some of the patient groups. This method has wide application for studies in cellular and clinical immunology

  3. The Transcription Factor Nrf2 Protects Angiogenic Capacity of Endothelial Colony-Forming Cells in High-Oxygen Radical Stress Conditions

    Directory of Open Access Journals (Sweden)

    Hendrik Gremmels

    2017-01-01

    Full Text Available Background. Endothelial colony forming cells (ECFCs have shown a promise in tissue engineering of vascular constructs, where they act as endothelial progenitor cells. After implantation, ECFCs are likely to be subjected to elevated reactive oxygen species (ROS. The transcription factor Nrf2 regulates the expression of antioxidant enzymes in response to ROS. Methods. Stable knockdown of Nrf2 and Keap1 was achieved by transduction with lentiviral shRNAs; activation of Nrf2 was induced by incubation with sulforaphane (SFN. Expression of Nrf2 target genes was assessed by qPCR, oxidative stress was assessed using CM-DCFDA, and angiogenesis was quantified by scratch-wound and tubule-formation assays. Results. Nrf2 knockdown led to a reduction of antioxidant gene expression and increased ROS. Angiogenesis was disturbed after Nrf2 knockdown even in the absence of ROS. Conversely, angiogenesis was preserved in high ROS conditions after knockdown of Keap1. Preincubation of ECFCs with SFN reduced intracellular ROS in the presence of H2O2 and preserved scratch-wound closure and tubule-formation. Conclusion. The results of this study indicate that Nrf2 plays an important role in the angiogenic capacity of ECFCs, particularly under conditions of increased oxidative stress. Pretreatment of ECFCs with SFN prior to implantation may be a protective strategy for tissue-engineered constructs or cell therapies.

  4. Differential effect of chlorine on the oxidative stress generation in dormant and active cells within colony biofilm.

    Science.gov (United States)

    Kim, Jaeeun; Park, Hee-Jin; Lee, Joon-Hee; Hahn, Ji-Sook; Gu, Man Bock; Yoon, Jeyong

    2009-12-01

    In an effort to better control bacterial biofilm, we examined the effects of various oxidative antimicrobial chemicals including silver, paraquat, hydrogen peroxide, and chlorine depending on the physiological status of cells in biofilm. The metabolically heterogeneous cells within colony biofilm were physically fractionated and the oxidative stress generated in each fraction was monitored by soxS and oxyS promoter reporter systems. Chlorine induced soxS to a greater degree in the dormant cells than active cells of biofilm. In addition, chlorine-dependent induction of soxS was more prominent in aerobically grown cells compared with anaerobically grown cells. On the contrary, the soxS induction by other chemicals such as paraquat and silver, and the oxyS induction by hydrogen peroxide were higher in active biofilm cells and aerobically grown cells. Our results suggest that chlorine might generate strong oxidative stress by direct modification of the 2Fe-2S cluster in an O(2)-independent manner, which provides the molecular basis of our previous report showing that chlorine has a more efficient killing effect on dormant cells in biofilm and cells grown under unaerobic conditions. This study shows that chlorine may be particularly promising for the control of anaerobic bacteria and biofilm where dormant cells are hard to control.

  5. The co-injection of somatic cells with embryonic stem cells affects teratoma formation and the properties of teratoma-derived stem cell-like cells.

    Directory of Open Access Journals (Sweden)

    Seung Pyo Gong

    Full Text Available The aim of this study was to assess the biological reactions triggered by stem cell transplantation related to phenotypic alteration, host-to-cell response, chromosomal stability, transcriptional alteration, and stem cell-like cell re-expansion. B6CBAF1 mouse embryonic stem cells (ESCs were injected subcutaneously into homologous or heterologous (B6D2F1 recipients, and heterologous injections were performed with or without co-injection of B6D2F1 fetal fibroblasts. All homologous injections resulted in teratoma formation, whereas a sharp decrease in formation was detected after heterologous injection (100 vs. 14%; p<0.05. The co-injection of somatic cells in heterologous injections enhanced teratoma formation significantly (14 vs. 75%; p<0.05. Next, ESC-like cell colonies with the same genotype as parental ESCs were formed by culturing teratoma-dissociated cells. Compared with parental ESCs, teratoma-derived ESC-like cells exhibited significantly increased aneuploidy, regardless of homologous or heterologous injections. Repopulation of the parental ESCs was the main factor that induced chromosomal instability, whereas the co-injection of somatic cells did not restore chromosomal normality. Different genes were expressed in the parental ESCs and teratoma-derived ESC-like cells; the difference was larger with parental vs. heterologous than parental vs. homologous co-injections. The co-injection of somatic cells decreased this difference further. In conclusion, the host-to-cell interactions triggered by ESC transplantation could be modulated by co-injection with somatic cells. A mouse model using homologous or heterologous transplantation of stem cells could help monitor cell adaptability and gene expression after injection.

  6. Increase in colony-forming efficiency in soft agar of thymus cells from radiation-induced thymomas of NIH Swiss mice

    International Nuclear Information System (INIS)

    Mori, Nobuko; Takamori, Yasuhiko; Hori, Yasuharu

    1982-01-01

    Colony-forming efficiency in soft agar of radiation-induced thymoma in NIH Swiss mice was determined in the presence of cultured medium of reticulo-epitherial cells from normal thymus of NIH Swiss mouse as conditioned medium. A similar experiment was done with thymomas spontaneousely developed in AKR mice. Most of colonies developed in soft agar were not composed of thymic lymphoma cells, but of macrophage-like cells. The ratio of the number of colonies to that of the seeded cells significantly increased in thymomas comparing with that in normal thymus. This result corresponded with the increased number of macrophages in thymoma, as determined by counting phagocytic cells of adherent cells. (author)

  7. Macrophage Colony Stimulating Factor Derived from CD4+ T Cells Contributes to Control of a Blood-Borne Infection.

    Science.gov (United States)

    Fontana, Mary F; de Melo, Gabrielly L; Anidi, Chioma; Hamburger, Rebecca; Kim, Chris Y; Lee, So Youn; Pham, Jennifer; Kim, Charles C

    2016-12-01

    Dynamic regulation of leukocyte population size and activation state is crucial for an effective immune response. In malaria, Plasmodium parasites elicit robust host expansion of macrophages and monocytes, but the underlying mechanisms remain unclear. Here we show that myeloid expansion during P. chabaudi infection is dependent upon both CD4+ T cells and the cytokine Macrophage Colony Stimulating Factor (MCSF). Single-cell RNA-Seq analysis on antigen-experienced T cells revealed robust expression of Csf1, the gene encoding MCSF, in a sub-population of CD4+ T cells with distinct transcriptional and surface phenotypes. Selective deletion of Csf1 in CD4+ cells during P. chabaudi infection diminished proliferation and activation of certain myeloid subsets, most notably lymph node-resident CD169+ macrophages, and resulted in increased parasite burden and impaired recovery of infected mice. Depletion of CD169+ macrophages during infection also led to increased parasitemia and significant host mortality, confirming a previously unappreciated role for these cells in control of P. chabaudi. This work establishes the CD4+ T cell as a physiologically relevant source of MCSF in vivo; probes the complexity of the CD4+ T cell response during type 1 infection; and delineates a novel mechanism by which T helper cells regulate myeloid cells to limit growth of a blood-borne intracellular pathogen.

  8. Collagen-IV supported embryoid bodies formation and differentiation from buffalo (Bubalus bubalis) embryonic stem cells

    Energy Technology Data Exchange (ETDEWEB)

    Taru Sharma, G., E-mail: gts553@gmail.com [Reproductive Physiology Laboratory, Division of Physiology and Climatology, Indian Veterinary Research Institute, Izatnagar-243 122, Bareilly, U.P. (India); Dubey, Pawan K.; Verma, Om Prakash; Pratheesh, M.D.; Nath, Amar; Sai Kumar, G. [Reproductive Physiology Laboratory, Division of Physiology and Climatology, Indian Veterinary Research Institute, Izatnagar-243 122, Bareilly, U.P. (India)

    2012-08-03

    Graphical abstract: EBs formation, characterization and expression of germinal layers marker genes of in vivo developed teratoma using four different types of extracellular matrices. Highlights: Black-Right-Pointing-Pointer Collagen-IV matrix is found cytocompatible for EBs formation and differentiation. Black-Right-Pointing-Pointer Established 3D microenvironment for ES cells development and differentiation into three germ layers. Black-Right-Pointing-Pointer Collagen-IV may be useful as promising candidate for ES cells based therapeutic applications. -- Abstract: Embryoid bodies (EBs) are used as in vitro model to study early extraembryonic tissue formation and differentiation. In this study, a novel method using three dimensional extracellular matrices for in vitro generation of EBs from buffalo embryonic stem (ES) cells and its differentiation potential by teratoma formation was successfully established. In vitro derived inner cell masses (ICMs) of hatched buffalo blastocyst were cultured on buffalo fetal fibroblast feeder layer for primary cell colony formation. For generation of EBs, pluripotent ES cells were seeded onto four different types of extracellular matrices viz; collagen-IV, laminin, fibronectin and matrigel using undifferentiating ES cell culture medium. After 5 days of culture, ESCs gradually grew into aggregates and formed simple EBs having circular structures. Twenty-six days later, they formed cystic EBs over collagen matrix with higher EBs formation and greater proliferation rate as compared to other extracellular matrices. Studies involving histological observations, fluorescence microscopy and RT-PCR analysis of the in vivo developed teratoma revealed that presence of all the three germ layer derivatives viz. ectoderm (NCAM), mesoderm (Flk-1) and endoderm (AFP). In conclusion, the method described here demonstrates a simple and cost-effective way of generating EBs from buffalo ES cells. Collagen-IV matrix was found cytocompatible as it

  9. OpenCFU, a new free and open-source software to count cell colonies and other circular objects.

    Science.gov (United States)

    Geissmann, Quentin

    2013-01-01

    Counting circular objects such as cell colonies is an important source of information for biologists. Although this task is often time-consuming and subjective, it is still predominantly performed manually. The aim of the present work is to provide a new tool to enumerate circular objects from digital pictures and video streams. Here, I demonstrate that the created program, OpenCFU, is very robust, accurate and fast. In addition, it provides control over the processing parameters and is implemented in an intuitive and modern interface. OpenCFU is a cross-platform and open-source software freely available at http://opencfu.sourceforge.net.

  10. Colonial Institutions

    DEFF Research Database (Denmark)

    McAtackney, Laura; Palmer, Russell

    2016-01-01

    Archaeologically based explorations of colonialism or institutions are common case-studies in global historical archaeology, but the “colonial institution”—the role of institutions as operatives of colonialism—has often been neglected. In this thematic edition we argue that in order to fully...... understand the interconnected, global world one must explicitly dissect the colonial institution as an entwined, dual manifestation that is central to understanding both power and power relations in the modern world. Following Ann Laura Stoler, we have selected case studies from the Australia, Europe, UK...... and the USA which reveal that the study of colonial institutions should not be limited to the functional life of these institutions—or solely those that take the form of monumental architecture—but should include the long shadow of “imperial debris” (Stoler 2008) and immaterial institutions....

  11. Bone marrow and tumor cell colony-forming units and human tumor xenograft efficacy of noncamptothecin and camptothecin topoisomerase I inhibitors.

    Science.gov (United States)

    Kurtzberg, Leslie S; Battle, Traci; Rouleau, Cecile; Bagley, Rebecca G; Agata, Naoki; Yao, Min; Schmid, Steven; Roth, Stephanie; Crawford, Jennifer; Krumbholz, Roy; Ewesuedo, Reginald; Yu, Xian-Jie; Wang, Fei; Lavoie, Edmond J; Teicher, Beverly A

    2008-10-01

    Topoisomerase I (TopoI), an established anticancer target, is an enzyme producing a single-strand DNA break during transcription. Several noncamptothecin TopoI inhibitors have been identified. One of these, ARC-111, was compared with two clinically used camptothecins, topotecan and irinotecan/SN-38. In mouse and human bone marrow colony formation [colony-forming units granulocyte-macrophage (CFU-GM)] assays, the IC(90) values were 519 and 331 nmol/L for topotecan and SN-38 mouse CFU-GM and were 19 and 26 nmol/L for human CFU-GM, giving mouse to human differentials of 28- and 13-fold. ARC-111 produced IC(90) values of 28 nmol/L in mouse and 6.2 nmol/L in human CFU-GM, thus only a 4.5-fold differential between species. Human bone marrow CFU-GM was more sensitive to topotecan than were several human cancer cell lines, but ARC-111 cytotoxicity was similar for human bone marrow CFU-GM and the seven human tumor cell lines tested. In HCT-116 xenografts, tumor growth delays (TGD) were 17 days for irinotecan and 20 days for ARC-111. In HT-29 xenografts, the TGD was 9 days for both irinotecan and ARC-111. Both ARC-111 and docetaxel had a TGD of 21 days in NCI-H460 xenografts, and both ARC-111 and gemcitabine had a TGD of 7 days in MiaPaCa2 xenograft. Current TopoI inhibitors have broad antitumor activity in human tumor xenografts that is not achieved in the clinic. This may be due to greater sensitivity of human bone marrow than mouse to the cytotoxicity of these agents. It may be possible to achieve similar levels of ARC-111 in patients as in mice allowing improved antitumor activity.

  12. Radiosensitivity of kidney colony-forming cells: a short-term assay in situ in the mouse

    International Nuclear Information System (INIS)

    Ewen, C.; Hendry, J.H.

    1989-01-01

    A short-term colony assay for renal tubule epithelium has been developed. Uranyl nitrate (UN) is a heavy metal nephrotoxin that induces acute tubule necrosis followed by a large compensatory increase in the rate of cell proliferation in the nephron. UN was used to precipitate latent damage following renal irradiation. Using a subcapsular colony count at 14 days after unilateral irradiation, a single-dose cell survival curve was obtained with a D0 of 4.2 +/- 0.3 Gy. High-dose irradiation of an exteriorized kidney resulted in a survival curve which was biphasic, with a plateau in survival between 18 and 40 Gy. Subtraction of this plateau level from all the survival data gave D0 values of 2.5 +/- 0.2 Gy (data analyzed between 7.5 and 16 Gy) or 2.0 +/- 0.2 Gy (over range 12-16 Gy). The D0 value obtained at 20 months after bilateral (or unilateral) kidney irradiation, without the use of UN, was 2.9 +/- 1.1 Gy (over range 10-14 Gy)

  13. Pre-B cell colony enhancing factor/NAMPT/visfatin and its role in inflammation-related bone disease

    Energy Technology Data Exchange (ETDEWEB)

    Moschen, Alexander R.; Geiger, Sabine; Gerner, Romana [Christian Doppler Research Laboratory for Gut Inflammation and Department of Internal Medicine II (Gastroenterology and Hepatology), Innsbruck Medical University, Anichstrasse 35, 6020 Innsbruck (Austria); Tilg, Herbert, E-mail: herbert.tilg@i-med.ac.at [Christian Doppler Research Laboratory for Gut Inflammation and Department of Internal Medicine II (Gastroenterology and Hepatology), Innsbruck Medical University, Anichstrasse 35, 6020 Innsbruck (Austria)

    2010-08-07

    Chronic inflammation affects bone metabolism and is commonly associated with the presence of osteoporosis. Bone loss is directed by various immune mediators such as the pro-inflammatory cytokines tumour necrosis factor-alpha, interleukin 1-beta or interferon-gamma. Pre-B cell colony enhancing factor (PBEF)/nicotinamide phosphoribosyl transferase (NAMPT)/visfatin is a pleiotropic mediator acting as growth factor, cytokine and enzyme involved in energy and nicotinamide adenine dinucleotide (NAD) metabolism. PBEF/NAMPT/visfatin has been recently demonstrated to exert several pro-inflammatory functions. We studied serum levels of PBEF/NAMPT/visfatin in patients with inflammatory bowel diseases (IBD) and their relation with bone mineral density (BMD). Furthermore, we were interested whether PBEF/NAMPT/visfatin affects osteoclastogenesis and involved mediators. PBEF/NAMPT/visfatin serum levels were increased in patients with IBD, correlated positively with disease activity and negatively with BMD, especially in the lumbar spine. Osteoclast precursor cells were generated from peripheral blood mononuclear cells after stimulation with various growth factors such as macrophage colony-stimulating factor (M-CSF) and soluble ligand of receptor activator of nuclear factor kappa B (RANK). In these in vitro studies, PBEF/NAMPT/visfatin suppressed osteoclastogenesis and inhibited the differentiation of osteoclast precursors into tartrate-resistant acid phosphatase positive multinucleated cells. These effects were paralleled by the suppression of the osteoclast typical markers RANK, nuclear factor of activated T-cells c1 (NFATc1) and cathepsin-K. This is the first report demonstrating a potential role for this important cytokine/enzyme in inflammation-related bone disease.

  14. Pre-B cell colony enhancing factor/NAMPT/visfatin and its role in inflammation-related bone disease

    International Nuclear Information System (INIS)

    Moschen, Alexander R.; Geiger, Sabine; Gerner, Romana; Tilg, Herbert

    2010-01-01

    Chronic inflammation affects bone metabolism and is commonly associated with the presence of osteoporosis. Bone loss is directed by various immune mediators such as the pro-inflammatory cytokines tumour necrosis factor-alpha, interleukin 1-beta or interferon-gamma. Pre-B cell colony enhancing factor (PBEF)/nicotinamide phosphoribosyl transferase (NAMPT)/visfatin is a pleiotropic mediator acting as growth factor, cytokine and enzyme involved in energy and nicotinamide adenine dinucleotide (NAD) metabolism. PBEF/NAMPT/visfatin has been recently demonstrated to exert several pro-inflammatory functions. We studied serum levels of PBEF/NAMPT/visfatin in patients with inflammatory bowel diseases (IBD) and their relation with bone mineral density (BMD). Furthermore, we were interested whether PBEF/NAMPT/visfatin affects osteoclastogenesis and involved mediators. PBEF/NAMPT/visfatin serum levels were increased in patients with IBD, correlated positively with disease activity and negatively with BMD, especially in the lumbar spine. Osteoclast precursor cells were generated from peripheral blood mononuclear cells after stimulation with various growth factors such as macrophage colony-stimulating factor (M-CSF) and soluble ligand of receptor activator of nuclear factor kappa B (RANK). In these in vitro studies, PBEF/NAMPT/visfatin suppressed osteoclastogenesis and inhibited the differentiation of osteoclast precursors into tartrate-resistant acid phosphatase positive multinucleated cells. These effects were paralleled by the suppression of the osteoclast typical markers RANK, nuclear factor of activated T-cells c1 (NFATc1) and cathepsin-K. This is the first report demonstrating a potential role for this important cytokine/enzyme in inflammation-related bone disease.

  15. Formative cell divisions: principal determinants of plant morphogenesis.

    Science.gov (United States)

    Smolarkiewicz, Michalina; Dhonukshe, Pankaj

    2013-03-01

    Formative cell divisions utilizing precise rotations of cell division planes generate and spatially place asymmetric daughters to produce different cell layers. Therefore, by shaping tissues and organs, formative cell divisions dictate multicellular morphogenesis. In animal formative cell divisions, the orientation of the mitotic spindle and cell division planes relies on intrinsic and extrinsic cortical polarity cues. Plants lack known key players from animals, and cell division planes are determined prior to the mitotic spindle stage. Therefore, it appears that plants have evolved specialized mechanisms to execute formative cell divisions. Despite their profound influence on plant architecture, molecular players and cellular mechanisms regulating formative divisions in plants are not well understood. This is because formative cell divisions in plants have been difficult to track owing to their submerged positions and imprecise timings of occurrence. However, by identifying a spatiotemporally inducible cell division plane switch system applicable for advanced microscopy techniques, recent studies have begun to uncover molecular modules and mechanisms for formative cell divisions. The identified molecular modules comprise developmentally triggered transcriptional cascades feeding onto microtubule regulators that now allow dissection of the hierarchy of the events at better spatiotemporal resolutions. Here, we survey the current advances in understanding of formative cell divisions in plants in the context of embryogenesis, stem cell functionality and post-embryonic organ formation.

  16. Contact formation in gallium arsenide solar cells

    Science.gov (United States)

    Weizer, Victor G.; Fatemi, Navid S.

    1988-01-01

    Gold and gold-based alloys, commonly used as solar cell contact materials, are known to react readily with gallium arsenide. Experiments were performed to identify the mechanisms involved in these GaAs-metal interactions. It is shown that the reaction of GaAs with gold takes place via a dissociative diffusion process. It is shown further that the GaAs-metal reaction rate is controlled to a very great extent by the condition of the free surface of the contact metal, an interesting example of which is the previously unexplained increase in the reaction rate that has been observed for samples annealed in a vacuum environment as compared to those annealed in a gaseous ambient. A number of other hard-to-explain observations, such as the low-temperature formation of voids in the gold lattice and crystallite growth on the gold surface, are explained by invoking this mechanism.

  17. Clinical use of plerixafor in combination with granulocyte-colony stimulating factor in hematopoietic stem cell transplantation

    Directory of Open Access Journals (Sweden)

    Cedar J Fowler

    2010-05-01

    Full Text Available Cedar J Fowler1, Richard T Maziarz21Laboratory of Clinical Infectious Diseases – NIAID, National Institutes of Health, Bethesda, MD, USA; 2Adult Blood and Marrow Stem Cell Transplant Program, Oregon Health and Science University, Portland, OR, USAAbstract: Plerixafor is a CXC4:CXCL12 antagonist that has an expanding role in the stem cell mobilization phase of the hematopoietic stem cell transplant procedure. The drug is currently licensed by the FDA to be used in combination with granulocyte colony stimulating factor (G-CSF to mobilize hematopoietic stem cells into the peripheral blood for collection and subsequent autologous transplantations in patients with non-Hodgkin’s lymphoma and multiple myeloma. Plerixafor is particularly useful in patients who have been heavily pretreated or as effective therapy for frontline salvage of poor peripheral blood stem cells mobilizers. In conjunction with G-CSF, plerixafor can be successful in decreasing the number of apheresis days and therefore the associated additional risks and cost of more apheresis procedures. Patients taking plerixafor, when compared to the side effect profile of G-CSF alone, do not report significantly more side effects.Keywords: plerixafor, AMD3100, autologous stem cell mobilization, non-Hodgkin’s lymphoma, multiple myeloma, CXCR4, CXCL12

  18. The Transcription Factor Nrf2 Protects Angiogenic Capacity of Endothelial Colony-Forming Cells in High-Oxygen Radical Stress Conditions

    NARCIS (Netherlands)

    Gremmels, Hendrik; De Jong, Olivier G.; Hazenbrink, Diënty H.; Fledderus, Joost O.; Verhaar, Marianne C.

    2017-01-01

    Background. Endothelial colony forming cells (ECFCs) have shown a promise in tissue engineering of vascular constructs, where they act as endothelial progenitor cells. After implantation, ECFCs are likely to be subjected to elevated reactive oxygen species (ROS). The transcription factor Nrf2

  19. Optimization of the culturing conditions of human umbilical cord blood-derived endothelial colony-forming cells under xeno-free conditions applying a transcriptomic approach

    NARCIS (Netherlands)

    Zeisberger, Steffen M.; Zoller, Stefan; Riegel, Mariluce; Chen, Shuhua; Krenning, Guido; Harmsen, Martin C.; Sachinidis, Agapios; Zisch, Andreas H.

    Establishment of fetal bovine serum (FBS)-free cell culture conditions is essential for transplantation therapies. Blood-derived endothelial colony-forming cells (ECFCs) are potential candidates for regenerative medicine applications. ECFCs were isolated from term umbilical cord blood units and

  20. The granulocyte macrophage–colony stimulating factor surface modified MB49 bladder cancer stem cells vaccine against metastatic bladder cancer

    Directory of Open Access Journals (Sweden)

    Yong-tong Zhu

    2014-07-01

    Full Text Available The MB49 bladder cancer cell vaccine was effective against bladder cancer in the mice model in previous studies. However, part of the tumors regrew as the vaccine could not eliminate the cancer stem cells (CSCs. MB49 bladder cancer stem cells (MCSCs were isolated by a combination of the limited dilution method and the serum free culture medium method. MCSCs possessed higher expression of CD133, CD44, OCT4, NANOG, and ABCG2, the ability of differentiation, higher proliferative abilities, lower susceptibility to chemotherapy, greater migration in vitro, and stronger tumorigenic abilities in vivo. Then streptavidin–mouse granulocyte macrophage–colony stimulating factor (SA–mGM–CSF MCSCs vaccine was prepared. SA–mGM–CSF MCSCs vaccine extended the survival of the mice and inhibited the growth of tumor in protective, therapeutic, memorial and specific immune response experiments. The level of immunoglobulin G and the ratio of dendritic cells and CD4+ and CD8+ T cells were highest in the experimental group when compared to those in other four control groups, as well as for the cytotoxicity assay. We demonstrated that SA–mGM–CSF MCSCs vaccine induces an antitumor immune response to metastatic bladder cancer.

  1. Granulocyte colony-stimulating factor impairs CD8(+) T cell functionality by interfering with central activation elements.

    Science.gov (United States)

    Bunse, C E; Tischer, S; Lahrberg, J; Oelke, M; Figueiredo, C; Blasczyk, R; Eiz-Vesper, B

    2016-07-01

    Besides mobilizing stem cells into the periphery, granulocyte colony-stimulating factor (G-CSF) has been shown to influence various types of innate and adaptive immune cells. For example, it impairs the effector function of cytotoxic T lymphocytes (CTLs). It is assumed that this effect is mediated indirectly by monocytes, regulatory T cells and immunomodulatory cytokines influenced by G-CSF. In this study, isolated G-CSF-treated CD8(+) T cells were stimulated antigen-dependently with peptide-major histocompatibility complex (pMHC)-coupled artificial antigen-presenting cells (aAPCs) or stimulated antigen-independently with anti-CD3/CD28 stimulator beads. By measuring the changes in interferon (IFN)-γ and granzyme B expression at the mRNA and protein level, we showed for the first time that G-CSF has a direct effect on CD8(+) CTLs, which was confirmed based on the reduced production of IFN-γ and granzyme B by the cytotoxic T cell line TALL-104 after G-CSF treatment. By investigating further elements affected by G-CSF in CTLs from stem cell donors and untreated controls, we found a decreased phosphorylation of extracellular-regulated kinase (ERK)1/2, lymphocyte-specific protein tyrosine kinase (Lck) and CD3ζ after G-CSF treatment. Additionally, miRNA-155 and activation marker expression levels were reduced. In summary, our results show that G-CSF directly influences the effector function of cytotoxic CD8(+) T cells and affects various elements of T cell activation. © 2016 British Society for Immunology.

  2. Macrophage colony-stimulating factor receptor marks and regulates a fetal myeloid-primed B-cell progenitor in mice.

    Science.gov (United States)

    Zriwil, Alya; Böiers, Charlotta; Wittmann, Lilian; Green, Joanna C A; Woll, Petter S; Jacobsen, Sten Eirik W; Sitnicka, Ewa

    2016-07-14

    Although it is well established that unique B-cell lineages develop through distinct regulatory mechanisms during embryonic development, much less is understood about the differences between embryonic and adult B-cell progenitor cells, likely to underpin the genetics and biology of infant and childhood PreB acute lymphoblastic leukemia (PreB-ALL), initiated by distinct leukemia-initiating translocations during embryonic development. Herein, we establish that a distinct subset of the earliest CD19(+) B-cell progenitors emerging in the E13.5 mouse fetal liver express the colony-stimulating factor-1 receptor (CSF1R), previously thought to be expressed, and play a lineage-restricted role in development of myeloid lineages, and macrophages in particular. These early embryonic CSF1R(+)CD19(+) ProB cells also express multiple other myeloid genes and, in line with this, possess residual myeloid as well as B-cell, but not T-cell lineage potential. Notably, these CSF1R(+) myeloid-primed ProB cells are uniquely present in a narrow window of embryonic fetal liver hematopoiesis and do not persist in adult bone marrow. Moreover, analysis of CSF1R-deficient mice establishes a distinct role of CSF1R in fetal B-lymphopoiesis. CSF1R(+) myeloid-primed embryonic ProB cells are relevant for infant and childhood PreB-ALLs, which frequently have a bi-phenotypic B-myeloid phenotype, and in which CSF1R-rearrangements have recently been reported. © 2016 by The American Society of Hematology.

  3. Effect of basic fibroblast growth factor on pluripotent marker expression and colony forming unit capacity of stem cells isolated from human exfoliated deciduous teeth.

    Science.gov (United States)

    Sukarawan, Waleerat; Nowwarote, Nunthawan; Kerdpon, Piyarat; Pavasant, Prasit; Osathanon, Thanaphum

    2014-07-01

    Human dental pulp of exfoliated deciduous teeth contains the population of cells that exhibited mesenchymal stem cell (MSC) characters. Though, a cell amplification process is indeed required to secure an adequate cell number for such a potential employment. Several publications suggested the alteration of MSCs upon in vitro culture, for example, the decrease in proliferation and the loss of stem cell characters. Here, we investigated an influence of basic fibroblast growth factor (bFGF) on stem cells isolated from human exfoliated deciduous teeth (SHEDs) with respect to cell proliferation, colony forming unit efficiency and stem cell marker expression in both short- and long-term cultures. For short-term bFGF treatment, SHEDs were treated with bFGF for 48 h. While, in long-term bFGF supplementation, SHEDs were maintained in culture and continuous passage upon confluence in medium supplemented with bFGF. Cells at passage (P) 5 and 10 were employed for characterization. Our results showed that short-term bFGF treatment enhanced OCT4, REX1, and NANOG mRNA expression as well as colony forming unit ability. The FGFR inhibitor pretreatment was able to attenuate the influence of bFGF on pluripotent stem cell marker expression, confirming bFGF function. In addition, cells cultured in high passage number had decreased in cell proliferation, colony forming unit capacity, and pluripotent stem cell maker mRNA expression. However, bFGF supplementation in culture medium enhanced both pluripotent stem cell marker expression and colony forming unit capacity in later passage, though the effect was not robust. Together, these results indicate that high passage number may attenuate pluripotent properties of SHEDs and bFGF supplementation could be the beneficial approach to maintain SHEDs' stemness properties.

  4. Stem cells are units of natural selection for tissue formation, for germline development, and in cancer development.

    Science.gov (United States)

    Weissman, Irving L

    2015-07-21

    It is obvious that natural selection operates at the level of individuals and collections of individuals. Nearly two decades ago we showed that in multi-individual colonies of protochordate colonial tunicates sharing a blood circulation, there exists an exchange of somatic stem cells and germline stem cells, resulting in somatic chimeras and stem cell competitions for gonadal niches. Stem cells are unlike other cells in the body in that they alone self-renew, so that they form clones that are perpetuated for the life of the organism. Stem cell competitions have allowed the emergence of competitive somatic and germline stem cell clones. Highly successful germline stem cells usually outcompete less successful competitors both in the gonads of the genotype partner from which they arise and in the gonads of the natural parabiotic partners. Therefore, natural selection also operates at the level of germline stem cell clones. In the colonial tunicate Botryllus schlosseri the formation of natural parabionts is prevented by a single-locus highly polymorphic histocompatibility gene called Botryllus histocompatibility factor. This limits germline stem cell predation to kin, as the locus has hundreds of alleles. We show that in mice germline stem cells compete for gonad niches, and in mice and humans, blood-forming stem cells also compete for bone marrow niches. We show that the clonal progression from blood-forming stem cells to acute leukemias by successive genetic and epigenetic events in blood stem cells also involves competition and selection between clones and propose that this is a general theme in cancer.

  5. Effect of Supplementation of Branched Chain Fatty Acid on Colony of Ruminal Bacteria and Cell of Protozoa

    Directory of Open Access Journals (Sweden)

    W Suryapratama

    2009-05-01

    Full Text Available A study was conducted to evaluate the potential of branched-chain volatile fatty acids (isobutyric, α-methylbutyric and β-methylbutiric that supplemented into the diet on the colony of ruminal bacteria and the cell of protozoa population. Five progeny Friesian Holstein males with initial weight 348±29 kg were used in a 5x5 Latin square design (30-d periods. The basal diet composed of 55% forage and 45% concentrate containing 10.5 MJ ME/kg and 15% crude protein (CP. There were five dietary treatments where A: basal diet, B: A+139 mg urea/kg W0.75, C: B+28 mg CaSO4/kg W0.75, D: C+0.05 mM isobutyric acid+0.05 mM β-methylbutyric acid, and E: D+0.05 mM α-methylbutyric acid. Rearing period was 30 days, consists of feed adaptation period 20 days, then growth observation was done within the last 10 days. Collection of ruminal fluid was done within the last day of observation period, and took 3-4 h after the feeding. The results showed that supplementation branched chain volatile fatty acids did not significant affect on the number of colonies of bacteria and protozoa population, but the significant effect (P<0.05 on the concentration of branched chain volatile fatty acids in the rumen fluid. The supplementation of α-methylbutyric (P <0.05 decreased of concentration of isobutyric and isovaleric in rumen fluid than the other treatments. It is concluded that supplementation of branched chain volatile fatty acids not used by rumen bacteria for their growth but for the elongation of fatty acid synthesis. The supplementation of branched chain volatile fatty acids was 0.05 mM not enough strong influence on the growth of colony of rumen bacteria. (Animal Production 11(2: 129-134 (2009 Key Words: rumen fermentation, branched-chain fatty acid, ruminal bacteria, protozoa

  6. Genistein promotes endothelial colony-forming cell (ECFC bioactivities and cardiac regeneration in myocardial infarction.

    Directory of Open Access Journals (Sweden)

    Sang Hun Lee

    Full Text Available Although stem cell-mediated treatment of ischemic diseases offers significant therapeutic promise, the limitation in the therapeutic efficacy of transplanted stem cells in vivo because of poor engraftment remains a challenge. Several strategies aimed at improving survival and engraftment of stem cells in the ischemic myocardium have been developed, such as cell transplantation in combination with growth factor delivery, genetic modification of stem cells, and/or cell therapy using scaffolds. To improve therapeutic efficacy, we investigated the effects of genistein on the engraftment of transplanted ECFCs in an acute myocardial ischemia model.We found that genistein treatment enhanced ECFCs' migration and proliferation, which was accompanied by increases in the expression of ILK, α-parvin, F-actin, and phospholylation of ERK 1/2 signaling. Transplantation of genistein-stimulates ECFCs (GS-ECFCs into myocardial ischemic sites in vivo induced cellular proliferation and secretion of angiogenic cytokines at the ischemic sites and thereby enhanced neovascularization and decreased myocardial fibrosis as well as improved cardiac function, as shown by echocardiography. Taken together, these data suggest that pretreatment of ECFCs with genistein prior to transplantation can improve the regenerative potential in ischemic tissues, providing a novel strategy in adult stem cell therapy for ischemic diseases.

  7. Treatment with granulocyte colony-stimulating factor decreases the capacity of hematopoietic progenitor cells for generation of lymphocytes in human immunodeficiency virus-infected persons

    DEFF Research Database (Denmark)

    Nielsen, Susanne Dam; Clark, D R; Hutchings, M

    1999-01-01

    An obstacle to stem cell gene therapy for AIDS is the limited numbers of hematopoietic progenitors available. Granulocyte colony-stimulating factor (G-CSF) is used for mobilization of progenitors, but little is known about the functional characteristics of mobilized progenitors, and immature and ...

  8. Studies on colony specificity in the compound ascidian, Botryllus primigenus Oka. I. Initiation of "nonfusion" reaction with special reference to blood cells infiltration.

    Science.gov (United States)

    Taneda, Y; Watanabe, H

    1982-01-01

    When two incompatible colonies of the compound ascidian, Botryllus primigenus Oka come into contact, a specific rejection, called "nonfusion" reaction (NFR), always occurs in the contact area between them. At the beginning of the NFR, concentrations of cells were always observed near the ampullae tips. In the present study, it was revealed that these cells appear to be blood cells infiltrating through the ampullae and were identified as morula cells (vanadocytes). When India ink was injected into vessels prior to the occurrence of NFR, it leaked from the tips of the ampullae into the test matrix, suggesting an increase in the permeability of the ampullar epidermis. Experimental studies to elucidate the mechanism of NFR were carried out. Contact between a colony piece and a zooid-free ampullae fragment or overlapping of one colony to another, respectively, resulted in NFR only at one side of a pair. Furthermore, in stage 3 of NFR, when an opaque area was pushed with a pair of forceps and the blood in this area was transferred to healthy part of vessels, the stoppage of blood flow and subsequent contraction of vessels always took place in the latter. These observations suggest that ampullae penetration into the opposite colony is essential to NFR and that NFR is directly initiated in the ampullar lumen.

  9. Focal Adhesion Kinase regulates cell-cell contact formation in epithelial cells via modulation of Rho

    International Nuclear Information System (INIS)

    Playford, Martin P.; Vadali, Kavita; Cai Xinming; Burridge, Keith; Schaller, Michael D.

    2008-01-01

    Focal Adhesion Kinase (FAK) is a non-receptor tyrosine kinase that plays a key role in cellular processes such as cell adhesion, migration, proliferation and survival. Recent studies have also implicated FAK in the regulation of cell-cell adhesion. Here, evidence is presented showing that siRNA-mediated suppression of FAK levels in NBT-II cells and expression of dominant negative mutants of FAK caused loss of epithelial cell morphology and inhibited the formation of cell-cell adhesions. Rac and Rho have been implicated in the regulation of cell-cell adhesions and can be regulated by FAK signaling. Expression of active Rac or Rho in NBT-II cells disrupted formation of cell-cell contacts, thus promoting a phenotype similar to FAK-depleted cells. The loss of intercellular contacts in FAK-depleted cells is prevented upon expression of a dominant negative Rho mutant, but not a dominant negative Rac mutant. Inhibition of FAK decreased tyrosine phosphorylation of p190RhoGAP and elevated the level of GTP-bound Rho. This suggests that FAK regulates cell-cell contact formation by regulation of Rho

  10. Spatio-temporal morphology changes in and quenching effects on the 2D spreading dynamics of cell colonies in both plain and methylcellulose-containing culture media.

    Science.gov (United States)

    Muzzio, N E; Pasquale, M A; Huergo, M A C; Bolzán, A E; González, P H; Arvia, A J

    2016-06-01

    To deal with complex systems, microscopic and global approaches become of particular interest. Our previous results from the dynamics of large cell colonies indicated that their 2D front roughness dynamics is compatible with the standard Kardar-Parisi-Zhang (KPZ) or the quenched KPZ equations either in plain or methylcellulose (MC)-containing gel culture media, respectively. In both cases, the influence of a non-uniform distribution of the colony constituents was significant. These results encouraged us to investigate the overall dynamics of those systems considering the morphology and size, the duplication rate, and the motility of single cells. For this purpose, colonies with different cell populations (N) exhibiting quasi-circular and quasi-linear growth fronts in plain and MC-containing culture media are investigated. For small N, the average radial front velocity and its change with time depend on MC concentration. MC in the medium interferes with cell mitosis, contributes to the local enlargement of cells, and increases the distribution of spatio-temporal cell density heterogeneities. Colony spreading in MC-containing media proceeds under two main quenching effects, I and II; the former mainly depending on the culture medium composition and structure and the latter caused by the distribution of enlarged local cell domains. For large N, colony spreading occurs at constant velocity. The characteristics of cell motility, assessed by measuring their trajectories and the corresponding velocity field, reflect the effect of enlarged, slow-moving cells and the structure of the medium. Local average cell size distribution and individual cell motility data from plain and MC-containing media are qualitatively consistent with the predictions of both the extended cellular Potts models and the observed transition of the front roughness dynamics from a standard KPZ to a quenched KPZ. In this case, quenching effects I and II cooperate and give rise to the quenched

  11. Formation of reactive oxygen species in rat epithelial cells upon ...

    Indian Academy of Sciences (India)

    Unknown

    < 100 nm) that contributed 31% to the particle number. In our study, we investigated the influence of fly ash on the promotion of early inflammatory reactions like the formation of reactive oxygen species (ROS) in rat lung epithelial cells (RLE-6TN). Furthermore, we determined the formation of nitric oxide (NO). The cells show a.

  12. Formation of reactive oxygen species in rat epithelial cells upon ...

    Indian Academy of Sciences (India)

    In our study, we investigated the influence of fly ash on the promotion of early inflammatory reactions like the formation of reactive oxygen species (ROS) in rat lung epithelial cells (RLE-6TN). Furthermore, we determined the formation of nitric oxide (NO). The cells show a clear dose-response relationship concerning the ...

  13. OCT4 expression in outgrowth colonies derived from porcine inner cell masses and epiblasts

    DEFF Research Database (Denmark)

    Rasmussen, M A; Wolf, X A; Schauser, K

    2011-01-01

    on the relationship between OCT4 expression and embryonic stem cell (ESC)-like morphology. A total of 104 zona pellucida-enclosed and 101 hatched blastocysts were subjected to four different methods of ICM and epiblast isolation, respectively: Manual isolation, immunosurgery, immunosurgery with manual cleaning......, or whole blastocyst culture. OCs were established on mouse embryonic fibroblast (MEF) cells and categorized according to morphology and OCT4 staining. Although all isolation methods resulted in ESC-like OCs, immunosurgery with manual cleaning yielded significantly higher rates of ICM/epiblast attachment...

  14. Initial colony morphology-based selection for iPS cells derived from adult fibroblasts is substantially improved by temporary UTF1-based selection.

    Directory of Open Access Journals (Sweden)

    Kurt Pfannkuche

    Full Text Available BACKGROUND: Somatic cells can be reprogrammed into induced pluripotent stem (iPS cells. Recently, selection of fully reprogrammed cells was achieved based on colony morphology reminiscent of embryonic stem (ES cells. The maintenance of pluripotency was analysed. METHODOLOGY/PRINCIPAL FINDINGS: Clonal murine iPS cell line TiB7-4, which was derived from adult fibroblasts, was analysed for maintenance of pluripotency. Colony morphology, expression of pluripotency factors and stage specific embryonic antigen 1 (SSEA1 were analysed by real time PCR and flow cytometry. We found the iPS cell line TiB7-4 and its subclones to be rather diverse and exhibiting a tendency towards spontaneous differentiation and loss of pluripotency independent of their initial colony morphology. In contrast an undifferentiated transcription factor 1 (UTF1 promoter-driven G418 (Neo resistance significantly improved the quality of these iPS cells. After selection with UTF-Neo for two weeks iPS subclones could be stably maintained for at least 40 passages in culture and differentiate into all three germ layers. As control, a construct expressing G418 resistance under the control of the ubiquitously active SV40 early promoter formed subclones with different colony morphology. Some of these subclones could be cultured for at least 12 passages without loosing their pluripotency, but loss of pluripotency eventually occured in an unpredictable manner and was independent of the subclones' initial morphology and SSEA1 expression. A UTF-Neo-based selection of a whole population of TiB7-4 without further subcloning resulted in the generation of cultures with up to 99% SSEA1 positive cells under stringent selection conditions. CONCLUSIONS: Our data indicate that temporary selection using a genetic UTF1-based system can generate homogenous pluripotent iPS cells that can be maintained without permanent selection pressure.

  15. Role of Granulocyte-Macrophage Colony-Stimulating Factor Production by T Cells duringMycobacterium tuberculosisInfection.

    Science.gov (United States)

    Rothchild, Alissa C; Stowell, Britni; Goyal, Girija; Nunes-Alves, Cláudio; Yang, Qianting; Papavinasasundaram, Kadamba; Sassetti, Christopher M; Dranoff, Glenn; Chen, Xinchun; Lee, Jinhee; Behar, Samuel M

    2017-10-24

    Mice deficient for granulocyte-macrophage colony-stimulating factor (GM-CSF -/- ) are highly susceptible to infection with Mycobacterium tuberculosis , and clinical data have shown that anti-GM-CSF neutralizing antibodies can lead to increased susceptibility to tuberculosis in otherwise healthy people. GM-CSF activates human and murine macrophages to inhibit intracellular M. tuberculosis growth. We have previously shown that GM-CSF produced by iNKT cells inhibits growth of M. tuberculosis However, the more general role of T cell-derived GM-CSF during infection has not been defined and how GM-CSF activates macrophages to inhibit bacterial growth is unknown. Here we demonstrate that, in addition to nonconventional T cells, conventional T cells also produce GM-CSF during M. tuberculosis infection. Early during infection, nonconventional iNKT cells and γδ T cells are the main source of GM-CSF, a role subsequently assumed by conventional CD4 + T cells as the infection progresses. M. tuberculosis -specific T cells producing GM-CSF are also detected in the peripheral blood of infected people. Under conditions where nonhematopoietic production of GM-CSF is deficient, T cell production of GM-CSF is protective and required for control of M. tuberculosis infection. However, GM-CSF is not required for T cell-mediated protection in settings where GM-CSF is produced by other cell types. Finally, using an in vitro macrophage infection model, we demonstrate that GM-CSF inhibition of M. tuberculosis growth requires the expression of peroxisome proliferator-activated receptor gamma (PPARγ). Thus, we identified GM-CSF production as a novel T cell effector function. These findings suggest that a strategy augmenting T cell production of GM-CSF could enhance host resistance against M. tuberculosis IMPORTANCE Mycobacterium tuberculosis is the bacterium that causes tuberculosis, the leading cause of death by any infection worldwide. T cells are critical components of the immune

  16. Cholesterol inhibits entotic cell-in-cell formation and actomyosin contraction.

    Science.gov (United States)

    Ruan, Banzhan; Zhang, Bo; Chen, Ang; Yuan, Long; Liang, Jianqing; Wang, Manna; Zhang, Zhengrong; Fan, Jie; Yu, Xiaochen; Zhang, Xin; Niu, Zubiao; Zheng, You; Gu, Songzhi; Liu, Xiaoqing; Du, Hongli; Wang, Jufang; Hu, Xianwen; Gao, Lihua; Chen, Zhaolie; Huang, Hongyan; Wang, Xiaoning; Sun, Qiang

    2018-01-01

    Cell-in-cell structure is prevalent in human cancer, and associated with several specific pathophysiological phenomena. Although cell membrane adhesion molecules were found critical for cell-in-cell formation, the roles of other membrane components, such as lipids, remain to be explored. In this study, we attempted to investigate the effects of cholesterol and phospholipids on the formation of cell-in-cell structures by utilizing liposome as a vector. We found that Lipofectamine-2000, the reagent commonly used for routine transfection, could significantly reduce entotic cell-in-cell formation in a cell-specific manner, which is correlated with suppressed actomyosin contraction as indicated by reduced β-actin expression and myosin light chain phosphorylation. The influence on cell-in-cell formation was likely dictated by specific liposome components as some liposomes affected cell-in-cell formation while some others didn't. Screening on a limited number of lipids, the major components of liposome, identified phosphatidylethanolamine (PE), stearamide (SA), lysophosphatidic acid (LPA) and cholesterol (CHOL) as the inhibitors of cell-in-cell formation. Importantly, cholesterol treatment significantly inhibited myosin light chain phosphorylation, which resembles the effect of Lipofectamine-2000, suggesting cholesterol might be partially responsible for liposomes' effects on cell-in-cell formation. Together, our findings supporting a role of membrane lipids and cholesterol in cell-in-cell formation probably via regulating actomyosin contraction. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. Granulocyte-colony stimulating factor and umbilical cord blood cell transplantation: Synergistic therapies for the treatment of traumatic brain injury

    Directory of Open Access Journals (Sweden)

    Michael G Liska

    2017-01-01

    Full Text Available Traumatic brain injury (TBI is now characterized as a progressive, degenerative disease and continues to stand as a prevalent cause of death and disability. The pathophysiology of TBI is complex, with a variety of secondary cell death pathways occurring which may persist chronically following the initial cerebral insult. Current therapeutic options for TBI are minimal, with surgical intervention or rehabilitation therapy existing as the only viable treatments. Considering the success of stem-cell therapies in various other neurological diseases, their use has been proposed as a potential potent therapy for patients suffering TBI. Moreover, stem cells are highly amenable to adjunctive use with other therapies, providing an opportunity to overcome the inherent limitations of using a single therapeutic agent. Our research has verified this additive potential by demonstrating the efficacy of co-delivering human umbilical cord blood (hUCB cells with granulocyte-colony stimulating factor (G-CSF in a murine model of TBI, providing encouraging results which support the potential of this approach to treat patients suffering from TBI. These findings justify ongoing research toward uncovering the mechanisms which underlie the functional improvements exhibited by hUCB + G-CSF combination therapy, thereby facilitating its safe and effect transition into the clinic. This paper is a review article. Referred literature in this paper has been listed in the reference section. The datasets supporting the conclusions of this article are available online by searching various databases, including PubMed. Some original points in this article come from the laboratory practice in our research center and the authors' experiences.

  18. Treatment with granulocyte colony-stimulating factor decreases the capacity of hematopoietic progenitor cells for generation of lymphocytes in human immunodeficiency virus-infected persons

    DEFF Research Database (Denmark)

    Nielsen, Susanne Dam; Clark, D R; Hutchings, M

    1999-01-01

    of CD34+ progenitor cells to generate lymphocytes was examined by use of thymic organ cultures. The mean number of lymphocytes generated per CD34+ cell on day 0 was 0.72 and on day 4 was 0.09 (PCD4+ cells generated per CD34+ cell was significantly reduced after G-CSF treatment......An obstacle to stem cell gene therapy for AIDS is the limited numbers of hematopoietic progenitors available. Granulocyte colony-stimulating factor (G-CSF) is used for mobilization of progenitors, but little is known about the functional characteristics of mobilized progenitors, and immature and T...

  19. Self-Organization of Stem Cell Colonies and of Early Mammalian Embryos: Recent Experiments Shed New Light on the Role of Autonomy vs. External Instructions in Basic Body Plan Development

    Directory of Open Access Journals (Sweden)

    Hans-Werner Denker

    2016-10-01

    Full Text Available “Organoids”, i.e., complex structures that can develop when pluripotent or multipotent stem cells are maintained in three-dimensional cultures, have become a new area of interest in stem cell research. Hopes have grown that when focussing experimentally on the mechanisms behind this type of in vitro morphogenesis, research aiming at tissue and organ replacements can be boosted. Processes leading to the formation of organoids in vitro are now often addressed as self-organization, a term referring to the formation of complex tissue architecture in groups of cells without depending on specific instruction provided by other cells or tissues. The present article focuses on recent reports using the term self-organization in the context of studies on embryogenesis, specifically addressing pattern formation processes in human blastocysts attaching in vitro, or in colonies of pluripotent stem cells (“gastruloids”. These morphogenetic processes are of particular interest because, during development in vivo, they lead to basic body plan formation and individuation. Since improved methodologies like those employed by the cited authors became available, early embryonic pattern formation/self-organization appears to evolve now as a research topic of its own. This review discusses concepts concerning the involved mechanisms, focussing on autonomy of basic body plan development vs. dependence on external signals, as possibly provided by implantation in the uterus, and it addresses biological differences between an early mammalian embryo, e.g., a morula, and a cluster of pluripotent stem cells. It is concluded that, apart from being of considerable biological interest, the described type of research needs to be contemplated carefully with regard to ethical implications when performed with human cells.

  20. Diffusive boundary layers of the colony-forming plankton alga Phaeocystis sp - implications for nutrient uptake and cellular growth

    DEFF Research Database (Denmark)

    Ploug, H.; Stolte, W.; Jørgensen, BB

    1999-01-01

    with concentrations of 2 and 0.2 mu M, respectively, was sufficient to support nutrient demands for 1 cell doubling in colonies in 6-10 h, respectively, at a shear rate of 0.1 s(-1). The same nutrient concentration levels could theoretically support nutrient demands of single cells for one cell doubling within 2-3 h....... It was concluded that the lower grazing pressure in the size class of colonies relative to that of single free-living cells may be more important for colony formation than nutrient concentrations....

  1. Integrin LFA-1 regulates cell adhesion via transient clutch formation.

    Science.gov (United States)

    Ishibashi, Munenori; Miyanaga, Yukihiro; Matsuoka, Satomi; Kozuka, Jun; Togashi, Yuichi; Kinashi, Tatsuo; Ueda, Masahiro

    2015-08-21

    Integrin LFA-1 regulates immune cell adhesion and trafficking by binding to ICAM-1 upon chemokine stimulation. Integrin-mediated clutch formation between extracellular ICAM-1 and the intracellular actin cytoskeleton is important for cell adhesion. We applied single-molecule tracking analysis to LFA-1 and ICAM-1 in living cells to examine the ligand-binding kinetics and mobility of the molecular clutch under chemokine-induced physiological adhesion and Mn(2+)-induced tight adhesion. Our results show a transient LFA-1-mediated clutch formation that lasts a few seconds and leads to a transient lower-mobility is sufficient to promote cell adhesion. Stable clutch formation was observed for Mn(2+)-induced high affinity LFA-1, but was not required for physiological adhesion. We propose that fast cycling of the clutch formation by intermediate-affinity integrin enables dynamic cell adhesion and migration. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  2. The optimal use of granulocyte macrophage colony stimulating factor in radiation induced mucositis in head and neck squamous cell carcinoma.

    Directory of Open Access Journals (Sweden)

    Patni Nidhi

    2005-01-01

    Full Text Available Objective: Evaluation of response of granulocyte macrophage colony stimulating factor (GM-CSF on acute radiation toxicity profile in head and neck squamous cell carcinoma. Methods and Materials: Thirty three patients with proven stage I or II head & neck carcinoma received conventional external beam radiation therapy. Out of these, six patients received postoperative adjuvant therapy while remaining 27 received definitive RT. Patients were given 100 mcg GM-CSF subcutaneously per day along with radiation after they developed grade 2 mucositis and /or grade 2 dysphagia and / or complained of moderate pain. GM-CSF was administered till there was a subjective relief or objective response. Patients were evaluated for oral ulceration, swallowing status, pain and weight loss. Response to the treatment and patient outcome was assessed. Results: There was a decreased severity of mucositis and dysphagia in the evaluated patients. None of the patients suffered severe pain or required opioids. The mean weight loss was only 1.94%. Minimal side effects were experienced with GM-CSF. Conclusions: GM-CSF reduces the severity of acute side effects of radiation therapy thereby allowing completion of the treatment without interruption. Its remarkable response needs to be evaluated further in large randomized trials. The time of initiation and cessation of GM-CSF during radiation therapy and the required dose needs to be established.

  3. Treatment with granulocyte colony-stimulating factor decreases the capacity of hematopoietic progenitor cells for generation of lymphocytes in human immunodeficiency virus-infected persons

    DEFF Research Database (Denmark)

    Nielsen, S D; Clark, D R; Hutchings, M

    1999-01-01

    An obstacle to stem cell gene therapy for AIDS is the limited numbers of hematopoietic progenitors available. Granulocyte colony-stimulating factor (G-CSF) is used for mobilization of progenitors, but little is known about the functional characteristics of mobilized progenitors, and immature and T...... of CD34+ progenitor cells to generate lymphocytes was examined by use of thymic organ cultures. The mean number of lymphocytes generated per CD34+ cell on day 0 was 0.72 and on day 4 was 0.09 (Pgenerated per CD34+ cell was significantly reduced after G-CSF treatment...

  4. Lipocalin-2 inhibits osteoclast formation by suppressing the proliferation and differentiation of osteoclast lineage cells

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyun-Ju, E-mail: biohjk@knu.ac.kr [Department of Molecular Medicine, Cell and Matrix Research Institute, Clinical Trial Center, BK21 Plus KNU Biomedical Convergence Program, School of Medicine, Kyungpook National University, Daegu 700-422 (Korea, Republic of); Yoon, Hye-Jin [Department of Molecular Medicine, Cell and Matrix Research Institute, Clinical Trial Center, BK21 Plus KNU Biomedical Convergence Program, School of Medicine, Kyungpook National University, Daegu 700-422 (Korea, Republic of); Yoon, Kyung-Ae [Department of Orthopedic Surgery, Skeletal Diseases Genome Research Center, School of Medicine, Kyungpook National University, Daegu 700-422 (Korea, Republic of); Gwon, Mi-Ri; Jin Seong, Sook [Department of Molecular Medicine, Cell and Matrix Research Institute, Clinical Trial Center, BK21 Plus KNU Biomedical Convergence Program, School of Medicine, Kyungpook National University, Daegu 700-422 (Korea, Republic of); Suk, Kyoungho [Department of Pharmacology, School of Medicine, Kyungpook National University, Daegu 700-422 (Korea, Republic of); Kim, Shin-Yoon [Department of Orthopedic Surgery, Skeletal Diseases Genome Research Center, School of Medicine, Kyungpook National University, Daegu 700-422 (Korea, Republic of); Yoon, Young-Ran, E-mail: yry@knu.ac.kr [Department of Molecular Medicine, Cell and Matrix Research Institute, Clinical Trial Center, BK21 Plus KNU Biomedical Convergence Program, School of Medicine, Kyungpook National University, Daegu 700-422 (Korea, Republic of)

    2015-06-10

    Lipocalin-2 (LCN2) is a member of the lipocalin superfamily and plays a critical role in the regulation of various physiological processes, such as inflammation and obesity. In this study, we report that LCN2 negatively modulates the proliferation and differentiation of osteoclast precursors, resulting in impaired osteoclast formation. The overexpression of LCN2 in bone marrow-derived macrophages or the addition of recombinant LCN2 protein inhibits the formation of multinuclear osteoclasts. LCN2 suppresses macrophage colony-stimulating factor (M-CSF)-induced proliferation of osteoclast precursor cells without affecting their apoptotic cell death. Interestingly, LCN2 decreases the expression of the M-CSF receptor, c-Fms, and subsequently blocks its downstream signaling cascades. In addition, LCN2 inhibits RANKL-induced osteoclast differentiation and attenuates the expression of c-Fos and nuclear factor of activated T cells c1 (NFATc1), which are important modulators in osteoclastogenesis. Mechanistically, LCN2 inhibits NF-κB signaling pathways, as demonstrated by the suppression of IκBα phosphorylation, nuclear translocation of p65, and NF-κB transcriptional activity. Thus, LCN2 is an anti-osteoclastogenic molecule that exerts its effects by retarding the proliferation and differentiation of osteoclast lineage cells. - Highlights: • LCN2 expression is regulated during osteoclast development. • LCN2 suppresses M-CSF-mediated osteoclast precursor proliferation. • LCN2 inhibits RANKL-induced osteoclast differentiation.

  5. Dysregulation of endothelial colony-forming cell function by a negative feedback loop of circulating miR-146a and -146b in cardiovascular disease patients.

    Directory of Open Access Journals (Sweden)

    Ting-Yu Chang

    Full Text Available Functional impairment of endothelial colony-forming cells (ECFCs, a specific cell lineage of endothelial progenitor cells (EPCs is highly associated with the severity of coronary artery disease (CAD, the most common type of cardiovascular disease (CVD. Emerging evidence show that circulating microRNAs (miRNAs in CAD patients' body fluid hold a great potential as biomarkers. However, our knowledge of the role of circulating miRNA in regulating the function of ECFCs and the progression of CAD is still in its infancy. We showed that when ECFCs from healthy volunteers were incubated with conditioned medium or purified exosomes of cultured CAD ECFCs, the secretory factors from CAD ECFCs dysregulated migration and tube formation ability of healthy ECFCs. It is known that exosomes influence the physiology of recipient cells by introducing RNAs including miRNAs. By using small RNA sequencing (smRNA-seq, we deciphered the circulating miRNome in the plasma of healthy individual and CAD patients, and found that the plasma miRNA spectrum from CAD patients was significantly different from that of healthy control. Interestingly, smRNA-seq of both healthy and CAD ECFCs showed that twelve miRNAs that had a higher expression in the plasma of CAD patients also showed higher expression in CAD ECFCs when compared with healthy control. This result suggests that these miRNAs may be involved in the regulation of ECFC functions. For identification of potential mRNA targets of the differentially expressed miRNA in CAD patients, cDNA microarray analysis was performed to identify the angiogenesis-related genes that were down-regulated in CAD ECFCs and Pearson's correlation were used to identify miRNAs that were negatively correlated with the identified angiogenesis-related genes. RT-qPCR analysis of the five miRNAs that negatively correlated with the down-regulated angiogenesis-related genes in plasma and ECFC of CAD patients showed miR-146a-5p and miR-146b-5p up

  6. Mathematical modeling of dormant cell formation in growing biofilm

    Directory of Open Access Journals (Sweden)

    Kotaro eChihara

    2015-05-01

    Full Text Available Understanding the dynamics of dormant cells in microbial biofilms, in which the bacteria are embedded in extracellular matrix, is important for developing successful antibiotic therapies against pathogenic bacteria. Although some of the molecular mechanisms leading to bacterial persistence have been speculated in planktonic bacterial cell, how dormant cells emerge in the biofilms of pathogenic bacteria such as Pseudomonas aeruginosa remains unclear. The present study proposes four hypotheses of dormant cell formation; stochastic process, nutrient-dependent, oxygen-dependent, and time-dependent processes. These hypotheses were implemented into a three-dimensional individual-based model of biofilm formation. Numerical simulations of the different mechanisms yielded qualitatively different spatiotemporal distributions of dormant cells in the growing biofilm. Based on these simulation results, we discuss what kinds of experimental studies are effective for discriminating dormant cell formation mechanisms in biofilms.

  7. Mathematical modeling of dormant cell formation in growing biofilm.

    Science.gov (United States)

    Chihara, Kotaro; Matsumoto, Shinya; Kagawa, Yuki; Tsuneda, Satoshi

    2015-01-01

    Understanding the dynamics of dormant cells in microbial biofilms, in which the bacteria are embedded in extracellular matrix, is important for developing successful antibiotic therapies against pathogenic bacteria. Although some of the molecular mechanisms leading to bacterial persistence have been speculated in planktonic bacterial cell, how dormant cells emerge in the biofilms of pathogenic bacteria such as Pseudomonas aeruginosa remains unclear. The present study proposes four hypotheses of dormant cell formation; stochastic process, nutrient-dependent, oxygen-dependent, and time-dependent processes. These hypotheses were implemented into a three-dimensional individual-based model of biofilm formation. Numerical simulations of the different mechanisms yielded qualitatively different spatiotemporal distributions of dormant cells in the growing biofilm. Based on these simulation results, we discuss what kinds of experimental studies are effective for discriminating dormant cell formation mechanisms in biofilms.

  8. Effect of administration timing of postchemotherapy granulocyte colony-stimulating factor on host-immune cell recovery and CD8+T-cell response.

    Science.gov (United States)

    Salem, Mohamed Labib; Nassef, Mohamed; Abdel Salam, Soha G R; Zidan, Abdelaziz; Mahmoud, Mohamed H; Badr, Gamal; Rubinstein, Mark; Cole, David

    2016-11-01

    Granulocyte colony-stimulating factor (G-CSF), a hematopoietic growth factor, is a standard supportive therapy given during cancer treatment. It induces acceleration in neutrophil recovery through stimulation of mobilization of hematopoietic progenitors. Given that the latter is also induced by chemotherapy itself, the timing of administration of G-CSF postchemotherapy might impact the resultant overall effects. The present study aimed to determine the optimal timing of G-CSF postchemotherapy to exert its optimal effects on the immune cell recovery and its impact on antigen-specific CD8 + T-cell response. B6 mice were treated once with cyclophosphamide (4 mg/mouse; CTX) and then daily with G-CSF (5 g/mouse) from Days 1-5, 2-5 or 5-9 post-CTX treatment. The total numbers of various immune cell types were analyzed on Days 7, 9 and 12 post-CTX treatment. To evaluate effects on CD8 + T-cell response, a pmel-1 transgenic mouse model was used in combination with prime boost peptide vaccination therapy. The total number of white blood cells (WBC), neutrophils, monocytes, lymphocytes, granulocytes and dendritic cells (DC) were significantly increased after G-CSF treatment in particular when G-CSF was administered from Days 2-5 post-CTX treatment. Application of this timing of G-CSF and CTX treatment after adoptive transfer of T-cells followed by prime-boost vaccination with antigenic peptide did not block the expansion of the donor pmel-1 CD8 + T-cells. In conclusion, adjusting the timing of treatment with G-CSF postchemotherapy can optimize its promoting effects on recovery of myeloid cells without altering the associated antigen-specific immunity.

  9. Suppression of T cell-induced osteoclast formation

    Energy Technology Data Exchange (ETDEWEB)

    Karieb, Sahar; Fox, Simon W., E-mail: Simon.fox@plymouth.ac.uk

    2013-07-12

    Highlights: •Genistein and coumestrol prevent activated T cell induced osteoclast formation. •Anti-TNF neutralising antibodies prevent the pro-osteoclastic effect of activated T cells. •Phytoestrogens inhibit T cell derived TNF alpha and inflammatory cytokine production. •Phytoestrogens have a broader range of anti-osteoclastic actions than other anti-resorptives. -- Abstract: Inhibition of T cell derived cytokine production could help suppress osteoclast differentiation in inflammatory skeletal disorders. Bisphosphonates are typically prescribed to prevent inflammatory bone loss but are not tolerated by all patients and are associated with an increased risk of osteonecrosis of the jaw. In light of this other anti-resorptives such as phytoestrogens are being considered. However the effect of phytoestrogens on T cell-induced osteoclast formation is unclear. The effect of genistein and coumestrol on activated T cell-induced osteoclastogenesis and cytokine production was therefore examined. Concentrations of genistein and coumestrol (10{sup −7} M) previously shown to directly inhibit osteoclast formation also suppressed the formation of TRAP positive osteoclast induced by con A activated T cells, which was dependent on inhibition of T cell derived TNF-α. While both reduced osteoclast formation their mechanism of action differed. The anti-osteoclastic effect of coumestrol was associated with a dual effect on con A induced T cell proliferation and activation; 10{sup −7} M coumestrol significantly reducing T cell number (0.36) and TNF-α (0.47), IL-1β (0.23) and IL-6 (0.35) expression, whereas genistein (10{sup −7} M) had no effect on T cell number but a more pronounced effect on T cell differentiation reducing expression of TNF-α (0.49), IL-1β (0.52), IL-6 (0.71) and RANKL (0.71). Phytoestrogens therefore prevent the pro-osteoclastic action of T cells suggesting they may have a role in the control of inflammatory bone loss.

  10. Predicting the distribution of spiral waves from cell properties in a developmental-path model of Dictyostelium pattern formation.

    Directory of Open Access Journals (Sweden)

    Daniel Geberth

    2009-07-01

    Full Text Available The slime mold Dictyostelium discoideum is one of the model systems of biological pattern formation. One of the most successful answers to the challenge of establishing a spiral wave pattern in a colony of homogeneously distributed D. discoideum cells has been the suggestion of a developmental path the cells follow (Lauzeral and coworkers. This is a well-defined change in properties each cell undergoes on a longer time scale than the typical dynamics of the cell. Here we show that this concept leads to an inhomogeneous and systematic spatial distribution of spiral waves, which can be predicted from the distribution of cells on the developmental path. We propose specific experiments for checking whether such systematics are also found in data and thus, indirectly, provide evidence of a developmental path.

  11. TRIM28 epigenetic corepressor is indispensable for stable induced pluripotent stem cell formation

    Directory of Open Access Journals (Sweden)

    Marta Klimczak

    2017-08-01

    Full Text Available Cellular reprogramming proceeds in a stepwise pathway initiated by binding and transcription of pluripotency factors followed by genome-wide epigenetic changes. Priming events, such as erasure of DNA methylation and chromatin remodeling determines the success of pluripotency acquisition later. Therefore, growing efforts are made to understand epigenetic regulatory network that makes reprogramming possible and efficient. Here, we analyze the role of transcriptional corepressor TRIM28, involved in heterochromatin formation, during the process of reprogramming of mouse somatic cells into induced pluripotent stem cells (iPS cells. We demonstrate that Trim28 knockdown (Trim28 KD causes that emerging iPS cells differentiate immediately back into MEFs therefore they fail to yield stable iPS cell colonies. To better comprehend the mechanism of TRIM28 action in reprogramming, we performed a reverse-phase protein array (RPPA using in excess of 300 different antibodies and compared the proteomic profiles of wild-type and Trim28 KD cells during reprogramming. We revealed the differences in the dynamics of reprogramming of wild-type and Trim28 KD cells. Interestingly, proteomic profile of Trim28 KD cells at the final stage of reprogramming resembled differentiated state rather than maintenance of pluripotency and self-renewal, strongly suggesting spontaneous differentiation of Trim28 KD cells back to their parental cell type. We also observed that action of TRIM28 in reprogramming is accompanied by differential enrichment of proteins involved in cell cycle, adhesion and stemness. Collectively, these results suggest that regulation of epigenetic modifications coordinated by TRIM28 plays a crucial role in reprogramming process.

  12. Adrenaline administration promotes the efficiency of granulocyte colony stimulating factor-mediated hematopoietic stem and progenitor cell mobilization in mice.

    Science.gov (United States)

    Chen, Chong; Cao, Jiang; Song, Xuguang; Zeng, Lingyu; Li, Zhenyu; Li, Yong; Xu, Kailin

    2013-01-01

    A high dose of granulocyte colony stimulating factor (G-CSF) is widely used to mobilize hematopoietic stem and progenitor cells (HSPC), but G-CSF is relatively inefficient and may cause adverse effects. Recently, adrenaline has been found to play important roles in HSPC mobilization. In this study, we explored whether adrenaline combined with G-CSF could induce HSPC mobilization in a mouse model. Mice were treated with adrenaline and either a high or low dose of G-CSF alone or in combination. Peripheral blood HSPC counts were evaluated by flow cytometry. Levels of bone marrow SDF-1 were measured by ELISA, the transcription of CXCR4 and SDF-1 was measured by real-time RT-PCR, and CXCR4 protein was detected by Western blot. Our results showed that adrenaline alone fails to mobilize HSPCs into the peripheral blood; however, when G-CSF and adrenaline are combined, the WBC counts and percentages of HSPCs are significantly higher compared to those in mice that received G-CSF alone. The combined use of adrenaline and G-CSF not only accelerated HSPC mobilization, but also enabled the efficient mobilization of HSPCs into the peripheral blood at lower doses of G-CSF. Adrenaline/G-CSF treatment also extensively downregulated levels of SDF-1 and CXCR4 in mouse bone marrow. These results demonstrated that adrenaline combined with G-CSF can induce HSPC mobilization by down-regulating the CXCR4/SDF-1 axis, indicating that the use of adrenaline may enable the use of reduced dosages or durations of G-CSF treatment, minimizing G-CSF-associated complications.

  13. Granulocyte colony-stimulating factor increases CD4+ T cell counts of human immunodeficiency virus-infected patients receiving stable, highly active antiretroviral therapy

    DEFF Research Database (Denmark)

    Aladdin, H; Ullum, H; Dam Nielsen, S.

    2000-01-01

    Thirty human immunodeficiency virus (HIV)-infected patients with CD4+ T cell counts active antiretroviral therapy (HAART) for at least 24 weeks were randomized to receive either placebo or granulocyte colony-stimulating factor (G-CSF; 0.3 mg/mL 3 times...... counts resulted from increases in CD45RO+ memory T cells and cells expressing the CD38 activation marker. Lymphocyte proliferative responses to phytohemagglutinin and Candida antigen decreased, whereas NK cell activity and plasma HIV RNA did not change during G-CSF treatment. After 24 weeks, all immune...... a week) for 12 weeks. Blood samples were collected at specified time points. G-CSF treatment enhanced the total lymphocyte count (P=.002) and increased CD3+ (P=.005), CD4+ (P=.03), and CD8+ (P=.004) T cell counts as well as numbers of CD3-CD16+CD56+ NK cells (P=.001). The increases in CD4+ and CD8+ cell...

  14. KIF11 Is Required for Spheroid Formation by Oesophageal and Colorectal Cancer Cells.

    Science.gov (United States)

    Imai, Takeharu; Oue, Naohide; Sentani, Kazuhiro; Sakamoto, Naoya; Uraoka, Naohiro; Egi, Hiroyuki; Hinoi, Takao; Ohdan, Hideki; Yoshida, Kazuhiro; Yasui, Wataru

    2017-01-01

    Oesophageal squamous cell carcinoma (ESCC) and colorectal cancer (CRC) are common types of human cancer. Spheroid colony formation is used to characterize cancer stem cell (CSCs). In the present study, we analyzed the significance of kinesin family 11 (KIF11 in human ESCC and CRC. Expression of KIF11 in 105 ESCC and 100 CRC cases was determined using immunohistochemistry. RNA interference was used to inhibit KIF11 expression in ESCC and CRC cell lines. In total, 61 out of 105 (58%) ESCC and 62 out of 100 (62%) CRC cases were positive for KIF11. Expression of KIF11 was not associated with any clinicopathological characteristics. Both the number and size of spheres produced by from TE-5 ESCC cells and DLD-1 CRC cells were significantly reduced upon KIF11 siRNA transfection compared to negative control siRNA transfection. These results indicate that KIF11 plays an important role in CSCs of ESCC and CRC. Copyright© 2017 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

  15. The Formation of Germ Cell for Organizational Learning

    Science.gov (United States)

    Ivaldi, Silvia; Scaratti, Giuseppe

    2016-01-01

    Purpose: The aim of the paper is to analyze the process of "germ cell" formation by framing it as an opportunity for promoting organizational learning and transformation. The paper aims to specifically answer two research questions: Why does the "germ cell" have a pivotal role in organization's transformation? and Which…

  16. Cell-fusion method to visualize interphase nuclear pore formation.

    Science.gov (United States)

    Maeshima, Kazuhiro; Funakoshi, Tomoko; Imamoto, Naoko

    2014-01-01

    In eukaryotic cells, the nucleus is a complex and sophisticated organelle that organizes genomic DNA to support essential cellular functions. The nuclear surface contains many nuclear pore complexes (NPCs), channels for macromolecular transport between the cytoplasm and nucleus. It is well known that the number of NPCs almost doubles during interphase in cycling cells. However, the mechanism of NPC formation is poorly understood, presumably because a practical system for analysis does not exist. The most difficult obstacle in the visualization of interphase NPC formation is that NPCs already exist after nuclear envelope formation, and these existing NPCs interfere with the observation of nascent NPCs. To overcome this obstacle, we developed a novel system using the cell-fusion technique (heterokaryon method), previously also used to analyze the shuttling of macromolecules between the cytoplasm and the nucleus, to visualize the newly synthesized interphase NPCs. In addition, we used a photobleaching approach that validated the cell-fusion method. We recently used these methods to demonstrate the role of cyclin-dependent protein kinases and of Pom121 in interphase NPC formation in cycling human cells. Here, we describe the details of the cell-fusion approach and compare the system with other NPC formation visualization methods. Copyright © 2014 Elsevier Inc. All rights reserved.

  17. Changes in numbers and types of mast cell colony-forming cells in the peritoneal cavity of mice after injection of distilled water: evidence that mast cells suppress differentiation of bone marrow-derived precursors

    International Nuclear Information System (INIS)

    Kanakura, Y.; Kuriu, A.; Waki, N.; Nakano, T.; Asai, H.; Yonezawa, T.; Kitamura, Y.

    1988-01-01

    Two different types of cells in the peritoneal cavity of mice produce mast cell colonies in methylcellulose. Large mast cell colonies are produced by bone marrow-derived precursors resembling lymphoid cells by light microscopy (L-CFU-Mast), whereas medium and small mast cell colonies are produced by morphologically identifiable mast cells (M-CFU-Mast and S-CFU-Mast, respectively). In the present study we eradicated peritoneal mast cells by intraperitoneal (IP) injection of distilled water. The regeneration process was investigated to clarify the relationship between L-CFU-Mast, M-CFU-Mast, and S-CFU-Mast. After injection of distilled water, M-CFU-Mast and S-CFU-Mast disappeared, but L-CFU-Mast increased, and then M-CFU-Mast and S-CFU-Mast appeared, suggesting the presence of a hierarchic relationship. When purified peritoneal mast cells were injected two days after the water injection, the L-CFU-Mast did not increase. In the peritoneal cavity of WBB6F1-+/+ mice that had been lethally irradiated and rescued by bone marrow cells of C57BL/6-bgJ/bgJ (beige, Chediak-Higashi syndrome) mice, L-CFU-Mast were of bgJ/bgJ type, but M-CFU-Mast and S-CFU-Mast were of +/+ type. The injection of distilled water to the radiation chimeras resulted in the development of bgJ/bgJ-type M-CFU-Mast and then S-CFU-Mast. The presence of mast cells appeared to suppress the recruitment of L-CFU-Mast from the bloodstream and to inhibit the differentiation of L-CFU-Mast to M-CFU-Mast

  18. Changes in numbers and types of mast cell colony-forming cells in the peritoneal cavity of mice after injection of distilled water: evidence that mast cells suppress differentiation of bone marrow-derived precursors

    Energy Technology Data Exchange (ETDEWEB)

    Kanakura, Y.; Kuriu, A.; Waki, N.; Nakano, T.; Asai, H.; Yonezawa, T.; Kitamura, Y.

    1988-03-01

    Two different types of cells in the peritoneal cavity of mice produce mast cell colonies in methylcellulose. Large mast cell colonies are produced by bone marrow-derived precursors resembling lymphoid cells by light microscopy (L-CFU-Mast), whereas medium and small mast cell colonies are produced by morphologically identifiable mast cells (M-CFU-Mast and S-CFU-Mast, respectively). In the present study we eradicated peritoneal mast cells by intraperitoneal (IP) injection of distilled water. The regeneration process was investigated to clarify the relationship between L-CFU-Mast, M-CFU-Mast, and S-CFU-Mast. After injection of distilled water, M-CFU-Mast and S-CFU-Mast disappeared, but L-CFU-Mast increased, and then M-CFU-Mast and S-CFU-Mast appeared, suggesting the presence of a hierarchic relationship. When purified peritoneal mast cells were injected two days after the water injection, the L-CFU-Mast did not increase. In the peritoneal cavity of WBB6F1-+/+ mice that had been lethally irradiated and rescued by bone marrow cells of C57BL/6-bgJ/bgJ (beige, Chediak-Higashi syndrome) mice, L-CFU-Mast were of bgJ/bgJ type, but M-CFU-Mast and S-CFU-Mast were of +/+ type. The injection of distilled water to the radiation chimeras resulted in the development of bgJ/bgJ-type M-CFU-Mast and then S-CFU-Mast. The presence of mast cells appeared to suppress the recruitment of L-CFU-Mast from the bloodstream and to inhibit the differentiation of L-CFU-Mast to M-CFU-Mast.

  19. Enhancement of the grafting efficiency of transplanted marrow cells by preincubation with interleukin-3 and granulocyte-macrophage colony-stimulating factor

    International Nuclear Information System (INIS)

    Tavassoli, M.; Konno, M.; Shiota, Y.; Omoto, E.; Minguell, J.J.; Zanjani, E.D.

    1991-01-01

    To improve the grafting efficiency of transplanted murine hematopoietic progenitors, we briefly preincubated mouse bone marrow cells with interleukin-3 (IL-3) or granulocyte-macrophage colony-stimulating factor (GM-CSF) ex vivo before their transplantation into irradiated recipients. This treatment was translated into an increase in the seeding efficiency of colony-forming unit-spleen (CFU-S) and CFU-GM after transplantation. Not only was the concentration of CFU-S in the tibia increased 2 and 24 hours after transplantation, but the total cell number and CFU-S and CFU-GM concentrations were persistently higher in IL-3- and GM-CSF-treated groups 1 to 3 weeks after transplantation. In addition, the survival of animals as a function of transplanted cell number was persistently higher in IL-3- and GM-CSF-treated groups compared with controls. The data indicate that the pretreatment of marrow cells with IL-3 and GM-CSF before transplantation increases the seeding efficiency of hematopoietic stem cells and probably other progenitor cells after transplantation. This increased efficiency may be mediated by upward modulation of homing receptors. Therefore, ex vivo preincubation of donor marrow cells with IL-3 and GM-CSF may be a useful tactic in bone marrow transplantation

  20. Enhancement of the grafting efficiency of transplanted marrow cells by preincubation with interleukin-3 and granulocyte-macrophage colony-stimulating factor

    Energy Technology Data Exchange (ETDEWEB)

    Tavassoli, M.; Konno, M.; Shiota, Y.; Omoto, E.; Minguell, J.J.; Zanjani, E.D.

    1991-04-01

    To improve the grafting efficiency of transplanted murine hematopoietic progenitors, we briefly preincubated mouse bone marrow cells with interleukin-3 (IL-3) or granulocyte-macrophage colony-stimulating factor (GM-CSF) ex vivo before their transplantation into irradiated recipients. This treatment was translated into an increase in the seeding efficiency of colony-forming unit-spleen (CFU-S) and CFU-GM after transplantation. Not only was the concentration of CFU-S in the tibia increased 2 and 24 hours after transplantation, but the total cell number and CFU-S and CFU-GM concentrations were persistently higher in IL-3- and GM-CSF-treated groups 1 to 3 weeks after transplantation. In addition, the survival of animals as a function of transplanted cell number was persistently higher in IL-3- and GM-CSF-treated groups compared with controls. The data indicate that the pretreatment of marrow cells with IL-3 and GM-CSF before transplantation increases the seeding efficiency of hematopoietic stem cells and probably other progenitor cells after transplantation. This increased efficiency may be mediated by upward modulation of homing receptors. Therefore, ex vivo preincubation of donor marrow cells with IL-3 and GM-CSF may be a useful tactic in bone marrow transplantation.

  1. Inhibition of miR-155, a therapeutic target for breast cancer, prevented in cancer stem cell formation.

    Science.gov (United States)

    Zuo, Jiangcheng; Yu, Yalan; Zhu, Man; Jing, Wei; Yu, Mingxia; Chai, Hongyan; Liang, Chunzi; Tu, Jiancheng

    2018-02-06

    Breast cancer is a common cancer in women of worldwide. Cancer cells with stem-like properties played important roles in breast cancer, such as relapse, metastasis and treatment resistance. Micro-RNA-155 (miR-155) is a well-known oncogenic miRNA overexpressed in many human cancers. The expression levels of miR-155 in 38 pairs of cancer tissues and adjacent normal tissues from breast cancer patients were detected using quantitative real-time PCR. The invasive cell line MDA-MB-231 was used to quantify the expression of miR-155 by tumor-sphere forming experiment. Soft agar colony formation assay and tumor xenografts was used to explore whether the inhibition of miR-155 could reduce proliferation of cancer cells in vivo and vitro. In the study, we found miR-155 was upregulated in BC. Soft agar colony formation assay and tumor xenografts showed inhibition of miR-155 could significantly reduce proliferation of cancer cells in vivo and vitro, which confirmed that miR-155 is an effective therapeutic target of breast cancer. Sphere-forming experiment showed that overexpression of miR-155 significantly correlated with stem-like properties. Expressions of ABCG2, CD44 and CD90 were repressed by inhibition of miR-155, but CD24 was promoted. Interestingly, inhibition of miR-155 rendered MDA-MB-231 cells more sensitive to Doxorubicinol, which resulted in an increase of inhibition rate from 20.23% to 68.72%. Expression of miR-155 not only was a therapeutic target but also was associated with cancer stem cell formation and Doxorubicinol sensitivity. Our results underscore the importance of miR-155 as a therapeutic target and combination of Doxorubicinol and miR-155-silencing would be a potential way to cure breast cancer.

  2. Cell Competition Drives the Formation of Metastatic Tumors in a Drosophila Model of Epithelial Tumor Formation

    DEFF Research Database (Denmark)

    Eichenlaub, Teresa; Cohen, Stephen M; Herranz, Héctor

    2016-01-01

    Cell competition is a homeostatic process in which proliferating cells compete for survival. Elimination of otherwise normal healthy cells through competition is important during development and has recently been shown to contribute to maintaining tissue health during organismal aging. The mechan......Cell competition is a homeostatic process in which proliferating cells compete for survival. Elimination of otherwise normal healthy cells through competition is important during development and has recently been shown to contribute to maintaining tissue health during organismal aging....... The mechanisms that allow for ongoing cell competition during adult life could, in principle, contribute to tumorigenesis. However, direct evidence supporting this hypothesis has been lacking. Here, we provide evidence that cell competition drives tumor formation in a Drosophila model of epithelial cancer. Cells...... of the Septin family protein Peanut. Cytokinesis failure due to downregulation of Peanut is required for tumorigenesis. This study provides evidence that the cellular mechanisms that drive cell competition during normal tissue growth can be co-opted to drive tumor formation and metastasis. Analogous mechanisms...

  3. Pulp stem cells: implication in reparative dentin formation.

    Science.gov (United States)

    Dimitrova-Nakov, Sasha; Baudry, Anne; Harichane, Yassine; Kellermann, Odile; Goldberg, Michel

    2014-04-01

    Many dental pulp stem cells are neural crest derivatives essential for lifelong maintenance of tooth functions and homeostasis as well as tooth repair. These cells may be directly implicated in the healing process or indirectly involved in cell-to-cell diffusion of paracrine messages to resident (pulpoblasts) or nonresident cells (migrating mesenchymal cells). The identity of the pulp progenitors and the mechanisms sustaining their regenerative capacity remain largely unknown. Taking advantage of the A4 cell line, a multipotent stem cell derived from the molar pulp of mouse embryo, we investigated the capacity of these pulp-derived precursors to induce in vivo the formation of a reparative dentin-like structure upon implantation within the pulp of a rodent incisor or a first maxillary molar after surgical exposure. One month after the pulp injury alone, a nonmineralized fibrous matrix filled the mesial part of the coronal pulp chamber. Upon A4 cell implantation, a mineralized osteodentin was formed in the implantation site without affecting the structure and vitality of the residual pulp in the central and distal parts of the pulp chamber. These results show that dental pulp stem cells can induce the formation of reparative dentin and therefore constitute a useful tool for pulp therapies. Finally, reparative dentin was also built up when A4 progenitors were performed by alginate beads, suggesting that alginate is a suitable carrier for cell implantation in teeth. Copyright © 2014 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  4. CARBOHYDRATE-BASED CELL ADHESION: ANALYSIS OF SPHEROID FORMATION

    Directory of Open Access Journals (Sweden)

    Marco Antonio Vieira Macedo Grinet

    2017-04-01

    Full Text Available Carbohydrates are vast constituents of cell surfaces and in many systems where cell adhesion plays a critical role, carbohydrate binding proteins have been shown to bind to cell surface carbohydrates and participate in cell-cell interactions. Jurkat cells are suspension cells that grow in clumps and have 20.7 (± 2.2 hours of population doubling time (PDT. In this experiment, Jurkat cells are studied to compare the effects of wheat germ agglutinin (WGA lectin, and Maackia amurensis (MAA lectin, for clumping and spheroid formation studies, as well as carbohydrate analog solutions in ethanol (C2H6O Ac4ManNAc, and Ac5ManNTGc for concentration effect studies.

  5. Clinical outcome after stem cell mobilization with granulocyte-colony-stimulating factor after acute ST-elevation myocardial infarction:

    DEFF Research Database (Denmark)

    Ripa, Rasmus S; Jørgensen, Erik; Kastrup, Jens

    2013-01-01

    Background. Granulocyte-colony-stimulating factor (G-CSF) has been investigated in trials aiming to promote recovery of myocardial function after myocardial infarction. Long-term safety-data have never been reported. A few studies indicated an increased risk of in-stent re-stenosis. We aimed...

  6. Direct anti-inflammatory effects of granulocyte colony-stimulating factor (G-CSF) on activation and functional properties of human T cell subpopulations in vitro.

    Science.gov (United States)

    Malashchenko, Vladimir Vladimirovich; Meniailo, Maxsim Evgenievich; Shmarov, Viacheslav Anatolievich; Gazatova, Natalia Dinislamovna; Melashchenko, Olga Borisovna; Goncharov, Andrei Gennadievich; Seledtsova, Galina Victorovna; Seledtsov, Victor Ivanovich

    2018-03-01

    We investigated the direct effects of human granulocyte colony-stimulating factor (G-CSF) on functionality of human T-cell subsets. CD3 + T-lymphocytes were isolated from blood of healthy donors by positive magnetic separation. T cell activation with particles conjugated with antibodies (Abs) to human CD3, CD28 and CD2 molecules increased the proportion of cells expressing G-CSF receptor (G-CSFR, CD114) in all T cell subpopulations studied (CD45RA + /CD197 + naive T cells, CD45RA - /CD197 + central memory T cells, CD45RA - /CD197 - effector memory T cells and CD45RA + /CD197 - terminally differentiated effector T cells). Upon T-cell activation in vitro, G-CSF (10.0 ng/ml) significantly and specifically enhanced the proportion of CD114 + T cells in central memory CD4 + T cell compartment. A dilution series of G-CSF (range, 0.1-10.0 ng/ml) was tested, with no effect on the expression of CD25 (interleukin-2 receptor α-chain) on activated T cells. Meanwhile, G-CSF treatment enhanced the proportion of CD38 + T cells in CD4 + naïve T cell, effector memory T cell and terminally differentiated effector T cell subsets, as well as in CD4 - central memory T cells and terminally differentiated effector T cells. G-CSF did not affect IL-2 production by T cells; relatively low concentrations of G-CSF down-regulated INF-γ production, while high concentrations of this cytokine up-regulated IL-4 production in activated T cells. The data obtained suggests that G-CSF could play a significant role both in preventing the development of excessive and potentially damaging inflammatory reactivity, and in constraining the expansion of potentially cytodestructive T cells. Copyright © 2018 Elsevier Inc. All rights reserved.

  7. Human disc cells in monolayer vs 3D culture: cell shape, division and matrix formation

    Directory of Open Access Journals (Sweden)

    Hanley Edward N

    2000-10-01

    Full Text Available Abstract Background The relationship between cell shape, proliferation, and extracellular matrix (ECM production, important aspects of cell behavior, is examined in a little-studied cell type, the human annulus cell from the intervertebral disc, during monolayer vs three-dimensional (3D culture. Results Three experimental studies showed that cells respond specifically to culture microenvironments by changes in cell shape, mitosis and ECM production: 1 Cell passages showed extensive immunohistochemical evidence of Type I and II collagens only in 3D culture. Chondroitin sulfate and keratan sulfate were abundant in both monolayer and 3D cultures. 2 Cells showed significantly greater proliferation in monolayer in the presence of platelet-derived growth factor compared to cells in 3D. 3 Cells on Matrigel™-coated monolayer substrates became rounded and formed nodular colonies, a finding absent during monolayer growth. Conclusions The cell's in vivo interactions with the ECM can regulate shape, gene expression and other cell functions. The shape of the annulus cell changes markedly during life: the young, healthy disc contains spindle shaped cells and abundant collagen. With aging and degeneration, many cells assume a strikingly different appearance, become rounded and are surrounded by unusual accumulations of ECM products. In vitro manipulation of disc cells provides an experimental window for testing how disc cells from given individuals respond when they are grown in environments which direct cells to have either spindle- or rounded-shapes. In vitro assessment of the response of such cells to platelet-derived growth factor and to Matrigel™ showed a continued influence of cell shape even in the presence of a growth factor stimulus. These findings contribute new information to the important issue of the influence of cell shape on cell behavior.

  8. Mesenchymal stem cells promote formation of colorectal tumors in mice.

    Science.gov (United States)

    Tsai, Kuo-Shu; Yang, Shung-Haur; Lei, Yen-Ping; Tsai, Chih-Chien; Chen, Hsin-Wei; Hsu, Chih-Yuan; Chen, Ling-Lan; Wang, Hsei-Wei; Miller, Stephanie A; Chiou, Shih-Hwa; Hung, Mien-Chie; Hung, Shih-Chieh

    2011-09-01

    Tumor-initiating cells are a subset of tumor cells with the ability to form new tumors; however, they account for less than 0.001% of the cells in colorectal or other types of tumors. Mesenchymal stem cells (MSCs) integrate into the colorectal tumor stroma; we investigated their involvement in tumor initiation. Human colorectal cancer cells, MSCs, and a mixture of both cell types were injected subcutaneously into immunodeficient mice. We compared the ability of each injection to form tumors and investigated the signaling pathway involved in tumor initiation. A small number (≤ 10) of unsorted, CD133⁻, CD166⁻, epithelial cell adhesion molecule⁻(EpCAM⁻), or CD133⁻/CD166⁻/EpCAM⁻ colorectal cancer cells, when mixed with otherwise nontumorigenic MSCs, formed tumors in mice. Secretion of interleukin (IL)-6 by MSCs increased the expression of CD133 and activation of Janus kinase 2-signal transducer and activator of transcription 3 (STAT3) in the cancer cells, and promoted sphere and tumor formation. An antibody against IL-6 or lentiviral-mediated transduction of an interfering RNA against IL-6 in MSCs or STAT3 in cancer cells prevented the ability of MSCs to promote sphere formation and tumor initiation. IL-6, secreted by MSCs, signals through STAT3 to increase the numbers of colorectal tumor-initiating cells and promote tumor formation. Reagents developed to disrupt this process might be developed to treat patients with colorectal cancer. Copyright © 2011 AGA Institute. Published by Elsevier Inc. All rights reserved.

  9. Persistence and dynamics of DNA damage signal amplification determined by microcolony formation and live-cell imaging

    International Nuclear Information System (INIS)

    Oka, Yasuyoshi; Yamauchi, Motohiro; Suzuki, Masatoshi; Yamashita, Shunichi; Suzuki, Keiji

    2011-01-01

    Cell cycle checkpoints are essential cellular process protecting the integrity of the genome from DNA damaging agents. In the present study, we developed a microcolony assay, in which normal human diploid fibroblast-like cells exposed to ionizing radiation, were plated onto coverslips at very low density (3 cells/cm 2 ). Cells were grown for up to 3 days, and phosphorylated ataxia-telangiectasia mutated (ATM) at Ser1981 and 53BP1 foci were analyzed as the markers for an amplified DNA damage signal. We observed a dose-dependent increase in the fraction of non-dividing cells, whose increase was compromised by knocking down p53 expression. While large persistent foci were predominantly formed in non-dividing cells, we observed some growing colonies that contained cells with large foci. As each microcolony was derived from a single cell, it appeared that some cells could proliferate with large foci. A live-imaging analysis using hTERT-immortalized normal human diploid cells transfected with the EGFP-tagged 53BP1 gene revealed that the formation of persistent large foci was highly dynamic. Delayed appearance and disappearance of large foci were frequently observed in exposed cells visualized 12-72 hours after X-irradiation. Thus, our results indicate that amplified DNA damage signal could be ignored, which may be explained in part by the dynamic nature of the amplification process. (author)

  10. Evaluation of a biosimilar granulocyte colony-stimulating factor (filgrastim XM02 for peripheral blood stem cell mobilization and transplantation: a single center experience in Japan

    Directory of Open Access Journals (Sweden)

    Yoshimura H

    2017-01-01

    Full Text Available Hideaki Yoshimura, Masaaki Hotta, Takahisa Nakanishi, Shinya Fujita, Aya Nakaya, Atsushi Satake, Tomoki Ito, Kazuyoshi Ishii, Shosaku Nomura First Department of Internal Medicine, Kansai Medical University, Hirakata, Osaka, Japan Background: Biosimilar granulocyte colony-stimulating factor (G-CSF has recently been introduced into clinical practice. G-CSFs are used to mobilize CD34+ cells and accelerate engraftment after transplantation. However, in Asia, particularly in Japan, data for peripheral blood stem cell (PBSC mobilization by this biosimilar G-CSF are currently lacking. Therefore, the clinical efficacy and safety of biosimilar G-CSF for hematopoietic stem cell transplantation needs to be evaluated in a Japanese context.Materials and methods: The subjects included two groups of patients with malignant lymphoma and multiple myeloma. All patients received chemotherapy priming for the mobilization of PBSCs. All patients were treated with chemotherapy followed by the administration of either the biosimilar G-CSF, filgrastim XM02 (FBNK, or the originators, filgrastim, or lenograstim.Results: There were no significant differences among FBNK, filgrastim, and lenograstim treatments in the numbers of CD34+ cells in harvested PBSCs, the scores for granulocyte/macrophage colony forming units, or for malignant lymphoma and multiple myeloma patients evaluated as separate or combined cohorts. In addition, there were no significant differences in safety, side effects, complications, or the time to engraftment after autologous hematopoietic stem cell transplantation.Conclusion: Biosimilar FBNK shows the same efficacy and safety as originator G-CSFs for facilitating bone marrow recovery in Japanese malignant lymphoma and multiple myeloma patients undergoing stem cell transplantation. In addition, it is less expensive than the originators, reducing hospitalization costs. Keywords: G-CSF, biosimilar, peripheral blood stem cell, hematological

  11. Subtotal ablation of parietal epithelial cells induces crescent formation.

    NARCIS (Netherlands)

    Sicking, E.M.; Fuss, A.; Uhlig, S.; Jirak, P.; Dijkman, H.; Wetzels, J.; Engel, D.R.; Urzynicok, T.; Heidenreich, S.; Kriz, W.; Kurts, C.; Ostendorf, T.; Floege, J.; Smeets, B.; Moeller, M.J.

    2012-01-01

    Parietal epithelial cells (PECs) of the renal glomerulus contribute to the formation of both cellular crescents in rapidly progressive GN and sclerotic lesions in FSGS. Subtotal transgenic ablation of podocytes induces FSGS but the effect of specific ablation of PECs is unknown. Here, we established

  12. Flexible PMP Approach for Large-Size Cell Formation

    NARCIS (Netherlands)

    Goldengorin, Boris; Krushinsky, Dmitry; Slomp, Jannes

    2012-01-01

    Lately, the problem of cell formation (CF) has gained a lot of attention in the industrial engineering literature. Since it was formulated (more than 50 years ago), the problem has incorporated additional industrial factors and constraints while its solution methods have been constantly improving in

  13. Neutrophil-induced transmigration of tumour cells treated with tumour-conditioned medium is facilitated by granulocyte-macrophage colony-stimulating factor.

    LENUS (Irish Health Repository)

    Wu, Q D

    2012-02-03

    OBJECTIVE: To investigate the effect of different cytokines that are present in tumour-conditioned medium on human neutrophil (PMN)-induced tumour cell transmigration. DESIGN: Laboratory study. SETTING: University hospital, Ireland. MATERIAL: Isolated human PMN and cultured human breast tumour cell line, MDA-MB-231. Interventions: Human PMN treated with either tumour-conditioned medium or different media neutralised with monoclonal antibodies (MoAb), and MDA-MB-231 cells were plated on macrovascular and microvascular endothelial monolayers in collagen-coated transwells to assess migration of tumour cells. MAIN OUTCOME MEASURES: Cytokines present in tumour-conditioned medium, PMN cytocidal function and receptor expression, and tumour cell transmigration. RESULTS: tumour-conditioned medium contained high concentrations of granulocyte-macrophage colony-stimulating factor (GM-CSF), vascular endothelial growth factor (VEGF), and interleukin 8 (IL-8), but not granulocyte colony-stimulating factor (G-CSF) and interleukin 3 (IL-3). Anti-GM-CSF MoAb significantly reduced PMN-induced transmigration of tumour cells treated with tumour-conditioned medium (p < 0.05), whereas anti-VEGF and anti-IL-8 MoAbs did not affect their migration. In addition, anti-GM-CSF MoAb, but not anti-VEGF or anti-IL-8 MoAb, reduced PMN CD11b and CD18 overexpression induced by tumour-conditioned medium (p < 0.05). CONCLUSION: These results indicate that the GM-CSF that is present in tumour-conditioned medium may be involved, at least in part, in alterations in PMN function mediated by the medium and subsequently PMN-induced transmigration of tumour cells.

  14. Characterization and clinical application of human CD34+ stem/progenitor cell populations mobilized into the blood by granulocyte colony-stimulating factor.

    Science.gov (United States)

    Gordon, Myrtle Y; Levicar, Natasa; Pai, Madhava; Bachellier, Philippe; Dimarakis, Ioannis; Al-Allaf, Faisal; M'Hamdi, Hanane; Thalji, Tamara; Welsh, Jonathan P; Marley, Stephen B; Davies, John; Dazzi, Francesco; Marelli-Berg, Federica; Tait, Paul; Playford, Raymond; Jiao, Long; Jensen, Steen; Nicholls, Joanna P; Ayav, Ahmet; Nohandani, Mahrokh; Farzaneh, Farzin; Gaken, Joop; Dodge, Rikke; Alison, Malcolm; Apperley, Jane F; Lechler, Robert; Habib, Nagy A

    2006-07-01

    A phase I study was performed to determine the safety and tolerability of injecting autologous CD34(+) cells into five patients with liver insufficiency. The study was based on the hypothesis that the CD34(+) cell population in granulocyte colony-stimulating factor (G-CSF)-mobilized blood contains a subpopulation of cells with the potential for regenerating damaged tissue. We separated a candidate CD34(+) stem cell population from the majority of the CD34(+) cells (99%) by adherence to tissue culture plastic. The adherent and nonadherent CD34(+) cells were distinct in morphology, immunophenotype, and gene expression profile. Reverse transcription-polymerase chain reaction-based gene expression analysis indicated that the adherent CD34(+) cells had the potential to express determinants consistent with liver, pancreas, heart, muscle, and nerve cell differentiation as well as hematopoiesis. Overall, the characteristics of the adherent CD34(+) cells identify them as a separate putative stem/progenitor cell population. In culture, they produced a population of cells exhibiting diverse morphologies and expressing genes corresponding to multiple tissue types. Encouraged by this evidence that the CD34(+) cell population contains cells with the potential to form hepatocyte-like cells, we gave G-CSF to five patients with liver insufficiency to mobilize their stem cells for collection by leukapheresis. Between 1 x 10(6) and 2 x 10(8) CD34(+) cells were injected into the portal vein (three patients) or hepatic artery (two patients). No complications or specific side effects related to the procedure were observed. Three of the five patients showed improvement in serum bilirubin and four of five in serum albumin. These observations warrant further clinical trials.

  15. High Expression of Colony-Stimulating Factor 1 Receptor Associates with Unfavorable Cancer-Specific Survival of Patients with Clear Cell Renal Cell Carcinoma.

    Science.gov (United States)

    Yang, Liu; Liu, Yidong; An, Huimin; Chang, Yuan; Zhang, Weijuan; Zhu, Yu; Xu, Le; Xu, Jiejie

    2016-03-01

    Colony-stimulating factor 1 receptor (CSF-1R), a single-pass type III transmembrane tyrosine-protein kinase, is mainly involved in inflammation and immune regulation to facilitate the progression of solid tumors. This study aimed to evaluate the impact of CSF-1R expression on clinical outcome of patients with clear cell renal cell carcinoma (ccRCC) after surgery. We retrospectively enrolled 268 patients with ccRCC undergoing nephrectomy between 2001 and 2004. Clinicopathologic features and cancer-specific survival (CSS) were collected. Western blot analysis was performed in the pairwise comparisons of CSF-1R expression in peritumor and tumor tissues of patients with ccRCC. Immunohistochemistry was conducted to determine CSF-1R expression level in tumor specimens. Survival analysis was performed by the Kaplan-Meier method. Cox regression models were used to evaluate the impact of prognostic factors on CSS. A concordance index was calculated to measure prognostic accuracy. A prognostic nomogram was constructed on the basis of the identified independent prognostic factors. CSF-1R expression in tumor tissues was higher than in peritumor tissues in 71.4% (5 of 7) patients. CSF-1R expression of tumor tissues was positively associated with metastasis, tumor, node, metastasis classification system (TNM) stage, Eastern Cooperative Oncology Group performance status score and poor CSS. CSF-1R expression was determined as an independent prognostic factor for CSS in patients with ccRCC. Furthermore, extension of the well-established prognostic models with CSF-1R expression presented significantly improved prognostic accuracy. An efficient prognostic nomogram was constructed on the basis of the independent prognostic factors. High CSF-1R expression is a potential independent adverse prognostic factor for CSS in patients with ccRCC.

  16. Growth of bacteria in 3-d colonies.

    Directory of Open Access Journals (Sweden)

    Xinxian Shao

    2017-07-01

    Full Text Available The dynamics of growth of bacterial populations has been extensively studied for planktonic cells in well-agitated liquid culture, in which all cells have equal access to nutrients. In the real world, bacteria are more likely to live in physically structured habitats as colonies, within which individual cells vary in their access to nutrients. The dynamics of bacterial growth in such conditions is poorly understood, and, unlike that for liquid culture, there is not a standard broadly used mathematical model for bacterial populations growing in colonies in three dimensions (3-d. By extending the classic Monod model of resource-limited population growth to allow for spatial heterogeneity in the bacterial access to nutrients, we develop a 3-d model of colonies, in which bacteria consume diffusing nutrients in their vicinity. By following the changes in density of E. coli in liquid and embedded in glucose-limited soft agar, we evaluate the fit of this model to experimental data. The model accounts for the experimentally observed presence of a sub-exponential, diffusion-limited growth regime in colonies, which is absent in liquid cultures. The model predicts and our experiments confirm that, as a consequence of inter-colony competition for the diffusing nutrients and of cell death, there is a non-monotonic relationship between total number of colonies within the habitat and the total number of individual cells in all of these colonies. This combined theoretical-experimental study reveals that, within 3-d colonies, E. coli cells are loosely packed, and colonies produce about 2.5 times as many cells as the liquid culture from the same amount of nutrients. We verify that this is because cells in liquid culture are larger than in colonies. Our model provides a baseline description of bacterial growth in 3-d, deviations from which can be used to identify phenotypic heterogeneities and inter-cellular interactions that further contribute to the structure of

  17. The colony-stimulating factor-1 (CSF-1 receptor sustains ERK1/2 activation and proliferation in breast cancer cell lines.

    Directory of Open Access Journals (Sweden)

    Andrea Morandi

    Full Text Available Breast cancer is the second leading cause of cancer-related deaths in western countries. Colony-Stimulating Factor-1 (CSF-1 and its receptor (CSF-1R regulate macrophage and osteoclast production, trophoblast implantation and mammary gland development. The expression of CSF-1R and/or CSF-1 strongly correlates with poor prognosis in several human epithelial tumors, including breast carcinomas. We demonstrate that CSF-1 and CSF-1R are expressed, although at different levels, in 16/17 breast cancer cell lines tested with no differences among molecular subtypes. The role of CSF-1/CSF-1R in the proliferation of breast cancer cells was then studied in MDAMB468 and SKBR3 cells belonging to different subtypes. CSF-1 administration induced ERK1/2 phosphorylation and enhanced cell proliferation in both cell lines. Furthermore, the inhibition of CSF-1/CSF-1R signaling, by CSF-1R siRNA or imatinib treatment, impaired CSF-1 induced ERK1/2 activation and cell proliferation. We also demonstrate that c-Jun, cyclin D1 and c-Myc, known for their involvement in cell proliferation, are downstream CSF-1R in breast cancer cells. The presence of a proliferative CSF-1/CSF-1R autocrine loop involving ERK1/2 was also found. The wide expression of the CSF-1/CSF-1R pair across breast cancer cell subtypes supports CSF-1/CSF-1R targeting in breast cancer therapy.

  18. Just-in-time rescue plerixafor in combination with chemotherapy and granulocyte-colony stimulating factor for peripheral blood progenitor cell mobilization.

    Science.gov (United States)

    Smith, Veronica R; Popat, Uday; Ciurea, Stefan; Nieto, Yago; Anderlini, Paolo; Rondon, Gabriela; Alousi, Amin; Qazilbash, Muzaffar; Kebriaei, Partow; Khouri, Issa; de Lima, Marcos; Champlin, Richard; Hosing, Chitra

    2013-09-01

    Plerixafor, a recently approved peripheral blood progenitor cell mobilizing agent, is often added to granulocyte-colony stimulating factor (G-CSF) to mobilize peripheral blood progenitor cells in patients with lymphoma or myeloma who cannot mobilize enough CD34+ cells with G-CSF alone to undergo autologous stem cell transplantation. However, data are lacking regarding the feasibility and efficacy of just-in-time plerixafor in combination with chemotherapy and G-CSF. We reviewed the peripheral blood stem cell collection data of 38 consecutive patients with lymphoma (Hodgkin's and non-Hodgkin's) and multiple myeloma who underwent chemomobilization and high-dose G-CSF and just-in-time plerixafor to evaluate the efficacy of this treatment combination. All patients with multiple myeloma and all but one patient with lymphoma collected the minimum required number of CD34+ cells to proceed with autologous stem cell transplantation (>2 × 10(6) /kg of body weight). The median CD34+ cell dose collected in patients with non-Hodgkin lymphoma was 4.93 × 10(6) /kg of body weight. The median CD34+ cell dose collected for patients with multiple myeloma was 8.81 × 10(6) /kg of body weight. Plerixafor was well tolerated; no grade 2 or higher non-hematologic toxic effects were observed. Copyright © 2013 Wiley Periodicals, Inc.

  19. Vaccination with Irradiated Tumor Cells Engineered to Secrete Murine Granulocyte-Macrophage Colony-Stimulating Factor Stimulates Potent, Specific, and Long-Lasting Anti-Tumor Immunity

    Science.gov (United States)

    Dranoff, Glenn; Jaffee, Elizabeth; Lazenby, Audrey; Golumbek, Paul; Levitsky, Hyam; Brose, Katja; Jackson, Valerie; Hamada, Hirofumi; Pardoll, Drew; Mulligan, Richard C.

    1993-04-01

    To compare the ability of different cytokines and other molecules to enhance the immunogenicity of tumor cells, we generated 10 retroviruses encoding potential immunomodulators and studied the vaccination properties of murine tumor cells transduced by the viruses. Using a B16 melanoma model, in which irradiated tumor cells alone do not stimulate significant anti-tumor immunity, we found that irradiated tumor cells expressing murine granulocyte-macrophage colony-stimulating factor (GM-CSF) stimulated potent, long-lasting, and specific anti-tumor immunity, requiring both CD4^+ and CD8^+ cells. Irradiated cells expressing interleukins 4 and 6 also stimulated detectable, but weaker, activity. In contrast to the B16 system, we found that in a number of other tumor models, the levels of anti-tumor immunity reported previously in cytokine gene transfer studies involving live, transduced cells could be achieved through the use of irradiated cells alone. Nevertheless, manipulation of the vaccine or challenge doses made it possible to demonstrate the activity of murine GM-CSF in those systems as well. Overall, our results have important implications for the clinical use of genetically modified tumor cells as therapeutic cancer vaccines.

  20. Pretransplant mobilization with granulocyte colony-stimulating factor improves B-cell reconstitution by lentiviral vector gene therapy in SCID-X1 mice.

    Science.gov (United States)

    Huston, Marshall W; Riegman, Adriaan R A; Yadak, Rana; van Helsdingen, Yvette; de Boer, Helen; van Til, Niek P; Wagemaker, Gerard

    2014-10-01

    Hematopoietic stem cell (HSC) gene therapy is a demonstrated effective treatment for X-linked severe combined immunodeficiency (SCID-X1), but B-cell reconstitution and function has been deficient in many of the gene therapy treated patients. Cytoreductive preconditioning is known to improve HSC engraftment, but in general it is not considered for SCID-X1 since the poor health of most of these patients at diagnosis and the risk of toxicity preclude the conditioning used in standard bone marrow stem cell transplantation. We hypothesized that mobilization of HSC by granulocyte colony-stimulating factor (G-CSF) should create temporary space in bone marrow niches to improve engraftment and thereby B-cell reconstitution. In the present pilot study supplementing our earlier preclinical evaluation (Huston et al., 2011), Il2rg(-/-) mice pretreated with G-CSF were transplanted with wild-type lineage negative (Lin(-)) cells or Il2rg(-/-) Lin(-) cells transduced with therapeutic IL2RG lentiviral vectors. Mice were monitored for reconstitution of lymphocyte populations, level of donor cell chimerism, and antibody responses as compared to 2 Gy total body irradiation (TBI), previously found effective in promoting B-cell reconstitution. The results demonstrate that G-CSF promotes B-cell reconstitution similar to low-dose TBI and provides proof of principle for an alternative approach to improve efficacy of gene therapy in SCID patients without adverse effects associated with cytoreductive conditioning.

  1. Yeast cell wall chitin reduces wine haze formation.

    Science.gov (United States)

    Ndlovu, Thulile; Divol, Benoit; Bauer, Florian F

    2018-04-27

    Protein haze formation in bottled wines is a significant concern for the global wine industry and wine clarification before bottling is therefore a common but expensive practice. Previous studies have shown that wine yeast strains can reduce haze formation through the secretion of certain mannoproteins, but it has been suggested that other yeast-dependent haze protective mechanisms exist. On the other hand, addition of chitin has been shown to reduce haze formation, likely because grape chitinases have been shown to be the major contributors to haze. In this study, Chardonnay grape must fermented by various yeast strains resulted in wines with different protein haze levels indicating differences in haze protective capacities of the strains. The cell wall chitin levels of these strains were determined, and a strong correlation between cell wall chitin levels and haze protection capability was observed. To further evaluate the mechanism of haze protection, Escherichia coli -produced GFP-tagged grape chitinase was shown to bind efficiently to yeast cell walls in a cell wall chitin concentration-dependent manner, while commercial chitinase was removed from synthetic wine in quantities also correlated with the cell wall chitin levels of the strains. Our findings suggest a new mechanism of reducing wine haze, and propose a strategy for optimizing wine yeast strains to improve wine clarification. Importance In this study, we establish a new mechanism by which wine yeast strains can impact on the protein haze formation of wines, and demonstrate that yeast cell wall chitin binds grape chitinase in a chitin-concentration dependent manner. We also show that yeast can remove this haze-forming protein from wine. Chitin has in the past been shown to efficiently reduce wine haze formation when added to the wine in high concentration as a clarifying agent. Our data suggest that the selection of yeast strains with high levels of cell wall chitin can reduce protein haze. We also

  2. Adenosine formation in contracting primary rat skeletal muscle cells and endothelial cells in culture

    DEFF Research Database (Denmark)

    Hellsten, Ylva; Frandsen, Ulrik

    1997-01-01

    1. The present study examined the capacity for adenosine formation, uptake and metabolism in contracting primary rat muscle cells and in microvascular endothelial cells in culture. 2. Strong and moderate electrical simulation of skeletal muscle cells led to a significantly greater increase...

  3. Endothelial cell confluence regulates Weibel-Palade body formation.

    Science.gov (United States)

    Howell, Gareth J; Herbert, Shane P; Smith, Jennifer M; Mittar, Shweta; Ewan, Lorna C; Mohammed, Mudassir; Hunter, Alison R; Simpson, Nigel; Turner, Anthony J; Zachary, Ian; Walker, John H; Ponnambalam, Sreenivasan

    2004-01-01

    Secretory granules called Weibel-Palade bodies (WPBs) containing Von Willebrand factor (VWF) are characteristic of the mammalian endothelium. We hypothesized that vascular-specific antigens such as VWF are linked to endothelial identity and proliferation in vitro. To test this idea, the cellular accumulation of VWF in WPBs was monitored as a function of cell proliferation, confluence and passage number in human umbilical vein endothelial cells (HUVECs). We found that as passage number increased the percentage of cells containing VWF in WPBs was reduced significantly, whilst the protein was still detected within the secretory pathway at all times. However, the endothelial-specific marker protein, PECAM-1, is present on all cells even when WPBs are absent, indicating partial maintenance of endothelial identity. Biochemical studies show that a significant pool of immature pro-VWF can be detected in sub-confluent HUVECs; however, a larger pool of mature, processed VWF is detected in confluent cells. Newly synthesized VWF must thus be differentially sorted and packaged along the secretory pathway in semi-confluent versus confluent endothelial cells. Our studies thus show that WPB formation is linked to the formation of a confluent endothelial monolayer.

  4. Human progenitor cells rapidly mobilized by AMD3100 repopulate NOD/SCID mice with increased frequency in comparison to cells from the same donor mobilized by granulocyte colony stimulating factor

    DEFF Research Database (Denmark)

    Hess, David A; Bonde, Jesper; Craft, Timothy P

    2007-01-01

    AMD3100 inhibits the interaction between SDF-1 and CXCR4, and rapidly mobilizes hematopoietic progenitors for clinical transplantation. However, the repopulating function of human cells mobilized with AMD3100 has not been characterized in comparison to cells mobilized with granulocyte-colony stim......AMD3100 inhibits the interaction between SDF-1 and CXCR4, and rapidly mobilizes hematopoietic progenitors for clinical transplantation. However, the repopulating function of human cells mobilized with AMD3100 has not been characterized in comparison to cells mobilized with granulocyte...

  5. Prevention of Tracheal High-Dose Tolerance Induction by Granulocyte-Macrophage Colony Stimulating Factor- Dependent Restoration of Antigen-Presenting Cell Function

    Directory of Open Access Journals (Sweden)

    Kanna Haneda

    2000-01-01

    Full Text Available The intrusion of airborne allergens into airways elicits eosinophilic inflammation, as represented by bronchial asthma. It has been shown that excessive amounts of allergen in murine trachea lead to an unexpected evasion of deleterious eosinophilic inflammation by inducing T cell tolerance. In the present study, the mechanisms of tracheal high-dose tolerance are examined with regard to accessory cell functions and the effects of pro-inflammatory cytokines on tolerance. Antigen-induced tracheal eosinophilia was suppressed on instillation of high doses of antigen into the trachea, while concurrent instillation of granulocyte-macrophage colony stimulating factor (GM-CSF with the antigen restored the diminished responses. The restoration of eosinophilic infiltration by GM-CSF occurred in parallel with an increase in interleukin (IL-4 production by CD4+ T cells from the mediastinal lymph nodes. This was found to reflect the empowerment of antigen-presenting cells by GM-CSF, because the impaired ability of Ia+ cells from the tolerant mice to stimulate IL-4-producing T cells is restored by GM-CSF administration. The prevention of tolerance by up-regulating accessory cell functions is a feature unique to GM-CSF, because another pro-inflammatory cytokine, IL-iβ, failed to empower antigen-presenting cells. Thus, besides the induction of transforming growth factor-β-secreting CD4+ T cells, high-dose tolerance in the trachea includes an impairment of the accessory cell functions that support IL-4 production from T cells, which was reversed by GM-CSF. This report is the first demonstration that GM-CSF breaks the T cell tolerance of IL-4-producing T helper cells.

  6. RNA-binding IMPs promote cell adhesion and invadopodia formation

    DEFF Research Database (Denmark)

    Vikesaa, Jonas; Hansen, Thomas V O; Jønson, Lars

    2006-01-01

    Oncofetal RNA-binding IMPs have been implicated in mRNA localization, nuclear export, turnover and translational control. To depict the cellular actions of IMPs, we performed a loss-of-function analysis, which showed that IMPs are necessary for proper cell adhesion, cytoplasmic spreading......-mediated invadopodia formation. Taken together, our results indicate that RNA-binding proteins exert profound effects on cellular adhesion and invasion during development and cancer formation....... and invadopodia formation. Loss of IMPs was associated with a coordinate downregulation of mRNAs encoding extracellular matrix and adhesion proteins. The transcripts were present in IMP RNP granules, implying that IMPs were directly involved in the post-transcriptional control of the transcripts. In particular...

  7. Comparison of Teratoma Formation between Embryonic Stem Cells and Parthenogenetic Embryonic Stem Cells by Molecular Imaging

    Directory of Open Access Journals (Sweden)

    Hongyan Tao

    2018-01-01

    Full Text Available With their properties of self-renewal and differentiation, embryonic stem (ES cells hold great promises for regenerative therapy. However, teratoma formation and ethical concerns of ES cells may restrict their potential clinical applications. Currently, parthenogenetic embryonic stem (pES cells have attracted the interest of researchers for its self-renewing and pluripotent differentiation while eliciting less ethic concerns. In this study, we established a model with ES and pES cells both stably transfected with a double-fusion reporter gene containing renilla luciferase (Rluc and red fluorescent protein (RFP to analyze the mechanisms of teratoma formation. Transgenic Vegfr2-luc mouse, which expresses firefly luciferase (Fluc under the promoter of vascular endothelial growth factor receptor 2 (Vegfr2-luc, was used to trace the growth of new blood vessel recruited by transplanted cells. Bioluminescence imaging (BLI of Rluc/Fluc provides an effective tool in estimating the growth and angiogenesis of teratoma in vivo. We found that the tumorigenesis and angiogenesis capacity of ES cells were higher than those of pES cells, in which VEGF/VEGFR2 signal pathway plays an important role. In conclusion, pES cells have the decreased potential of teratoma formation but meanwhile have similar differentiating capacity compared with ES cells. These data demonstrate that pES cells provide an alternative source for ES cells with the risk reduction of teratoma formation and without ethical controversy.

  8. Aroma formation by immobilized yeast cells in fermentation processes.

    Science.gov (United States)

    Nedović, V; Gibson, B; Mantzouridou, T F; Bugarski, B; Djordjević, V; Kalušević, A; Paraskevopoulou, A; Sandell, M; Šmogrovičová, D; Yilmaztekin, M

    2015-01-01

    Immobilized cell technology has shown a significant promotional effect on the fermentation of alcoholic beverages such as beer, wine and cider. However, genetic, morphological and physiological alterations occurring in immobilized yeast cells impact on aroma formation during fermentation processes. The focus of this review is exploitation of existing knowledge on the biochemistry and the biological role of flavour production in yeast for the biotechnological production of aroma compounds of industrial importance, by means of immobilized yeast. Various types of carrier materials and immobilization methods proposed for application in beer, wine, fruit wine, cider and mead production are presented. Engineering aspects with special emphasis on immobilized cell bioreactor design, operation and scale-up potential are also discussed. Ultimately, examples of products with improved quality properties within the alcoholic beverages are addressed, together with identification and description of the future perspectives and scope for cell immobilization in fermentation processes. Copyright © 2014 John Wiley & Sons, Ltd.

  9. Macrophage Sortilin Promotes LDL Uptake, Foam Cell Formation, and Atherosclerosis

    Science.gov (United States)

    Patel, Kevin M.; Strong, Alanna; Tohyama, Junichiro; Jin, Xueting; Morales, Carlos R.; Billheimer, Jeffery; Millar, John; Kruth, Howard; Rader, Daniel J.

    2015-01-01

    Rationale Non-coding gene variants at the SORT1 locus are strongly associated with LDL-C levels as well as with coronary artery disease (CAD). SORT1 encodes a protein called sortilin, and hepatic sortilin modulates LDL metabolism by targeting apoB-containing lipoproteins to the lysosome. Sortilin is also expressed in macrophages, but its role in macrophage uptake of LDL and in atherosclerosis independent of plasma LDL-C levels is unknown. Objective To determine the effect of macrophage sortilin expression on LDL uptake, foam cell formation, and atherosclerosis. Methods and Results We crossed Sort1−/− mice onto a ‘humanized’ Apobec1−/−; hAPOB Tg background and determined that Sort1 deficiency on this background had no effect on plasma LDL-C levels but dramatically reduced atherosclerosis in the aorta and aortic root. In order to test whether this effect was a result of macrophage sortilin deficiency, we transplanted Sort1−/−;LDLR−/− or Sort1+/+;LDLR−/− bone marrow into Ldlr−/− mice and observed a similar reduction in atherosclerosis in mice lacking hematopoetic sortilin without an effect on plasma LDL-C levels. In an effort to determine the mechanism by which hematopoetic sortilin deficiency reduced atherosclerosis, we found no effect of sortilin deficiency on macrophage recruitment or LPS-induced cytokine release in vivo. In contrast, sortilin deficient macrophages had significantly reduced uptake of native LDL ex vivo and reduced foam cell formation in vivo, whereas sortilin overexpression in macrophages resulted in increased LDL uptake and foam cell formation. Conclusions Macrophage sortilin deficiency protects against atherosclerosis by reducing macrophage uptake of LDL. Sortilin-mediated uptake of native LDL into macrophages may be an important mechanism of foam cell formation and contributor to atherosclerosis development. PMID:25593281

  10. Blockade of mast cell activation reduces cutaneous scar formation.

    Directory of Open Access Journals (Sweden)

    Lin Chen

    Full Text Available Damage to the skin initiates a cascade of well-orchestrated events that ultimately leads to repair of the wound. The inflammatory response is key to wound healing both through preventing infection and stimulating proliferation and remodeling of the skin. Mast cells within the tissue are one of the first immune cells to respond to trauma, and upon activation they release pro-inflammatory molecules to initiate recruitment of leukocytes and promote a vascular response in the tissue. Additionally, mast cells stimulate collagen synthesis by dermal fibroblasts, suggesting they may also influence scar formation. To examine the contribution of mast cells in tissue repair, we determined the effects the mast cell inhibitor, disodium cromoglycate (DSCG, on several parameters of dermal repair including, inflammation, re-epithelialization, collagen fiber organization, collagen ultrastructure, scar width and wound breaking strength. Mice treated with DSCG had significantly reduced levels of the inflammatory cytokines IL-1α, IL-1β, and CXCL1. Although DSCG treatment reduced the production of inflammatory mediators, the rate of re-epithelialization was not affected. Compared to control, inhibition of mast cell activity caused a significant decrease in scar width along with accelerated collagen re-organization. Despite the reduced scar width, DSCG treatment did not affect the breaking strength of the healed tissue. Tryptase β1 exclusively produced by mast cells was found to increase significantly in the course of wound healing. However, DSCG treatment did not change its level in the wounds. These results indicate that blockade of mast cell activation reduces scar formation and inflammation without further weakening the healed wound.

  11. Proximal tubule-derived colony stimulating factor-1 mediates polarization of renal macrophages and dendritic cells, and recovery in acute kidney injury.

    Science.gov (United States)

    Wang, Yinqiu; Chang, Jian; Yao, Bing; Niu, Aolei; Kelly, Emily; Breeggemann, Matthew C; Abboud Werner, Sherry L; Harris, Raymond C; Zhang, Ming-Zhi

    2015-12-01

    Infiltrating cells play an important role in both the development of and recovery from acute kidney injury (AKI). Macrophages and renal dendritic cells are of particular interest because they can exhibit distinctly different functional phenotypes, broadly characterized as proinflammatory (M1) or tissue reparative (M2). Resident renal macrophages and dendritic cells participate in recovery from AKI in response to either ischemia/reperfusion or a model of selective proximal tubule injury induced by diphtheria-toxin-induced apoptosis in transgenic mice expressing the human diphtheria toxin receptor on proximal tubule cells. Colony-stimulating factor-1 (CSF-1) is an important factor mediating the recovery from AKI, and CSF-1 can stimulate macrophage and dendritic cell proliferation and polarization during the recovery phase of AKI. The kidney, and specifically the proximal tubule, is a major source of intrarenal CSF-1 production in response to AKI. We induced selective deletion of proximal tubule CSF-1 to determine its role in expansion and proliferation of renal macrophages and dendritic cells and in recovery from AKI. In both models of AKI, there was decreased M2 polarization, delayed functional and structural recovery, and increased tubulointerstitial fibrosis. Thus, intrarenal CSF-1 is an important mediator of macrophage/dendritic cell polarization and recovery from AKI.

  12. Activation of Natural Killer Cells in Patients with Chronic Bone and Joint Infection due to Staphylococci Expressing or Not the Small Colony Variant Phenotype

    Directory of Open Access Journals (Sweden)

    Sébastien Viel

    2014-01-01

    Full Text Available Chronic bone and joint infections (BJI are devastating diseases. Relapses are frequently observed, as some pathogens, especially staphylococci, can persist intracellularly by expressing a particular phenotype called small colony variant (SCV. As natural killer (NK cells are lymphocytes specialized in the killing of host cells infected by intracellular pathogens, we studied NK cells of patients with chronic BJI due to staphylococci expressing or not SCVs (10 patients in both groups. Controls were patients infected with other bacteria without detectable expression of SCVs, and healthy volunteers. NK cell phenotype was evaluated from PBMCs by flow cytometry. Degranulation capacity was evaluated after stimulation with K562 cells in vitro. We found that NK cells were activated in terms of CD69 expression, loss of CD16 and perforin, in all infected patients in comparison with healthy volunteers, independently of the SCV phenotype. Peripheral NK cells in patients with chronic BJI display signs of recent activation and degranulation in vivo in response to CD16-mediated signals, regardless of the type of bacteria involved. This could involve a universal capacity of isolates responsible for chronic BJI to produce undetectable SCVs in vivo, which might be a target of future intervention.

  13. Percutaneous implantation of peripheral blood mononuclear cells mobilized with granulocyte colony stimulating factor in osteoarthritis of the knee. First case reported in Cuba

    International Nuclear Information System (INIS)

    Baganet Cobas, Aymara Maria; Hernandez Ramirez, Porfirio; Fernandez Delgado, Norma

    2010-01-01

    The degenerative joint disease, also known as osteoarthrosis affects to 10% of elderlies aged 60. It is mainly characterized by pain in the involved joint, crepitation, morning stiff and a progressive limitation of movement of that joint leading to a partial or total wear of articular cartilage. The treatment of the knee osteoarthrosis is a great challenge. The recent advances in use of regenerative medicine suggest that adult stem cells could represent a promisor alternative in the treatment of this entity. In a female patient aged 61 presenting with knee osteoarthrosis authors placed a percutaneous implant of autologous mononuclear cells mobilized to peripheral blood by granulocyte colony-stimulating factor achieving a fast clinical and radiological improvement. This result suggests that the procedure used is a feasible, simple, safe and less expensive method for treatment of articular degenerative lesions

  14. T Cell factor 1 represses CD8+ effector T cell formation and function.

    Science.gov (United States)

    Tiemessen, Machteld M; Baert, Miranda R M; Kok, Lianne; van Eggermond, Marja C J A; van den Elsen, Peter J; Arens, Ramon; Staal, Frank J T

    2014-12-01

    The Wnt-responsive transcription factor T cell factor 1 (Tcf1) is well known for its role in thymic T cell development and the formation of memory CD8(+) T cells. However, its role in the initial phases of CD8(+) T effector cell formation has remained unexplored. We report that high levels of Wnt signaling and Tcf1 are operational in naive and memory CD8(+) T cells, whereas Wnt signaling and Tcf1 were low in effector CD8(+) T cells. CD8(+) T cells deficient in Tcf1 produce IFN-γ more rapidly, coinciding with increased demethylation of the IFN-γ enhancer and higher expression of the transcription factors Tbet and Blimp1. Moreover, virus-specific Tcf1(-/-) CD8(+) T cells show accelerated expansion in acute infection, which is associated with increased IFN-γ and TNF production and lower viral load. Genetic complementation experiments with various Tcf1 isoforms indicate that Tcf1 dosage and protein stability are critical in suppressing IFN-γ production. Isoforms lacking the β-catenin binding domain are equally effective in inhibiting CD8(+) effector T cell formation. Thus, Tcf1 functions as a repressor of CD8(+) effector T cell formation in a β-catenin/Wnt-independent manner. Copyright © 2014 by The American Association of Immunologists, Inc.

  15. CELL FORMATION IN GROUP TECHNOLOGY: A SIMILARITY ORDER CLUSTERING APPROACH

    Directory of Open Access Journals (Sweden)

    Godfrey C. Onwubolu

    2012-01-01

    Full Text Available Grouping parts into families which can be produced by a cluster of machine cells is the cornerstone of cellular manufacturing, which in turn is the building block for flexible manufacturing systems. Cellular manufacturing is a group technology (GT concept that has recently attracted the attention of manufacturing firms operating under jobshop environment to consider redesigning their manufacturing systems so as to take advantage of increased throughput, reduction in work-in-progress, set-up time, and lead times; leading to product quality and customer satisfaction. The paper presents a generalised approach for machine cell formation from a jobshop using similarity order clustering technique for preliminary cell grouping and considering machine utilisation for the design of nonintergrouping material handling using the single-pass heuristic. The work addresses the shortcomings of cellular manufacturing systems design and implementations which ignore machine utilisations, group sizes and intergroup moves.

  16. Evaluation of Dutch guideline for just-in-time addition of plerixafor to stem cell mobilization in patients who fail with granulocyte-colony-stimulating factor.

    Science.gov (United States)

    Bilgin, Yavuz M; Visser, Otto; Beckers, Erik A M; te Boome, Liane C J; Huisman, Cynthia; Ypma, Paula F; Croockewit, Alexandra J; Netelenbos, Tanja; Kramer, Ellen P A; de Greef, Georgine E

    2015-05-01

    Plerixafor in combination with granulocyte-colony-stimulating factor (G-CSF) is approved for the use of stem cell collection in patients who fail to mobilize on G-CSF. In 2009 the Stem Cell Working Party of the Dutch-Belgian Cooperative Trial group for Hematology Oncology (HOVON) composed a guideline for the use of plerixafor. According to this guideline it is recommended to add plerixafor to G-CSF in patients with circulating CD34+ cell counts of fewer than 20 × 10(6) /L on 2 consecutive days accompanied by increasing white blood cells. In this analysis we evaluated retrospectively the outcome of the use of this guideline in the Netherlands. In total 111 patients received plerixafor with a median one administration (range, one to four administrations). Of these patients 55.8% had non-Hodgkin lymphoma, 31.5% multiple myeloma, 8.1% Hodgkin lymphoma, and 4.5% nonhematologic malignancies. In 63.9% patients sufficient numbers of CD34+ cells were collected. In patients with multiple myeloma more successful mobilizations with plerixafor were observed compared to patients with non-Hodgkin lymphoma (71.4% vs. 61.3%). In patients with circulating CD34+ cell counts of at least 2.0 × 10(6) /L before administration of plerixafor a successful mobilization was achieved in 76.5%, and in the patients with very low (0-1 × 10(6) /L) circulating CD34+ cell counts the success rate was 44.2%. Application of the HOVON guideline on the just-in-time administration of plerixafor is effective for mobilization of hematopoietic stem cells in the majority of patients. Stem cell yield in patients with non-Hodgkin lymphoma was lower compared to patients with multiple myeloma. Also patients with very low circulating CD34+ cells before addition of plerixafor might benefit from this approach. © 2014 AABB.

  17. Homeostatic γδ T Cell Contents Are Preserved by Granulocyte Colony-Stimulating Factor Priming and Correlate with the Early Recovery of γδ T Cell Subsets after Haploidentical Hematopoietic Stem Cell Transplantation.

    Science.gov (United States)

    Bian, Zhilei; Xu, Lan-Ping; Fu, Qiang; Huo, Mingrui; Liu, Long; Zhao, Xiaosu; Huang, Xiao-Jun; Liu, Jiangying

    2018-02-01

    Emerging evidence from graft manipulations and immunotherapeutic treatments has highlighted a favorable effect of γδ T cells in the setting of allogeneic hematopoietic stem cell transplantation (alloHSCT). However, γδ T cell subsets and their distinct features in the allograft have not been characterized. Additionally, whether homeostatic γδ T cell fractions are influenced by treatment with granulocyte colony-stimulating factor (G-CSF) remains elusive. We initially compared the phenotypes of γδ T cell subsets, including CD27 + , CD27 - , Vδ1 + , Vδ2 + , Vδ1 + CD27 + , Vδ1 + CD27 - , Vδ2 + CD27 + , and Vδ2 + CD27 - cells, in the peripheral blood of 20 healthy donors before and after G-CSF mobilization. The effects of G-CSF on the cytokine production capacities of γδ T cell subsets were also detected. Moreover, the correlation between donor homeostatic γδ T cell content and the early recoveries of γδ T cell subgroups after haploidentical HSCT was investigated in 40 pairs of donors and recipients. We found that both the proportions and IFN-γ secretion capacities of peripheral γδ T cell subsets were preserved in G-CSF-primed grafts. Homeostatic Vδ1 and Vδ2 proportions of donors significantly correlated with the early recoveries of Vδ1 and Vδ2 cells after haploidentical HSCT. Interestingly, a higher day 30 Vδ1 concentration was associated with a lower incidence of cytomegalovirus reactivation in recipients. These results not only clarify the preservation of γδ T cell phenotypes and functional features by G-CSF mobilization but also suggest the importance of homeostatic γδ T cell content for immune recovery after alloHSCT. Copyright © 2017 The American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved.

  18. Clenbuterol Plus Granulocyte Colony-Stimulating Factor Regulates Stem/Progenitor Cell Mobilization and Exerts Beneficial Effect by Increasing Neovascularization in Rats With Heart Failure

    Science.gov (United States)

    TANAKA, TOSHIKAZU D.; LANCASTER, JORDAN J.; JUNEMAN, ELIZABETH; BAHL, JOSEPH J.; GOLDMAN, STEVEN

    2014-01-01

    Background Treatment of beta2-adrenergic receptor agonists with myeloid cytokines, such as granulocyte colony-stimulating factor (G-CSF) has been reported to enhance stem/progenitor cell mobilization and proliferation in ischemic myocardium. However, whether the combination therapy of G-CSF and clenbuterol (Clen) contributes to improved left ventricular (LV) function remains uncertain. We investigated whether this combination therapy induced bone marrow–derived stem/progenitor cell mobilization, neovascularization, and altered LV function after acute myocardial infarction (MI). Methods and Results Following MI, rats were treated with single Clen, high-dose Clen, and G-CSF + Clen. We evaluated LV function and remodeling with the use of echocardiography in addition to hemodynamics 3 weeks after MI. Treatment with G-CSF + Clen increased (P < .05), compared with no treatment, LV ejection fraction 46 ± 3% vs 34 ± 2%, LV dP/dt 5,789 ± 394 mm Hg vs 4,503 ± 283 mm Hg, and the percentage of circulating CD34+ cells, appearing to correlate with improvements in LV function. Conclusions Combination therapy improved LV function 3 weeks after MI, suggesting that G-CSF + Clen might augment stem/progenitor cell migration, contributing to tissue healing. These data raise the possibility that enhancing endogenous bone marrow–derived stem/progenitor cell mobilization may be a new treatment for ischemic heart failure after MI. PMID:23834926

  19. Inhibitory Effects of Salinomycin on Cell Survival, Colony Growth, Migration, and Invasion of Human Non-Small Cell Lung Cancer A549 and LNM35: Involvement of NAG-1.

    Directory of Open Access Journals (Sweden)

    Kholoud Arafat

    Full Text Available A major challenge for oncologists and pharmacologists is to develop more potent and less toxic drugs that will decrease the tumor growth and improve the survival of lung cancer patients. Salinomycin is a polyether antibiotic used to kill gram-positive bacteria including mycobacteria, protozoans such as plasmodium falciparum, and the parasites responsible for the poultry disease coccidiosis. This old agent is now a serious anti-cancer drug candidate that selectively inhibits the growth of cancer stem cells. We investigated the impact of salinomycin on survival, colony growth, migration and invasion of the differentiated human non-small cell lung cancer lines LNM35 and A549. Salinomycin caused concentration- and time-dependent reduction in viability of LNM35 and A549 cells through a caspase 3/7-associated cell death pathway. Similarly, salinomycin (2.5-5 µM for 7 days significantly decreased the growth of LNM35 and A549 colonies in soft agar. Metastasis is the main cause of death related to lung cancer. In this context, salinomycin induced a time- and concentration-dependent inhibition of cell migration and invasion. We also demonstrated for the first time that salinomycin induced a marked increase in the expression of the pro-apoptotic protein NAG-1 leading to the inhibition of lung cancer cell invasion but not cell survival. These findings identify salinomycin as a promising novel therapeutic agent for lung cancer.

  20. A microfluidic direct formate fuel cell on paper.

    Science.gov (United States)

    Copenhaver, Thomas S; Purohit, Krutarth H; Domalaon, Kryls; Pham, Linda; Burgess, Brianna J; Manorothkul, Natalie; Galvan, Vicente; Sotez, Samantha; Gomez, Frank A; Haan, John L

    2015-08-01

    We describe the first direct formate fuel cell on a paper microfluidic platform. In traditional membrane-less microfluidic fuel cells (MFCs), external pumping consumes power produced by the fuel cell in order to maintain co-laminar flow of the anode stream and oxidant stream to prevent mixing. However, in paper microfluidics, capillary action drives flow while minimizing stream mixing. In this work, we demonstrate a paper MFC that uses formate and hydrogen peroxide as the anode fuel and cathode oxidant, respectively. Using these materials we achieve a maximum power density of nearly 2.5 mW/mg Pd. In a series configuration, our MFC achieves an open circuit voltage just over 1 V, and in a parallel configuration, short circuit of 20 mA absolute current. We also demonstrate that the MFC does not require continuous flow of fuel and oxidant to produce power. We found that we can pre-saturate the materials on the paper, stop the electrolyte flow, and still produce approximately 0.5 V for 15 min. This type of paper MFC has potential applications in point-of-care diagnostic devices and other electrochemical sensors. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Recombinant human granulocyte colony-stimulating factor increases circulating CD34-postive cells in patients with AIDS

    DEFF Research Database (Denmark)

    Nielsen, S D; Dam-Larsen, S; Nielsen, C

    1997-01-01

    In a gene therapy-based treatment of AIDS, it would be desirable to have as many transduced target cells as possible. A limiting factor is the number of target cells. In this study, we investigated whether it was possible to increase the absolute number of one possible target cell, i.e., the circ...

  2. Molecular mechanisms for vascular development and secondary cell wall formation

    Directory of Open Access Journals (Sweden)

    Jung Hyun eYang

    2016-03-01

    Full Text Available Vascular tissues are important for transporting water and nutrients throughout the plant and as physical support of upright growth. The primary constituents of vascular tissues, xylem and phloem, are derived from the meristematic vascular procambium and cambium. Xylem cells develop secondary cell walls that form the largest part of plant lignocellulosic biomass that serve as a renewable feedstock for biofuel production. For the last decade, research on vascular development and secondary cell wall biosynthesis has seen rapid progress due to the importance of these processes to plant biology and to the biofuel industry. Plant hormones, transcriptional regulators and peptide signaling regulate procambium/cambium proliferation, vascular patterning, and xylem differentiation. Transcriptional regulatory pathways play a pivot role in secondary cell wall biosynthesis. Although most of these discoveries are derived from research in Arabidopsis, many genes have shown conserved functions in biofuel feedstock species. Here, we review the recent advances in our understanding of vascular development and secondary cell wall formation and discuss potential biotechnological uses.

  3. Colletotrichum higginsianum Mitogen-Activated Protein Kinase ChMK1: Role in Growth, Cell Wall Integrity, Colony Melanization and Pathogenicity

    Directory of Open Access Journals (Sweden)

    Wei Wei

    2016-08-01

    Full Text Available Colletotrichum higginsianum is an economically important pathogen that causes anthracnose disease in a wide range of cruciferous crops. To facilitate the efficient control of anthracnose disease, it will be important to understand the mechanism by which the cruciferous crops and C. higginsianum interact. A key step in understanding this interaction is characterizing the mitogen-activated protein kinases (MAPK signaling pathway of C. higginsianum. MAPK plays important roles in diverse physiological processes of multiple pathogens. In this study, a Fus3/Kss1-related MAPK gene, ChMK1, from C. higginsianum was analyzed. The results showed that the Fus3/Kss1-related MAPK ChMK1 plays a significant role in cell wall integrity. Targeted deletion of ChMK1 resulted in a hypersensitivity to cell wall inhibitors, reduced conidiation and albinistic colonies. Further, the deletion mutant was also unable to form melanized appressorium, a specialized infection structure that is necessary for successful infection. Therefore, the deletion mutant loses pathogenicity on A. thaliana leaves, demonstrating that ChMK1 plays an essential role in the early infection step. In addition, the ChMK1 deletion mutant showed an attenuated growth rate that is different from that of its homologue in C. lagenarium, indicating the diverse roles that Fus3/Kss1-related MAPKs plays in phytopathogenic fungi. Furthermore, the expression level of three melanin synthesis associated genes were clearly decreased in the albinistic ChMK1 mutant compared to that of the wild type strain, suggesting that ChMK1 is also required for colony melanization in C. higginsianum.

  4. Both systemic and local application of Granulocyte-colony stimulating factor (G-CSF is neuroprotective after retinal ganglion cell axotomy

    Directory of Open Access Journals (Sweden)

    Dietz Gunnar PH

    2009-05-01

    Full Text Available Abstract Background The hematopoietic Granulocyte-Colony Stimulating Factor (G-CSF plays a crucial role in controlling the number of neutrophil progenitor cells. Its function is mediated via the G-CSF receptor, which was recently found to be expressed also in the central nervous system. In addition, G-CSF provided neuroprotection in models of neuronal cell death. Here we used the retinal ganglion cell (RGC axotomy model to compare effects of local and systemic application of neuroprotective molecules. Results We found that the G-CSF receptor is robustly expressed by RGCs in vivo and in vitro. We thus evaluated G-CSF as a neuroprotectant for RGCs and found a dose-dependent neuroprotective effect of G-CSF on axotomized RGCs when given subcutaneously. As stem stell mobilization had previously been discussed as a possible contributor to the neuroprotective effects of G-CSF, we compared the local treatment of RGCs by injection of G-CSF into the vitreous body with systemic delivery by subcutaneous application. Both routes of application reduced retinal ganglion cell death to a comparable extent. Moreover, G-CSF enhanced the survival of immunopurified RGCs in vitro. Conclusion We thus show that G-CSF neuroprotection is at least partially independent of potential systemic effects and provide further evidence that the clinically applicable G-CSF could become a treatment option for both neurodegenerative diseases and glaucoma.

  5. Role of plerixafor in autologous stem cell mobilization with vinorelbine chemotherapy and granulocyte-colony stimulating factor in patients with myeloma: a phase II study (PAV-trial).

    Science.gov (United States)

    Schmid, Andrea; Friess, Dorothea; Mansouri Taleghani, Behrouz; Keller, Peter; Mueller, Beatrice U; Baerlocher, Gabriela M; Leibundgut, Kurt; Pabst, Thomas

    2015-03-01

    Current practice in Switzerland for the mobilization of autologous stem cells in patients with myeloma is combining vinorelbine chemotherapy and granulocyte-colony stimulating factor (G-CSF) cytokine stimulation. We prospectively investigated adding intravenous plerixafor to the vinorelbine/G-CSF combination (VGP), and compared it with vinorelbine/plerixafor (VP) and G-CSF/plerixafor (GP) combinations. In a final cohort (VP-late), plerixafor was given on the first day of CD34 + cells increasing to > 15,000/mL peripheral blood. Four consecutive cohorts of 10 patients with myeloma were studied. We observed that intravenously administered plerixafor can be safely combined with vinorelbine/G-CSF. VGP was superior in mobilizing peripheral stem and progenitor cells compared to the three double combinations (VP, GP and VP-late), and GP mobilized better than VP. Our data indicate that the triple combination of VGP is an efficient strategy to collect autologous CD34 + cells, with G-CSF contributing predominantly in this concept. Plerixafor can be safely added to G-CSF and/or vinorelbine chemotherapy.

  6. Insulin resistance in vascular endothelial cells promotes intestinal tumour formation

    DEFF Research Database (Denmark)

    Wang, X; Häring, M-F; Rathjen, Thomas

    2017-01-01

    The risk of several cancers, including colorectal cancer, is increased in patients with obesity and type 2 diabetes, conditions characterised by hyperinsulinaemia and insulin resistance. Because hyperinsulinaemia itself is an independent risk factor for cancer development, we examined tissue...... did not change intestinal tumour number or size distribution on either a low or high-fat diet. We therefore asked whether cells in the tumour stroma might explain the association between tumour formation and insulin resistance. To this end, we generated Apc(Min/+) mice with loss of insulin receptors...... and increased the frequency of neutrophils in tumours. We conclude that although insulin is mitogenic for intestinal tumour cells in vitro, impaired insulin action in the tumour microenvironment may be more important in conditions where hyperinsulinaemia is secondary to insulin resistance. Insulin resistance...

  7. Colony Fusion in a Parthenogenetic Ant, Pristomyrmex punctatus

    Science.gov (United States)

    Satow, Show; Satoh, Toshiyuki; Hirota, Tadao

    2013-01-01

    In the ant Pristomyrmex punctatus Smith (Hymenoptera: Formicidae), all young workers lay a small number of eggs parthenogenetically. Some colonies consist of monoclonal individuals that provide high inclusive fitness, according to the kin selection theory. However, in some populations, a majority of the colonies contain multiple lineages. Intracolonial genetic variation of parthenogenetic ants cannot be explained by the multiple mating of single founderesses or by the foundation of a colony by multiple foundresses, which are the usual causes of genetically diverse colonies in social insects. Here, we hypothesized that the fusion of established colonies might facilitate the formation of multiclonal colonies. Colony fusion decreases indirect benefits because of the reduction in intracolonial relatedness. However, when suitable nesting places for overwintering are scarce, colony fusion provides a strategy for the survival of colonies. Here, ants derived from different colonies were allowed to encounter one another in a container with just one nesting place. Initially, high aggression was observed; however, after several days, no aggression was observed and the ants shared the nest. When the fused colonies were allowed to transfer to two alternative nests, ants from different colonies occupied the same nest. This study highlights the importance of limiting the number of nesting places in order to understand the genetic diversity of parthenogenetic ant colonies. PMID:23895053

  8. Transplanted Peripheral Blood Stem Cells Mobilized by Granulocyte Colony-Stimulating Factor Promoted Hindlimb Functional Recovery After Spinal Cord Injury in Mice.

    Science.gov (United States)

    Takahashi, Hiroshi; Koda, Masao; Hashimoto, Masayuki; Furuya, Takeo; Sakuma, Tsuyoshi; Kato, Kei; Okawa, Akihiko; Inada, Taigo; Kamiya, Koshiro; Ota, Mitsutoshi; Maki, Satoshi; Takahashi, Kazuhisa; Yamazaki, Masashi; Mannoji, Chikato

    2016-01-01

    Granulocyte colony-stimulating factor (G-CSF) mobilizes peripheral blood stem cells (PBSCs) derived from bone marrow. We hypothesized that intraspinal transplantation of PBSCs mobilized by G-CSF could promote functional recovery after spinal cord injury. Spinal cords of adult nonobese diabetes/severe immunodeficiency mice were injured using an Infinite Horizon impactor (60 kdyn). One week after the injury, 3.0 µl of G-CSF-mobilized human mononuclear cells (MNCs; 0.5 × 10(5)/µl), G-CSF-mobilized human CD34-positive PBSCs (CD34; 0.5 × 10(5)/µl), or normal saline was injected to the lesion epicenter. We performed immunohistochemistry. Locomotor recovery was assessed by Basso Mouse Scale. The number of transplanted human cells decreased according to the time course. The CD31-positive area was significantly larger in the MNC and CD34 groups compared with the vehicle group. The number of serotonin-positive fibers was significantly larger in the MNC and CD34 groups than in the vehicle group. Immunohistochemistry revealed that the number of apoptotic oligodendrocytes was significantly smaller in cell-transplanted groups, and the areas of demyelination in the MNC- and CD34-transplanted mice were smaller than that in the vehicle group, indicating that cell transplantation suppressed oligodendrocyte apoptosis and demyelination. Both the MNC and CD34 groups showed significantly better hindlimb functional recovery compared with the vehicle group. There was no significant difference between the two types of transplanted cells. Intraspinal transplantation of G-CSF-mobilized MNCs or CD34-positive cells promoted angiogenesis, serotonergic fiber regeneration/sparing, and preservation of myelin, resulting in improved hindlimb function after spinal cord injury in comparison with vehicle-treated control mice. Transplantation of G-CSF-mobilized PBSCs has advantages for treatment of spinal cord injury in the ethical and immunological viewpoints, although further exploration

  9. Granulocyte colony-stimulating factor decreases the Th1/Th2 ratio in peripheral blood mononuclear cells from patients with chronic immune thrombocytopenic purpura in vitro.

    Science.gov (United States)

    Ge, Fei; Zhang, Zhuo; Hou, Jinxiao; Cao, Fenglin; Zhang, Yingmei; Wang, Ping; Wei, Hong; Zhou, Jin

    2016-12-01

    Chronic immune thrombocytopenia purpura (ITP) is an autoimmune disease that exhibits an abnormally high Th1/Th2 ratio. Granulocyte colony-stimulating factor (G-CSF) has been shown to decrease the Th1/Th2 ratio in healthy donors. In this study, we investigated the effects of G-CSF treatment on the Th1/Th2 cells and the underlying mechanisms in patients with ITP in vitro. Peripheral blood mononuclear cells (PBMCs) isolated from patients with ITP and healthy controls were treated with G-CSF. Expression levels of interferon (IFN)-γ, interleukin (IL)-2, IL-4, and IL-13 in supernatants were measured by enzyme-linked immunosorbent assays. The expression of IFN-γ, IL-4, and G-CSF receptor (G-CSFR) on Th1 and Th2 cells were examined by flow cytometry and confocal microscopy. The mRNA expression of IFN-γ, IL-2, IL-4, IL-13, and T-box expressed in T cells (T-bet) and GATA-binding protein 3 (GATA-3) in PBMCs was evaluated by reverse transcription polymerase chain reaction. The results showed that G-CSF could significantly reduce the Th1/Th2 ratio in PBMCs from patients with ITP in vitro. As the concentration of G-CSF increased, Th1/Th2 ([IFN-γ+IL-2]/[IL-4+IL-13]) cytokine ratios and T-bet/GATA-3 mRNA ratios decreased in a concentration-dependent manner. Th1 cells and Th2 cells both expressed G-CSFR. These results suggest that G-CSF could decrease the Th1/Th2 ratio in the context of ITP, and elucidate the direct and indirect immunomodulatory mechanisms underlying G-CSF functions in Th1/Th2 cells, thus supporting the therapeutic potential of G-CSF in the treatment of patients with ITP. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. The role of granulocyte macrophage colony stimulating factor (GM-CSF) in radiation-induced tumor cell migration.

    Science.gov (United States)

    Vilalta, Marta; Brune, Jourdan; Rafat, Marjan; Soto, Luis; Graves, Edward E

    2018-03-13

    Recently it has been observed in preclinical models that that radiation enhances the recruitment of circulating tumor cells to primary tumors, and results in tumor regrowth after treatment. This process may have implications for clinical radiotherapy, which improves control of a number of tumor types but which, despite continued dose escalation and aggressive fractionation, is unable to fully prevent local recurrences. By irradiating a single tumor within an animal bearing multiple lesions, we observed an increase in tumor cell migration to irradiated and unirradiated sites, suggesting a systemic component to this process. Previous work has identified the cytokine GM-CSF, produced by tumor cells following irradiation, as a key effector of this process. We evaluated the ability of systemic injections of a PEGylated form of GM-CSF to stimulate tumor cell migration. While increases in invasion and migration were observed for tumor cells in a transwell assay, we found that daily injections of PEG-GM-CSF to tumor-bearing animals did not increase migration of cells to tumors, despite the anticipated changes in circulating levels of granulocytes and monocytes produced by this treatment. Combination of PEG-GM-CSF treatment with radiation also did not increase tumor cell migration. These findings suggest that clinical use of GM-CSF to treat neutropenia in cancer patients will not have negative effects on the aggressiveness of residual cancer cells. However, further work is needed to characterize the mechanism by which GM-CSF facilitates systemic recruitment of trafficking tumor cells to tumors.

  11. Protective layer formation on magnesium in cell culture medium

    Energy Technology Data Exchange (ETDEWEB)

    Wagener, V.; Virtanen, S., E-mail: virtanen@ww.uni-erlangen.de

    2016-06-01

    In the past, different studies showed that hydroxyapatite (HA) or similar calcium phosphates can be precipitated on Mg during immersion in simulated body fluids. However, at the same time, in most cases a dark grey or black layer is built under the white HA crystals. This layer seems to consist as well of calcium phosphates. Until now, neither the morphology nor its influence on Mg corrosion have been investigated in detail. In this work commercially pure magnesium (cp) was immersed in cell culture medium for one, three and five days at room temperature and in the incubator (37 °C, 5% CO{sub 2}). In addition, the influence of proteins on the formation of a corrosion layer was investigated by adding 20% of fetal calf serum (FCS) to the cell culture medium in the incubator. In order to analyze the formed layers, SEM images of cross sections, X-ray Photoelectron Spectroscopy (XPS), X-ray diffraction (XRD), Energy Dispersive X-ray Spectroscopy (EDX) and Fourier Transformed Infrared Spectroscopy (FTIR) measurements were carried out. Characterization of the corrosion behavior was achieved by electrochemical impedance spectroscopy (EIS) and by potentio-dynamic polarization in Dulbecco's Modified Eagle's Medium (DMEM) at 37 °C. Surface analysis showed that all formed layers consist mainly of amorphous calcium phosphate compounds. For the immersion at room temperature the Ca/P ratio indicates the formation of HA, while in the incubator probably pre-stages to HA are formed. The different immersion conditions lead to a variation in layer thicknesses. However, electrochemical characterization shows that the layer thickness does not influence the corrosion resistance of magnesium. The main influencing factor for the corrosion behavior is the layer morphology. Thus, immersion at room temperature leads to the highest corrosion protection due to the formation of a compact outer layer. Layers formed in the incubator show much worse performances due to completely porous

  12. Early modern state formation in the margins? A review of early modern popular politics and limited royal power in the Polish-Lithuanian Commonwealth and the Spanish colonial empire

    Directory of Open Access Journals (Sweden)

    Miia Ijäs

    2017-12-01

    Full Text Available The traditional historiography of early modern state-building has usually followed the western European paradigm of historiography, the usual models being France, England, Brandenburg-Prussia and Sweden. Regions that do not follow this paradigm have simply been left out and labeled “backward” or as “lagging behind”. In this literary review, our focus is on two different and rather surprising cases of early modern state formation: the Polish-Lithuanian Commonwealth and the Spanish colonial empire in Latin America. By following the scholarship on these two large conglomerates, we focus on two scholarly concepts: the idea of early modern realms as composite/conglomerate states, and state formation as a dynamic process involving several actors and interest groups. Our emphasis is particularly on sixteenth-century developments, as that century can be considered a thorough transition period in both regions. We hope that this literary review will bring the formerly marginalized conglomerates to the fore in discussion and research into state formation

  13. Fabric-based alkaline direct formate microfluidic fuel cells.

    Science.gov (United States)

    Domalaon, Kryls; Tang, Catherine; Mendez, Alex; Bernal, Franky; Purohit, Krutarth; Pham, Linda; Haan, John; Gomez, Frank A

    2017-04-01

    Fabric-based microfluidic fuel cells (MFCs) serve as a novel, cost-efficient alternative to traditional FCs and batteries, since fluids naturally travel across fabric via capillary action, eliminating the need for an external pump and lowering production and operation costs. Building on previous research with Y-shaped paper-based MFCs, fabric-based MFCs mitigate fragility and durability issues caused by long periods of fuel immersion. In this study, we describe a microfluidic fabric-based direct formate fuel cell, with 5 M potassium formate and 30% hydrogen peroxide as the anode fuel and cathode oxidant, respectively. Using a two-strip, stacked design, the optimized parameters include the type of encasement, the barrier, and the fabric type. Surface contact of the fabric and laminate sheet expedited flow and respective chemical reactions. The maximum current (22.83 mA/cm 2 ) and power (4.40 mW/cm 2 ) densities achieved with a 65% cotton/35% polyester blend material are a respective 8.7% and 32% higher than previous studies with Y-shaped paper-based MFCs. In series configuration, the MFCs generate sufficient energy to power a handheld calculator, a thermometer, and a spectrum of light-emitting diodes. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Segrosome complex formation during DNA trafficking in bacterial cell division

    Directory of Open Access Journals (Sweden)

    Maria A. Oliva

    2016-09-01

    Full Text Available Bacterial extrachromosomal DNAs often contribute to virulence in pathogenic organisms or facilitate adaptation to particular environments. The transmission of genetic information from one generation to the next requires sufficient partitioning of DNA molecules to ensure that at least one copy reaches each side of the division plane and is inherited by the daughter cells. Segregation of the bacterial chromosome occurs during or after replication and probably involves a strategy in which several protein complexes participate to modify the folding pattern and distribution first of the origin domain and then of the rest of the chromosome. Low-copy number plasmids rely on specialised partitioning systems, which in some cases use a mechanism that show striking similarity to eukaryotic DNA segregation. Overall, there have been multiple systems implicated in the dynamic transport of DNA cargo to a new cellular position during the cell cycle but most seem to share a common initial DNA partitioning step, involving the formation of a nucleoprotein complex called the segrosome. The particular features and complex topologies of individual segrosomes depend on both the nature of the DNA binding protein involved and on the recognized centromeric DNA sequence, both of which vary across systems. The combination of in vivo and in vitro approaches, with structural biology has significantly furthered our understanding of the mechanisms underlying DNA trafficking in bacteria. Here, I discuss recent advances and the molecular details of the DNA segregation machinery, focusing on the formation of the segrosome complex.

  15. Capillary network formation from dispersed endothelial cells: Influence of cell traction, cell adhesion, and extracellular matrix rigidity

    Science.gov (United States)

    Ramos, João R. D.; Travasso, Rui; Carvalho, João

    2018-01-01

    The formation of a functional vascular network depends on biological, chemical, and physical processes being extremely well coordinated. Among them, the mechanical properties of the extracellular matrix and cell adhesion are fundamental to achieve a functional network of endothelial cells, able to fully cover a required domain. By the use of a Cellular Potts Model and Finite Element Method it is shown that there exists a range of values of endothelial traction forces, cell-cell adhesion, and matrix rigidities where the network can spontaneously be formed, and its properties are characterized. We obtain the analytical relation that the minimum traction force required for cell network formation must obey. This minimum value for the traction force is approximately independent on the considered cell number and cell-cell adhesion. We quantify how these two parameters influence the morphology of the resulting networks (size and number of meshes).

  16. Germ Cell-less Promotes Centrosome Segregation to Induce Germ Cell Formation

    Directory of Open Access Journals (Sweden)

    Dorothy A. Lerit

    2017-01-01

    Full Text Available The primordial germ cells (PGCs specified during embryogenesis serve as progenitors to the adult germline stem cells. In Drosophila, the proper specification and formation of PGCs require both centrosomes and germ plasm, which contains the germline determinants. Centrosomes are microtubule (MT-organizing centers that ensure the faithful segregation of germ plasm into PGCs. To date, mechanisms that modulate centrosome behavior to engineer PGC development have remained elusive. Only one germ plasm component, Germ cell-less (Gcl, is known to play a role in PGC formation. Here, we show that Gcl engineers PGC formation by regulating centrosome dynamics. Loss of gcl leads to aberrant centrosome separation and elaboration of the astral MT network, resulting in inefficient germ plasm segregation and aborted PGC cellularization. Importantly, compromising centrosome separation alone is sufficient to mimic the gcl loss-of-function phenotypes. We conclude Gcl functions as a key regulator of centrosome separation required for proper PGC development.

  17. Adaptive T cell responses induced by oncolytic Herpes Simplex Virus-granulocyte macrophage-colony-stimulating factor therapy expanded by dendritic cell and cytokine-induced killer cell adoptive therapy.

    Science.gov (United States)

    Ren, Jun; Gwin, William R; Zhou, Xinna; Wang, Xiaoli; Huang, Hongyan; Jiang, Ni; Zhou, Lei; Agarwal, Pankaj; Hobeika, Amy; Crosby, Erika; Hartman, Zachary C; Morse, Michael A; H Eng, Kevin; Lyerly, H Kim

    2017-01-01

    Purpose : Although local oncolytic viral therapy (OVT) may enhance tumor lysis, antigen release, and adaptive immune responses, systemic antitumor responses post-therapy are limited. Adoptive immunotherapy with autologous dendritic cells (DC) and cytokine-induced killer cells (DC-CIK) synergizes with systemic therapies. We hypothesized that OVT with Herpes Simplex Virus-granulocyte macrophage-colony-stimulating factor (HSV-GM-CSF) would induce adaptive T cell responses that could be expanded systemically with sequential DC-CIK therapy. Patients and Methods : We performed a pilot study of intratumoral HSV-GM-CSF OVT followed by autologous DC-CIK cell therapy. In addition to safety and clinical endpoints, we monitored adaptive T cell responses by quantifying T cell receptor (TCR) populations in pre-oncolytic therapy, post-oncolytic therapy, and after DC-CIK therapy. Results : Nine patients with advanced malignancy were treated with OVT (OrienX010), of whom seven experienced stable disease (SD). Five of the OVT treated patients underwent leukapheresis, generation, and delivery of DC-CIKs, and two had SD, whereas three progressed. T cell receptor sequencing of TCR β sequences one month after OVT therapy demonstrates a dynamic TCR repertoire in response to OVT therapy in the majority of patients with the systematic expansion of multiple T cell clone populations following DC-CIK therapy. This treatment was well tolerated and long-term event free and overall survival was observed in six of the nine patients. Conclusions : Strategies inducing the local activation of tumor-specific immune responses can be combined with adoptive cellular therapies to expand the adaptive T cell responses systemically and further studies are warranted.

  18. S6Ks isoforms contribute to viability, migration, docetaxel resistance and tumor formation of prostate cancer cells

    International Nuclear Information System (INIS)

    Amaral, Camila L.; Freitas, Lidia B.; Tamura, Rodrigo E.; Tavares, Mariana R.; Pavan, Isadora C. B.; Bajgelman, Marcio C.; Simabuco, Fernando M.

    2016-01-01

    The S6 Kinase (S6K) proteins are some of the main downstream effectors of the mammalian Target Of Rapamycin (mTOR) and act as key regulators of protein synthesis and cell growth. S6K is overexpressed in a variety of human tumors and is correlated to poor prognosis in prostate cancer. Due to the current urgency to identify factors involved in prostate cancer progression, we aimed to reveal the cellular functions of three S6K isoforms–p70-S6K1, p85-S6K1 and p54-S6K2–in prostate cancer, as well as their potential as therapeutic targets. In this study we performed S6K knockdown and overexpression and investigated its role in prostate cancer cell proliferation, colony formation, viability, migration and resistance to docetaxel treatment. In addition, we measured tumor growth in Nude mice injected with PC3 cells overexpressing S6K isoforms and tested the efficacy of a new available S6K1 inhibitor in vitro. S6Ks overexpression enhanced PC3-luc cell line viability, migration, resistance to docetaxel and tumor formation in Nude mice. Only S6K2 knockdown rendered prostate cancer cells more sensitive to docetaxel. S6K1 inhibitor PF-4708671 was particularly effective for reducing migration and proliferation of PC3 cell line. These findings demonstrate that S6Ks play an important role in prostate cancer progression, enhancing cell viability, migration and chemotherapy resistance, and place both S6K1 and S6K2 as a potential targets in advanced prostate cancer. We also provide evidence that S6K1 inhibitor PF-4708671 may be considered as a potential drug for prostate cancer treatment. The online version of this article (doi:10.1186/s12885-016-2629-y) contains supplementary material, which is available to authorized users

  19. Number of colony-forming unit-Hill colonies among children and teenagers with obesity, dyslipidemia and breastfeeding history.

    Science.gov (United States)

    Salazar-Martinez, E; Rodriguez-Valentin, R; Albavera-Hernandez, C; Carreon-Rodriguez, A; Lazcano-Ponce, E

    2016-06-01

    The number of colony-forming unit (CFU)-Hill colonies has been proposed as a biomarker of vascular function and cardiovascular risk in adults but information about its role in children is scarce. This study evaluates the associations between obesity, cardiovascular risk factors and breastfeeding history with the numbers of CFU-Hill colonies in a sample of young people. We selected 49 children and teenagers between ages 10 and 17 (65.3% boys) from Mexican Health Care system. Physical activity and Anthropometric measures data were registered. CFU-Hill colonies were cultured from mononuclear cells obtained from venous blood. We detected inverse associations between the formation of CFU-Hill colonies and body mass index (BMI; β = -1.53; 95% confidence interval [CI], -1.92, -1.13), triglycerides (β = -0.26; 95%CI = -0.34, -0.18), total cholesterol (β = -0.13; 95%CI = -0.17, -0.08), Low Density Lipoprotein (LDL) (β = -0.20; 95%CI = -0.31, -0.09) and glucose (β = -0.37; 95%CI = -0.55, -0.18) using multivariate models. Breastfeeding duration showed a 1.46-colony increase for each month of breastfeeding (95%CI = 0.73, 2.18). CFU-Hill colony-forming capacity in children and teenagers was inversely associated with obesity, dyslipidemia and high blood levels of glucose. In contrast a longer breastfeeding duration was directly associated with an increased number of CFU-Hill colonies. However these results must be confirmed with further studies. Our findings support the importance of promoting breastfeeding and monitoring nutritional and metabolic status at an early age to prevent chronic disease development. Copyright © 2016 The Italian Society of Diabetology, the Italian Society for the Study of Atherosclerosis, the Italian Society of Human Nutrition, and the Department of Clinical Medicine and Surgery, Federico II University. Published by Elsevier B.V. All rights reserved.

  20. Dexamethasone prevents granulocyte-macrophage colony-stimulating factor-induced nuclear factor-κB activation, inducible nitric oxide synthase expression and nitric oxide production in a skin dendritic cell line

    Directory of Open Access Journals (Sweden)

    Ana Luísa Vital

    2003-01-01

    Full Text Available Aims: Nitric oxide (NO has been increasingly implicated in inflammatory skin diseases, namely in allergic contact dermatitis. In this work, we investigated the effect of dexamethasone on NO production induced by the epidermal cytokine granulocyte-macrophage colony-stimulating factor (GM-CSF in a mouse fetal skin dendritic cell line.

  1. Combined immunotherapy with granulocyte-macrophage colony-stimulating factor-transduced allogeneic prostate cancer cells and ipilimumab in patients with metastatic castration-resistant prostate cancer: a phase 1 dose-escalation trial

    NARCIS (Netherlands)

    Eertwegh, A.J. van den; Versluis, J.; van den Berg, H.P.; Santegoets, S.J.; van Moorselaar, R.J.; van der Sluis, T.M.; Gall, H.E.; Harding, T.C.; Jooss, K.; Lowy, I.; Pinedo, H.M.; Scheper, R.J.; Stam, A.G.; Blomberg, B.M. von; Gruijl, T.D. de; Hege, K.; Sacks, N.; Gerritsen, W.R.

    2012-01-01

    BACKGROUND: The granulocyte-macrophage colony-stimulating factor-transduced allogeneic prostate cancer cells vaccine (GVAX) has antitumour activity against prostate cancer; preclinical studies have shown potent synergy when combined with ipilimumab, an antibody that blocks cytotoxic T-lymphocyte

  2. Instent neointimal hyperplasia after percutaneous intervention for ST-elevation myocardial infarction and treatment with granulocyte-colony stimulating factor. Results from the stem cells in myocardial infarction (STEMMI) trial

    DEFF Research Database (Denmark)

    Jørgensen, Erik; Baldazzi, Federica; Ripa, Rasmus S

    2010-01-01

    Recombinant granulocyte-colony stimulating factor (G-CSF) mobilized pluripotent cells from the bone marrow are proposed to have a regenerative potential. Though, a report of excessive instent restenosis, in patients treated with G-CSF before percutaneous coronary intervention (PCI) warrants caution....

  3. Cell renewal and ground substance formation in replanted cat teeth

    Energy Technology Data Exchange (ETDEWEB)

    Kvinnsland, I.; Heyeraas, K.J. (Bergen Univ. (Norway))

    1990-01-01

    The cellular dynamic pattern of pulpal healing 4, 10, 30 and 60 days after replantation of 47 apioectomized cat incisors was studied after pulse labelling with {sup 3}H-thymidine and {sup 35}S- sulfate, autoradiography, and routine histology. In the control teeth the labelling index was less than 0.05%. The apical pulpal cells were capable of ground substance formation and cell proliferation already four days after replantation, with a labelling index of 7%, which increased up to 43% within 10 days. A gradual postoperative restitution and reorganization within the pulpal cellular compartment was seen. The maximum cell density, reached after 30 days, was reduced to on average 60% compared with the controls. The tissue reorganization was near completion within all pulpal zones after 60 days, and the labelling index was reduced to 2.5%. In some instances internal resorption in cervical pulpal areas negatively influenced the favorable healing. The present study shows that the pulpal healing in replanted teeth follows a consistent basic pattern in cellular dynamics and in histologic changes. The replanted tooth thus seems to be a suitable model for studies of healing and repair in connective tissues. 27 refs., 4 figs., 2 tabs.

  4. Effects of Granulocyte-Macrophage Colony-Stimulating (GM-CSF) Factor on Corneal Epithelial Cells in Corneal Wound Healing Model.

    Science.gov (United States)

    Rho, Chang Rae; Park, Mi-young; Kang, Seungbum

    2015-01-01

    Granulocyte-macrophage colony-stimulating factor (GM-CSF) is a pleiotropic cytokine that activates granulocyte and macrophage cell lineages. It is also known to have an important function in wound healing. This study investigated the effect of GM-CSF in wound healing of human corneal epithelial cells (HCECs). We used human GM-CSF derived from rice cells (rice cell-derived recombinant human GM-CSF; rhGM-CSF). An in vitro migration assay was performed to investigate the migration rate of HCECs treated with various concentrations of rhGM-CSF (0.1, 1.0, and 10.0 μg/ml). MTT assay and flow cytometric analysis were used to evaluate the proliferative effect of rhGM-CSF. The protein level of p38MAPK was analyzed by western blotting. For in vivo analysis, 100 golden Syrian hamsters were divided into four groups, and their corneas were de-epithelialized with alcohol and a blade. The experimental groups were treated with 10, 20, or 50 μg/ml rhGM-CSF four times daily, and the control group was treated with phosphate-buffered saline. The corneal wound-healing rate was evaluated by fluorescein staining at the initial wounding and 12, 24, 36, and 48 hours after epithelial debridement. rhGM-CSF accelerated corneal epithelial wound healing both in vitro and in vivo. MTT assay and flow cytometric analysis revealed that rhGM-CSF treatment had no effects on HCEC proliferation. Western blot analysis demonstrated that the expression level of phosphorylated p38MAPK increased with rhGM-CSF treatment. These findings indicate that rhGM-CSF enhances corneal wound healing by accelerating cell migration.

  5. Effects of Granulocyte-Macrophage Colony-Stimulating (GM-CSF Factor on Corneal Epithelial Cells in Corneal Wound Healing Model.

    Directory of Open Access Journals (Sweden)

    Chang Rae Rho

    Full Text Available Granulocyte-macrophage colony-stimulating factor (GM-CSF is a pleiotropic cytokine that activates granulocyte and macrophage cell lineages. It is also known to have an important function in wound healing. This study investigated the effect of GM-CSF in wound healing of human corneal epithelial cells (HCECs. We used human GM-CSF derived from rice cells (rice cell-derived recombinant human GM-CSF; rhGM-CSF. An in vitro migration assay was performed to investigate the migration rate of HCECs treated with various concentrations of rhGM-CSF (0.1, 1.0, and 10.0 μg/ml. MTT assay and flow cytometric analysis were used to evaluate the proliferative effect of rhGM-CSF. The protein level of p38MAPK was analyzed by western blotting. For in vivo analysis, 100 golden Syrian hamsters were divided into four groups, and their corneas were de-epithelialized with alcohol and a blade. The experimental groups were treated with 10, 20, or 50 μg/ml rhGM-CSF four times daily, and the control group was treated with phosphate-buffered saline. The corneal wound-healing rate was evaluated by fluorescein staining at the initial wounding and 12, 24, 36, and 48 hours after epithelial debridement. rhGM-CSF accelerated corneal epithelial wound healing both in vitro and in vivo. MTT assay and flow cytometric analysis revealed that rhGM-CSF treatment had no effects on HCEC proliferation. Western blot analysis demonstrated that the expression level of phosphorylated p38MAPK increased with rhGM-CSF treatment. These findings indicate that rhGM-CSF enhances corneal wound healing by accelerating cell migration.

  6. TRPC3-mediated Ca2+ signals as a promising strategy to boost therapeutic angiogenesis in failing hearts: The role of autologous endothelial colony forming cells.

    Science.gov (United States)

    Moccia, Francesco; Lucariello, Angela; Guerra, Germano

    2018-05-01

    Endothelial progenitor cells (EPCs) are a sub-population of bone marrow-derived mononuclear cells that are released in circulation to restore damaged endothelium during its physiological turnover or rescue blood perfusion after an ischemic insult. Additionally, they may be mobilized from perivascular niches located within larger arteries' wall in response to hypoxic conditions. For this reason, EPCs have been regarded as an effective tool to promote revascularization and functional recovery of ischemic hearts, but clinical application failed to exploit the full potential of patients-derived cells. Indeed, the frequency and biological activity of EPCs are compromised in aging individuals or in subjects suffering from severe cardiovascular risk factors. Rejuvenating the reparative phenotype of autologous EPCs through a gene transfer approach has, therefore, been put forward as an alternative approach to enhance their therapeutic potential in cardiovascular patients. An increase in intracellular Ca 2+ concentration constitutes a pivotal signal for the activation of the so-called endothelial colony forming cells (ECFCs), the only known truly endothelial EPC subset. Studies from our group showed that the Ca 2+ toolkit differs between peripheral blood- and umbilical cord blood (UCB)-derived ECFCs. In the present article, we first discuss how VEGF uses repetitive Ca 2+ spikes to regulate angiogenesis in ECFCs and outline how VEGF-induced intracellular Ca 2+ oscillations differ between the two ECFC subtypes. We then hypothesize about the possibility to rejuvenate the biological activity of autologous ECFCs by transfecting the cell with the Ca 2+ -permeable channel Transient Receptor Potential Canonical 3, which selectively drives the Ca 2+ response to VEGF in UCB-derived ECFCs. © 2017 Wiley Periodicals, Inc.

  7. Detection and quantification of intracellular bacterial colonies by automated, high-throughput microscopy.

    Science.gov (United States)

    Ernstsen, Christina L; Login, Frédéric H; Jensen, Helene H; Nørregaard, Rikke; Møller-Jensen, Jakob; Nejsum, Lene N

    2017-08-01

    To target bacterial pathogens that invade and proliferate inside host cells, it is necessary to design intervention strategies directed against bacterial attachment, cellular invasion and intracellular proliferation. We present an automated microscopy-based, fast, high-throughput method for analyzing size and number of intracellular bacterial colonies in infected tissue culture cells. Cells are seeded in 48-well plates and infected with a GFP-expressing bacterial pathogen. Following gentamicin treatment to remove extracellular pathogens, cells are fixed and cell nuclei stained. This is followed by automated microscopy and subsequent semi-automated spot detection to determine the number of intracellular bacterial colonies, their size distribution, and the average number per host cell. Multiple 48-well plates can be processed sequentially and the procedure can be completed in one working day. As a model we quantified intracellular bacterial colonies formed by uropathogenic Escherichia coli (UPEC) during infection of human kidney cells (HKC-8). Urinary tract infections caused by UPEC are among the most common bacterial infectious diseases in humans. UPEC can colonize tissues of the urinary tract and is responsible for acute, chronic, and recurrent infections. In the bladder, UPEC can form intracellular quiescent reservoirs, thought to be responsible for recurrent infections. In the kidney, UPEC can colonize renal epithelial cells and pass to the blood stream, either via epithelial cell disruption or transcellular passage, to cause sepsis. Intracellular colonies are known to be clonal, originating from single invading UPEC. In our experimental setup, we found UPEC CFT073 intracellular bacterial colonies to be heterogeneous in size and present in nearly one third of the HKC-8 cells. This high-throughput experimental format substantially reduces experimental time and enables fast screening of the intracellular bacterial load and cellular distribution of multiple

  8. Formation of Cell-To-Cell Connection between Bone Marrow Cells and Isolated Rat Cardiomyocytes in a Cocultivation Model

    Czech Academy of Sciences Publication Activity Database

    Skopalík, J.; Pásek, Michal; Rychtárik, M.; Koristek, Z.; Gabrielová, E.; Sheer, P.; Matejovič, P.; Modrianský, M.; Klabusay, M.

    2014-01-01

    Roč. 5, č. 5 (2014), s. 1000185 ISSN 2157-7013 Institutional support: RVO:61388998 Keywords : bone marrow * mononuclear cells * isolated cardiomyocytes * cocultivation Subject RIV: BO - Biophysics http://omicsonline.org/ open - access /formation-of-celltocell-connection-between-bone-marrow-cells- and -isolated-rat-cardiomyocytes-2157-7013.1000185.php?aid=33364

  9. Effect ot thymus cells on the radiosensitivity and differentiation trends of hematopoietic stem cells

    Energy Technology Data Exchange (ETDEWEB)

    Shvets, V.N.

    1976-10-01

    A stimulating influence of thymus cells on the capability of irradiated (from 100 to 500 R) bone marrow of mice of producing colonies in spleen of syngenous recipient has been proven. The intensification of colony formation involves an increased radioresistance of stem cells. It is supposed that radioresistant thymus cells have a stimulating effect. Thymus cells exert their influence not only to the rate of survival of stem cells proliferating in the bone marrow of femur, but also increase their erythropoetic potention.

  10. Hematologic recovery in patients who are treated with autologous stem cells transplantation taken from bone marrow after granulocyte-colony-stimulating factor stimulation.

    Science.gov (United States)

    Gawronski, K; Rzepecki, P; Oborska, S; Wasko-Grabowska, A

    2011-10-01

    We sought to compare hematologic recovery between patients who did or did not receive granulocyte-colony-stimulating factor (G-CSF)-stimulated bone marrow (rich bone marrow [RBM]). The study subjects were 20 patients whose bone marrow was taken without prior stimulation with G-CSF and 15 patients in whom bone marrow was taken after previous G-CSF mobilization. The bone marrow harvest took place on the fifth day after G-CSF initiation. The bone marrow aliquot was 20 mL/kg. The median value of nucleated cells obtained from patients without G-CSF preparation was 3.65×10(8)/kg. The median value of nucleated cells from RBM patients was 4.83×10(8)/kg. The median value of stem cells obtained from patients without G-CSF preparation was 0.96×10(6)/kg versus 1.9×10(6)/kg from RBM patients. The median time to recovery of the hematopoietic system based on an increase in PLT value>20 g/L was 12.6 days for RBM versus 18.8 days without G-CSF preparation. The median time to recovery of the hematopoietic system based on assessment of growth ANC>0.5 g/L was 13.0 days for RBM versus 17.8 days without G-CSF stimulation. Significantly higher values of nucleated cells and increased stem cells were observed among RBM patients compared with those whose bone marrow was harvested without any stimulation (P=.01). There was faster recovery of the hematopoietic system in cases where bone marrow was collected after G-CSF: PLT>20 g/L (P=.015) and ANC>0.5 g/L (P=.01). We also observed that the use of stimulated bone marrow shortened hospital stay after the administration of hematopoietic cells to 17.3 days compared with 23.1 days among patients receiving hematopoietic cells from nonstimulated bone marrow. The number of complications during transplantation was comparable in both cases, the most frequent ones being febrile neutropenia and grade III and IV mucositis. RBM is a better method to obtain stem cells from bone marrow. Stimulated bone marrow shows faster engraftment compared with

  11. Direct effects of caffeine on osteoblastic cells metabolism: the possible causal effect of caffeine on the formation of osteoporosis

    Directory of Open Access Journals (Sweden)

    Chen Li-Ting

    2006-10-01

    Full Text Available Abstract Background Caffeine consumption has been reported to decrease bone mineral density (BMD, increase the risk of hip fracture, and negatively influence calcium retention. In this study, we investigated the influence of caffeine on the osteoblasts behaviour. Method Osteoblasts derived from newborn Wistar-rat calvaria was used in this study. The effects of various concentrations of caffeine on bone cell activities were evaluated by using MTT assay. Alkaline phosphatase (ALP staining, von Kossa staining and biochemical parameters including ALP, lactate dehydrogenase (LDH, prostaglandin E2 (PGE2 and total protein were performed at day 1, 3, and 7. DNA degradation analysis under the caffeine influence was also performed. Results and discussion The results showed that the viability of the osteoblasts, the formation of ALP positive staining colonies and mineralization nodules formation in the osteoblasts cultures decreased significantly in the presence of 10 mM caffeine. The intracellular LDH, ALP and PGE2 content decreased significantly, the LDH and PGE2 secreted into the medium increased significantly. The activation of an irreversible commitment to cell death by caffeine was clearly demonstrated by DNA ladder staining. Conclusion In summary, our results suggest that caffeine has potential deleterious effect on the osteoblasts viability, which may enhance the rate of osteoblasts apoptosis.

  12. Buckling instability in ordered bacterial colonies

    Science.gov (United States)

    Boyer, Denis; Mather, William; Mondragón-Palomino, Octavio; Orozco-Fuentes, Sirio; Danino, Tal; Hasty, Jeff; Tsimring, Lev S.

    2011-04-01

    Bacterial colonies often exhibit complex spatio-temporal organization. This collective behavior is affected by a multitude of factors ranging from the properties of individual cells (shape, motility, membrane structure) to chemotaxis and other means of cell-cell communication. One of the important but often overlooked mechanisms of spatio-temporal organization is direct mechanical contact among cells in dense colonies such as biofilms. While in natural habitats all these different mechanisms and factors act in concert, one can use laboratory cell cultures to study certain mechanisms in isolation. Recent work demonstrated that growth and ensuing expansion flow of rod-like bacteria Escherichia coli in confined environments leads to orientation of cells along the flow direction and thus to ordering of cells. However, the cell orientational ordering remained imperfect. In this paper we study one mechanism responsible for the persistence of disorder in growing cell populations. We demonstrate experimentally that a growing colony of nematically ordered cells is prone to the buckling instability. Our theoretical analysis and discrete-element simulations suggest that the nature of this instability is related to the anisotropy of the stress tensor in the ordered cell colony.

  13. Combination therapy of human umbilical cord blood cells and granulocyte colony stimulating factor reduces histopathological and motor impairments in an experimental model of chronic traumatic brain injury.

    Directory of Open Access Journals (Sweden)

    Sandra A Acosta

    Full Text Available Traumatic brain injury (TBI is associated with neuro-inflammation, debilitating sensory-motor deficits, and learning and memory impairments. Cell-based therapies are currently being investigated in treating neurotrauma due to their ability to secrete neurotrophic factors and anti-inflammatory cytokines that can regulate the hostile milieu associated with chronic neuroinflammation found in TBI. In tandem, the stimulation and mobilization of endogenous stem/progenitor cells from the bone marrow through granulocyte colony stimulating factor (G-CSF poses as an attractive therapeutic intervention for chronic TBI. Here, we tested the potential of a combined therapy of human umbilical cord blood cells (hUCB and G-CSF at the acute stage of TBI to counteract the progressive secondary effects of chronic TBI using the controlled cortical impact model. Four different groups of adult Sprague Dawley rats were treated with saline alone, G-CSF+saline, hUCB+saline or hUCB+G-CSF, 7-days post CCI moderate TBI. Eight weeks after TBI, brains were harvested to analyze hippocampal cell loss, neuroinflammatory response, and neurogenesis by using immunohistochemical techniques. Results revealed that the rats exposed to TBI treated with saline exhibited widespread neuroinflammation, impaired endogenous neurogenesis in DG and SVZ, and severe hippocampal cell loss. hUCB monotherapy suppressed neuroinflammation, nearly normalized the neurogenesis, and reduced hippocampal cell loss compared to saline alone. G-CSF monotherapy produced partial and short-lived benefits characterized by low levels of neuroinflammation in striatum, DG, SVZ, and corpus callosum and fornix, a modest neurogenesis, and a moderate reduction of hippocampal cells loss. On the other hand, combined therapy of hUCB+G-CSF displayed synergistic effects that robustly dampened neuroinflammation, while enhancing endogenous neurogenesis and reducing hippocampal cell loss. Vigorous and long-lasting recovery of

  14. Botryllus schlosseri (Tunicata) whole colony irradiation: Do senescent zooid resorption and immunological resorption involve similar recognition events

    Energy Technology Data Exchange (ETDEWEB)

    Rinkevich, B.; Weissman, I.L. (Israel Oceanographic and Limnological Research, Haifa (Israel))

    1990-02-01

    The colonial tunicate Botryllus schlosseri undergoes cyclic blastogenesis where feeding zooids are senescened and resorbed and a new generation of zooids takes over the colony. When non-identical colonies come into direct contact, they either reject each other or fuse. Fusion is usually followed by the resorption of one of the partners in the chimera (immunological resorption). The striking morphological similarities between the two resorption phenomena suggest that both may involve tissue destruction following self-nonself recognition events. Here we attempt to modify these two events by whole colony gamma irradiation assays. Three sets of experiments were performed: (1) different doses of whole colony irradiation for determination of irradiation effects (110 colonies); (2) pairs of irradiated-nonirradiated isografts of clonal replicates for the potential of reconstruction of the irradiated partners (23 pairs); (3) chimeras of irradiated-nonirradiated partners for analysis of resorption hierarchy. Mortality increased with the irradiation dose. All colonies exposed to more than 5,000 rads died within 19 days, while no colony died below 2,000 rads. The average mortality periods, in days, for doses of 6,000-8,000, 5,000, and 2,500-4,000 rads were 14.4 +/- 3.1 (n = 24), 19.8 +/- 6.0 (n = 15), and 19.6 + 5.1 (n = 22), respectively. Younger colonies (3-6 months old) may survive radiation better than older ones (more than 13 months). Many morphological alterations were recorded in irradiated colonies: ampullar contraction and/or dilation, accumulation of pigment cells within ampullae, abnormal bleeding from blood vessels, sluggish blood circulation, necrotic zones, reduction in bud number, and irregularities in zooid and system structures. With doses of 3,000-4,000 rads and above, irradiation arrested the formation of new buds and interrupted normal takeover.

  15. Differentiation-independent fluctuation of pluripotency-related transcription factors and other epigenetic markers in embryonic stem cell colonies

    Czech Academy of Sciences Publication Activity Database

    Šustáčková, Gabriela; Legartová, Soňa; Kozubek, Stanislav; Stixová, Lenka; Pacherník, J.; Bártová, Eva

    2012-01-01

    Roč. 21, č. 5 (2012), s. 710-720 ISSN 1547-3287 R&D Projects: GA MŠk(CZ) LC535; GA MŠk(CZ) LC06027; GA MŠk(CZ) ME 919; GA ČR(CZ) GAP302/10/1022 Institutional research plan: CEZ:AV0Z50040507 Keywords : ES cells * epigenetics * Oct4 Subject RIV: BO - Biophysics Impact factor: 4.670, year: 2012

  16. Diclofenac in Arabidopsis cells: Rapid formation of conjugates.

    Science.gov (United States)

    Fu, Qiuguo; Ye, Qingfu; Zhang, Jianbo; Richards, Jaben; Borchardt, Dan; Gan, Jay

    2017-03-01

    Pharmaceutical and personal care products (PPCPs) are continuously introduced into the soil-plant system, through practices such as agronomic use of reclaimed water and biosolids containing these trace contaminants. Plants may accumulate PPCPs from soil, serving as a conduit for human exposure. Metabolism likely controls the final accumulation of PPCPs in plants, but is in general poorly understood for emerging contaminants. In this study, we used diclofenac as a model compound, and employed 14 C tracing, and time-of-flight (TOF) and triple quadruple (QqQ) mass spectrometers to unravel its metabolism pathways in Arabidopsis thaliana cells. We further validated the primary metabolites in Arabidopsis seedlings. Diclofenac was quickly taken up into A. thaliana cells. Phase I metabolism involved hydroxylation and successive oxidation and cyclization reactions. However, Phase I metabolites did not accumulate appreciably; they were instead rapidly conjugated with sulfate, glucose, and glutamic acid through Phase II metabolism. In particular, diclofenac parent was directly conjugated with glutamic acid, with acyl-glutamatyl-diclofenac accounting for >70% of the extractable metabolites after 120-h incubation. In addition, at the end of incubation, >40% of the spiked diclofenac was in the non-extractable form, suggesting extensive sequestration into cell matter. The rapid formation of non-extractable residue and dominance of diclofenac-glutamate conjugate uncover previously unknown metabolism pathways for diclofenac. In particular, the rapid conjugation of parent highlights the need to consider conjugates of emerging contaminants in higher plants, and their biological activity and human health implications. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Buckling instability in ordered bacterial colonies

    International Nuclear Information System (INIS)

    Boyer, Denis; Mather, William; Mondragón-Palomino, Octavio; Danino, Tal; Hasty, Jeff; Orozco-Fuentes, Sirio; Tsimring, Lev S

    2011-01-01

    Bacterial colonies often exhibit complex spatio-temporal organization. This collective behavior is affected by a multitude of factors ranging from the properties of individual cells (shape, motility, membrane structure) to chemotaxis and other means of cell–cell communication. One of the important but often overlooked mechanisms of spatio-temporal organization is direct mechanical contact among cells in dense colonies such as biofilms. While in natural habitats all these different mechanisms and factors act in concert, one can use laboratory cell cultures to study certain mechanisms in isolation. Recent work demonstrated that growth and ensuing expansion flow of rod-like bacteria Escherichia coli in confined environments leads to orientation of cells along the flow direction and thus to ordering of cells. However, the cell orientational ordering remained imperfect. In this paper we study one mechanism responsible for the persistence of disorder in growing cell populations. We demonstrate experimentally that a growing colony of nematically ordered cells is prone to the buckling instability. Our theoretical analysis and discrete-element simulations suggest that the nature of this instability is related to the anisotropy of the stress tensor in the ordered cell colony

  18. Colony Stimulating Factor-1 Receptor Expressing Cells Infiltrating the Cornea Control Corneal Nerve Degeneration in Response to HSV-1 Infection.

    Science.gov (United States)

    Chucair-Elliott, Ana J; Gurung, Hem R; Carr, Meghan M; Carr, Daniel J J

    2017-09-01

    Herpes simplex virus type-1 (HSV-1) is a leading cause of neurotrophic keratitis, characterized by decreased or absent corneal sensation due to damage to the sensory corneal innervation. We previously reported the elicited immune response to infection contributes to the mechanism of corneal nerve regression/damage during acute HSV-1 infection. Our aim is to further establish the involvement of infiltrated macrophages in the mechanism of nerve loss upon infection. Macrophage Fas-Induced Apoptosis (MAFIA) transgenic C57BL/6 mice were systemically treated with AP20187 dimerizer or vehicle (VEH), and their corneas, lymph nodes, and blood were assessed for CD45+CD11b+GFP+ cell depletion by flow cytometry (FC). Mice were ocularly infected with HSV-1 or left uninfected. At 2, 4, and/or 6 days post infection (PI), corneas were assessed for sensitivity and harvested for FC, nerve structure by immunohistochemistry, viral content by plaque assay, soluble factor content by suspension array, and activation of signaling pathways by Western blot analysis. C57BL6 mice were used to compare to the MAFIA mouse model. MAFIA mice treated with AP20187 had efficient depletion of CD45+CD11b+GFP+ cells in the tissues analyzed. The reduction of CD45+CD11b+GFP+ cells recruited to the infected corneas of AP20187-treated mice correlated with preservation of corneal nerve structure and function, decreased protein concentration of inflammatory cytokines, and decreased STAT3 activation despite no changes in viral content in the cornea compared to VEH-treated animals. Our results suggest infiltrated macrophages are early effectors in the nerve regression following HSV-1 infection. We propose the neurodegeneration mechanism involves macrophages, local up-regulation of IL-6, and activation of STAT3.

  19. Specters of Colonialism

    DEFF Research Database (Denmark)

    Muhr, Sara Louise; Azad, Salam

    2013-01-01

    This paper investigates how an organization in Sweden, a country normally not considered among the former colonial powers, is still haunted by the specters of a western colonial history. Based on in-depth interviews as well as participant observation in the headquarters of a Swedish multinational...... organization, we show how an overarching colonial discourse – although not acknowledged – shapes the experience that foreign employees have of work. This leaves foreign workers in an integration dilemma, as they are expected to suppress home-country values and identities in order to become accepted, while...... at the same time they always are bound to fail to become ‘Swedish’ because of the same foreign origins. Although Swedish culture – partly by distancing itself from having a colonial past – has successfully built up an image of openness, we argue that without acknowledging and confronting the role...

  20. Mind bomb 1 is required for pancreatic ß-cell formation

    DEFF Research Database (Denmark)

    Horn, Signe; Kobberup, Sune; Jørgensen, Mette C

    2012-01-01

    the insulin producing ß-cells. However, signals that regulate proximodistal (P-D) patterning and thus formation of ß-cell progenitors are unknown. Here we show that Mind bomb 1 (Mib1) is required for correct P-D patterning of the developing pancreas and ß-cell formation. We found that endoderm...

  1. High frequency of endothelial colony forming cells marks a non-active myeloproliferative neoplasm with high risk of splanchnic vein thrombosis.

    Directory of Open Access Journals (Sweden)

    Vittorio Rosti

    Full Text Available Increased mobilization of circulating endothelial progenitor cells may represent a new biological hallmark of myeloproliferative neoplasms. We measured circulating endothelial colony forming cells (ECFCs in 106 patients with primary myelofibrosis, fibrotic stage, 49 with prefibrotic myelofibrosis, 59 with essential thrombocythemia or polycythemia vera, and 43 normal controls. Levels of ECFC frequency for patient's characteristics were estimated by using logistic regression in univariate and multivariate setting. The sensitivity, specificity, likelihood ratios, and positive predictive value of increased ECFC frequency were calculated for the significantly associated characteristics. Increased frequency of ECFCs resulted independently associated with history of splanchnic vein thrombosis (adjusted odds ratio = 6.61, 95% CI = 2.54-17.16, and a summary measure of non-active disease, i.e. hemoglobin of 13.8 g/dL or lower, white blood cells count of 7.8×10(9/L or lower, and platelet count of 400×10(9/L or lower (adjusted odds ratio = 4.43, 95% CI = 1.45-13.49 Thirteen patients with splanchnic vein thrombosis non associated with myeloproliferative neoplasms were recruited as controls. We excluded a causal role of splanchnic vein thrombosis in ECFCs increase, since no control had elevated ECFCs. We concluded that increased frequency of ECFCs represents the biological hallmark of a non-active myeloproliferative neoplasm with high risk of splanchnic vein thrombosis. The recognition of this disease category copes with the phenotypic mimicry of myeloproliferative neoplasms. Due to inherent performance limitations of ECFCs assay, there is an urgent need to arrive to an acceptable standardization of ECFC assessment.

  2. Deformed wing virus implicated in overwintering honeybee colony losses.

    Science.gov (United States)

    Highfield, Andrea C; El Nagar, Aliya; Mackinder, Luke C M; Noël, Laure M-L J; Hall, Matthew J; Martin, Stephen J; Schroeder, Declan C

    2009-11-01

    The worldwide decline in honeybee colonies during the past 50 years has often been linked to the spread of the parasitic mite Varroa destructor and its interaction with certain honeybee viruses. Recently in the United States, dramatic honeybee losses (colony collapse disorder) have been reported; however, there remains no clear explanation for these colony losses, with parasitic mites, viruses, bacteria, and fungal diseases all being proposed as possible candidates. Common characteristics that most failing colonies share is a lack of overt disease symptoms and the disappearance of workers from what appears to be normally functioning colonies. In this study, we used quantitative PCR to monitor the presence of three honeybee viruses, deformed wing virus (DWV), acute bee paralysis virus (ABPV), and black queen cell virus (BQCV), during a 1-year period in 15 asymptomatic, varroa mite-positive honeybee colonies in Southern England, and 3 asymptomatic colonies confirmed to be varroa mite free. All colonies with varroa mites underwent control treatments to ensure that mite populations remained low throughout the study. Despite this, multiple virus infections were detected, yet a significant correlation was observed only between DWV viral load and overwintering colony losses. The long-held view has been that DWV is relatively harmless to the overall health status of honeybee colonies unless it is in association with severe varroa mite infestations. Our findings suggest that DWV can potentially act independently of varroa mites to bring about colony losses. Therefore, DWV may be a major factor in overwintering colony losses.

  3. Production of recombinant human granulocyte macrophage-colony stimulating factor in rice cell suspension culture with a human-like N-glycan structure.

    Science.gov (United States)

    Shin, Yun-Ji; Chong, Yun-Jo; Yang, Moon-Sik; Kwon, Tae-Ho

    2011-12-01

    The rice α-amylase 3D promoter system, which is activated under sucrose-starved conditions, has emerged as a useful system for producing recombinant proteins. However, using rice as the production system for therapeutic proteins requires modifications of the N-glycosylation pattern because of the potential immunogenicity of plant-specific sugar residues. In this study, glyco-engineered rice were generated as a production host for therapeutic glycoproteins, using RNA interference (RNAi) technology to down-regulate the endogenous α-1,3-fucosyltransferase (α-1,3-FucT) and β-1,2-xylosyltransferase (β-1,2-XylT) genes. N-linked glycans from the RNAi lines were identified, and their structures were compared with those isolated from a wild-type cell suspension. The inverted-repeat chimeric RNA silencing construct of α-1,3-fucosyltransferase and β-1,2-xylosyltransferase (Δ3FT/XT)-9 glyco-engineered line with significantly reduced core α-1,3-fucosylated and/or β-1,2-xylosylated glycan structures was established. Moreover, levels of plant-specific α-1,3-fucose and/or β-1,2-xylose residues incorporated into recombinant human granulocyte/macrophage colony-stimulating factor (hGM-CSF) produced from the N44 + Δ3FT/XT-4 glyco-engineered line co-expressing ihpRNA of Δ3FT/XT and hGM-CSF were significantly decreased compared with those in the previously reported N44-08 transgenic line expressing hGM-CSF. None of the glyco-engineered lines differed from the wild type with respect to cell division, proliferation or ability to secrete proteins into the culture medium. © 2011 The Authors. Plant Biotechnology Journal © 2011 Society for Experimental Biology, Association of Applied Biologists and Blackwell Publishing Ltd.

  4. How did Europe Rule Africa? Dialectics of Colonialism and African ...

    African Journals Online (AJOL)

    The question of how Europe ruled Africa relates to the crucial issues of settlernative identity as constructions of colonialism as well as political consciousness formation and development among the colonized as well as the colonizers. Because colonialism operated ambiguously throughout its life to the extent of hiding its ...

  5. Enhancement of erythroid colony growth in culture by hemin

    International Nuclear Information System (INIS)

    Porter, P.N.; Meints, R.H.; Mesner, K.

    1979-01-01

    Hemin was found to enhance the growth of murine erythroid colonies in culture. In the presence of 100 mU/ml erythropoietin (EPO), the addition of hemin (0.05-0.2 mM) resulted in the growth of twice as many colonies as were obtained with EPO alone. Hemin also significantly increased erythroid colony formation in culture in the absence of added EPO. Hemoblobin synthesis as measured by the incorporation of 59 Fe into cyclohexanone extractable heme was augmented in culture by hemin. Neither Δ-aminolevulinic acid, a hemin precursor, nor FeCl 3 increased colony number. (author)

  6. Beyond CD34+ cell dose: impact of method of peripheral blood hematopoietic stem cell mobilization (granulocyte-colony-stimulating factor [G-CSF], G-CSF plus plerixafor, or cyclophosphamide G-CSF/granulocyte-macrophage [GM]-CSF) on number of colony-forming unit-GM, engraftment, and Day +100 hematopoietic graft function.

    Science.gov (United States)

    Alexander, Erin T; Towery, Jeanne A; Miller, Ashley N; Kramer, Cindy; Hogan, Kathy R; Squires, Jerry E; Stuart, Robert K; Costa, Luciano J

    2011-09-01

    The dose of CD34+ cells/kg in the mobilized peripheral blood product is the main determinant of neutrophil and platelet (PLT) engraftment after autologous hematopoietic stem cell transplantation (AHSCT). Whether the method of mobilization, namely, granulocyte-colony-stimulating factor (G-CSF) alone (G), G-CSF plus plerixafor (G+P), or cyclophosphamide + G/granulocyte-macrophage (GM)-CSF (Cy+G/GM), independently affects number of colony-forming unit (CFU)-GM, engraftment, and hematopoietic graft function is unknown. We used a database of AHSCT patients with multiple myeloma or lymphoma to identify three groups with different mobilization strategies receiving transplantation with similar CD34+ cell doses. Groups were compared in terms of CFU-GM, ratio of CFU-GM/CD34+, engraftment of neutrophils and PLTs, and hematopoietic graft function on Day +100. Ninety-six patients were included in the analysis, 26 G, 32 G+P, and 38 Cy+G/GM, with median cell doses of 4.21 × 10(6) , 4.11 × 10(6) , and 4.67 × 10(6) CD34+/kg, respectively (p = 0.433). There was no significant difference in number of CFU-GM between the three groups; however, the ratio of CFU-GM/CD34+ was significantly lower for G+P (p = 0.008). Median time for neutrophil engraftment was 13 days in G+P and 12 days in G and Cy+G/GM (p = 0.028), while PLT engraftment happened at a median of 14.5 days in G+P versus 12 days in G and 11 days in Cy+G/GM (p = 0.012). There was no difference in hematopoietic graft function at Day +100. Plerixafor-based mobilization is associated with slightly reduced number of CFU-GM and minimal delay in engraftment that is independent of CD34+ cell dose. Hematopoietic graft function on Day 100 is not affected by mobilization strategy. © 2011 American Association of Blood Banks.

  7. Myotube formation is affected by adipogenic lineage cells in a cell-to-cell contact-independent manner

    International Nuclear Information System (INIS)

    Takegahara, Yuki; Yamanouchi, Keitaro; Nakamura, Katsuyuki; Nakano, Shin-ichi; Nishihara, Masugi

    2014-01-01

    Intramuscular adipose tissue (IMAT) formation is observed in some pathological conditions such as Duchenne muscular dystrophy (DMD) and sarcopenia. Several studies have suggested that IMAT formation is not only negatively correlated with skeletal muscle mass but also causes decreased muscle contraction in sarcopenia. In the present study, we examined w hether adipocytes affect myogenesis. For this purpose, skeletal muscle progenitor cells were transfected with siRNA of PPARγ (siPPARγ) in an attempt to inhibit adipogenesis. Myosin heavy chain (MHC)-positive myotube formation was promoted in cells transfected with siPPARγ compared to that of cells transfected with control siRNA. To determine whether direct cell-to-cell contact between adipocytes and myoblasts is a prerequisite for adipocytes to affect myogenesis, skeletal muscle progenitor cells were cocultured with pre- or mature adipocytes in a Transwell coculture system. MHC-positive myotube formation was inhibited when skeletal muscle progenitor cells were cocultured with mature adipocytes, but was promoted when they were cocultured with preadipocytes. Similar effects were observed when pre- or mature adipocyte-conditioned medium was used. These results indicate that preadipocytes play an important role in maintaining skeletal muscle mass by promoting myogenesis; once differentiated, the resulting mature adipocytes negatively affect myogenesis, leading to the muscle deterioration observed in skeletal muscle pathologies. - Highlights: • We examined the effects of pre- and mature adipocytes on myogenesis in vitro. • Preadipocytes and mature adipocytes affect myoblast fusion. • Preadipocytes play an important role in maintaining skeletal muscle mass. • Mature adipocytes lead to muscle deterioration observed in skeletal muscle pathologies

  8. Myotube formation is affected by adipogenic lineage cells in a cell-to-cell contact-independent manner

    Energy Technology Data Exchange (ETDEWEB)

    Takegahara, Yuki; Yamanouchi, Keitaro, E-mail: akeita@mail.ecc.u-tokyo.ac.jp; Nakamura, Katsuyuki; Nakano, Shin-ichi; Nishihara, Masugi

    2014-05-15

    Intramuscular adipose tissue (IMAT) formation is observed in some pathological conditions such as Duchenne muscular dystrophy (DMD) and sarcopenia. Several studies have suggested that IMAT formation is not only negatively correlated with skeletal muscle mass but also causes decreased muscle contraction in sarcopenia. In the present study, we examined w hether adipocytes affect myogenesis. For this purpose, skeletal muscle progenitor cells were transfected with siRNA of PPARγ (siPPARγ) in an attempt to inhibit adipogenesis. Myosin heavy chain (MHC)-positive myotube formation was promoted in cells transfected with siPPARγ compared to that of cells transfected with control siRNA. To determine whether direct cell-to-cell contact between adipocytes and myoblasts is a prerequisite for adipocytes to affect myogenesis, skeletal muscle progenitor cells were cocultured with pre- or mature adipocytes in a Transwell coculture system. MHC-positive myotube formation was inhibited when skeletal muscle progenitor cells were cocultured with mature adipocytes, but was promoted when they were cocultured with preadipocytes. Similar effects were observed when pre- or mature adipocyte-conditioned medium was used. These results indicate that preadipocytes play an important role in maintaining skeletal muscle mass by promoting myogenesis; once differentiated, the resulting mature adipocytes negatively affect myogenesis, leading to the muscle deterioration observed in skeletal muscle pathologies. - Highlights: • We examined the effects of pre- and mature adipocytes on myogenesis in vitro. • Preadipocytes and mature adipocytes affect myoblast fusion. • Preadipocytes play an important role in maintaining skeletal muscle mass. • Mature adipocytes lead to muscle deterioration observed in skeletal muscle pathologies.

  9. Involvement of membrane potential in alkaline band formation by internodal cells of Chara corallina.

    Science.gov (United States)

    Shimmen, Teruo; Wakabayashi, Akiko

    2008-10-01

    Internodal cells of Chara corallina form alkaline bands on their surface upon illumination via photosynthesis. In the present study, the effect of KCl on alkaline band formation was analyzed. When the extracellular KCl concentration was increased, alkaline band formation was extensively inhibited. Electrophysiological analysis unequivocally showed the need for inner negative membrane potential for alkaline band formation.

  10. Cutting edge: Bcl6-interacting corepressor contributes to germinal center T follicular helper cell formation and B cell helper function.

    Science.gov (United States)

    Yang, Jessica A; Tubo, Noah J; Gearhart, Micah D; Bardwell, Vivian J; Jenkins, Marc K

    2015-06-15

    CD4(+) germinal center (GC)-T follicular helper (Tfh) cells help B cells become long-lived plasma cells and memory cells. The transcriptional repressor Bcl6 plays a key role in GC-Tfh formation by inhibiting the expression of genes that promote differentiation into other lineages. We determined whether BCOR, a component of a Polycomb repressive complex that interacts with the Bcl6 BTB domain, influences GC-Tfh differentiation. T cell-targeted BCOR deficiency led to a substantial loss of peptide:MHC class II-specific GC-Tfh cells following Listeria monocytogenes infection and a 2-fold decrease following immunization with a peptide in CFA. The reduction in GC-Tfh cells was associated with diminished plasma cell and GC B cell formation. Thus, T cell-expressed BCOR is critical for optimal GC-Tfh cell differentiation and humoral immunity. Copyright © 2015 by The American Association of Immunologists, Inc.

  11. Macrophage conditioned medium induced cellular network formation in MCF-7 cells through enhanced tunneling nanotube formation and tunneling nanotube mediated release of viable cytoplasmic fragments

    Energy Technology Data Exchange (ETDEWEB)

    Patheja, Pooja, E-mail: pooja.patheja8@gmail.com [Laser Biomedical Applications Section, Raja Ramanna Centre for Advanced Technology, Indore 452013, Madhya Pradesh (India); Homi Bhabha National Institute, Training School Complex, Anushaktinagar, Mumbai 400094, Maharashtra (India); Sahu, Khageswar [Laser Biomedical Applications Section, Raja Ramanna Centre for Advanced Technology, Indore 452013, Madhya Pradesh (India)

    2017-06-15

    Infiltrating macrophages in tumor microenvironment, through their secreted cytokines and growth factors, regulate several processes of cancer progression such as cancer cell survival, proliferation, invasion, metastasis and angiogenesis. Recently, intercellular cytoplasmic bridges between cancer cells referred as tunneling nanotubes (TNTs) have been recognized as novel mode of intercellular communication between cancer cells. In this study, we investigated the effect of inflammatory mediators present in conditioned medium derived from macrophages on the formation of TNTs in breast adenocarcinoma cells MCF-7. Results show that treatment with macrophage conditioned medium (MφCM) not only enhanced TNT formation between cells but also stimulated the release of independently migrating viable cytoplasmic fragments, referred to as microplasts, from MCF-7 cells. Time lapse microscopy revealed that microplasts were released from parent cancer cells in extracellular space through formation of TNT-like structures. Mitochondria, vesicles and cytoplasm could be transferred from parent cell body to microplasts through connecting TNTs. The microplasts could also be resorbed into the parent cell body by retraction of the connecting TNTs. Microplast formation inhibited in presence cell migration inhibitor, cytochalasin-B. Notably by utilizing migratory machinery within microplasts, distantly located MCF-7 cells formed several TNT based intercellular connections, leading to formation of physically connected network of cells. Together, these results demonstrate novel role of TNTs in microplast formation, novel modes of TNT formation mediated by microplasts and stimulatory effect of MφCM on cellular network formation in MCF-7 cells mediated through enhanced TNT and microplast formation.

  12. The fate of Osterix-expressing mesenchymal cells in dental root formation and maintenance.

    Science.gov (United States)

    Takahashi, A; Ono, N; Ono, W

    2017-06-01

    Osterix (Osx)-expressing mesenchymal cells are progenitors for tooth root forming cells. The aim of this study was to reveal the fates of Osx-expressing cells during and after root formation using a lineage tracing experiment. To reveal the fates of Osx-expressing dental mesenchymal progenitors, we took advantage of tamoxifen-inducible Cre reporter system. Osx-creER; R26R-tdTomato mice received tamoxifen (0.1 mg/body) at postnatal day 3 (P3). In this system, Osx-expressing at P3 (Osx-P3) cells undergo recombination, and they and their descendants continue to express Tomato red fluorescence protein permanently. Mandibles were dissected at serial time points ranging from P4 to P116 to investigate how Osx-P3 cells participated in root formation. Tomato + cells on frozen sections were imaged under fluorescence microscopy. Osx-P3 cells and their descendants differentiated into all kinds of cells that contributed to the root and periodontal tissues, such as odontoblasts, cementoblasts, alveolar bone osteoblasts and periodontal ligament (PDL) cells during root formation. Even after root formation was completed, they persisted in dental pulp and PDL to provide progenitor cells for odontoblasts and cementoblasts. Osx-expressing cells play important roles in the entire processes of tooth root formation; their progeny continue to contribute to maintenance of tooth root even after root formation is complete. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  13. Unopposed production of granulocyte-macrophage colony-stimulating factor by tumors inhibits CD8+ T cell responses by dysregulating antigen-presenting cell maturation.

    Science.gov (United States)

    Bronte, V; Chappell, D B; Apolloni, E; Cabrelle, A; Wang, M; Hwu, P; Restifo, N P

    1999-05-15

    Tumor cells gene-modified to produce GM-CSF potently stimulate antitumor immune responses, in part, by causing the growth and differentiation of dendritic cells (DC). However, GM-CSF-modified tumor cells must be gamma-irradiated or they will grow progressively, killing the host. We observed that 23 of 75 (31%) human tumor lines and two commonly used mouse tumor lines spontaneously produced GM-CSF. In mice, chronic GM-CSF production by tumors suppressed Ag-specific CD8+ T cell responses. Interestingly, an inhibitory population of adherent CD11b(Mac-1)/Gr-1 double-positive cells caused the observed impairment of CD8+ T cell function upon direct cell-to-cell contact. The inhibitory cells were positive for some markers associated with Ag presenting cells, like F4/80, but were negative for markers associated with fully mature DC like DEC205, B7. 2, and MHC class II. We have previously reported that a similar or identical population of inhibitory "immature" APC was elicited after immunization with powerful recombinant immunogens. We show here that these inhibitory cells can be elicited by the administration of recombinant GM-CSF alone, and, furthermore, that they can be differentiated ex vivo into "mature" APC by the addition of IL-4 and GM-CSF. Thus, tumors may be able to escape from immune detection by producing "unopposed" GM-CSF, thereby disrupting the balance of cytokines needed for the maturation of fully functional DC. Further, CD11b/Gr-1 double-positive cells may function as "inhibitory" APC under the influence of GM-CSF alone.

  14. Unopposed Production of Granulocyte-Macrophage Colony-Stimulating Factor by Tumors Inhibits CD8+ T Cell Responses by Dysregulating Antigen-Presenting Cell Maturation1

    Science.gov (United States)

    Bronte, Vincenzo; Chappell, Dale B.; Apolloni, Elisa; Cabrelle, Anna; Wang, Michael; Hwu, Patrick; Restifo, Nicholas P.

    2008-01-01

    Tumor cells gene-modified to produce GM-CSF potently stimulate antitumor immune responses, in part, by causing the growth and differentiation of dendritic cells (DC). However, GM-CSF-modified tumor cells must be γ-irradiated or they will grow progressively, killing the host. We observed that 23 of 75 (31%) human tumor lines and two commonly used mouse tumor lines spontaneously produced GM-CSF. In mice, chronic GM-CSF production by tumors suppressed Ag-specific CD8+ T cell responses. Interestingly, an inhibitory population of adherent CD11b(Mac-1)/Gr-1 double-positive cells caused the observed impairment of CD8+ T cell function upon direct cell-to-cell contact. The inhibitory cells were positive for some markers associated with Ag presenting cells, like F4/80, but were negative for markers associated with fully mature DC like DEC205, B7.2, and MHC class II. We have previously reported that a similar or identical population of inhibitory “immature” APC was elicited after immunization with powerful recombinant immunogens. We show here that these inhibitory cells can be elicited by the administration of recombinant GM-CSF alone, and, furthermore, that they can be differentiated ex vivo into “mature” APC by the addition of IL-4 and GM-CSF. Thus, tumors may be able to escape from immune detection by producing “unopposed” GM-CSF, thereby disrupting the balance of cytokines needed for the maturation of fully functional DC. Further, CD11b/Gr-1 double-positive cells may function as “inhibitory” APC under the influence of GM-CSF alone. PMID:10229805

  15. Multinuclear giant cell formation is enhanced by down-regulation of Wnt signaling in gastric cancer cell line, AGS

    International Nuclear Information System (INIS)

    Kim, Shi-Mun; Kim, Rockki; Ryu, Jae-Hyun; Jho, Eek-Hoon; Song, Ki-Joon; Jang, Shyh-Ing; Kee, Sun-Ho

    2005-01-01

    AGS cells, which were derived from malignant gastric adenocarcinoma tissue, lack E-cadherin-mediated cell adhesion but have a high level of nuclear β-catenin, which suggests altered Wnt signal. In addition, approximately 5% of AGS cells form multinuclear giant cells in the routine culture conditions, while taxol treatment causes most AGS cells to become giant cells. The observation of reduced nuclear β-catenin levels in giant cells induced by taxol treatment prompted us to investigate the relationship between Wnt signaling and giant cell formation. After overnight serum starvation, the shape of AGS cells became flattened, and this morphological change was accompanied by decrease in Myc expression and an increase in the giant cell population. Lithium chloride treatment, which inhibits GSK3β activity, reversed these serum starvation effects, which suggests an inverse relationship between Wnt signaling and giant cell formation. Furthermore, the down-regulation of Wnt signaling caused by the over-expression of ICAT, E-cadherin, and Axin enhanced giant cell formation. Therefore, down-regulation of Wnt signaling may be related to giant cell formation, which is considered to be a survival mechanism against induced cell death

  16. Dynamic Network Formation Using Ant Colony Optimization

    Science.gov (United States)

    2009-03-01

    Problem (DVRP) ............................................ 36 2.7.2 Dynamic Traveling Salesman Problem (DTSP) ....................................... 41...47 2.8.3 Distributed Traveling Salesman Problem ................................................. 48 2.8.4 FIRE Ant...uses the fixed cost of the network in its calculation and commodities are not included in the problem formulation . Using a probabilistic undirected

  17. Unopposed Production of Granulocyte-Macrophage Colony-Stimulating Factor by Tumors Inhibits CD8+ T Cell Responses by Dysregulating Antigen-Presenting Cell Maturation1

    OpenAIRE

    Bronte, Vincenzo; Chappell, Dale B.; Apolloni, Elisa; Cabrelle, Anna; Wang, Michael; Hwu, Patrick; Restifo, Nicholas P.

    1999-01-01

    Tumor cells gene-modified to produce GM-CSF potently stimulate antitumor immune responses, in part, by causing the growth and differentiation of dendritic cells (DC). However, GM-CSF-modified tumor cells must be γ-irradiated or they will grow progressively, killing the host. We observed that 23 of 75 (31%) human tumor lines and two commonly used mouse tumor lines spontaneously produced GM-CSF. In mice, chronic GM-CSF production by tumors suppressed Ag-specific CD8+ T cell responses. Interesti...

  18. Colony Collapse Disorder

    Science.gov (United States)

    In CCD, the majority of worker bees in a colony disappear and leave behind a queen, plenty of food and a few nurse bees to care for remaining immature bees and the queen. EPA and USDA are working to understand this problem.

  19. Colonial American Astronomy

    Science.gov (United States)

    Yeomans, Donald K.

    2007-12-01

    While a foundation of German scientific methods enabled the rapid growth of North American Astronomy in the nineteenth century, during the seventeenth and most of the eighteenth centuries, the colonial men of science looked only to the English mother country for scientific patronage and guidance. An essay on fundamental astronomy appeared in one of the annual colonial almanacs as early as 1656, telescopic observations were made about 1660 and the first original colonial astronomical work was published by Thomas Danforth on the comet of 1664. By 1671 the Copernican ideas were so espoused at Harvard College that a physics class refused to read a Ptolemaic textbook when it was assigned to them by a senior instructor. At least in the Cambridge-Boston area, contemporary colonialist had access to the most recent scientific publications from the mother country. Observations of the great comet of 1680 by the Almanac maker, John Foster, reached Isaac Newton and were used and gratefully acknowledged in his Principia. During the seventeenth century the colonial interest in astronomy was more intense than it was for other sciences but colonists still occupied a position in the scientific backwater when compared with contemporary European scientists. Nevertheless, the science of astronomy was successfully transplanted from England to North America in the seventeenth century.

  20. BCL6 interacting corepressor contributes to germinal center T follicular helper cell formation and B cell helper function

    Science.gov (United States)

    Yang, Jessica A.; Tubo, Noah J.; Gearhart, Micah D.; Bardwell, Vivian J.; Jenkins, Marc K.

    2015-01-01

    CD4+ germinal center (GC) T follicular helper (GC-Tfh) cells help B cells become long-lived plasma cells and memory cells. The transcriptional repressor BCL6 plays a key role in GC-Tfh formation by inhibiting the expression of genes that promote differentiation into other lineages. We determined whether BCOR, a component of a Polycomb repressive complex that interacts with the BCL6 BTB domain, influences GC-Tfh differentiation. T cell-targeted BCOR deficiency led to a substantial loss of peptide:MHCII-specific GC-Tfh cells following Listeria monocytogenes infection and a 2-fold decrease following immunization with a peptide in CFA. The reduction in GC-Tfh cells was associated with diminished plasma cell and GC B cell formation. Thus, T cell-expressed BCOR is critical for optimal GC-Tfh differentiation and humoral immunity. PMID:25964495

  1. Stem cell mobilization induced by subcutaneous granulocyte-colony stimulating factor to improve cardiac regeneration after acute ST-elevation myocardial infarction: result of the double-blind, randomized, placebo-controlled stem cells in myocardial infarction (STEMMI) trial

    DEFF Research Database (Denmark)

    Ripa, Rasmus Sejersten; Jørgensen, Erik; Wang, Yongzhong

    2006-01-01

    BACKGROUND: Phase 1 clinical trials of granulocyte-colony stimulating factor (G-CSF) treatment after myocardial infarction have indicated that G-CSF treatment is safe and may improve left ventricular function. This randomized, double-blind, placebo-controlled trial aimed to assess the efficacy......: Bone marrow stem cell mobilization with subcutaneous G-CSF is safe but did not lead to further improvement in ventricular function after acute myocardial infarction compared with the recovery observed in the placebo group....... measured by both MRI (8.5 versus 8.0; P=0.9) and echocardiography (5.7 versus 3.7; P=0.7). The risk of severe clinical adverse events was not increased by G-CSF. In addition, in-stent late lumen loss and target vessel revascularization rate in the follow-up period were similar in the 2 groups. CONCLUSIONS...

  2. Cdc42 is not essential for filopodium formation, directed migration, cell polarization, and mitosis in fibroblastoid cells

    DEFF Research Database (Denmark)

    Czuchra, Aleksandra; Wu, Xunwei; Meyer, Hannelore

    2005-01-01

    Cdc42 is a small GTPase involved in the regulation of the cytoskeleton and cell polarity. To test whether Cdc42 has an essential role in the formation of filopodia or directed cell migration, we generated Cdc42-deficient fibroblastoid cells by conditional gene inactivation. We report here that loss...... of Cdc42 did not affect filopodium or lamellipodium formation and had no significant influence on the speed of directed migration nor on mitosis. Cdc42-deficient cells displayed a more elongated cell shape and had a reduced area. Furthermore, directionality during migration and reorientation of the Golgi...... apparatus into the direction of migration was decreased. However, expression of dominant negative Cdc42 in Cdc42-null cells resulted in strongly reduced directed migration, severely reduced single cell directionality, and complete loss of Golgi polarization and of directionality of protrusion formation...

  3. Different tolerances to chemical contaminants between unicellular and colonial morph of Microcystis aeruginosa: excluding the differences among different strains.

    Science.gov (United States)

    Li, Ming; Nkrumah, Philip Nti; Peng, Qiang

    2015-03-21

    In order to ascertain the different tolerances to chemical contaminants in one strain of Microcystis with different morphology, unicellular and colonial Microcystis in one strain was obtained from different conditions of light intensity and temperature. The samples were divided into 8 groups including control (no chemical addition), CuSO4, chloromycetin, and linear alkylbenzene sulfonatelas (LAS) treatments. The cell density, cell viability, superoxide dismutase (SOD), and malonaldehyde of Microcystis were analyzed. It was observed that cell density of both unicellular and colonial Microcystis increased from the beginning to day-5 in the control and the CuSO4 treatments. However, the growth of Microcystis was significantly inhibited in the culture with chloromycetin and LAS treatments. Notably, the inhibition rate was significantly high in unicellular Microcystis relative to the colonial Microcystis. The esterase activity in all the treatments decreased dramatically relating to the control. In addition, the esterase activity in colonial Microcystis was significantly higher than that of the unicellular Microcystis in all the treatments. Although there were no significant differences in activities of SOD between the two morphologies in the control treatments, in all the other treatments, significant differences were observed. The results proved that colony formation of Microcystis could be considered as a strategy in response to chemical stress. Copyright © 2014 Elsevier B.V. All rights reserved.

  4. Cell-size distribution in epithelial tissue formation and homeostasis.

    Science.gov (United States)

    Puliafito, Alberto; Primo, Luca; Celani, Antonio

    2017-03-01

    How cell growth and proliferation are orchestrated in living tissues to achieve a given biological function is a central problem in biology. During development, tissue regeneration and homeostasis, cell proliferation must be coordinated by spatial cues in order for cells to attain the correct size and shape. Biological tissues also feature a notable homogeneity of cell size, which, in specific cases, represents a physiological need. Here, we study the temporal evolution of the cell-size distribution by applying the theory of kinetic fragmentation to tissue development and homeostasis. Our theory predicts self-similar probability density function (PDF) of cell size and explains how division times and redistribution ensure cell size homogeneity across the tissue. Theoretical predictions and numerical simulations of confluent non-homeostatic tissue cultures show that cell size distribution is self-similar. Our experimental data confirm predictions and reveal that, as assumed in the theory, cell division times scale like a power-law of the cell size. We find that in homeostatic conditions there is a stationary distribution with lognormal tails, consistently with our experimental data. Our theoretical predictions and numerical simulations show that the shape of the PDF depends on how the space inherited by apoptotic cells is redistributed and that apoptotic cell rates might also depend on size. © 2017 The Author(s).

  5. Aggregate formation affects ultrasonic disruption of microalgal cells.

    Science.gov (United States)

    Wang, Wei; Lee, Duu-Jong; Lai, Juin-Yih

    2015-12-01

    Ultrasonication is a cell disruption process of low energy efficiency. This study dosed K(+), Ca(2+) and Al(3+) to Chlorella vulgaris cultured in Bold's Basal Medium at 25°C and measured the degree of cell disruption under ultrasonication. Adding these metal ions yielded less negatively charged surfaces of cells, while with the latter two ions large and compact cell aggregates were formed. The degree of cell disruption followed: control=K(+)>Ca(2+)>Al(3+) samples. Surface charges of cells and microbubbles have minimal effects on the microbubble number in the proximity of the microalgal cells. Conversely, cell aggregates with large size and compact interior resist cell disruption under ultrasonication. Staining tests revealed high diffusional resistance of stains over the aggregate interior. Microbubbles may not be effective generated and collapsed inside the compact aggregates, hence leading to low cell disruption efficiencies. Effective coagulation/flocculation in cell harvesting may lead to adverse effect on subsequent cell disruption efficiency. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Lysophosphatidic acid directly induces macrophage-derived foam cell formation by blocking the expression of SRBI.

    Science.gov (United States)

    Chen, Linmu; Zhang, Jun; Deng, Xiao; Liu, Yan; Yang, Xi; Wu, Qiong; Yu, Chao

    2017-09-23

    The leading cause of morbidity and mortality is the result of cardiovascular disease, mainly atherosclerosis. The formation of macrophage foam cells by ingesting ox-LDL and focal retention in the subendothelial space are the hallmarks of the early atherosclerotic lesion. Lysophosphatidic acid (LPA), which is a low-molecular weight lysophospholipid enriched in oxidized LDL, exerts a range of effects on the cardiovascular system. Previous reports show that LPA increases the uptake of ox-LDL to promote the formation of foam cells. However, as the most active component of ox-LDL, there is no report showing whether LPA directly affects foam cell formation. The aim of this study was to investigate the effects of LPA on foam cell formation, as well as to elucidate the underlying mechanism. Oil red O staining and a Cholesterol/cholesteryl ester quantitation assay were used to evaluate foam cell formation in Raw264.7 macrophage cells. We utilized a Western blot and RT-PCR to investigate the relationship between LPA receptors and lipid transport related proteins. We found that LPA promoted foam cell formation, using 200 μM for 24 h. Meanwhile, the expression of the Scavenger receptor BI (SRBI), which promotes the efflux of free cholesterol, was decreased. Furthermore, the LPA 1/3 receptor antagonist Ki16425 significantly abolished the LPA effects, indicating that LPA 1/3 was involved in the foam cell formation and SRBI expression induced by LPA. Additionally, the LPA-induced foam cell formation was blocked with an AKT inhibitor. Our results suggest that LPA-enhanced foam cell formation is mediated by LPA 1/3 -AKT activation and subsequent SRBI expression. Copyright © 2017. Published by Elsevier Inc.

  7. Hematopoietic stem cell mobilizing agents G-CSF, cyclophosphamide or AMD3100 have distinct mechanisms of action on bone marrow HSC niches and bone formation.

    Science.gov (United States)

    Winkler, I G; Pettit, A R; Raggatt, L J; Jacobsen, R N; Forristal, C E; Barbier, V; Nowlan, B; Cisterne, A; Bendall, L J; Sims, N A; Lévesque, J-P

    2012-07-01

    The CXCR4 antagonist AMD3100 is progressively replacing cyclophosphamide (CYP) as adjuvant to granulocyte colony-stimulating factor (G-CSF) to mobilize hematopoietic stem cells (HSC) for autologous transplants in patients who failed prior mobilization with G-CSF alone. It has recently emerged that G-CSF mediates HSC mobilization and inhibits bone formation via specific bone marrow (BM) macrophages. We compared the effect of these three mobilizing agents on BM macrophages, bone formation, osteoblasts, HSC niches and HSC reconstitution potential. Both G-CSF and CYP suppressed niche-supportive macrophages and osteoblasts, and inhibited expression of endosteal cytokines resulting in major impairment of HSC reconstitution potential remaining in the mobilized BM. In sharp contrast, although AMD3100 was effective at mobilizing HSC, it did not suppress osteoblasts, endosteal cytokine expression or reconstitution potential of HSC remaining in the mobilized BM. In conclusion, although G-CSF, CYP and AMD3100 efficiently mobilize HSC into the blood, their effects on HSC niches and bone formation are distinct with both G-CSF and CYP targeting HSC niche function and bone formation, whereas AMD3100 directly targets HSC without altering niche function or bone formation.

  8. Effects of irradiated biodegradable polymer in endothelial cell monolayer formation

    Energy Technology Data Exchange (ETDEWEB)

    Arbeitman, Claudia R.; Grosso, Mariela F. del [CONICET – Consejo Nacional de Investigaciones Científicas y Técnicas (Argentina); Gerencia de Investigación y Aplicaciones, TANDAR-CNEA (Argentina); Behar, Moni [Instituto de Física, UFRGS, Porto Alegre, RS (Brazil); García Bermúdez, Gerardo, E-mail: ggb@tandar.cnea.gov.ar [CONICET – Consejo Nacional de Investigaciones Científicas y Técnicas (Argentina); Gerencia de Investigación y Aplicaciones, TANDAR-CNEA (Argentina); Escuela de Ciencia y Tecnología, UNSAM (Argentina)

    2013-11-01

    In this work we study cell adhesion, proliferation and cell morphology of endothelial cell cultured on poly-L-lactide acid (PLLA) modified by heavy ion irradiation. Thin films of PLLA samples were irradiated with sulfur (S) at energies of 75 MeV and gold (Au) at 18 MeV ion-beams. Ion beams were provided by the Tandar (Buenos Aires, Argentina) and Tandetron (Porto Alegre, Brazil) accelerators, respectively. The growth of a monolayer of bovine aortic endothelial cells (BAEC) onto unirradiated and irradiated surfaces has been studied by in vitro techniques in static culture. Cell viability and proliferation increased on modified substrates. But the results on unirradiated samples, indicate cell death (necrosis/apoptosis) with the consequent decrease in proliferation. We analyzed the correlation between irradiation parameters and cell metabolism and morphology.

  9. Hypochlorite- and hypobromite-mediated radical formation and its role in cell lysis

    DEFF Research Database (Denmark)

    Hawkins, C L; Brown, B E; Davies, Michael Jonathan

    2001-01-01

    trapping, and it is shown that reaction of both oxidants with each cell type generates cell-derived radicals. Red blood cells exposed to nonlytic doses of HOCl generate novel nitrogen-centered radicals whose formation is GSH dependent. In contrast, HOBr gives rise to nitrogen-centered, membrane....... In this study it is shown that HOBr induces red blood cell lysis at approximately 10-fold lower concentrations than HOCl, whereas with monocyte (THP1) and macrophage (J774) cells HOCl and HOBr induce lysis at similar concentrations. The role of radical formation during lysis has been investigated by EPR spin......-derived protein radicals. With lytic doses of either oxidant, protein (probably hemoglobin)-derived, nitrogen-centered radicals are observed. Unlike the red blood cells, treatment of monocytes and macrophages with HOCl gives significant radical formation only under conditions where cell lysis occurs concurrently...

  10. On the formation of germ cells: The good, the bad and the ugly.

    Science.gov (United States)

    Chuva de Sousa Lopes, Susana M; Roelen, Bernard A J

    2010-03-01

    Mammalian germ cells are powerful cells, the only ones that transmit information to the next generation ensuring the continuation of the species. But "with great power, comes great responsibility", meaning that germ cells are only a few steps away from turning carcinogenic. Despite recent advances little is known about germ cell formation in mammals, predominantly because of the inaccessibility of these cells. Moreover, it is difficult to pin down what in essence is characteristic of a germ cell, as germ cells keep changing place, morphology, expression markers and epigenetic identity. Formation of (primordial) germ cells in primate ES cell cultures would therefore be helpful to identify molecular signalling pathways associated with germ cell differentiation and to study epigenetic changes in germ cells. In addition, the in vitro derivation of functional germ cells from ES cells could be used in combination with therapeutic cloning to generate patient-specific ES cell lines, and can have applications in animal breeding. In this review we present the state-of-the-art on how mouse and human germ cells are formed in vivo (the good), we discuss the link between germ cells, pluripotency and germ cell tumours (the bad) and show that despite continuous progress in trying to differentiate germ cells in vitro (the ugly) the generation of functional germ cells is still a real challenge. Copyright 2009 International Society of Differentiation. Published by Elsevier B.V. All rights reserved.

  11. Unmasking Cryptococcal Meningitis Immune Reconstitution Inflammatory Syndrome due to Granulocyte Colony-Stimulating Factor Use in a Patient with a Poorly Differentiated Germ Cell Neoplasm

    Directory of Open Access Journals (Sweden)

    Nathan C. Bahr

    2014-01-01

    Full Text Available Cryptococcal meningitis immune reconstitution inflammatory syndrome (IRIS is frequently seen in patients with HIV and less frequently in patients on immune suppressive medications for other conditions. Here, we describe the first reported case of unmasking cryptococcal IRIS due to granulocyte colony-stimulating factor used in an HIV-negative patient with chemotherapy-induced neutropenia.

  12. Formation and regulation of the cancer stem cell niche.

    Science.gov (United States)

    Takakura, Nobuyuki

    2012-07-01

    It is widely accepted that tumors contain cancer stem cells (CSC) possessing self-renewal potential as well as the ability to generate numerous cancer cells. Cancer stem cells are resistant to conventional cancer therapy and have greater invasive and metastatic behavior. It has been suggested that blood vessels provide a niche that maintains stemness in normal organs. This role also extends to the field of cancer biology. Cancer stem cells have been isolated from leukemias and solid cancers. Identification of these cells and their niche is critical for identifying molecular targets in order to inhibit their growth and to destroy their niche. For this purpose, sorting of living CSC is required to monitor their presence in the presumptive niche to establish whether a CSC candidate actually shows malignant features. Based on and referring to analyses in normal tissues, molecules including nitric oxide, Wnt, neuropilin-1, hepatocyte growth factor and others involved in the maintenance of CSC have been isolated. Stem cells might affect niche cells and niche cells produce stemness factors on such stimulation. Therefore, the niche might be flexible to support self-renewal or differentiation of stem cells even in the same niche cells. © 2012 Japanese Cancer Association.

  13. Stem cells catalyze cartilage formation by neonatal articular chondrocytes in 3D biomimetic hydrogels

    Science.gov (United States)

    Lai, Janice H.; Kajiyama, Glen; Smith, Robert Lane; Maloney, William; Yang, Fan

    2013-12-01

    Cartilage loss is a leading cause of disability among adults and effective therapy remains elusive. Neonatal chondrocytes (NChons) are an attractive allogeneic cell source for cartilage repair, but their clinical translation has been hindered by scarce donor availability. Here we examine the potential for catalyzing cartilage tissue formation using a minimal number of NChons by co-culturing them with adipose-derived stem cells (ADSCs) in 3D hydrogels. Using three different co-culture models, we demonstrated that the effects of co-culture on cartilage tissue formation are dependent on the intercellular distance and cell distribution in 3D. Unexpectedly, increasing ADSC ratio in mixed co-culture led to increased synergy between NChons and ADSCs, and resulted in the formation of large neocartilage nodules. This work raises the potential of utilizing stem cells to catalyze tissue formation by neonatal chondrocytes via paracrine signaling, and highlights the importance of controlling cell distribution in 3D matrices to achieve optimal synergy.

  14. Methanofullerene elongated nanostructure formation for enhanced organic solar cells

    International Nuclear Information System (INIS)

    Reyes-Reyes, M.; Lopez-Sandoval, R.; Arenas-Alatorre, J.; Garibay-Alonso, R.; Carroll, D.L.; Lastras-Martinez, A.

    2007-01-01

    Using transmission electron microscopy (TEM) and Z-contrast imaging we have demonstrated elongated nanostructure formation of fullerene derivative [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) within an organic host through annealing. The annealing provides an enhanced mobility of the PCBM molecules and, with good initial dispersion, allows for the formation of exaggerated grain growth within the polymer host. We have assembled these nanostructures within the regioregular conjugated polymer poly(3-hexylthiophene) (P3HT). This PCBM elongated nanostructure formation maybe responsible for the very high efficiencies observed, at very low loadings of PCBM (1:0.6, polymer to PCBM), in annealed photovoltaics. Moreover, our high resolution TEM and electron energy loss spectroscopy studies clearly show that the PCBM crystals remain crystalline and are unaffected by the 200-keV electron beam

  15. Methanofullerene elongated nanostructure formation for enhanced organic solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Reyes-Reyes, M. [Instituto de Investigacion en Comunicacion Optica, Universidad Autonoma de San Luis Potosi, Alvaro Obregon 64, San Luis Potosi (Mexico)], E-mail: reyesm@cactus.iico.uaslp.mx; Lopez-Sandoval, R. [Instituto Potosino de Investigacion Cientifica y Tecnologica, Camino a la presa San Jose 2055, CP 78216. San Luis Potosi (Mexico); Arenas-Alatorre, J. [Instituto de Fisica, UNAM, Apartado Postal 20-364, 01000, Mexico, D.F. (Mexico); Garibay-Alonso, R. [Instituto Potosino de Investigacion Cientifica y Tecnologica, Camino a la presa San Jose 2055, CP 78216. San Luis Potosi (Mexico); Carroll, D.L. [Center for Nanotechnology and Molecular Materials, Department of Physics. Wake Forest University, Winston-Salem NC 27109 (United States); Lastras-Martinez, A. [Instituto de Investigacion en Comunicacion Optica, Universidad Autonoma de San Luis Potosi, Alvaro Obregon 64, San Luis Potosi (Mexico)

    2007-11-01

    Using transmission electron microscopy (TEM) and Z-contrast imaging we have demonstrated elongated nanostructure formation of fullerene derivative [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) within an organic host through annealing. The annealing provides an enhanced mobility of the PCBM molecules and, with good initial dispersion, allows for the formation of exaggerated grain growth within the polymer host. We have assembled these nanostructures within the regioregular conjugated polymer poly(3-hexylthiophene) (P3HT). This PCBM elongated nanostructure formation maybe responsible for the very high efficiencies observed, at very low loadings of PCBM (1:0.6, polymer to PCBM), in annealed photovoltaics. Moreover, our high resolution TEM and electron energy loss spectroscopy studies clearly show that the PCBM crystals remain crystalline and are unaffected by the 200-keV electron beam.

  16. Effect of oxygen on formation of micronuclei and binucleated cells and cell survival in γ-irradiated 3T3 cells

    International Nuclear Information System (INIS)

    Zhang Peng; Zheng Xiulong

    1991-01-01

    Formation of micronuclei and binucleate cells and their relationships with cell survival were studied in the aerobically- and anaerobically-irradiated 3T3 cells. The results showed taht frequency of micronuclei, percentage of micronucleus cells and percentage of binucleate cells increased linearly with the radiation dose in certain range. Oxygen enhancement ratios (OER) of micronucleus frequency, percentage of micronucleus cells, percentage of binucleate cells and cell survival were 2.02, 1.96, 1.87 and 1.83 respectively. The percentage of micronucleus cells or the percentage of micronucleus cells plus binucleate cells correlated negatively well with cell survival. The mechanism of oxygen effect in the radiation response of 3T3 cells and the significance of formation of micronuclei and binucleate cells were discussed

  17. Statistical dynamics of spatial-order formation by communicating cells

    OpenAIRE

    Olimpio, Eduardo P.; Dang, Yiteng; Youk, Hyun

    2017-01-01

    Communicating cells can coordinate their gene expressions to form spatial patterns. 'Secrete-and-sense cells' secrete and sense the same molecule to do so and are ubiquitous. Here we address why and how these cells, from disordered beginnings, can form spatial order through a statistical mechanics-type framework for cellular communication. Classifying cellular lattices by 'macrostate' variables - 'spatial order paramete' and average gene-expression level - reveals a conceptual picture: cellul...

  18. Mathematical modeling of dormant cell formation in growing biofilm

    OpenAIRE

    Kotaro eChihara; Shinya eMatsumoto; Yuki eKagawa; Satoshi eTsuneda

    2015-01-01

    Understanding the dynamics of dormant cells in microbial biofilms, in which the bacteria are embedded in extracellular matrix, is important for developing successful antibiotic therapies against pathogenic bacteria. Although some of the molecular mechanisms leading to bacterial persistence have been speculated in planktonic bacterial cell, how dormant cells emerge in the biofilms of pathogenic bacteria such as Pseudomonas aeruginosa remains unclear. The present study proposes four hypotheses ...

  19. Formation and action of oxygen activated species in cell cultures

    International Nuclear Information System (INIS)

    Hoffmann, M.E.; Meneghini, R.

    1982-01-01

    The differences of hydrogen peroxide sensibility of mammal cell lineages (man, mouse, chinese hamster) in culture are studied. The cellular survival and the frequency of DNA induced breaks by hydrogen peroxide are analysed. The efficiency of elimination of DNA breaks by cells is determined. The possible relation between the cell capacity of repair and its survival to hydrogen peroxide action is also discussed. (M.A.) [pt

  20. Kant's Second Thoughts on Colonialism

    NARCIS (Netherlands)

    Kleingeld, Pauline; Flikschuh, Katrin; Ypi, Lea

    2014-01-01

    Kant is widely regarded as a fierce critic of colonialism. In Toward Perpetual Peace and the Metaphysics of Morals, for example, he forcefully condemns European conduct in the colonies as a flagrant violation of the principles of right. His earlier views on colonialism have not yet received much

  1. Recycling Colonial Cultural Heritage

    DEFF Research Database (Denmark)

    Johansson, Troels Degn

    2017-01-01

    Danish art collective Superflex’ project Porcelain Pirates for the Zeeuws Museum in Middelburg, the Netherlands, is a fascinating and complex example of how a museum collection of artefacts from a colonial past may gain critical new meaning by means of cultural production and curatorial strategy....... By means of a museum installation (Porcelain Pirates, Zeeuws Museum, 2009) and a popular TV-series (Porcelain, Propellerhead, 2010) produced in Vietnam by a Vietnamese production company, Superflex seeks to explore and question a complex piece of colonial history with an important Asian-European as well...... economic stimulus in the entire region and also provided diplomatic gifts that were used to cement the Dutch war of independence against Spain.” Authentic artefacts from San Jago were used as props in the TV-series produced in Vietnam and were subsequently included as artefacts in the installation...

  2. Recycling Colonial Cultural Heritage

    DEFF Research Database (Denmark)

    Johansson, Troels Degn

    2017-01-01

    Danish art collective Superflex’ project Porcelain Pirates for the Zeeuws Museum in Middelburg, the Netherlands, is a fascinating and complex example of how a museum collection of artefacts from a colonial past may gain critical new meaning by means of cultural production and curatorial strategy....... By means of a museum installation (Porcelain Pirates, Zeeuws Museum, 2009) and a popular TV-series (Porcelain, Propellerhead, 2010) produced in Vietnam by a Vietnamese production company, Superflex seeks to explore and question a complex piece of colonial history with an important Asian-European as well...... of the first consignment of South East Asian porcelain destined for the European market. San Jago’s cargo of porcelain was realized economically by a big auction in the Netherlands. According to the Museum and it’s installation, the “importance of this auction was unprecedented and it provided enormous...

  3. Programmed cell death for defense against anomaly and tumor formation

    International Nuclear Information System (INIS)

    Kondo, Sohei; Norimura, Toshiyuki; Nomura, Taisei

    1995-01-01

    Cell death after exposure to low-level radiation is often considered evidence that radiation is poisonous, however small the dose. Evidence has been accumulating to support the notion that cell death after low-level exposure to radiation results from activation of suicidal genes open-quote programmed cell death close-quote or open-quote apoptosis close-quote - for the health of the whole body. This paper gives experimental evidence that embryos of fruit flies and mouse fetuses have potent defense mechanisms against teratogenic or tumorigenic injury caused by radiation and carcinogens, which function through programmed cell death

  4. Hegel and Colonialism

    OpenAIRE

    Stone, Alison Laura

    2017-01-01

    This article explores the implications of Hegel’s Philosophy of World History with respect to colonialism. For Hegel, freedom can be recognized and practised only in classical, Christian and modern Europe; therefore, the world’s other peoples can acquire freedom only if Europeans impose their civilization upon them. Although this imposition denies freedom to colonized peoples, this denial is legitimate for Hegel because it is the sole condition on which these peoples can gain freedom in the l...

  5. All you can eat: is food supply unlimited in a colonially breeding bird?

    OpenAIRE

    Hoi, Herbert; Kri?tof?k, J?n; Darolov?, Al?beta

    2015-01-01

    Food availability is generally considered to determine breeding site selection and therefore plays an important role in hypotheses explaining the evolution of colony formation. Hypotheses trying to explain why birds join a colony usually assume that food is not limited, whereas those explaining variation in colony size suggest that food is under constraint. In this study, we investigate the composition and amount of food items not eaten by the nestlings and found in nest burrows of colonially...

  6. Xanthine Oxidase Induces Foam Cell Formation through LOX-1 and NLRP3 Activation.

    Science.gov (United States)

    Dai, Yao; Cao, Yongxiang; Zhang, Zhigao; Vallurupalli, Srikanth; Mehta, Jawahar L

    2017-02-01

    Xanthine oxidase catalyzes the oxidation of xanthine to uric acid. This process generates excessive reactive oxygen species (ROS) that play an important role in atherogenesis. Recent studies show that LRR and PYD domains-containing protein 3 (NLRP3), a component of the inflammasome, may be involved in the formation of foam cells, a hallmark of atherosclerosis. This study was designed to study the role of various scavenger receptors and NLRP3 inflammasome in xanthine oxidase and uric acid-induced foam cell formation. Human vascular smooth muscle cells (VSMCs) and THP-1 macrophages were treated with xanthine oxidase or uric acid. Xanthine oxidase treatment (of both VSMCs and THP-1 cells) resulted in foam cell formation in concert with generation of ROS and expression of cluster of differentiation 36 (CD36) and oxidized low density lipoprotein (lectin-like) receptor 1 (LOX-1), but not of scavenger receptor A (SRA). Uric acid treatment resulted in foam cell formation, ROS generation and expression of CD36, but not of LOX-1 or SRA. Further, treatment of cells with xanthine oxidase, but not uric acid, activated NLRP3 and its downstream pro-inflammatory signals- caspase-1, interleukin (IL)-1β and IL-18. Blockade of LOX-1 or NLRP3 inflammasome with specific siRNAs reduced xanthine oxidase-induced foam cell formation, ROS generation and activation of NLRP3 and downstream signals. Xanthine oxidase induces foam cell formation in large part through activation of LOX-1 - NLRP3 pathway in both VSMCs and THP-1 cells, but uric acid-induced foam cell formation is exclusively through CD36 pathway. Further, LOX-1 activation is upstream of NLRP3 activation. Graphical Abstract Steps in the formation of foam cells in response to xanthine oxidase and uric acid. Xanthine oxidase stimulates LOX-1 expression on the cell membrane of macrophages and vascular smooth muscle cells (VSMCs) and increases generation of ROS, which activate NLRP3 inflammasome and downstream pro

  7. Mesenchymal Stem Cells in Perichondrium Express Activated Leukocyte Cell Adhesion Molecule and Participate in Bone Marrow Formation

    Science.gov (United States)

    Arai, Fumio; Ohneda, Osamu; Miyamoto, Takeshi; Zhang, Xiu Qin; Suda, Toshio

    2002-01-01

    Perichondrium in fetal limb is composed of undifferentiated mesenchymal cells. However, the multipotency of cells in this region and the role of perichondrium in bone marrow formation are not well understood. In this report, we purified and characterized perichondrial cells using a monoclonal antibody against activated leukocyte cell adhesion molecule (ALCAM) and investigated the role of perichondrial cells in hematopoietic bone marrow formation. ALCAM is expressed on hematopoietic cells, endothelial cells, bone marrow stromal cells, and mesenchymal stem cells and mediates homophilic (ALCAM–ALCAM)/heterophilic (ALCAM-CD6) cell adhesion. Here we show by immunohistochemical staining that ALCAM is expressed in perichondrium. ALCAM+ perichondrial cells isolated by FACS® exhibit the characteristics of mesenchymal stem cells. ALCAM+ cells can differentiate into osteoblasts, adipocytes, chondrocytes, and stromal cells, which can support osteoclastogenesis, hematopoiesis, and angiogenesis. Furthermore, the addition of ALCAM-Fc or CD6-Fc to the metatarsal culture, the invasion of the blood vessels to a cartilage was inhibited. Our findings indicate that ALCAM+ perichondrial cells participate in vascular invasion by recruiting osteoclasts and vessels. These findings suggest that perichondrium might serve as a stem cell reservoir and play an important role in the early development of a bone and bone marrow. PMID:12070283

  8. Synthetic quorum sensing in model microcapsule colonies

    Science.gov (United States)

    Shum, Henry; Balazs, Anna C.

    2017-08-01

    Biological quorum sensing refers to the ability of cells to gauge their population density and collectively initiate a new behavior once a critical density is reached. Designing synthetic materials systems that exhibit quorum sensing-like behavior could enable the fabrication of devices with both self-recognition and self-regulating functionality. Herein, we develop models for a colony of synthetic microcapsules that communicate by producing and releasing signaling molecules. Production of the chemicals is regulated by a biomimetic negative feedback loop, the “repressilator” network. Through theory and simulation, we show that the chemical behavior of such capsules is sensitive to both the density and number of capsules in the colony. For example, decreasing the spacing between a fixed number of capsules can trigger a transition in chemical activity from the steady, repressed state to large-amplitude oscillations in chemical production. Alternatively, for a fixed density, an increase in the number of capsules in the colony can also promote a transition into the oscillatory state. This configuration-dependent behavior of the capsule colony exemplifies quorum-sensing behavior. Using our theoretical model, we predict the transitions from the steady state to oscillatory behavior as a function of the colony size and capsule density.

  9. Trunk neural crest cells: formation, migration and beyond.

    Science.gov (United States)

    Vega-Lopez, Guillermo A; Cerrizuela, Santiago; Aybar, Manuel J

    2017-01-01

    Neural crest cells (NCCs) are a multipotent, migratory cell population that generates an astonishingly diverse array of cell types during vertebrate development. The trunk neural crest has long been considered of particular significance. First, it has been held that the trunk neural crest has a morphogenetic role, acting to coordinate the development of the peripheral nervous system, secretory cells of the endocrine system and pigment cells of the skin. Second, the trunk neural crest additionally has skeletal potential. However, it has been demonstrated that a key role of the trunk neural crest streams is to organize the innervation of the intestine. Although trunk NCCs have a limited capacity for self-renewal, sometimes they become neural-crest-derived tumor cells and reveal the fact that that NCCs and tumor cells share the same molecular machinery. In this review we describe the routes taken by trunk NCCs and consider the signals and cues that pattern these trajectories. We also discuss recent advances in the characterization of the properties of trunk NCCs for various model organisms in order to highlight common themes. Finally, looking to the future, we discuss the need to translate the wealth of data from animal studies to the clinical area in order to develop treatments for neural crest-related human diseases.

  10. The role of Rap1 in cell-cell junction formation

    NARCIS (Netherlands)

    Kooistra, M.R.H.

    2008-01-01

    Both epithelial and endothelial cells form cell-cell junctions at the cell-cell contacts to maintain tissue integrity. Proper regulation of cell-cell junctions is required for the organisation of the tissue and to prevent leakage of blood vessels. In endothelial cells, the cell-cell junctions are

  11. Mechanical Model of Geometric Cell and Topological Algorithm for Cell Dynamics from Single-Cell to Formation of Monolayered Tissues with Pattern

    KAUST Repository

    Kachalo, Sëma

    2015-05-14

    Geometric and mechanical properties of individual cells and interactions among neighboring cells are the basis of formation of tissue patterns. Understanding the complex interplay of cells is essential for gaining insight into embryogenesis, tissue development, and other emerging behavior. Here we describe a cell model and an efficient geometric algorithm for studying the dynamic process of tissue formation in 2D (e.g. epithelial tissues). Our approach improves upon previous methods by incorporating properties of individual cells as well as detailed description of the dynamic growth process, with all topological changes accounted for. Cell size, shape, and division plane orientation are modeled realistically. In addition, cell birth, cell growth, cell shrinkage, cell death, cell division, cell collision, and cell rearrangements are now fully accounted for. Different models of cell-cell interactions, such as lateral inhibition during the process of growth, can be studied in detail. Cellular pattern formation for monolayered tissues from arbitrary initial conditions, including that of a single cell, can also be studied in detail. Computational efficiency is achieved through the employment of a special data structure that ensures access to neighboring cells in constant time, without additional space requirement. We have successfully generated tissues consisting of more than 20,000 cells starting from 2 cells within 1 hour. We show that our model can be used to study embryogenesis, tissue fusion, and cell apoptosis. We give detailed study of the classical developmental process of bristle formation on the epidermis of D. melanogaster and the fundamental problem of homeostatic size control in epithelial tissues. Simulation results reveal significant roles of solubility of secreted factors in both the bristle formation and the homeostatic control of tissue size. Our method can be used to study broad problems in monolayered tissue formation. Our software is publicly

  12. Mechanical model of geometric cell and topological algorithm for cell dynamics from single-cell to formation of monolayered tissues with pattern.

    Directory of Open Access Journals (Sweden)

    Sëma Kachalo

    Full Text Available Geometric and mechanical properties of individual cells and interactions among neighboring cells are the basis of formation of tissue patterns. Understanding the complex interplay of cells is essential for gaining insight into embryogenesis, tissue development, and other emerging behavior. Here we describe a cell model and an efficient geometric algorithm for studying the dynamic process of tissue formation in 2D (e.g. epithelial tissues. Our approach improves upon previous methods by incorporating properties of individual cells as well as detailed description of the dynamic growth process, with all topological changes accounted for. Cell size, shape, and division plane orientation are modeled realistically. In addition, cell birth, cell growth, cell shrinkage, cell death, cell division, cell collision, and cell rearrangements are now fully accounted for. Different models of cell-cell interactions, such as lateral inhibition during the process of growth, can be studied in detail. Cellular pattern formation for monolayered tissues from arbitrary initial conditions, including that of a single cell, can also be studied in detail. Computational efficiency is achieved through the employment of a special data structure that ensures access to neighboring cells in constant time, without additional space requirement. We have successfully generated tissues consisting of more than 20,000 cells starting from 2 cells within 1 hour. We show that our model can be used to study embryogenesis, tissue fusion, and cell apoptosis. We give detailed study of the classical developmental process of bristle formation on the epidermis of D. melanogaster and the fundamental problem of homeostatic size control in epithelial tissues. Simulation results reveal significant roles of solubility of secreted factors in both the bristle formation and the homeostatic control of tissue size. Our method can be used to study broad problems in monolayered tissue formation. Our software

  13. Matrix elasticity of void-forming hydrogels controls transplanted-stem-cell-mediated bone formation

    Science.gov (United States)

    Huebsch, Nathaniel; Lippens, Evi; Lee, Kangwon; Mehta, Manav; Koshy, Sandeep T.; Darnell, Max C.; Desai, Rajiv M.; Madl, Christopher M.; Xu, Maria; Zhao, Xuanhe; Chaudhuri, Ovijit; Verbeke, Catia; Kim, Woo Seob; Alim, Karen; Mammoto, Akiko; Ingber, Donald E.; Duda, Georg N.; Mooney, David J.

    2015-12-01

    The effectiveness of stem cell therapies has been hampered by cell death and limited control over fate. These problems can be partially circumvented by using macroporous biomaterials that improve the survival of transplanted stem cells and provide molecular cues to direct cell phenotype. Stem cell behaviour can also be controlled in vitro by manipulating the elasticity of both porous and non-porous materials, yet translation to therapeutic processes in vivo remains elusive. Here, by developing injectable, void-forming hydrogels that decouple pore formation from elasticity, we show that mesenchymal stem cell (MSC) osteogenesis in vitro, and cell deployment in vitro and in vivo, can be controlled by modifying, respectively, the hydrogel’s elastic modulus or its chemistry. When the hydrogels were used to transplant MSCs, the hydrogel’s elasticity regulated bone regeneration, with optimal bone formation at 60 kPa. Our findings show that biophysical cues can be harnessed to direct therapeutic stem cell behaviours in situ.

  14. Dscam-Mediated Cell Recognition Regulates Neural Circuit Formation

    OpenAIRE

    Hattori, Daisuke; Millard, S. Sean; Wojtowicz, Woj M.; Zipursky, S. Lawrence

    2008-01-01

    The Dscam family of immunoglobulin cell surface proteins mediates recognition events between neurons that play an essential role in the establishment of neural circuits. The Drosophila Dscam1 locus encodes tens of thousands of cell surface proteins via alternative splicing. These isoforms exhibit exquisite isoform-specific binding in vitro that mediates homophilic repulsion in vivo. These properties provide the molecular basis for self-avoidance, an essential developmental mechanism that allo...

  15. Hypertrophic scar formation is associated with an increased number of epidermal Langerhans cells.

    NARCIS (Netherlands)

    Niessen, F.B.; Schalkwijk, J.; Vos, H.; Timens, W.

    2004-01-01

    The exact pathogenesis of hypertrophic scar and keloid formation is still unknown and a good therapy to prevent or treat these scars is lacking. Because immunological processes seem to be important in excessive scar formation, immunological cells and parameters were studied in a standardized breast

  16. Mechanisms underlying the formation of induced pluripotent stem cells

    Science.gov (United States)

    González, Federico; Huangfu, Danwei

    2015-01-01

    Human pluripotent stem cells (hPSCs) offer unique opportunities for studying human biology, modeling diseases and for therapeutic applications. The simplest approach so far to generate human PSCs lines is through reprogramming of somatic cells from an individual by defined factors, referred to simply as reprogramming. Reprogramming circumvents the ethical issues associated with human embryonic stem cells (hESCs) and nuclear transfer hESCs (nt-hESCs), and the resulting induced pluripotent stem cells (hiPSCs) retain the same basic genetic makeup as the somatic cell used for reprogramming. Since the first report of iPSCs by Takahashi and Yamanaka, the molecular mechanisms of reprogramming have been extensively investigated. A better mechanistic understanding of reprogramming is fundamental not only to iPSC biology and improving the quality of iPSCs for therapeutic use, but also to our understanding of the molecular basis of cell identity, pluripotency and plasticity. Here we summarize the genetic, epigenetic and cellular events during reprogramming, and the roles of various factors identified thus far in the reprogramming process. PMID:26383234

  17. Cell formation by myxozoan species is not explained by dogma.

    Science.gov (United States)

    Morris, David J

    2010-08-22

    Eukaryotes form new cells through the replication of nuclei followed by cytokinesis. A notable exception is reported from the class Myxosporea of the phylum Myxozoa. This assemblage of approximately 2310 species is regarded as either basal bilaterian or cnidarian, depending on the phylogenetic analysis employed. For myxosporeans, cells have long been regarded as forming within other cells by a process referred to as endogenous budding. This would involve a nucleus forming endoplasmic reticulum around it, which transforms into a new plasma membrane, thus enclosing and separating it from the surrounding cell. This remarkable process, unique within the Metazoa, is accepted as occurring within stages found in vertebrate hosts, but has only been inferred from those stages observed within invertebrate hosts. Therefore, I conducted an ultrastructural study to examine how internal cells are formed by a myxosporean parasitizing an annelid. In this case, actinospore parasite stages clearly internalized existing cells; a process with analogies to the acquisition of endosymbiotic algae by cnidarian species. A subsequent examination of the myxozoan literature did not support endogenous budding, indicating that this process, which has been a central tenet of myxozoan developmental biology for over a century, is dogma.

  18. MECHANICAL VIBRATION INHIBITS OSTEOCLAST FORMATION BY REDUCING DC-STAMP RECEPTOR EXPRESSION IN OSTEOCLAST PRECURSOR CELLS

    OpenAIRE

    Kulkarni, R.N.; Voglewede, P.A.; Liu, D.

    2013-01-01

    It is well known that physical inactivity leads to loss of muscle mass, but it also causes bone loss. Mechanistically, osteoclastogenesis and bone resorption have recently been shown to be regulated by vibration. However, the underlying mechanism behind the inhibition of osteoclast formation is yet unknown. Therefore, we investigated whether mechanical vibration of osteoclast precursor cells affects osteoclast formation by the involvement of fusion-related molecules such as dendritic cell-spe...

  19. Regulation of CCR7-dependent cell migration through?CCR7 homodimer formation

    OpenAIRE

    Kobayashi, Daichi; Endo, Masataka; Ochi, Hirotaka; Hojo, Hironobu; Miyasaka, Masayuki; Hayasaka, Haruko

    2017-01-01

    The chemokine receptor CCR7 contributes to various physiological and pathological processes including T cell maturation, T cell migration from the blood into secondary lymphoid tissues, and tumor cell metastasis to lymph nodes. Although a previous study suggested that the efficacy of CCR7 ligand-dependent T cell migration correlates with CCR7 homo- and heterodimer formation, the exact extent of contribution of the CCR7 dimerization remains unclear. Here, by inducing or disrupting CCR7 dimers,...

  20. Quantum dot-based molecular imaging of cancer cell growth using a clone formation assay.

    Science.gov (United States)

    Geng, Xia-Fei; Fang, Min; Liu, Shao-Ping; Li, Yan

    2016-10-01

    This aim of the present study was to investigate clonal growth behavior and analyze the proliferation characteristics of cancer cells. The MCF‑7 human breast cancer cell line, SW480 human colon cancer cell line and SGC7901 human gastric cancer cell line were selected to investigate the morphology of cell clones. Quantum dot‑based molecular targeted imaging techniques (which stained pan‑cytokeratin in the cytoplasm green and Ki67 in the cell nucleus yellow or red) were used to investigate the clone formation rate, cell morphology, discrete tendency, and Ki67 expression and distribution in clones. From the cell clone formation assay, the MCF‑7, SW480 and SGC7901 cells were observed to form clones on days 6, 8 and 12 of cell culture, respectively. These three types of cells had heterogeneous morphology, large nuclear:cytoplasmic ratios, and conspicuous pathological mitotic features. The cells at the clone periphery formed multiple pseudopodium. In certain clones, cancer cells at the borderline were separated from the central cell clusters or presented a discrete tendency. With quantum dot‑based molecular targeted imaging techniques, cells with strong Ki67 expression were predominantly shown to be distributed at the clone periphery, or concentrated on one side of the clones. In conclusion, cancer cell clones showed asymmetric growth behavior, and Ki67 was widely expressed in clones of these three cell lines, with strong expression around the clones, or aggregated at one side. Cell clone formation assay based on quantum dots molecular imaging offered a novel method to study the proliferative features of cancer cells, thus providing a further insight into tumor biology.

  1. Effect of granulocyte colony-stimulating factor (G-CSF) in human immunodeficiency virus-infected patients: increase in numbers of naive CD4 cells and CD34 cells makes G-CSF a candidate for use in gene therapy or to support antiretroviral therapy

    DEFF Research Database (Denmark)

    Nielsen, S D; Afzelius, P; Dam-Larsen, S

    1998-01-01

    The potential of granulocyte colony-stimulating factor (G-CSF) to mobilize CD4 cells and/or CD34 cells for use in gene therapy or to support antiretroviral therapy was examined. Ten human immunodeficiency virus-infected patients were treated with G-CSF (300 microg/day) for 5 days. Numbers of CD4....... Furthermore, the fraction of naive CD4 cells increased. These findings have implications for the design of immunotherapy or gene therapy protocols....

  2. Dynamics of vegetative cytoplasm during generative cell formation and pollen maturation in Arabidopsis thaliana

    Science.gov (United States)

    Kuang, A.; Musgrave, M. E.

    1996-01-01

    Ultrastructural changes of pollen cytoplasm during generative cell formation and pollen maturation in Arabidopsis thaliana were studied. The pollen cytoplasm develops a complicated ultrastructure and changes dramatically during these stages. Lipid droplets increase after generative cell formation and their organization and distribution change with the developmental stage. Starch grains in amyloplasts increase in number and size during generative and sperm cell formation and decrease at pollen maturity. The shape and membrane system of mitochondria change only slightly. Dictyosomes become very prominent, and numerous associated vesicles are observed during and after sperm cell formation. Endoplasmic reticulum appears extensively as stacks during sperm cell formation. Free and polyribosomes are abundant in the cytoplasm at all developmental stages although they appear denser at certain stages and in some areas. In mature pollen, all organelles are randomly distributed throughout the vegetative cytoplasm and numerous small particles appear. Organization and distribution of storage substances and appearance of these small particles during generative and sperm cell formation and pollen maturation are discussed.

  3. Formation of Cell Membrane Component Domains in Artificial Lipid Bilayer.

    Science.gov (United States)

    Tero, Ryugo; Fukumoto, Kohei; Motegi, Toshinori; Yoshida, Miyu; Niwano, Michio; Hirano-Iwata, Ayumi

    2017-12-20

    The lipid bilayer environment around membrane proteins strongly affects their structure and functions. Here, we aimed to study the fusion of proteoliposomes (PLs) derived from cultured cells with an artificial lipid bilayer membrane and the distribution of the PL components after the fusion. PLs, which were extracted as a crude membrane fraction from Chinese hamster ovary (CHO) cells, formed isolated domains in a supported lipid bilayer (SLB), comprising phosphatidylcholine (PC), phosphatidylethanolamine (PE), and cholesterol (Chol), after the fusion. Observation with a fluorescence microscope and an atomic force microscope showed that the membrane fusion occurred selectively at microdomains in the PC + PE + Chol-SLB, and that almost all the components of the PL were retained in the domain. PLs derived from human embryonic kidney 293 (HEK) cells also formed isolated domains in the PC + PE + Chol-SLB, but their fusion kinetics was different from that of the CHO-PLs. We attempted to explain the mechanism of the PL-SLB fusion and the difference between CHO- and HEK-PLs, based on a kinetic model. The domains that contained the whole cell membrane components provided environments similar to that of natural cell membranes, and were thus effective for studying membrane proteins using artificial lipid bilayer membranes.

  4. A branching process model for the analysis of abortive colony size distributions in carbon ion-irradiated normal human fibroblasts.

    Science.gov (United States)

    Sakashita, Tetsuya; Hamada, Nobuyuki; Kawaguchi, Isao; Hara, Takamitsu; Kobayashi, Yasuhiko; Saito, Kimiaki

    2014-05-01

    A single cell can form a colony, and ionizing irradiation has long been known to reduce such a cellular clonogenic potential. Analysis of abortive colonies unable to continue to grow should provide important information on the reproductive cell death (RCD) following irradiation. Our previous analysis with a branching process model showed that the RCD in normal human fibroblasts can persist over 16 generations following irradiation with low linear energy transfer (LET) γ-rays. Here we further set out to evaluate the RCD persistency in abortive colonies arising from normal human fibroblasts exposed to high-LET carbon ions (18.3 MeV/u, 108 keV/µm). We found that the abortive colony size distribution determined by biological experiments follows a linear relationship on the log-log plot, and that the Monte Carlo simulation using the RCD probability estimated from such a linear relationship well simulates the experimentally determined surviving fraction and the relative biological effectiveness (RBE). We identified the short-term phase and long-term phase for the persistent RCD following carbon-ion irradiation, which were similar to those previously identified following γ-irradiation. Taken together, our results suggest that subsequent secondary or tertiary colony formation would be invaluable for understanding the long-lasting RCD. All together, our framework for analysis with a branching process model and a colony formation assay is applicable to determination of cellular responses to low- and high-LET radiation, and suggests that the long-lasting RCD is a pivotal determinant of the surviving fraction and the RBE.

  5. A branching process model for the analysis of abortive colony size distributions in carbon ion-irradiated normal human fibroblasts

    International Nuclear Information System (INIS)

    Sakashita, Tetsuya; Kobayashi, Yasuhiko; Hamada, Nobuyuki; Kawaguchi, Isao; Hara, Takamitsu; Saito, Kimiaki

    2014-01-01

    A single cell can form a colony, and ionizing irradiation has long been known to reduce such a cellular clonogenic potential. Analysis of abortive colonies unable to continue to grow should provide important information on the reproductive cell death (RCD) following irradiation. Our previous analysis with a branching process model showed that the RCD in normal human fibroblasts can persist over 16 generations following irradiation with low linear energy transfer (LET) γ-rays. Here we further set out to evaluate the RCD persistency in abortive colonies arising from normal human fibroblasts exposed to high-LET carbon ions (18.3 MeV/u, 108 keV/μm). We found that the abortive colony size distribution determined by biological experiments follows a linear relationship on the log–log plot, and that the Monte Carlo simulation using the RCD probability estimated from such a linear relationship well simulates the experimentally determined surviving fraction and the relative biological effectiveness (RBE). We identified the short-term phase and long-term phase for the persistent RCD following carbon-ion irradiation, which were similar to those previously identified following γ-irradiation. Taken together, our results suggest that subsequent secondary or tertiary colony formation would be invaluable for understanding the long-lasting RCD. All together, our framework for analysis with a branching process model and a colony formation assay is applicable to determination of cellular responses to low- and high-LET radiation, and suggests that the long-lasting RCD is a pivotal determinant of the surviving fraction and the RBE. (author)

  6. Investigation of Contact Formation during Silicon Solar Cell Production

    Science.gov (United States)

    Mojrová, Barbora

    2016-05-01

    This article deals with the investigation of the influence of sintering conditions on the formation process of screen printed contacts on passivated boron doped P+ emitters. The experiment was focused on measuring of resistance changes of two thick film pastes during firing processes with different conditions. Two different temperature profiles were compared at an atmospheric concentration of O2. The influence of the O2 concentration on resistance was investigated for one profile. A rapid thermal processing furnace modified for in-situ resistance measurements was used. The change of resistance was measured simultaneously with the temperature.

  7. Rap1 integrates tissue polarity, lumen formation, and tumorigenicpotential in human breast epithelial cells

    Energy Technology Data Exchange (ETDEWEB)

    Itoh, Masahiko; Nelson, Celeste M.; Myers, Connie A.; Bissell,Mina J.

    2006-09-29

    Maintenance of apico-basal polarity in normal breast epithelial acini requires a balance between cell proliferation, cell death, and proper cell-cell and cell-extracellular matrix signaling. Aberrations in any of these processes can disrupt tissue architecture and initiate tumor formation. Here we show that the small GTPase Rap1 is a crucial element in organizing acinar structure and inducing lumen formation. Rap1 activity in malignant HMT-3522 T4-2 cells is appreciably higher than in S1 cells, their non-malignant counterparts. Expression of dominant-negative Rap1 resulted in phenotypic reversion of T4-2 cells, led to formation of acinar structures with correct apico-basal polarity, and dramatically reduced tumor incidence despite the persistence of genomic abnormalities. The resulting acini contained prominent central lumina not observed when other reverting agents were used. Conversely, expression of dominant-active Rap1 in T4-2 cells inhibited phenotypic reversion and led to increased invasiveness and tumorigenicity. Thus, Rap1 acts as a central regulator of breast architecture, with normal levels of activation instructing apical polarity during acinar morphogenesis, and increased activation inducing tumor formation and progression to malignancy.

  8. Singlet oxygen-mediated formation of protein peroxides within cells

    International Nuclear Information System (INIS)

    Wright, A.; Policarpio, V.

    2003-01-01

    Full text: Singlet oxygen is generated by a number of cellular, enzymatic and chemical reactions as well as by exposure to UV, or visible light in the presence of a sensitizer; as a consequence this oxidant has been proposed as a damaging agent in a number of pathologies including photo-aging and skin cancer. Proteins are major targets for singlet oxygen as a result of their abundance and high rate constants for reaction. In this study it is shown that illumination of viable, sensitizer-loaded, THP-1 (human monocyte-like) cells with visible light gives rise to intra-cellular protein-derived peroxides. The peroxide yield increases with illumination time, requires the presence of the sensitizer, is enhanced in D 2 O, and decreased by azide; these data are consistent with the mediation of singlet oxygen. The concentration of peroxides detected, which is not affected by glucose or ascorbate loading of the cells, corresponds to ca. 1.5 nmoles peroxide per 10 6 cells using rose bengal as sensitizer, or 10 nmoles per mg cell protein and account for up to ca. 15% of the O 2 consumed by the cells. Similar peroxides have been detected on isolated cellular proteins exposed to light in the presence of rose bengal and oxygen. After cessation of illumination, the cellular protein peroxide levels decreases with t 1/2 ca. 4 hrs at 37 deg C, and this is associated with increased cell lysis. Decomposition of protein peroxides formed within cells, or on isolated cellular proteins, by metal ions, gives rise to radicals as detected by EPR spin trapping. These protein peroxides, and radicals derived from them, can inactivate key cellular enzymes (including caspases, GAPDH and glutathione reductase) and induce DNA base oxidation, strand breaks and DNA-protein cross-links. These studies demonstrate that exposure of intact cells to visible light in the presence of a sensitizer gives rise to novel long-lived, but reactive, intra-cellular protein peroxides via singlet oxygen

  9. Co-administration of plasmid-encoded granulocyte-macrophage colony-stimulating factor increases human immunodeficiency virus-1 DNA vaccine-induced polyfunctional CD4+ T-cell responses.

    Science.gov (United States)

    Santana, Vinicius Canato; Almeida, Rafael Ribeiro; Ribeiro, Susan Pereira; Ferreira, Luís Carlos de Souza; Kalil, Jorge; Rosa, Daniela Santoro; Cunha-Neto, Edecio

    2015-12-01

    T-cell based vaccines against human immunodeficiency virus (HIV) generate specific responses that may limit both transmission and disease progression by controlling viral load. Broad, polyfunctional, and cytotoxic CD4+T-cell responses have been associated with control of simian immunodeficiency virus/HIV-1 replication, supporting the inclusion of CD4+ T-cell epitopes in vaccine formulations. Plasmid-encoded granulocyte-macrophage colony-stimulating factor (pGM-CSF) co-administration has been shown to induce potent CD4+ T-cell responses and to promote accelerated priming and increased migration of antigen-specific CD4+ T-cells. However, no study has shown whether co-immunisation with pGM-CSF enhances the number of vaccine-induced polyfunctional CD4+ T-cells. Our group has previously developed a DNA vaccine encoding conserved, multiple human leukocyte antigen (HLA)-DR binding HIV-1 subtype B peptides, which elicited broad, polyfunctional and long-lived CD4+ T-cell responses. Here, we show that pGM-CSF co-immunisation improved both magnitude and quality of vaccine-induced T-cell responses, particularly by increasing proliferating CD4+ T-cells that produce simultaneously interferon-γ, tumour necrosis factor-α and interleukin-2. Thus, we believe that the use of pGM-CSF may be helpful for vaccine strategies focused on the activation of anti-HIV CD4+ T-cell immunity.

  10. Effect of mobilization of bone marrow stem cells by granulocyte colony stimulating factor on clinical symptoms, left ventricular perfusion and function in patients with severe chronic ischemic heart disease

    DEFF Research Database (Denmark)

    Wang, Yongzhong; Tägil, Kristina; Ripa, Rasmus S.

    2005-01-01

    OBJECTIVES: A phase I safety and efficacy study with granulocyte colony stimulating factor (G-CSF) mobilization of bone marrow stem cells to induce vasculogenesis in patients with severe ischemic heart disease (IHD) was conducted. DESIGN, PATIENTS AND RESULTS: 29 patients with IHD participated...... in 'mobilizers'. At the follow-up, G-CSF treated had improved in CCS classification, NTG consumption and angina attacks, but the controls only in CCS classification. No difference was seen between the two groups. The decline in NTG consumption tended to be significant in 'mobilizers' compared to controls...

  11. Proliferation-stimulating effect of colony stimulating factor 2 on porcine trophectoderm cells is mediated by activation of phosphatidylinositol 3-kinase and extracellular signal-regulated kinase 1/2 mitogen-activated protein kinase.

    Directory of Open Access Journals (Sweden)

    Wooyoung Jeong

    Full Text Available Colony-stimulating factor 2 (CSF2, also known as granulocyte macrophage colony-stimulating factor, facilitates mammalian embryonic development and implantation. However, biological functions and regulatory mechanisms of action of porcine endometrial CSF2 in peri-implantation events have not been elucidated. The aim of present study was to determine changes in cellular activities induced by CSFs and to access CSF2-induced intracellular signaling in porcine primary trophectoderm (pTr cells. Differences in expression of CSF2 mRNA in endometrium from cyclic and pregnant gilts were evaluated. Endometrial CSF2 mRNA expression increases during the peri-implantation period, Days 10 to 14 of pregnancy, as compared to the estrous cycle. pTr cells obtained in Day 12 of pregnancy were cultured in the presence or absence of CSF2 (20 ng/ml and LY294002 (20 µM, U0126 (20 µM, rapamycin (20 nM, and SB203580 (20 µM. CSF2 in pTr cell culture medium at 20 ng/ml significantly induced phosphorylation of AKT1, ERK1/2, MTOR, p70RSK and RPS6 protein, but not STAT3 protein. Also, the PI3K specific inhibitor (LY294002 abolished CSF2-induced increases in p-ERK1/2 and p-MTOR proteins, as well as CSF2-induced phosphorylation of AKT1. Changes in proliferation and migration of pTr cells in response to CSF2 were examined in dose- and time-response experiments. CSF2 significantly stimulated pTr cell proliferation and, U0126, rapamycin and LY294002 blocked this CSF2-induced proliferation of pTr cells. Collectively, during the peri-implantation phase of pregnancy in pigs, endometrial CSF2 stimulates proliferation of trophectoderm cells by activation of the PI3K-and ERK1/2 MAPK-dependent MTOR signal transduction cascades.

  12. Mobilization of regulatory T cells in response to carotid injury does not influence subsequent neointima formation.

    Directory of Open Access Journals (Sweden)

    Amit Saxena

    Full Text Available AIM: T cells have been attributed an important role in modulating repair responses following vascular injury. The aim of this study was to investigate the role of different T cell subsets in this context. METHODS AND RESULTS: A non-obstructive collar was introduced to inflict carotid artery injury in mice and subsequent activation of immune cells in draining lymph nodes and spleen were studied by flow cytometry. Carotid artery injury of wild type mice was associated with mobilization of both Th1 type CD4(+IFNγ(+ and regulatory CD4(+CD25(+FoxP3(+ T cells in draining lymph nodes. Studies using FoxP3-green fluorescent protein (GFP transgenic C57/Bl6 mice demonstrated scattered presence of regulatory T cells in the adventitial tissue of injured arteries as well as a massive emigration of regulatory T cells from the spleen in response to carotid injury. However, deletion of antigen presentation to CD4+ T cells (H2(0 mice, as well as deletion of regulatory T cells (through treatment with blocking anti-CD25 antibodies, did not affect neointima formation. Also deletion of antigen presentation to CD8(+ T cells (Tap1(0 mice was without effect on carotid collar-induced neointima formation. CONCLUSION: The results demonstrate that carotid artery injury is associated with mobilization of regulatory T cells. Depletion of regulatory T cells does not, however, influence the subsequent repair processes leading to the formation of a neointima. The results also demonstrate that lack of CD8(+ T cells does not influence neointima formation in presence of functional CD4(+ T cells and B cells.

  13. Growth-mediated autochemotactic pattern formation in self-propelling bacteria

    Science.gov (United States)

    Mukherjee, Mrinmoy; Ghosh, Pushpita

    2018-01-01

    Bacteria, while developing a multicellular colony or biofilm, can undergo pattern formation by diverse intricate mechanisms. One such route is directional movement or chemotaxis toward or away from self-secreted or externally employed chemicals. In some bacteria, the self-produced signaling chemicals or autoinducers themselves act as chemoattractants or chemorepellents and thereby regulate the directional movements of the cells in the colony. In addition, bacteria follow a certain growth kinetics which is integrated in the process of colony development. Here, we study the interplay of bacterial growth dynamics, cell motility, and autochemotactic motion with respect to the self-secreted diffusive signaling chemicals in spatial pattern formation. Using a continuum model of motile bacteria, we show growth can act as a crucial tuning parameter in determining the spatiotemporal dynamics of a colony. In action of growth dynamics, while chemoattraction toward autoinducers creates arrested phase separation, pattern transitions and suppression can occur for a fixed chemorepulsive strength.

  14. Effect of Emdogain enamel matrix derivative and BMP-2 on the gene expression and mineralized nodule formation of alveolar bone proper-derived stem/progenitor cells.

    Science.gov (United States)

    Fawzy El-Sayed, Karim M; Dörfer, Christof; Ungefroren, Hendrick; Kassem, Neemat; Wiltfang, Jörg; Paris, Sebastian

    2014-07-01

    The objective of this study was to evaluate the effect of Emdogain (Enamel Matrix Derivative, EMD) and Bone Morphogenetic Protein-2 (BMP-2), either solely or in combination, on the gene expression and mineralized nodule formation of alveolar bone proper-derived stem/progenitor cells. Stem/progenitor cells were isolated from human alveolar bone proper, magnetically sorted using STRO-1 antibodies, characterized flowcytometrically for their surface markers' expression, and examined for colony formation and multilineage differentiation potential. Subsequently, cells were treated over three weeks with 100 μg/ml Emdogain (EMD-Group), or 100 ng/ml BMP-2 (BMP-Group), or a combination of 100 ng/ml BMP-2 and 100 μg/ml Emdogain (BMP/EMD-Group). Unstimulated stem/progenitor cells (MACS(+)-Group) and osteoblasts (OB-Group) served as controls. Osteogenic gene expression was analyzed using RTq-PCR after 1, 2 and 3 weeks (N = 3/group). Mineralized nodule formation was evaluated by Alizarin-Red staining. BMP and EMD up-regulated the osteogenic gene expression. The BMP Group showed significantly higher expression of Collagen-I, III, and V, Alkaline phosphatase and Osteonectin compared to MACS(+)- and OB-Group (p Emdogain and BMP-2 up-regulate the osteogenic gene expression of stem/progenitor cells. The combination of BMP-2 and Emdogain showed no additive effect and would not be recommended for a combined clinical stimulation. Copyright © 2013 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

  15. Chinese herb derived-Rocaglamide A is a potent inhibitor of pancreatic cancer cells

    OpenAIRE

    Wang, Baochun; Li, Yixiong; Tan, Fengbo; Xiao, Zhanxiang

    2016-01-01

    Pancreatic cancer ranks No.1 in mortality rate worldwide. This study aims to identify the novel anti-pancreatic cancer drugs. Human pancreatic carcinoma cell lines were purchased from ATCC. CPE-based screening assay was used to examine the cell viability. Patient derived tumor xenografts in SCID mice was established. The Caspase-3 and 7 activities were measured using the Caspase Glo 3/7 Assay kit. Soft agar colony formation assay was used to evaluate the colony formation. Wound healing assay ...

  16. LncRNA TUG1 influences papillary thyroid cancer cell proliferation, migration and EMT formation through targeting miR-145.

    Science.gov (United States)

    Lei, Hongwei; Gao, Yan; Xu, Xiaoying

    2017-07-01

    LncRNA TUG1, a tumor oncogene associated with various human cancers, has been reported to be involved in regulating various cellular processes, such as proliferation, apoptosis and invasion through targeting multiple genes. However, its biological function in thyroid cancer cells has not been elucidated. The aim of this study is to measure TUG1 expression level and evaluate its function in thyroid cancer cells. LncRNA TUG1 expression levels in thyroid cancer tissues and three thyroid cancer cell lines (the ATC cell lines SW1736 and KAT18 and the FTC cell line FTC133) were assessed by qRT-PCR and compared with that of the human normal breast epithelial cell HGC-27. MTT assay, colony formation assay, transwell assay and western blot analysis were performed to assess the effects of TUG1 on proliferation, metastasis and EMT formation in thyroid cancer cells in vitro. Rescue assay was performed to further confirm that TUG1 contributes to the progression of thyroid cancer cells through regulating miR-145/ZEB1 signal pathway. LncRNA TUG1 was found to be up-regulated in thyroid cancer tissues and thyroid cancer cells compared with that in the human normal breast epithelial cell HGC-27. Increased lncRNA TUG1 expression was found to significantly promote tumor cell proliferation, and facilitate cell invasion, while down-regulated TUG1 could obviously inhibit cell proliferation, migration/invasion and reverse EMT to MET. These results indicated that TUG1 may contribute to the progression of thyroid cancer cells by function as a ceRNA competitive sponging miR-145, and that lncRNA TUG1 is associated with tumor progression in thyroid cancer cells. © The Author 2017. Published by Oxford University Press on behalf of the Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  17. Food and Coloniality

    Directory of Open Access Journals (Sweden)

    Adolfo Albán Achinte

    2011-05-01

    Full Text Available The author tackles the alimentary dimension of life, as something that goes beyond the simple act of ingesting food to acquire nutrients, to concentrate on the cultural implications of eating. To eat is more than to feed oneself, for eating is never by itself a wholly innocent act; that is, eating is never completely stripped from the social relationships of those gathered around a table.From this perspective, the article examines coloniality in all its forms (of power, of knowledge and of being, and shows their function as mechanisms of both alimentary enunciation and classification, that are responsible of the gastronomic supplantation of produce and food from the New World with the goods and customs that were so dear to European settlers (not forgetting that the influx of products and seasonings went also in the other direction. The colonizing project included thus, besides its religious, political and administrative pretenses, a gastronomical element, to be found in the eagerness of the colonizers to reproduce the alimentary imprint of their homeland in the new found territories, at least as far as the circumstances and the climate allowed it. Among all the facets the production of knowledge can acquire, gastronomy has been poorly studied —not to say completely silenced— in its role as a token of cultural divides, in which a coloniality of flavors and palates has been carried out.

  18. Analysis of Colonial Currency

    Science.gov (United States)

    Kurkowski, Michael; Cangany, Catherine; Jordan, Louis; Manukyan, Khachatur; Schultz, Zachary; Wiescher, Michael

    2017-09-01

    This project entailed studying the cellulose in paper, the ink, colorants, and other materials used to produce American colonial currency. The technique primarily used in this project was X-Ray Fluorescence Spectroscopy (XRF). XRF mapping was used to provide both elemental analysis of large-scale objects as well as microscopic examination of individual pigment particles in ink, in addition to the inorganic additives used to prepare paper. The combination of elemental mapping with Fourier Transform Infrared (FTIR) and Raman Spectroscopies permits an efficient analysis of the currency. These spectroscopic methods help identify the molecular composition of the pigments. This combination of atomic and molecular analytical techniques provided an in-depth characterization of the paper currency on the macro, micro, and molecular levels. We have identified several of pigments that were used in the preparation of inks and colorants. Also, different inorganic crystals, such as alumina-silicates, have been detected in different papers. The FTIR spectroscopy allowed us to determine the type of cellulose fiber used in the production of paper currency. Our future research will be directed toward revealing important historical relationships between currencies printed throughout the colonies. ISLA Da Vinci Grant.

  19. Arabidopsis R-SNARE proteins VAMP721 and VAMP722 are required for cell plate formation.

    Directory of Open Access Journals (Sweden)

    Liang Zhang

    Full Text Available BACKGROUND: Cell plate formation during plant cytokinesis is facilitated by SNARE complex-mediated vesicle fusion at the cell-division plane. However, our knowledge regarding R-SNARE components of membrane fusion machinery for cell plate formation remains quite limited. METHODOLOGY/PRINCIPAL FINDINGS: We report the in vivo function of Arabidopsis VAMP721 and VAMP722, two closely sequence-related R-SNAREs, in cell plate formation. Double homozygous vamp721vamp722 mutant seedlings showed lethal dwarf phenotypes and were characterized by rudimentary roots, cotyledons and hypocotyls. Furthermore, cell wall stubs and incomplete cytokinesis were frequently observed in vamp721vamp722 seedlings. Confocal images revealed that green fluorescent protein-tagged VAMP721 and VAMP722 were preferentially localized to the expanding cell plates in dividing cells. Drug treatments and co-localization analyses demonstrated that punctuate organelles labeled with VAMP721 and VAMP722 represented early endosomes overlapped with VHA-a1-labeled TGN, which were distinct from Golgi stacks and prevacuolar compartments. In addition, protein traffic to the plasma membrane, but not to the vacuole, was severely disrupted in vamp721vamp722 seedlings by subcellular localization of marker proteins. CONCLUSION/SIGNIFICANCE: These observations suggest that VAMP721 and VAMP722 are involved in secretory trafficking to the plasma membrane via TGN/early endosomal compartment, which contributes substantially to cell plate formation during plant cytokinesis.

  20. Complement Activation Induces Neutrophil Adhesion and Neutrophil-Platelet Aggregate Formation on Vascular Endothelial Cells

    Directory of Open Access Journals (Sweden)

    Magdalena Riedl

    2017-01-01

    Discussion: Therefore, our findings of (i neutrophils adhering to complement-activated endothelial cells, (ii the formation of neutrophil-platelet aggregates on endothelial cells, and (iii the ability of aHUS serum to induce similar effects identify a possible role for neutrophils in aHUS manifestation.

  1. Hard tissue formation of STRO-1-selected rat dental pulp stem cells in vivo.

    NARCIS (Netherlands)

    Yang, X.; Walboomers, X.F.; Beucken, J.J.J.P van den; Bian, Z.; Fan, M.; Jansen, J.A.

    2009-01-01

    The objective of this study was to examine hard tissue formation of STRO-1-selected rat dental pulp-derived stem cells, seeded into a calcium phosphate ceramic scaffold, and implanted subcutaneously in mice. Previously, STRO-1 selection was used to obtain a mesenchymal stem cell progenitor

  2. De novo formation of centrosomes in vertebrate cells arrested during S phase

    NARCIS (Netherlands)

    Khodjakov, A; Rieder, CL; Sluder, G; Cassels, G; Sibon, O; Wang, CL

    2002-01-01

    The centrosome usually replicates in a semiconservative fashion, i.e., new centrioles form in association with preexisting "maternal" centrioles. De novo formation of centrioles has been reported for a few highly specialized cell types but it has not been seen in vertebrate somatic cells. We find

  3. BCL6 interacting corepressor contributes to germinal center T follicular helper cell formation and B cell helper function

    OpenAIRE

    Yang, Jessica A.; Tubo, Noah J.; Gearhart, Micah D.; Bardwell, Vivian J.; Jenkins, Marc K.

    2015-01-01

    CD4+ germinal center (GC) T follicular helper (GC-Tfh) cells help B cells become long-lived plasma cells and memory cells. The transcriptional repressor BCL6 plays a key role in GC-Tfh formation by inhibiting the expression of genes that promote differentiation into other lineages. We determined whether BCOR, a component of a Polycomb repressive complex that interacts with the BCL6 BTB domain, influences GC-Tfh differentiation. T cell-targeted BCOR deficiency led to a substantial loss of pept...

  4. Formation of large coronary arteries by cardiac progenitor cells

    Science.gov (United States)

    Tillmanns, Jochen; Rota, Marcello; Hosoda, Toru; Misao, Yu; Esposito, Grazia; Gonzalez, Arantxa; Vitale, Serena; Parolin, Carola; Yasuzawa-Amano, Saori; Muraski, John; De Angelis, Antonella; LeCapitaine, Nicole; Siggins, Robert W.; Loredo, Maria; Bearzi, Claudia; Bolli, Roberto; Urbanek, Konrad; Leri, Annarosa; Kajstura, Jan; Anversa, Piero

    2008-01-01

    Coronary artery disease is the most common cause of cardiac failure in the Western world, and to date there is no alternative to bypass surgery for severe coronary atherosclerosis. We report that c-kit-positive cardiac progenitor cells (CPCs) activated with insulin-like growth factor 1 and hepatocyte growth factor before their injection in proximity of the site of occlusion of the left coronary artery in rats, engrafted within the host myocardium forming temporary niches. Subsequently, CPCs divided and differentiated into endothelial cells and smooth muscle cells and, to a lesser extent, into cardiomyocytes. The acquisition of vascular lineages appeared to be mediated by the up-regulation of hypoxia-inducible factor 1α, which promoted the synthesis and secretion of stromal-derived factor 1 from hypoxic coronary vessels. Stromal-derived factor 1 was critical in the conversion of CPCs to the vascular fate. CPCs formed conductive and intermediate-sized coronary arteries together with resistance arterioles and capillaries. The new vessels were connected with the primary coronary circulation, and this increase in vascularization more than doubled myocardial blood flow in the infarcted myocardium. This beneficial effect, together with myocardial regeneration attenuated postinfarction dilated myopathy, reduced infarct size and improved function. In conclusion, locally delivered activated CPCs generate de novo coronary vasculature and may be implemented clinically for restoration of blood supply to the ischemic myocardium. PMID:18216245

  5. Mxi1 influences cyst formation in three-dimensional cell culture

    Directory of Open Access Journals (Sweden)

    Yeon Joo Yook

    2012-03-01

    Full Text Available Cyst formation is a major characteristic of ADPKD and iscaused by the abnormal proliferation of epithelial cells. Renalcyst formation disrupts renal function and induces diversecomplications. The mechanism of cyst formation is unclear.mIMCD-3 cells were established to develop simple epithelialcell cysts in 3-D culture. We confirmed previously that Mxi1plays a role in cyst formation in Mxi1-deficient mice. Cysts inMxi1 transfectanted cells were showed by collagen or mebiolgels in 3-D cell culture system. Causative genes of ADPKDwere measured by q RT-PCR. Herein, Mxi1 transfectants rarelyformed a simple epithelial cyst and induced cell death.Overexpression of Mxi1 resulted in a decrease in the PKD1,PKD2 and c-myc mRNA relating to the pathway of cystformation. These data indicate that Mxi1 influences cystformation of mIMCD-3 cells in 3-D culture and that Mxi1 maycontrol the mechanism of renal cyst formation. [BMB reports2012; 45(3: 189-193

  6. αII-spectrin in T cells is involved in the regulation of cell-cell contact leading to immunological synapse formation?

    Directory of Open Access Journals (Sweden)

    Justyna M Meissner

    Full Text Available T-lymphocyte activation after antigen presentation to the T-Cell Receptor (TCR is a critical step in the development of proper immune responses to infection and inflammation. This dynamic process involves reorganization of the actin cytoskeleton and signaling molecules at the cell membrane, leading to the formation of the Immunological Synapse (IS. The mechanisms regulating the formation of the IS are not completely understood. Nonerythroid spectrin is a membrane skeletal protein involved in the regulation of many cellular processes, including cell adhesion, signaling and actin cytoskeleton remodeling. However, the role of spectrin in IS formation has not been explored. We used molecular, imaging and cellular approaches to show that nonerythroid αII-spectrin redistributes to the IS during T-cell activation. The redistribution of spectrin coincides with the relocation of CD45 and LFA-1, two components essential for IS formation and stability. We assessed the role of spectrin by shRNA-mediated depletion from Jurkat T cells and show that spectrin-depleted cells exhibit decreased adhesion and are defective in forming lamellipodia and filopodia. Importantly, IS formation is impaired in spectrin-depleted cells. Thus, spectrin may be engaged in regulation of distinct events necessary for the establishment and maturity of the IS: besides the involvement of spectrin in the control of CD45 and LFA-1 surface display, spectrin acts in the establishment of cell-cell contact and adhesion processes during the formation of the IS.

  7. Centriole triplet microtubules are required for stable centriole formation and inheritance in human cells.

    Science.gov (United States)

    Wang, Jennifer T; Kong, Dong; Hoerner, Christian R; Loncarek, Jadranka; Stearns, Tim

    2017-09-14

    Centrioles are composed of long-lived microtubules arranged in nine triplets. However, the contribution of triplet microtubules to mammalian centriole formation and stability is unknown. Little is known of the mechanism of triplet microtubule formation, but experiments in unicellular eukaryotes indicate that delta-tubulin and epsilon-tubulin, two less-studied tubulin family members, are required. Here, we report that centrioles in delta-tubulin and epsilon-tubulin null mutant human cells lack triplet microtubules and fail to undergo centriole maturation. These aberrant centrioles are formed de novo each cell cycle, but are unstable and do not persist to the next cell cycle, leading to a futile cycle of centriole formation and disintegration. Disintegration can be suppressed by paclitaxel treatment. Delta-tubulin and epsilon-tubulin physically interact, indicating that these tubulins act together to maintain triplet microtubules and that these are necessary for inheritance of centrioles from one cell cycle to the next.

  8. Statistical analysis of clone formation in cultures of human stem cells.

    Science.gov (United States)

    Bochkov, N P; Vinogradova, M S; Volkov, I K; Voronina, E S; Kuleshov, N P

    2011-08-01

    We performed a statistical analysis of clone formation from aneuploid cells (chromosomes 6, 8, 11, X) in cultures of bone marrow-derived human multipotent mesenchymal stromal cells by spontaneous level of aneuploidy at different terms of culturing (from 2 to 19 cell cycles). It was found that the duration of cell cycle increased from 65.6 h at passages 2-3 to 164.5 h at passage 12. The expected ratio of aneuploid cells was calculated using modeled 5, 10, 20 and 30% selective preference in reproduction. The size of samples for detecting 10, 25, and 50% increased level of aneuploidy was calculated. The presented principles for evaluation of aneuploid clone formation may be used to distinguish clones of any abnormal cells.

  9. Cancer cells increase endothelial cell tube formation and survival by activating the PI3K/Akt signalling pathway.

    Science.gov (United States)

    Cheng, Hao-Wei; Chen, Yi-Fang; Wong, Jau-Min; Weng, Chia-Wei; Chen, Hsuan-Yu; Yu, Sung-Liang; Chen, Huei-Wen; Yuan, Ang; Chen, Jeremy J W

    2017-02-07

    Angiogenesis is a hallmark of cancer and plays a critical role in lung cancer progression, which involves interactions between cancer cells, endothelial cells and the surrounding microenvironment. However, the gene expression profiles and the changes in the biological phenotype of vascular endothelial cells after interactions with lung cancer cells remain unclear. An indirect transwell co-culture system was used to survey the interaction between human umbilical vein endothelial cells (HUVECs) and human lung adenocarcinoma CL1-5 cells, as well as to investigate the morphological and molecular changes of HUVECs. The differentially expressed genes (DEGs) in HUVECs after co-culture with cancer cells were identified by microarray. Moreover, a publicly available microarray dataset of 293 non-small-cell lung cancer (NSCLC) patients was employed to evaluate the prognostic power of the gene signatures derived from HUVECs. The interaction between HUVECs and lung cancer cells changes the morphology of HUVECs, causing them to have a mesenchymal-like morphology and alter their cytoskeleton organization. Furthermore, after co-culture with lung cancer cells, HUVECs showed increased cell motility and microvessel tube formation ability and a decreased apoptotic percentage. Transcriptomic profiling of HUVECs revealed that many survival-, apoptosis- and angiogenesis-related genes were differentially expressed after interactions with lung cancer cells. Further investigations showed that the PI3K/Akt signalling pathway and COX-2 are involved in endothelial tube formation under the stimulation of lung cancer cells. Moreover, Rac-1 activation might promote endothelial cell motility through the increased formation of lamellipodia and filopodia. The inhibitors of PI3K and COX-2 could reverse the increased tube formation and induce the apoptosis of HUVECs. In addition, the gene signatures derived from the DEGs in HUVECs could predict overall survival and disease-free survival in NSCLC

  10. Putrescine controls the formation of Escherichia coli persister cells tolerant to aminoglycoside netilmicin.

    Science.gov (United States)

    Tkachenko, Alexander G; Kashevarova, Natalya M; Karavaeva, Elena A; Shumkov, Mikhail S

    2014-12-01

    Persisters are suggested to be the products of a phenotypic variability that are quasi-dormant forms of regular bacterial cells highly tolerant to antibiotics. Our previous investigations revealed that a decrease in antibiotic tolerance of Escherichia coli cells could be reached through the inhibition of key enzymes of polyamine synthesis (putrescine, spermidine). We therefore assumed that polyamines could be involved in persister cell formation. Data obtained in our experiments with the polyamine-deficient E. coli strain demonstrate that the formation of persisters tolerant to netilmicin is highly upregulated by putrescine in a concentration-dependent manner when cells enter the stationary phase. This period is also accompanied by dissociation of initially homogenous subpopulation of persister cells to some fractions differing in their levels of tolerance to netilmicin. With three independent experimental approaches, we demonstrate that putrescine-dependent upregulation of persister cell formation is mediated by stimulation of rpoS expression. Complementary activity of putrescine and RpoS results in ~ 1000-fold positive effect on persister cell formation. © 2014 Federation of European Microbiological Societies.

  11. The role of Ca2+ influx in endocytic vacuole formation in pancreatic acinar cells

    Science.gov (United States)

    Voronina, Svetlana; Collier, David; Chvanov, Michael; Middlehurst, Ben; Beckett, Alison J.; Prior, Ian A.; Criddle, David N.; Begg, Malcolm; Mikoshiba, Katsuhiko; Sutton, Robert; Tepikin, Alexei V.

    2014-01-01

    The inducers of acute pancreatitis trigger a prolonged increase in the cytosolic Ca2+ concentration ([Ca2+]c), which is responsible for the damage to and eventual death of pancreatic acinar cells. Vacuolization is an important indicator of pancreatic acinar cell damage. Furthermore, activation of trypsinogen occurs in the endocytic vacuoles; therefore the vacuoles can be considered as ‘initiating’ organelles in the development of the cell injury. In the present study, we investigated the relationship between the formation of endocytic vacuoles and Ca2+ influx developed in response to the inducers of acute pancreatitis [bile acid taurolithocholic acid 3-sulfate (TLC-S) and supramaximal concentration of cholecystokinin-8 (CCK)]. We found that the inhibitor of STIM (stromal interaction molecule)/Orai channels, GSK-7975A, effectively suppressed both the Ca2+ influx (stimulated by inducers of pancreatitis) and the formation of endocytic vacuoles. Cell death induced by TLC-S or CCK was also inhibited by GSK-7975A. We documented the formation of endocytic vacuoles in response to store-operated Ca2+ entry (SOCE) induced by thapsigargin [TG; inhibitor of sarcoplasmic/endoplasmic reticulum (ER) Ca2+ pumps] and observed strong inhibition of TG-induced vacuole formation by GSK-7975A. Finally, we found that structurally-unrelated inhibitors of calpain suppress formation of endocytic vacuoles, suggesting that this Ca2+-dependent protease is a mediator between Ca2+ elevation and endocytic vacuole formation. PMID:25370603

  12. Thermal characterizations of a large-format lithium ion cell focused on high current discharges

    Science.gov (United States)

    Veth, C.; Dragicevic, D.; Merten, C.

    2014-12-01

    The thermal behavior of a large-format lithium ion cell has been investigated during measurements on cell and battery level. High current discharges up to 300 A are the main topic of this study. This paper demonstrates that the temperature response to high current loads provides the possibility to investigate internal cell parameters and their inhomogeneity. In order to identify thermal response caused by internal cell processes, the heat input due to contact resistances has been minimized. The differences between the thermal footprint of a cell during cell and battery measurements are being addressed. The study presented here focuses on the investigation of thermal hot and cold spots as well as temperature gradients in a 50 Ah pouch cell. Furthermore, it is demonstrated that the difference between charge and discharge can have significant influence on the thermal behavior of lithium ion cells. Moreover, the miscellaneous thermal characteristics of differently aged lithium ion cells highlight the possibility of an ex-situ non-destructive post-mortem-analysis, providing the possibility of a qualitative and quantitative characterization of inhomogeneous cell-aging. These investigations also generate excellent data for the validation and parameterization of electro-thermal cell models, predicting the distribution of temperature, current, potential, SOC and SOH inside large-format cells.

  13. The MP65 gene is required for cell wall integrity, adherence to epithelial cells and biofilm formation in Candida albicans

    Directory of Open Access Journals (Sweden)

    Girolamo Antonietta

    2011-05-01

    Full Text Available Abstract Background The MP65 gene of Candida albicans (orf19.1779 encodes a putative β-glucanase mannoprotein of 65 kDa, which plays a main role in a host-fungus relationship, morphogenesis and pathogenicity. In this study, we performed an extensive analysis of a mp65Δ mutant to assess the role of this protein in cell wall integrity, adherence to epithelial cells and biofilm formation. Results The mp65Δ mutant showed a high sensitivity to a range of cell wall-perturbing and degrading agents, especially Congo red, which induced morphological changes such as swelling, clumping and formation of hyphae. The mp65Δ mutant showed an activation of two MAPKs (Mkc1p and Cek1p, a high level of expression of two stress-related genes (DDR48 and SOD5, and a modulated expression of β-glucan epitopes, but no gross changes in cell wall polysaccharide composition. Interestingly, the mp65Δ mutant displayed a marked reduction in adhesion to BEC and Caco-2 cells and severe defects in biofilm formation when compared to the wild type. All of the mentioned properties were totally or partially recovered in a revertant strain, demonstrating the specificity of gene deletion. Conclusions We demonstrate that the MP65 gene of Candida albicans plays a significant role in maintaining cell wall integrity, as well as in adherence to epithelia and biofilm formation, which are major virulence attributes of this fungus.

  14. Collective motion of cells mediates segregation and pattern formation in co-cultures.

    Directory of Open Access Journals (Sweden)

    Elod Méhes

    Full Text Available Pattern formation by segregation of cell types is an important process during embryonic development. We show that an experimentally yet unexplored mechanism based on collective motility of segregating cells enhances the effects of known pattern formation mechanisms such as differential adhesion, mechanochemical interactions or cell migration directed by morphogens. To study in vitro cell segregation we use time-lapse videomicroscopy and quantitative analysis of the main features of the motion of individual cells or groups. Our observations have been extensive, typically involving the investigation of the development of patterns containing up to 200,000 cells. By either comparing keratocyte types with different collective motility characteristics or increasing cells' directional persistence by the inhibition of Rac1 GTP-ase we demonstrate that enhanced collective cell motility results in faster cell segregation leading to the formation of more extensive patterns. The growth of the characteristic scale of patterns generally follows an algebraic scaling law with exponent values up to 0.74 in the presence of collective motion, compared to significantly smaller exponents in case of diffusive motion.

  15. HOXB4 Promotes Hemogenic Endothelium Formation without Perturbing Endothelial Cell Development

    Directory of Open Access Journals (Sweden)

    Nadine Teichweyde

    2018-03-01

    Full Text Available Summary: Generation of hematopoietic stem cells (HSCs from pluripotent stem cells, in vitro, holds great promise for regenerative therapies. Primarily, this has been achieved in mouse cells by overexpression of the homeotic selector protein HOXB4. The exact cellular stage at which HOXB4 promotes hematopoietic development, in vitro, is not yet known. However, its identification is a prerequisite to unambiguously identify the molecular circuits controlling hematopoiesis, since the activity of HOX proteins is highly cell and context dependent. To identify that stage, we retrovirally expressed HOXB4 in differentiating mouse embryonic stem cells (ESCs. Through the use of Runx1(−/− ESCs containing a doxycycline-inducible Runx1 coding sequence, we uncovered that HOXB4 promoted the formation of hemogenic endothelium cells without altering endothelial cell development. Whole-transcriptome analysis revealed that its expression mediated the upregulation of transcription of core transcription factors necessary for hematopoiesis, culminating in the formation of blood progenitors upon initiation of Runx1 expression. : In this article, Klump and colleagues demonstrate that the human homeotic selector protein HOXB4 promotes ESC-derived hematopoiesis by inducing hemogenic endothelium formation, in vitro. It propels hematopoietic specification by upregulating the transcription of genes essential for hematopoietic development, such as those encoding members of the so-called heptad transcription factors. Keywords: HOXB4, hematopoietic stem cells, hemangioblast, hemogenic endothelium, hematopoietic specification, EHT, RUNX1, pluripotent stem cells

  16. Colonial Bilingual Heritage and Post-Colonial Myths in Cameroon's ...

    African Journals Online (AJOL)

    This article examines Cameroon's bilingual heritage and describes post-colonial attitudes and tendencies towards language and language use in the country's educational system. The intent is to show that Cameroon's bilingual heritage - a colonial legacy - has led to an unnecessary and chaotic national competition among ...

  17. Nonspecific CD8+T Cells and Dendritic Cells/Macrophages Participate in Formation of CD8+T Cell-Mediated Clusters against Malaria Liver-Stage Infection.

    Science.gov (United States)

    Akbari, Masoud; Kimura, Kazumi; Bayarsaikhan, Ganchimeg; Kimura, Daisuke; Miyakoda, Mana; Juriasingani, Smriti; Yuda, Masao; Amino, Rogerio; Yui, Katsuyuki

    2018-04-01

    CD8 + T cells are the major effector cells that protect against malaria liver-stage infection, forming clusters around Plasmodium -infected hepatocytes and eliminating parasites after a prolonged interaction with these hepatocytes. We aimed to investigate the roles of specific and nonspecific CD8 + T cells in cluster formation and protective immunity. To this end, we used Plasmodium berghei ANKA expressing ovalbumin as well as CD8 + T cells from transgenic mice expressing a T cell receptor specific for ovalbumin (OT-I) and CD8 + T cells specific for an unrelated antigen, respectively. While antigen-specific CD8 + T cells were essential for cluster formation, both antigen-specific and nonspecific CD8 + T cells joined the clusters. However, nonspecific CD8 + T cells did not significantly contribute to protective immunity. In the livers of infected mice, specific CD8 + T cells expressed high levels of CD25, compatible with a local, activated effector phenotype. In vivo imaging of the liver revealed that specific CD8 + T cells interact with CD11c + cells around infected hepatocytes. The depletion of CD11c + cells virtually eliminated the clusters in the liver, leading to a significant decrease in protection. These experiments reveal an essential role of hepatic CD11c + dendritic cells and presumably macrophages in the formation of CD8 + T cell clusters around Plasmodium -infected hepatocytes. Once cluster formation is triggered by parasite-specific CD8 + T cells, specific and unrelated activated CD8 + T cells join the clusters in a chemokine- and dendritic cell-dependent manner. Nonspecific CD8 + T cells seem to play a limited role in protective immunity against Plasmodium parasites. Copyright © 2018 American Society for Microbiology.

  18. Archaeal Persisters: Persister Cell Formation as a Stress Response in Haloferax volcanii

    Directory of Open Access Journals (Sweden)

    Julianne Megaw

    2017-08-01

    Full Text Available Persister cells are phenotypic variants within a microbial population, which are dormant and transiently tolerant to stress. Persistence has been studied extensively in bacteria, and in eukaryotes to a limited extent, however, it has never been observed in archaea. Using the model haloarchaeon, Haloferax volcanii DS2, we demonstrated persister cell formation in this domain, with time-kill curves exhibiting a characteristic biphasic pattern following starvation or exposure to lethal concentrations of various biocidal compounds. Repeated challenges of surviving cells showed that, as with bacteria, persister formation in H. volcanii was not heritable. Additionally, as previously shown with bacteria, persister formation in H. volcanii was suppressed by exogenous indole. The addition of spent culture media to assays conducted on planktonic cells showed that H. volcanii-conditioned media stimulated persistence, whereas conditioned media of other haloarchaea or halophilic bacteria did not, suggesting the involvement of a species-specific signal. Using a TLC overlay assay, the quorum sensing bioreporter Agrobacterium tumefaciens ATCC BAA-2240 detected the presence of C4 and C6 acyl homoserine lactone-like signal molecules in a H. volcanii culture extract. While synthetic bacterial AHLs did not induce persistence, this is potentially due to structural differences between bacterial and archaeal signals, and does not discount a quorum sensing component in haloarchaeal persister formation. The observation of persister cell formation by this haloarchaeon may provide some insights into the survival of these organisms in stressful or dynamic environments.

  19. Pectinous cell wall thickenings formation - A common defense strategy of plants to cope with Pb.

    Science.gov (United States)

    Krzesłowska, Magdalena; Rabęda, Irena; Basińska, Aneta; Lewandowski, Michał; Mellerowicz, Ewa J; Napieralska, Anna; Samardakiewicz, Sławomir; Woźny, Adam

    2016-07-01

    Lead, one of the most abundant and hazardous trace metals affecting living organisms, has been commonly detected in plant cell walls including some tolerant plants, mining ecotypes and hyperaccumulators. We have previously shown that in tip growing Funaria sp. protonemata cell wall is remodeled in response to lead by formation of thickenings rich in low-methylesterified pectins (pectin epitope JIM5 - JIM5-P) able to bind metal ions, which accumulate large amounts of Pb. Hence, it leads to the increase of cell wall capacity for Pb compartmentalization. Here we show that diverse plant species belonging to different phyla (Arabidopsis, hybrid aspen, star duckweed), form similar cell wall thickenings in response to Pb. These thickenings are formed in tip growing cells such as the root hairs, and in diffuse growing cells such as meristematic and root cap columella cells of root apices in hybrid aspen and Arabidopsis and in mesophyll cells in star duckweed fronds. Notably, all analyzed cell wall thickenings were abundant in JIM5-P and accumulated high amounts of Pb. In addition, the co-localization of JIM5-P and Pb commonly occurred in these cells. Hence, cell wall thickenings formed the extra compartment for Pb accumulation. In this way plant cells increased cell wall capacity for compartmentalization of this toxic metal, protecting protoplast from its toxicity. As cell wall thickenings occurred in diverse plant species and cell types differing in the type of growth we may conclude that pectinous cell wall thickenings formation is a widespread defense strategy of plants to cope with Pb. Moreover, detection of natural defense strategy, increasing plant cell walls capacity for metal accumulation, reveals a promising direction for enhancing plant efficiency in phytoremediation. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Bmi1 overexpression in the cerebellar granule cell lineage of mice affects cell proliferation and survival without initiating medulloblastoma formation

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    Hourinaz Behesti

    2013-01-01

    BMI1 is a potent inducer of neural stem cell self-renewal and neural progenitor cell proliferation during development and in adult tissue homeostasis. It is overexpressed in numerous human cancers – including medulloblastomas, in which its functional role is unclear. We generated transgenic mouse lines with targeted overexpression of Bmi1 in the cerebellar granule cell lineage, a cell type that has been shown to act as a cell of origin for medulloblastomas. Overexpression of Bmi1 in granule cell progenitors (GCPs led to a decrease in cerebellar size due to decreased GCP proliferation and repression of the expression of cyclin genes, whereas Bmi1 overexpression in postmitotic granule cells improved cell survival in response to stress by altering the expression of genes in the mitochondrial cell death pathway and of Myc and Lef-1. Although no medulloblastomas developed in ageing cohorts of transgenic mice, crosses with Trp53−/− mice resulted in a low incidence of medulloblastoma formation. Furthermore, analysis of a large collection of primary human medulloblastomas revealed that tumours with a BMI1high TP53low molecular profile are significantly enriched in Group 4 human medulloblastomas. Our data suggest that different levels and timing of Bmi1 overexpression yield distinct cellular outcomes within the same cellular lineage. Importantly, Bmi1 overexpression at the GCP stage does not induce tumour formation, suggesting that BMI1 overexpression in GCP-derived human medulloblastomas probably occurs during later stages of oncogenesis and might serve to enhance tumour cell survival.

  1. Colony analysis and deep learning uncover 5-hydroxyindole as an inhibitor of gliding motility and iridescence in Cellulophaga lytica.

    Science.gov (United States)

    Chapelais-Baron, Maylis; Goubet, Isabelle; Péteri, Renaud; Pereira, Maria de Fatima; Mignot, Tâm; Jabveneau, Apolline; Rosenfeld, Eric

    2018-03-01

    Iridescence is an original type of colouration that is relatively widespread in nature but has been either incompletely described or entirely neglected in prokaryotes. Recently, we reported a brilliant 'pointillistic' iridescence in agar-grown colony biofilms of Cellulophaga lytica and some other marine Flavobacteria that exhibit gliding motility. Bacterial iridescence is created by a unique self-organization of sub-communities of cells, but the mechanisms underlying such living photonic crystals are unknown. In this study, we used Petri dish assays to screen a large panel of potential activators or inhibitors of C. lytica's iridescence. Derivatives potentially interfering with quorum-sensing and other communication or biofilm formation processes were tested, as well as metabolic poisons or algal exoproducts. We identified an indole derivative, 5-hydroxyindole (5HI, 250 µM) which inhibited both gliding and iridescence at the colonial level. 5HI did not affect growth or cell respiration. At the microscopic level, phase-contrast imaging confirmed that 5HI inhibits the gliding motility of cells. Moreover, the lack of iridescence correlated with a perturbation of self-organization of the cell sub-communities in both the WT and a gliding-negative mutant. This effect was proved using recent advances in machine learning (deep neuronal networks). In addition to its effect on colony biofilms, 5HI was found to stimulate biofilm formation in microplates. Our data are compatible with possible roles of 5HI or marine analogues in the eco-biology of iridescent bacteria.

  2. Combination cisplatin and sulforaphane treatment reduces proliferation, invasion, and tumor formation in epidermal squamous cell carcinoma.

    Science.gov (United States)

    Kerr, Candace; Adhikary, Gautam; Grun, Daniel; George, Nicholas; Eckert, Richard L

    2018-01-01

    Epidermal squamous cell carcinoma is an extremely common type of cancer. Early tumors can be successfully treated by surgery, but recurrent disease is aggressive and resistant to therapy. Cisplatin is often used as a treatment, but the outcome is rarely satisfactory. For this reason new strategies are required. Sulforaphane is a diet-derived cancer prevention agent that is effective in suppressing tumor growth in animal models of skin cancer. We monitored the efficacy of sulforaphane and cisplatin as a combined therapy for squamous cell carcinoma. Both agents suppress cell proliferation, growth of cancer stem cell spheroids, matrigel invasion and migration of SCC-13 and HaCaT cells, and combination treatment is more efficient. In addition, SCC-13 cell derived cancer stem cells are more responsive to these agents than non-stem cancer cells. Both agents suppress tumor formation, but enhanced suppression is observed with combined treatment. Moreover, both agents reduce the number of tumor-resident cancer stem cells. SFN treatment of cultured cells or tumors increases apoptosis and p21 Cip1 level, and both agents increase tumor apoptosis. We suggest that combined therapy with sulforaphane and cisplatin is efficient in suppressing tumor formation and may be a treatment option for advanced epidermal squamous cell carcinoma. © 2017 Wiley Periodicals, Inc.

  3. The adaptor molecule SAP plays essential roles during invariant NKT cell cytotoxicity and lytic synapse formation.

    Science.gov (United States)

    Das, Rupali; Bassiri, Hamid; Guan, Peng; Wiener, Susan; Banerjee, Pinaki P; Zhong, Ming-Chao; Veillette, André; Orange, Jordan S; Nichols, Kim E

    2013-04-25

    The adaptor molecule signaling lymphocytic activation molecule-associated protein (SAP) plays critical roles during invariant natural killer T (iNKT) cell ontogeny. As a result, SAP-deficient humans and mice lack iNKT cells. The strict developmental requirement for SAP has made it difficult to discern its possible involvement in mature iNKT cell functions. By using temporal Cre recombinase-mediated gene deletion to ablate SAP expression after completion of iNKT cell development, we demonstrate that SAP is essential for T-cell receptor (TCR)-induced iNKT cell cytotoxicity against T-cell and B-cell leukemia targets in vitro and iNKT-cell-mediated control of T-cell leukemia growth in vivo. These findings are not restricted to the murine system: silencing RNA-mediated suppression of SAP expression in human iNKT cells also significantly impairs TCR-induced cytolysis. Mechanistic studies reveal that iNKT cell killing requires the tyrosine kinase Fyn, a known SAP-binding protein. Furthermore, SAP expression is required within iNKT cells to facilitate their interaction with T-cell targets and induce reorientation of the microtubule-organizing center to the immunologic synapse (IS). Collectively, these studies highlight a novel and essential role for SAP during iNKT cell cytotoxicity and formation of a functional IS.

  4. An improved model for nucleation-limited ice formation in living cells during freezing.

    Directory of Open Access Journals (Sweden)

    Jingru Yi

    Full Text Available Ice formation in living cells is a lethal event during freezing and its characterization is important to the development of optimal protocols for not only cryopreservation but also cryotherapy applications. Although the model for probability of ice formation (PIF in cells developed by Toner et al. has been widely used to predict nucleation-limited intracellular ice formation (IIF, our data of freezing Hela cells suggest that this model could give misleading prediction of PIF when the maximum PIF in cells during freezing is less than 1 (PIF ranges from 0 to 1. We introduce a new model to overcome this problem by incorporating a critical cell volume to modify the Toner's original model. We further reveal that this critical cell volume is dependent on the mechanisms of ice nucleation in cells during freezing, i.e., surface-catalyzed nucleation (SCN and volume-catalyzed nucleation (VCN. Taken together, the improved PIF model may be valuable for better understanding of the mechanisms of ice nucleation in cells during freezing and more accurate prediction of PIF for cryopreservation and cryotherapy applications.

  5. Coilin phosphomutants disrupt Cajal body formation, reduce cell proliferation and produce a distinct coilin degradation product.

    Directory of Open Access Journals (Sweden)

    Zunamys I Carrero

    Full Text Available Coilin is a nuclear phosphoprotein that accumulates in Cajal bodies (CBs. CBs participate in ribonucleoprotein and telomerase biogenesis, and are often found in cells with high transcriptional demands such as neuronal and cancer cells, but can also be observed less frequently in other cell types such as fibroblasts. Many proteins enriched within the CB are phosphorylated, but it is not clear what role this modification has on the activity of these proteins in the CB. Coilin is considered to be the CB marker protein and is essential for proper CB formation and composition in mammalian cells. In order to characterize the role of coilin phosphorylation on CB formation, we evaluated various coilin phosphomutants using transient expression. Additionally, we generated inducible coilin phosphomutant cell lines that, when used in combination with endogenous coilin knockdown, allow for the expression of the phosphomutants at physiological levels. Transient expression of all coilin phosphomutants except the phosphonull mutant (OFF significantly reduces proliferation. Interestingly, a stable cell line induced to express the coilin S489D phosphomutant displays nucleolar accumulation of the mutant and generates a N-terminal degradation product; neither of which is observed upon transient expression. A N-terminal degradation product and nucleolar localization are also observed in a stable cell line induced to express a coilin phosphonull mutant (OFF. The nucleolar localization of the S489D and OFF coilin mutants observed in the stable cell lines is decreased when endogenous coilin is reduced. Furthermore, all the phosphomutant cells lines show a significant reduction in CB formation when compared to wild-type after endogenous coilin knockdown. Cell proliferation studies on these lines reveal that only wild-type coilin and the OFF mutant are sufficient to rescue the reduction in proliferation associated with endogenous coilin depletion. These results emphasize

  6. Inhibition of Blumeria graminis germination and germling development within colonies of oat mildew

    DEFF Research Database (Denmark)

    Carver, T.L.W.; Roberts, P.C.; Thomas, B.J.

    2001-01-01

    Germination by Blumeria graminis. DC Speer ff. spp. avenae, hordei and tritici, was greatly suppressed when conidia fell within colonies of ff. spp. avenae or hordei established on susceptible oat or barley, respectively. On healthy oat or barley, and when distant from powdery mildew, colonies. all...... ff. spp. formed normal appressoria. This was also true When conidia germinated within established barley mildew colonies. Within barley mildew colonies, appressoria of f. sp. hordei penetrated epidermal cells formed haustoria more frequently than appressoria distant from colonies. Similarly, ff. spp....... avenae and tritici, normally unable to infect barley. frequently penetrated epidermal cells subtending established barley mildew colonies. Thus, colony, establishment induced barley epidermal cell accessibility, even to non-pathogenic ff. spp, In contrast. when all three ff. spp. germinated within...

  7. Plant metabolism and cell wall formation in space (microgravity) and on Earth

    Science.gov (United States)

    Lewis, Norman G.

    1994-01-01

    Variations in cell wall chemistry provide vascular plants with the ability to withstand gravitational forces, as well as providing facile mechanisms for correctional responses to various gravitational stimuli, e.g., in reaction wood formation. A principal focus of our current research is to precisely and systematically dissect the essentially unknown mechanism(s) of vascular plant cell wall assembly, particularly with respect to formation of its phenolic constituents, i.e., lignins and suberins, and how gravity impacts upon these processes. Formation of these phenolic polymers is of particular interest, since it appears that elaboration of their biochemical pathways was essential for successful land adaptation. By extrapolation, we are also greatly intrigued as to how the microgravity environment impacts upon 'normal' cell wall assembly mechanisms/metabolism.

  8. Spatial Arrangement of Colonies in Intact Biofilms from a Model Cooling Water System

    Directory of Open Access Journals (Sweden)

    Michael Taylor

    2013-01-01

    Full Text Available There is disagreement among microbiologists about whether Legionella requires a protozoan host in order to replicate. This research sought to determine where in biofilm Legionellae are found and whether all biofilm associated Legionella would be located within protozoan hosts. While it is accepted that Legionella colonizes biofilm, its life cycle and nutritional fastidiousness suggest that Legionella employs multiple survival strategies to persist within microbial systems. Fluorescent in situ hybridization (FISH and confocal laser scanning microscopy (CLSM demonstrated an undulating biofilm surface architecture and a roughly homogenous distribution of heterotrophic bacteria with clusters of protozoa. Legionella displayed 3 distinct spatial arrangements either contained within or directly associated with protozoa, or dispersed in loosely associated clusters or in tightly packed aggregations of cells forming dense colonial clusters. The formation of discreet clusters of tightly packed Legionella suggests that colony formation is influenced by specific environmental conditions allowing for limited extracellular replication. This work represents the first time that an environmentally representative, multispecies biofilm containing Legionella has been fluorescently tagged and Legionella colony morphology noted within a complex microbial system.

  9. The association between circulating endothelial progenitor cells and coronary collateral formation.

    Science.gov (United States)

    Tokgözoğlu, Lale; Yorgun, Hikmet; Gürses, Kadri Murat; Canpolat, Uğur; Ateş, Ahmet Hakan; Tülümen, Erol; Kaya, Ergün Barış; Aytemir, Kudret; Kabakçı, Giray; Tuncer, Murat; Oto, Ali

    2011-12-01

    We investigated the relationship between coronary collateral formation and circulating endothelial progenitor cells (EPC) in patients undergoing coronary angiography. Circulating CD133(+)/34(+) and CD34(+)/KDR(+) EPCs were determined in 68 patients (normal coronary vessels in 24 patients and coronary artery disease (CAD) in 44 patients) (age: 58.7 ± 10.1, 64.7% male). Circulating EPCs were higher among patients with normal coronary vessels compared to patients with CAD for CD133(+)/34(+) (p collateral formation (p collateral formation after adjustment for other cardiovascular risk factors and extent of CAD (p = 0.037). In patients with severe coronary stenosis, those with increased circulating EPCs had better collateral formation compared to those with lower EPC counts. Our findings implicate that in addition to presence of critical stenosis, intact response of bone marrow is necessary for collateral formation in CAD. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  10. Multiple regions of Crumbs3 are required for tight junction formation in MCF10A cells.

    Science.gov (United States)

    Fogg, Vanessa C; Liu, Chia-Jen; Margolis, Ben

    2005-07-01

    The formation and maintenance of tight junctions is essential for the development of epithelial cell polarity. Recently, a number of conserved polarity-regulating proteins have been shown to localize to epithelial tight junctions, and to play a role in the regulation of tight junction formation. The Crumbs3/PALS1/PATJ protein complex localizes at epithelial tight junctions and interacts with the polarity-regulating protein complex of Par6/Par3/aPKC. Overexpression of Crumbs3 in MDCKII cells leads to a delay in tight junction formation in these cells, suggesting a role in the regulation of tight junction development. Here we report new evidence that Crumbs3 indeed plays an essential role in tight junction formation. Mammary MCF10A cells express little endogenous Crumbs3 and fail to form tight junctions when grown under standard tissue culture conditions. The staining pattern of ZO-1, a tight junction marker, is fragmented, and other tight junction markers show either fragmented junctional expression or diffuse cytoplasmic staining. Expression of exogenous Crumbs3 induces the formation of tight junction structures marked by smooth, continuous ZO-1 staining at apical cell-cell junctions. A number of other tight junction markers, including claudin-1 and occludin, are also recruited to these junctions. Analysis by transmission electron microscopy and measurements of the transepithelial electrical resistance confirm that these structures are functional tight junctions. Mutations in either the Crumbs3 PDZ binding motif or the putative FERM binding motif lead to defects in the ability of Crumbs3 to promote tight junction development. Our results suggest that Crumbs3 plays an important role in epithelial tight junction formation, and also provide the first known functional role for the mammalian Crumbs FERM binding domain.

  11. Colony induction and growth inhibition in Desmodesmus quadrispina (Chlorococcales) by allelochemicals released from the filamentous alga Uronema confervicolum (Ulotrichales).

    Science.gov (United States)

    Leflaive, Joséphine; Lacroix, Gérard; Nicaise, Yvan; Ten-Hage, Loïc

    2008-06-01

    In biofilms, the competition between microorganisms for light, nutrients and space is extreme. Moreover, planktonic algae can be considered as competitors insofar as they decrease the available light for the benthic algae. One of the strategies employed by microorganisms to eliminate competitors is the release of inhibiting compounds, a process known as allelopathy. Here we demonstrate that a benthic/epiphytic alga, Uronema confervicolum, produces allelopathic compounds that induce oxidative stress and growth inhibition in the planktonic Desmodesmus quadrispina. Some of these compounds can also trigger the formation of colony in D. quadrispina. As colonies have higher sedimentation rates than unicells, their induction by U. confervicolum might decrease shading. This study is the first report of colony induction in the context of alga-alga interaction. Our results also suggest the implication of mitogen-activated protein (MAP) kinases in the transduction of the signal leading to the formation of reactive oxygen species in the cells. A comparison with allelochemicals from another planktonic green alga, Monoraphidium aff. dybowski, emphasizes the specificity of colony induction by U. confervicolum, in contrast with oxidative stress which is induced by several compounds. The reciprocal production of inhibiting compounds by D. quadrispina makes this interaction an interesting example of co-evolution between two microorganisms belonging to different compartments of the ecosystem.

  12. Post-Colonial Theory and Action Research

    Science.gov (United States)

    Parsons, Jim B.; Harding, Kelly J.

    2011-01-01

    This essay explores connections between post-colonial theory and action research. Post-colonial theory is committed to addressing the plague of colonialism. Action research, at its core, promises to problematize uncontested "colonial" hegemonies of any form. Both post-colonial theory and action research engage dialogic, critically reflective and…

  13. The Lncrna-TUG1/EZH2 Axis Promotes Pancreatic Cancer Cell Proliferation, Migration and EMT Phenotype Formation Through Sponging Mir-382.

    Science.gov (United States)

    Zhao, Liang; Sun, Hongwei; Kong, Hongru; Chen, Zongjing; Chen, Bicheng; Zhou, Mengtao

    2017-01-01

    Pancreatic carcinoma (PC) is the one of the most common and malignant cancers worldwide. LncRNA taurine upregulated gene 1 (TUG1) was initially identified as a transcript upregulated by taurine, and the abnormal expression of TUG1 has been reported in many cancers. However, the biological role and molecular mechanism of TUG1 in PC still needs further investigation. Quantitative real-time PCR (qRT-PCR) was performed to measure the expression of TUG1 in PC cell lines and tissues. MTT and colony formation assays were used to measure the effect of TUG1 on cell proliferation. A wound healing assay, transwell assay and western blot assay were employed to determine the effect of TUG1 on cell migration and the epithelial mesenchymal transition (EMT) phenotype. RNA-binding protein immunoprecipitation (RIP) and a biotin-avidin pulldown system were performed to confirm the interaction between miR-328 and TUG1. A gene expression array analysis using clinical samples and RT-qPCR suggested that enhancer of zeste homolog 2 (EZH2) was a target of miR-382 in PC. In this study, we reported that TUG1 was overexpressed in PC tissues and cell lines, and high expression of TUG1 predicted poor prognosis. Further experiments revealed that overexpressed TUG1 promoted cell proliferation, migration and contributed to EMT formation, whereas silenced TUG1 led to opposing results. Additionally, luciferase reporter assays, an RIP assay and an RNA-pulldown assay demonstrated that TUG1 could competitively sponge miR-382 and thereby regulate EZH2. Collectively, these findings revealed that TUG1 functions as an oncogenic lncRNA that promotes tumor progression, at least partially, by functioning as an endogenous 'sponge' and competing for miR-382 binding to the miRNA target EZH2. © 2017 The Author(s). Published by S. Karger AG, Basel.

  14. The Lncrna-TUG1/EZH2 Axis Promotes Pancreatic Cancer Cell Proliferation, Migration and EMT Phenotype Formation Through Sponging Mir-382

    Directory of Open Access Journals (Sweden)

    Liang Zhao

    2017-08-01

    Full Text Available Background/Aims: Pancreatic carcinoma (PC is the one of the most common and malignant cancers worldwide. LncRNA taurine upregulated gene 1 (TUG1 was initially identified as a transcript upregulated by taurine, and the abnormal expression of TUG1 has been reported in many cancers. However, the biological role and molecular mechanism of TUG1 in PC still needs further investigation. Methods: Quantitative real-time PCR (qRT-PCR was performed to measure the expression of TUG1 in PC cell lines and tissues. MTT and colony formation assays were used to measure the effect of TUG1 on cell proliferation. A wound healing assay, transwell assay and western blot assay were employed to determine the effect of TUG1 on cell migration and the epithelial mesenchymal transition (EMT phenotype. RNA-binding protein immunoprecipitation (RIP and a biotin-avidin pulldown system were performed to confirm the interaction between miR-328 and TUG1. A gene expression array analysis using clinical samples and RT-qPCR suggested that enhancer of zeste homolog 2 (EZH2 was a target of miR-382 in PC. Results: In this study, we reported that TUG1 was overexpressed in PC tissues and cell lines, and high expression of TUG1 predicted poor prognosis. Further experiments revealed that overexpressed TUG1 promoted cell proliferation, migration and contributed to EMT formation, whereas silenced TUG1 led to opposing results. Additionally, luciferase reporter assays, an RIP assay and an RNA-pulldown assay demonstrated that TUG1 could competitively sponge miR-382 and thereby regulate EZH2. Conclusion: Collectively, these findings revealed that TUG1 functions as an oncogenic lncRNA that promotes tumor progression, at least partially, by functioning as an endogenous ‘sponge’ and competing for miR-382 binding to the miRNA target EZH2.

  15. Formation of IgE-binding factors by human T-cell hybridomas.

    OpenAIRE

    Huff, T F; Ishizaka, K

    1984-01-01

    Normal human T cells that proliferated in the presence of interleukin 2 (IL-2) formed IgE-binding factors when incubated with human IgE. These cells were then fused with a mutant of the human T-cell line CEM. Incubation of five hybridomas with human IgE or culture of the cells in IgE-coated wells resulted in the formation of IgE-binding factors. One hour of incubation with 10 micrograms of human IgE per ml was sufficient to induce the hybridomas to form IgE-binding factors. Polymerized IgE wa...

  16. Guided extracellular matrix formation from fibroblast cells cultured on bio-inspired configurable multiscale substrata

    Directory of Open Access Journals (Sweden)

    Won-Gyu Bae

    2015-12-01

    Full Text Available Engineering complex extracellular matrix (ECM is an important challenge for cell and tissue engineering applications as well as for understanding fundamental cell biology. We developed the methodology for fabrication of precisely controllable multiscale hierarchical structures using capillary force lithography in combination with original wrinkling technique for the generation of well-defined native ECM-like platforms by culturing fibroblast cells on the multiscale substrata [1]. This paper provides information on detailed characteristics of polyethylene glycol-diacrylate multiscale substrata. In addition, a possible model for guided extracellular matrix formation from fibroblast cells cultured on bio-inspired configurable multiscale substrata is proposed.

  17. Methods for studying biofilm formation: flow cells and confocal laser scanning microscopy

    DEFF Research Database (Denmark)

    Tolker-Nielsen, Tim; Sternberg, Claus

    2014-01-01

    In this chapter methods for growing and analyzing biofilms under hydrodynamic conditions in flow cells are described. Use of flow cells allows for direct microscopic investigation of biofilm formation. The flow in these chambers is essentially laminar, which means that the biofilms can be grown...... under highly controlled conditions, and that perturbations such as addition of antibiotics or change of the growth medium can be done efficiently at a defined time point. The protocol includes construction of the flow cell and the bubble trap, assembly and sterilization of the flow cell system...

  18. MECHANICAL VIBRATION INHIBITS OSTEOCLAST FORMATION BY REDUCING DC-STAMP RECEPTOR EXPRESSION IN OSTEOCLAST PRECURSOR CELLS

    Science.gov (United States)

    Kulkarni, R.N.; Voglewede, P.A.; Liu, D.

    2014-01-01

    It is well known that physical inactivity leads to loss of muscle mass, but it also causes bone loss. Mechanistically, osteoclastogenesis and bone resorption have recently been shown to be regulated by vibration. However, the underlying mechanism behind the inhibition of osteoclast formation is yet unknown. Therefore, we investigated whether mechanical vibration of osteoclast precursor cells affects osteoclast formation by the involvement of fusion-related molecules such as dendritic cell-specific transmembrane protein (DC-STAMP), and P2X7 receptor (P2X7R). RAW264.7 (a murine osteoclastic-like cell line) cells were treated with 20 ng/ml receptor activator of NF-κB ligand (RANKL). For 3 consecutive days, the cells were subjected to 1 hour of mechanical vibration with 20 µm displacement at a frequency of 4 Hz and compared to the control cells that were treated under the same condition but without the vibration. After 5 days of culture, osteoclast formation was determined. Gene expression of DC-STAMP and P2X7R by RAW264.7 cells were determined after 1 hour mechanical vibration, while protein production of the DC-STAMP was determined after 6 hours of post incubation after vibration. As a result, mechanical vibration of RAW264.7 cells inhibited the formation of osteoclasts. Vibration down-regulated DC-STAMP gene expression by 1.6-fold in the presence of RANKL and by 1.4-fold in the absence of RANKL. Additionally, DC-STAMP protein production was also down-regulated by 1.4-fold in the presence of RANKL and by 1.2-fold in the absence of RANKL in RAW264.7 cells in response to mechanical vibration. However, vibration did not affect P2X7R gene expression. Mouse anti-DC-STAMP antibody inhibited osteoclast formation in the absence of vibration. Our results suggest that mechanical vibration of osteoclast precursor cells reduce DC-STAMP expression in osteoclast precursor cells leading to the inhibition of osteoclast formation. PMID:23994170

  19. Mechanical vibration inhibits osteoclast formation by reducing DC-STAMP receptor expression in osteoclast precursor cells.

    Science.gov (United States)

    Kulkarni, Rishikesh N; Voglewede, Philip A; Liu, Dawei

    2013-12-01

    It is well known that physical inactivity leads to loss of muscle mass, but it also causes bone loss. Mechanistically, osteoclastogenesis and bone resorption have recently been shown to be regulated by vibration. However, the underlying mechanism behind the inhibition of osteoclast formation is yet unknown. Therefore, we investigated whether mechanical vibration of osteoclast precursor cells affects osteoclast formation by the involvement of fusion-related molecules such as dendritic cell-specific transmembrane protein (DC-STAMP) and P2X7 receptor (P2X7R). RAW264.7 (a murine osteoclastic-like cell line) cells were treated with 20ng/ml receptor activator of NF-κB ligand (RANKL). For 3 consecutive days, the cells were subjected to 1h of mechanical vibration with 20μm displacement at a frequency of 4Hz and compared to the control cells that were treated under the same condition but without the vibration. After 5days of culture, osteoclast formation was determined. Gene expression of DC-STAMP and P2X7R by RAW264.7 cells was determined after 1h of mechanical vibration, while protein production of the DC-STAMP was determined after 6h of postincubation after vibration. As a result, mechanical vibration of RAW264.7 cells inhibited the formation of osteoclasts. Vibration down-regulated DC-STAMP gene expression by 1.6-fold in the presence of RANKL and by 1.4-fold in the absence of RANKL. Additionally, DC-STAMP protein production was also down-regulated by 1.4-fold in the presence of RANKL and by 1.2-fold in the absence of RANKL in RAW264.7 cells in response to mechanical vibration. However, vibration did not affect P2X7R gene expression. Mouse anti-DC-STAMP antibody inhibited osteoclast formation in the absence of vibration. Our results suggest that mechanical vibration of osteoclast precursor cells reduces DC-STAMP expression in osteoclast precursor cells leading to the inhibition of osteoclast formation. © 2013 Elsevier Inc. All rights reserved.

  20. Effect of policosanol on foam-cell formation in carrageenan-induced granulomas in rats.

    Science.gov (United States)

    Noa, M; de la Rosa, M C; Más, R

    1996-03-01

    Policosanol is a new cholesterol-lowering drug isolated and purified from sugar-cane wax, which prevents the development of lipofundin-induced lesions and foam-cell formation in New Zealand rabbits and Wistar rats. This study was conducted to examine the effects of policosanol on foam-cell formation in carrageenan-induced granulomas in rats. Eighteen Wistar rats were randomly distributed in three experimental groups which received orally for 20 days Tween 20 H2O as vehicle (control group) or policosanol at 2.5 or 25 mg kg-1. At the 11th day, lipofundin was injected intraperitoneally for 8 days to induce formation of foam cells in the granuloma. At day 13, carrageenan was injected subcutaneously for granuloma induction and seven days later animals were killed. A significant reduction of the foam-cell formation in granulomas of policosanol-treated rats was observed. It is concluded that policosanol prevents the development of foam cells in carrageenan-induced granulomas (extravascular medium) in rats.

  1. Three-dimensional bioprinting of embryonic stem cells directs highly uniform embryoid body formation

    International Nuclear Information System (INIS)

    Ouyang, Liliang; Yao, Rui; Mao, Shuangshuang; Sun, Wei; Chen, Xi; Na, Jie

    2015-01-01

    With the ability to manipulate cells temporarily and spatially into three-dimensional (3D) tissue-like construct, 3D bioprinting technology was used in many studies to facilitate the recreation of complex cell niche and/or to better understand the regulation of stem cell proliferation and differentiation by cellular microenvironment factors. Embryonic stem cells (ESCs) have the capacity to differentiate into any specialized cell type of the animal body, generally via the formation of embryoid body (EB), which mimics the early stages of embryogenesis. In this study, extrusion-based 3D bioprinting technology was utilized for biofabricating ESCs into 3D cell-laden construct. The influence of 3D printing parameters on ESC viability, proliferation, maintenance of pluripotency and the rule of EB formation was systematically studied in this work. Results demonstrated that ESCs were successfully printed with hydrogel into 3D macroporous construct. Upon process optimization, about 90% ESCs remained alive after the process of bioprinting and cell-laden construct formation. ESCs continued proliferating into spheroid EBs in the hydrogel construct, while retaining the protein expression and gene expression of pluripotent markers, like octamer binding transcription factor 4, stage specific embryonic antigen 1 and Nanog. In this novel technology, EBs were formed through cell proliferation instead of aggregation, and the quantity of EBs was tuned by the initial cell density in the 3D bioprinting process. This study introduces the 3D bioprinting of ESCs into a 3D cell-laden hydrogel construct for the first time and showed the production of uniform, pluripotent, high-throughput and size-controllable EBs, which indicated strong potential in ESC large scale expansion, stem cell regulation and fabrication of tissue-like structure and drug screening studies. (paper)

  2. Spontaneous Formation of Tumorigenic Hybrids between Breast Cancer and Multipotent Stromal Cells Is a Source of Tumor Heterogeneity

    OpenAIRE

    Rappa, Germana; Mercapide, Javier; Lorico, Aurelio

    2012-01-01

    Breast cancer progression involves cancer cell heterogeneity, with generation of invasive/metastatic breast cancer cells within populations of nonmetastatic cells of the primary tumor. Sequential genetic mutations, epithelial-to-mesenchymal transition, interaction with local stroma, and formation of hybrids between cancer cells and normal bone marrow–derived cells have been advocated as tumor progression mechanisms. We report herein the spontaneous in vitro formation of heterotypic hybrids be...

  3. The effect of stem cell proliferation regulators demonstrated with an in vitro assay.

    Science.gov (United States)

    Pragnell, I B; Wright, E G; Lorimore, S A; Adam, J; Rosendaal, M; DeLamarter, J F; Freshney, M; Eckmann, L; Sproul, A; Wilkie, N

    1988-07-01

    Spleen colony formation after transplantation of bone marrow cells into irradiated mice has been used as an assay for hematopoietic stem cells (CFU-S), but has serious limitations intrinsic to an in vivo assay. In this report we describe experiments using an in vitro clonogenic assay that is especially suitable for studies of stem cell regulation as defined growth factors and normal untreated bone marrow can be used. We have demonstrated that the colony-forming cells have proliferative properties in common with CFU-S and respond to specific proliferation regulators previously detected using the spleen colony assay.

  4. MUC16 provides immune protection by inhibiting synapse formation between NK and ovarian tumor cells

    Directory of Open Access Journals (Sweden)

    Migneault Martine

    2010-01-01

    Full Text Available Abstract Background Cancer cells utilize a variety of mechanisms to evade immune detection and attack. Effective immune detection largely relies on the formation of an immune synapse which requires close contact between immune cells and their targets. Here, we show that MUC16, a heavily glycosylated 3-5 million Da mucin expressed on the surface of ovarian tumor cells, inhibits the formation of immune synapses between NK cells and ovarian tumor targets. Our results indicate that MUC16-mediated inhibition of immune synapse formation is an effective mechanism employed by ovarian tumors to evade immune recognition. Results Expression of low levels of MUC16 strongly correlated with an increased number of conjugates and activating immune synapses between ovarian tumor cells and primary naïve NK cells. MUC16-knockdown ovarian tumor cells were more susceptible to lysis by primary NK cells than MUC16 expressing controls. This increased lysis was not due to differences in the expression levels of the ligands for the activating receptors DNAM-1 and NKG2D. The NK cell leukemia cell line (NKL, which does not express KIRs but are positive for DNAM-1 and NKG2D, also conjugated and lysed MUC16-knockdown cells more efficiently than MUC16 expressing controls. Tumor cells that survived the NKL challenge expressed higher levels of MUC16 indicating selective lysis of MUC16low targets. The higher csMUC16 levels on the NKL resistant tumor cells correlated with more protection from lysis as compared to target cells that were never exposed to the effectors. Conclusion MUC16, a carrier of the tumor marker CA125, has previously been shown to facilitate ovarian tumor metastasis and inhibits NK cell mediated lysis of tumor targets. Our data now demonstrates that MUC16 expressing ovarian cancer cells are protected from recognition by NK cells. The immune protection provided by MUC16 may lead to selective survival of ovarian cancer cells that are more efficient in

  5. Secondary cell wall formation in Cryptococcus neoformans as a rescue mechanism against acid-induced autolysis.

    Science.gov (United States)

    Farkas, Vladimír; Takeo, Kanji; Maceková, Danka; Ohkusu, Misako; Yoshida, Soichi; Sipiczki, Matthias

    2009-03-01

    Growth of the opportunistic yeast pathogen Cryptococcus neoformans in a synthetic medium containing yeast nitrogen base and 1.0-3.0% glucose is accompanied by spontaneous acidification of the medium, with its pH decreasing from the initial 5.5 to around 2.5 in the stationary phase. During the transition from the late exponential to the stationary phase of growth, many cells died as a consequence of autolytic erosion of their cell walls. Simultaneously, there was an increase in an ecto-glucanase active towards beta-1,3-glucan and having a pH optimum between pH 3.0 and 3.5. As a response to cell wall degradation, some cells developed an unusual survival strategy by forming 'secondary' cell walls underneath the original ones. Electron microscopy revealed that the secondary cell walls were thicker than the primary ones, exposing bundles of polysaccharide microfibrils only partially masked by an amorphous cell wall matrix on their surfaces. The cells bearing secondary cell walls had a three to five times higher content of the alkali-insoluble cell wall polysaccharides glucan and chitin, and their chitin/glucan ratio was about twofold higher than in cells from the logarithmic phase of growth. The cell lysis and the formation of the secondary cell walls could be suppressed by buffering the growth medium between pH 4.5 and 6.5.

  6. Survivin Modulates Squamous Cell Carcinoma-Derived Stem-Like Cell Proliferation, Viability and Tumor Formation in Vivo

    Directory of Open Access Journals (Sweden)

    Roberta Lotti

    2016-01-01

    Full Text Available Squamous Cell Carcinoma-derived Stem-like Cells (SCC-SC originate from alterations in keratinocyte stem cells (KSC gene expression and sustain tumor development, invasion and recurrence. Since survivin, a KSC marker, is highly expressed in SCC-SC, we evaluate its role in SCC-SC cell growth and SCC models. Survivin silencing by siRNA decreases clonal growth of SCC keratinocytes and viability of total, rapidly adhering (RAD and non-RAD (NRAD cells from primary SCC. Similarly, survivin silencing reduces the expression of stem cell markers (OCT4, NOTCH1, CD133, β1-integrin, while it increases the level of differentiation markers (K10, involucrin. Moreover, survivin silencing improves the malignant phenotype of SCC 3D-reconstruct, as demonstrated by reduced epidermal thickness, lower Ki-67 positive cell number, and decreased expression of MMP9 and psoriasin. Furthermore, survivin depletion by siRNA in RasG12V-IκBα-derived tumors leads to smaller tumor formation characterized by lower mitotic index and reduced expression of the tumor-associated marker HIF1α, VEGF and CD51. Therefore, our results indicate survivin as a key gene in regulating SCC cancer stem cell formation and cSCC development.

  7. Formation of gut-like structures in vitro from mouse embryonic stem cells.

    Science.gov (United States)

    Torihashi, Shigeko

    2006-01-01

    Embryonic stem (ES) cells have the potential to differentiate into all cell types originating from the three germ layers; however, there are still few reports about the formation of functional organs from embryonic stem cells. Recently, we reported that by hanging drops of mouse ES cells, embryoid bodies (EBs) formed gut-like structures in vitro composed of three layers corresponding to the epithelium, lamina propria, and musculature. The morphological features and the process of formation are similar to gut and its organogenesis in vivo. Thus, this is a good model for development of the gut and a useful tool for analysis of the factors required for gut organogenesis. The protocol basically involves a method of hanging drops to make EBs, which are then plated on coated dishes for outgrowth. EBs develop to form gut-like structures when induced to spontaneously enter a program of differentiation in vitro without addition of any extrinsic factors.

  8. Sequential Salinomycin Treatment Results in Resistance Formation through Clonal Selection of Epithelial-Like Tumor Cells

    Directory of Open Access Journals (Sweden)

    Florian Kopp

    2014-12-01

    Full Text Available Acquiring therapy resistance is one of the major obstacles in the treatment of patients with cancer. The discovery of the cancer stem cell (CSC–specific drug salinomycin raised hope for improved treatment options by targeting therapy-refractory CSCs and mesenchymal cancer cells. However, the occurrence of an acquired salinomycin resistance in tumor cells remains elusive. To study the formation of salinomycin resistance, mesenchymal breast cancer cells were sequentially treated with salinomycin in an in vitro cell culture assay, and the resulting differences in gene expression and salinomycin susceptibility were analyzed. We demonstrated that long-term salinomycin treatment of mesenchymal cancer cells resulted in salinomycin-resistant cells with elevated levels of epithelial markers, such as E-cadherin and miR-200c, a decreased migratory capability, and a higher susceptibility to the classic chemotherapeutic drug doxorubicin. The formation of salinomycin resistance through the acquisition of epithelial traits was further validated by inducing mesenchymal-epithelial transition through an overexpression of miR-200c. The transition from a mesenchymal to a more epithelial-like phenotype of salinomycin-treated tumor cells was moreover confirmed in vivo, using syngeneic and, for the first time, transgenic mouse tumor models. These results suggest that the acquisition of salinomycin resistance through the clonal selection of epithelial-like cancer cells could become exploited for improved cancer therapies by antagonizing the tumor-progressive effects of epithelial-mesenchymal transition.

  9. Synthetic niches for differentiation of human embryonic stem cells bypassing embryoid body formation.

    Science.gov (United States)

    Liu, Yarong; Fox, Victoria; Lei, Yuning; Hu, Biliang; Joo, Kye-Il; Wang, Pin

    2014-07-01

    The unique self-renewal and pluripotency features of human embryonic stem cells (hESCs) offer the potential for unlimited development of novel cell therapies. Currently, hESCs are cultured and differentiated using methods, such as monolayer culture and embryoid body (EB) formation. As such, achieving efficient differentiation into higher order structures remains a challenge, as well as maintaining cell viability during differentiation into homogeneous cell populations. Here, we describe the application of highly porous polymer scaffolds as synthetic stem cell niches. Bypassing the EB formation step, these scaffolds are capable of three-dimensional culture of undifferentiated hESCs and subsequent directed differentiation into three primary germ layers. H9 hESCs were successfully maintained and proliferated in biodegradable polymer scaffolds based on poly (lactic-co-glycolic acid) (PLGA). The results showed that cells within PLGA scaffolds retained characteristics of undifferentiated pluripotent stem cells. Moreover, the scaffolds allowed differentiation towards the lineage of interest by the addition of growth factors to the culture system. The in vivo transplantation study revealed that the scaffolds could provide a microenvironment that enabled hESCs to interact with their surroundings, thereby promoting cell differentiation. Therefore, this approach, which provides a unique culture/differentiation system for hESCs, will find its utility in various stem cell-based tissue-engineering applications. © 2013 Wiley Periodicals, Inc.

  10. Autophagy is a critical regulator of memory CD8+ T cell formation

    Science.gov (United States)

    Puleston, Daniel J; Zhang, Hanlin; Powell, Timothy J; Lipina, Elina; Sims, Stuart; Panse, Isabel; Watson, Alexander S; Cerundolo, Vincenzo; Simon, Anna Katharina

    2014-01-01

    During infection, CD8+ T cells initially expand then contract, leaving a small memory pool providing long lasting immunity. While it has been described that CD8+ T cell memory formation becomes defective in old age, the cellular mechanism is largely unknown. Autophagy is a major cellular lysosomal degradation pathway of bulk material, and levels are known to fall with age. In this study, we describe a novel role for autophagy in CD8+ T cell memory formation. Mice lacking the autophagy gene Atg7 in T cells failed to establish CD8+ T cell memory to influenza and MCMV infection. Interestingly, autophagy levels were diminished in CD8+ T cells from aged mice. We could rejuvenate CD8+ T cell responses in elderly mice in an autophagy dependent manner using the compound spermidine. This study reveals a cell intrinsic explanation for poor CD8+ T cell memory in the elderly and potentially offers novel immune modulators to improve aged immunity. DOI: http://dx.doi.org/10.7554/eLife.03706.001 PMID:25385531

  11. Rhizobium nod factors reactivate the cell cycle during infection and nodule primordium formation, but the cycle is only completed in primordium formation.

    NARCIS (Netherlands)

    Yang, W.C.; Blank, de C.; Meskiene, I.; Hirt, H.; Bakker, J.; Kammen, van A.; Franssen, H.; Bisseling, T.

    1994-01-01

    Rhizobia induce the formation of root nodules on the roots of leguminous plants. In temperate legumes, nodule organogenesis starts with the induction of cell divisions in regions of the root inner cortex opposite protoxylem poles, resulting in the formation of nodule primordia. It has been

  12. Identification of undesirable white-colony-forming yeasts appeared on the surface of Japanese kimchi.

    Science.gov (United States)

    Suzuki, Ayaka; Muraoka, Naomi; Nakamura, Mariko; Yanagisawa, Yasuhira; Amachi, Seigo

    2018-02-01

    To identify yeasts involved in white-colony formation on Japanese commercial kimchi products, three types of kimchi were prepared and fermented at four different temperatures. At 4 °C, yeast colonies did not appear until 35 days, while more rapid white-colony formation occurred at higher temperatures (10, 15, and 25 °C). Combination of PCR-DGGE and direct isolation of yeasts from white colonies revealed that Kazachstania exigua and K. pseudohumilis were responsible for the white-colony formation. Inoculation of the isolated Kazachstania strains into fresh kimchi successfully reproduced white-colony formation at 15 °C but not at 4 °C. Growth experiments in liquid medium revealed that Kazachstania spp. grew fast at 15 °C even in the presence of acidulants, which are commonly added to Japanese kimchi products for prevention of yeast growth. These results suggest that white-colony formation on Japanese kimchi is caused by the genus Kazachstania, and that one of important factors determining white-colony formation is its fermentation temperature.

  13. ROCK is involved in vasculogenic mimicry formation in hepatocellular carcinoma cell line.

    Directory of Open Access Journals (Sweden)

    Ji-Gang Zhang

    Full Text Available Ras homolog family member A (RhoA and Rho-associated coiled coil-containing protein kinases 1 and 2 (ROCK1 and 2 are key regulators of focal adhesion, actomyosin contraction and cell motility. RhoA/ROCK signaling has emerged as an attractive target for the development of new cancer therapeutics. Whether RhoA/ROCK is involved in regulating the formation of tumor cell vasculogenic mimicry (VM is largely unknown. To confirm this hypothesis, we performed in vitro experiments using hepatocellular carcinoma (HCC cell lines. Firstly, we demonstrated that HCC cells with higher active RhoA/ROCK expression were prone to form VM channels, as compared with RhoA/ROCK low-expressing cells. Furthermore, Y27632 (a specific inhibitor of ROCK rather than exoenzyme C3 (a specific inhibitor of RhoA effectively inhibited the formation of tubular network structures in a dose-dependent manner. To elucidate the possible mechanism of ROCK on VM formation, real-time qPCR, western blot and immunofluorescence were used to detect changes of the key VM-related factors, including VE-cadherin, erythropoietin-producing hepatocellular carcinoma-A2 (EphA2, phosphoinositide 3-kinase (PI3K, matrix metalloproteinase (MMP14, MMP2, MMP9 and laminin 5γ2-chain (LAMC2, and epithelial-mesenchymal-transition (EMT markers: E-cadherin and Vimentin. The results showed that all the expression profiles were attenuated by blockage of ROCK. In addition, in vitro cell migration and invasion assays showed that Y27632 inhibited the migration and invasion capacity of HCC cell lines in a dose-dependent manner markedly. These data indicate that ROCK is an important mediator in the formation of tumor cell VM, and suggest that ROCK inhibition may prove useful in the treatment of VM in HCC.

  14. Teratoma formation of human embryonic stem cells in three-dimensional perfusion culture bioreactors.

    Science.gov (United States)

    Stachelscheid, H; Wulf-Goldenberg, A; Eckert, K; Jensen, J; Edsbagge, J; Björquist, P; Rivero, M; Strehl, R; Jozefczuk, J; Prigione, A; Adjaye, J; Urbaniak, T; Bussmann, P; Zeilinger, K; Gerlach, J C

    2013-09-01

    Teratoma formation in mice is today the most stringent test for pluripotency that is available for human pluripotent cells, as chimera formation and tetraploid complementation cannot be performed with human cells. The teratoma assay could also be applied for assessing the safety of human pluripotent cell-derived cell populations intended for therapeutic applications. In our study we examined the spontaneous differentiation behaviour of human embryonic stem cells (hESCs) in a perfused 3D multi-compartment bioreactor system and compared it with differentiation of hESCs and human induced pluripotent cells (hiPSCs) cultured in vitro as embryoid bodies and in vivo in an experimental mouse model of teratoma formation. Results from biochemical, histological/immunohistological and ultrastuctural analyses revealed that hESCs cultured in bioreactors formed tissue-like structures containing derivatives of all three germ layers. Comparison with embryoid bodies and the teratomas revealed a high degree of similarity of the tissues formed in the bioreactor to these in the teratomas at the histological as well as transcriptional level, as detected by comparative whole-genome RNA expression profiling. The 3D culture system represents a novel in vitro model that permits stable long-term cultivation, spontaneous multi-lineage differentiation and tissue formation of pluripotent cells that is comparable to in vivo differentiation. Such a model is of interest, e.g. for the development of novel cell differentiation strategies. In addition, the 3D in vitro model could be used for teratoma studies and pluripotency assays in a fully defined, controlled environment, alternatively to in vivo mouse models. Copyright © 2012 John Wiley & Sons, Ltd.

  15. Correlation of proliferative and clonogenic tumor cells in multiple myeloma

    International Nuclear Information System (INIS)

    Karp, J.E.; Burke, P.J.; Saylor, P.L.; Humphrey, R.L.

    1984-01-01

    To expand on the findings from previous clinical trials that the growth of residual tumor is increased at a predictable time following initial drug administration, malignant plasma cells from bone marrows of patients with multiple myeloma (MM) were examined for changes in proliferation and clonogenicity induced in vivo by cyclophosphamide and in vitro by drug-induced humoral stimulatory activity. Peak plasma cell [ 3 H]thymidine labeling index (LI) occurred predictably following drug and paralleled changes in agar colony formation by marrow cells obtained during therapy. Colony-forming capacity of pretreatment MM marrow populations was enhanced when those cells were cultured with humoral stimulatory activity, similar to the increased colony formation detected in Day 9 postcyclophosphamide marrows at the time of peak plasma cell LI. To further define a relationship between proliferative plasma cells and colony-forming tumor cells, MM marrows were fractionated by sedimentation on an isokinetic gradient. Enrichment of a proliferative tumor cell cohort was achieved, evidenced by [ 3 H]thymidine LI. Colony-forming cells were also enriched by isokinetic gradient sedimentation, and agar colony formation by MM marrow cell fractions correlated with the kinetic characteristics of the isolated subpopulations. These studies of whole and fractionated human MM marrow cell populations suggest that the kinetically active cells which are induced to proliferate in vivo and in vitro are closely related to the clonogenic tumor cells which produce colonies in agar and which, like those cells measured by [ 3 H]thymidine LI, respond to growth stimulation by drug-induced humoral stimulatory activity

  16. A flow cell for in situ synchrotron x-ray diffraction studies of scale formation under Bayer processing conditions

    Science.gov (United States)

    Webster, Nathan A. S.; Madsen, Ian C.; Loan, Melissa J.; Scarlett, Nicola V. Y.; Wallwork, Kia S.

    2009-08-01

    The design, construction, and commissioning of a stainless steel flow cell for in situ synchrotron x-ray diffraction studies of scale formation under Bayer processing conditions is described. The use of the cell is demonstrated by a study of Al(OH)3 scale formation on a mild steel substrate from synthetic Bayer liquor at 70 °C. The cell design allows for interchangeable parts and substrates and would be suitable for the study of scale formation in other industrial processes.

  17. Acyl Chain Preference in Foam Cell Formation from Mouse Peritoneal Macrophages.

    Science.gov (United States)

    Fujiwara, Yuko; Hama, Kotaro; Tsukahara, Makoto; Izumi-Tsuzuki, Ryosuke; Nagai, Toru; Ohe-Yamada, Mihoko; Inoue, Keizo; Yokoyama, Kazuaki

    2018-01-01

    Macrophage foam cells play critical roles in the initiation and development of atherosclerosis by synthesizing and accumulating cholesteryl ester (CE) in lipid droplets. However, in analyzing lipid metabolism in foam cell formation, studies have focused on the sterol group, and little research has been done on the acyl chains. Therefore, we adapted a model system using liposomes containing particular acyl chains and examined the effect of various acyl chains on foam cell formation. Of the phosphatidylserine (PS) liposomes tested containing PS, phosphatidylcholine, and cholesterol, we found that unsaturated (C18:1), but not saturated (C16:0 and C18:0), PS liposomes induced lipid droplet formation, indicating that foam cell formation depends on the nature of the acyl chain of the PS liposomes. Experiments on the uptake and accumulation of cholesterol from liposomes by adding [ 14 C]cholesterol suggested that foam cell formation could be induced only when cholesterol was converted to CE in the case of C18:1 PS liposomes. Both microscopic observations and metabolic analysis suggest that cholesterol incorporated into either C16:0 or C18:0 PS liposomes may stay intact after being taken in by endosomes. The [ 14 C]C18:1 fatty acyl chain in the C18:1 PS liposome was used to synthesize CE and triacylglycerol (TG). Interestingly, the [ 14 C]C16:0 in the C18:1 PS liposome was metabolized to sphingomyelin rather than being incorporated into either CE or TG, which could be because of enzymatic acyl chain selectivity. In conclusion, our results indicate that the acyl chain preference of macrophages could have some impact on their progression to foam cells.

  18. Color-coded Live Imaging of Heterokaryon Formation and Nuclear Fusion of Hybridizing Cancer Cells.

    Science.gov (United States)

    Suetsugu, Atsushi; Matsumoto, Takuro; Hasegawa, Kosuke; Nakamura, Miki; Kunisada, Takahiro; Shimizu, Masahito; Saji, Shigetoyo; Moriwaki, Hisataka; Bouvet, Michael; Hoffman, Robert M

    2016-08-01

    Fusion of cancer cells has been studied for over half a century. However, the steps involved after initial fusion between cells, such as heterokaryon formation and nuclear fusion, have been difficult to observe in real time. In order to be able to visualize these steps, we have established cancer-cell sublines from the human HT-1080 fibrosarcoma, one expressing green fluorescent protein (GFP) linked to histone H2B in the nucleus and a red fluorescent protein (RFP) in the cytoplasm and the other subline expressing RFP in the nucleus (mCherry) linked to histone H2B and GFP in the cytoplasm. The two reciprocal color-coded sublines of HT-1080 cells were fused using the Sendai virus. The fused cells were cultured on plastic and observed using an Olympus FV1000 confocal microscope. Multi-nucleate (heterokaryotic) cancer cells, in addition to hybrid cancer cells with single-or multiple-fused nuclei, including fused mitotic nuclei, were observed among the fused cells. Heterokaryons with red, green, orange and yellow nuclei were observed by confocal imaging, even in single hybrid cells. The orange and yellow nuclei indicate nuclear fusion. Red and green nuclei remained unfused. Cell fusion with heterokaryon formation and subsequent nuclear fusion resulting in hybridization may be an important natural phenomenon between cancer cells that may make them more malignant. The ability to image the complex processes following cell fusion using reciprocal color-coded cancer cells will allow greater understanding of the genetic basis of malignancy. Copyright© 2016 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

  19. [Effect of ferulic acid on cholesterol efflux in macrophage foam cell formation and potential mechanism].

    Science.gov (United States)

    Chen, Fu-xin; Wang, Lian-kai

    2015-02-01

    The formation of macrophage-derived foam cells is a typical feature of atherosclerosis (AS). Reverse cholesterol efflux (RCT) is one of important factors for the formation of macrophage foam cells. In this study, macrophage form cells were induced by oxidized low density lipoprotein (ox-LDL) and then treated with different concentrations of ferulic acid, so as to observe the effect of ferulic acid on the intracellular lipid metabolism in the ox-LDL-induced macrophage foam cell formation, the cholesterol efflux and the mRNA expression and protein levels of ATP binding cassette transporter A1 (ABCA1) and ATP binding cassette transporter G1 (ABCG1) that mediate cholesterol efflux, and discuss the potential mechanism of ferulic acid in resisting AS. According to the findings, compared with the control group, the ox-LDL-treated group showed significant increase in intracellular lipid content, especially for the cholesterol content; whereas the intracellular lipid accumulation markedly decreased, after the treatment with ferulic acid. The data also demonstrated that the mRNA and protein expressions of ABCA1 and ABCG1 significantly increased after macrophage foam cells were treated with different concentrations of ferulic acid. In summary, ferulic acid may show the anti-atherosclerosis effect by increasing the surface ABCA1 and ABCG1 expressions of macrophage form cells and promoting cholesterol efflux.

  20. Fluid-phase pinocytosis of native low density lipoprotein promotes murine M-CSF differentiated macrophage foam cell formation.

    Directory of Open Access Journals (Sweden)

    Manoj K Barthwal

    Full Text Available During atherosclerosis, low-density lipoprotein (LDL-derived cholesterol accumulates in macrophages to form foam cells. Macrophage uptake of LDL promotes foam cell formation but the mechanism mediating this process is not clear. The present study investigates the mechanism of LDL uptake for macrophage colony-stimulating factor (M-CSF-differentiated murine bone marrow-derived macrophages. LDL receptor-null (LDLR-/- macrophages incubated with LDL showed non-saturable accumulation of cholesterol that did not down-regulate for the 24 h examined. Incubation of LDLR-/- macrophages with increasing concentrations of (125I-LDL showed non-saturable macrophage LDL uptake. A 20-fold excess of unlabeled LDL had no effect on (125I-LDL uptake by wild-type macrophages and genetic deletion of the macrophage scavenger receptors CD36 and SRA did not affect (125I-LDL uptake, showing that LDL uptake occurred by fluid-phase pinocytosis independently of receptors. Cholesterol accumulation was inhibited approximately 50% in wild-type and LDLR-/- mice treated with LY294002 or wortmannin, inhibitors of all classes of phosphoinositide 3-kinases (PI3K. Time-lapse, phase-contrast microscopy showed that macropinocytosis, an important fluid-phase uptake pathway in macrophages, was blocked almost completely by PI3K inhibition with wortmannin. Pharmacological inhibition of the class I PI3K isoforms alpha, beta, gamma or delta did not affect macrophage LDL-derived cholesterol accumulation or macropinocytosis. Furthermore, macrophages from mice expressing kinase-dead class I PI3K beta, gamma or delta isoforms showed no decrease in cholesterol accumulation or macropinocytosis when compared with wild-type macrophages. Thus, non-class I PI3K isoforms mediated macropinocytosis in these macrophages. Further characterization of the components necessary for LDL uptake, cholesterol accumulation, and macropinocytosis identified dynamin, microtubules, actin, and vacuolar type H(+-ATPase as

  1. Fluid-Phase Pinocytosis of Native Low Density Lipoprotein Promotes Murine M-CSF Differentiated Macrophage Foam Cell Formation

    Science.gov (United States)

    Xu, Qing; Bohnacker, Thomas; Wymann, Matthias P.; Kruth, Howard S.

    2013-01-01

    During atherosclerosis, low-density lipoprotein (LDL)-derived cholesterol accumulates in macrophages to form foam cells. Macrophage uptake of LDL promotes foam cell formation but the mechanism mediating this process is not clear. The present study investigates the mechanism of LDL uptake for macrophage colony-stimulating factor (M-CSF)-differentiated murine bone marrow-derived macrophages. LDL receptor-null (LDLR−/−) macrophages incubated with LDL showed non-saturable accumulation of cholesterol that did not down-regulate for the 24 h examined. Incubation of LDLR−/− macrophages with increasing concentrations of 125I-LDL showed non-saturable macrophage LDL uptake. A 20-fold excess of unlabeled LDL had no effect on 125I-LDL uptake by wild-type macrophages and genetic deletion of the macrophage scavenger receptors CD36 and SRA did not affect 125I-LDL uptake, showing that LDL uptake occurred by fluid-phase pinocytosis independently of receptors. Cholesterol accumulation was inhibited approximately 50% in wild-type and LDLR−/− mice treated with LY294002 or wortmannin, inhibitors of all classes of phosphoinositide 3-kinases (PI3K). Time-lapse, phase-contrast microscopy showed that macropinocytosis, an important fluid-phase uptake pathway in macrophages, was blocked almost completely by PI3K inhibition with wortmannin. Pharmacological inhibition of the class I PI3K isoforms alpha, beta, gamma or delta did not affect macrophage LDL-derived cholesterol accumulation or macropinocytosis. Furthermore, macrophages from mice expressing kinase-dead class I PI3K beta, gamma or delta isoforms showed no decrease in cholesterol accumulation or macropinocytosis when compared with wild-type macrophages. Thus, non-class I PI3K isoforms mediated macropinocytosis in these macrophages. Further characterization of the components necessary for LDL uptake, cholesterol accumulation, and macropinocytosis identified dynamin, microtubules, actin, and vacuolar type H(+)-ATPase as

  2. Platelet-derived growth factor BB enhances osteoclast formation and osteoclast precursor cell chemotaxis.

    Science.gov (United States)

    Li, Dian-Qi; Wan, Qi-Long; Pathak, Janak L; Li, Zu-Bing

    2017-07-01

    Enhanced osteoclast formation increases bone resorption, which triggers bone remodeling. Platelet-derived growth factor BB (PDGF-BB) enhances precursor cell homing, angiogenesis, and bone healing, and thereby could also treat osteoporosis. However, the effect of PDGF-BB on osteoclast formation is not fully understood. We investigated whether exogenous recombinant PDGF-BB directly affects osteoclast formation and osteoclast precursor cell chemotaxis. The murine monocyte-macrophage cell line RAW264.7 and bone-marrow-derived macrophages were cultured with recombinant mouse PDGF-BB with or without a platelet-derived growth factor receptor β inhibitor (AG-1295) or a Janus kinase 2 inhibitor (AG-490) to analyze the effect on osteoclastogenesis in vitro. PDGF-BB with or without AG-490 or AG-1295 was locally administrated in the mandibular fracture of 16-week-old Sprague Dawley rats (n = 18) for 1-2 weeks to analyze the effect on osteoclastogenesis in vivo. The effect of the treatments on osteoclast formation, osteoclast precursor cell migration, and expression of osteoclastogenic signaling molecules was analyzed. PDGF-BB enhanced osteoclast formation both in vitro and in vivo, but AG-490 and AG-1295 inhibited this effect. PDGF-BB enhanced phosphorylation of extracellular-signal-regulated kinase 1/2 (ERK1/2), Akt, and signal transducer and activator of transcription 3 (STAT3) in RAW264.7 cells. AG-490 inhibited PDGF-BB-induced STAT3 phosphorylation. PDGF-BB enhanced RAW264.7 cell migration and gene expression of osteoclastogenic signaling molecules (i.e., nuclear factor of activated T cells 1, dendrocyte-expressed seven transmembrane protein, and B-cell lymphoma 2), and treatment with AG-1295, AG-490, or S3I-201 (a STAT3 inhibitor) reduced this effect. PDGF-BB enhanced osteoclast formation, osteoclast precursor cell chemotaxis, and phosphorylation of STAT3, Akt, and ERK1/2. but AG-1295 and AG-490 reduced this effect. These findings reflect the complexity of

  3. Stories, skulls, and colonial collections.

    Science.gov (United States)

    Roque, Ricardo

    2011-01-01

    The essay explores the hypothesis of colonial collecting processes involving the active addition of the colonial context and historical past to museum objects through the production of short stories. It examines the emergent historicity of collections through a focus on the "histories" that museum workers and colonial agents have been attaching to scientific collections of human skulls. Drawing on the notions of collection trajectory and historiographical work, it offers an alternative perspective from which to approach the creation of singular histories and individual archives for objects in collections.

  4. Genetic diversity affects colony survivorship in commercial honey bee colonies

    Science.gov (United States)

    Tarpy, David R.; vanEngelsdorp, Dennis; Pettis, Jeffrey S.

    2013-08-01

    Honey bee ( Apis mellifera) queens mate with unusually high numbers of males (average of approximately 12 drones), although there is much variation among queens. One main consequence of such extreme polyandry is an increased diversity of worker genotypes within a colony, which has been shown empirically to confer significant adaptive advantages that result in higher colony productivity and survival. Moreover, honey bees are the primary insect pollinators used in modern commercial production agriculture, and their populations have been in decline worldwide. Here, we compare the mating frequencies of queens, and therefore, intracolony genetic diversity, in three commercial beekeeping operations to determine how they correlate with various measures of colony health and productivity, particularly the likelihood of queen supersedure and colony survival in functional, intensively managed beehives. We found the average effective paternity frequency ( m e ) of this population of honey bee queens to be 13.6 ± 6.76, which was not significantly different between colonies that superseded their queen and those that did not. However, colonies that were less genetically diverse (headed by queens with m e ≤ 7.0) were 2.86 times more likely to die by the end of the study when compared to colonies that were more genetically diverse (headed by queens with m e > 7.0). The stark contrast in colony survival based on increased genetic diversity suggests that there are important tangible benefits of increased queen mating number in managed honey bees, although the exact mechanism(s) that govern these benefits have not been fully elucidated.

  5. Formate production through carbon dioxide hydrogenation with recombinant whole cell biocatalysts.

    Science.gov (United States)

    Alissandratos, Apostolos; Kim, Hye-Kyung; Easton, Christopher J

    2014-07-01

    The biological conversion of CO2 and H2 into formate offers a sustainable route to a valuable commodity chemical through CO2 fixation, and a chemical form of hydrogen fuel storage. Here we report the first example of CO2 hydrogenation utilising engineered whole-cell biocatalysts. Escherichia coli JM109(DE3) cells transformed for overexpression of either native formate dehydrogenase (FDH), the FDH from Clostridium carboxidivorans, or genes from Pyrococcus furiosus and Methanobacterium thermoformicicum predicted to express FDH based on their similarity to known FDH genes were all able to produce levels of formate well above the background, when presented with H2 and CO2, the latter in the form of bicarbonate. In the case of the FDH from P. furiosus the yield was highest, reaching more than 1 g L(-1)h(-1) when a hydrogen-sparging reactor design was used. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Inkjet formation of unilamellar lipid vesicles for cell-like encapsulation.

    Science.gov (United States)

    Stachowiak, Jeanne C; Richmond, David L; Li, Thomas H; Brochard-Wyart, Françoise; Fletcher, Daniel A

    2009-07-21

    Encapsulation of macromolecules within lipid vesicles has the potential to drive biological discovery and enable development of novel, cell-like therapeutics and sensors. However, rapid and reliable production of large numbers of unilamellar vesicles loaded with unrestricted and precisely-controlled contents requires new technologies that overcome size, uniformity, and throughput limitations of existing approaches. Here we present a high-throughput microfluidic method for vesicle formation and encapsulation using an inkjet printer at rates up to 200 Hz. We show how multiple high-frequency pulses of the inkjet's piezoelectric actuator create a microfluidic jet that deforms a bilayer lipid membrane, controlling formation of individual vesicles. Variations in pulse number, pulse voltage, and solution viscosity are used to control the vesicle size. As a first step toward cell-like reconstitution using this method, we encapsulate the cytoskeletal protein actin and use co-encapsulated microspheres to track its polymerization into a densely entangled cytoskeletal network upon vesicle formation.

  7. Macrophage-specific inhibition of NF-κB activation reduces foam-cell formation

    NARCIS (Netherlands)

    Ferreira, V.; Dijk, K.W. van; Groen, A.K.; Vos, R.M.; Kaa, J. van der; Gijbels, M.J.J.; Havekes, L.M.; Pannekoek, H.

    2007-01-01

    Accumulation of lipid-laden macrophages is a hallmark of atherosclerosis. The relevance of the key transcription factor nuclear factor κB (NF-κB) for macrophage-derived foam-cell formation has not been unequivocally resolved. Transgenic mice lines were generated in which NF-κB activation is

  8. A compact BrFAFC (bio-reformed formic acid fuel cell) converting formate to power.

    Science.gov (United States)

    Shin, Jong-Hwan; Jung, Namgee; Yoo, Sung Jong; Cho, Yong-Hun; Sung, Yung-Eun; Park, Tai Hyun

    2011-04-07

    A compact BrFAFC can directly convert formate to power without hydrogen storage and poisoning effect by CO at mild temperature. We are the first to establish the performance of the BrFAFC with high power density. Furthermore, this BrFAFC can be manufactured in a simple design for use in portable fuel cells.

  9. Free Energies of Formation Measurements on Solid-State Electrochemical Cells

    Science.gov (United States)

    Rollino, J. A.; Aronson, S.

    1972-01-01

    A simple experiment is proposed that can provide the student with some insight into the chemical properties of solids. It also demonstrates the relationship between the Gibbs free energy of formation of an ionic solid and the emf of an electrochemical cell. (DF)

  10. HDAC6 deacetylase activity is required for hypoxia-induced invadopodia formation and cell invasion.

    Directory of Open Access Journals (Sweden)

    Dominique Arsenault

    Full Text Available Despite significant progress in the cancer field, tumor cell invasion and metastasis remain a major clinical challenge. Cell invasion across tissue boundaries depends largely on extracellular matrix degradation, which can be initiated by formation of actin-rich cell structures specialized in matrix degradation called invadopodia. Although the hypoxic microenvironment within solid tumors has been increasingly recognized as an important driver of local invasion and metastasis, little is known about how hypoxia influences invadopodia biogenesis. Here, we show that histone deacetylase 6 (HDAC6, a cytoplasmic member of the histone deacetylase family, is a novel modulator of hypoxia-induced invadopodia formation. Hypoxia was found to enhance HDAC6 tubulin deacetylase activity through activation of the EGFR pathway. Activated HDAC6, in turn, triggered Smad3 phosphorylation resulting in nuclear accumulation. Inhibition of HDAC6 activity or knockdown of the protein inhibited both hypoxia-induced Smad3 activation and invadopodia formation. Our data provide evidence that hypoxia influences invadopodia formation in a biphasic manner, which involves the activation of HDAC6 deacetylase activity by EGFR, resulting in enhanced Smad phosphorylation and nuclear accumulation. The identification of HDAC6 as a key participant of hypoxia-induced cell invasion may have important therapeutic implications for the treatment of metastasis in cancer patients.

  11. Formation of hydrogen peroxide and nitric oxide in rat skeletal muscle cells during contractions

    DEFF Research Database (Denmark)

    Silveira, Leonardo R.; Pereira-Da-Silva, Lucia; Juel, Carsten

    2003-01-01

    We examined intra- and extracellular H(2)O(2) and NO formation during contractions in primary rat skeletal muscle cell culture. The fluorescent probes DCFH-DA/DCFH (2,7-dichlorofluorescein-diacetate/2,7-dichlorofluorescein) and DAF-2-DA/DAF-2 (4,5-diaminofluorescein-diacetate/4,5-diaminofluoresce...

  12. Development of Large-Format Lithium-Ion Cells with Silicon Anode and Low Flammable Electrolyte

    Science.gov (United States)

    Wu, James J.; Hernandez-Lugo, D. M.; Smart, M. C.; Ratnakumar, B. V.; Miller, T. B.; Lvovich, V. F.; Lytle, J. K.

    2014-01-01

    NASA is developing safe, high energy and high capacity lithium-ion cell designs and batteries for future missions under NASAs Advanced Space Power System (ASPS) project. Advanced cell components, such as high specific capacity silicon anodes and low-flammable electrolytes have been developed for improving the cell specific energy and enhancing safety. To advance the technology readiness level, we have developed large-format flight-type hermetically sealed battery cells by incorporating high capacity silicon anodes, commercially available lithium nickel, cobalt, aluminum oxide (NCA) cathodes, and low-flammable electrolytes. In this report, we will present the performance results of these various battery cells. In addition, we will also discuss the post-test cell analysis results as well.

  13. Influence of acellular natural lung matrix on murine embryonic stem cell differentiation and tissue formation.

    Science.gov (United States)

    Cortiella, Joaquin; Niles, Jean; Cantu, Andrea; Brettler, Andrea; Pham, Anthony; Vargas, Gracie; Winston, Sean; Wang, Jennifer; Walls, Shannon; Nichols, Joan E

    2010-08-01

    We report here the first attempt to produce and use whole acellular (AC) lung as a matrix to support development of engineered lung tissue from murine embryonic stem cells (mESCs). We compared the influence of AC lung, Gelfoam, Matrigel, and a collagen I hydrogel matrix on the mESC attachment, differentiation, and subsequent formation of complex tissue. We found that AC lung allowed for better retention of cells with more differentiation of mESCs into epithelial and endothelial lineages. In constructs produced on whole AC lung, we saw indications of organization of differentiating ESC into three-dimensional structures reminiscent of complex tissues. We also saw expression of thyroid transcription factor-1, an immature lung epithelial cell marker; pro-surfactant protein C, a type II pneumocyte marker; PECAM-1/CD31, an endothelial cell marker; cytokeratin 18; alpha-actin, a smooth muscle marker; CD140a or platelet-derived growth factor receptor-alpha; and Clara cell protein 10. There was also evidence of site-specific differentiation in the trachea with the formation of sheets of cytokeratin-positive cells and Clara cell protein 10-expressing Clara cells. Our findings support the utility of AC lung as a matrix for engineering lung tissue and highlight the critical role played by matrix or scaffold-associated cues in guiding ESC differentiation toward lung-specific lineages.

  14. The enamel matrix derivative (Emdogain) enhances human tongue carcinoma cells gelatinase production, migration and metastasis formation.

    Science.gov (United States)

    Laaksonen, Matti; Suojanen, Juho; Nurmenniemi, Sini; Läärä, Esa; Sorsa, Timo; Salo, Tuula

    2008-08-01

    Enamel matrix derivative Emdogain (EMD) is widely used in periodontal treatment to regenerate lost connective tissue and to improve the attachment of the teeth. Gelatinases (MMP-2 and -9) have an essential role in the promotion and progression of oral cancer growth and metastasis formation. We studied the effects of EMD on human tongue squamous cell carcinoma (HSC-3) cells in vitro and in vivo. In vitro, EMD (100 microg/ml and 200 microg/ml) remarkably induced the MMP-2 and -9 production from HSC-3 cells analysed by zymography and enzyme-linked immunosorbent assay. EMD also slightly induced the MMP-2 and -9 production from benign human mucosal keratinocytes (HMK). Furthermore, EMD clearly induced the transmigration of HSC-3 cells but had no effect on the HMK migration in transwell assays. The in vitro wound closure of HSC-3 cells was notably accelerated by EMD, whereas it had only minor effect on the wound closure of HMKs. The migration of both cell lines was inhibited by a selective cyclic anti-gelatinolytic peptide CTT-2. EMD had no effect on HSC-3 cell proliferation or apoptosis and only a limited effect on cell attachment to various extracellular matrix components. The in vivo mice experiment revealed that EMD substantially induced HSC-3 xenograft metastasis formation. Our results suggest that the use of EMD for patients with oral mucosal carcinomas or premalignant lesions should be carefully considered, possibly avoided.

  15. Mechanisms of DNA damage repair in adult stem cells and implications for cancer formation.

    Science.gov (United States)

    Weeden, Clare E; Asselin-Labat, Marie-Liesse

    2018-01-01

    Maintenance of genomic integrity in tissue-specific stem cells is critical for tissue homeostasis and the prevention of deleterious diseases such as cancer. Stem cells are subject to DNA damage induced by endogenous replication mishaps or exposure to exogenous agents. The type of DNA lesion and the cell cycle stage will invoke different DNA repair mechanisms depending on the intrinsic DNA repair machinery of a cell. Inappropriate DNA repair in stem cells can lead to cell death, or to the formation and accumulation of genetic alterations that can be transmitted to daughter cells and so is linked to cancer formation. DNA mutational signatures that are associated with DNA repair deficiencies or exposure to carcinogenic agents have been described in cancer. Here we review the most recent findings on DNA repair pathways activated in epithelial tissue stem and progenitor cells and their implications for cancer mutational signatures. We discuss how deep knowledge of early molecular events leading to carcinogenesis provides insights into DNA repair mechanisms operating in tumours and how these could be exploited therapeutically. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Volumetric Analysis of 3-D-Cultured Colonies in Wet Alginate Spots Using 384-Pillar Plate.

    Science.gov (United States)

    Lee, Dong Woo; Choi, Yea-Jun; Lee, Sang-Yun; Kim, Myoung-Hee; Doh, Il; Ryu, Gyu Ha; Choi, Soo-Mi

    2017-10-01

    The volumetric analysis of three-dimensional (3-D)-cultured colonies in alginate spots has been proposed to increase drug efficacy. In a previously developed pillar/well chip platform, colonies within spots are usually stained and dried for analysis of cell viability using two-dimensional (2-D) fluorescent images. Since the number of viable cells in colonies is directly related to colony volume, we proposed the 3-D analysis of colonies for high-accuracy cell viability calculation. The spots were immersed in buffer, and the 3-D volume of each colony was calculated from the 2-D stacking fluorescent images of the spot with different focal positions. In the experiments with human gastric carcinoma cells and anticancer drugs, we compared cell viability values calculated using the 2-D area and 3-D volume of colonies in the wet and dried alginate spots, respectively. The IC 50 value calculated using the 3-D volume of the colonies (9.5 μM) was less than that calculated in the 2-D area analysis (121.5 μM). We observed that the colony showed a more sensitive drug response regarding volume calculated from the 3-D image reconstructed using several confocal images than regarding colony area calculated in the 2-D analysis.

  17. TCPs, WUSs, and WINDs: Families of transcription factors that regulate shoot meristem formation, stem cell maintenance, and somatic cell differentiation

    Directory of Open Access Journals (Sweden)

    Miho eIkeda

    2014-09-01

    Full Text Available In contrast to somatic mammalian cells, which cannot alter their fate, plant cells can dedifferentiate to form totipotent callus cells and regenerate a whole plant, following treatment with specific phytohormones. However, the regulatory mechanisms and key factors that control differentiation-dedifferentiation and cell totipotency have not been completely clarified in plants. Recently, several plant transcription factors that regulate meristem formation and dedifferentiation have been identified and include members of the TEOSINTE BRANCHED1/CYCLOIDEA/PROLIFERATING CELL FACTOR (TCP, WUSCHEL (WUS, and WOUND INDUCED DEDIFFERENTIATION (WIND1 families. WUS and WIND positively control plant cell totipotency, while TCP negatively controls it. Interestingly, TCP is a transcriptional activator that acts as a negative regulator of shoot meristem formation, and WUS is a transcriptional repressor that positively maintains totipotency of the stem cells of the shoot meristem. We describe here the functions of TCP, WUS and WIND transcription factors in the regulation of differentiation-dedifferentiation by positive and negative transcriptional regulators.

  18. Matrix metalloproteinase-14 mediates formation of bile ducts and hepatic maturation of fetal hepatic progenitor cells

    Energy Technology Data Exchange (ETDEWEB)

    Otani, Satoshi [Department of Gastroenterology and Hepatology, Tokyo Medical and Dental University, Tokyo (Japan); Kakinuma, Sei, E-mail: skakinuma.gast@tmd.ac.jp [Department of Gastroenterology and Hepatology, Tokyo Medical and Dental University, Tokyo (Japan); Department for Liver Disease Control, Tokyo Medical and Dental University, Tokyo (Japan); Kamiya, Akihide [Institute of Innovative Science and Technology, Tokai University, Isehara (Japan); Goto, Fumio; Kaneko, Shun; Miyoshi, Masato; Tsunoda, Tomoyuki; Asano, Yu; Kawai-Kitahata, Fukiko; Nitta, Sayuri; Nakata, Toru; Okamoto, Ryuichi; Itsui, Yasuhiro; Nakagawa, Mina; Azuma, Seishin [Department of Gastroenterology and Hepatology, Tokyo Medical and Dental University, Tokyo (Japan); Asahina, Yasuhiro [Department of Gastroenterology and Hepatology, Tokyo Medical and Dental University, Tokyo (Japan); Department for Liver Disease Control, Tokyo Medical and Dental University, Tokyo (Japan); Yamaguchi, Tomoyuki [Division of Stem Cell Therapy, Institute of Medical Science, The University of Tokyo, Tokyo (Japan); Koshikawa, Naohiko [Division of Cancer Cell Research, Institute of Medical Science, The University of Tokyo, Tokyo (Japan); Seiki, Motoharu [Medical School, Kanazawa University, Kanazawa (Japan); Nakauchi, Hiromitsu [Division of Stem Cell Therapy, Institute of Medical Science, The University of Tokyo, Tokyo (Japan); and others

    2016-01-22

    Fetal hepatic stem/progenitor cells, called hepatoblasts, play central roles in liver development; however, the molecular mechanisms regulating the phenotype of these cells have not been completely elucidated. Matrix metalloproteinase (MMP)-14 is a type I transmembrane proteinase regulating pericellular proteolysis of the extracellular matrix and is essential for the activation of several MMPs and cytokines. However, the physiological functions of MMP-14 in liver development are unknown. Here we describe a functional role for MMP-14 in hepatic and biliary differentiation of mouse hepatoblasts. MMP-14 was upregulated in cells around the portal vein in perinatal stage liver. Formation of bile duct-like structures in MMP-14–deficient livers was significantly delayed compared with wild-type livers in vivo. In vitro biliary differentiation assays showed that formation of cholangiocytic cysts derived from MMP-14–deficient hepatoblasts was completely impaired, and that overexpression of MMP-14 in hepatoblasts promoted the formation of bile duct-like cysts. In contrast, the expression of molecules associated with metabolic functions in hepatocytes, including hepatic nuclear factor 4α and tryptophan 2,3-dioxygenase, were significantly increased in MMP-14–deficient livers. Expression of the epidermal growth factor receptor and phosphorylation of mitogen-activated protein kinases were significantly upregulated in MMP-14–deficient livers. We demonstrate that MMP-14–mediated signaling in fetal hepatic progenitor cells promotes biliary luminal formation around the portal vein and negatively controls the maturation of hepatocytes. - Highlights: • Loss of MMP-14 delayed formation of bile duct-like structures in perinatal liver. • Overexpression of MMP-14 in hepatobalsts promoted the biliary formation in vitro. • Loss of MMP-14 promoted hepatocyte maturation of hepatoblasts in vivo. • MMP-14–mediated signaling regulates terminal differentiation of

  19. Mutations in alpha- and beta-tubulin affect spindle formation in Chinese hamster ovary cells.

    Science.gov (United States)

    Abraham, I; Marcus, M; Cabral, F; Gottesman, M M

    1983-10-01

    Two Chinese hamster ovary cell lines with mutated beta-tubulins (Grs-2 and Cmd-4) and one that has a mutation in alpha-tubulin (Tax-1) are temperature sensitive for growth at 40.5 degrees C. To determine the functional defect in these mutant cells at the nonpermissive temperature, they were characterized with respect to cell cycle parameters and microtubule organization and function after relatively short periods at 40.5 degrees C. At the nonpermissive temperature all the mutants had normal appearing cytoplasmic microtubules. Premature chromosome condensation analysis failed to show any discrete step in the interphase cell cycle in which these mutants are arrested. These cells, however, show several defects at the nonpermissive temperature that appear related to the function of microtubules during mitosis. Time-lapse studies showed that mitosis was lengthened in the three mutant lines at 40.5 degrees C as compared with the wild-type cells at this temperature, resulting in a higher proportion of cells in mitosis after temperature shift. There was also a large increase in multinucleated cells in mutant populations after incubation at the nonpermissive temperature. Immunofluorescent studies using a monoclonal anti--alpha-tubulin antibody showed that the mutant cells had a high proportion of abnormal spindles at the nonpermissive temperature. The two altered beta-tubulins and the altered alpha-tubulin all were found to cause a similar phenotype at the high temperature that results in mitotic delay, defective cytokinesis, multinucleation, and ultimately, cell death. We conclude that spindle formation is the limiting microtubule function in these mutant cell lines at the nonpermissive temperature and that these cell lines will be of value for the study of the precise role of tubulin in mammalian spindle formation.

  20. Retinoic acid-treated pluripotent stem cells undergoing neurogenesis present increased aneuploidy and micronuclei formation.

    Directory of Open Access Journals (Sweden)

    Rafaela C Sartore

    Full Text Available The existence of loss and gain of chromosomes, known as aneuploidy, has been previously described within the central nervous system. During development, at least one-third of neural progenitor cells (NPCs are aneuploid. Notably, aneuploid NPCs may survive and functionally integrate into the mature neural circuitry. Given the unanswered significance of this phenomenon, we tested the hypothesis that neural differentiation induced by all-trans retinoic acid (RA in pluripotent stem cells is accompanied by increased levels of aneuploidy, as previously described for cortical NPCs in vivo. In this work we used embryonal carcinoma (EC cells, embryonic stem (ES cells and induced pluripotent stem (iPS cells undergoing differentiation into NPCs. Ploidy analysis revealed a 2-fold increase in the rate of aneuploidy, with the prevalence of chromosome loss in RA primed stem cells when compared to naïve cells. In an attempt to understand the basis of neurogenic aneuploidy, micronuclei formation and survivin expression was assessed in pluripotent stem cells exposed to RA. RA increased micronuclei occurrence by almost 2-fold while decreased survivin expression by 50%, indicating possible mechanisms by which stem cells lose their chromosomes during neural differentiation. DNA fragmentation analysis demonstrated no increase in apoptosis on embryoid bodies treated with RA, indicating that cell death is not the mandatory fate of aneuploid NPCs derived from pluripotent cells. In order to exclude that the increase in aneuploidy was a spurious consequence of RA treatment, not related to neurogenesis, mouse embryonic fibroblasts were treated with RA under the same conditions and no alterations in chromosome gain or loss were observed. These findings indicate a correlation amongst neural differentiation, aneuploidy, micronuclei formation and survivin downregulation in pluripotent stem cells exposed to RA, providing evidence that somatically generated chromosomal

  1. Flightless I interacts with NMMIIA to promote cell extension formation, which enables collagen remodeling

    Science.gov (United States)

    Arora, Pamma D.; Wang, Yongqiang; Bresnick, Anne; Janmey, Paul A.; McCulloch, Christopher A.

    2015-01-01

    We examined the role of the actin-capping protein flightless I (FliI) in collagen remodeling by mouse fibroblasts. FliI-overexpressing cells exhibited reduced spreading on collagen but formed elongated protrusions that stained for myosin10 and fascin and penetrated pores of collagen-coated membranes. Inhibition of Cdc42 blocked formation of cell protrusions. In FliI-knockdown cells, transfection with constitutively active Cdc42 did not enable protrusion formation. FliI-overexpressing cells displayed increased uptake and degradation of exogenous collagen and strongly compacted collagen fibrils, which was blocked by blebbistatin. Mass spectrometry analysis of FliI immunoprecipitates showed that FliI associated with nonmuscle myosin IIA (NMMIIA), which was confirmed by immunoprecipitation. GFP-FliI colocalized with NMMIIA at cell protrusions. Purified FliI containing gelsolin-like domains (GLDs) 1–6 capped actin filaments efficiently, whereas FliI GLD 2–6 did not. Binding assays showed strong interaction of purified FliI protein (GLD 1–6) with the rod domain of NMMIIA (kD = 0.146 μM), whereas FliI GLD 2–6 showed lower binding affinity (kD = 0.8584 μM). Cells expressing FliI GLD 2–6 exhibited fewer cell extensions, did not colocalize with NMMIIA, and showed reduced collagen uptake compared with cells expressing FliI GLD 1–6. We conclude that FliI interacts with NMMIIA to promote cell extension formation, which enables collagen remodeling in fibroblasts. PMID:25877872

  2. Engineering the Oryza sativa cell wall with rice NAC transcription factors regulating secondary wall formation.

    Science.gov (United States)

    Yoshida, Kouki; Sakamoto, Shingo; Kawai, Tetsushi; Kobayashi, Yoshinori; Sato, Kazuhito; Ichinose, Yasunori; Yaoi, Katsuro; Akiyoshi-Endo, Miho; Sato, Hiroko; Takamizo, Tadashi; Ohme-Takagi, Masaru; Mitsuda, Nobutaka

    2013-01-01

    Plant tissues that require structural rigidity synthesize a thick, strong secondary cell wall of lignin, cellulose and hemicelluloses in a complicated bridged structure. Master regulators of secondary wall synthesis were identified in dicots, and orthologs of these regulators have been identified in monocots, but regulation of secondary cell wall formation in monocots has not been extensively studied. Here we demonstrate that the rice transcription factors SECONDARY WALL NAC DOMAIN PROTEINs (SWNs) can regulate secondary wall formation in rice (Oryza sativa) and are potentially useful for engineering the monocot cell wall. The OsSWN1 promoter is highly active in sclerenchymatous cells of the leaf blade and less active in xylem cells. By contrast, the OsSWN2 promoter is highly active in xylem cells and less active in sclerenchymatous cells. OsSWN2 splicing variants encode two proteins; the shorter protein (OsSWN2S) has very low transcriptional activation ability, but the longer protein (OsSWN2L) and OsSWN1 have strong transcriptional activation ability. In rice, expression of an OsSWN2S chimeric repressor, driven by the OsSWN2 promoter, resulted in stunted growth and para-wilting (leaf rolling and browning under normal water conditions) due to impaired vascular vessels. The same OsSWN2S chimeric repressor, driven by the OsSWN1 promoter, caused a reduction of cell wall thickening in sclerenchymatous cells, a drooping leaf phenotype, reduced lignin and xylose contents and increased digestibility as forage. These data suggest that OsSWNs regulate secondary wall formation in rice and manipulation of OsSWNs may enable improvements in monocotyledonous crops for forage or biofuel applications.

  3. Engineering the Oryza sativa cell wall with rice NAC transcription factors regulating secondary wall formation

    Directory of Open Access Journals (Sweden)

    Kouki eYoshida

    2013-10-01

    Full Text Available Plant tissues that require structural rigidity synthesize a thick, strong secondary cell wall of lignin, cellulose and hemicelluloses in a complicated bridged structure. Master regulators of secondary wall synthesis were identified in dicots, and orthologs of these regulators have been identified in monocots, but regulation of secondary cell wall formation in monocots has not been extensively studied. Here we demonstrate that the rice transcription factors SECONDARY WALL NAC DOMAIN PROTEINs (SWNs can regulate secondary wall formation in rice (Oryza sativa and are potentially useful for engineering the monocot cell wall. The OsSWN1 promoter is highly active in sclerenchymatous cells of the leaf blade and less active in xylem cells. By contrast, the OsSWN2 promoter is highly active in xylem cells and less active in sclerenchymatous cells. OsSWN2 splicing variants encode two proteins; the shorter protein (OsSWN2S has very low transcriptional activation ability, but the longer protein (OsSWN2L and OsSWN1 have strong transcriptional activation ability. In rice, expression of an OsSWN2S chimeric repressor, driven by the OsSWN2 promoter, resulted in stunted growth and para-wilting (leaf rolling and browning under normal water conditions due to impaired vascular vessels. The same OsSWN2S chimeric repressor, driven by the OsSWN1 promoter, caused a reduction of cell wall thickening in sclerenchymatous cells, a drooping leaf phenotype, reduced lignin and xylose contents and increased digestibility as forage. These data suggest that OsSWNs regulate secondary wall formation in rice and manipulation of OsSWNs may enable improvements in monocotyledonous crops for forage or biofuel applications.

  4. Formation of Nanoscale Bioimprints of Muscle Cells Using UV-Cured Spin-Coated Polymers

    Directory of Open Access Journals (Sweden)

    Fahmi Samsuri

    2009-01-01

    Full Text Available We report a nanoscale replication method suitable for biological specimens that has potential in single cell studies and in formation of 3D biocompatible scaffolds. Earlier studies using a heat-curable polydimethylsiloxane (PDMS or a UV-curable elastomer introduced Bioimprint replication to facilitate cell imaging. However, the replicating conditions for thermal polymerization are known to cause cell dehydration during curing. In this study, a UV-cured methacrylate copolymer was developed for use in creating replicas of living cells and was tested on rat muscle cells. Bioimprints of muscle cells were formed by spin coating under UV irradiation. The polymer replicas were then separated from the muscle cells and were analyzed under an Atomic Force Microscope (AFM, in tapping mode, because it has low tip-sample forces and thus will not destroy the fine structures of the imprint. The new polymer is biocompatible with higher replication resolution and has a faster curing process than other types of silicon-based organic polymers such as PDMS. High resolution images of the muscle cell imprints showed the micro-and nanostructures of the muscle cells, including cellular fibers and structures within the cell membranes. The AFM is able to image features at nanoscale resolution with the potential for recognizing abnormalities on cell membranes at early stages of disease progression.

  5. Increased mobilization and yield of stem cells using plerixafor in combination with granulocyte-colony stimulating factor for the treatment of non-Hodgkin’s lymphoma and multiple myeloma

    Directory of Open Access Journals (Sweden)

    Louis M Pelus

    2011-02-01

    Full Text Available Louis M Pelus1, Sherif S Farag21Department of Microbiology and Immunology, 2Division of Hematology and Oncology, Department of Internal Medicine, Indiana University School of Medicine, Indianapolis, IndianaAbstract: Multiple myeloma and non-Hodgkin’s lymphoma remain the most common indications for high-dose chemotherapy and autologous peripheral blood stem cell rescue. While a CD34+ cell dose of 1 × 106/kg is considered the minimum required for engraftment, higher CD34+ doses correlate with improved outcome. Numerous studies, however, support targeting a minimum CD34+ cell dose of 2.0 × 106/kg, and an “optimal” dose of 4 to 6 × 106/kg for a single transplant. Unfortunately, up to 40% of patients fail to mobilize an optimal CD34+ cell dose using myeloid growth factors alone. Plerixafor is a novel reversible inhibitor of CXCR4 that significantly increases the mobilization and collection of higher numbers of hematopoietic progenitor cells. Two randomized multi-center clinical trials in patients with non-Hodgkin’s lymphoma and multiple myeloma have demonstrated that the addition of plerixafor to granulocyte-colony stimulating factor increases the mobilization and yield of CD34+ cells in fewer apheresis days, which results in durable engraftment. This review summarizes the pharmacology and evidence for the clinical efficacy of plerixafor in mobilizing hematopoietic stem and progenitor cells, and discusses potential ways to utilize plerixafor in a cost-effective manner in patients with these diseases.Keywords: plerixafor, mobilization, stem cells, lymphoma, myeloma

  6. Selective ablation of the androgen receptor in mouse sertoli cells affects sertoli cell maturation, barrier formation and cytoskeletal development.

    Directory of Open Access Journals (Sweden)

    Ariane Willems

    2010-11-01

    Full Text Available The observation that mice with a selective ablation of the androgen receptor (AR in Sertoli cells (SC (SCARKO mice display a complete block in meiosis supports the contention that SC play a pivotal role in the control of germ cell development by androgens. To delineate the physiological and molecular mechanism responsible for this control, we compared tubular development in pubertal SCARKO mice and littermate controls. Particular attention was paid to differences in SC maturation, SC barrier formation and cytoskeletal organization and to the molecular mediators potentially involved. Functional analysis of SC barrier development by hypertonic perfusion and lanthanum permeation techniques and immunohistochemical analysis of junction formation showed that SCARKO mice still attempt to produce a barrier separating basal and adluminal compartment but that barrier formation is delayed and defective. Defective barrier formation was accompanied by disturbances in SC nuclear maturation (immature shape, absence of prominent, tripartite nucleoli and SC polarization (aberrant positioning of SC nuclei and cytoskeletal elements such as vimentin. Quantitative RT-PCR was used to study the transcript levels of genes potentially related to the described phenomena between day 8 and 35. Differences in the expression of SC genes known to play a role in junction formation could be shown from day 8 for Cldn11, from day 15 for Cldn3 and Espn, from day 20 for Cdh2 and Jam3 and from day 35 for ZO-1. Marked differences were also noted in the transcript levels of several genes that are also related to cell adhesion and cytoskeletal dynamics but that have not yet been studied in SC (Actn3, Ank3, Anxa9, Scin, Emb, Mpzl2. It is concluded that absence of a functional AR in SC impedes the remodeling of testicular tubules expected at the onset of spermatogenesis and interferes with the creation of the specific environment needed for germ cell development.

  7. Hydroxide Self-Feeding High-Temperature Alkaline Direct Formate Fuel Cells.

    Science.gov (United States)

    Li, Yinshi; Sun, Xianda; Feng, Ying

    2017-05-22

    Conventionally, both the thermal degradation of the anion-exchange membrane and the requirement of additional hydroxide for fuel oxidation reaction hinder the development of the high-temperature alkaline direct liquid fuel cells. The present work addresses these two issues by reporting a polybenzimidazole-membrane-based direct formate fuel cell (DFFC). Theoretically, the cell voltage of the high-temperature alkaline DFFC can be as high as 1.45 V at 90 °C. It has been demonstrated that a proof-of-concept alkaline DFFC without adding additional hydroxide yields a peak power density of 20.9 mW cm -2 , an order of magnitude higher than both alkaline direct ethanol fuel cells and alkaline direct methanol fuel cells, mainly because the hydrolysis of formate provides enough OH - ions for formate oxidation reaction. It was also found that this hydroxide self-feeding high-temperature alkaline DFFC shows a stable 100 min constant-current discharge at 90 °C, proving the conceptual feasibility. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Contribution of Cell Elongation to the Biofilm Formation of Pseudomonas aeruginosa during Anaerobic Respiration

    Science.gov (United States)

    Park, Yongjin; Yoon, Sang Sun

    2011-01-01

    Pseudomonas aeruginosa, a gram-negative bacterium of clinical importance, forms more robust biofilm during anaerobic respiration, a mode of growth presumed to occur in abnormally thickened mucus layer lining the cystic fibrosis (CF) patient airway. However, molecular basis behind this anaerobiosis-triggered robust biofilm formation is not clearly defined yet. Here, we identified a morphological change naturally accompanied by anaerobic respiration in P. aeruginosa and investigated its effect on the biofilm formation in vitro. A standard laboratory strain, PAO1 was highly elongated during anaerobic respiration compared with bacteria grown aerobically. Microscopic analysis demonstrated that cell elongation likely occurred as a consequence of defective cell division. Cell elongation was dependent on the presence of nitrite reductase (NIR) that reduces nitrite (NO2 −) to nitric oxide (NO) and was repressed in PAO1 in the presence of carboxy-PTIO, a NO antagonist, demonstrating that cell elongation involves a process to respond to NO, a spontaneous byproduct of the anaerobic respiration. Importantly, the non-elongated NIR-deficient mutant failed to form biofilm, while a mutant of nitrate reductase (NAR) and wild type PAO1, both of which were highly elongated, formed robust biofilm. Taken together, our data reveal a role of previously undescribed cell biological event in P. aeruginosa biofilm formation and suggest NIR as a key player involved in such process. PMID:21267455

  9. Hypoxia enhances proliferation and tissue formation of human mesenchymal stem cells

    International Nuclear Information System (INIS)

    Grayson, Warren L.; Zhao, Feng; Bunnell, Bruce; Ma, Teng

    2007-01-01

    Changes in oxygen concentrations affect many of the innate characteristics of stem and progenitor cells. Human mesenchymal stem cells (hMSCs) were maintained under hypoxic atmospheres (2% O 2 ) for up to seven in vitro passages. This resulted in approximately 30-fold higher hMSC expansion over 6 weeks without loss of multi-lineage differentiation capabilities. Under hypoxia, hMSCs maintained their growth-rates even after reaching confluence, resulting in the formation of multiple cell layers. Hypoxic hMSCs also displayed differences in the cell and nuclear morphologies as well as enhanced ECM formation and organization. These changes in cellular characteristics were accompanied by higher mRNA levels of Oct-4 and HIF-2α, as well as increased expression levels of connexin-43, a protein used in gap junction formation. The results from this study demonstrated that oxygen concentrations affected many aspects of stem-cell physiology, including growth and in vitro development, and may be a critical parameter during expansion and differentiation

  10. Formation of Deposits on the Cathode Surface of Aluminum Electrolysis Cells

    Science.gov (United States)

    Allard, François; Soucy, Gervais; Rivoaland, Loig

    2014-12-01

    The efficiency of electrolysis cells for aluminum production is reduced when deposits are formed on the cathode block surface. Overfeeding of alumina or excessive heat loss in industrial cells leads to the formation of highly resistive deposits. In this study, the chemical composition of sludge, ledge toe, and thin deposits was investigated at the bottom of both industrial and experimental electrolysis cells. The formation of deposits in laboratory experiments was demonstrated in acidic, neutral, and basic electrolytic bath. A gradient of chiolite (Na5Al3F14) and α-Al2O3 was observed in the deposits. The bath at the bottom of the experimental electrolysis cell had a higher cryolite ratio implying a higher liquidus temperature. The sludge formed at the bottom of the cell can lift the aluminum metal resulting in an important reduction of the contact surface between the aluminum and the cathode block. Moreover, the deposits disturb the current path and generate horizontal current components in the metal which enhance the motion and lower the current efficiency. A thin film of bath supersaturated in alumina was observed under the metal. This work provides clarification on the formation mechanisms of the various deposits responsible for the deterioration of the cathode surface.

  11. The Future Lunar Flora Colony

    Science.gov (United States)

    Goel, E. G.; Guven, U. G.

    2017-10-01

    A constructional design for the primary establishment for a lunar colony using the micrometeorite rich soil is proposed. It highlights the potential of lunar regolith combined with Earth technology for water and oxygen for human outposts on the Moon.

  12. Recent Honey Bee Colony Declines

    National Research Council Canada - National Science Library

    Johnson, Renee

    2007-01-01

    ...). Current reports indicate that beekeepers in 35 states have been affected. Recent surveys indicate that about one-half of surveyed beekeepers have experienced "abnormal" or "severe" colony losses...

  13. Women's Education in Colonial America

    Science.gov (United States)

    Long, Huey B.

    1975-01-01

    Exploring the contribution of the home, apprenticeship, and evening schools, the analysis suggests that while sex bias apparently favored males in quality and quantity of educational opportunity, women's education in Colonial America was richer than popularly conceived. (Author/MW)

  14. DAZL Expression Explains Origin and Central Formation of Primordial Germ Cells in Chickens.

    Science.gov (United States)

    Lee, Hyung Chul; Choi, Hee Jung; Lee, Hyo Gun; Lim, Jeong Mook; Ono, Tamao; Han, Jae Yong

    2016-01-01

    The timing and biological events associated with germ cell specification in chickens have not been determined yet. In this study, we report the origin of primordial germ cells (PGCs) and germ plasm dynamics through investigation of the expression of the chicken homolog of deleted in azoospermia-like (cDAZL) gene during germ cell specification. Asymmetric localization of germ plasm in the center of oocytes from preovulatory follicle stages leads to PGCs being formed in the center. During cleavage stages, DAZL expression pattern changes from a subcellular localization to a diffuse form before and after zygotic genome activation. Meanwhile, PGCs exhibit transcriptional active status during their specification. In addition, knockdown studies of cDAZL, which result in reduced proliferation, aberrant gene expression profiles, and PGC apoptosis in vitro, suggest its possible roles for PGC formation in chicken. In conclusion, DAZL expression reveals formation and initial positioning of PGCs in chickens.

  15. Comparison of autologous cell therapy and granulocyte-colony stimulating factor (G-CSF) injection vs. G-CSF injection alone for the treatment of acute radiation syndrome in a non-human primate model

    International Nuclear Information System (INIS)

    Bertho, Jean-Marc; Frick, Johanna; Prat, Marie; Demarquay, Christelle; Dudoignon, Nicolas; Trompier, Francois; Gorin, Norbert-Claude; Thierry, Dominique; Gourmelon, Patrick

    2005-01-01

    Purpose: To compare the efficacy of autologous cell therapy after irradiation combined with granulocyte-colony stimulating factor (G-CSF) injections with G-CSF treatment alone in a heterogeneous model of irradiation representative of an accidental situation. Material and Methods: Non-human primates were irradiated at 8.7 Gy whole-body dose with the right arm shielded to receive 4.8 Gy. The first group of animals received G-CSF (lenograstim) injections starting 6 h after irradiation, and a second group received a combination of G-CSF (lenograstim) injections and autologous expanded hematopoietic cells. Animals were followed up for blood cell counts, circulating progenitors, and bone marrow cellularity. Results: No significant differences were seen between the two treatment groups, whatever the parameter observed: time to leukocyte or platelet recovery and duration and severity of aplasia. Conclusion: Our results indicated that identical recovery kinetic was observed when irradiated animals are treated with G-CSF independently of the reinjection of ex vivo expanded autologous hematopoietic cells. Thus G-CSF injections might be chosen as a first-line therapeutic strategy in the treatment of accidental acute radiation victims

  16. New role for granulocyte colony-stimulating factor-induced extracellular signal-regulated kinase 1/2 in histone modification and retinoic acid receptor α recruitment to gene promoters: relevance to acute promyelocytic leukemia cell differentiation.

    Science.gov (United States)

    Cassinat, B; Zassadowski, F; Ferry, C; Llopis, L; Bruck, N; Lainey, E; Duong, V; Cras, A; Despouy, G; Chourbagi, O; Beinse, G; Fenaux, P; Rochette Egly, C; Chomienne, C

    2011-04-01

    The induction of the granulocytic differentiation of leukemic cells by all-trans retinoic acid (RA) has been a major breakthrough in terms of survival for acute promyelocytic leukemia (APL) patients. Here we highlight the synergism and the underlying novel mechanism between RA and the granulocyte colony-stimulating factor (G-CSF) to restore differentiation of RA-refractory APL blasts. First, we show that in RA-refractory APL cells (UF-1 cell line), PML-RA receptor alpha (RARα) is not released from target promoters in response to RA, resulting in the maintenance of chromatin repression. Consequently, RARα cannot be recruited, and the RA target genes are not activated. We then deciphered how the combination of G-CSF and RA successfully restored the activation of RA target genes to levels achieved in RA-sensitive APL cells. We demonstrate that G-CSF restores RARα recruitment to target gene promoters through the activation of the extracellular signal-regulated kinase (ERK)/mitogen-activated protein kinase (MAPK) pathway and the subsequent derepression of chromatin. Thus, combinatorial activation of cytokines and RARs potentiates transcriptional activity through epigenetic modifications induced by specific signaling pathways.

  17. Colony collapse disorder in Europe.

    Science.gov (United States)

    Dainat, Benjamin; Vanengelsdorp, Dennis; Neumann, Peter

    2012-02-01

    Colony collapse disorder (CCD) is a condition of honey bees, which has contributed in part to the recent major losses of honey bee colonies in the USA. Here we report the first CCD case from outside of the USA. We suggest that more standardization is needed for the case definition to diagnose CCD and to compare data on a global scale. © 2011 Society for Applied Microbiology and Blackwell Publishing Ltd.

  18. Macrophage Liver Kinase B1 Inhibits Foam Cell Formation and Atherosclerosis.

    Science.gov (United States)

    Liu, Zhaoyu; Zhu, Huaiping; Dai, Xiaoyan; Wang, Cheng; Ding, Ye; Song, Ping; Zou, Ming-Hui

    2017-10-13

    LKB1 (liver kinase B1) is a serine/threonine kinase and tumor suppressor, which regulates the homeostasis of hematopoietic cells and immune responses. Macrophages transform into foam cells upon taking-in lipids. No role for LKB1 in foam cell formation has previously been reported. We sought to establish the role of LKB1 in atherosclerotic foam cell formation. LKB1 expression was examined in human carotid atherosclerotic plaques and in western diet-fed atherosclerosis-prone Ldlr -/- and ApoE -/- mice. LKB1 expression was markedly reduced in human plaques when compared with nonatherosclerotic vessels. Consistently, time-dependent reduction of LKB1 levels occurred in atherosclerotic lesions in western diet-fed Ldlr -/- and ApoE -/- mice. Exposure of macrophages to oxidized low-density lipoprotein downregulated LKB1 in vitro. Furthermore, LKB1 deficiency in macrophages significantly increased the expression of SRA (scavenger receptor A), modified low-density lipoprotein uptake and foam cell formation, all of which were abolished by blocking SRA. Further, we found LKB1 phosphorylates SRA resulting in its lysosome degradation. To further investigate the role of macrophage LKB1 in vivo, ApoE -/- LKB1 fl/fl LysM cre and ApoE -/- LKB1 fl/fl mice were fed with western diet for 16 weeks. Compared with ApoE -/- LKB1 fl/fl wild-type control, ApoE -/- LKB1 fl/fl LysM cre mice developed more atherosclerotic lesions in whole aorta and aortic root area, with markedly increased SRA expression in aortic root lesions. We conclude that macrophage LKB1 reduction caused by oxidized low-density lipoprotein promotes foam cell formation and the progression of atherosclerosis. © 2017 American Heart Association, Inc.

  19. Trypanosoma cruzi: Entry Into Mammalian Host Cells and Parasitophorous Vacuole Formation

    Directory of Open Access Journals (Sweden)

    Emile Santos Barrias

    2013-08-01

    Full Text Available Trypanosoma cruzi, the causative agent of Chagas disease, is transmitted to vertebrate hosts by blood-sucking insects. This protozoan is an obligate intracellular parasite. The infective forms of the parasite are the metacyclic trypomastigotes, amastigotes and bloodstream trypomastigotes. The recognition between the parasite and mammalian host cell, involves numerous molecules present in both cell types, and similar to several intracellular pathogens, T.cruzi is internalized by host cells via multiple endocytic pathways. Morphological studies demonstrated that after the interaction of the infective forms of T.cruzi with phagocytic or non-phagocytic cell types, plasma membrane protrusions can form, showing similarity with those observed during canonical phagocytosis or macropinocytic events. Additionally, several molecules known to be molecular markers of membrane rafts, macropinocytosis and phagocytosis have been demonstrated to be present at the invasion site. These events may or may not depend on the host cell lysosomes and cytoskeleton. In addition, after penetration, components of the host endosomal-lysosomal system, such as early endosomes, late endosomes and lysosomes, participate in the formation of the nascent parasithophorous vacuole (VP. Dynamin, a molecule involved in vesicle formation, has been shown to be involved in the parasitophorous vacuole release from the host cell plasma membrane. This review focuses on the multiple pathways that T.cruzi can use to enter the host cells until complete VP formation. We will describe different endocytic processes, such as phagocytosis, macropinocytosis, endocytosis using membrane microdomains and clathrin-dependent endocytosis and show results that are consistent with their use by this smart parasite. We will also discuss other mechanisms that have been described, such as active penetration and the process that takes advantage of cell membrane wound repair.

  20. Mic13 Is Essential for Formation of Crista Junctions in Mammalian Cells.

    Science.gov (United States)

    Anand, Ruchika; Strecker, Valentina; Urbach, Jennifer; Wittig, Ilka; Reichert, Andreas S

    2016-01-01

    Mitochondrial cristae are connected to the inner boundary membrane via crista junctions which are implicated in the regulation of oxidative phosphorylation, apoptosis, and import of lipids and proteins. The MICOS complex determines formation of crista junctions. We performed complexome profiling and identified Mic13, also termed Qil1, as a subunit of the MICOS complex. We show that MIC13 is an inner membrane protein physically interacting with MIC60, a central subunit of the MICOS complex. Using the CRISPR/Cas method we generated the first cell line deleted for MIC13. These knockout cells show a complete loss of crista junctions demonstrating that MIC13 is strictly required for the formation of crista junctions. MIC13 is required for the assembly of MIC10, MIC26, and MIC27 into the MICOS complex. However, it is not needed for the formation of the MIC60/MIC19/MIC25 subcomplex suggesting that the latter is not sufficient for crista junction formation. MIC13 is also dispensable for assembly of respiratory chain complexes and for maintaining mitochondrial network morphology. Still, lack of MIC13 resulted in a moderate reduction of mitochondrial respiration. In summary, we show that MIC13 has a fundamental role in crista junction formation and that assembly of respiratory chain supercomplexes is independent of mitochondrial cristae shape.

  1. Mic13 Is Essential for Formation of Crista Junctions in Mammalian Cells.

    Directory of Open Access Journals (Sweden)

    Ruchika Anand

    Full Text Available Mitochondrial cristae are connected to the inner boundary membrane via crista junctions which are implicated in the regulation of oxidative phosphorylation, apoptosis, and import of lipids and proteins. The MICOS complex determines formation of crista junctions. We performed complexome profiling and identified Mic13, also termed Qil1, as a subunit of the MICOS complex. We show that MIC13 is an inner membrane protein physically interacting with MIC60, a central subunit of the MICOS complex. Using the CRISPR/Cas method we generated the first cell line deleted for MIC13. These knockout cells show a complete loss of crista junctions demonstrating that MIC13 is strictly required for the formation of crista junctions. MIC13 is required for the assembly of MIC10, MIC26, and MIC27 into the MICOS complex. However, it is not needed for the formation of the MIC60/MIC19/MIC25 subcomplex suggesting that the latter is not sufficient for crista junction formation. MIC13 is also dispensable for assembly of respiratory chain complexes and for maintaining mitochondrial network morphology. Still, lack of MIC13 resulted in a moderate reduction of mitochondrial respiration. In summary, we show that MIC13 has a fundamental role in crista junction formation and that assembly of respiratory chain supercomplexes is independent of mitochondrial cristae shape.

  2. Somite-Derived Retinoic Acid Regulates Zebrafish Hematopoietic Stem Cell Formation.

    Directory of Open Access Journals (Sweden)

    Laura M Pillay

    Full Text Available Hematopoietic stem cells (HSCs are multipotent progenitors that generate all vertebrate adult blood lineages. Recent analyses have highlighted the importance of somite-derived signaling factors in regulating HSC specification and emergence from dorsal aorta hemogenic endothelium. However, these factors remain largely uncharacterized. We provide evidence that the vitamin A derivative retinoic acid (RA functions as an essential regulator of zebrafish HSC formation. Temporal analyses indicate that RA is required for HSC gene expression prior to dorsal aorta formation, at a time when the predominant RA synthesis enzyme, aldh1a2, is strongly expressed within the paraxial mesoderm and somites. Previous research implicated the Cxcl12 chemokine and Notch signaling pathways in HSC formation. Consequently, to understand how RA regulates HSC gene expression, we surveyed the expression of components of these pathways in RA-depleted zebrafish embryos. During somitogenesis, RA-depleted embryos exhibit altered expression of jam1a and jam2a, which potentiate Notch signaling within nascent endothelial cells. RA-depleted embryos also exhibit a severe reduction in the expression of cxcr4a, the predominant Cxcl12b receptor. Furthermore, pharmacological inhibitors of RA synthesis and Cxcr4 signaling act in concert to reduce HSC formation. Our analyses demonstrate that somite-derived RA functions to regulate components of the Notch and Cxcl12 chemokine signaling pathways during HSC formation.

  3. Golgi structure formation, function, and post-translational modifications in mammalian cells.

    Science.gov (United States)

    Huang, Shijiao; Wang, Yanzhuang

    2017-01-01

    The Golgi apparatus is a central membrane organelle for trafficking and post-translational modifications of proteins and lipids in cells. In mammalian cells, it is organized in the form of stacks of tightly aligned flattened cisternae, and dozens of stacks are often linked laterally into a ribbon-like structure located in the perinuclear region of the cell. Proper Golgi functionality requires an intact architecture, yet Golgi structure is dynamically regulated during the cell cycle and under disease conditions. In this review, we summarize our current understanding of the relationship between Golgi structure formation, function, and regulation, with focus on how post-translational modifications including phosphorylation and ubiquitination regulate Golgi structure and on how Golgi unstacking affects its functions, in particular, protein trafficking, glycosylation, and sorting in mammalian cells.

  4. Analysis of Giant-nucleated Cell Formation Following X-ray and Proton Irradiations

    Science.gov (United States)

    Almahwasi, Ashraf Abdu

    Radiation-induced genetic instability has been observed in survivors of irradiated cancerous and normal cells in vitro and in vivo and has been determined in different forms, such as delayed cell death, chromosomal aberration or mutation. A well defined and characterized normal human-diploid AG1522 fibroblast cell line was used to study giant-nucleated cell (GCs) formation as the ultimate endpoint of this research. The average nuclear cross-sectional areas of the AG1522 cells were measured in mum2. The doubling time required by the AG1522 cells to divide was measured. The potential toxicity of the Hoechst dye at a working concentration on the live AG1522 cells was assessed. The yield of giant cells was determined at 7, 14 and 21 days after exposure to equivalent clinical doses of 0.2, 1 or 2 Gy of X-ray or proton irradiation. Significant differences were found to exist between X-ray or proton irradiation when compared with sham-irradiated control populations. The frequency of GCs induced by X-rays was also compared to those formed in proton irradiated cultures. The results confirm that 1 Gy X-rays are shown to induce higher rates of mitotically arrested GCs, increasing continually over time up to 21 days post-irradiation. The yield of GCs was significantly greater (10%) compared to those formed in proton populations (2%) 21 days postirradiation. The GCs can undergo a prolonged mitotic arrest that significantly increases the length of cell cycle. The arrest of GCs at the mitotic phase for longer periods of time might be indicative of a strategy for cell survival, as it increases the time available for DNA repair and enables an alternative route to division for the cells. However, the reduction in their formation 21 days after both types of radiation might favour GCs formation, ultimately contributing to carcinogenesis or cancer therapy resistance. The X-ray experiments revealed a dose-dependent increase in the GCs up to 14 days after irradiation. Although the proton

  5. Fuels for fuel cells: Fuel and catalyst effects on carbon formation

    Energy Technology Data Exchange (ETDEWEB)

    Borup, R. L. (Rodney L.); Inbody, M. A. (Michael A.); Perry, W. L. (William Lee); Parkinson, W. J. (William Jerry),

    2002-01-01

    The goal of this research is to explore the effects of fuels, fuel constituents, additives and impurities on the performance of on-board hydrogen generation devices and consequently on the overall performance of fuel cell systems using reformed hydrocarbon fuels. Different fuels and components have been tested in automotive scale, adiabatic autothermal reactors to observe their relative reforming characteristics with various operating conditions. Carbon formation has been modeled and was experimentally monitored in situ during operation by laser measurements of the effluent reformate. Ammonia formation was monitored, and conditions varied to observe under what conditions N H 3 is made.

  6. Zinc oxide nanoparticles induce migration and adhesion of monocytes to endothelial cells and accelerate foam cell formation

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, Yuka; Tada-Oikawa, Saeko [Graduate School of Regional Innovation Studies, Mie University, Tsu (Japan); Ichihara, Gaku [Department of Occupational and Environmental Health, Nagoya University Graduate School of Medicine, Nagoya (Japan); Yabata, Masayuki; Izuoka, Kiyora [Graduate School of Regional Innovation Studies, Mie University, Tsu (Japan); Suzuki, Masako; Sakai, Kiyoshi [Nagoya City Public Health Research Institute, Nagoya (Japan); Ichihara, Sahoko, E-mail: saho@gene.mie-u.ac.jp [Graduate School of Regional Innovation Studies, Mie University, Tsu (Japan)

    2014-07-01

    Metal oxide nanoparticles are widely used in industry, cosmetics, and biomedicine. However, the effects of exposure to these nanoparticles on the cardiovascular system remain unknown. The present study investigated the effects of nanosized TiO{sub 2} and ZnO particles on the migration and adhesion of monocytes, which are essential processes in atherosclerogenesis, using an in vitro set-up of human umbilical vein endothelial cells (HUVECs) and human monocytic leukemia cells (THP-1). We also examined the effects of exposure to nanosized metal oxide particles on macrophage cholesterol uptake and foam cell formation. The 16-hour exposure to ZnO particles increased the level of monocyte chemotactic protein-1 (MCP-1) and induced the migration of THP-1 monocyte mediated by increased MCP-1. Exposure to ZnO particles also induced adhesion of THP-1 cells to HUVECs. Moreover, exposure to ZnO particles, but not TiO{sub 2} particles, upregulated the expression of membrane scavenger receptors of modified LDL and increased cholesterol uptake in THP-1 monocytes/macrophages. In the present study, we found that exposure to ZnO particles increased macrophage cholesterol uptake, which was mediated by an upregulation of membrane scavenger receptors of modified LDL. These results suggest that nanosized ZnO particles could potentially enhance atherosclerogenesis and accelerate foam cell formation. - Highlights: • Effects of metal oxide nanoparticles on foam cell formation were investigated. • Exposure to ZnO nanoparticles induced migration and adhesion of monocytes. • Exposure to ZnO nanoparticles increased macrophage cholesterol uptake. • Expression of membrane scavenger receptors of modified LDL was also increased. • These effects were not observed after exposure to TiO{sub 2} nanoparticles.

  7. The Effect of Xuefu Zhuyu Decoction (血府逐瘀汤) on in vitro Endothelial Progenitor Cell Tube Formation

    Science.gov (United States)

    Dong, Gao; Li-ya, Wu; Yu-huan, Jiao; Kaptchuk, Ted J; Wen-yuan, Chen; Yan, Chen; Bo, Lu; Jun, Song; Ke-ji, Chen

    2010-01-01

    Objective To observe the in vitro effect of Xuefu Zhuyu Decoction on endothelial progenitor cell (EPC) tube formation. Methods We prepared mononucleus cells from rat marrow by Ficoll density gradient centrifuge, separated EPCs by differential attachment method and observed, with inverted microscope, the effect of serum containing Xuefu Zhuyu Decoction (XFZYD) on endothelial progentor cell (EPC) tube formation. Results After 1 day, EPCs exposed to serum containing 5%, 10% and 15% XFZYD formed typical tube or vessel networks. Compared to the control group, the tube formation was 2 days ahead and most of the were smaller. Conclusion XFZYD could induce EPCs angiogenesis and hasten tube formation, especially capillary vessel. PMID:20131036

  8. Pretransplant mobilization with granulocyte colony-stimulating factor improves b-cell reconstitution by lentiviral vector gene therapy in SCID-X1 mice

    NARCIS (Netherlands)

    M.W. Huston (Marshall W.); A.R.A. Riegman (Adriaan R.A.); R.M.A. Yadak (Rana); Y.M. van Helsdingen (Yvette); H. De Boer (Helen); N.P. van Til (Niek); G. Wagemaker (Gerard)

    2014-01-01

    textabstractHematopoietic stem cell (HSC) gene therapy is a demonstrated effective treatment for X-linked severe combined immunodeficiency (SCID-X1), but B-cell reconstitution and function has been deficient in many of the gene therapy treated patients. Cytoreductive preconditioning is known to

  9. Bactericidal Antibiotics Promote Reactive Oxygen Species Formation and Inflammation in Human Sinonasal Epithelial Cells

    Science.gov (United States)

    Kohanski, Michael A; Tharakan, Anuj; Lane, Andrew P.; Ramanathan, Murugappan

    2015-01-01

    Background Bactericidal antibiotics have been shown to stimulate reactive oxygen species (ROS) formation in mammalian cells through mitochondrial dysfunction. This results in oxidative tissue damage that may have negative consequences for long-term antibiotic use. Antibiotics are widely and heavily used in the treatment of acute and chronic sinusitis, however the relationship between antibiotics and ROS formation in sinonasal epithelial cells (SNECs) has not yet been demonstrated. Methods Human SNECs were collected from patients during endoscopic sinus surgery and grown in culture at the air-liquid interface. Differentiated SNECs were stimulated with the bactericidal antibiotics amoxicillin and levofloxacin and the bacteriostatic antibiotic clarithromycin for 24-hours. Reactive oxygen species were quantified via fluorescence. Cell death was quantified by LDH secretion. Expression of inflammatory markers such as TNF-α and Nrf2 mediated antioxidant genes were measured by RT-PCR. Results Cultured SNECs treated with the bactericidal antibiotics amoxicillin and levofloxacin resulted in a significant increase in production of ROS (pbactericidal antibiotics leads to formation of ROS with an associated increase in inflammatory and antioxidant gene expression and cell death. This suggests that long term or inappropriate antibiotic use in the treatment of sinusitis, may result in oxidative tissue damage to the sinonasal epithelium. Future studies will explore the clinical implications of such damage to the sinonasal epithelium. PMID:26624249

  10. Formation of retinal direction-selective circuitry initiated by starburst amacrine cell homotypic contact.

    Science.gov (United States)

    Ray, Thomas A; Roy, Suva; Kozlowski, Christopher; Wang, Jingjing; Cafaro, Jon; Hulbert, Samuel W; Wright, Christopher V E; Field, Greg D; Kay, Jeremy N

    2018-04-03

    A common strategy by which developing neurons locate their synaptic partners is through projections to circuit-specific neuropil sublayers. Once established, sublayers serve as a substrate for selective synapse formation, but how sublayers arise during neurodevelopment remains unknown. Here we identify the earliest events that initiate formation of the direction-selective circuit in the inner plexiform layer of mouse retina. We demonstrate that radially-migrating newborn starburst amacrine cells establish homotypic contacts on arrival at the inner retina. These contacts, mediated by the cell-surface protein MEGF10, trigger neuropil innervation resulting in generation of two sublayers comprising starburst-cell dendrites. This dendritic scaffold then recruits projections from circuit partners. Abolishing MEGF10-mediated contacts profoundly delays and ultimately disrupts sublayer formation, leading to broader direction tuning and weaker direction-selectivity in retinal ganglion cells. Our findings reveal a mechanism by which differentiating neurons transition from migratory to mature morphology, and highlight this mechanism's importance in forming circuit-specific sublayers. © 2018, Ray et al.

  11. Energy efficiency of platinum-free alkaline direct formate fuel cells

    International Nuclear Information System (INIS)

    Wang, L.Q.; Bellini, M.; Filippi, J.; Folliero, M.; Lavacchi, A.; Innocenti, M.; Marchionni, A.; Miller, H.A.; Vizza, F.

    2016-01-01

    Highlights: • Alkaline Platinum-free formate fuel cells top 42% efficiency @ 60 °C. • Palladium efficiently oxidizes formate. • Power density exceeding 250 mW cm −2 @ 60 °C has been achieved. • Performance exceeds that of Alkaline Direct Alcohol Fuel Cell. - Abstract: We report the energy performance of a new platinum-free alkaline direct formate fuel cell, equipped with a commercial anion exchange membrane, a nanostructured Pd/C anode and a Fe–Co/C cathode. The cell was investigated both at room temperature and at 60 °C for the determination of the following parameters: (i) maximum power density, (ii) delivered energy, (iii) faradic (fuel conversion) and energy efficiency. These parameters show a dramatic dependence on fuel composition. The highest energy efficiency is obtained using high energy density fuel (4 M KCOOH and 4 M KOH) and with a maximum operating temperature of 60 °C. This represents a key step in the progress of alkaline platinum-free DFFC technology, demonstrating their potential as power sources for portable electronic devices and remote power generation systems. For example, a fuel load of 750 ml in a DFFC device operating at 60 °C would be able to produce 90 W h of energy, that required to fully charge the battery of a laptop computer.

  12. Primary Phenomenon in the Network Formation of Endothelial Cells: Effect of Charge.

    Science.gov (United States)

    Arai, Shunto

    2015-12-07

    Blood vessels are essential organs that are involved in the supply of nutrients and oxygen and play an important role in regulating the body's internal environment, including pH, body temperature, and water homeostasis. Many studies have examined the formation of networks of endothelial cells. The results of these studies have revealed that vascular endothelial growth factor (VEGF) affects the interactions of these cells and modulates the network structure. Though almost all previous simulation studies have assumed that the chemoattractant VEGF is present before network formation, vascular endothelial cells secrete VEGF only after the cells bind to the substrate. This suggests VEGF is not essential for vasculogenesis especially at the early stage. Using a simple experiment, we find chain-like structures which last quite longer than it is expected, unless the energetically stable cluster should be compact. Using a purely physical model and simulation, we find that the hydrodynamic interaction retard the compaction of clusters and that the chains are stabilized through the effects of charge. The charge at the surface of the cells affect the interparticle potential, and the resulting repulsive forces prevent the chains from folding. The ions surrounding the cells may also be involved in this process.

  13. Differentiation of mouse embryonic stem cells into endoderm without embryoid body formation.

    Directory of Open Access Journals (Sweden)

    Peter T W Kim

    Full Text Available Pluripotent embryonic stem cells hold a great promise as an unlimited source of tissue for treatment of chronic diseases such as Type 1 diabetes. Herein, we describe a protocol using all-trans-retinoic acid, basic fibroblast growth factor and dibutyryl cAMP (DBcAMP in the absence of embryoid body formation, for differentiation of murine embryonic stem cells into definitive endoderm that may serve as pancreatic precursors. The produced cells were analyzed by quantitative PCR, immunohistochemistry and static insulin release assay for markers of trilaminar embryo, and pancreas. Differentiated cells displayed increased Sox17 and Foxa2 expression consistent with definitive endoderm production. There was minimal production of Sox7, an extraembryonic endoderm marker, and Oct4, a marker of pluripotency. There was minimal mesoderm or neuroectoderm formation based on expression levels of the markers brachyury and Sox1, respectively. Various assays revealed that the cell clusters generated by this protocol express markers of the pancreatic lineage including insulin I, insulin II, C-peptide, PDX-1, carboxypeptidase E, pan-cytokeratin, amylase, glucagon, PAX6, Ngn3 and Nkx6.1. This protocol using all-trans-retinoic acid, DBcAMP, in the absence of embryoid bodies, generated cells that have features of definitive endoderm that may serve as pancreatic endocrine precursors.

  14. Blocking Wnt5a signaling decreases CD36 expression and foam cell formation in atherosclerosis.

    Science.gov (United States)

    Ackers, Ian; Szymanski, Candice; Duckett, K Jordan; Consitt, Leslie A; Silver, Mitchell J; Malgor, Ramiro

    2018-02-20

    Wnt5a is a highly studied member of the Wnt family and recently has been implicated in the pathogenesis of atherosclerosis, but its precise role is unknown. Foam cell development is a critical process to atherosclerotic plaque formation. In the present study, we investigated the role of noncanonical Wnt5a signaling in the development of foam cells. Human carotid atherosclerotic tissue and THP-1-derived macrophages were used to investigate the contribution of Wnt5a signaling in the formation of foam cells. Immunohistochemistry was used to evaluate protein expression of scavenger receptors and noncanonical Wnt5a receptors [frizzled 5 (Fz5) and receptor tyrosine kinase-like orphan receptor 2 (Ror2)] in human atherosclerotic macrophages/foam cells. Changes in protein expression in response to Wnt5a stimulation/inhibition were determined by Western blot, and lipid accumulation was evaluated by fluorescent lipid droplet staining. Wnt5a (Pfoam cells within the plaque. In vitro studies revealed that Wnt5a significantly increased the expression of the lipid uptake receptor CD36 (P.05). rWnt5a also significantly increased lipid accumulation in THP-1 macrophages (Pfoam cells. Copyright © 2018. Published by Elsevier Inc.

  15. Laticiferous canal formation in fruits of Decaisnea fargesii: a programmed cell death process?

    Science.gov (United States)

    Zhou, Ya-Fu; Liu, Wen-Zhe

    2011-10-01

    Programmed cell death (PCD), a topic of abiding interest, remodels plants at the cell, tissue, and organ levels involving various developmental processes of plants. The aim of this study is to provide a morphological characterization of evidence of PCD involvement in the laticiferous canal formation in fruit of Decaisnea fargesii. Several ultrastructural features of PCD have been observed including disintegration of vacuole and plasma membranes, cell wall degeneration, degenerated cytoplasm, abundant membrane structures and flocculent material, mitochondria and misshapen nuclei coupled with degraded plastids in vacuoles, and nuclei enveloped by rubber granule. In D. fargesii, the nuclei of the secretory epidermal cells become TUNEL-positive from the sunken stage to the late expanding stage, then DAPI-negative during the mature stage, indicating an early event of deoxyribonucleic acid (DNA) cleavage and a late event of complete DNA degeneration. Gel electrophoresis indicates that DNA cleavage is random and does not result in the laddering pattern indicating multiples of internucleosomal units. During the PCD of secretory epidermal cells, the rubber granules continue to be synthesized and accumulated in the secretory epidermal cells despite nuclear degradation. The PCD's role in laticiferous canal formation suggests that PCD may play important roles in gland development of plants.

  16. Serum amyloid A stimulates macrophage foam cell formation via lectin-like oxidized low-density lipoprotein receptor 1 upregulation

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Ha Young, E-mail: hayoung@skku.edu [Department of Biological Science, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Mitochondria Hub Regulation Center, Dong-A University, Busan 602-714 (Korea, Republic of); Kim, Sang Doo [Department of Biological Science, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Baek, Suk-Hwan [Department of Biochemistry and Molecular Biology, College of Medicine, Yeungnam University, Daegu 705-717 (Korea, Republic of); Choi, Joon Hyuk [Department of Pathology, College of Medicine, Yeungnam University, Daegu 705-717 (Korea, Republic of); Cho, Kyung-Hyun [School of Biotechnology, Yeungnam University, Gyeongsan 712-749 (Korea, Republic of); Zabel, Brian A. [Palo Alto Institute for Research and Education, Veterans Affairs Hospital, Palo Alto, CA 94304 (United States); Bae, Yoe-Sik, E-mail: yoesik@skku.edu [Department of Biological Science, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Mitochondria Hub Regulation Center, Dong-A University, Busan 602-714 (Korea, Republic of); Samsung Advanced Institute for Health Sciences and Technology, Sungkyunkwan University, Seoul 135-710 (Korea, Republic of)

    2013-03-29

    Highlights: ► SAA induced macrophage foam cell