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Sample records for factor limiting growth

  1. Rapid method of determining factors limiting bacterial growth in soil

    OpenAIRE

    Aldén Demoling, Louise; Demoling, Fredrik; Bååth, Erland

    2001-01-01

    A technique to determine which nutrients limit bacterial growth in soil was developed. The method was based on measuring the thymidine incorporation rate of bacteria after the addition of C, N, and P in different combinations to soil samples. First, the thymidine incorporation method was tested in two different soils: an agricultural soil and a forest humus soil. Carbon (as glucose) was found to be the limiting substance for bacterial growth in both of these soils. The effect of adding differ...

  2. Corn Response to Competition: Growth Alteration vs. Yield Limiting Factors

    Science.gov (United States)

    Understanding competition mechanisms among adjacent plants can improve site-specific management recommendations. This 2-yr study compared two hypotheses, yield limiting factors vs. behavior modification, to explain plant interactions. Corn was grown under different levels of stress by varying light ...

  3. Organizational growth of SMEs in Serbia: Governance as a built-in limiting growth factor

    OpenAIRE

    Janićijević Nebojša; Bogićević-Milikić Biljana

    2010-01-01

    The aim of the study is to investigate the characteristics of governance structures in three Serbian medium-sized enterprises and, particularly, whether the corporate governance influences organizational growth prospects of these firms. The results suggest that in all the companies owners held a tight personal control over all activities, not being willing to delegate any authority to professional managers. This unwillingness of owners to delegate authority actually presents the main barrier ...

  4. Therapeutic targeting of epidermal growth factor receptor in human cancer: successes and limitations%Therapeutic targeting of epidermal growth factor receptor in humancancer: successes and limitations

    Institute of Scientific and Technical Information of China (English)

    Jill Wykosky; Tim Fenton; Frank Furnari; Webster K. Cavenee

    2011-01-01

    Epidermal growth factor receptor (EGFR) is one of the most commonly altered genes in human cancer by way of over-expression, amplification, and mutation. Targeted inhibition of EGFR activity suppresses signal transduction pathways which control tumor cell growth, proliferation, and resistance to apoptosis. Small molecule tyrosine kinase inhibitors and monoclonal antibodies are among the most common EGFR-targeting agents and have been used clinically for treating various malignancies. This review discusses the successes and challenges of targeting EGFR in human cancer. The genetic alterations of EGFR tend to occur more often in some solid tumors than others, as do the mechanisms of resistance to targeted inhibition. The clinical and basic science experiences with these agents thus far have important implications for the future of therapeutic targeting of EGFR.

  5. Anatomy of a bottleneck: diagnosing factors limiting population growth in the Puerto Rican parrot

    Science.gov (United States)

    Beissenger, S.R.; Wunderle, J.M.; Meyers, J.M.; Saether, B.-E.; Engen, S.

    2008-01-01

    captive young into wild nests), diminishing the importance of nest failure as a limiting factor. Annual survival has been periodically reduced by catastrophes (hurricanes), which have greatly constrained population growth, but survival rates were high under non-catastrophic conditions. Although the importance of factors maintaining the Puerto Rican Parrot bottleneck varied throughout the 30-year period of study, we determined their long-term influence using LSA simulations to correlate variation in demographic rates with variation in population growth (k). The bottleneck appears to have been maintained primarily by periodic catastrophes (hurricanes) that reduced adult survival, and secondarily by environmental and/or behavioral factors that resulted in a failure of many adults to nest. The influence of inbreeding through reduced hatching success played a much less significant role, even when additional effects of inbreeding on the production and mortality of young were incorporated into the LSA. Management actions needed to speed recovery include (1) continued nest guarding to minimize the effects of nest failure due to nongenetic causes; (2) creating a second population at another location on the island --a process that was recently initiated--to reduce the chance that hurricane strikes will cause extinction; and (3) determining the causes of the low percentage of breeders in the population and ameliorating them, which would have a large impact on population growth.

  6. Limits to growth reconsidered.

    Science.gov (United States)

    Hagen, E E

    1972-01-01

    In their book, ''The Limits of Growth,'' the authors conclude that through pollution, exhaustion of natural resources, and limits to the food supply, the world faces a catastrophic fall in population and in living standards by the middle of the 21st century. The authors fail to state, however, 1 centrally important assumption underlying their results, but which is present through their omission of the contrary assumption. In their model the continuing technical progress that has been a primary feature of the material world for the past 200 years suddenly ceases. The assumptions of the model presented in ''Limits of Growth'' are not the assumptions other analysts make - these are strangely unrealistic. These assumptions require closer examination. The assumption concerning population assumes that the sole determinants of birthrates are the level of industrialization and the food supply. This is not good demography, for demographers have long recognized that it may have been the decrease in death rates, not industrialization or the rise in income, that caused the decrease in birthrates. Furthermore, their theory that many of the natural resources are irreplacable is like the belief that the sun revolves around the earth. It is obvious and false. It neglects that part of technical process which includes invention of new natural resources. Technical advance is needed and the following are some of the problems that technical advance must overcome: 1) a need to discover how to increase food production progressively while preventing the runoff of chemical fertilizers from the soil into waterways, 2) the ''natural'' minerals on which until recently all have depended are ''biodegradable,'' 3) there is a similar problem with radioactive nuclear wastes; 4) energy must dissipate into heat; and 5) there is a need to hasten the decline in birthrates throughout the world. In conclusion, indefinitely continuing growth is not regarded as desirable only as possible.

  7. FACTORS LIMITING BACTERIAL GROWTH : III. CELL SIZE AND "PHYSIOLOGIC YOUTH" IN BACTERIUM COLI CULTURES.

    Science.gov (United States)

    Hershey, A D; Bronfenbrenner, J

    1938-07-20

    1. Measurements of the rate of oxygen uptake per cell in transplants of Bacterium coli from cultures of this organism in different phases of growth have given results in essential agreement with the observations of others. 2. Correlations of viable count, centrifugable nitrogen, and turbidity, with oxygen consumption, indicate that the increased metabolism during the early portion of the growth period is quantitatively referable to increased average size of cells. 3. Indirect evidence has suggested that the initial rate of growth of transplants is not related to the phase of growth of the parent culture.

  8. Limited efficacy of COX-2 inhibitors on nerve growth factor and metalloproteinases expressions in human synovial fibroblasts.

    Science.gov (United States)

    Yorifuji, Makiko; Sawaji, Yasunobu; Endo, Kenji; Kosaka, Taiichi; Yamamoto, Kengo

    2016-05-01

    Nerve growth factor (NGF) is associated with arthritic pain and metalloproteinases are implicated in collagen and aggrecan degradation. Although selective COX-2 inhibitors are recommended for the treatment of arthritic diseases, their effects on NGF and metalloproteinases remain unclear. This study investigated the regulations of NGF and metalloproteinases by selective COX-2 inhibitors in isolated human synovial cells. The isolated human synovial cells were stimulated with IL-1β in the presence of selective COX-2 inhibitors (NS-398 or celecoxib) with or without exogenous PGE2 or its receptor (EP1-4) agonists. The expressions of NGF, MMP-1, -3, -13, ADAMTS-4, and -5 were quantified by real-time PCR and their proteins were determined by Western blotting. The amount of PGE2 released was measured by enzyme-linked immunosorbent assay (ELISA). The IL-1β inductions of NGF and MMP-1 and MMP-13 were augmented by the COX-2 inhibitors, whereas the inductions of ADAMTS-4 and ADAMTS-5 were inhibited. These actions were reversed by supplementing PGE2 or the EP4 agonist exogenously. Our comprehensive analysis revealed that COX-2 inhibitors may be beneficial for suppressing aggrecan degradation and for reducing inflammatory pain by inhibiting PGE2 release, although they may have limited efficacy in suppressing collagen degradation and nerve growth. This study suggests the feedback roles of PGE2 in the negative regulation of NGF and MMP-1 and MMP-13 and the positive regulation of ADAMTS-4 and ADAMTS-5. Copyright © 2016 The Japanese Orthopaedic Association. Published by Elsevier B.V. All rights reserved.

  9. Ethylene Response Factor6 acts as a central regulator of leaf growth under water-limiting conditions in Arabidopsis.

    Science.gov (United States)

    Dubois, Marieke; Skirycz, Aleksandra; Claeys, Hannes; Maleux, Katrien; Dhondt, Stijn; De Bodt, Stefanie; Vanden Bossche, Robin; De Milde, Liesbeth; Yoshizumi, Takeshi; Matsui, Minami; Inzé, Dirk

    2013-05-01

    Leaf growth is a complex developmental process that is continuously fine-tuned by the environment. Various abiotic stresses, including mild drought stress, have been shown to inhibit leaf growth in Arabidopsis (Arabidopsis thaliana), but the underlying mechanisms remain largely unknown. Here, we identify the redundant Arabidopsis transcription factors ETHYLENE RESPONSE FACTOR5 (ERF5) and ERF6 as master regulators that adapt leaf growth to environmental changes. ERF5 and ERF6 gene expression is induced very rapidly and specifically in actively growing leaves after sudden exposure to osmotic stress that mimics mild drought. Subsequently, enhanced ERF6 expression inhibits cell proliferation and leaf growth by a process involving gibberellin and DELLA signaling. Using an ERF6-inducible overexpression line, we demonstrate that the gibberellin-degrading enzyme GIBBERELLIN 2-OXIDASE6 is transcriptionally induced by ERF6 and that, consequently, DELLA proteins are stabilized. As a result, ERF6 gain-of-function lines are dwarfed and hypersensitive to osmotic stress, while the growth of erf5erf6 loss-of-function mutants is less affected by stress. Besides its role in plant growth under stress, ERF6 also activates the expression of a plethora of osmotic stress-responsive genes, including the well-known stress tolerance genes STZ, MYB51, and WRKY33. Interestingly, activation of the stress tolerance genes by ERF6 occurs independently from the ERF6-mediated growth inhibition. Together, these data fit into a leaf growth regulatory model in which ERF5 and ERF6 form a missing link between the previously observed stress-induced 1-aminocyclopropane-1-carboxylic acid accumulation and DELLA-mediated cell cycle exit and execute a dual role by regulating both stress tolerance and growth inhibition.

  10. Limits to the growth debate

    Energy Technology Data Exchange (ETDEWEB)

    Gordon, L.

    The first two major studies sponsored by the club of Rome were the report of the Meadows team at MIT, The Limits to Growth, published in 1972, and the Mesarovic and Pestel report, Mankind at the Turning Point, published in 1974. When the Club of Rome met in Philadelphia in April of 1976, its pronouncements reflected a frame of mind quite different from that of 1972. Recently, Herman Kahn and his colleagues at the Hudson Institute have published The Next 200 Years, a book evidently inspired as much by antagonism to the limits-to-growth school of thought as by affirmative faith in its own vision of technological optimism. The author discusses the content of the studies and summarizes his own position in four areas. (1) While no trend of growth of anything can continue indefinitely in the real world, there are not global physical limits to economic growth within a time frame susceptible to plausible foresight or relevant to policy making. (2) In some world regions, notably South Asia and tropical Africa, population growth rates do indeed threaten to create a kind of Malthusian trap, and the rapid reduction of fertility is critically important to their development prospects and urgent in time. (3) For other parts of the world, both rates and directions of growth will be more influenced by changes in preferences for consumption and in attitudes toward production than by physical constraints, although higher energy costs and environmental pressures will also be important influences in generating such changes in growth patterns. (4) Probable changes in directions of growth will generate new and important issues in international economic and political relations, with both dangers and opportunities for the evolving world order. (MCW)

  11. From Limits to Growth to Limitless Growth

    Directory of Open Access Journals (Sweden)

    Garry Jacobs

    2012-04-01

    Full Text Available The publication of the Club of Rome’s landmark report ‘The Limits to Growth’ in 1972 shook the intellectual foundations of social theory and challenged the very premises on which modern economy and prosperity are based. Once set in motion, it led to a revolutionary re-evaluation of human aspirations and economic activities. Among its many consequences, it has stimulated creative minds to look freshly at the underlying processes governing the wealth and welfare of nations. The article then traces their creative impact on the mind of one of the most original economic theorists of our age – Orio Giarini.[*] As ‘The Limits to Growth’ alarmed the world by the unsustainability and dire consequences of unbridled economic growth, Giarini offers a correspondingly affirmative vision of economics with unlimited potential for wealth and welfare.

  12. B cell-derived transforming growth factor-β1 expression limits the induction phase of autoimmune neuroinflammation

    Science.gov (United States)

    Bjarnadóttir, Kristbjörg; Benkhoucha, Mahdia; Merkler, Doron; Weber, Martin S.; Payne, Natalie L.; Bernard, Claude C. A.; Molnarfi, Nicolas; Lalive, Patrice H.

    2016-01-01

    Studies in experimental autoimmune encephalomyelitis (EAE), a murine model of multiple sclerosis (MS), have shown that regulatory B cells modulate the course of the disease via the production of suppressive cytokines. While data indicate a role for transforming growth factor (TGF)-β1 expression in regulatory B cell functions, this mechanism has not yet been tested in autoimmune neuroinflammation. Transgenic mice deficient for TGF-β1 expression in B cells (B–TGF-β1−/−) were tested in EAE induced by recombinant mouse myelin oligodendrocyte glycoprotein (rmMOG). In this model, B–TGF-β1−/− mice showed an earlier onset of neurologic impairment compared to their littermate controls. Exacerbated EAE susceptibility in B–TGF-β1−/− mice was associated with augmented CNS T helper (Th)1/17 responses. Moreover, selective B cell TGF-β1–deficiency increased the frequencies and activation of myeloid dendritic cells, potent professional antigen-presenting cells (APCs), suggesting that B cell-derived TGF-β1 can constrain Th1/17 responses through inhibition of APC activity. Collectively our data suggest that B cells can down-regulate the function of APCs, and in turn encephalitogenic Th1/17 responses, via TGF-β1, findings that may be relevant to B cell-targeted therapies. PMID:27708418

  13. Comparing nonsynergistic gamma models with interaction models to predict growth of emetic Bacillus cereus when using combinations of pH and individual undissociated acids as growth-limiting factors.

    Science.gov (United States)

    Biesta-Peters, Elisabeth G; Reij, Martine W; Gorris, Leon G M; Zwietering, Marcel H

    2010-09-01

    A combination of multiple hurdles to limit microbial growth is frequently applied in foods to achieve an overall level of protection. Quantification of hurdle technology aims at identifying synergistic or multiplicative effects and is still being developed. The gamma hypothesis states that inhibitory environmental factors aiming at limiting microbial growth rates combine in a multiplicative manner rather than synergistically. Its validity was tested here with respect to the use of pH and various concentrations of undissociated acids, i.e., acetic, lactic, propionic, and formic acids, to control growth of Bacillus cereus in brain heart infusion broth. The key growth parameter considered was the maximum specific growth rate, mu(max), as observed by determination of optical density. A variety of models from the literature describing the effects of various pH values and undissociated acid concentrations on mu(max) were fitted to experimental data sets and compared based on a predefined set of selection criteria, and the best models were selected. The cardinal model developed by Rosso (for pH dependency) and the model developed by Luong (for undissociated acid) were found to provide the best fit and were combined in a gamma model with good predictive performance. The introduction of synergy factors into the models was not able to improve the quality of the prediction. On the contrary, inclusion of synergy factors led to an overestimation of the growth boundary, with the inherent possibility of leading to underestimation of the risk under the conditions tested in this research.

  14. Substrate and nutrient limitation regulating microbial growth in soil

    Science.gov (United States)

    Bååth, Erland

    2015-04-01

    Microbial activity and growth in soil is regulated by several abiotic factors, including temperature, moisture and pH as the most important ones. At the same time nutrient conditions and substrate availability will also determine microbial growth. Amount of substrate will not only affect overall microbial growth, but also affect the balance of fungal and bacterial growth. The type of substrate will also affect the latter. Furthermore, according to Liebig law of limiting factors, we would expect one nutrient to be the main limiting one for microbial growth in soil. When this nutrient is added, the initial second liming factor will become the main one, adding complexity to the microbial response after adding different substrates. I will initially describe different ways of determining limiting factors for bacterial growth in soil, especially a rapid method estimating bacterial growth, using the leucine incorporation technique, after adding C (as glucose), N (as ammonium nitrate) and P (as phosphate). Scenarios of different limitations will be covered, with the bacterial growth response compared with fungal growth and total activity (respiration). The "degree of limitation", as well as the main limiting nutrient, can be altered by adding substrate of different stoichiometric composition. However, the organism group responding after alleviating the nutrient limitation can differ depending on the type of substrate added. There will also be situations, where fungi and bacteria appear to be limited by different nutrients. Finally, I will describe interactions between abiotic factors and the response of the soil microbiota to alleviation of limiting factors.

  15. FGF growth factor analogs

    Science.gov (United States)

    Zamora, Paul O [Gaithersburg, MD; Pena, Louis A [Poquott, NY; Lin, Xinhua [Plainview, NY; Takahashi, Kazuyuki [Germantown, MD

    2012-07-24

    The present invention provides a fibroblast growth factor heparin-binding analog of the formula: ##STR00001## where R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5, X, Y and Z are as defined, pharmaceutical compositions, coating compositions and medical devices including the fibroblast growth factor heparin-binding analog of the foregoing formula, and methods and uses thereof.

  16. Limited clinical efficacy of azacitidine in transfusion-dependent, growth factor-resistant, low- and Int-1-risk MDS

    DEFF Research Database (Denmark)

    Dybedahl, I; Holm, Mette; Karimi, M

    2014-01-01

    This prospective phase II study evaluated the efficacy of azacitidine (Aza)+erythropoietin (Epo) in transfusion-dependent patients with lower-risk myelodysplastic syndrome (MDS). Patients ineligible for or refractory to full-dose Epo+granulocyte colony stimulation factors for >8 weeks and a trans...

  17. PHYSICO-CHEMICAL LIMITATIVE FACTORS FOR GROWTH AND DEVELOPMENT IN STERLET (ACIPENSER RUTHENUS LINNAEUS, 1758 IN EXTENSIVELY SYSTEM

    Directory of Open Access Journals (Sweden)

    R. C. DIMA

    2013-07-01

    Full Text Available The oldest and most common method of increasing fish is a fish breeding ponds in which the supervision of nutrition and growth of biological material. Sterlet (Acipenser ruthenus ruthenus Linnaeus 1785 is the 4th of sturgeon scale and economic importance as a share of production of these fish .Monitoring of physicochemical parameters of sturgeons ponds has a crucial role to obtain satisfactory yields both in qualitative and quantitative. Chemical characteristics of water were determined in laboratory ecosystems Chemistry of the Institute of Research and Development for Ecology Aquaculture, Fisheries and Aquaculture Galaţi for the samples have been taken of the total water. Determination of the chemical characteristics was performed by standardized methods. Physic-chemical parameters of water were determined according to norm on the classification of surface water quality in order to establish the ecological status of water (Order no. 161/2006, for Class II of quality.

  18. Factors Limiting Microbial Growth and Activity at a Proposed High-Level Nuclear Repository, Yucca Mountain, Nevada

    OpenAIRE

    Kieft, T. L.; Kovacik, W. P.; Ringelberg, D B; White, D. C.; Haldeman, D. L.; Amy, P S; Hersman, L. E.

    1997-01-01

    As part of the characterization of Yucca Mountain, Nev., as a potential repository for high-level nuclear waste, volcanic tuff was analyzed for microbial abundance and activity. Tuff was collected aseptically from nine sites along a tunnel in Yucca Mountain. Microbial abundance was generally low: direct microscopic cell counts were near detection limits at all sites (3.2 x 10(sup4) to 2.0 x 10(sup5) cells g(sup-1) [dry weight]); plate counts of aerobic heterotrophs ranged from 1.0 x 10(sup1) ...

  19. New microbial growth factor

    Science.gov (United States)

    Bok, S. H.; Casida, L. E., Jr.

    1977-01-01

    A screening procedure was used to isolate from soil a Penicillium sp., two bacterial isolates, and a Streptomyces sp. that produced a previously unknown microbial growth factor. This factor was an absolute growth requirement for three soil bacteria. The Penicillium sp. and one of the bacteria requiring the factor, an Arthrobacter sp., were selected for more extensive study concerning the production and characteristics of the growth factor. It did not seem to be related to the siderochromes. It was not present in soil extract, rumen fluid, or any other medium component tested. It appears to be a glycoprotein of high molecular weight and has high specific activity. When added to the diets for a meadow-vole mammalian test system, it caused an increased consumption of diet without a concurrent increase in rate of weight gain.

  20. LXY6090 – a novel manassantin A derivative – limits breast cancer growth through hypoxia-inducible factor-1 inhibition

    OpenAIRE

    Lai, Fangfang; Liu, Qian; LIU, Xiaoyu; Ji, Ming; Xie, Ping; Chen, Xiaoguang

    2016-01-01

    Hypoxia-inducible factor-1 (HIF-1) represents a novel antitumor target owing to its involvement in vital processes considered hallmarks of cancer phenotypes. Manassantin A (MA) derived from Saururus cernuus has been reported as a selective HIF-1 inhibitor. Herein, the structure of MA was optimized to achieve new derivatives with simple chemical properties while retaining its activity. LXY6090 was designed to replace the central tetrahydrofuran moiety of MA with a cyclopentane ring and was ide...

  1. LXY6090 - a novel manassantin A derivative - limits breast cancer growth through hypoxia-inducible factor-1 inhibition.

    Science.gov (United States)

    Lai, Fangfang; Liu, Qian; Liu, Xiaoyu; Ji, Ming; Xie, Ping; Chen, Xiaoguang

    2016-01-01

    Hypoxia-inducible factor-1 (HIF-1) represents a novel antitumor target owing to its involvement in vital processes considered hallmarks of cancer phenotypes. Manassantin A (MA) derived from Saururus cernuus has been reported as a selective HIF-1 inhibitor. Herein, the structure of MA was optimized to achieve new derivatives with simple chemical properties while retaining its activity. LXY6090 was designed to replace the central tetrahydrofuran moiety of MA with a cyclopentane ring and was identified as a potent HIF-1 inhibitor with an IC50 value of 4.11 nM. It not only inhibited the activity of HIF-1 in breast cancer cells but also downregulated the protein level of HIF-1α, which depended on von Hippel-Lindau for proteasome degradation. The related biological evaluation showed that the activity of HIF-1 target genes, VEGF and IGF-2, was decreased by LXY6090 in breast cancer cell lines. LXY6090 presented potent antitumor activity in vitro. Furthermore, LXY6090 showed in vivo anticancer efficacy by decreasing the HIF-1α expression in nude mice bearing MX-1 tumor xenografts. In conclusion, our data provide a basis for the future development of the novel compound LXY6090 as a potential therapeutic agent for breast cancer.

  2. LXY6090 – a novel manassantin A derivative – limits breast cancer growth through hypoxia-inducible factor-1 inhibition

    Science.gov (United States)

    Lai, Fangfang; Liu, Qian; Liu, Xiaoyu; Ji, Ming; Xie, Ping; Chen, Xiaoguang

    2016-01-01

    Hypoxia-inducible factor-1 (HIF-1) represents a novel antitumor target owing to its involvement in vital processes considered hallmarks of cancer phenotypes. Manassantin A (MA) derived from Saururus cernuus has been reported as a selective HIF-1 inhibitor. Herein, the structure of MA was optimized to achieve new derivatives with simple chemical properties while retaining its activity. LXY6090 was designed to replace the central tetrahydrofuran moiety of MA with a cyclopentane ring and was identified as a potent HIF-1 inhibitor with an IC50 value of 4.11 nM. It not only inhibited the activity of HIF-1 in breast cancer cells but also downregulated the protein level of HIF-1α, which depended on von Hippel–Lindau for proteasome degradation. The related biological evaluation showed that the activity of HIF-1 target genes, VEGF and IGF-2, was decreased by LXY6090 in breast cancer cell lines. LXY6090 presented potent antitumor activity in vitro. Furthermore, LXY6090 showed in vivo anticancer efficacy by decreasing the HIF-1α expression in nude mice bearing MX-1 tumor xenografts. In conclusion, our data provide a basis for the future development of the novel compound LXY6090 as a potential therapeutic agent for breast cancer. PMID:27445487

  3. Landscape genetics and limiting factors

    Science.gov (United States)

    Samuel A. Cushman; Andrew J. Shirk; Erin L. Landguth

    2013-01-01

    Population connectivity is mediated by the movement of organisms or propagules through landscapes. However, little is known about how variation in the pattern of landscape mosaics affects the detectability of landscape genetic relationships. The goal of this paper is to explore the impacts of limiting factors on landscape genetic processes using simulation...

  4. Pars plana vitrectomy combined with internal limiting membrane peeling for recurrent macular edema due to branch retinal vein occlusion after antivascular endothelial growth factor treatments

    Directory of Open Access Journals (Sweden)

    Shirakata Y

    2016-02-01

    Full Text Available Yukari Shirakata,1 Kouki Fukuda,1 Tomoyoshi Fujita,1 Yuki Nakano,1 Hiroyuki Nomoto,2 Hidetaka Yamaji,3 Fumio Shiraga,4 Akitaka Tsujikawa1 1Department of Ophthalmology, Faculty of Medicine, Kagawa University, Miki-cho, 2Nomoto Eye Clinic, Himeji, 3Department of Ophthalmology, Shirai Eye Hospital, Mitoyo, 4Department of Ophthalmology, Okayama University, Okayama, Japan Purpose: To evaluate the anatomic and functional outcomes of pars plana vitrectomy combined with internal limiting membrane peeling for recurrent macular edema (ME due to branch retinal vein occlusion (BRVO after intravitreal injections of antivascular endothelial growth factor (anti-VEGF agents. Methods: Twenty-four eyes of 24 patients with treatment-naive ME from BRVO were treated with intravitreal injections of anti-VEGF agents. Recurred ME was treated with pars plana vitrectomy combined with internal limiting membrane peeling. Results: After the surgery, ME was significantly reduced at 1 month (P=0.031 and the reduction increased with time (P=0.007 at the final visit. With the reduction in ME, treated eyes showed a slow improvement in visual acuity (VA. At the final visit, improvement in VA was statistically significant compared with baseline (P=0.048. The initial presence of cystoid spaces, serous retinal detachment, or subretinal hemorrhage under the fovea, as well as retinal perfusion status, showed no association with VA improvement. However, the presence of epiretinal membrane showed a significant association with the visual recovery. Although eyes without epiretinal membrane showed visual improvement (-0.10±0.32 in logarithm of the minimum angle of resolution [logMAR], eyes with epiretinal membrane showed greater visual improvement (-0.38±0.12 in logMAR, P=0.012. Conclusion: For recurrent ME due to BRVO after anti-VEGF treatment, particularly when accompanied by epiretinal membrane, pars plana vitrectomy combined with internal limiting membrane peeling might be a

  5. In normal rat, intraventricularly administered insulin-like growth factor-1 is rapidly cleared from CSF with limited distribution into brain

    Directory of Open Access Journals (Sweden)

    Gorevic Peter D

    2005-07-01

    Full Text Available Abstract Background Putatively active drugs are often intraventricularly administered to gain direct access to brain and circumvent the blood-brain barrier. A few studies on the normal central nervous system (CNS have shown, however, that the distribution of materials after intraventricular injections is much more limited than presumed and their exit from cerebrospinal fluid (CSF is more rapid than generally believed. In this study, we report the intracranial distribution and the clearance from CSF and adjacent CNS tissue of radiolabeled insulin-like growth factor-1 after injection into one lateral ventricle of the normal rat brain. Methods Under barbiturate anesthesia, 125I-labeled insulin-like growth factor-1 (IGF-1 was injected into one lateral ventricle of normal Sprague-Dawley rats. The subsequent distribution of IGF-1 through the cerebrospinal fluid (CSF system and into brain, cerebral blood vessels, and systemic blood was measured over time by gamma counting and quantitative autoradiography (QAR. Results Within 5 min of infusion, IGF-1 had spread from the infused lateral ventricle into and through the third and fourth ventricles. At this time, 25% of the infused IGF-1 had disappeared from the CSF-brain-meningeal system; the half time of this loss was 12 min. The plasma concentration of cleared IGF-1 was, however, very low from 2 to 9 min and only began to rise markedly after 20 min. This delay between loss and gain plus the lack of radiotracer in the cortical subarachnoid space suggested that much of the IGF-1 was cleared into blood via the cranial and/or spinal nerve roots and their associated lymphatic systems rather than periventricular tissue and arachnoid villi. Less than 10% of the injected radioactivity remained in the CSF-brain system after 180 min. The CSF and arteries and arterioles within the subarachnoid cisterns were labeled with IGF-1 within 10 min. Between 60 and 180 min, most of the radioactivity within the cranium was

  6. Limiting factors of starch hydrolysis.

    Science.gov (United States)

    Colonna, P; Leloup, V; Buléon, A

    1992-10-01

    Foods appear as complex structures, in which starch may be present in different forms. These, including the molecular characteristics and the crystalline organization, depend on processing conditions and compositions of ingredients. The main changes in starch macro- and microstructures are the increase of surface area to volume ratio in the solid phase, the modification of the crystallinity as affected by gelatinization and gelation, and the depolymerization of amylose and amylopectin. Starch modification may be estimated by different methodologies, which should be selected according to the level of structure considered. When amylose and amylopectin are in solution, rapid and total hydrolysis leads to the formation of a mixture of linear oligosaccharides and branched alpha-limit dextrins. However, starch usually occurs in foods as solid structures. Structural factors of starchy materials influence their enzymic hydrolysis. A better understanding of the enzymatic process enables the identification of the structural factors limiting hydrolysis: diffusion of enzyme molecules, porosity of solid substrates, adsorption of enzymes onto solid substrates, and the catalytic event. A mechanistic modelling should be possible in the future.

  7. Dual surrogate markers for rapid prediction of epidermal growth factor receptor mutation status in advanced adenocarcinoma of the lung: A novel approach in resource-limited setting

    Directory of Open Access Journals (Sweden)

    K S Udupa

    2015-01-01

    Full Text Available Introduction: Tyrosine kinase inhibitors have revolutionized the treatment of metastatic lung cancer in patients with epidermal growth factor receptor (EGFR mutations. Amplified refractory mutation system (ARMS-reverse transcription-polymerase chain reaction (RT-PCR, the current standard for detecting EGFR mutation status is time-consuming and highly expensive. Consequently any surrogate test which are cheaper, faster and as accurate as the PCR method will help in early diagnosis and management of patients with lung cancer, especially in resource-limited settings. Materials and Methods: Eighty-five patients, all of South Indian origin, with adenocarcinoma of lung, registered between October 2009 and January 2013, were evaluated for EGFR mutation status by using scorpion probe based ARMS RT-PCR method. Immunohistochemical (IHC was performed using the phosphorylated AKT (P-AKT and thyroid transcription factor-1 (TTF-1 on above patient's sample, and the results were compared with EGFR mutation tests. Results: EGFR mutation was positive in 34 of 85 patients (40%. P-AKT and TTF-1 were positive in 50 (58.8% and 68 (80% patients respectively. Both P-AKT and TTF-1 had statistically significant correlation with EGFR mutation status. Positive and negative predictive value of P-AKT in diagnosing EGFR mutation was 58% and 85.5% and that for TTF-1 was 48.5% and 94.1%, respectively. The problem of low positive predictive value can partly be overcome by testing P-AKT and TTF-1 simultaneously. Conclusion: P-AKT and TTF-1 using IHC had statistically significant correlation with EGFR mutation with high negative predictive value. In the case of urgency of starting treatment, EGFR mutation testing may be avoided in those patients who are negative for these IHC markers and can be started on chemotherapy.

  8. Physiological factors influencing capillary growth.

    Science.gov (United States)

    Egginton, S

    2011-07-01

    (1) Angiogenesis (growth of new capillaries from an existing capillary bed) may result from a mismatch in microvascular supply and metabolic demand (metabolic error signal). Krogh examined the distribution and number of capillaries to explore the correlation between O(2) delivery and O(2) consumption. Subsequently, the heterogeneity in angiogenic response within a muscle has been shown to reflect either differences in fibre type composition or mechanical load. However, local control leads to targetted angiogenesis in the vicinity of glycolytic fibre types following muscle stimulation, or oxidative fibres following endurance training, while heterogeneity of capillary spacing is maintained during ontogenetic growth. (2) Despite limited microscopy resolution and lack of specific markers, Krogh's interest in the structure of the capillary wall paved the way for understanding the mechanisms of capillary growth. Angiogenesis may be influenced by the response of perivascular or stromal cells (fibroblasts, macrophages and pericytes) to altered activity, likely acting as a source for chemical signals modulating capillary growth such as vascular endothelial growth factor. In addition, haemodynamic factors such as shear stress and muscle stretch play a significant role in adaptive remodelling of the microcirculation. (3) Most indices of capillarity are highly dependent on fibre size, resulting in possible bias because of scaling. To examine the consequences of capillary distribution, it is therefore helpful to quantify the area of tissue supplied by individual capillaries. This allows the spatial limitations inherent in most models of tissue oxygenation to be overcome generating an alternative approach to Krogh's tissue cylinder, the capillary domain, to improve descriptions of intracellular oxygen diffusion. © 2010 The Author. Acta Physiologica © 2010 Scandinavian Physiological Society.

  9. Growth hormone, growth factors, and acromegaly

    Energy Technology Data Exchange (ETDEWEB)

    Ludecke, D.K.; Tolis, G.T.

    1987-01-01

    This book contains five sections, each consisting of several papers. The section headings are: Biochemistry and Physiology of GH and Growth Factors, Pathology of Acromegaly, Clinical Endocrinology of Acromegaly, Nonsurgical Therapy of Acromegaly, and Surgical Therapy of Acromegaly.

  10. The evolution of growth trajectories: what limits growth rate?

    Science.gov (United States)

    Dmitriew, Caitlin M

    2011-02-01

    According to life-history theory, growth rates are subject to strong directional selection due to reproductive and survival advantages associated with large adult body size. Yet, growth is commonly observed to occur at rates lower than the maximum that is physiologically possible and intrinsic growth rates often vary among populations. This implies that slower growth is favoured under certain conditions. Realized growth rate is thus the result of a compromise between the costs and advantages of growing rapidly, and the optimal rate of growth is not equivalent to the fundamental maximum rate. The ecological and evolutionary factors influencing growth rate are reviewed, with particular emphasis on how growth might be constrained by direct fitness costs. Costs of accelerating growth might contribute to the variance in fitness that is not attributable to age or size at maturity, as well as to the variation in life-history strategies observed within and among species. Two main approaches have been taken to study the fitness trade-offs relating to growth rate. First, environmental manipulations can be used to produce treatment groups with different rates of growth. Second, common garden experiments can be used to compare fitness correlates among populations with different intrinsic growth rates. Data from these studies reveal a number of potential costs for growth over both the short and long term. In order to acquire the energy needed for faster growth, animals must increase food intake. Accordingly, in many taxa, the major constraint on growth rate appears to arise from the trade-off between predation risk and foraging effort. However, growth rates are also frequently observed to be submaximal in the absence of predation, suggesting that growth trajectories also impact fitness via other channels, such as the reallocation of finite resources between growth and other traits and functions. Despite the prevalence of submaximal growth, even when predators are absent, there

  11. Economic Limits to Corporate Growth in America

    Science.gov (United States)

    2006-12-01

    question of how fast the economy can grow. Economists such as Krugman (1997) and Blinder (1997) both predicted inherent limits on U.S. economic growth...Age. Brookings Papers on Economic Activity, 1:2000, 125-235. Krugman , P. (1997). How fast can the U.S. economy grow? Harvard Business Review, (July

  12. The History of the Limits to Growth

    DEFF Research Database (Denmark)

    Nørgaard, Jørgen; Ragnarsdóttir, Kristín Vala; Peet, John

    2010-01-01

    The report The Limits to Growth was in many ways a breakthrough in the way the future was debated and analysed as far as the physical economy was concerned. The paper describes how the very title seems to have offended many people, leading a cohort of critics to reject the report as a doomsday...

  13. Growth Limits in Large Scale Networks

    DEFF Research Database (Denmark)

    Knudsen, Thomas Phillip

    the fundamental technological resources in network technologies are analysed for scalability. Here several technological limits to continued growth are presented. The third step involves a survey of major problems in managing large scale networks given the growth of user requirements and the technological...... limitations. The rising complexity of network management with the convergence of communications platforms is shown as problematic for both automatic management feasibility and for manpower resource management. In the fourth step the scope is extended to include the present society with the DDN project as its...... main focus. Here the general perception of the nature and role in society of large scale networks as a fundamental infrastructure is analysed. This analysis focuses on the effects of the technical DDN projects and on the perception of network infrastructure as expressed by key decision makers...

  14. Comparing nonsynergistic gamma models with interaction models to predict growth of emetic Bacillus cereus when using combinations of pH and individual undissociated acids as growth-limiting factors

    NARCIS (Netherlands)

    Biesta-Peters, E.G.; Reij, M.W.; Gorris, L.G.M.; Zwietering, M.H.

    2010-01-01

    A combination of multiple hurdles to limit microbial growth is frequently applied in foods to achieve an overall level of protection. Quantification of hurdle technology aims at identifying synergistic or multiplicative effects and is still being developed. The gamma hypothesis states that inhibitor

  15. Growth factors and new periodontology

    Directory of Open Access Journals (Sweden)

    Paknejad M

    1999-06-01

    Full Text Available Growth factors are biological mediators that have a key roll in proliferation, chemotaxy and"ndifferentiation by acting on specific receptors on the surface of cells and regulating events in wound"nhealing.They can be considered hormones that are not released in to the blood stream but have one a"nlocal action. Some of these factors can regulate premature change in GO to Gl phase in cell devesion"ncycle and even may stimulate synthesis of DNA in suitable cells, Growth substances, primarily secreted"nby fibroblasts, endothelia! cells, macrophages and platelet, include platelet derived growth factor"n(PDGF, insulin like growth factor (IGF transforming growth factor (TGFa and (3 and bone"nmorphogenetic proteins BMPs that approximately are the most important of them. (BMPs could be"nused to control events during periodontal, craniofacial and implant wound healing through favoring bone"nformation"nAccording toLynch, combination of PGDF and IGF1 would be effective in promoting growth of all the"ncomponents of the periodontium."nThe aim of this study was to characterize growth factor and review the literature to determine the"nmechanism of their function, classification and application in implant and periodontal treatment.

  16. Nutrients that limit growth in the ocean.

    Science.gov (United States)

    Bristow, Laura A; Mohr, Wiebke; Ahmerkamp, Soeren; Kuypers, Marcel M M

    2017-06-05

    Phytoplankton form the basis of the marine food web and are responsible for approximately half of global carbon dioxide (CO2) fixation (∼ 50 Pg of carbon per year). Thus, these microscopic, photosynthetic organisms are vital in controlling the atmospheric CO2 concentration and Earth's climate. Phytoplankton are dependent on sunlight and their CO2-fixation activity is therefore restricted to the upper, sunlit surface ocean (that is, the euphotic zone). CO2 usually does not limit phytoplankton growth due to its high concentration in seawater. However, the vast majority of oceanic surface waters are depleted in inorganic nitrogen, phosphorus, iron and/or silica; nutrients that limit primary production in the ocean (Figure 1). Phytoplankton growth is mainly supported by either the recycling of nutrients or by reintroduction of nutrients from deeper waters by mixing. A small percentage of primary production, though, is fueled by 'external' or 'new' nutrients and it is these nutrients that determine the amount of carbon that can be sequestered long term in the deep ocean. For most nutrients such as phosphorus, iron, and silica, the external supply is limited to atmospheric deposition and/or coastal and riverine inputs, whereas their main sink is the sedimentation of particulate matter. Nitrogen, however, has an additional, biological source, the fixation of N2 gas, as well as biological sinks via the processes of denitrification and anammox. Despite the comparatively small contributions to the overall turnover of nutrients in the ocean, it is these biological processes that determine the ocean's capacity to sequester CO2 from the atmosphere on time scales of ocean circulation (∼ 1000 years). This primer will highlight shifts in the traditional paradigms of nutrient limitation in the ocean, with a focus on the uniqueness of the nitrogen cycling and its biological sources and sinks. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. The development of decision limits for the GH-2000 detection methodology using additional insulin-like growth factor-I and amino-terminal pro-peptide of type III collagen assays

    OpenAIRE

    Holt, Richard I.G.; Böhning, Walailuck; Guha, Nishan; Bartlett, Christiaan; David A. Cowan; Giraud, Sylvain; Bassett, E. Eryl; Sönksen, Peter H.; Böhning, Dankmar

    2015-01-01

    The GH-2000 and GH-2004 projects have developed a method for detecting GH misuse based on measuring insulin-like growth factor-I (IGF-I) and the amino-terminal pro-peptide of type III collagen (P-III-NP). The objectives were to analyze more samples from elite athletes to improve the reliability of the decision limit estimates, to evaluate whether the existing decision limits needed revision, and to validate further non-radioisotopic assays for these markers. The study included 998 male and 93...

  18. Ceramic materials and growth factors

    Energy Technology Data Exchange (ETDEWEB)

    Ohgushi, H.; Yoshikawa, T.; Okumura, M.; Nakajima, H.; Takakura, Y. [Nara Medical Univ. (Japan). Dept. of Orhtopaedic Surgery; Dohi, Y. [Nara Medical Univ. (Japan). Dept. of Public Health; Noshi, T.; Ikeuchi, M. [Nara Medical Univ. (Japan). Dept. of Oral and Maxillofacial Surgery

    2001-07-01

    Recently, many types of growth factors have been purified and used for promoting cell differentiation cascade. The activity of growth factors can be detected in vitro such as culture condition. However, the activity is difficult to detect when these factors are locally administered in vivo, because these dissipate soon after the administration. In order to retain growth factors in local milieu, these can be incorporated with biocompatible porous ceramic materials. Such ceramic/factors composites when implanted in vivo, can trigger certain types of cell differentiation cascade resulted in new tissue formation and tissue regeneration. The paper describes the ceramic / growth factors composites especially hydroxyapatite ceramic (HA) / bone morphogenetic protein (BMP) composite to induce osteoblastic differentiation of mesenchymal stem cells. The HA/BMP composite supported the osteoblastic differentiation on the HA surface and finally resulted in bone bonding to the HA. When the marrow mesenchymal stem cells (MSCs) were impregnated in pore areas of HA ceramics, the composites showed more and rapid bone formation than the HA/BMP and HA/MSCs composite, indicating the synergistic effect of BMP and MSCs. These findings indicate the importance of ceramic surface to evoke osteoblastic differentiation as well as to capture the molecules of growth factors for the cell differentiation. (orig.)

  19. Growth Factors in Synaptic Function

    Directory of Open Access Journals (Sweden)

    Vivian Yi Nuo Poon

    2013-09-01

    Full Text Available Synapses are increasingly recognized as key structures that malfunction in disorders like schizophrenia, mental retardation, and neurodegenerative diseases. The importance and complexity of the synapse has fuelled research into the molecular mechanisms underlying synaptogenesis, synaptic transmission, and plasticity. In this regard, neurotrophic factors such as netrin, Wnt, transforming growth factor-beta (TGF-beta, tumor necrosis factor-α (TNF-α, and others have gained prominence for their ability to regulate synaptic function. Several of these factors were first implicated in neuroprotection, neuronal growth, and axon guidance. However, their roles in synaptic development and function have become increasingly clear, and the downstream signaling pathways employed by these factors have begun to be elucidated. In this review, we will address the role of these factors and their downstream effectors in synaptic function in vivo and in cultured neurons.

  20. Planetary Overload, Limits to Growth and Health.

    Science.gov (United States)

    Butler, Colin D

    2016-12-01

    Since the use of atomic weapons in 1945 visionaries have warned that without major changes the survival of global civilization is in question. These concerns deepened in following decades, during the Cold War, with The Limits to Growth, the best-selling environmental book of the 1970s. Yet, since then, most concern has faded, fuelled by technological developments and a shift in dominant global ideology. Public health, with a few exceptions (one of which is the book Planetary Overload), has been slow to recognize this debate, even as evidence emerges that civilization may indeed be at risk, driven by an increasingly ominous complex of events. This article outlines the key relevant literature and concepts, attempting to bring emerging and future health consequences to the attention of health workers, including the idea of a "social vaccine," conveying sufficient anxiety to provoke action for environmental protection, but insufficient to induce paralysis.

  1. Engineering growth factors for regenerative medicine applications.

    Energy Technology Data Exchange (ETDEWEB)

    Mitchell, Aaron C.; Briquez, Priscilla S.; Hubbell, Jeffrey A.; Cochran, Jennifer R.

    2016-01-15

    Growth factors are important morphogenetic proteins that instruct cell behavior and guide tissue repair and renewal. Although their therapeutic potential holds great promise in regenerative medicine applications, translation of growth factors into clinical treatments has been hindered by limitations including poor protein stability, low recombinant expression yield, and suboptimal efficacy. This review highlights current tools, technologies, and approaches to design integrated and effective growth factor-based therapies for regenerative medicine applications. The first section describes rational and combinatorial protein engineering approaches that have been utilized to improve growth factor stability, expression yield, biodistribution, and serum half-life, or alter their cell trafficking behavior or receptor binding affinity. The second section highlights elegant biomaterial-based systems, inspired by the natural extracellular matrix milieu, that have been developed for effective spatial and temporal delivery of growth factors to cell surface receptors. Although appearing distinct, these two approaches are highly complementary and involve principles of molecular design and engineering to be considered in parallel when developing optimal materials for clinical applications.

  2. Limiting factors in caribou population ecology

    Directory of Open Access Journals (Sweden)

    David R. Klein

    1991-10-01

    Full Text Available Caribou and wild reindeer populations fluctuate over time. On this fact there is general agreement. Factors responsible for population limitation and subsequent declines have been examined within the framework of animal population theory. There is, however, little agreement when factors limiting specific populations are generalized to Rangifer populations over broad geographic regions. Comparative examinations of wild Rangifer populations worldwide discloses that factors that have regulated those populations are highly variable between populations, apparently as a reflection of the differences in environmental variables unique to each population. Examples exist of populations where major regulating factors have been climatic extremes, predation, hunting mortality, food limitation, insects, parasites, disease, interspecific competition, and human developmental impacts or combinations of these factors. This diversity of limiting factors affecting caribou and wild reindeer populations is a reflection of the ecologial complexity of the species, a concept that has often been ignored in past efforts to reach management decisions by extrapolation from the limited localized knowledge available on the species.

  3. Growth factors in orthopedic surgery.

    Science.gov (United States)

    Zaharia, Comeliu; Niculescu, Marius; Despa, Nicoleta; Simionescu, Maya; Jinga, Victor; Fleseriu, Irina

    2010-01-01

    Growth factors have represented an essential issue of interest for the researchers and clinicians in orthopedics and trauma over the last 40 years. In the last 10 to 15 years, the advances registered in this field have permitted the identification of the most active cellular and humoral factors as well as the improvement of their use in the orthopedic and trauma surgery. Their domain of application has been continuously enlarged and the results have been visible from the beginning. The authors present their appreciation on the actual state of this subject as well as their experience with results and related conclusions.

  4. Discrete stochastic Laplacian growth: classical limit

    CERN Document Server

    Alekseev, Oleg

    2016-01-01

    Many tiny particles, emitted incessantly from stochastic sources on a plane, perform Brownian motion until they stick to a cluster, so providing its growth. The growth probability is presented as a sum over all possible "scenaria", leading to the same final complex shape. The logarithm of the probability (negative action) has the familiar entropy form, and its global maximum is shown to be exactly the deterministic equation of Laplacian growth with many sources. The full growth probability, which includes probability of creation of random sources, is presented in two forms of electrostatic energy. It is also found to be factorizable in a complex plane, where the exterior of the unit disk maps conformally to the exterior of the growing cluster. The obtained action is analyzed from a potential-theoretical point of view, and its connections with the tau-function of the integrable Toda hierarchy and with the Liouville theory for non-critical strings are established.

  5. Credit And Growth Under Limited Commitment

    OpenAIRE

    Azariadis, Costas; Kaas, Leo

    2008-01-01

    We consider a linear growth model with idiosyncratic productivity shocks in which producers cannot commit to repay their loans. Borrowing constraints are determined endogenously by the borrowers incentives to repay, assuming that defaulters lose a share of output and are excluded from future trade in the credit market. We characterize necessary and sufficient conditions for the enforceability of a first-best equilibrium growth path. Weak property rights, impatient producers, and small produc...

  6. LXY6090 – a novel manassantin A derivative – limits breast cancer growth through hypoxia-inducible factor-1 inhibition

    Directory of Open Access Journals (Sweden)

    Lai F

    2016-06-01

    Full Text Available Fangfang Lai,1 Qian Liu,2 Xiaoyu Liu,3 Ming Ji,1 Ping Xie,3 Xiaoguang Chen1 1Department of Pharmacology, State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, 2Department of Pharmacology, National Institutes for Food and Drug Control, 3Department of Pharmacochemistry, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, People’s Republic of China Abstract: Hypoxia-inducible factor-1 (HIF-1 represents a novel antitumor target owing to its involvement in vital processes considered hallmarks of cancer phenotypes. Manassantin A (MA derived from Saururus cernuus has been reported as a selective HIF-1 inhibitor. Herein, the structure of MA was optimized to achieve new derivatives with simple chemical properties while retaining its activity. LXY6090 was designed to replace the central tetrahydrofuran moiety of MA with a cyclopentane ring and was identified as a potent HIF-1 inhibitor with an IC50 value of 4.11 nM. It not only inhibited the activity of HIF-1 in breast cancer cells but also downregulated the protein level of HIF-1α, which depended on von Hippel–Lindau for proteasome degradation. The related biological evaluation showed that the activity of HIF-1 target genes, VEGF and IGF-2, was decreased by LXY6090 in breast cancer cell lines. LXY6090 presented potent antitumor activity in vitro. Furthermore, LXY6090 showed in vivo anticancer efficacy by decreasing the HIF-1α expression in nude mice bearing MX-1 tumor xenografts. In conclusion, our data provide a basis for the future development of the novel compound LXY6090 as a potential therapeutic agent for breast cancer. Keywords: hypoxia-inducible factor-1, manassantin A derivative, antitumor, breast cancer, LXY6090

  7. Factors Behind Industrial Profit Growth

    Institute of Scientific and Technical Information of China (English)

    郑玉歆; 李玉红

    2008-01-01

    This paper analyzes Chinese enterprise industrial profit distribution and profitability rise between 1998 and 2005. Looking at it from the perspective of drivers of total growth, this paper will provide an in-depth analysis of the origins and industry-level factors involved in this growth. It reaches the conclusion that structural change in profits was the main driving force for profit increases, to which heavy industry contributed greatly. Light and machine building industry profit rates improved due to increases in productivity levels, while energy and raw material industry profits increased due to increases in product prices. In addition, average wages grew slower than GDP, and wages among industries varied widely. In general however, this paper sets out to determine which enterprises gained from increases in industrial profitability, and how this gain came about.

  8. The development of decision limits for the GH-2000 detection methodology using additional insulin-like growth factor-I and amino-terminal pro-peptide of type III collagen assays.

    Science.gov (United States)

    Holt, Richard I G; Böhning, Walailuck; Guha, Nishan; Bartlett, Christiaan; Cowan, David A; Giraud, Sylvain; Bassett, E Eryl; Sönksen, Peter H; Böhning, Dankmar

    2015-09-01

    The GH-2000 and GH-2004 projects have developed a method for detecting GH misuse based on measuring insulin-like growth factor-I (IGF-I) and the amino-terminal pro-peptide of type III collagen (P-III-NP). The objectives were to analyze more samples from elite athletes to improve the reliability of the decision limit estimates, to evaluate whether the existing decision limits needed revision, and to validate further non-radioisotopic assays for these markers. The study included 998 male and 931 female elite athletes. Blood samples were collected according to World Anti-Doping Agency (WADA) guidelines at various sporting events including the 2011 International Association of Athletics Federations (IAAF) World Athletics Championships in Daegu, South Korea. IGF-I was measured by the Immunotech A15729 IGF-I IRMA, the Immunodiagnostic Systems iSYS IGF-I assay and a recently developed mass spectrometry (LC-MS/MS) method. P-III-NP was measured by the Cisbio RIA-gnost P-III-P, Orion UniQ™ PIIINP RIA and Siemens ADVIA Centaur P-III-NP assays. The GH-2000 score decision limits were developed using existing statistical techniques. Decision limits were determined using a specificity of 99.99% and an allowance for uncertainty because of the finite sample size. The revised Immunotech IGF-I - Orion P-III-NP assay combination decision limit did not change significantly following the addition of the new samples. The new decision limits are applied to currently available non-radioisotopic assays to measure IGF-I and P-III-NP in elite athletes, which should allow wider flexibility to implement the GH-2000 marker test for GH misuse while providing some resilience against manufacturer withdrawal or change of assays.

  9. Evaluation of Factors Limiting Corneal Donation.

    Science.gov (United States)

    Röck, Daniel; Wude, Johanna; Yoeruek, Efdal; Bartz-Schmidt, Karl Ulrich; Röck, Tobias

    2016-11-15

    BACKGROUND This study aimed to investigate factors limiting corneal donation at the University Hospital Tübingen. MATERIAL AND METHODS We retrospectively studied all hospital deaths from January 2012 to December 2015, considering each deceased patient as a potential corneal donor. During this period an ophthalmic resident managed corneal donor procurement on a full-time basis. Various factors limiting corneal donation were examined. RESULTS Among the 3412 deaths, 2937 (86.1%) displayed nonfulfillment of corneal donation. Consent for corneal donation was obtained in 475 cases (13.9%). The mean annual corneal donation rate was 13.9 donors per 100 deaths (range: 11.2-17.8). The leading causes of nonfulfillment of corneal donations were refusal to donate (49.8%, 1698 cases) and medical contraindications (23.6%, 805 cases). After next-of-kin interview of 2173 potential donors (109 potential donors were excluded because of logistical problems), willingness to participate in corneal donation was present in 475 cases (21.9%), whereas in 1698 cases (78.1%) corneal donation was refused. CONCLUSIONS Our study showed refusal to donate is the most important factor limiting corneal donation. It seems that increasing the knowledge of people about corneal donation through public education and media are necessary to address the corneal shortage.

  10. Growth factors and cytokines in acute renal failure.

    Science.gov (United States)

    Harris, R C

    1997-04-01

    The mammalian kidney is susceptible to injury by ischemia/reperfusion and toxins, and regeneration after injury is characterized by hyperplasia and recovery of the damaged epithelial cells that line the tubules. Locally produced growth factors may serve as mediators of nephrogenesis and differentiation during renal development and of renal regeneration after acute injury. In cultured cells, administration of one or a mixture of growth factors to quiescent cells will initiate progression through the cell cycle and cell division. In the adult kidney, cell division normally is very low, but will increase up to 10-fold after acute injury. In addition to proliferation after lethal injury, there also is cellular repair in cells that have undergone sublethal injury. Recent studies indicate that growth factors inhibit programmed cell death in response to acute injury. Growth factors also may initiate or promote protein and lipid biosynthesis and provide an intracellular milieu that promotes cellular repair. In addition to cellular repair, growth factors also may be involved in the re-establishment of cell-extracellular matrix and cell-cell integrity. Finally, growth factors may limit injury by decreasing the factors that induce damage. Increased local renal expression of growth factors in response to acute injury include heparin binding epidermal growth factor (HB-EGF), hepatocyte growth factor (HGF), insulin-like growth factor-I (IGF-I), transforming growth factor-beta, parathyroid hormone-related peptide, and acidic fibroblast growth factor. In a number of experimental models of acute renal injury, administration of exogenous growth factors has been shown to accelerate both structural and functional recovery. Specifically, EGF, IGF-1, and HGF all have been shown to be effective in this regard. These studies are reviewed and potential therapeutic uses of growth factors and cytokines will be discussed.

  11. Limits to solar and biomass energy growth

    Energy Technology Data Exchange (ETDEWEB)

    Schiffman, Y.M.; D' Alessio, G.J.

    1983-01-01

    Drawing on some 45 assessments made by the Technology Assessments of Solar Energy (TASE), the authors examine the potential for commercialization of solar and biomass technologies. The book is divided into four major parts: Part I describes and compares technologies; Part II describes the natural and capital resources necessary for commercialization; Part III examines social, economic, and environmental impacts and institutional and regulatory factors; and Part IV analyzes the consequences of several deployment scenarios. The authors conclude that the disproportionate resource requirements for a modest energy contribution will be liminting factor. 103 references, 80 figures, 32 tables. (DCK)

  12. Erosion and the limits to planetesimal growth

    CERN Document Server

    Krijt, Sebastiaan; Dominik, Carsten; Tielens, Alexander G G M

    2014-01-01

    The coagulation of microscopic dust into planetesimals is the first step towards planet formation. The size and shape of the growing aggregates determine the efficiency of this early growth. It has been proposed that fluffy ice aggregates can grow very efficiently, suffering less from the bouncing and radial drift barriers. While the collision velocity between icy aggregates of similar size is thought to stay below the fragmentation threshold, they may nonetheless lose mass from collisions with much smaller projectiles. We investigate the effect of these erosive collisions on the ability of porous ice aggregates to cross the radial drift barrier. We develop a Monte Carlo code that calculates the evolution of the growing aggregates, while resolving the entire mass distribution at all times. The aggregate's porosity is treated independently of its mass, and is determined by collisions, gas compaction, and eventually self-gravity compaction. For erosion threshold velocities of 20-40 m/s, high-velocity collisions...

  13. New detection methods of growth hormone and growth factors.

    Science.gov (United States)

    Bidlingmaier, Martin

    2012-01-01

    Human growth hormone (GH), but also GH related growth factors like the insulin-like growth factor-1 (IGF-1) are known to be abused in sports. Although the scientific evidence supporting a distinct effect of GH on performance in healthy trained subjects is limited, it has been repeatedly found with athletes or trainers, and the recent introduction of a first test to detect GH doping has led to a number of positive cases. Currently, there is no test for the detection of IGF-1 introduced worldwide, but confiscation of the drug from sports teams can be taken as indirect evidence for its abuse. The major biochemical difficulty for the detection of GH is that the recombinant form is identical in physicochemical properties to the endogenous GH secreted by the pituitary gland. Furthermore, the very short half-life of GH in circulation inherently shortens the window of opportunity where the drug can be detected. Two strategies have been followed for more than a decade to develop a test to detect the application of recombinant GH: the marker approach, which is based on the elevation of GH-dependent markers above the level seen under physiological conditions evoked by administration of recombinant GH, and the isoform approach, which is based on a change in the pattern of GH isoforms in circulation following the injection of recombinant GH.

  14. Physiological requirements for growth and competitiveness of Dekkera bruxellensis under oxygen‐limited or anaerobic conditions

    National Research Council Canada - National Science Library

    Blomqvist, Johanna; Nogué, Violeta Sànchez; Gorwa‐Grauslund, Marie; Passoth, Volkmar

    2012-01-01

    The effect of glucose and oxygen limitation on the growth and fermentation performances of Dekkera bruxellensis was investigated in order to understand which factors favour its propagation in ethanol or wine plants. Although D...

  15. The growth of foot arches and influencing factors

    OpenAIRE

    Ferial Hadipoetro Idris

    2016-01-01

    Background Foot arches are important components for body sup- port. Foot arch deformity caused by growth abnormalities cause serious limitations in daily activities. Objectives To determine the patterns of foot arch growth, factors influencing foot arch growth, and the timing for intervention in er- rant growth patterns. Methods A cross-sectional study evaluated the foot arches of chil- dren aged 0-18 years according to age and sex. Subjects included had no evidence of...

  16. Is iron a limiting factor of Nodularia spumigena blooms?

    Directory of Open Access Journals (Sweden)

    Lidia Paczuska

    2003-12-01

    Full Text Available It is well known that a deficiency of iron, a trace element essential to every living organism, limits the growth of algae and cyanobacteria. Nodularia spumigena Mertens is a blue-green algae species inhabiting the Baltic region that often forms toxic blooms.     The aim of the study was to assess the growth of the toxic cyanobacteria with respect to iron bioavailability. The measured growth parameters were the numbers of cells (optical density, chlorophyll a and pheopigment a concentrations. The iron concentrations used ranged from 10-7 to 10-4 mol dm-3. Under iron stress conditions (<5 × 10-7 mol dm-3, growth inhibition, gradual pigment decay and cell mortality were observed. However, enriching the medium with complexing factors like citric acid and EDTA significantly stimulated the growth rate and chlorophyll a production. The citric acid - EDTA - Fe (5 × 10-7 mol dm-3 complex was demonstrably effective in stimulating the rate of cell division. Starting with 10-6 mol dm-3, the higher the iron(III concentration used in the media, the more intensive the growth of the cyanobacteria populations. This was most rapid in the presence of high iron concentrations (10-4 mol dm-3, regardless of the presence of complexing agents.     It appears that the growth of toxic cyanobacteria N. spumigena, and thus also its ability to form blooms, may well depend on iron availability in the environment.

  17. Factors limiting heterotrophic bacterial production in the southern Pacific Ocean

    Directory of Open Access Journals (Sweden)

    F. Van Wambeke

    2007-10-01

    Full Text Available The role of potential factors limiting bacterial growth was investigated along vertical and longitudinal gradients across the South Eastern Pacific Gyre. The effects of glucose, nitrate, ammonium and phosphate additions on heterotrophic bacterial production (using leucine technique were studied in parallel in unfiltered seawater samples incubated under natural daily irradiance. Longitudinally, the enrichments realized on the subsurface showed three types of responses. From the Marquesas plateau (8° W to approx 125° W, bacteria were not bottom-up controlled, as confirmed by the huge potential of growth in non-enriched seawater (43±24 times in 24 h. Within the Gyre (125° W–95° W, nitrogen alone stimulated leucine incorporation rates by a factor of 5.6±3.6, but rapidly labile carbon (glucose became a second limiting factor (enhancement factor 49±32 when the two elements were added. Finally from the border of the gyre to the Chilean upwelling (95° W–73° W, labile carbon was the only factor stimulating heterotrophic bacterial production. Interaction between phytoplankton and heterotrophic bacterial communities and the direct versus indirect effect of iron and macronutrients on bacterial production were also investigated in four selected sites: two sites on the vicinity of the Marquesas plateau, the centre of the gyre and the Eastern border of the gyre. Both phytoplankton and heterotrophic bacteria were limited by availability of nitrogen within the gyre, but not by iron. While iron limited phytoplankton at Marquesas plateau and at the eastern border of the gyre, heterotrophic bacteria were only limited by availability of labile DOC in those environments.

  18. Growth Factor Mediated Signaling in Pancreatic Pathogenesis

    Energy Technology Data Exchange (ETDEWEB)

    Nandy, Debashis; Mukhopadhyay, Debabrata, E-mail: mukhopadhyay.debabrata@mayo.edu [Department of Biochemistry and Molecular Biology, College of Medicine, Mayo Clinic, 200 First Street SW, Guggenheim 1321C, Rochester, MN 55905 (United States)

    2011-02-24

    Functionally, the pancreas consists of two types of tissues: exocrine and endocrine. Exocrine pancreatic disorders mainly involve acute and chronic pancreatitis. Acute pancreatitis typically is benign, while chronic pancreatitis is considered a risk factor for developing pancreatic cancer. Pancreatic carcinoma is the fourth leading cause of cancer related deaths worldwide. Most pancreatic cancers develop in the exocrine tissues. Endocrine pancreatic tumors are more uncommon, and typically are less aggressive than exocrine tumors. However, the endocrine pancreatic disorder, diabetes, is a dominant cause of morbidity and mortality. Importantly, different growth factors and their receptors play critical roles in pancreatic pathogenesis. Hence, an improved understanding of how various growth factors affect pancreatitis and pancreatic carcinoma is necessary to determine appropriate treatment. This chapter describes the role of different growth factors such as vascular endothelial growth factor (VEGF), insulin-like growth factor (IGF), platelet derived growth factor (PDGF), fibroblast growth factor (FGF), epidermal growth factor (EGF), and transforming growth factor (TGF) in various pancreatic pathophysiologies. Finally, the crosstalk between different growth factor axes and their respective signaling mechanisms, which are involved in pancreatitis and pancreatic carcinoma, are also discussed.

  19. Growth Factor Mediated Signaling in Pancreatic Pathogenesis

    Directory of Open Access Journals (Sweden)

    Debashis Nandy

    2011-02-01

    Full Text Available Functionally, the pancreas consists of two types of tissues: exocrine and endocrine. Exocrine pancreatic disorders mainly involve acute and chronic pancreatitis. Acute pancreatitis typically is benign, while chronic pancreatitis is considered a risk factor for developing pancreatic cancer. Pancreatic carcinoma is the fourth leading cause of cancer related deaths worldwide. Most pancreatic cancers develop in the exocrine tissues. Endocrine pancreatic tumors are more uncommon, and typically are less aggressive than exocrine tumors. However, the endocrine pancreatic disorder, diabetes, is a dominant cause of morbidity and mortality. Importantly, different growth factors and their receptors play critical roles in pancreatic pathogenesis. Hence, an improved understanding of how various growth factors affect pancreatitis and pancreatic carcinoma is necessary to determine appropriate treatment. This chapter describes the role of different growth factors such as vascular endothelial growth factor (VEGF, insulin-like growth factor (IGF, platelet derived growth factor (PDGF, fibroblast growth factor (FGF, epidermal growth factor (EGF, and transforming growth factor (TGF in various pancreatic pathophysiologies. Finally, the crosstalk between different growth factor axes and their respective signaling mechanisms, which are involved in pancreatitis and pancreatic carcinoma, are also discussed.

  20. Transforming growth factor alpha, Shope fibroma growth factor, and vaccinia growth factor can replace myxoma growth factor in the induction of myxomatosis in rabbits.

    Science.gov (United States)

    Opgenorth, A; Nation, N; Graham, K; McFadden, G

    1993-02-01

    The epidermal growth factor (EGF) homologues encoded by vaccinia virus, myxoma virus, and malignant rabbit fibroma virus have been shown to contribute to the pathogenicity of virus infection upon inoculation of susceptible hosts. However, since the primary structures of these growth factors and the disease profiles induced by different poxvirus genera vary substantially, the degree to which the various EGF homologues perform similar roles in viral pathogenesis remains unclear. In order to determine whether different EGF-like growth factors can perform qualitatively similar functions in the induction of myxomatosis in rabbits, we created recombinant myxoma virus variants in which the native growth factor, myxoma growth factor (MGF), was disrupted and replaced with either vaccinia virus growth factor, Shope fibroma growth factor, or rat transforming growth factor alpha. Unlike the control virus containing an inactivated MGF gene, which caused marked attenuation of the disease syndrome and substantially less proliferation of the epithelial cell layers in the conjunctiva and respiratory tract, the recombinant myxoma virus strains expressing heterologous growth factors produced infections which were both clinically and histopathologically indistinguishable from wild-type myxomatosis. We conclude that these poxviral and cellular EGF-like growth factors, which are diverse with respect to primary structure and origin, have similar biological functions in the context of myxoma virus pathogenesis and are mitogenic for the same target cells.

  1. Dependence of Limited Growth Rate of High-Quality Gem Diamond on Growth Conditions

    Institute of Scientific and Technical Information of China (English)

    TIAN Yu; MA Hong-An; LI Shang-Sheng; XIAO Hong-Yu; ZHANG Ya-Fei; HUANG Guo-Feng; MA Li-Qiu; JIA Xiao-Peng

    2007-01-01

    The growth rate of diamond has been investigated for a long time and researchers have been attempting to enhance the growth rate of high-quality gem diamond infinitely. However, it has been found according to previous research results that the quality of diamond is debased with the increase of growth rate. Thus, under specific conditions, the growth rate of high-quality diamond cannot exceed a limited value that is called the limited growth rate of diamond. We synthesize a series of type Ib gem diamonds by temperature gradient method under high pressure and high temperature (HPHT) using the as-grown {100} face. The dependence of limited growth rate on growth conditions is studied. The results show that the limited growth rate increases when synthetic temperature decreases, also when growth time is prolonged.

  2. Fibroblast growth factors in neurodevelopment and psychopathology

    NARCIS (Netherlands)

    Terwisscha van Scheltinga, Afke F; Bakker, Steven C; Kahn, René S; Kas, Martien J H

    2013-01-01

    In psychiatric disorders, the effect of genetic and environmental factors may converge on molecular pathways and brain circuits related to growth factor functioning. In this review, we describe how disturbances in fibroblast growth factors (FGFs) and their receptors influence behavior by affecting b

  3. Growth factors and acute renal failure.

    Science.gov (United States)

    Hirschberg, R; Ding, H

    1998-03-01

    During acute renal injury, there are alterations in the expression of several growth factors and their receptors in the kidney. The increased expression of several growth factors and/or their receptors at sites of nephron injury suggests important contributions to repair. Exogenous administration of some growth factors, such as IGF-I, EGF and HGF, accelerates recovery of renal function in experimental acute renal failure (ARF). In ARF growth factors act through several mechanisms, which may include altered cell cycle regulation and mitogenesis, differentiation of recovered cells, regulation of apoptosis, improved renal hemodynamics, and others. There is evidence for interactions of growth factors with other growth factors as well as with other genes resulting in complex orchestration of biologic events contributing to recovery from ARF.

  4. Synthetic heparin-binding growth factor analogs

    Science.gov (United States)

    Pena, Louis A.; Zamora, Paul; Lin, Xinhua; Glass, John D.

    2007-01-23

    The invention provides synthetic heparin-binding growth factor analogs having at least one peptide chain that binds a heparin-binding growth factor receptor, covalently bound to a hydrophobic linker, which is in turn covalently bound to a non-signaling peptide that includes a heparin-binding domain. The synthetic heparin-binding growth factor analogs are useful as soluble biologics or as surface coatings for medical devices.

  5. Epidermal growth factor and insulin-like growth factor I upregulate the expression of the epidermal growth factor system in rat liver

    DEFF Research Database (Denmark)

    Bor, M V; Sørensen, B S; Vinter-Jensen, L

    2000-01-01

    as the expression of transforming growth factor-alpha peptide. The level of epidermal growth factor receptor and transforming growth factor-alpha mRNA expression was found to correlate both in control and growth factor-treated animals, whereas the expression of epidermal growth factor receptor and epidermal growth...

  6. Factors enhancing L-valine production by the growth-limited L-isoleucine auxotrophic strain Corynebacterium glutamicum DeltailvA DeltapanB ilvNM13 (pECKAilvBNC).

    Science.gov (United States)

    Denina, Ilze; Paegle, Longina; Prouza, Marek; Holátko, Jiri; Pátek, Miroslav; Nesvera, Jan; Ruklisha, Maija

    2010-07-01

    Cell growth limitation is known to be an important condition that enhances L: -valine synthesis in Corynebacterium glutamicum recombinant strains with L: -isoleucine auxotrophy. To identify whether it is the limited availability of L: -isoleucine itself or the L: -isoleucine limitation-induced rel-dependent ppGpp-mediated stringent response that is essential for the enhancement of L: -valine synthesis in growth-limited C. glutamicum cells, we deleted the rel gene, thereby constructing a relaxed (rel (-) ) C. glutamicum DeltailvA DeltapanB Deltarel ilvNM13 (pECKAilvBNC) strain. Variations in enzyme activity and L: -valine synthesis in rel (+) and rel (-) strains under conditions of L: -isoleucine excess and limitation were investigated. A sharp increase in acetohydroxy acid synthase (AHAS) activity, a slight increase in acetohydroxyacid isomeroreductase (AHAIR) activity, and a dramatic increase in L: -valine synthesis were observed in both rel (+) and rel (-) cells exposed to L: -isoleucine limitation. Although the positive effect of induction of the stringent response on AHAS and AHAIR upregulation in cells was not confirmed, we found the stringent response to be beneficial for maintaining increased AHAS, dihydroxyacid dehydratase, and transaminase B activity and L: -valine synthesis in cells during the stationary growth phase.

  7. Co-limitation of potato growth by Potato Cyst Nematode (Globodera rostochiensis) and Rhizoctonia solani

    NARCIS (Netherlands)

    Kiani, Z.; Zafari, D.; Rezaee, S.; Arjmandian, A.; Gitti, M.; Struik, P.C.

    2013-01-01

    Globodera rostochiensis and Rhizoctonia solani are the most important growth limiting factors influencing potato production in Iran. The effects of inoculation with Potato Cyst Nematodes (PCN) (0, 50, 75 and 100 cysts/3.5 kg soil) and R. solani (with or without inoculation) on potato growth and deve

  8. Growth factor involvement in tension-induced skeletal muscle growth

    Science.gov (United States)

    Vandenburgh, Herman H.

    1993-01-01

    Long-term manned space travel will require a better understanding of skeletal muscle atrophy which results from microgravity. Astronaut strength and dexterity must be maintained for normal mission operations and for emergency situations. Although exercise in space slows the rate of muscle loss, it does not prevent it. A biochemical understanding of how gravity/tension/exercise help to maintain muscle size by altering protein synthesis and/or degradation rate should ultimately allow pharmacological intervention to prevent muscle atrophy in microgravity. The overall objective is to examine some of the basic biochemical processes involved in tension-induced muscle growth. With an experimental in vitro system, the role of exogenous and endogenous muscle growth factors in mechanically stimulated muscle growth are examined. Differentiated avian skeletal myofibers can be 'exercised' in tissue culture using a newly developed dynamic mechanical cell stimulator device which simulates different muscle activity patterns. Patterns of mechanical activity which significantly affect muscle growth and metabolic characteristics were found. Both exogenous and endogenous growth factors are essential for tension-induced muscle growth. Exogenous growth factors found in serum, such as insulin, insulin-like growth factors, and steroids, are important regulators of muscle protein turnover rates and mechanically-induced muscle growth. Endogenous growth factors are synthesized and released into the culture medium when muscle cells are mechanically stimulated. At least one family of mechanically induced endogenous factors, the prostaglandins, help to regulate the rates of protein turnover in muscle cells. Endogenously synthesized IGF-1 is another. The interaction of muscle mechanical activity and these growth factors in the regulation of muscle protein turnover rates with our in vitro model system is studied.

  9. Transcription factor control of growth rate dependent genes in Saccharomyces cerevisiae: A three factor design

    DEFF Research Database (Denmark)

    Fazio, Alessandro; Jewett, Michael Christopher; Daran-Lapujade, Pascale;

    2008-01-01

    Background: Characterization of cellular growth is central to understanding living systems. Here, we applied a three-factor design to study the relationship between specific growth rate and genome-wide gene expression in 36 steady-state chemostat cultures of Saccharomyces cerevisiae. The three...... factors we considered were specific growth rate, nutrient limitation, and oxygen availability. Results: We identified 268 growth rate dependent genes, independent of nutrient limitation and oxygen availability. The transcriptional response was used to identify key areas in metabolism around which m...... transcription factor target sets, transcription factors that coordinate balanced growth were also identified. Our analysis shows that FhII, Rap1, and Sfp1, regulating protein biosynthesis, have significantly enriched target sets for genes up-regulated with increasing growth rate. Cell cycle regulators...

  10. Response to epidermal growth factor receptor inhibitors in non-small cell lung cancer cells : Limited antiproliferative effects and absence of apoptosis associated with persistent activity of extracellular signal-regulated kinase or Akt kinase pathways

    NARCIS (Netherlands)

    Janmaat, ML; Kruyt, FAE; Rodriguez, JA; Giaccone, G

    2003-01-01

    The epidermal growth factor receptor (EGFR) is an important novel target for anticancer therapy. In this study, we examined the molecular mechanisms that underlie the antitumor effects of the anti-EGFR monoclonal antibody C225 (Cetuximab) and the selective EGFR tyrosine kinase inhibitor ZD1839 (Ires

  11. Transforming growth factor alpha and epidermal growth factor in laryngeal carcinomas demonstrated by immunohistochemistry

    DEFF Research Database (Denmark)

    Christensen, M E; Therkildsen, M H; Poulsen, Steen Seier

    1993-01-01

    Fifteen laryngeal squamous cell carcinomas were investigated for the presence of transforming growth factor alpha (TGF-alpha) and epidermal growth factor (EGF) using immunohistochemical methods. In a recent study the same material was characterized for epidermal growth factor receptors (EGF recep...

  12. Growth Factors for the Treatment of Ischemic Brain Injury (Growth Factor Treatment

    Directory of Open Access Journals (Sweden)

    Amara Larpthaveesarp

    2015-04-01

    Full Text Available In recent years, growth factor therapy has emerged as a potential treatment for ischemic brain injury. The efficacy of therapies that either directly introduce or stimulate local production of growth factors and their receptors in damaged brain tissue has been tested in a multitude of models for different Central Nervous System (CNS diseases. These growth factors include erythropoietin (EPO, vascular endothelial growth factor (VEGF, brain-derived neurotrophic factor (BDNF, and insulin-like growth factor (IGF-1, among others. Despite the promise shown in animal models, the particular growth factors that should be used to maximize both brain protection and repair, and the therapeutic critical period, are not well defined. We will review current pre-clinical and clinical evidence for growth factor therapies in treating different causes of brain injury, as well as issues to be addressed prior to application in humans.

  13. Growth factors for the treatment of ischemic brain injury (growth factor treatment).

    Science.gov (United States)

    Larpthaveesarp, Amara; Ferriero, Donna M; Gonzalez, Fernando F

    2015-04-30

    In recent years, growth factor therapy has emerged as a potential treatment for ischemic brain injury. The efficacy of therapies that either directly introduce or stimulate local production of growth factors and their receptors in damaged brain tissue has been tested in a multitude of models for different Central Nervous System (CNS) diseases. These growth factors include erythropoietin (EPO), vascular endothelial growth factor (VEGF), brain-derived neurotrophic factor (BDNF), and insulin-like growth factor (IGF-1), among others. Despite the promise shown in animal models, the particular growth factors that should be used to maximize both brain protection and repair, and the therapeutic critical period, are not well defined. We will review current pre-clinical and clinical evidence for growth factor therapies in treating different causes of brain injury, as well as issues to be addressed prior to application in humans.

  14. Growth factors for treating diabetic foot ulcers

    DEFF Research Database (Denmark)

    Martí-Carvajal, Arturo J; Gluud, Christian; Nicola, Susana

    2015-01-01

    with a foot ulcer. Trials were eligible for inclusion if they compared a growth factor plus standard care (e.g., antibiotic therapy, debridement, wound dressings) versus placebo or no growth factor plus standard care, or compared different growth factors against each other. We considered lower limb amputation......, vascular, or combined) was poorly defined in all trials. The trials were conducted in ten countries. The trials assessed 11 growth factors in 30 comparisons: platelet-derived wound healing formula, autologous growth factor, allogeneic platelet-derived growth factor, transforming growth factor β2, arginine...... with complete wound healing (345/657 (52.51%) versus 167/482 (34.64%); RR 1.51, 95% CI 1.31 to 1.73; I(2) = 51%, 12 trials; low quality evidence). The result is mainly based on platelet-derived wound healing formula (36/56 (64.28%) versus 7/27 (25.92%); RR 2.45, 95% 1.27 to 4.74; I(2) = 0%, two trials...

  15. Autologous growth factor injections in chronic tendinopathy.

    Science.gov (United States)

    Sandrey, Michelle A

    2014-01-01

    de Vos RJ, van Veldhoven PLJ, Moen MH, Weir A, Tol JL. Autologous growth factor injections in chronic tendinopathy: a systematic review. Br Med Bull. 2010;95:63-77. The authors of this systematic review evaluated the literature to critically consider the effects of growth factors delivered through autologous whole-blood and platelet-rich-plasma (PRP) injections in managing wrist-flexor and -extensor tendinopathies, plantar fasciopathy, and patellar tendinopathy. The primary question was, according to the published literature, is there sufficient evidence to support the use of growth factors delivered through autologous whole-blood and PRP injections for chronic tendinopathy? The authors performed a comprehensive, systematic literature search in October 2009 using PubMed, MEDLINE, EMBASE, CINAHL, and the Cochrane library without time limits. The following key words were used in different combinations: tendinopathy, tendinosis, tendinitis, tendons, tennis elbow, plantar fasciitis, platelet rich plasma, platelet transfusion, and autologous blood or injection. The search was limited to human studies in English. All bibliographies from the initial literature search were also viewed to identify additional relevant studies. Studies were eligible based on the following criteria: (1) Articles were suitable (inclusion criteria) if the participants had been clinically diagnosed as having chronic tendinopathy; (2) the design had to be a prospective clinical study, randomized controlled trial, nonrandomized clinical trial, or prospective case series; (3) a well-described intervention in the form of a growth factor injection with either PRP or autologous whole blood was used; and (4) the outcome was reported in terms of pain or function (or both). All titles and abstracts were assessed by 2 researchers, and all relevant articles were obtained. Two researchers independently read the full text of each article to determine if it met the inclusion criteria. If opinions differed on

  16. Limiting Shapes for Deterministic Centrally Seeded Growth Models

    NARCIS (Netherlands)

    Fey-den Boer, Anne; Redig, Frank

    2007-01-01

    We study the rotor router model and two deterministic sandpile models. For the rotor router model in ℤ d , Levine and Peres proved that the limiting shape of the growth cluster is a sphere. For the other two models, only bounds in dimension 2 are known. A unified approach for these models with a

  17. Limiting Shapes for Deterministic Centrally Seeded Growth Models

    NARCIS (Netherlands)

    Fey-den Boer, Anne; Redig, Frank

    2007-01-01

    We study the rotor router model and two deterministic sandpile models. For the rotor router model in ℤ d , Levine and Peres proved that the limiting shape of the growth cluster is a sphere. For the other two models, only bounds in dimension 2 are known. A unified approach for these models with a

  18. The growth limits of the low cost carrier model

    NARCIS (Netherlands)

    de Wit, J.G.; Zuidberg, J.

    2012-01-01

    Today, many low cost carriers (LCCs) continue to enjoy rapid growth and still have a fair number of new aircraft on order. There are signs however that the market for LCCs is limited, owing to increasing route density problems, primarily in Europe but seemingly also in North America: the fact that a

  19. Stability limits for the horizontal ribbon growth of silicon crystals

    Science.gov (United States)

    Daggolu, Parthiv; Yeckel, Andrew; Bleil, Carl E.; Derby, Jeffrey J.

    2013-01-01

    A rigorous, thermal-capillary model, developed to couple heat transfer, melt convection and capillary physics, is employed to assess stability limits of the HRG system for growing silicon ribbons. Extending the prior understanding of this process put forth by Daggolu et al. [Thermal-capillary analysis of the horizontal ribbon growth of silicon crystals, Journal of Crystal Growth 355 (2012) 129-139], model results presented here identify additional failure mechanisms, including the bridging of crystal onto crucible, the spilling of melt from the crucible, and the undercooling of melt at the ribbon tip, that are consistent with prior experimental observations. Changes in pull rate, pull angle, melt height, and other parameters are shown to give rise to limits, indicating that only narrow operating windows exist in multi-dimensional parameter space for stable growth conditions that circumvent these failure mechanisms.

  20. Family Factors in Small Family Business Growth

    National Research Council Canada - National Science Library

    Jim Cater; Marilyn Young

    2016-01-01

    .... We suggest that while all three patterns of small family business growth may lead to individual company success and sustainability, businesses with units in multiple trade areas may be most adept at managing the six family factors.

  1. Placental growth factor and vascular endothelial growth factor receptor-2 in human lung development.

    Science.gov (United States)

    Janér, Joakim; Andersson, Sture; Haglund, Caj; Karikoski, Riitta; Lassus, Patrik

    2008-08-01

    We examined the pulmonary expression of 2 proangiogenic factors, namely, placental growth factor and vascular endothelial growth factor receptor-2, during lung development and acute and chronic lung injury in newborn infants. Six groups were included in an immunohistochemical study of placental growth factor and vascular endothelial growth factor receptor-2, that is, 9 fetuses, 4 preterm and 8 term infants without lung injury who died soon after birth, 5 preterm infants with respiratory distress syndrome of 10 days, and 6 with bronchopulmonary dysplasia. Placental growth factor concentrations in tracheal aspirate fluid were measured in 70 samples from 20 preterm infants during the first postnatal week. In immunohistochemical analyses, placental growth factor staining was seen in bronchial epithelium and macrophages in all groups. Distal airway epithelium positivity was observed mostly in fetuses and in preterm infants who died soon after birth. Vascular endothelial growth factor receptor-2 staining was seen in vascular endothelium in all groups and also in lymphatic endothelium in fetuses. Vascular endothelial growth factor receptor-2 staining in arterial endothelium was associated with higher and staining in venous endothelium with lower gestational age. In capillaries, less vascular endothelial growth factor receptor-2 staining was seen in bronchopulmonary dysplasia. The mean placental growth factor protein concentration in tracheal aspirate fluid during the first postnatal week was 0.64 +/- 0.42 pg/mL per IgA-secretory component unit. Concentrations during the first postnatal week were stable. Lower placental growth factor concentrations correlated with chorioamnionitis and lactosyl ceramide positivity. The vascular endothelial growth factor receptor-2 staining pattern seems to reflect ongoing differentiation and activity of different endothelia. Lower vascular endothelial growth factor receptor-2 expression in capillary endothelium in bronchopulmonary dysplasia

  2. Epidermal growth factor in the rat prostate

    DEFF Research Database (Denmark)

    Tørring, Niels; Jørgensen, P E; Poulsen, Steen Seier;

    1998-01-01

    Epidermal growth factor (EGF) induces proliferation in prostate epithelial and stromal cells in primary culture. This investigation was set up to characterize the time and spatial expression of EGF in the rat prostate.......Epidermal growth factor (EGF) induces proliferation in prostate epithelial and stromal cells in primary culture. This investigation was set up to characterize the time and spatial expression of EGF in the rat prostate....

  3. Limiting factors for reforestation of mine spoils from Galicia (Spain)

    Energy Technology Data Exchange (ETDEWEB)

    Vega, F.A.; Covelo, E.F.; Andrade, M.L. [University of Vigo, Vigo (Spain)

    2005-02-01

    Mined areas are a continuing source of heavy metals and acidity that move off site in response to erosion. Revegetation of the mine tailings could limit the spread of these heavy metals and acidity. This study was conducted to evaluate, at four tailings on opencast mines of Galicia (Touro: copper mine; and Meirama: lignite mine, NW Spain), the chemical and physical soil quality indicators and limiting edaphic factors concerning forest production. Selected zones were: (1) The tailings formed by the waste materials from the depleted Touro mine; (2) the decantation site of deposited sludge coming from the copper extraction in the flotation stage; (3) and (4) tailings of 3 and 10 years old of the Meirama lignite mine. The main physical limitations of the mine soils are the low effective depth ({lt} 50cm), high stoniness ({gt} 30 percent) and high porosity ({gt} 60 percent); which make them vulnerable to soil erosion and seriously interferes with the forest production. Soils coming from the decantation site of copper mine do not have physical limitations. The main chemical limitations of mine soils are their acidity (pH from 3.62 to 5.71), and aluminium saturation ({gt} 60 per cent in copper mine soils, and {gt} 20 per cent in lignite mine soils), low CECe (from 5.34 to 9.47 cmol{sub +}) kg{sup -1}), organic carbon (from 0.47 to 7.52 mg kg{sup -1}) and Ca{sup 2+} and Mg{sup 2+} contents, and imbalance between exchange bases. Lime and organic amendments are the most important factors in providing a suitable medium for plant growth.

  4. Insulin-like growth factor 1 and hair growth.

    Science.gov (United States)

    Su, H Y; Hickford, J G; Bickerstaffe, R; Palmer, B R

    1999-11-01

    Insulin-like growth factor 1 (IGF-1) has been identified as an important growth factor in many biological systems.[1] It shares considerable structural homology with insulin and exerts insulin-like effects on food intake and glucose metabolism. Recently it has been suggested to play a role in regulating cellular proliferation and migration during the development of hair follicles. [2,3] To exert its biological effects, the IGF-1 is required to activate cells by binding to specific cell-surface receptors. The type I IGF receptor (IGF-1R) is the only IGF receptor to have IGF-mediated signaling functions.[1] In circulation, this growth factor mediates endocrine action of growth hormone (GH) on somatic growth and is bound to specific binding proteins (BPs). The latter control IGF transport, efflux from vascular compartments and association with cell surface receptors.[4] In tissues, IGF-1 is produced by mesenchymal type cells and acts in a paracrine and autocrine fashion by binding to the IGF-1R. This binding activates the receptor tyrosine kinase (RTK) that triggers the downstream responses and finally stimulates cell division.[5] IGF-1 may therefore be able to stimulate the proliferation of hair follicle cells through cellular signaling pathways of its receptors. Local infusion of IGF-1 into sheep has been reported to be capable of stimulating protein synthesis in the skin.[6] It may also increase the production of wool keratin. Recently, transgenic mice overexpressing IGF-1 in the skin have been shown to have earlier hair follicle development than controls.[7] In addition, this growth factor plays an important role in many cell types as a survival factor to prevent cell death.[8] This anti-apoptotic function of IGF-1 may be important to the development of follicle cells as follicles undergo a growth cycle where the regressive, catagen phase is apoptosis driven. In this review, the effects of IGF-1 on follicle cell proliferation and differentiation are discussed. In

  5. Winter climate limits subantarctic low forest growth and establishment.

    Science.gov (United States)

    Harsch, Melanie A; McGlone, Matt S; Wilmshurst, Janet M

    2014-01-01

    Campbell Island, an isolated island 600 km south of New Zealand mainland (52 °S, 169 °E) is oceanic (Conrad Index of Continentality  =  -5) with small differences between mean summer and winter temperatures. Previous work established the unexpected result that a mean annual climate warming of c. 0.6 °C since the 1940's has not led to upward movement of the forest limit. Here we explore the relative importance of summer and winter climatic conditions on growth and age-class structure of the treeline forming species, Dracophyllum longifolium and Dracophyllum scoparium over the second half of the 20th century. The relationship between climate and growth and establishment were evaluated using standard dendroecological methods and local climate data from a meteorological station on the island. Growth and establishment were correlated against climate variables and further evaluated within hierarchical regression models to take into account the effect of plot level variables. Winter climatic conditions exerted a greater effect on growth and establishment than summer climatic conditions. Establishment is maximized under warm (mean winter temperatures >7 °C), dry winters (total winter precipitation <400 mm). Growth, on the other hand, is adversely affected by wide winter temperature ranges and increased rainfall. The contrasting effect of winter warmth on growth and establishment suggests that winter temperature affects growth and establishment through differing mechanisms. We propose that milder winters enhance survival of seedlings and, therefore, recruitment, but increases metabolic stress on established plants, resulting in lower growth rates. Future winter warming may therefore have complex effects on plant growth and establishment globally.

  6. Winter climate limits subantarctic low forest growth and establishment.

    Directory of Open Access Journals (Sweden)

    Melanie A Harsch

    Full Text Available Campbell Island, an isolated island 600 km south of New Zealand mainland (52 °S, 169 °E is oceanic (Conrad Index of Continentality  =  -5 with small differences between mean summer and winter temperatures. Previous work established the unexpected result that a mean annual climate warming of c. 0.6 °C since the 1940's has not led to upward movement of the forest limit. Here we explore the relative importance of summer and winter climatic conditions on growth and age-class structure of the treeline forming species, Dracophyllum longifolium and Dracophyllum scoparium over the second half of the 20th century. The relationship between climate and growth and establishment were evaluated using standard dendroecological methods and local climate data from a meteorological station on the island. Growth and establishment were correlated against climate variables and further evaluated within hierarchical regression models to take into account the effect of plot level variables. Winter climatic conditions exerted a greater effect on growth and establishment than summer climatic conditions. Establishment is maximized under warm (mean winter temperatures >7 °C, dry winters (total winter precipitation <400 mm. Growth, on the other hand, is adversely affected by wide winter temperature ranges and increased rainfall. The contrasting effect of winter warmth on growth and establishment suggests that winter temperature affects growth and establishment through differing mechanisms. We propose that milder winters enhance survival of seedlings and, therefore, recruitment, but increases metabolic stress on established plants, resulting in lower growth rates. Future winter warming may therefore have complex effects on plant growth and establishment globally.

  7. Organic growth factor requirements of some yeasts.

    Science.gov (United States)

    Madan, M; Gulati, N

    1980-01-01

    Some sporogenous yeasts (Brettanomyces bruxellensis, Debaryomyces hansenii, Hansenula ciferrii, Hansenula polymorpha, Pichia polymorpha, Saccharomycopsis guttulata, and Saccharomyces chevalieri), isolated from various fruits have been examined for their organic growth factor requisites. H. ciferrii was completely deficient in thiamine, biotin, inositol, riboflavin, niacin, and partially deficient in pantothenic acid. It required an external supply of 0.1-1.0 ppm thiamine, 0.01-0.1 ppm biotin, 10.0 ppm inositol, 0.10 ppm niacin and riboflavin for its optimum growth. H. polymorpha showed partial deficiency only in xanthine. P. polymorpha gave indications of partial deficiencies in thiamine and biotin. S. guttulata was completely deficient in biotin, and partially deficient in adenine sulphate. It required 0.01 ppm biotin for optimum growth. S chevalieri was completely deficient in pyridoxine and partially deficient in thiamine. It required 0.1 ppm pyridoxine for maximum growth. D. hansenii and B bruxellensis were auxoautotrophic for the various growth factors studied.

  8. Therapeutic modulation of growth factors and cytokines in regenerative medicine.

    Science.gov (United States)

    Ioannidou, Effie

    2006-01-01

    Regeneration that takes place in the human body is limited throughout life. Therefore, when organs are irreparably damaged, they are usually replaced with an artificial device or donor organ. The term "regenerative medicine" covers the restoration or replacement of cells, tissues, and organs. Stem cells play a major role in regenerative medicine by providing the way to repopulate organs damaged by disease. Stem cells have the ability to self renew and to regenerate cells of diverse lineages within the tissue in which they reside. Stem cells could originate from embryos or adult tissues. Growth factors are proteins that may act locally or systemically to affect the growth of cells in several ways. Various cell activities, including division, are influenced by growth factors. Cytokines are a family of low-molecular-weight proteins that are produced by numerous cell types and are responsible for regulating the immune response, inflammation, tissue remodeling and cellular differentiation. Target cells of growth factors and cytokines are mesenchymal, epithelial and endothelial cells. These molecules frequently have overlapping activities and can act in an autocrine or paracrine fashion. A complex network of growth factors and cytokines guides cellular differentiation and regeneration in all organs and tissues. The aim of this paper is to review the role of growth factors and cytokines in different organs or systems and explore their therapeutic application in regenerative medicine. The role of stem cells combined with growth factors and cytokines in the regeneration of vascular and hematopoietic, neural, skeletal, pancreatic, periodontal, and mucosal tissue is reviewed. There is evidence that supports the use of growth factors and cytokines in the treatment of neurological diseases, diabetes, cardiovascular disease, periodontal disease, cancer and its complication, oral mucositis. After solving the ethical issues and establishing clear and reasonable regulations

  9. Physiological requirements for growth and competitiveness of Dekkera bruxellensis under oxygen-limited or anaerobic conditions.

    Science.gov (United States)

    Blomqvist, Johanna; Nogué, Violeta Sànchez; Gorwa-Grauslund, Marie; Passoth, Volkmar

    2012-07-01

    The effect of glucose and oxygen limitation on the growth and fermentation performances of Dekkera bruxellensis was investigated in order to understand which factors favour its propagation in ethanol or wine plants. Although D. bruxellensis has been described as a facultative anaerobe, no growth was observed in mineral medium under complete anaerobiosis while growth was retarded under severe oxygen limitation. In a continuous culture with no gas inflow, glucose was not completely consumed, most probably due to oxygen limitation. When an air/nitrogen mixture (O(2)-content ca. 5%) was sparged to the culture, growth became glucose-limited. In co-cultivations with Saccharomyces cerevisiae, ethanol yields/g consumed sugar were not affected by the co-cultures as compared to the pure cultures. However, different population responses were observed in both systems. In oxygen-limited cultivation, glucose was depleted within 24 h after challenging with S. cerevisiae and both yeast populations were maintained at a stable level. In contrast, the S. cerevisiae population constantly decreased to about 1% of its initial cell number in the sparged glucose-limited fermentation, whereas the D. bruxellensis population remained constant. To identify the requirements of D. bruxellensis for anaerobic growth, the yeast was cultivated in several nitrogen sources and with the addition of amino acids. Yeast extract and most of the supplied amino acids supported anaerobic growth, which points towards a higher nutrient demand for D. bruxellensis compared to S. cerevisiae in anaerobic conditions. Copyright © 2012 John Wiley & Sons, Ltd.

  10. Growth limit of carbon onions – A continuum mechanical study

    DEFF Research Database (Denmark)

    Todt, Melanie; Bitsche, Robert; Hartmann, Markus A.

    2014-01-01

    The growth of carbon onions is simulated using continuum mechanical shell models. With this models it is shown that, if a carbon onion has grown to a critical size, the formation of an additional layer leads to the occurrence of a structural instability. This instability inhibits further growth...... of carbon onions and, thus, can be a reason for the limited size of such particles. The loss of stability is mainly evoked by van der Waals interactions between misfitting neighboring layers leading to self-equilibrating stress states in the layers due to mutual accommodation. The influence of the curvature...... model gives insight into mechanisms which are assumed to limit the size of carbon onions and can serve as basis for further investigations, e.g., of the formation of nanodiamonds in the center of carbon onions. © 2013 Elsevier Ltd. All rights reserved....

  11. Once again about "The Limits to Growth" (in Russian)

    DEFF Research Database (Denmark)

    Nørgaard, Jørgen; Tarasova, Natalia P.; Mustafin, D. I.

    2009-01-01

    The paper analyses the critics of the pioneering and best selling report "The Limits to Growth" from 1972 by D. Meadows et.al., which outlined future global development options, with respect to population, resource depletion, food production, pollution, etc. In the paper is observed that nothing....... Actually the report seems to be surprisingly right in its agregated analyses of future options, and in the present recognition of climtate change it would be wise to learn from the report and its updating version....

  12. Factors that determine the evolution of high-growth businesses

    Directory of Open Access Journals (Sweden)

    Oriol Amat

    2013-09-01

    Full Text Available Objective: The study herein discusses research aimed at elucidating the factors that contribute to a business’ ability to maintain high growth. Design/Methodology/Perspective: The database from the Iberian Balance Sheet Analysis System (SABI, from its initials in Spanish was used to identify 250 industrial Catalonian businesses with high growth during 2004-2007. These companies participated in a survey on strategies and management practices; in 2013, they were re-analyzed to investigate the factors that contributed to continued growth for certain companies. Contributions: Through diverse statistical techniques, business policies related to quality, innovation, internationalization and finance were shown to influence business growth and sustainability over time. Limitations of the Research: This study focuses on industrial businesses at least ten years old in Catalonia; thus, the conclusions may differ in other geographic locations and economic sectors, as well as for smaller businesses. Practical Implications: Because growth is a measure of business success, identifying variables that contribute to high growth and its sustainability is helpful for businesses that seek to adopt effective policies. Social Implications: Generating employment is one of the primary contributions by high-growth businesses. For years with high unemployment, authorities may be interested in corporate policies that strengthen high-growth businesses. Originality/Added Value: High-growth businesses have been studied throughout the world, but this is the first study to investigate the evolution of businesses after a high-growth phase.

  13. Metabolic factors limiting performance in marathon runners.

    Directory of Open Access Journals (Sweden)

    Benjamin I Rapoport

    Full Text Available Each year in the past three decades has seen hundreds of thousands of runners register to run a major marathon. Of those who attempt to race over the marathon distance of 26 miles and 385 yards (42.195 kilometers, more than two-fifths experience severe and performance-limiting depletion of physiologic carbohydrate reserves (a phenomenon known as 'hitting the wall', and thousands drop out before reaching the finish lines (approximately 1-2% of those who start. Analyses of endurance physiology have often either used coarse approximations to suggest that human glycogen reserves are insufficient to fuel a marathon (making 'hitting the wall' seem inevitable, or implied that maximal glycogen loading is required in order to complete a marathon without 'hitting the wall.' The present computational study demonstrates that the energetic constraints on endurance runners are more subtle, and depend on several physiologic variables including the muscle mass distribution, liver and muscle glycogen densities, and running speed (exercise intensity as a fraction of aerobic capacity of individual runners, in personalized but nevertheless quantifiable and predictable ways. The analytic approach presented here is used to estimate the distance at which runners will exhaust their glycogen stores as a function of running intensity. In so doing it also provides a basis for guidelines ensuring the safety and optimizing the performance of endurance runners, both by setting personally appropriate paces and by prescribing midrace fueling requirements for avoiding 'the wall.' The present analysis also sheds physiologically principled light on important standards in marathon running that until now have remained empirically defined: The qualifying times for the Boston Marathon.

  14. Fibroblast growth factor expression in the postnatal growth plate.

    Science.gov (United States)

    Lazarus, Jacob E; Hegde, Anita; Andrade, Anenisia C; Nilsson, Ola; Baron, Jeffrey

    2007-03-01

    Fibroblast growth factor (FGF) signaling is essential for endochondral bone formation. Mutations cause skeletal dysplasias including achondroplasia, the most common human skeletal dysplasia. Most previous work in this area has focused on embryonic chondrogenesis. To explore the role of FGF signaling in the postnatal growth plate, we quantitated expression of FGFs and FGF receptors (FGFRs) and examined both their spatial and temporal regulation. Toward this aim, rat proximal tibial growth plates and surrounding tissues were microdissected, and specific mRNAs were quantitated by real-time RT-PCR. To assess the FGF system without bias, we first screened for expression of all known FGFs and major FGFR isoforms. Perichondrium expressed FGFs 1, 2, 6, 7, 9, and 18 and, at lower levels, FGFs 21 and 22. Growth plate expressed FGFs 2, 7, 18, and 22. Perichondrial expression was generally greater than growth plate expression, supporting the concept that perichondrial FGFs regulate growth plate chondrogenesis. Nevertheless, FGFs synthesized by growth plate chondrocytes may be physiologically important because of their proximity to target receptors. In growth plate, we found expression of FGFRs 1, 2, and 3, primarily, but not exclusively, the c isoforms. FGFRs 1 and 3, thought to negatively regulate chondrogenesis, were expressed at greater levels and at later stages of chondrocyte differentiation, with FGFR1 upregulated in the hypertrophic zone and FGFR3 upregulated in both proliferative and hypertrophic zones. In contrast, FGFRs 2 and 4, putative positive regulators, were expressed at earlier stages of differentiation, with FGFR2 upregulated in the resting zone and FGFR4 in the resting and proliferative zones. FGFRL1, a presumed decoy receptor, was expressed in the resting zone. With increasing age and decreasing growth velocity, FGFR2 and 4 expression was downregulated in proliferative zone. Perichondrial FGF1, FGF7, FGF18, and FGF22 were upregulated. In summary, we have

  15. Discerning environmental factors affecting current tree growth in Central Europe.

    Science.gov (United States)

    Cienciala, Emil; Russ, Radek; Šantrůčková, Hana; Altman, Jan; Kopáček, Jiří; Hůnová, Iva; Štěpánek, Petr; Oulehle, Filip; Tumajer, Jan; Ståhl, Göran

    2016-12-15

    We examined the effect of individual environmental factors on the current spruce tree growth assessed from a repeated country-level statistical landscape (incl. forest) survey in the Czech Republic. An extensive set of variables related to tree size, competition, site characteristics including soil texture, chemistry, N deposition and climate was tested within a random-effect model to explain growth in the conditions of dominantly managed forest ecosystems. The current spruce basal area increment was assessed from two consecutive landscape surveys conducted in 2008/2009 and six years later in 2014/2015. Tree size, age and competition within forest stands were found to be the dominant explanatory variables, whereas the expression of site characteristics, environmental and climatic drives was weaker. The significant site variables affecting growth included soil C/N ratio and soil exchangeable acidity (pH KCl; positive response) reflecting soil chemistry, long-term N-deposition (averaged since 1975) in combination with soil texture (clay content) and Standardized Precipitation Index (SPI), a drought index expressing moisture conditions. Sensitivity of growth to N-deposition was positive, although weak. SPI was positively related to and significant in explaining tree growth when expressed for the growth season. Except SPI, no significant relation of growth was determined to altitude-related variables (temperature, growth season length). We identified the current spruce growth optimum at elevations about 800ma.s.l. or higher in the conditions of the country. This suggests that at lower elevations, limitation by a more pronounced water deficit dominates, whereas direct temperature limitation may concern the less frequent higher elevations. The mixed linear model of spruce tree growth explained 55 and 65% of the variability with fixed and random effects included, respectively, and provided new insights on the current spruce tree growth and factors affecting it within the

  16. Effect of hepatocyte growth factor and transforming growth factor-β1 on atrial fibroblasts fibrosis

    Institute of Scientific and Technical Information of China (English)

    张建成

    2012-01-01

    Objective To investigate the effect of hepatocyte growth factor (HGF) and transforming growth factor-β1 (TGFβ1) on the expression of α-smooth muscle actin(α-SMA) and collagen I in human atrial fibroblast in vitro, and to explore the possible molecular mechanism of atrial fibrosis in patients

  17. Natural selection of stellar civilizations by the limits of growth

    Science.gov (United States)

    Papagiannis, M. D.

    1983-10-01

    Evolution occurs in any system that possesses degrees of freedom to allow the appearance of new entities and constraints to select a few of them to become part of the system which in this manner continues to evolve. The limits of growth in a finite system, which will be imposed on all stellar civilizations by the colossal distances that separate the stars, will become the constraint that will affect the natural selection of these civilizations. Those that will manage to overcome their innate tendencies toward continuous material growth and replace them with non-material goals will be the only ones to survive this crisis. As a result the entire galaxy in a cosmically short period will become populated by stable, highly ethical and spiritual civilizations.

  18. The limits of precision monomer placement in chain growth polymerization

    Science.gov (United States)

    Gody, Guillaume; Zetterlund, Per B.; Perrier, Sébastien; Harrisson, Simon

    2016-02-01

    Precise control over the location of monomers in a polymer chain has been described as the `Holy Grail' of polymer synthesis. Controlled chain growth polymerization techniques have brought this goal closer, allowing the preparation of multiblock copolymers with ordered sequences of functional monomers. Such structures have promising applications ranging from medicine to materials engineering. Here we show, however, that the statistical nature of chain growth polymerization places strong limits on the control that can be obtained. We demonstrate that monomer locations are distributed according to surprisingly simple laws related to the Poisson or beta distributions. The degree of control is quantified in terms of the yield of the desired structure and the standard deviation of the appropriate distribution, allowing comparison between different synthetic techniques. This analysis establishes experimental requirements for the design of polymeric chains with controlled sequence of functionalities, which balance precise control of structure with simplicity of synthesis.

  19. Growth dependence of conjugation explains limited plasmid invasion in biofilms: an individual‐based modelling study

    DEFF Research Database (Denmark)

    Merkey, Brian; Lardon, Laurent; Seoane, Jose Miguel;

    2011-01-01

    . By extending an individual‐based model of microbial growth and interactions to include the dynamics of plasmid carriage and transfer by individual cells, we were able to conduct in silico tests of this and other hypotheses on the dynamics of conjugal plasmid transfer in biofilms. For a generic model plasmid...... and scan speed) and spatial reach (EPS yield, conjugal pilus length) are more important for successful plasmid invasion than the recipients' growth rate or the probability of segregational loss. While this study identifies one factor that can limit plasmid invasion in biofilms, the new individual......Plasmid invasion in biofilms is often surprisingly limited in spite of the close contact of cells in a biofilm. We hypothesized that this poor plasmid spread into deeper biofilm layers is caused by a dependence of conjugation on the growth rate (relative to the maximum growth rate) of the donor...

  20. The growth responses of coastal dune species are determined by nutrient limitation and sand burial.

    Science.gov (United States)

    Gilbert, Matthew; Pammenter, Norman; Ripley, Brad

    2008-05-01

    Past work suggests that burial and low nutrient availability limit the growth and zonal distribution of coastal dune plants. Given the importance of these two factors, there is a surprising lack of field investigations of the interactions between burial and nutrient availability. This study aims to address this issue by measuring the growth responses of four coastal dune plant species to these two factors and their interaction. Species that naturally experience either high or low rates of burial were selected and a factorial burial by nutrient addition experiment was conducted. Growth characteristics were measured in order to determine which characteristics allow a species to respond to burial. Species that naturally experience high rates of burial (Arctotheca populifolia and Scaevola plumieri) displayed increased growth when buried, and this response was nutrient-limited. Stable-dune species had either small (Myrica cordifolia, N-fixer) or negligible responses to burial (Metalasia muricata), and were not nutrient-limited. This interspecific difference in response to burial and/or fertiliser is consistent with the idea that burial maintains the observed zonation of species on coastal dunes. Species that are unable to respond to burial are prevented from occupying the mobile dunes. Species able to cope with high rates of burial had high nitrogen-use efficiencies and low dry mass costs of production, explaining their ability to respond to burial under nutrient limitation. The interaction between burial and nutrient limitation is understudied but vital to understanding the zonation of coastal dune plant species.

  1. Epidermal Growth Factor and Intestinal Barrier Function

    Directory of Open Access Journals (Sweden)

    Xiaopeng Tang

    2016-01-01

    Full Text Available Epidermal growth factor (EGF is a 53-amino acid peptide that plays an important role in regulating cell growth, survival, migration, apoptosis, proliferation, and differentiation. In addition, EGF has been established to be an effective intestinal regulator helping to protect intestinal barrier integrity, which was essential for the absorption of nutrients and health in humans and animals. Several researches have demonstrated that EGF via binding to the EGF receptor and subsequent activation of Ras/MAPK, PI3K/AKT, PLC-γ/PKC, and STATS signal pathways regulates intestinal barrier function. In this review, the relationship between epidermal growth factor and intestinal development and intestinal barrier is described, to provide a better understanding of the effects of EGF on intestine development and health.

  2. Growth factor interactions in bone regeneration

    NARCIS (Netherlands)

    Kempen, D.H.R.; Creemers, L.B.; Alblas, J.; Lu, L.; Verbout, A.J.; Yaszemski, M.J.; Dhert, W.J.A.

    2010-01-01

    Growth factor interactions in bone regeneration. Diederik H R Kempen, Laura B Creemers, Jacqueline Alblas, Lichun Lu, Abraham J Verbout, Michael J Yaszemski and Wouter J A Dhert 1 Department of Orthopedics, University Medical Center , Utrecht, The Netherlands . AbstractBuy the PDF Pubmed abstract

  3. Growth Factor Interactions in Bone Regeneration

    NARCIS (Netherlands)

    Kempen, Diederik H. R.; Creemers, Laura B.; Alblas, Jacqueline; Lu, Lichun; Verbout, Abraham J.; Yaszemski, Michael J.; Dhert, Wouter J. A.

    2010-01-01

    Bone regeneration is a complex process regulated by a large number of bioactive molecules. Many growth factors and cytokines involved in the natural process of bone healing have been identified and tested as potential therapeutic candidates to enhance the regeneration process. Although many of these

  4. Growth factor interactions in bone regeneration

    NARCIS (Netherlands)

    Kempen, D.H.R.; Creemers, L.B.; Alblas, J.; Lu, L.; Verbout, A.J.; Yaszemski, M.J.; Dhert, W.J.A.

    2010-01-01

    Growth factor interactions in bone regeneration. Diederik H R Kempen, Laura B Creemers, Jacqueline Alblas, Lichun Lu, Abraham J Verbout, Michael J Yaszemski and Wouter J A Dhert 1 Department of Orthopedics, University Medical Center , Utrecht, The Netherlands . AbstractBuy the PDF Pubmed abstract Ge

  5. Extracellular matrix-inspired growth factor delivery systems for bone regeneration

    Energy Technology Data Exchange (ETDEWEB)

    Martino, Mikaël M. [Osaka Univ. (Japan). Immunology Frontier Research Center; Briquez, Priscilla S. [Ecole Polytechnique Federale de Lausanne (Switzerland). Inst. of Bioengineering; Maruyama, Kenta [Osaka Univ. (Japan). Immunology Frontier Research Center; Hubbell, Jeffrey A. [Ecole Polytechnique Federale de Lausanne (Switzerland). Inst. of Bioengineering; Univ. of Chicago, IL (United States). Inst. for Molecular Engineering; Argonne National Lab. (ANL), Argonne, IL (United States)

    2015-04-17

    Growth factors are very promising molecules to enhance bone regeneration. However, their translation to clinical use has been seriously limited, facing issues related to safety and cost-effectiveness. These problems derive from the vastly supra-physiological doses of growth factor used without optimized delivery systems. Therefore, these issues have motivated the development of new delivery systems allowing better control of the spatio-temporal release and signaling of growth factors. Because the extracellular matrix (ECM) naturally plays a fundamental role in coordinating growth factor activity in vivo, a number of novel delivery systems have been inspired by the growth factor regulatory function of the ECM. After introducing the role of growth factors during the bone regeneration process, this review exposes different issues that growth factor-based therapies have encountered in the clinic and highlights recent delivery approaches based on the natural interaction between growth factor and the ECM.

  6. Transforming growth factor-β and Smads.

    Science.gov (United States)

    Lan, Hui Yao; Chung, Arthur C K

    2011-01-01

    Diabetic nephropathy (DN) is a major diabetic complication. Transforming growth factor-β(TGF-β) is a key mediator in the development of diabetic complications. It is well known that TGF-β exerts its biological effects by activating downstream mediators, called Smad2and Smad3, which is negatively regulated by an inhibitory Smad7. Recent studies also demonstrated that under disease conditions Smads act as signal integrators and interact with other signaling pathways such as the MAPK and NF-κB pathways. In addition, Smad2and Smad3 can reciprocally regulate target genes of TGF-β signaling. Novel research into microRNA has revealed the complexity of TGF-β signaling during DN. It has been found that TGF-β and elevated glucose concentration can positively regulate miR-192 and miR-377, but negatively regulate miR-29a in a diabetic milieu. These microRNAs are found to contribute to DN. Although targeting TGF-β may exert adverse effects on immune system, therapeutic approach against TGF-β signaling during DN still draws much attention. Blocking TGF-β signaling by neutralizing antibody, anti-sense oligonucleotides, and soluble receptors have been tested, but effects are limited. Gene transfer of Smad7 into diseased kidneys demonstrates a prominent inhibition on renal fibrosis and amelioration of renal impairment. Alteration of TGF-β-regulated microRNA expression in diseased kidneys may provide an alternative therapeutic approach against DN. In conclusion, TGF-β/Smad signaling plays a critical role in DN. A better understanding of the role of TGF-β/Smad signaling in the development of DN should provide an effective therapeutic strategy to combat DN.

  7. Fibroblast growth factor 23 and its receptors.

    Science.gov (United States)

    Yu, Xijie; White, Kenneth E

    2005-08-01

    Fibroblast growth factor 23 (FGF23) is a circulating factor that plays critical roles in phosphate and vitamin D metabolism, as evidenced by the fact that FGF23 missense mutations cause autosomal dominant hypophosphatemic rickets (ADHR). Autosomal dominant hypophosphatemic rickets is characterized by hypophosphatemia with inappropriately normal 1,25-dihydroxyvitamin D concentrations, as well as bone pain, fracture and rickets. This phenotype parallels that of patients with tumor induced osteomalacia (TIO), X-linked hypophosphatemic rickets (XLH), and fibrous dysplasia (FD), in whom elevated serum FGF23 levels are often observed. The fibroblast growth factor receptors (FGFR1-4) play key roles in skeletal development, as well as in normal metabolic processes. Several FGFR isoforms that potentially mediate the activity of FGF23 have been implicated. In the short term, these findings will lead to further understanding of FGF23 function, and potentially in the long term, to targeted therapies in disorders of hypo- and hyperphosphatemia that involve FGF23.

  8. Quantifying environmental limiting factors on tree cover using geospatial data.

    Directory of Open Access Journals (Sweden)

    Jonathan A Greenberg

    Full Text Available Environmental limiting factors (ELFs are the thresholds that determine the maximum or minimum biological response for a given suite of environmental conditions. We asked the following questions: 1 Can we detect ELFs on percent tree cover across the eastern slopes of the Lake Tahoe Basin, NV? 2 How are the ELFs distributed spatially? 3 To what extent are unmeasured environmental factors limiting tree cover? ELFs are difficult to quantify as they require significant sample sizes. We addressed this by using geospatial data over a relatively large spatial extent, where the wall-to-wall sampling ensures the inclusion of rare data points which define the minimum or maximum response to environmental factors. We tested mean temperature, minimum temperature, potential evapotranspiration (PET and PET minus precipitation (PET-P as potential limiting factors on percent tree cover. We found that the study area showed system-wide limitations on tree cover, and each of the factors showed evidence of being limiting on tree cover. However, only 1.2% of the total area appeared to be limited by the four (4 environmental factors, suggesting other unmeasured factors are limiting much of the tree cover in the study area. Where sites were near their theoretical maximum, non-forest sites (tree cover < 25% were primarily limited by cold mean temperatures, open-canopy forest sites (tree cover between 25% and 60% were primarily limited by evaporative demand, and closed-canopy forests were not limited by any particular environmental factor. The detection of ELFs is necessary in order to fully understand the width of limitations that species experience within their geographic range.

  9. Fibroblast growth factor 23 and dietary factors in renal disease

    NARCIS (Netherlands)

    da Cunha Baia, Leandro

    2015-01-01

    Omega-3 poly-unsaturated fatty acids and mineral metabolism: novel therapy for cardiovascular disease in renal patients? Deregulations in mineral metabolism, particularly related to phosphate and its regulating hormone fibroblast growth factor 23 (FGF23), are common in patients with chronic kidney d

  10. Growth Factors and Tension-Induced Skeletal Muscle Growth

    Science.gov (United States)

    Vandenburgh, Herman H.

    1994-01-01

    The project investigated biochemical mechanisms to enhance skeletal muscle growth, and developed a computer based mechanical cell stimulator system. The biochemicals investigated in this study were insulin/(Insulin like Growth Factor) IGF-1 and Steroids. In order to analyze which growth factors are essential for stretch-induced muscle growth in vitro, we developed a defined, serum-free medium in which the differentiated, cultured avian muscle fibers could be maintained for extended periods of time. The defined medium (muscle maintenance medium, MM medium) maintains the nitrogen balance of the myofibers for 3 to 7 days, based on myofiber diameter measurements and myosin heavy chain content. Insulin and IGF-1, but not IGF-2, induced pronounced myofiber hypertrophy when added to this medium. In 5 to 7 days, muscle fiber diameters increase by 71 % to 98% compared to untreated controls. Mechanical stimulation of the avian muscle fibers in MM medium increased the sensitivity of the cells to insulin and IGF-1, based on a leftward shift of the insulin dose/response curve for protein synthesis rates. (54). We developed a ligand binding assay for IGF-1 binding proteins and found that the avian skeletal muscle cultures produced three major species of 31, 36 and 43 kD molecular weight (54) Stretch of the myofibers was found to have no significant effect on the efflux of IGF-1 binding proteins, but addition of exogenous collagen stimulated IGF-1 binding protein production 1.5 to 5 fold. Steroid hormones have a profound effect on muscle protein turnover rates in vivo, with the stress-related glucocorticoids inducing rapid skeletal muscle atrophy while androgenic steroids induce skeletal muscle growth. Exercise in humans and animals reduces the catabolic effects of glucocorticoids and may enhance the anabolic effects of androgenic steroids on skeletal muscle. In our continuing work on the involvement of exogenrus growth factors in stretch-induced avian skeletal muscle growth, we

  11. Growth factor expression in degenerated intervertebral disc tissue. An immunohistochemical analysis of transforming growth factor beta, fibroblast growth factor and platelet-derived growth factor.

    Science.gov (United States)

    Tolonen, Jukka; Grönblad, Mats; Vanharanta, Heikki; Virri, Johanna; Guyer, Richard D; Rytömaa, Tapio; Karaharju, Erkki O

    2006-05-01

    Degenerated intervertebral disc has lost its normal architecture, and there are changes both in the nuclear and annular parts of the disc. Changes in cell shape, especially in the annulus fibrosus, have been reported. During degeneration the cells become more rounded, chondrocyte-like, whereas in the normal condition annular cells are more spindle shaped. These chondrocyte-like cells, often forming clusters, affect extracellular matrix turnover. In previous studies transforming growth factor beta (TGFbeta) -1 and -2, basic fibroblast growth factor (bFGF) and platelet-derived growth factor (PDGF) have been highlighted in herniated intervertebral disc tissue. In the present study the same growth factors are analysed immunohistochemically in degenerated intervertebral disc tissue. Disc material was obtained from 16 discs operated for painful degenerative disc disease. Discs were classified according to the Dallas Discogram Description. Different disc regions were analysed in parallel. As normal control disc tissue material from eight organ donors was used. Polyclonal antibodies against different growth factors and TGFbeta receptor type II were used, and the immunoreaction was detected by the avidin biotin complex method. All studied degenerated discs showed immunoreactivity for TGFbeta receptor type II and bFGF. Fifteen of 16 discs were immunopositive for TGFbeta-1 and -2, respectively, and none showed immunoreaction for PDGF. Immunopositivity was located in blood vessels and in disc cells. In the nucleus pulposus the immunoreaction was located almost exclusively in chondrocyte-like disc cells, whereas in the annular region this reaction was either in chondrocyte-like disc cells, often forming clusters, or in fibroblast-like disc cells. Chondrocyte-like disc cells were especially prevalent in the posterior disrupted area. In the anterior area of the annulus fibrosus the distribution was more even between these two cell types. bFGF was expressed in the anterior annulus

  12. Dual delivery of vascular endothelial growth factor and hepatocyte growth factor coacervate displays strong angiogenic effects.

    Science.gov (United States)

    Awada, Hassan K; Johnson, Noah R; Wang, Yadong

    2014-05-01

    Controlled delivery of multiple growth factors (GFs) holds great potential for the clinical treatment of ischemic diseases and might be more therapeutically effective to reestablish vasculature than the provision of a single GF. Vascular endothelial growth factor (VEGF) and hepatocyte growth factor (HGF) are two potent angiogenic factors. However, due to rapid degradation and dilution in the body, their clinical potential will rely on an effective mode of delivery. A coacervate, composed of heparin and a biodegradable polycation, which protects GFs from proteolysis and potentiates their bioactivities, is developed. Here, the coacervate incorporates VEGF and HGF and sustains their release for at least three weeks. Their strong angiogenic effects on endothelial cell proliferation and tube formation in vitro are confirmed. Furthermore, it is demonstrated that coacervate-based delivery of these factors has stronger effects than free application of both factors and to coacervate delivery of each GF separately.

  13. Epidermal Growth Factor Receptor in Pancreatic Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira-Cunha, Melissa, E-mail: melissacunha@doctors.org.uk [Hepatobiliary Surgery Unit, Manchester Royal Infirmary, Oxford Road, Manchester, M13 9WL (United Kingdom); Newman, William G. [Genetic Medicine, MAHSC, University of Manchester, St Mary' s Hospital, Oxford Road, Manchester, M13 9WL (United Kingdom); Siriwardena, Ajith K. [Hepatobiliary Surgery Unit, Manchester Royal Infirmary, Oxford Road, Manchester, M13 9WL (United Kingdom)

    2011-03-24

    Pancreatic cancer is the fourth leading cause of cancer related death. The difficulty in detecting pancreatic cancer at an early stage, aggressiveness and the lack of effective therapy all contribute to the high mortality. Epidermal growth factor receptor (EGFR) is a transmembrane glycoprotein, which is expressed in normal human tissues. It is a member of the tyrosine kinase family of growth factors receptors and is encoded by proto-oncogenes. Several studies have demonstrated that EGFR is over-expressed in pancreatic cancer. Over-expression correlates with more advanced disease, poor survival and the presence of metastases. Therefore, inhibition of the EGFR signaling pathway is an attractive therapeutic target. Although several combinations of EGFR inhibitors with chemotherapy demonstrate inhibition of tumor-induced angiogenesis, tumor cell apoptosis and regression in xenograft models, these benefits remain to be confirmed. Multimodality treatment incorporating EGFR-inhibition is emerging as a novel strategy in the treatment of pancreatic cancer.

  14. Fibroblast growth factor 23--et fosfatregulerende hormon

    DEFF Research Database (Denmark)

    Beck-Nielsen, Signe Sparre; Pedersen, Susanne Møller; Kassem, Moustapha

    2010-01-01

    Fibroblast growth factor 23 (FGF23) is a recently identified phosphatonin. Its main physiological functions are to maintain serum phosphate within its reference range and to counter regulate the effects of vitamin D. Diseases correlated to high serum values of FGF23 are hypophosphatemic rickets......, fibrous dysplasia, and tumour-induced osteomalacia. In contrast, hyperphosphatemic tumoral calcinosis is associated with accelerated degradation of FGF23. Measuring FGF23 serves as a differential diagnostic tool in elucidating conditions of long-lasting hypophosphatemia....

  15. Cellular signaling by fibroblast growth factor receptors.

    Science.gov (United States)

    Eswarakumar, V P; Lax, I; Schlessinger, J

    2005-04-01

    The 22 members of the fibroblast growth factor (FGF) family of growth factors mediate their cellular responses by binding to and activating the different isoforms encoded by the four receptor tyrosine kinases (RTKs) designated FGFR1, FGFR2, FGFR3 and FGFR4. Unlike other growth factors, FGFs act in concert with heparin or heparan sulfate proteoglycan (HSPG) to activate FGFRs and to induce the pleiotropic responses that lead to the variety of cellular responses induced by this large family of growth factors. A variety of human skeletal dysplasias have been linked to specific point mutations in FGFR1, FGFR2 and FGFR3 leading to severe impairment in cranial, digital and skeletal development. Gain of function mutations in FGFRs were also identified in a variety of human cancers such as myeloproliferative syndromes, lymphomas, prostate and breast cancers as well as other malignant diseases. The binding of FGF and HSPG to the extracellular ligand domain of FGFR induces receptor dimerization, activation and autophosphorylation of multiple tyrosine residues in the cytoplasmic domain of the receptor molecule. A variety of signaling proteins are phosphorylated in response to FGF stimulation including Shc, phospholipase-Cgamma, STAT1, Gab1 and FRS2alpha leading to stimulation of intracellular signaling pathways that control cell proliferation, cell differentiation, cell migration, cell survival and cell shape. The docking proteins FRS2alpha and FRS2beta are major mediators of the Ras/MAPK and PI-3 kinase/Akt signaling pathways as well as negative feedback mechanisms that fine-tune the signal that is initiated at the cell surface following FGFR stimulation.

  16. Fibroblast growth factor 19 entry into brain

    OpenAIRE

    Hsuchou, Hung; Pan, Weihong; Kastin, Abba J.

    2013-01-01

    Background Fibroblast growth factor (FGF)-19, an endocrine FGF protein mainly produced by the ileum, stimulates metabolic activity and alleviates obesity. FGF19 modulates metabolism after either intravenous or intracerebroventricular injection, and its receptor FGFR4 is present in the hypothalamus. This led to the question whether blood-borne FGF19 crosses the blood-brain barrier (BBB) to exert its metabolic effects. Methods We determined the pharmacokinetics of FGF19 permeation from blood to...

  17. Hepatocyte growth factor and vascular endothelial growth factor in ischaemic heart disease.

    Science.gov (United States)

    Suzuki, Hiroshi; Murakami, Mikitaka; Shoji, Makoto; Iso, Yoshitaka; Kondo, Takeshi; Shibata, Masayuki; Ezumi, Hitoshi; Hamazaki, Yuji; Koba, Shinji; Katagiri, Takashi

    2003-06-01

    Hepatocyte growth factor (HGF) and vascular endothelial growth factor (VEGF) are endothelial cell-specific growth factors, but the production of these growth factors in cardiomyocytes has also been demonstrated. However, there have been no reports focusing their attention on the changes in these growth factors after coronary intervention. We investigated the time-course changes of the serum VEGF and HGF levels in angina pectoris (AP) and acute myocardial infarction (AMI). The serum HGF and VEGF levels were measured in 60 patients with AP, in 62 patients with AMI (AP, before heparin administration, and at 24 and 48 hours, and one week after intervention; AMI, before heparin, and at 48 and 72 hours, and one, two, three and four weeks) and in 56 patients with neurocirculatory asthenia as controls. We defined the patients with remodelling who showed an increase in left ventricular end-diastolic volume index (LVEDVI) in the sub-acute phase of AMI. Hepatocyte growth factor levels in the AP and AMI were significantly higher than that in the control (p<0.0001). The AMI level was also significantly higher than AP (p<0.001). In the AMI and AP, HGF peaked at 48 hours. Vascular endothelial growth factor level in the AMI was significantly higher than that in the control and AP (p<0.0001). In the AMI, VEGF peaked at two weeks. There was a significant positive correlation between the peak VEGF and LVEDVI in the sub-acute phase of AMI (p=0.0089, r=0.436). Peak VEGF in the remodelling (+) group was significantly higher than that in the remodelling (-) group (p<0.001). In the AP, VEGF was unchanged. While both myocardial and vascular damage contribute to an increase in HGF level, vascular damage is not associated with the increase in VEGF. Vascular endothelial growth factor might be related to left ventricular remodelling in the sub-acute phase of myocardial infarction.

  18. Serum platelet-derived growth factor and fibroblast growth factor in patients with benign and malignant ovarian tumors

    DEFF Research Database (Denmark)

    Madsen, Christine Vestergaard; Steffensen, Karina Dahl; Olsen, Dorte Aalund

    2012-01-01

    New biological markers with predictive or prognostic value are highly warranted in the treatment of ovarian cancer. The platelet-derived growth factor (PDGF) system and fibroblast growth factor (FGF) system are important components in tumor growth and angiogenesis.......New biological markers with predictive or prognostic value are highly warranted in the treatment of ovarian cancer. The platelet-derived growth factor (PDGF) system and fibroblast growth factor (FGF) system are important components in tumor growth and angiogenesis....

  19. 13 Factors Limiting Women's Involvement in Development: Lesson ...

    African Journals Online (AJOL)

    Nekky Umera

    the persistent and increasing burdens of poverty, malnutrition, poor health ... This paper investigates factors limiting an active involvement of rural women in .... and children, but decisions on economic and political issues are solely undertaken ...

  20. Critical Success Factors for Limited Service Hotels in Malaysia

    OpenAIRE

    Wong, Chee Keng

    2015-01-01

    Critical success factors were used originally in Information technology areas when it was first introduced but has since been applied generically in other industries. This study explores the critical success factors for limited service hotels in Malaysia from both customer and hotel operator/ business owners’ perspective. The literature presents information from tourism in general and in Malaysia, definition of limited service hotels and its relevance to the hospitality industry in Malaysia, ...

  1. Gene duplication models for directed networks with limits on growth

    Science.gov (United States)

    Enemark, Jakob; Sneppen, Kim

    2007-11-01

    Background: Duplication of genes is important for evolution of molecular networks. Many authors have therefore considered gene duplication as a driving force in shaping the topology of molecular networks. In particular it has been noted that growth via duplication would act as an implicit means of preferential attachment, and thereby provide the observed broad degree distributions of molecular networks. Results: We extend current models of gene duplication and rewiring by including directions and the fact that molecular networks are not a result of unidirectional growth. We introduce upstream sites and downstream shapes to quantify potential links during duplication and rewiring. We find that this in itself generates the observed scaling of transcription factors for genome sites in prokaryotes. The dynamical model can generate a scale-free degree distribution, p(k)\\propto 1/k^{\\gamma } , with exponent γ = 1 in the non-growing case, and with γ>1 when the network is growing. Conclusions: We find that duplication of genes followed by substantial recombination of upstream regions could generate features of genetic regulatory networks. Our steady state degree distribution is however too broad to be consistent with data, thereby suggesting that selective pruning acts as a main additional constraint on duplicated genes. Our analysis shows that gene duplication can only be a main cause for the observed broad degree distributions if there are also substantial recombinations between upstream regions of genes.

  2. Role of myeloid growth factors in chemotherapy induced neutropenia

    Directory of Open Access Journals (Sweden)

    Ravinutala Srinath Bharadwaj

    2016-10-01

    Full Text Available Neutropenia is a major dose limiting toxicity of many chemo therapeutic regimens. Haemopoietic colony - stimulating factors (CSFs have been shown to reduce the duration and severity of chemotherapy induced neutropenia (CIN and risk of febrile neutropenia. Supportive care with myeloid growth factors improve chemotherapy delivery by minimizing chemotherapy dose reductions or treatment delays by enabling the delivery of full dose chemotherapy (dose dense in short time intervals. The goal of this article is to give comprehensive review of current literature regarding medical practice guidelines and risk assessment models for appropriate use of myeloid growth factors and management of febrile neutropenia. [Int J Basic Clin Pharmacol 2016; 5(5.000: 1715-1721

  3. LIMITING FACTORS FOR THE DEVELOPMENT OF THE SERBIAN HOSPITALITY INDUSTRY

    OpenAIRE

    Nikolina Kosar; Sasa Masic; Lidija Barjaktarovic; Mihaela Lazovic

    2016-01-01

    Heterogeneity and complexity determine multidisciplinary approach to the hospitality research. Identification and analysis of limited hospitality development factors imply very complex scientific approach. Case study methodology is applied on Republic of Serbia, which is transition country and candidate for EU accession. Research results identified key factors which had impact on lag, stagnation and contemporary level of hospitality development. Firstly, way of executed privatizat...

  4. Carbon utilization by fruit limits shoot growth in alternate-bearing citrus trees.

    Science.gov (United States)

    Martínez-Alcántara, Belén; Iglesias, Domingo J; Reig, Carmina; Mesejo, Carlos; Agustí, Manuel; Primo-Millo, Eduardo

    2015-03-15

    Fruit load in alternate-bearing citrus trees is reported to alter shoot number and growth during spring, summer, and autumn flushes, and the source-sink balance, which affects the storage and mobilization of reserve nutrients. The aim of this work was to assess the extent of shoot growth inhibition resulting from the presence of fruits in 'Moncada' mandarin trees loaded with fruit (ON) or with very light fruit load (OFF), and to identify the role of carbohydrates and nitrogenous compounds in the competition between fruits and shoots. Growth of reproductive and vegetative organs was measured on a monthly basis. (13)C- and (15)N-labeled compounds were supplied to trace the allocation of reserve nutrients and subsequent translocation from source to sink. At the end of the year, OFF trees produced more abundant flushes (2.4- and 4.9-fold higher in number and biomass, respectively) than ON trees. Fruits from ON trees accumulated higher C amounts at the expense of developing flushes, whereas OFF trees exhibited the opposite pattern. An inverse relationship was identified between the amount of C utilized by fruits and vegetative flush growth. (13)C-labeling revealed an important role for mature leaves of fruit-bearing branches in supporting shoot/fruit growth, and the elevated sink strength of growing fruits on shoots. N availability for vegetative shoots was not affected by the presence or absence of fruits, which accumulated important amounts of (15)N. In conclusion, our results show that shoot growth is resource-limited as a consequence of fruit development, and vegetative-growth inhibition is caused by photoassimilate limitation. The competence for N is not a decisive factor in limiting vegetative growth under the experimental conditions of this study.

  5. An ideal preparation for dermal regeneration: skin renewal growth factors, the growth factor composites from porcine platelets.

    Science.gov (United States)

    Wang, Kuo-Hsien; Wu, Yo-Ping Greg; Lo, Wen-Cheng

    2012-12-01

    The use of growth factor composites from platelets has been introduced to many areas of clinical applications and studies. With the richest source of growth factors (GFs), beneficial effects have been shown on tissue regeneration and wound healing. However, animal and clinical studies have revealed inconsistent outcomes with the use of platelet-derived growth factors (PDGFs), which were likely due to variations in the presence and concentrations of GFs between various sources. Autologous PDGFs are considered to be safer, but they are limited by the feasibility of large-scale production to be used extensively in the acute phase, greater surface area, or general cosmetic applications. This study employed a simple process to obtain growth factor composites from activated platelets of porcine origin, namely skin renewal growth factors (SRGF). The functions of SRGF were subsequently evaluated on cultured human fibroblasts, keratinocytes, and melanocytes. Our data revealed that SRGF significantly promoted the proliferation of fibroblasts, accompanied by increased expression of collagens (types I, III, IV, and VIII) and proteoglycans. Diminished proliferation and arrested differentiation of keratinocytes were evidenced by the attenuated expression of laminin V and keratin 10. In addition, SRGF also suppressed the growth of melanocytes and reduced the expression of microphthalmia-associated transcription factor (MITF), tyrosinase, and paired box 3 (PAX3), which mediates melanogensis. Our results suggest that SRGF possesses beneficial properties and is a promising and cost-effective composition for the development of a safe cosmetic agent or topical products for skin regeneration. The development of SRGF may also provide an alternative strategy for tissue engineering.

  6. Thermal limits for growth and reproduction in the desert pupfish, Cyprinodon n. nevadensis

    Energy Technology Data Exchange (ETDEWEB)

    Gerking, S.D.; Lee, R.M.

    1979-01-01

    The thermal limits for growth of the desert pupfish (Cyprinodon n. nevadensis) were determined in seven-week laboratory feeding experiments at three rations (1.5, 3.0 and 4.5% body weight day) of Tetra-min prepared food and seven temperatures (12, 16, 20, 24, 28, 32, and 36 C). Curves of specific growth rates (% dry weight gain/day) as related to temperature were skewed to the left at the three rations. Growth was inhibited at 12, 16 and 36 C. Fish at the lower two temperatures were torpid and lacked appetite; the higher temperature fish did not eat sufficient food to match the high metabolic cost. The thermal scope for growth was narrowed as ration decreased and as age/size increased. Taking these factors into account, the thermal limits for growth of immature pupfish feeding at moderate to high rates were 17.5 to 31.0 C with optimum growth achieved at 22.0 C. Successful reproduction depends on egg production and egg viability.

  7. Dynamics of competitive systems with a single common limiting factor.

    Science.gov (United States)

    Kon, Ryusuke

    2015-02-01

    The concept of limiting factors (or regulating factors) succeeded in formulating the well-known principle of competitive exclusion. This paper shows that the concept of limiting factors is helpful not only to formulate the competitive exclusion principle, but also to obtain other ecological insights. To this end, by focusing on a specific community structure, we study the dynamics of Kolmogorov equations and show that it is possible to derive an ecologically insightful result only from the information about interactions between species and limiting factors. Furthermore, we find that the derived result is a generalization of the preceding work by Shigesada, Kawasaki, and Teramoto (1984), who examined a certain Lotka-Volterra equation in a different context.

  8. EXPRESSION OF GROWTH-FACTORS AND GROWTH-FACTOR RECEPTORS IN NORMAL AND TUMOROUS HUMAN THYROID TISSUES

    NARCIS (Netherlands)

    van der Laan, B.F.A.M.; FREEMAN, JL; ASA, SL

    1995-01-01

    A number of growth factors have been implicated as stimuli of thyroid cell proliferation; overexpression of these growth factors and/or their receptors may play a role in the growth of thyroid tumors. To determine if immunohistochemical detection of growth factors and/or their receptors correlates w

  9. The multiple interactions between growth factors and microenvironment in vivo

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Cell, growth factors and extracellular matrices (ECMs) coexist in a dynamic tissue envi- ronment. A knowledge of multiple interactions among them is highly important for effectively raising the biological activities of growth factors, regulating cell life cycle, designing and preparing exogenous mat- rices to control growth factors release in tissue or organ regeneration by engineering means. This paper addresses the characteristics and functions of growth factors, interactions between growth factors and ECMs, the manners and correlative signaling of growth factors acting on cells, and briefly summarizes the biomimetic requisites for controlled release mat- rices, hoping to provide a useful reference for co- rrelative research in tissue engineering.

  10. Parental factors associated with intrauterine growth restriction

    Directory of Open Access Journals (Sweden)

    Hăşmăşanu Monica G.

    2015-01-01

    Full Text Available Introduction. Linear growth failure is caused by multiple factors including parental factors. Objective. The aim of this study was to evaluate parental risk factors for intrauterine growth restriction (IUGR on a population of Romanian newborn infants in a tertiary level maternity facility for a period of 2.5 years. Methods. A retrospective matched case-control study was conducted in the Emergency County Hospital of Cluj-Napoca, a university hospital in North-Western Romania. The sample was selected from 4,790 infants admitted to the Neonatal Ward at 1st Gynecology Clinic between January 2012 and June 2014. Results. The age of mothers was significantly lower in the IUGR group compared to controls (p=0.041. A significantly higher percentage of mothers had hypertension in the IUGR group compared to those in the control group (p0.13. The age of fathers of infants with IUGR proved significantly lower compared to controls (p=0.0278. The analysis of infants’ comorbidities revealed no significant difference between groups for respiratory distress, hyperbilirubinemia, hypocalcaemia, and heart failure (p>0.27. Intracranial hemorrhage, necrotizing enterocolitis and hypoglycemia were significantly higher in the IUGR group compared to controls. The logistic regression identified hypertension as a significant risk factor for IUGR (OR=2.4, 95% CI [1.3-4.5]. Conclusion. Although the age of the mothers and fathers proved significantly lower in the IUGR group compared to controls, only hypertension in the mothers proved significant risk factors for IUGR.

  11. Factores de crecimiento III: factores transformadores del crecimiento (TGF Growth factors III part: transforming growth factors (TGF

    Directory of Open Access Journals (Sweden)

    Hilda Norha Jaramillo Londoño

    1996-04-01

    Full Text Available Se presenta una revisión de los conceptos básicos sobre los factores transformadores del crecimiento, tanto alfa como beta, incluyendo los siguientes aspectos: consideraciones generales, estructura bioquímica, concentraciones, proteínas transportadoras, receptores, mecanismos de acción y efectos biológicos. A review is presented on the basic concepts of Transforming Growth Factors both a and p; it includes general considerations, biochemical structure, concentrations, binding proteins, receptors, mechanisms of action, and biological effects.

  12. Growth phase- and nutrient limitation-associated transcript abundance regulation in Bordetella pertussis.

    Science.gov (United States)

    Nakamura, Mari M; Liew, Sin-Yee; Cummings, Craig A; Brinig, Mary M; Dieterich, Christine; Relman, David A

    2006-10-01

    To survive in a host environment, microbial pathogens must sense local conditions, including nutrient availability, and adjust their growth state and virulence functions accordingly. No comprehensive investigation of growth phase-related gene regulation in Bordetella pertussis has been reported previously. We characterized changes in genome-wide transcript abundance of B. pertussis as a function of growth phase and availability of glutamate, a key nutrient for this organism. Using a Bordetella DNA microarray, we discovered significant changes in transcript abundance for 861 array elements during the transition from log phase to stationary phase, including declining transcript levels of many virulence factor genes. The responses to glutamate depletion exhibited similarities to the responses induced by exit from log phase, including decreased virulence factor transcript levels. However, only 23% of array elements that showed at least a fourfold growth phase-associated difference in transcript abundance also exhibited glutamate depletion-associated changes, suggesting that nutrient limitation may be one of several interacting factors affecting gene regulation during stationary phase. Transcript abundance patterns of a Bvg+ phase-locked mutant revealed that the BvgAS two-component regulatory system is a key determinant of growth phase- and nutrient limitation-related transcriptional control. Several adhesin genes exhibited lower transcript abundance during stationary phase and under glutamate restriction conditions. The predicted bacterial phenotype was confirmed: adherence to bronchoepithelial cells decreased 3.3- and 4.4-fold at stationary phase and with glutamate deprivation, respectively. Growth phase and nutrient availability may serve as cues by which B. pertussis regulates virulence according to the stage of infection or the location within the human airway.

  13. Insulin-like growth factor and fibroblast growth factor expression profiles in growth-restricted fetal sheep pancreas.

    Science.gov (United States)

    Chen, Xiaochuan; Rozance, Paul J; Hay, William W; Limesand, Sean W

    2012-05-01

    Placental insufficiency results in intrauterine growth restriction (IUGR), impaired fetal insulin secretion and less fetal pancreatic β-cell mass, partly due to lower β-cell proliferation rates. Insulin-like growth factors (IGFs) and fibroblast growth factors (FGFs) regulate fetal β-cell proliferation and pancreas development, along with transcription factors, such as pancreatic and duodenal homeobox 1 (PDX-1). We determined expression levels for these growth factors, their receptors and IGF binding proteins in ovine fetal pancreas and isolated islets. In the IUGR pancreas, relative mRNA expression levels of IGF-I, PDX-1, FGF7 and FGFR2IIIb were 64% (P pancreas compared with controls. In isolated islets from IUGR fetuses, IGF-II and IGFBP-2 mRNA concentrations were 1.5- and 3.7-fold greater (P < 0.05), and insulin mRNA was 56% less (P < 0.05) than control islets. The growth factor expression profiles for IGF and FGF signaling pathways indicate that declines in β-cell mass are due to decreased growth factor signals for both pancreatic progenitor epithelial cell and mature β-cell replication.

  14. Fibroblast growth factor 23 - et fosfatregulerende hormon

    DEFF Research Database (Denmark)

    Beck-Nielsen, Signe; Pedersen, Susanne Møller; Kassem, Moustapha

    2010-01-01

    Fibroblast growth factor 23 (FGF23) er et nyligt identificeret fosfatonin. FGF23's fysiologiske hovedfunktion er at opretholde normalt serumfosfat og at virke som et D-vitaminmodregulatorisk hormon. Sygdomme, der er koblet til forhøjet serum FGF23, er hypofosfatæmisk rakitis, fibrøs dysplasi og...... tumorinduceret osteomalaci. Hyperfosfatæmisk familiær tumoral calcinosis er derimod associeret med forhøjet nedbrydning af FGF23. Måling af FGF23 er et differentialdiagnostisk redskab ved udredning af tilstande med længerevarende hypofosfatæmi. Udgivelsesdato: 2010-May 17...

  15. Increased toxicity of Karenia brevis during phosphate limited growth: ecological and evolutionary implications.

    Directory of Open Access Journals (Sweden)

    Donnie Ransom Hardison

    Full Text Available Karenia brevis is the dominant toxic red tide algal species in the Gulf of Mexico. It produces potent neurotoxins (brevetoxins [PbTxs], which negatively impact human and animal health, local economies, and ecosystem function. Field measurements have shown that cellular brevetoxin contents vary from 1-68 pg/cell but the source of this variability is uncertain. Increases in cellular toxicity caused by nutrient-limitation and inter-strain differences have been observed in many algal species. This study examined the effect of P-limitation of growth rate on cellular toxin concentrations in five Karenia brevis strains from different geographic locations. Phosphorous was selected because of evidence for regional P-limitation of algal growth in the Gulf of Mexico. Depending on the isolate, P-limited cells had 2.3- to 7.3-fold higher PbTx per cell than P-replete cells. The percent of cellular carbon associated with brevetoxins (%C-PbTx was ~ 0.7 to 2.1% in P-replete cells, but increased to 1.6-5% under P-limitation. Because PbTxs are potent anti-grazing compounds, this increased investment in PbTxs should enhance cellular survival during periods of nutrient-limited growth. The %C-PbTx was inversely related to the specific growth rate in both the nutrient-replete and P-limited cultures of all strains. This inverse relationship is consistent with an evolutionary tradeoff between carbon investment in PbTxs and other grazing defenses, and C investment in growth and reproduction. In aquatic environments where nutrient supply and grazing pressure often vary on different temporal and spatial scales, this tradeoff would be selectively advantageous as it would result in increased net population growth rates. The variation in PbTx/cell values observed in this study can account for the range of values observed in the field, including the highest values, which are not observed under N-limitation. These results suggest P-limitation is an important factor regulating

  16. Collagenous matrices as release carriers of exogenous growth factors.

    Science.gov (United States)

    Kanematsu, Akihiro; Yamamoto, Shingo; Ozeki, Makoto; Noguchi, Tetsuya; Kanatani, Isao; Ogawa, Osamu; Tabata, Yasuhiko

    2004-08-01

    We have investigated the use of natural and synthetic collagenous matrices as carriers of exogenous growth factors. A bladder acellular matrix (BAM) was processed from rat bladder and compared with sponge matrix of porcine type 1 collagen. The lyophilized matrices were rehydrated by the aqueous solutions of basic fibroblast growth factor (bFGF), hepatocyte growth factor (HGF), platelet derived growth factor-BB (PDGF-BB), vascular endothelial growth factor (VEGF), insulin like growth factor-1 (IGF-1) and heparin binding epidermal growth factor-like growth factor (HB-EGF), to obtain the matrix incorporating each growth factor. The rehydration method enabled the growth factor protein to distribute into the matrix homogeneously. In vivo release test in the mouse subcutis revealed that, the property of BAM for growth factor release was similar to that of collagen sponge. Among the growth factors examined, bFGF release was the most sustained, followed by HGF and PDGF-BB. bFGF released from the two matrices showed similar in vivo angiogenic activity at the mouse subcutis in a dose-dependent manner. These findings demonstrate that the collagenous matrices function as release carriers of growth factors. This feature is promising to create a scaffold, which has a nature to control the tissue regeneration actively.

  17. Nutrition and the insulin-like growth factor system.

    Science.gov (United States)

    Estívariz, C F; Ziegler, T R

    1997-08-01

    Nutritional status is a key regulator of the circulating and tissue insulin-like growth factor (IGF) system. IGF-I mRNA and protein levels decrease in tissues such as liver and intestine with fasting and are restored with refeeding. Additional studies suggest that the level of protein and calorie intake independently regulate plasma IGF-I concentrations in man. The level of nutrition effects the biological actions of recombinant growth hormone (GH) and IGF-I administration in humans. Limited data demonstrate that plasma and tissue levels of the insulin-like growth factor binding proteins (IGFBPs) are also sensitive to nutrient intake. Specific micronutrients, such as potassium, magnesium and zinc also appear to be important for optimal IGF-I synthesis and anabolic effects in animal models. Malnutrition is common in elderly patients, however, the interaction between specific nutrients, general nutritional status and the aging process on the IGF system is incompletely understood. Mechanisms of nutrient-IGF system interactions which may affect the biological actions of IGF-I, IGF-II, and the IGFBPs are increasingly being determined in basic studies. The effects of underlying nutritional status and responses to dietary intake will be important to evaluate in clinical studies of the IGF system and exogenous growth factor therapy.

  18. SERUM TRANSFORMING GROWTH FACTOR B1 AND PROSTATE

    African Journals Online (AJOL)

    tein expression associated with fibrotic condi- ... TGF—B1 AND PSA AS MARKERS OF PROSTATE CANCER ..... transforming growth factor-beta is significantly the cell surface in tumor progression ... growth factor for clear cell renal carcinoma.

  19. Familial growth hormone releasing factor deficiency in pseudopseudohypoparathyroidism.

    OpenAIRE

    Stirling, H F; Barr, D G; Kelnar, C J

    1991-01-01

    A mother with pseudopseudohypoparathyroidism and her short son showed poor spontaneous growth hormone secretion, and provocation tests suggested a deficiency of growth hormone releasing factor. This is the first report of growth hormone releasing factor deficiency in pseudopseudohypoparathyroidism. The boy has responded well to growth hormone treatment over a period of three years.

  20. Growth factors adsorbed on polyglycolic acid mesh augment growth of bioengineered intestinal neomucosa.

    Science.gov (United States)

    Wulkersdorfer, Beatrix; Kao, Kenneth K; Agopian, Vatche G; Dunn, James C; Wu, Ben M; Stelzner, Matthias

    2011-08-01

    Production of tissue engineered small intestine (TESI) has been limited by the relatively large amount of native tissue required to generate neomucosa. The influence of growth factors and three-dimensional (3D) extracellular matrices on TESI has been studied both in vitro and in vivo, and positive growth effects on tissue mass and differentiation were noted. The present study investigates the impact of single doses of glucagon-like peptide-2 (GLP-2), hepatocyte growth factor (HGF), or holo-transferrin adsorbed onto a polyglycolic (PGA) mesh scaffold using a rat small-intestinal organoid transplant model. In Experiment I, intestinal organoids were seeded onto PGA mesh discs, suspended in either Matrigel (n=8) or a vehicle control (n=8), and implanted into syngenic recipients. In Experiment II, GLP-2 (n=8), HGF (n=8), or transferrin (n=8) were adsorbed onto PGA mesh discs. Intestinal organoids were then suspended in Matrigel and seeded onto each growth factor-loaded PGA disc or onto control discs without growth factors (n=12). In addition, organoids were suspended in vehicle and seeded onto control discs (n=12). All discs were implanted into syngenic recipients. After 4 wk, histologic analysis of the samples revealed significantly greater neomucosal surface area (3.62±0.33 mm(2)versus 0.92±0.11 mm(2), Pvehicle controls. The addition of holo-transferrin to the scaffolds further augmented neomucosal surface area (9.11±0.66 mm(2)versus 3.01±0.22 mm(2), P<0.01), whereas that of GLP-2 stimulated the formation of increased numbers of cysts (8.88±0.46 versus 4.18±0.25, P<0.01). These data suggest that Matrigel and growth factors adsorbed to polymer scaffolds can be used to manipulate the morphology of TESI.

  1. The limited screening value of insulin-like growth factor-i as a marker for alterations in body composition in very long-term adult survivors of childhood cancer

    NARCIS (Netherlands)

    K. Blijdorp (Karin); M.M. van den Heuvel-Eibrink (Marry); R. Pieters (Rob); A.M. Boot (Annemieke); J.P. Sluimer (Johanna); A. van der Lelij (Allegonda); S.J.C.M.M. Neggers (Bas)

    2012-01-01

    textabstractBackground: The clinical relevance of low IGF-I levels, caused by cranial radiotherapy, in adult childhood cancer survivors has not been studied extensively. We evaluated whether IGF-I is a useful marker for altered body composition and growth hormone deficiency (GHD) in this group. Proc

  2. The limited screening value of insulin-like growth factor-i as a marker for alterations in body composition in very long-term adult survivors of childhood cancer

    NARCIS (Netherlands)

    Blijdorp, Karin; van den Heuvel-Eibrink, Marry; Pieters, Rob; Boot, Annemieke; Sluimer, Johanna; van der Lelij, Aart-Jan; Neggers, Sebastian

    2012-01-01

    Background The clinical relevance of low IGF-I levels, caused by cranial radiotherapy, in adult childhood cancer survivors has not been studied extensively. We evaluated whether IGF-I is a useful marker for altered body composition and growth hormone deficiency (GHD) in this group. Procedure We

  3. Early diet, insulin-like growth factor-1, growth and later obesity

    DEFF Research Database (Denmark)

    Michaelsen, Kim F; Larnkjær, Anni; Mølgaard, Christian

    2013-01-01

    . However, some studies suggest that weight gain during the 6- to 12-month age period, when complementary feeding is introduced, is not associated with later obesity. Insulin-like growth factor-1 (IGF-1) values and body composition both play a role in the complex pattern between early diet and later obesity......, but our present knowledge about how these factors are influenced by diet during infancy is limited. Future studies should include longitudinal data on IGF-1 and body composition during infancy to improve our understanding of how diet in early life can play a role in prevention of later obesity.......There is increasing evidence that factors in early life are important for the risk of developing overweight and obesity later in childhood. Among the postnatal factors, breastfeeding and complementary feeding are especially interesting because the pattern of these two factors can be changed...

  4. Activated human neutrophils release hepatocyte growth factor/scatter factor.

    LENUS (Irish Health Repository)

    McCourt, M

    2012-02-03

    BACKGROUND: Hepatocyte growth factor or scatter factor (HGF\\/SF) is a pleiotropic cytokine that has potent angiogenic properties. We have previously demonstrated that neutrophils (PMN) are directly angiogenic by releasing vascular endothelial growth factor (VEGF). We hypothesized that the acute inflammatory response can stimulate PMN to release HGF. AIMS: To examine the effects of inflammatory mediators on PMN HGF release and the effect of recombinant human HGF (rhHGF) on PMN adhesion receptor expression and PMN VEGF release. METHODS: In the first experiment, PMN were isolated from healthy volunteers and stimulated with tumour necrosis factor-alpha (TNF-alpha), lipopolysaccharide (LPS), interleukin-8 (IL-8), and formyl methionyl-leucyl-phenylalanine (fMLP). Culture supernatants were assayed for HGF using ELISA. In the second experiment, PMN were lysed to measure total HGF release and HGF expression in the PMN was detected by Western immunoblotting. Finally, PMN were stimulated with rhHGF. PMN CD 11a, CD 11b, and CD 18 receptor expression and VEGF release was measured using flow cytometry and ELISA respectively. RESULTS: TNF-alpha, LPS and fMLP stimulation resulted in significantly increased release of PMN HGF (755+\\/-216, 484+\\/-221 and 565+\\/-278 pg\\/ml, respectively) compared to controls (118+\\/-42 pg\\/ml). IL-8 had no effect. Total HGF release following cell lysis and Western blot suggests that HGF is released from intracellular stores. Recombinant human HGF did not alter PMN adhesion receptor expression and had no effect on PMN VEGF release. CONCLUSIONS: This study demonstrates that pro-inflammatory mediators can stimulate HGF release from a PMN intracellular store and that activated PMN in addition to secreting VEGF have further angiogenic potential by releasing HGF.

  5. Priming Dental Pulp Stem Cells With Fibroblast Growth Factor-2 Increases Angiogenesis of Implanted Tissue-Engineered Constructs Through Hepatocyte Growth Factor and Vascular Endothelial Growth Factor Secretion.

    Science.gov (United States)

    Gorin, Caroline; Rochefort, Gael Y; Bascetin, Rumeyza; Ying, Hanru; Lesieur, Julie; Sadoine, Jérémy; Beckouche, Nathan; Berndt, Sarah; Novais, Anita; Lesage, Matthieu; Hosten, Benoit; Vercellino, Laetitia; Merlet, Pascal; Le-Denmat, Dominique; Marchiol, Carmen; Letourneur, Didier; Nicoletti, Antonino; Vital, Sibylle Opsahl; Poliard, Anne; Salmon, Benjamin; Muller, Laurent; Chaussain, Catherine; Germain, Stéphane

    2016-03-01

    Tissue engineering strategies based on implanting cellularized biomaterials are promising therapeutic approaches for the reconstruction of large tissue defects. A major hurdle for the reliable establishment of such therapeutic approaches is the lack of rapid blood perfusion of the tissue construct to provide oxygen and nutrients. Numerous sources of mesenchymal stem cells (MSCs) displaying angiogenic potential have been characterized in the past years, including the adult dental pulp. Establishment of efficient strategies for improving angiogenesis in tissue constructs is nevertheless still an important challenge. Hypoxia was proposed as a priming treatment owing to its capacity to enhance the angiogenic potential of stem cells through vascular endothelial growth factor (VEGF) release. The present study aimed to characterize additional key factors regulating the angiogenic capacity of such MSCs, namely, dental pulp stem cells derived from deciduous teeth (SHED). We identified fibroblast growth factor-2 (FGF-2) as a potent inducer of the release of VEGF and hepatocyte growth factor (HGF) by SHED. We found that FGF-2 limited hypoxia-induced downregulation of HGF release. Using three-dimensional culture models of angiogenesis, we demonstrated that VEGF and HGF were both responsible for the high angiogenic potential of SHED through direct targeting of endothelial cells. In addition, FGF-2 treatment increased the fraction of Stro-1+/CD146+ progenitor cells. We then applied in vitro FGF-2 priming to SHED before encapsulation in hydrogels and in vivo subcutaneous implantation. Our results showed that FGF-2 priming is more efficient than hypoxia at increasing SHED-induced vascularization compared with nonprimed controls. Altogether, these data demonstrate that FGF-2 priming enhances the angiogenic potential of SHED through the secretion of both HGF and VEGF.

  6. The sustainability and transition of economic growth in China: from a perspective of factor structure

    Institute of Scientific and Technical Information of China (English)

    Wang Yafei; Wu Xiaohang

    2008-01-01

    After more than 20 years' high speed growth, the sustainable growth of Chinese economy faces serious lim-itation of resources and factors now and in the future. In order to maintain the economic growth, China has to trans, form the way of economic growth. Based on the analysis on the related theories of economic growth and the structur-al transformation in factors of production, this paper proposes that the transformation of the economic growth way has to impel the optimization and the promotion of the utilization structure of factors of production. Finally, based on the analysis of the necessity to change the pattern of economic growth, this paper proposes the strategic measures to promote the continuous economic growth and the transformation of patterns of economic growth.

  7. Quantifying Environmental Limiting Factors on Tree Cover Using Geospatial Data

    NARCIS (Netherlands)

    Greenberg, Jonathan; Ferreira Dos Santos, Maria Joao; Dobrowski, Solomon; Vanderbilt, Vern; Ustin, Susan

    2015-01-01

    Environmental limiting factors (ELFs) are the thresholds that determine the maximum or minimum biological response for a given suite of environmental conditions. We asked the following questions: 1) Can we detect ELFs on percent tree cover across the eastern slopes of the Lake Tahoe Basin, NV? 2) Ho

  8. [Growth Hormone-Insulin Growth Factor I (GH-IGF-I) axis and growth].

    Science.gov (United States)

    Castell, A-L; Sadoul, J-L; Bouvattier, C

    2013-10-01

    Normal human linear growth results from an evolutionary process expressing the sum effect of multiple genes. The growth hormone (GH) - insulin like growth factor (IGF)-I axis is one of the main actors in the growth process. Defects in this axis can be responsible for short or tall stature. Short stature is defined as smaller than - 2 standard deviations (SD). It is a very common reason for consultation in pediatrics; indeed, 2.5 % of children are concerned. Multiple causes make diagnosis difficult. In this article, we detail the most common constitutional causes of small size, including those related to a defect in the GH-IGF-I axis. Then, we report, the first results of the clinical and genetic study conducted on 213 patients with gigantism. Tall stature is defined by a height superior to 2 SD. Finally, recent work linking epigenetics and growth - via signaling pathways of GH-IGF-I axis - will be presented.

  9. Nerve growth factor interactions with mast cells.

    Science.gov (United States)

    Kritas, S K; Caraffa, A; Antinolfi, P; Saggini, A; Pantalone, A; Rosati, M; Tei, M; Speziali, A; Saggini, R; Pandolfi, F; Cerulli, G; Conti, P

    2014-01-01

    Neuropeptides are involved in neurogenic inflammation where there is vasodilation and plasma protein extravasion in response to this stimulus. Nerve growth factor (NGF), identified by Rita Levi Montalcini, is a neurotrophin family compound which is important for survival of nociceptive neurons during their development. Therefore, NGF is an important neuropeptide which mediates the development and functions of the central and peripheral nervous system. It also exerts its proinflammatory action, not only on mast cells but also in B and T cells, neutrophils and eosinophils. Human mast cells can be activated by neuropeptides to release potent mediators of inflammation, and they are found throughout the body, especially near blood vessels, epithelial tissue and nerves. Mast cells generate and release NGF after degranulation and they are involved in iperalgesia, neuroimmune interactions and tissue inflammation. NGF is also a potent degranulation factor for mast cells in vitro and in vivo, promoting differentiation and maturation of these cells and their precursor, acting as a co-factor with interleukin-3. In conclusion, these studies are focused on cross-talk between neuropeptide NGF and inflammatory mast cells.

  10. Epidermal growth factor in the rat lung

    DEFF Research Database (Denmark)

    Raaberg, Lasse; Poulsen, Steen Seier; Nexø, Ebba

    1991-01-01

    Epidermal Growth Factor (EGF) in pharmacological doses is able to induce precoccious lung maturation in rabbits and sheeps. As EGF is probably acting in a para- or autocrine way, we have searched for EGF in the lungs. We report EGF immunoreactivity to be present in the type II pneumocytes...... of the rat from a couple of days prior to birth and throughout life. Further, we report EGF immunoreactivity to be present in cells in the bronchi and the bronchioles from day 20-21 of gestation and throughout life. G-200 gelchromatography of lung extracts indicates that the EGF-reactive material is a high...... molecular weight form of EGF. Since previous studies have shown that EGF in pharmacological doses is able to promote lung maturation, our results may imply a physiological role for EGF in the lungs....

  11. Plasma rich in growth factors in dentistry

    Directory of Open Access Journals (Sweden)

    Ana Glavina

    2017-06-01

    Full Text Available Background Plasma rich in growth factors (PRGF has wider use in many fields of dentistry due to its endogenous biocompatible regenerative potential i.e., their potential to stimulate and accelerate tissue healing and bone regeneration. Aims This review shows the increasing use of PRGF technology in various fields of dentistry. Methods In the last nine years PubMed has been searched in order to find out published articles upon PRGF in dentistry and 36 papers have been included. Results PRGF technology has many advantages with positive clinical and biological outcomes in tissue healing and bone regeneration. Conclusion In order to determine the most effective therapeutic value for patients, further research is required.

  12. Aldosterone as a renal growth factor.

    LENUS (Irish Health Repository)

    Thomas, Warren

    2011-04-05

    Aldosterone regulates blood pressure through its effects on the cardiovascular system and kidney. Aldosterone can also contribute to the development of hypertension that leads to chronic pathologies such as nephropathy and renal fibrosis. Aldosterone directly modulates renal cell proliferation and differentiation as part of normal kidney development. The stimulation of rapidly activated protein kinase cascades is one facet of how aldosterone regulates renal cell growth. These cascades may also contribute to myofibroblastic transformation and cell proliferation observed in pathological conditions of the kidney. Polycystic kidney disease is a genetic disorder that is accelerated by hypertension. EGFR-dependent proliferation of the renal epithelium is a factor in cyst development and trans-activation of EGFR is a key feature in initiating aldosterone-induced signalling cascades. Delineating the components of aldosterone-induced signalling cascades may identify novel therapeutic targets for proliferative diseases of the kidney.

  13. Fibroblast growth factor 23 and bone mineralisation

    Institute of Scientific and Technical Information of China (English)

    Yu-Chen Guo; Quan Yuan

    2015-01-01

    Fibroblast growth factor 23 (FGF23) is a hormone that is mainly secreted by osteocytes and osteoblasts in bone. The critical role of FGF23 in mineral ion homeostasis was first identified in human genetic and acquired rachitic diseases and has been further characterised in animal models. Recent studies have revealed that the levels of FGF23 increase significantly at the very early stages of chronic kidney disease (CKD) and may play a critical role in mineral ion disorders and bone metabolism in these patients. Our recent publications have also shown that FGF23 and its cofactor, Klotho, may play an independent role in directly regulating bone mineralisation instead of producing a systematic effect. In this review, we will discuss the new role of FGF23 in bone mineralisation and the pathophysiology of CKD-related bone disorders.

  14. Neuropeptides as lung cancer growth factors.

    Science.gov (United States)

    Moody, Terry W; Moreno, Paola; Jensen, Robert T

    2015-10-01

    This manuscript is written in honor of the Festschrift for Abba Kastin. I met Abba at a Society for Neuroscience meeting and learned that he was Editor-in-Chief of the Journal Peptides. I submitted manuscripts to the journal on "Neuropeptides as Growth Factors in Cancer" and subsequently was named to the Editorial Advisory Board. Over the past 30 years I have published dozens of manuscripts in Peptides and reviewed hundreds of submitted manuscripts. It was always rewarding to interact with Abba, a consummate professional. When I attended meetings in New Orleans I would sometimes go out to dinner with him at the restaurant "Commanders Palace". When I chaired the Summer Neuropeptide Conference we were honored to have him receive the Fleur Strand Award one year in Israel. I think that his biggest editorial contribution has been the "Handbook of Biologically Active Peptides." I served as a Section Editor on "Cancer/Anticancer Peptides" and again found that it was a pleasure working with him. This review focuses on the mechanisms by which bombesin-like peptides, neurotensin and vasoactive intestinal peptide regulate the growth of lung cancer. Published by Elsevier Inc.

  15. Epidermal growth factor (urogastrone) in human tissues.

    Science.gov (United States)

    Hirata, Y; Orth, D N

    1979-04-01

    Human epidermal growth factor (hEGF), which stimulates the growth of a variety of tissues, was first isolated from mouse submandibular glands, but is also excreted in large amounts (about 50 micrograms/day) in human urine and is probably identical to human beta-urogastrone (hUG), a potent inhibitor of stimulated gastric acid secretion. However, the primary tissue source of hEGF/hUG is as yet unknown. The hEGF/hUG in homogenates of human salivary glands and a wide variety of other endocrine and nonendocrine tissues was extracted by Amberlite CG-50 cation exchange chromatography and immune affinity chromatography using the immunoglobulin fraction of rabbit anti-hEGF serum covalently bound to agarose. The extracts were subjected to homologous hEGF RIA. Immunoreactive hEGF was found in extracts of adult submandibular gland, thyroid gland, duodenum, jejunum, and kidney, but not in several fetal tissues. The tissue immunoreactive hEGF was similar to standard hEGF in terms of immunoreactivity and elution from Sephadex G-50 Fine resin, but its concentrations were very low (1.3-5.5 ng/g wet tissue). Thus, it is not certain that these tissues represent the only source of the large amounts of hEGF/hUG that appear to be filtered by the kidneys each day.

  16. Prognostic impact of placenta growth factor and vascular endothelial growth factor A in patients with breast cancer

    DEFF Research Database (Denmark)

    Maae, Else; Olsen, Dorte Aalund; Steffensen, Karina Dahl;

    2012-01-01

    Placenta growth factor (PlGF) and vascular endothelial growth factor A (VEGF-A) are angiogenic growth factors interacting competitively with the same receptors. VEGF-A is essential in both normal and pathologic conditions, but the functions of PlGF seem to be restricted to pathologic conditions...

  17. Prognostic impact of placenta growth factor and vascular endothelial growth factor A in patients with breast cancer

    DEFF Research Database (Denmark)

    Maae, Else; Olsen, Dorte Aalund; Dahl Steffensen, Karina

    2012-01-01

    Background: Placenta growth factor (PlGF) and vascular endothelial growth factor A (VEGF-A) are angiogenic growth factors interacting competitively with the same receptors. VEGF-A is essential in both normal and pathologic conditions, but the functions of PlGF seem to be restricted to pathologic ...

  18. The Role of Growth Factors in Intestinal Regeneration and Repair in Necrotizing Enterocolitis

    Science.gov (United States)

    Rowland, Kathryn J.; Choi, Pamela M.; Warner, Brad W.

    2013-01-01

    Necrotizing enterocolitis (NEC) is a devastating intestinal disease resulting in major neonatal morbidity and mortality. The pathology is poorly understood, and means of preventing and treating NEC are limited. Several endogenous growth factors have been identified as having important roles in intestinal growth as well as aiding intestinal repair from injury or inflammation. In this review, we will discuss several growth factors as mediators of intestinal regeneration and repair as well as potential therapeutic agents for NEC. PMID:23611614

  19. Factor-structure of economic growth in E-commerce

    Institute of Scientific and Technical Information of China (English)

    吴隽; 刘洪久; 栾天行

    2003-01-01

    In order to analyze the factors having effect on economic growth of E-commerce, the economic growthprocess of E-commerce is divided into three stages; growth stage, stabilization stage and re-growth stage. Thesethree different stages are analysed using several economic growth theories, a set of factor-structure is proposedfor each stage of the economic growth process of E-commerce.

  20. Growth instability due to lattice-induced topological currents in limited-mobility epitaxial growth models.

    Science.gov (United States)

    Kanjanaput, Wittawat; Limkumnerd, Surachate; Chatraphorn, Patcha

    2010-10-01

    The energetically driven Ehrlich-Schwoebel barrier had been generally accepted as the primary cause of the growth instability in the form of quasiregular moundlike structures observed on the surface of thin film grown via molecular-beam epitaxy (MBE) technique. Recently the second mechanism of mound formation was proposed in terms of a topologically induced flux of particles originating from the line tension of the step edges which form the contour lines around a mound. Through large-scale simulations of MBE growth on a variety of crystalline lattice planes using limited-mobility, solid-on-solid models introduced by Wolf-Villain and Das Sarma-Tamborenea in 2+1 dimensions, we show that there exists a topological uphill particle current with strong dependence on specific lattice crystalline structure. Without any energetically induced barriers, our simulations produce spectacular mounds very similar, in some cases, to what have been observed in many recent MBE experiments. On a lattice where these currents cease to exist, the surface appears to be scale invariant, statistically rough as predicted by the conventional continuum growth equation.

  1. Factores de crecimiento IV: Factor de crecimiento epidérmico,Factores estimuladores de colonias, Neurotropinas Growth factors: epidermal growth factor, colony stimulating factors and neurotropins

    Directory of Open Access Journals (Sweden)

    Hilda Norha Jaramillo Londoño

    1999-02-01

    Full Text Available En esta cuarta entrega sobre los factores de crecimiento se revisan el factor de crecimiento epidérmico (EGF, los factores estimuladores de colonias (CSF y las neurotropinas. Como se ha venido presentando en las anteriores entregas, se hace referencia a su estructura bioquímica, su mecanismo de acción, sus efectos biológicos y sus interacciones. Las neurotropinas y el EGF, por tratarse de factores que actúan predominantemente en el microambiente tisular, no pueden manejarse en el contexto de concentraciones circulantes, situación que sí es factible para los CSF. De otro lado, se revisan los mecanismos de las neurotropinas en el sistema nervioso. In this fourth review of growth factors we summarize, as in previous papers, topics related to biochemical structure, mechanisms of action, biological effects and cross-interactions for epidermal growth factor (EGF, colony stimulating factors (CSF and neurotropins. Since the effects of EGF and neurotropins are exerted predominantly at the microenvironment level, they can not be evaluated by means of its circulating levels, a fact that could be possible for CSFs.

  2. Transforming growth factor-β and fibrosis

    Institute of Scientific and Technical Information of China (English)

    Franck Verrecchia; Alain Mauviel

    2007-01-01

    Transforming growth factor-β (TGF-β), a prototype of multifunctional cytokine, is a key regulator of extracellular matrix (ECM) assembly and remodeling. Specifically, TGF-β isoforms have the ability to induce the expression of ECM proteins in mesenchymal cells, and to stimulate the production of protease inhibitors that prevent enzymatic breakdown of the ECM. Elevated TGF-β expression in affected organs, and subsequent deregulation of TGF-β functions, correlates with the abnormal connective tissue deposition observed during the onset of fibrotic diseases. During the last few years, tremendous progress has been made in the understanding of the molecular aspects of intracellular signaling downstream of the TGF-β receptors. In particular, Smad proteins, TGF-β receptor kinase substrates that translocate into the cell nucleus to act as transcription factors, have been studied extensively. The role of Smad3 in the transcriptional regulation of type I collagen gene expression and in the development of fibrosis, demonstrated both in vitro and in animal models with a targeted deletion of Smad3, is of critical importance because it may lead to novel therapeutic strategies against these diseases. This review focuses on the mechanisms underlying Smad modulation of fibrillar collagen expression and how it relates to fibrotic processes.

  3. Growth limitation of three Arctic sea ice algal species

    DEFF Research Database (Denmark)

    Sogaard, D.H.; Hansen, P.J.; Rysgaard, Søren;

    2011-01-01

    results suggest that the chlorophyte and the two diatoms have different tolerance to fluctuations in salinity and pH. The two species of diatoms exhibited maximum growth rates at a salinity of 33, and growth rates at a salinity of 100 were reduced by 50% compared to at a salinity of 33. Growth ceased...... at a salinity of 150. The chlorophyte species was more sensitive to high salinities than the two diatom species. Growth rate of the chlorophyte was greatly reduced already at a salinity of 50 and it could not grow at salinities above 100. At salinity 33 and constant TCO(2) concentration, all species exhibited...... maximal growth rate at pH 8.0 and/or 8.5. The two diatom species stopped growing at pH > 9.5, while the chlorophyte species still was able to grow at a rate which was 1/3 of its maximum growth rate at pH 10. Thus, Chlamydomonas sp. was able to grow at high pH levels in the succession experiment...

  4. Epidermal growth factor: a critical factor in fetal maturation?

    Science.gov (United States)

    Thorburn, G D; Waters, M J; Young, I R; Dolling, M; Buntine, D; Hopkins, P S

    1981-01-01

    Epidermal growth factor (EGF) infused over 3-14 days into fetal sheep of 110-125 days gestation resulted in a number of morphological and endocrine changes. Striking hypertrophy of the skin, wool follicles and their accessory structures was seen, together with a reduction in the ratio of secondary to primary follicles and degenerative changes in wool fibres associated with shedding of fibres. Adrenal, thyroid, liver and kidney weights were increased while thymus weight was decreased. The increase in adrenal size resulted from cortical hypertrophy and was associated with increased cortisol secretion. Thyroid hypertrophy was accompanied by an increase in colloid stores, decreased plasma thyroxine and reverse triiodothyronine (T3) concentrations, unchanged plasma T3 and thyroid-binding globulin and raised thyrotropin (TSH) levels. Thyrotropin receptor affinity and content per gram of tissue were unchanged. Fetal and maternal plasma prolactin and growth hormone levels, and fetal plasma placental lactogen levels, were unchanged, although there was a significant rise in maternal plasma placental lactogen concentrations with high doses of EGF. Other maturational parameters such as switching from fetal to adult haemoglobin and liver glycogen content were unaffected.

  5. Nutritional factors affecting growth of muscle and adipose tissue in ruminants.

    Science.gov (United States)

    Byers, F M

    1982-07-01

    Patterns of tissue growth determine composition of growth, and over intervals of time, these patterns of tissue growth will also be reflected in total tissue accumulated in the animal. Although patterns of tissue growth may be modified by the effects of specific carbon sources through direct impact on lipogenesis, the primary avenue through which nutritional factors regulate or direct protein and fat deposition is through effects of total absorbed energy provided on rates of growth in relation to an animal's daily needs for maintenance and protein growth. Even though mature size and genetic potential establish the maximum upper limits for daily protein growth, other factors determine the extent to which these theoretical limits will ever be achieved. The actual partitioning of absorbed nutrients between protein and fat deposition also depends on other factors, including stage of growth, sex class, hormonal regulation (endogenous and exogenous), and intake of required nutrients. The sex class of an animal establishes different biological limits for bulls, steers, and heifers that are otherwise similar in mature size, genetics, and nutritional adequacy. Also, the use of anabolic agents alters the physiological limit for daily protein growth at the cellular level and allows an animal to deposit protein at rates closer to theoretical genetic limits. Energy that is provided above maintenance and protein growth requirements enhances rates of lipid deposition and accumulation of fat. As a consequence, the rate of growth will direct these tissue responses, and effects of diet, energy level, level of nutrition, and plane of nutrition will impact composition of growth primarily through acceleration of rate of growth above daily limits for protein growth. Changes in tissue storage will impact total body composition to the extent of time and differential in composition of gain and of tissue present.

  6. Arctigenin induced gallbladder cancer senescence through modulating epidermal growth factor receptor pathway.

    Science.gov (United States)

    Zhang, Mingdi; Cai, Shizhong; Zuo, Bin; Gong, Wei; Tang, Zhaohui; Zhou, Di; Weng, Mingzhe; Qin, Yiyu; Wang, Shouhua; Liu, Jun; Ma, Fei; Quan, Zhiwei

    2017-05-01

    Gallbladder cancer has poor prognosis and limited therapeutic options. Arctigenin, a representative dibenzylbutyrolactone lignan, occurs in a variety of plants. However, the molecular mechanisms involved in the antitumor effect of arctigenin on gallbladder cancer have not been fully elucidated. The expression levels of epidermal growth factor receptor were examined in 100 matched pairs of gallbladder cancer tissues. A positive correlation between high epidermal growth factor receptor expression levels and poor prognosis was observed in gallbladder cancer tissues. Pharmacological inhibition or inhibition via RNA interference of epidermal growth factor receptor induced cellular senescence in gallbladder cancer cells. The antitumor effect of arctigenin on gallbladder cancer cells was primarily achieved by inducing cellular senescence. In gallbladder cancer cells treated with arctigenin, the expression level of epidermal growth factor receptor significantly decreased. The analysis of the activity of the kinases downstream of epidermal growth factor receptor revealed that the RAF-MEK-ERK signaling pathway was significantly inhibited. Furthermore, the cellular senescence induced by arctigenin could be reverted by pcDNA-epidermal growth factor receptor. Arctigenin also potently inhibited the growth of tumor xenografts, which was accompanied by the downregulation of epidermal growth factor receptor and induction of senescence. This study demonstrates arctigenin could induce cellular senescence in gallbladder cancer through the modulation of epidermal growth factor receptor pathway. These data identify epidermal growth factor receptor as a key regulator in arctigenin-induced gallbladder cancer senescence.

  7. Role of vascular endothelial growth factor and other growth factors in post-stroke recovery

    Directory of Open Access Journals (Sweden)

    Tanu Talwar

    2014-01-01

    Full Text Available Stroke is a major health problem world-wide and its burden has been rising in last few decades. Until now tissue plasminogen activator is only approved treatment for stroke. Angiogenesis plays a vital role for striatal neurogenesis after stroke. Administration of various growth factors in an early post ischemic phase, stimulate both angiogenesis and neurogenesis and lead to improved functional recovery after stroke. However vascular endothelial growth factors (VEGF is the most potent angiogenic factor for neurovascularization and neurogenesis in ischemic injury can be modulated in different ways and thus can be used as therapy in stroke. In response to the ischemic injury VEGF is released by endothelial cells through natural mechanism and leads to angiogenesis and vascularization. This release can also be up regulated by exogenous administration of Mesenchymal stem cells, by various physical therapy regimes and electroacupuncture, which further potentiate the efficacy of VEGF as therapy in post stroke recovery. Recent published literature was searched using PubMed and Google for the article reporting on methods of up regulation of VEGF and therapeutic potential of growth factors in stroke.

  8. Epidermal Growth Factor Receptor (EGFR) Crosstalks in Liver Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Berasain, Carmen, E-mail: cberasain@unav.es; Latasa, María Ujue; Urtasun, Raquel; Goñi, Saioa; Elizalde, María; Garcia-Irigoyen, Oihane; Azcona, María [Division of Hepatology and Gene Therapy, CIMA, University of Navarra, Pamplona 31008 (Spain); Prieto, Jesús [Division of Hepatology and Gene Therapy, CIMA, University of Navarra, Pamplona 31008 (Spain); CIBERehd, University Clinic, University of Navarra, Pamplona 31080 (Spain); Ávila, Matías A. [Division of Hepatology and Gene Therapy, CIMA, University of Navarra, Pamplona 31008 (Spain)

    2011-05-18

    Hepatocarcinogenesis is a complex multistep process in which many different molecular pathways have been implicated. Hepatocellular carcinoma (HCC) is refractory to conventional chemotherapeutic agents, and the new targeted therapies are meeting with limited success. Interreceptor crosstalk and the positive feedback between different signaling systems are emerging as mechanisms of targeted therapy resistance. The identification of such interactions is therefore of particular relevance to improve therapeutic efficacy. Among the different signaling pathways activated in hepatocarcinogenesis the epidermal growth factor receptor (EGFR) system plays a prominent role, being recognized as a “signaling hub” where different extracellular growth and survival signals converge. EGFR can be transactivated in response to multiple heterologous ligands through the physical interaction with multiple receptors, the activity of intracellular kinases or the shedding of EGFR-ligands. In this article we review the crosstalk between the EGFR and other signaling pathways that could be relevant to liver cancer development and treatment.

  9. Inhibition of placenta growth factor with TB-403

    DEFF Research Database (Denmark)

    Nielsen, Dorte Lisbet; Sengeløv, Lisa

    2012-01-01

    targeting angiogenesis. AREAS COVERED: The data are obtained by searching in the PubMed database. The search terms used included antiangiogenic therapy, TB-403 (RO5323441), placenta growth factor (PlGF) and VEGFR-1 (Flt-1). We review preclinical data concerning the function and inhibition of Pl......GF and summarize data on expression of PlGF in cancer patients. Data from early-phase clinical trials of TB-403 (RO5323441), a monoclonal antibody inhibiting PlGF, are discussed. Future development strategies, therapeutic potentials and limitations of TB-403 are further evaluated. EXPERT OPINION: There are some...... conflicting data on the function of PlGF and the importance of its role in primary tumor growth. Data from some preclinical models of PlGF inhibition and early-phase clinical trials with TB-403 are, however, promising, although the true potential of the drug is yet to be determined. Further clinical...

  10. Gene expression of growth factors and growth factor receptors for potential targeted therapy of canine hepatocellular carcinoma.

    Science.gov (United States)

    Iida, Gentoku; Asano, Kazushi; Seki, Mamiko; Sakai, Manabu; Kutara, Kenji; Ishigaki, Kumiko; Kagawa, Yumiko; Yoshida, Orie; Teshima, Kenji; Edamura, Kazuya; Watari, Toshihiro

    2014-03-01

    The purpose of this study was to evaluate the gene expression of growth factors and growth factor receptors of primary hepatic masses, including hepatocellular carcinoma (HCC) and nodular hyperplasia (NH), in dogs. Quantitative real-time reverse transcriptase-polymerase chain reaction was performed to measure the expression of 18 genes in 18 HCCs, 10 NHs, 11 surrounding non-cancerous liver tissues and 4 healthy control liver tissues. Platelet-derived growth factor-B (PDGF-B), transforming growth factor-α, epidermal growth factor receptor, epidermal growth factor and hepatocyte growth factor were found to be differentially expressed in HCC compared with NH and the surrounding non-cancerous and healthy control liver tissues. PDGF-B is suggested to have the potential to become a valuable ancillary target for the treatment of canine HCC.

  11. Massive three-loop form factor in the planar limit

    CERN Document Server

    Henn, Johannes; Smirnov, Vladimir A; Steinhauser, Matthias

    2016-01-01

    We compute the three-loop QCD corrections to the massive quark-anti-quark-photon form factors $F_1$ and $F_2$ in the large-$N_c$ limit. The analytic results are expressed in terms of Goncharov polylogarithms. This allows for a straightforward numerical evaluation. We also derive series expansions, including power suppressed terms, for three kinematic regions corresponding to small and large invariant masses of the photon momentum, and small velocities of the heavy quarks.

  12. [Stem cells and growth factors in wound healing].

    Science.gov (United States)

    Pikuła, Michał; Langa, Paulina; Kosikowska, Paulina; Trzonkowski, Piotr

    2015-01-02

    Wound healing is a complex process which depends on the presence of various types of cells, growth factors, cytokines and the elements of extracellular matrix. A wound is a portal of entry for numerous pathogens, therefore during the evolution wound healing process has formed very early, being critical for the survival of every individual. Stem cells, which give rise to their early descendants progenitor cells and subsequently differentiated cells, play a specific role in the process of wound healing. Among the most important cells which take part in wound healing the following cells need to be distinguished: epidermal stem cells, dermal precursor of fibroblasts, adipose-derived stem cells as well as bone marrow cells. The activity of these cells is strictly regulated by various growth factors, inter alia epidermal growth factor (EGF), fibroblast growth factor (FGF), platelet-derived growth factor (PDGF), transforming growth factor (TGF), vascular endothelial growth factor (VEGF). Any disorders in functioning of stem cells and biological activity of growth factors may lead to the defects in wound healing, for instance delayed wound healing or creation of hypertrophic scars. Therefore, knowledge concerning the mechanisms of wound healing is extremely essential from clinical point of view. In this review the current state of the knowledge of the role of stem cells and growth factors in the process of wound healing has been presented. Moreover, some clinical aspects of wound healing as well as the possibility of the therapy based on stem cells and growth factors have included.

  13. Stem cells and growth factors in wound healing

    Directory of Open Access Journals (Sweden)

    Michał Pikuła

    2015-01-01

    Full Text Available Wound healing is a complex process which depends on the presence of various types of cells, growth factors, cytokines and the elements of extracellular matrix. A wound is a portal of entry for numerous pathogens, therefore during the evolution wound healing process has formed very early, being critical for the survival of every individual. Stem cells, which give rise to their early descendants progenitor cells and subsequently differentiated cells, play a specific role in the process of wound healing. Among the most important cells which take part in wound healing the following cells need to be distinguished: epidermal stem cells, dermal precursor of fibroblasts, adipose-derived stem cells as well as bone marrow cells. The activity of these cells is strictly regulated by various growth factors, inter alia epidermal growth factor (EGF, fibroblast growth factor (FGF, platelet-derived growth factor (PDGF, transforming growth factor (TGF, vascular endothelial growth factor (VEGF. Any disorders in functioning of stem cells and biological activity of growth factors may lead to the defects in wound healing, for instance delayed wound healing or creation of hypertrophic scars. Therefore, knowledge concerning the mechanisms of wound healing is extremely essential from clinical point of view. In this review the current state of the knowledge of the role of stem cells and growth factors in the process of wound healing has been presented. Moreover, some clinical aspects of wound healing as well as the possibility of the therapy based on stem cells and growth factors have included.

  14. Basic Fibroblast Growth Factor and Fibroblast Growth Factor Receptor-1in Human Meningiomas

    Institute of Scientific and Technical Information of China (English)

    YI Wei; CHEN Jian; Filimon H. Golwa; XUE Delin

    2005-01-01

    The expression of basic fibroblast growth factor (bFGF) and fibroblast growth factor receptor-1 (FGFR-1) in human meningiomas and the relationships between their expression and the tumors' histological features and angiogenesis were investigated by means of immunohistochemical technique. The expression of bFGF and FGFR-1 was detected by antibody of bFGF or FGFR-1.The tumors' angiogenesis was evaluated by microvascular density (MVD) and, which was observed by use of CD34-antibody immunohistochemically. The results showed that there were varied degrees of the expression of bFGF and FGFR-1 proteins in meningiomas. The expression was correlated with the tumors' histological characters and angiogenesis. It was concluded that bFGF and FGFR-1 might play important roles in meningiomas' angiogenesis and proliferation. The expression positive rate of bFGF and FGFR-1 may provide an indication of evaluating the histological and malignant degree of the tumor.

  15. Insulinlike growth factor-binding protein proteolysis an emerging paradigm in insulinlike growth factor physiology.

    Science.gov (United States)

    Fowlkes, J L

    1997-10-01

    In biologic fluids, insulinlike growth factors (IGF-I and IGF-II) are bound to high-affinity insulinlike growth factor binding proteins (IGFBPs) of which seven have now been identified (IGFBPs 1-7). In a variety of biologic fluids, several IGFBPs undergo proteolytic degradation. Such degradation can lead to increased IGF bioavailability at the cell surface, facilitating receptor interactions. Herein, recent data identifying several IGFBP-degrading proteinases and their effects on IGF bioactivity is reviewed, and how IGFBP proteolysis is regulated by IGFs and IGFBPs, as well as how IGFBP cleavage analysis provides insights into the structure and function of IGFBPs, is explored. (Trends Endocrinol Metab 1997;8:299-306). (c) 1997, Elsevier Science Inc.

  16. Immunoreactive transforming growth factor alpha and epidermal growth factor in oral squamous cell carcinomas

    DEFF Research Database (Denmark)

    Therkildsen, M H; Poulsen, Steen Seier; Bretlau, P

    1993-01-01

    , the cells above the basal cell layer were positive for both TGF-alpha and EGF. The same staining pattern was observed in oral mucosa obtained from healthy persons. In moderately to well differentiated carcinomas, the immunoreactivity was mainly confined to the cytologically more differentiated cells, thus......Forty oral squamous cell carcinomas have been investigated immunohistochemically for the presence of transforming growth factor alpha (TGF-alpha) and epidermal growth factor (EGF). The same cases were recently characterized for the expression of EGF-receptors. TGF-alpha was detected...... with a monoclonal mouse antibody and EGF with polyclonal rabbit antiserum. Thirty-five of the tumours were positive for TGF-alpha and 26 of the tumours for EGF. None of the poorly differentiated tumours was positive for EGF, but they all were for TGF-alpha. In sections including normal differentiated oral mucosa...

  17. The population factor in economic growth theory

    NARCIS (Netherlands)

    Meilink, H.A.

    1974-01-01

    Reviews briefly the role of population growth in economic growth theory and makes a few critical remarks on the applied methodology and the underlying assumptions. Emphasis is laid on the possible relationships between population and economic growth in the developing countries, but also Malthus' the

  18. Fetal Growth Restriction at the Limits of Viability

    NARCIS (Netherlands)

    Visser, G. H. A.; Bilardo, Caterina M.; Lees, Christopher

    2014-01-01

    The outcome of early small-for-gestational age and/or intrauterine growth-restricted fetuses is reviewed. In these fetuses the outcome appears to be considerably poorer than that of appropriately grown fetuses and this seems mainly to be caused by intrauterine malnutrition rather than by hypoxemia.

  19. The role of vascular endothelial growth factors and fibroblast growth factors in angiogenesis during otitis media.

    Science.gov (United States)

    Husseman, Jacob; Palacios, Sean D; Rivkin, Alexander Z; Oehl, Heinz; Ryan, Allen F

    2012-01-01

    The middle ear response to otitis media includes transformation and hyperplasia of the mucosal epithelium and subepithelial connective tissue. Significant neovascularization is also noted, which occurs both to support the hypertrophied mucosa and to mediate the increased trafficking of leukocytes. We investigated the role of two known potent angiogenic growth factor families, the fibroblast growth factors (FGFs) and vascular endothelial growth factors (VEGFs), in middle ear mucosal angiogenesis. DNA microarrays were used to evaluate the expression of FGFs and VEGFs, as well as their receptors and unique signaling proteins, in the middle ears of mice undergoing a complete course of acute bacterial otitis media. In addition, a member of each family was introduced to the middle ear submucosal compartment of the normal middle ears of guinea pigs, by a continuous-release osmotic minipump system over 1 week. During the course of bacterial otitis media, a significant regulation of a number of genes important for angiogenesis was identified. Histologic evaluation of middle ear mucosa following micropump infusion of both FGF1 and VEGF-A showed significant angiogenesis at the site of infusion in comparison to control saline infusion. These results support a role for FGFs and VEGFs in the neovascularization of the middle ear mucosa during otitis media, and offer a potential avenue for therapeutic intervention.

  20. [Epidermal growth factor, innovation and safety].

    Science.gov (United States)

    Esquirol Caussa, Jordi; Herrero Vila, Elisabeth

    2015-10-05

    Bioidentical recombinant human epidermal growth factor (rhEGF) is available in concentrations and purity suitable for therapeutic use in long time stable formulations. Beneficial effects in several skin pathologies and lesions have been reported (traumatic and surgical wound healing, laser induced wounds, abnormal scars, keloids, radiation or chemotherapy induced dermatitis, post inflammatory hyperpigmentation or for skin aging damage repairing) and also may be considered for the treatment of several oropharingeal and high gastroesophageal tract mucosa diseases (mouth sores, pharyngeal fistulas, ulcers), and several corneal or conjunctive mucosa lesions. rhEGF has not shown any important side or collateral effects in humans or in laboratory experimentation animals, showing optimal tolerability and safety with continuous use for months. Compounding gives advantages of versatility, individualization, personalization, molecular stability, safety and effectiveness in ideal conditions, showing good tissue penetration, both on intact skin and skin lesions that expose the lower planes to the surface. rhEGF compounds can be considered for prevention or as a treatment of diverse skin and mucosa diseases and conditions through compounding preparations. Copyright © 2014 Elsevier España, S.L.U. All rights reserved.

  1. Isoforms of receptors of fibroblast growth factors.

    Science.gov (United States)

    Gong, Siew-Ging

    2014-12-01

    The breadth and scope of Fibroblast Growth Factor signaling is immense, with documentation of its role in almost every organism and system studied so far. FGF ligands signal through a family of four distinct tyrosine kinase receptors, the FGF receptors (FGFRs). One contribution to the diversity of function and signaling of FGFs and their receptors arises from the numerous alternative splicing variants that have been documented in the FGFR literature. The present review discusses the types and roles of alternatively spliced variants of the FGFR family members and the significant impact of alternative splicing on the physiological functions of five broad classes of FGFR isoforms. Some characterized known regulatory mechanisms of alternative splicing and future directions in studies of FGFR alternative splicing are also discussed. Presence, absence, and/or the combination of specific exons within each FGFR protein impart upon each individual isoform its unique function and expression pattern during normal function and in diseased states (e.g., in cancers and birth defects). A better understanding of the diversity of FGF signaling in different developmental contexts and diseased states can be achieved through increased knowledge of the presence of specific FGFR isoforms and their impact on downstream signaling and functions. Modern high-throughput techniques afford an opportunity to explore the distribution and function of isoforms of FGFR during development and in diseases.

  2. Nerve growth factor enhances sleep in rabbits.

    Science.gov (United States)

    Takahashi, S; Krueger, J M

    1999-04-02

    Nerve growth factor (NGF) elicits rapid-eye-movement sleep (REMS) in cats. Removal of NGF receptor-positive cholinergic basal forebrain neurons inhibits REMS in rats. The aim of the present study was to determine the effects of NGF on sleep and brain temperature (Tbr) in rabbits. Male rabbits were implanted with electroencephalograph (EEG) electrodes, a brain thermistor and an intraventricular (i.c.v.) guide cannula. Rabbits received human beta-NGF i.c.v. (0.01, 0.1, 1.0 or 10 microg] and on a separate day, 25 microl pyrogen-free saline i.c.v. as control. EEG and Tbr were recorded for 23 h after injections. The highest two doses of NGF increased both non-REMS and REMS across the 23-h recording period. REMS was enhanced dose-dependently. Tbr was not affected by any dose of NGF. These results suggest that NGF is involved in both REMS and non-REMS regulation.

  3. The suppression of fibroblast growth factor 2/fibroblast growth factor 4-dependent tumour angiogenesis and growth by the anti-growth factor activity of dextran derivative (CMDB7).

    OpenAIRE

    Bagheri-Yarmand, R.; Kourbali, Y; Mabilat, C; Morère, J. F.; Martin, A; Lu, H; Soria, C; Jozefonvicz, J; Crépin, M

    1998-01-01

    Our previous studies showed that carboxymethyl benzylamide dextran (CMDB7) blocks basic fibroblast growth factor (FGF-2)-dependent cell proliferation of a human breast epithelial line (HBL100), suggesting its potential role as a potent antiangiogenic substance. The derived cell line (HH9), which was transformed with the hst/FGF4 gene, has been shown to be highly proliferative in vitro and to induce angiogenic tumours in nude mice. We show here that CMDB7 inhibits the mitogenic activities of t...

  4. Natural transformation of Campylobacter jejuni occurs beyond limits of growth.

    Directory of Open Access Journals (Sweden)

    Christina S Vegge

    Full Text Available Campylobacter jejuni is a human bacterial pathogen. While poultry is considered to be a major source of food borne campylobacteriosis, C. jejuni is frequently found in the external environment, and water is another well-known source of human infections. Natural transformation is considered to be one of the main mechanisms for mediating transfer of genetic material and evolution of the organism. Given the diverse habitats of C. jejuni we set out to examine how environmental conditions and physiological processes affect natural transformation of C. jejuni. We show that the efficiency of transformation is correlated to the growth conditions, but more importantly that transformation occurs at growth-restrictive conditions as well as in the late stationary phase; hence revealing that growth per se is not required for C. jejuni to be competent. Yet, natural transformation of C. jejuni is an energy dependent process, that occurs in the absence of transcription but requires an active translational machinery. Moreover, we show the ATP dependent ClpP protease to be important for transformation, which possibly could be associated with reduced protein glycosylation in the ClpP mutant. In contrast, competence of C. jejuni was neither found to be involved in DNA repair following DNA damage nor to provide a growth benefit. Kinetic studies revealed that several transformation events occur per cell cycle indicating that natural transformation of C. jejuni is a highly efficient process. Thus, our findings suggest that horizontal gene transfer by natural transformation takes place in various habitats occupied by C. jejuni.

  5. Fibroblast Growth Factors and Vascular Endothelial Growth Factor Promote Cardiac Reprogramming under Defined Conditions

    Directory of Open Access Journals (Sweden)

    Hiroyuki Yamakawa

    2015-12-01

    Full Text Available Fibroblasts can be directly reprogrammed into cardiomyocyte-like cells (iCMs by overexpression of cardiac transcription factors, including Gata4, Mef2c, and Tbx5; however, this process is inefficient under serum-based culture conditions, in which conversion of partially reprogrammed cells into fully reprogrammed functional iCMs has been a major hurdle. Here, we report that a combination of fibroblast growth factor (FGF 2, FGF10, and vascular endothelial growth factor (VEGF, termed FFV, promoted cardiac reprogramming under defined serum-free conditions, increasing spontaneously beating iCMs by 100-fold compared with those under conventional serum-based conditions. Mechanistically, FFV activated multiple cardiac transcriptional regulators and converted partially reprogrammed cells into functional iCMs through the p38 mitogen-activated protein kinase and phosphoinositol 3-kinase/AKT pathways. Moreover, FFV enabled cardiac reprogramming with only Mef2c and Tbx5 through the induction of cardiac reprogramming factors, including Gata4. Thus, defined culture conditions promoted the quality of cardiac reprogramming, and this finding provides new insight into the mechanism of cardiac reprogramming.

  6. LIMITING FACTORS FOR THE DEVELOPMENT OF THE SERBIAN HOSPITALITY INDUSTRY

    Directory of Open Access Journals (Sweden)

    Nikolina Kosar

    2016-12-01

    Full Text Available Heterogeneity and complexity determine multidisciplinary approach to the hospitality research. Identification and analysis of limited hospitality development factors imply very complex scientific approach. Case study methodology is applied on Republic of Serbia, which is transition country and candidate for EU accession. Research results identified key factors which had impact on lag, stagnation and contemporary level of hospitality development. Firstly, way of executed privatization process of hospitality companies in Serbia i.e. only ownership transformation, as part of business transformation, was done (organizational, management, technological, financial and human resources parts of business transformation didn’t implement. Secondly, non-acceptable terms and conditions of credit lines for financing privatization and future business of privatized hospitality companies. Furthermore, buyers of privatized hospitality companies didn’t prepared adequate projections of cash flow and sources of financing (owned and borrowed. Finally, technological development and human resources were result of the first mentioned limited factor. In order to improve business in hospitality industry in transition economies, all stakeholders should be involved. State should improve business environment. Educational institutions should create applicable programs on market. Investors should be ready to invest in technological and human resource development. Banks should implement the best financing practice from headquarters in EU.

  7. [Effect of light and temperature on growth kinetics of Anabaena flosaquae under phosphorus limitation].

    Science.gov (United States)

    Yin, Zhi-Kun; Li, Zhe; Wang, Sheng; Guo, Jin-Song; Xiao, Yan; Liu, Jing; Zhang, Ping

    2015-03-01

    Phosphorus, light and temperature are the key environmental factors leading to algae growth. But the effects of interaction between light and temperature on the growth of Anabaena flosaquae under phosphorus limitation were not well documented in literature. Anabaena flosaquae was selected for the study and lab-scale experiment and simulation were carried out. The results showed that the optimal temperature of Anabaena flosaquae was 20 degrees C under phosphorus limitation when the light intensity was constant, and the optimal light intensity (illuminance) of Anabaena flosaquae was 3 000 lx under phosphorus limitation when the temperature was constant. Based on model fitting and parameter calibration, the optimal temperature and light intensity of Anabaena flosaquae were 21.03 degress C ± 1.55 degrees C and 2 675.12 lx ± 262.93 lx, respectively. These data were close to the actual water environmental condition at the end of spring. Results of this study will provide important foundation for prediction of Anabaena blooms.

  8. Specific antibodies and sensitive immunoassays for the human epidermal growth factor receptors (HER2, HER3, and HER4).

    Science.gov (United States)

    Broughton, Marianne Nordlund; Westgaard, Arne; Paus, Elisabeth; Øijordsbakken, Miriam; Henanger, Karoline J; Naume, Bjørn; Bjøro, Trine

    2017-06-01

    The use of trastuzumab in patients with breast cancer that overexpresses human epidermal growth factor receptor 2 has significantly improved treatment outcomes. However, a substantial proportion of this patient group still experiences progression of the disease after receiving the drug. Evaluation of the changes in expression of the human epidermal growth factor receptors could be of interest. Monoclonal antibodies against the extracellular domain of the human growth factor receptors, 2, 3, and 4, have been raised, and specific and sensitive immunoassays have been established. Sera from healthy individuals (Nordic Reference Interval Project and Database) were analyzed in the human epidermal growth factor receptor 2 assay (N = 805) and the human epidermal growth factor receptor 3 and 4 assays (N = 114), and reference limits were calculated. In addition, sera from 208 individual patients with breast cancer were tested in all three assays. Finally, the human epidermal growth factor receptor 2 assay was compared with a chemiluminescent immunoassay for serum human epidermal growth factor receptor 2/neu. Reference values were as follows: human epidermal growth factor receptor 2, human epidermal growth factor receptor 3, human epidermal growth factor receptor 4, human epidermal growth factor receptor 2 and human epidermal growth factor receptor 3 serum levels between the patients with tissue human epidermal growth factor receptor 2-positive and tissue human epidermal growth factor receptor 2-negative ( p = 0.0026, p = 0.000011) tumors, but not in the serum levels of human epidermal growth factor receptor 4 ( p = 0.054). There was good agreement between the in-house human epidermal growth factor receptor 2 assay and the chemiluminescent immunoassay. Our new specific antibodies for all the three human epidermal growth factor receptors may prove valuable in the development of novel anti-human epidermal growth factor receptor targeted therapies with

  9. Radiation Pressure Acceleration: the factors limiting maximum attainable ion energy

    CERN Document Server

    Bulanov, S S; Schroeder, C B; Bulanov, S V; Esirkepov, T Zh; Kando, M; Pegoraro, F; Leemans, W P

    2016-01-01

    Radiation pressure acceleration (RPA) is a highly efficient mechanism of laser-driven ion acceleration, with with near complete transfer of the laser energy to the ions in the relativistic regime. However, there is a fundamental limit on the maximum attainable ion energy, which is determined by the group velocity of the laser. The tightly focused laser pulses have group velocities smaller than the vacuum light speed, and, since they offer the high intensity needed for the RPA regime, it is plausible that group velocity effects would manifest themselves in the experiments involving tightly focused pulses and thin foils. However, in this case, finite spot size effects are important, and another limiting factor, the transverse expansion of the target, may dominate over the group velocity effect. As the laser pulse diffracts after passing the focus, the target expands accordingly due to the transverse intensity profile of the laser. Due to this expansion, the areal density of the target decreases, making it trans...

  10. Growth factor array fabrication using a color ink jet printer.

    Science.gov (United States)

    Watanabe, Kohei; Miyazaki, Takeshi; Matsuda, Ryoichi

    2003-04-01

    We have developed a novel method for growth factor analysis using a commercial color ink jet printer to fabricate substrata patterned with growth factors. We prepared substrata with insulin printed in a simple pattern or containing multiple areas of varying quantities of printed insulin. When we cultured the mouse myoblast cell line, C2C12, on the insulin-patterned substrata, the cells were grown in the same pattern with the insulin-printed pattern. Cell culture with the latter substrata demonstrated that quantity control of insulin deposition by a color ink jet printer is possible. For further applications, we developed substrata with insulin-like growth factor-I (IGF-I) and basic fibroblast growth factor (bFGF) spotted in 16 different areas in varying combinations and concentrations (growth factor array). With this growth factor array, C2C12 cells were cultured, and the onset of muscle cell differentiation was monitored for the expression of the myogenic regulator myogenin. The ratio of cells expressing myogenin varied with the doses of IGF-I and bFGF in the sections, demonstrating a feasibility of growth factor array fabrication by a color ink jet printer. Since a printer manipulates several colors, this method can be easily applied to multivariate analyses of growth factors and attachment factors affecting cell growth and differentiation. This method may provide a powerful tool for cell biology and tissue engineering, especially for stem cell research in investigating unknown conditions for differentiation.

  11. Insulin-Like Growth Factor-Independent Effects of Growth Hormone on Growth Plate Chondrogenesis and Longitudinal Bone Growth.

    Science.gov (United States)

    Wu, Shufang; Yang, Wei; De Luca, Francesco

    2015-07-01

    GH stimulates growth plate chondrogenesis and longitudinal bone growth directly at the growth plate. However, it is not clear yet whether these effects are entirely mediated by the local expression and action of IGF-1 and IGF-2. To determine whether GH has any IGF-independent growth-promoting effects, we generated (TamCart)Igf1r(flox/flox) mice. The systemic injection of tamoxifen in these mice postnatally resulted in the excision of the IGF-1 receptor (Igf1r) gene exclusively in the growth plate. (TamCart)Igf1r(flox/flox) tamoxifen-treated mice [knockout (KO) mice] and their Igf1r(flox/flox) control littermates (C mice) were injected for 4 weeks with GH. At the end of the 4-week period, the tibial growth and growth plate height of GH-treated KO mice were greater than those of untreated C or untreated KO mice. The systemic injection of GH increased the phosphorylation of Janus kinase 2 and signal transducer and activator of transcription 5B in the tibial growth plate of the C and KO mice. In addition, GH increased the mRNA expression of bone morphogenetic protein-2 and the mRNA expression and protein phosphorylation of nuclear factor-κB p65 in both C and KO mice. In cultured chondrocytes transfected with Igf1r small interfering RNA, the addition of GH in the culture medium significantly induced thymidine incorporation and collagen X mRNA expression. In conclusion, our findings demonstrate that GH can promote growth plate chondrogenesis and longitudinal bone growth directly at the growth plate, even when the local effects of IGF-1 and IGF-2 are prevented. Further studies are warranted to elucidate the intracellular molecular mechanisms mediating the IGF-independent, growth-promoting GH effects.

  12. Future directions with platelet growth factors.

    Science.gov (United States)

    Kuter, D J

    2000-04-01

    Since the purification of thrombopoietin 6 years ago, c-Mpl ligands such as recombinant human thrombopoietin (rhTPO) and pegylated recombinant human megakaryocyte growth and development factor (PEG-rHuMGDF) have undergone extensive clinical investigation. Both recombinant forms have been shown to reduce the thrombocytopenia associated with nonmyeloablative chemotherapy. Several areas of research have been identified for further clinical development of c-Mpl ligands. One future direction is to continue to explore the intravenous route of administration of rhTPO and PEG-rHuMGDF, as well as fusion proteins of interleukin-3-thrombopoietin and thrombopoietin peptide mimetics, which may be as potent as thrombopoietin, but may lack antigenicity. Another focus would be on the use of these molecules in treating non-chemotherapy-induced thrombocytopenia associated with myelodysplastic syndrome (MDS), idiopathic thrombocytopenic purpura (ITP), human immunodeficiency virus (HIV)-related ITP, and liver disease. Additionally, c-Mpl ligands may have a role in improving apheresis yields when administered to normal platelet donors. Considerable data demonstrate the effectiveness of PEG-rHuMGDF in raising the platelet yields in apheresis donors. In the past few years, investigation into the use of thrombopoietin for ex vivo expansion of pluripotent stem cells has been extensive. Last, thrombopoietin may serve as a radioprotectant by preventing radiation-induced apoptosis of pluripotent stem cells. In the coming years, the clinical role of rhTPO, PEG-rHuMGDF, and related molecules such as the thrombopoietin peptide mimetics will probably be established for both chemotherapeutic and nonchemotherapeutic indications.

  13. Nerve growth factor improves ligament healing.

    Science.gov (United States)

    Mammoto, Takeo; Seerattan, Ruth A; Paulson, Kent D; Leonard, Catherine A; Bray, Robert C; Salo, Paul T

    2008-07-01

    Previous work has shown that innervation participates in normal ligament healing. The present study was performed to determine if exogenous nerve growth factor (NGF) would improve the healing of injured ligament by promoting reinnervation, blood flow, and angiogenesis. Two groups of 30 Sprague-Dawley rats underwent unilateral medial collateral ligament transection (MCL). One group was given 10 microg NGF and the other was given PBS via osmotic pump over 7 days after injury. After 7, 14, and 42 days, in vivo blood flow was measured using laser speckle perfusion imaging (LSPI). Morphologic assessments of nerve density, vascularity, and angiogenesis inhibitor production were done in three animals at each time point by immunohistochemical staining for the pan-neuronal marker PGP9.5, the endothelial marker vWF, and the angiogenesis inhibitor thrombospondin-2 (TSP-2). Ligament scar material and structural mechanical properties were assessed in seven rats at each time point. Increased nerve density was promoted by NGF at both 14 and 42 days. Exposure to NGF also led to increased ligament vascularity, as measured by histologic assessment of vWF immunohistochemistry, although LSPI-measured blood flow was not significantly different from controls. NGF treatment also led to decreased expression of TSP-2 at 14 days. Mechanical testing revealed that exposure to NGF increased failure load by 40%, ultimate tensile strength by 55%, and stiffness by 30% at 42 days. There were no detectable differences between groups in creep properties. The results suggest that local application of NGF can improve ligament healing by promoting both reinnervation and angiogenesis, and results in scars with enhanced mechanical properties.

  14. Fibroblast growth factor signaling in metabolic regulation

    Directory of Open Access Journals (Sweden)

    Vera eNies

    2016-01-01

    Full Text Available The prevalence of obesity is a growing health problem. Obesity is strongly associated with several comorbidities, such as non-alcoholic fatty liver disease, certain cancers, insulin resistance and type 2 diabetes, which all reduce life expectancy and life quality. Several drugs have been put forward in order to treat these diseases, but many of them have detrimental side effects. The unexpected role of the family of fibroblast growth factors in the regulation of energy metabolism provides new approaches to the treatment of metabolic diseases, and offers a valuable tool to gain more insight into metabolic regulation. The known beneficial effects of FGF19 and FGF21 on metabolism, together with recently discovered similar effects of FGF1 suggest that FGFs and their derivatives carry great potential as novel therapeutics to treat metabolic conditions. To facilitate the development of new therapies with improved targeting and minimal side effects, a better understanding of the molecular mechanism of action of FGFs is needed.In this review we will discuss what is currently known about the physiological roles of FGF signaling in tissues important for metabolic homeostasis. In addition, we will discuss current concepts regarding their pharmacological properties and effector tissues in the context of metabolic disease. Also the recent progress in the development of FGF variants will be reviewed. Our goal is to provide a comprehensive overview of the current concepts and consensuses regarding FGF signaling in metabolic health and disease, and to provide starting points for the development of FGF-based therapies against metabolic conditions.

  15. Economic growth factors system: theoretical and methodological aspect

    Directory of Open Access Journals (Sweden)

    H.Ya. Hlukha

    2014-03-01

    Full Text Available The aim of the article. The main objective of the article is to create theoretical grounds to build the system of economic growth factors, to modernize their classification, to define exogenous and endogenous factors, to analyze them within the state economic policy structure. The results of the analysis. The article focuses on economic growth factors theoretical studies: - economic growth factors classification characteristics have been highlighted; - various approaches to determine exogenous and endogenous factors have been analyzed; - reflexive and elastic economic growth factors have been determined; - economic policy was given the role of reflective element within the system to ensure economic growth. The system of factors should be considered within the system that ensures economic growth. It comprises two important elements which enlist the economic growth factors system, economic growth rates system and two reflexive elements – the state economic policy and economic growth models system. While analyzing the economic growth factors, their quality and impact upon the economy should be considered. Economic growth depends on the factors, consideration of which is one of the most important aspects of the economic growth theory. Economic growth reasons are the factors that cause this growth. These are phenomena and processes that can increase the production output, improve efficiency and quality. Factors classification completeness and their diversity do not necessarily mean the dead end of the study. Any classification has the sense only if it fulfills the certain function. If we take into account economic growth modeling, factors diversification and their characteristics classification it implies that models are becoming more complex, the range of their parameters expands, however it does not necessarily lead to more accurate prognosis. All the factors have different impact upon the economic development. Their first type is elastic ones

  16. Success factors and limitations of efficient internal communication

    Directory of Open Access Journals (Sweden)

    Dariusz Tworzydło

    2015-03-01

    Full Text Available The article covers the key issues of internal communication within an organization. It highlights the benefits of implementation of transparent communication principles for a company. It identifies objectives and presents selected communication tools. In the article, also guidelines for carrying out research in the context of development of an internal communication strategy can be found. Selected research areas of the process of planning and implementation of strategic assumptions have been presented. Factors limiting effective implementation of an internal communication strategy have been discussed.

  17. Compact or fractal patterns in diffusion limited growth

    Science.gov (United States)

    Ben Amar, Martine

    1993-02-01

    Fractal viscous fingering patterns are observed in an infinite Hele-Shaw cell at long times when the capillary forces become negligible. On the contrary, growth of monocrystals from a punctual seed shows dendrites growing independently in 4 or 6 directions, according to the crystal symmetry. A close comparison of numerical and experimental data explains first the origin of the tip-splitting instability in radial growth and shows that it can be inhibited by the anisotropy of surface tension. Des structures fractales ont été observées en digitations visqueuses en cellule de Hele-Shaw et aux temps longs lorsque les forces capillaires deviennent négligeables. Par opposition, la croissance de monocristaux à partir d'un germe ponctuel fait apparaître des dendrites croissant dans 4 ou 6 directions selon la symétrie cristalline. Une comparaison entre des résultats numériques et des données expérimentales explique l'origine de l'instabilité de dédoublement des pointes en croissance radiale et montre qu'elle peut être supprimée par l'anisotropie cristalline.

  18. Nerve growth factor promotes in vitro proliferation of neural stem cells from tree shrews.

    Science.gov (United States)

    Xiong, Liu-Lin; Chen, Zhi-Wei; Wang, Ting-Hua

    2016-04-01

    Neural stem cells promote neuronal regeneration and repair of brain tissue after injury, but have limited resources and proliferative ability in vivo. We hypothesized that nerve growth factor would promote in vitro proliferation of neural stem cells derived from the tree shrews, a primate-like mammal that has been proposed as an alternative to primates in biomedical translational research. We cultured neural stem cells from the hippocampus of tree shrews at embryonic day 38, and added nerve growth factor (100 μg/L) to the culture medium. Neural stem cells from the hippocampus of tree shrews cultured without nerve growth factor were used as controls. After 3 days, fluorescence microscopy after DAPI and nestin staining revealed that the number of neurospheres and DAPI/nestin-positive cells was markedly greater in the nerve growth factor-treated cells than in control cells. These findings demonstrate that nerve growth factor promotes the proliferation of neural stem cells derived from tree shrews.

  19. Nerve growth factor promotes in vitro proliferation of neural stem cells from tree shrews

    Institute of Scientific and Technical Information of China (English)

    Liu-lin Xiong; Zhi-wei Chen; Ting-hua Wang

    2016-01-01

    Neural stem cells promote neuronal regeneration and repair of brain tissue after injury, but have limited resources and proliferative ability in vivo. We hypothesized that nerve growth factor would promotein vitro proliferation of neural stem cells derived from the tree shrews, a primate-like mammal that has been proposed as an alternative to primates in biomedical translational research. We cultured neural stem cells from the hippocampus of tree shrews at embryonic day 38, and added nerve growth factor (100 μg/L) to the culture medium. Neural stem cells from the hippocampus of tree shrews cultured without nerve growth factor were used as controls. After 3 days, lfuorescence mi-croscopy after DAPI and nestin staining revealed that the number of neurospheres and DAPI/nestin-positive cells was markedly greater in the nerve growth factor-treated cells than in control cells. These ifndings demonstrate that nerve growth factor promotes the proliferation of neural stem cells derived from tree shrews.

  20. Organisational Factors of Rapid Growth of Slovenian Dynamic Enterprises

    Directory of Open Access Journals (Sweden)

    Pšeničny Viljem

    2013-01-01

    Full Text Available The authors provide key findings on the internal and external environmental factors of growth that affect the rapid growth of dynamic enterprises in relation to individual key organisational factors or functions. The key organisational relationships in a growing enterprise are upgraded with previous research findings and identified key factors of rapid growth through qualitative and quantitative analysis based on the analysis of 4,511 dynamic Slovenian enterprises exhibiting growth potential. More than 250 descriptive attributes of a sample of firms from 2011 were also used for further qualitative analysis and verification of key growth factors. On the basis of the sample (the study was conducted with 131 Slovenian dynamic enterprises, the authors verify whether these factors are the same as the factors that were studied in previous researches. They also provide empirical findings on rapid growth factors in relation to individual organisational functions: administration - management - implementation (entrepreneur - manager - employees. Through factor analysis they look for the correlation strength between individual variables (attributes that best describe each factor of rapid growth and that relate to the aforementioned organisational functions in dynamic enterprises. The research findings on rapid growth factors offer companies the opportunity to consider these factors during the planning and implementation phases of their business, to choose appropriate instruments for the transition from a small fast growing firm to a professionally managed growing company, to stimulate growth and to choose an appropriate growth strategy and organisational factors in order to remain, or become, dynamic enterprises that can further contribute to the preservation, growth and development of the Slovenian economy

  1. Pattern of hormone receptors and human epidermal growth factor ...

    African Journals Online (AJOL)

    2015-02-05

    Feb 5, 2015 ... Key words: Breast cancer, human epidermal growth factor receptor 2/neu, immunohistochemistry, ... therapy.[6‑8] Of all these prognostic and predictive factors, ... one of the biggest private medical laboratories in Nigeria.

  2. Have the "mega-journals" reached the limits to growth?

    Science.gov (United States)

    Björk, Bo-Christer

    2015-01-01

    A "mega-journal" is a new type of scientific journal that publishes freely accessible articles, which have been peer reviewed for scientific trustworthiness, but leaves it to the readers to decide which articles are of interest and importance to them. In the wake of the phenomenal success of PLOS ONE, several other publishers have recently started mega-journals. This article presents the evolution of mega-journals since 2010 in terms of article publication rates. The fastest growth seems to have ebbed out at around 35,000 annual articles for the 14 journals combined. Acceptance rates are in the range of 50-70%, and speed of publication is around 3-5 months. Common features in mega-journals are alternative impact metrics, easy reusability of figures and data, post-publication discussions and portable reviews from other journals.

  3. From the Cover: Glutamate antagonists limit tumor growth

    Science.gov (United States)

    Rzeski, Wojciech; Turski, Lechoslaw; Ikonomidou, Chrysanthy

    2001-05-01

    Neuronal progenitors and tumor cells possess propensity to proliferate and to migrate. Glutamate regulates proliferation and migration of neurons during development, but it is not known whether it influences proliferation and migration of tumor cells. We demonstrate that glutamate antagonists inhibit proliferation of human tumor cells. Colon adenocarcinoma, astrocytoma, and breast and lung carcinoma cells were most sensitive to the antiproliferative effect of the N-methyl-D-aspartate antagonist dizocilpine, whereas breast and lung carcinoma, colon adenocarcinoma, and neuroblastoma cells responded most favorably to the -amino-3-hydroxy-5-methyl-4-isoxazole-propionate antagonist GYKI52466. The antiproliferative effect of glutamate antagonists was Ca2+ dependent and resulted from decreased cell division and increased cell death. Morphological alterations induced by glutamate antagonists in tumor cells consisted of reduced membrane ruffling and pseudopodial protrusions. Furthermore, glutamate antagonists decreased motility and invasive growth of tumor cells. These findings suggest anticancer potential of glutamate antagonists.

  4. Epidermal growth factor inhibits cysteamine-induced duodenal ulcers

    DEFF Research Database (Denmark)

    Poulsen, Steen Seier

    1983-01-01

    The effect of the duodenal ulcerogen cysteamine on secretion of epidermal growth factor from Brunner's gland pouches was studied in the rat. Total output of immunoreactive epidermal growth factor was reduced to approximately 55%, compared with controls, 5 h after administration of cysteamine (300...... mg/kg, s.c.). Furthermore, measurements on tissue extracts of the pouches revealed that 5 h after cysteamine treatment, Brunner's glands were depleted of epidermal growth factor. The effect on ulcer development of intraduodenally applied exogenous epidermal growth factor (1 micrograms/kg . h) also...... factor used, when tested on chronic fistula rats, had no effect on acid secretion and did not influence bicarbonate secretion from Brunner's gland pouches. These results demonstrate that epidermal growth factor has a cytoprotective effect on the duodenal mucosa, and it is suggested that inhibition...

  5. Limiting factors for growth and development of domestic mites

    NARCIS (Netherlands)

    Lynden, A.M.T. van; Kort, H.S.M.; Koren, L.G.H.; Pernot, C.E.E.; Bronswijk, J.E.M.H. van

    1996-01-01

    A quarter to half of European households are at risk of health damage due to mites in their home. House dust mites (family Pyroglyphidae) and storage mites (families Acaridae and Gly-cyphagidae) are present; both groups being specific for different ecosystems: house-dust ecosystem of textiles (house

  6. Clinical application of growth factors and cytokines in wound healing.

    Science.gov (United States)

    Barrientos, Stephan; Brem, Harold; Stojadinovic, Olivera; Tomic-Canic, Marjana

    2014-01-01

    Wound healing is a complex and dynamic biological process that involves the coordinated efforts of multiple cell types and is executed and regulated by numerous growth factors and cytokines. There has been a drive in the past two decades to study the therapeutic effects of various growth factors in the clinical management of nonhealing wounds (e.g., pressure ulcers, chronic venous ulcers, diabetic foot ulcers). For this review, we conducted an online search of Medline/PubMed and critically analyzed the literature regarding the role of growth factors and cytokines in the management of these wounds. We focused on currently approved therapies, emerging therapies, and future research possibilities. In this review, we discuss four growth factors and cytokines currently being used on and off label for the healing of wounds. These include granulocyte-macrophage colony-stimulating factor, platelet-derived growth factor, vascular endothelial growth factor, and basic fibroblast growth factor. While the clinical results of using growth factors and cytokines are encouraging, many studies involved a small sample size and are disparate in measured endpoints. Therefore, further research is required to provide definitive evidence of efficacy.

  7. Placenta growth factor and vascular endothelial growth factor B expression in the hypoxic lung

    LENUS (Irish Health Repository)

    Sands, Michelle

    2011-01-25

    Abstract Background Chronic alveolar hypoxia, due to residence at high altitude or chronic obstructive lung diseases, leads to pulmonary hypertension, which may be further complicated by right heart failure, increasing morbidity and mortality. In the non-diseased lung, angiogenesis occurs in chronic hypoxia and may act in a protective, adaptive manner. To date, little is known about the behaviour of individual vascular endothelial growth factor (VEGF) family ligands in hypoxia-induced pulmonary angiogenesis. The aim of this study was to examine the expression of placenta growth factor (PlGF) and VEGFB during the development of hypoxic pulmonary angiogenesis and their functional effects on the pulmonary endothelium. Methods Male Sprague Dawley rats were exposed to conditions of normoxia (21% O2) or hypoxia (10% O2) for 1-21 days. Stereological analysis of vascular structure, real-time PCR analysis of vascular endothelial growth factor A (VEGFA), VEGFB, placenta growth factor (PlGF), VEGF receptor 1 (VEGFR1) and VEGFR2, immunohistochemistry and western blots were completed. The effects of VEGF ligands on human pulmonary microvascular endothelial cells were determined using a wound-healing assay. Results Typical vascular remodelling and angiogenesis were observed in the hypoxic lung. PlGF and VEGFB mRNA expression were significantly increased in the hypoxic lung. Immunohistochemical analysis showed reduced expression of VEGFB protein in hypoxia although PlGF protein was unchanged. The expression of VEGFA mRNA and protein was unchanged. In vitro PlGF at high concentration mimicked the wound-healing actions of VEGFA on pulmonary microvascular endothelial monolayers. Low concentrations of PlGF potentiated the wound-healing actions of VEGFA while higher concentrations of PlGF were without this effect. VEGFB inhibited the wound-healing actions of VEGFA while VEGFB and PlGF together were mutually antagonistic. Conclusions VEGFB and PlGF can either inhibit or potentiate the

  8. Placenta growth factor and vascular endothelial growth factor B expression in the hypoxic lung

    Directory of Open Access Journals (Sweden)

    McLoughlin Paul

    2011-01-01

    Full Text Available Abstract Background Chronic alveolar hypoxia, due to residence at high altitude or chronic obstructive lung diseases, leads to pulmonary hypertension, which may be further complicated by right heart failure, increasing morbidity and mortality. In the non-diseased lung, angiogenesis occurs in chronic hypoxia and may act in a protective, adaptive manner. To date, little is known about the behaviour of individual vascular endothelial growth factor (VEGF family ligands in hypoxia-induced pulmonary angiogenesis. The aim of this study was to examine the expression of placenta growth factor (PlGF and VEGFB during the development of hypoxic pulmonary angiogenesis and their functional effects on the pulmonary endothelium. Methods Male Sprague Dawley rats were exposed to conditions of normoxia (21% O2 or hypoxia (10% O2 for 1-21 days. Stereological analysis of vascular structure, real-time PCR analysis of vascular endothelial growth factor A (VEGFA, VEGFB, placenta growth factor (PlGF, VEGF receptor 1 (VEGFR1 and VEGFR2, immunohistochemistry and western blots were completed. The effects of VEGF ligands on human pulmonary microvascular endothelial cells were determined using a wound-healing assay. Results Typical vascular remodelling and angiogenesis were observed in the hypoxic lung. PlGF and VEGFB mRNA expression were significantly increased in the hypoxic lung. Immunohistochemical analysis showed reduced expression of VEGFB protein in hypoxia although PlGF protein was unchanged. The expression of VEGFA mRNA and protein was unchanged. In vitro PlGF at high concentration mimicked the wound-healing actions of VEGFA on pulmonary microvascular endothelial monolayers. Low concentrations of PlGF potentiated the wound-healing actions of VEGFA while higher concentrations of PlGF were without this effect. VEGFB inhibited the wound-healing actions of VEGFA while VEGFB and PlGF together were mutually antagonistic. Conclusions VEGFB and PlGF can either inhibit or

  9. Molecular characterization of transforming growth factor-ß3.

    NARCIS (Netherlands)

    ten Dijke, P.

    1991-01-01

    Normal tissue homeostasis is controlled by a critical balance of positive and negative modulators. Chapter 2 gives an overview of the molecular aspects of growth control, in particular the role of growth factors and oncogene and anti-oncogene products. Uncontrolled growth of cancer cells may result

  10. Two-dimensional diffusion limited system for cell growth

    Energy Technology Data Exchange (ETDEWEB)

    Hlatky, L.

    1985-11-01

    A new cell system, the ''sandwich'' system, was developed to supplement multicellular spheroids as tumor analogues. Sandwiches allow new experimental approaches to questions of diffusion, cell cycle effects and radiation resistance in tumors. In this thesis the method for setting up sandwiches is described both theoretically and experimentally followed by its use in x-ray irradiation studies. In the sandwich system, cells are grown in a narrow gap between two glass slides. Where nutrients and waste products can move into or out of the local environment of the cells only by diffusing through the narrow gap between the slides. Due to the competition between cells, self-created gradients of nutrients and metabolic products are set up resulting in a layer of cells which resembles a living spheroid cross section. Unlike the cells of the spheroid, however, cells in all regions of the sandwich are visible. Therefore, the relative sizes of the regions and their time-dependent growth can be monitored visually without fixation or sectioning. The oxygen and nutrient gradients can be ''turned off'' at any time without disrupting the spatial arrangement of the cells by removing the top slide of the assembly and subsequently turned back on if desired. Removal of the top slide also provides access to all the cells, including those near the necrotic center, of the sandwich. The cells can then be removed for analysis outside the sandwich system. 61 refs., 17 figs.

  11. Growth-limiting role of endothelial cells in endoderm development.

    Science.gov (United States)

    Sand, Fredrik Wolfhagen; Hörnblad, Andreas; Johansson, Jenny K; Lorén, Christina; Edsbagge, Josefina; Ståhlberg, Anders; Magenheim, Judith; Ilovich, Ohad; Mishani, Eyal; Dor, Yuval; Ahlgren, Ulf; Semb, Henrik

    2011-04-15

    Endoderm development is dependent on inductive signals from different structures in close vicinity, including the notochord, lateral plate mesoderm and endothelial cells. Recently, we demonstrated that a functional vascular system is necessary for proper pancreas development, and that sphingosine-1-phosphate (S1P) exhibits the traits of a blood vessel-derived molecule involved in early pancreas morphogenesis. To examine whether S1P(1)-signaling plays a more general role in endoderm development, S1P(1)-deficient mice were analyzed. S1P(1) ablation results in compromised growth of several foregut-derived organs, including the stomach, dorsal and ventral pancreas and liver. Within the developing pancreas the reduction in organ size was due to deficient proliferation of Pdx1(+) pancreatic progenitors, whereas endocrine cell differentiation was unaffected. Ablation of endothelial cells in vitro did not mimic the S1P(1) phenotype, instead, increased organ size and hyperbranching were observed. Consistent with a negative role for endothelial cells in endoderm organ expansion, excessive vasculature was discovered in S1P(1)-deficient embryos. Altogether, our results show that endothelial cell hyperplasia negatively influences organ development in several foregut-derived organs.

  12. Diffusion-limited growth in bacterial colony formation

    Science.gov (United States)

    Matsushita, Mitsugu; Fujikawa, Hiroshi

    1990-09-01

    Colonies of bacterial species called Bacillus subtilis have been found to grow two-dimensionally and self-similarly on agar plates through diffusion-limited processes in a nutrient concentration field. We obtained a fractal dimension of the colony patterns of D=1.73±0.02, very close to that of the two-dimensional DLA model, and confirmed the existence of the screening effect of protruding main branches against inner ones in a colony, the repulsion between two neighboring colonies and the tendency to grow toward nutrient. These effects are all characteristic of the pattern formation in a Laplacian field. This finding implies the importance of physical properties of the environment for the morphology of bacterial colonies in general.

  13. Vascular Endothelial Growth Factor, diagnostic and therapeutic aspects

    NARCIS (Netherlands)

    Kusumanto, Yoka Hadiani

    2006-01-01

    This thesis focuses on the diagnostic and therapeutic potential of Vascular Endothelial Growth Factor, an angiogenic growth factor. Since the recognition of VEGF’s pivotal role in physiological and pathological angiogenesis research has evolved from cell culture and animal experiments to application

  14. Palifermin (recombinant keratinocyte growth factor-1): a pleiotropic growth factor with multiple biological activities in preventing chemotherapy- and radiotherapy-induced mucositis.

    NARCIS (Netherlands)

    Blijlevens, N.M.A.; Sonis, S.T.

    2007-01-01

    Oral and intestinal mucositis are among the most significant dose-limiting toxic effects of intensive cancer treatment and are associated with adverse clinical and economic outcomes. Palifermin (Kepivancetrade mark), an N-truncated recombinant human keratinocyte growth factor-1, is the first agent t

  15. Epidermal growth factor receptor mutation enhances expression of vascular endothelial growth factor in lung cancer.

    Science.gov (United States)

    Hung, Ming-Szu; Chen, I-Chuan; Lin, Paul-Yann; Lung, Jr-Hau; Li, Ya-Chin; Lin, Yu-Ching; Yang, Cheng-Ta; Tsai, Ying-Huang

    2016-12-01

    Epidermal growth factor receptor (EGFR) activation has been demonstrated to have a critical role in tumor angiogenesis. In the present study, the correlation between EGFR mutations and vascular endothelial growth factor (VEGF) was investigated in lung cancer cell lines and non-small-cell lung cancer (NSCLC) tumor tissues. VEGF levels were significantly increased in culture medium of lung cancer cells and NSCLC tissues with EGFR mutations (H1650 vs. A549, P=0.0399; H1975 vs. A549, Plung cancer cell lines expressing mutant (exon 19 deletion, E746-A750; exon 21 missense mutation, L858R) and wild-type EGFR genes were established. Significantly increased expression of VEGF and stronger inhibitory effects of gefitinib to VEGF expression were observed in exon 19 deletion stable lung cancer cells (exon 19 deletion vs. wild-type EGFR, P=0.0005). The results of the present study may provide an insight into the association of mutant EGFR and VEGF expression in lung cancer, and may assist with further development of targeted therapy for NSCLC in the future.

  16. Efficacy of glial growth factor and nerve growth factor on the recovery of traumatic facial paralysis.

    Science.gov (United States)

    Yildiz, Mucahit; Karlidag, Turgut; Yalcin, Sinasi; Ozogul, Candan; Keles, Erol; Alpay, Hayrettin Cengiz; Yanilmaz, Muhammed

    2011-08-01

    The aim of this study was to assess the effects of Glial growth factor (GGF) and nerve growth factor (NGF) on nerve regeneration in facial nerve anastomosis. In this study, approximately a 1-mm segment was resected from the facial nerve and the free ends were anastomosed. All animals underwent the same surgical procedure and 30 rabbits were grouped randomly in three groups. Control group, the group without any medications; NGF group, the group receiving 250 ng/0.1 ml NGF in the epineurium at the site of anastomosis; GBF group, the group receiving 500 ng/0.1 ml GGF in the epineurium at the site of anastomosis. Medications were given at the time of surgery, and at 24 and 48 h postoperatively. After 2 months, the sites of anastomosis were excised and examined using the electron microscope. It was found that the best regeneration was in the group receiving GGF as compared to the control group in terms of nerve regeneration. Schwann cell and glial cell proliferation were found to be significantly higher in the group receiving GGF as compared to the group receiving NGF. Besides, the number of myelin debris, an indicator of degeneration, was significantly lower in the group with GGF as compared to NGF and control groups (p NGF in order to increase regeneration after nerve anastomosis in experimental traumatic facial nerve paralysis may be a hopeful alternative treatment option in the future. However, further studies on human studies are required to support these results.

  17. Enhanced Phosphoproteomic Profiling Workflow For Growth Factor Signaling Analysis

    DEFF Research Database (Denmark)

    Sylvester, Marc; Burbridge, Mike; Leclerc, Gregory

    2010-01-01

    understanding of pathological processes. In our study we create and integrate data on phosphorylations that are initiated by several growth factor receptors. We present an approach for quantitative, time-resolved phosphoproteomic profiling that integrates the important contributions by phosphotyrosines. Methods...... A549 lung carcinoma cells were used as a model and stimulated with hepatocyte growth factor, epidermal growth factor or fibroblast growth factor. We employed a quick protein digestion workflow with spin filters without using urea. Phosphopeptides in general were enriched by sequential elution from...... in order to maximize identification of peptides as well as localization of phosphorylation sites. Results and Conclusions The combination of SIMAC with phosphotyrosine enrichment leads to a significant increase in identification of potential signaling events in growth factor receptor signaling networks...

  18. Factores de crecimiento II: factores insulinoides de crecimiento Growth factors II: insuline-like growth binging proteins (GFBPs

    Directory of Open Access Journals (Sweden)

    Juan Guillermo Maldonado E.

    1996-03-01

    Full Text Available Se revisan los Factores Insulinoides de Crecimiento, también denominados ";Factores de Crecimiento Similares a la Insulina";, sobre los cuales se dispone de abundante información. Se sintetizan conocimientos recientes sobre dichos factores con énfasis en los siguientes aspectos: estructura bioquímica, concentraciones y sus cambios en los líquidos biológicos, proteínas fijadoras, receptores, mecanismos de acción y efectos biológicos. This review summarizes recent knowledge concerning Insulin.like growth factors I and II, with emphasis on their biochemical structure, concentrations, binding proteins, receptors, mechanisms of action, biological effects, and alterations of their concentrations in biological fluids.

  19. The impact of vascular endothelial growth factor and basic fibroblast growth factor on cardiac fibroblasts grown under altered gravity conditions

    DEFF Research Database (Denmark)

    Ulbrich, Claudia; Leder, Annekatrin; Pietsch, Jessica

    2010-01-01

    Myocardium is very sensitive to gravitational changes. During a spaceflight cardiovascular atrophy paired with rhythm problems and orthostatic intolerance can occur. The aim of this study was to investigate the impact of basic fibroblast growth factor (bFGF) and vascular endothelial growth factor...

  20. Time-dependent release of growth factors from implant surfaces treated with plasma rich in growth factors.

    Science.gov (United States)

    Sánchez-Ilárduya, María Belén; Trouche, Elodie; Tejero, Ricardo; Orive, Gorka; Reviakine, Ilya; Anitua, Eduardo

    2013-05-01

    Plasma rich in growth factors (PRGFs) technology is an autologous platelet-rich plasma approach that provides a pool of growth factors and cytokines that have been shown to increase tissue regeneration and accelerate dental implant osseointegration. In this framework, the spatiotemporal release of growth factors and the establishment of a provisional fibrin matrix are likely to be key aspects governing the stimulation of the early phases of tissue regeneration around implants. We investigated the kinetics of growth factor release at implant surfaces functionalized either with PRGFs or platelet-poor plasma and correlated the results obtained with the morphology of the resulting interfaces. Our main finding is that activation and clot formation favors longer residence times of the growth factors at the interfaces studied, probably due to their retention in the adsorbed fibrin matrix. The concentration of the platelet-derived growth factors above the interfaces becomes negligible after 2-4 days and is significantly higher in the case of activated interfaces than in the case of nonactivated ones, whereas that of the plasmatic hepatocyte growth factor is independent of platelet concentration and activation, and remains significant for up to 9 days. Platelet-rich plasma preparations should be activated to permit growth factor release and thereby facilitate implant surface osseointegration.

  1. TERATOGENIC RESPONSES ARE MODULATED IN MICE LACKING EXPRESSION OF EPIDERMAL GROWTH FACTOR (EGF) AND TRANSFORMING GROWTH FACTOR-ALPHA (TGF)

    Science.gov (United States)

    TITLE:TERATOGENIC RESPONSES ARE MODULATED IN MICE LACKING EXPRESSION OF EPIDERMAL GROWTH FACTOR (EGF) AND TRANSFORMING GROWTH FACTOR-ALPHA (TGF). AUTHORS (ALL): Abbott, Barbara D.1; Best, Deborah S.1; Narotsky, Michael G.1. SPONSOR NAME: None INSTITUTIONS (ALL): 1. Repro Tox ...

  2. TERATOGENIC RESPONSES ARE MODULATED IN MICE LACKING EXPRESSION OF EPIDERMAL GROWTH FACTOR (EGF) AND TRANSFORMING GROWTH FACTOR-ALPHA (TGF)

    Science.gov (United States)

    TITLE:TERATOGENIC RESPONSES ARE MODULATED IN MICE LACKING EXPRESSION OF EPIDERMAL GROWTH FACTOR (EGF) AND TRANSFORMING GROWTH FACTOR-ALPHA (TGF). AUTHORS (ALL): Abbott, Barbara D.1; Best, Deborah S.1; Narotsky, Michael G.1. SPONSOR NAME: None INSTITUTIONS (ALL): 1. Repro Tox ...

  3. Polypeptide growth factors in the course of surgical periodontal treatment.

    Science.gov (United States)

    Pietruska, M D; Pietruski, J K; Stokowska, W

    2000-01-01

    The aim of the study was to evaluate the behaviour of certain polypeptide growth factors in patients with rapidly progressive periodontitis (RPP) during periodontal therapy using alloplastic grafts. Concentrations of epidermal growth factor (EGF), fibroblastic growth factor (FGF), platelet-derived growth factor (PDGF) and transforming growth factor beta (TGF beta) were assayed in blood serum and saliva. Significant differences in the behaviour of growth factors in blood referred to EGF and PDGF. Their mean concentrations in serum of RPP patients were higher both in the preliminary examination and in the final investigation after 3 months compared with control group. However, mean FGF concentrations in serum were significantly higher only in the distant examination. In saliva, the concentrations of EGF, PDGF and FGF were not significantly different compared with control group. Salivary TGF beta in patients with RPP was significantly higher than in controls and increased in the final examination. The differences observed in the concentrations of growth factors in the serum and saliva of patients with RPP indicate that these factors can be involved in inflammation, destruction and regeneration of periodontal tissues.

  4. EDUCATION AS A FACTOR IN ECONOMIC GROWTH.

    Science.gov (United States)

    MACKERTICH, ALEX

    THE VALUE OF AN EDUCATION IN THE ECONOMIC GROWTH OF AN UNDERDEVELOPED COUNTRY (INDIA) WAS INVESTIGATED USING THE CASE STUDY APPROACH. DATA WERE GATHERED AT BOTH THE CENTRAL GOVERNMENT AND VILLAGE LEVELS THROUGH INTERVIEWS WITH INDIAN GOVERNMENT OFFICIALS AND FROM OFFICIAL GOVERNMENT PUBLICATIONS CONCERNING THE NATION'S EDUCATIONAL EFFORTS, AS…

  5. High-growth-factor implosions (HEP4)

    Energy Technology Data Exchange (ETDEWEB)

    Landen, O.L.; Keane, C.J.; Hammel, B.A. [and others

    1996-06-01

    In inertial confinement fusion (ICF), the kinetic energy of an ablating, inward-driven, solid spherical shell is used to compressionally heat the low-density fuel inside. For a given drive, the maximum achievable compressed fuel density and temperature - and hence the maximum neutron production rate depend on the degree of shell isentropy and integrity maintained during the compression. Shell integrity will be degraded by hydrodynamic instability growth of areal density imperfections in the capsule. Surface imperfections on the shell grow as a result of the Richtmyer-Meshkov and Rayleigh-Taylor (RT) instabilities when the shell is accelerated by the ablating lower-density plasma. Perturbations at the outer capsule surface are transferred hydrodynamically to the inner surface, where deceleration of the shell by the lower-density fuel gives rise to further RT growth at the pusher-fuel interface.

  6. ENOD40 encodes a peptide growth factor.

    OpenAIRE

    de Sande, van

    1997-01-01

    Rhizobium bacteria induce the formation of nodules on the roots of leguminous plants. The nodules create the right biological niche for the rhizobia to carry out biological nitrogen fixation by which atmospheric nitrogen is reduced to ammonia. The nodule is a new organ that provides the plant with a nitrogen source for its growth and development. The formation of a nitrogen fixing root nodule is the final result of an extensive collaboration between the plant and the bacterium, which starts w...

  7. Dual chain synthetic heparin-binding growth factor analogs

    Science.gov (United States)

    Zamora, Paul O.; Pena, Louis A.; Lin, Xinhua

    2009-10-06

    The invention provides synthetic heparin-binding growth factor analogs having two peptide chains each branched from a branch moiety, such as trifunctional amino acid residues, the branch moieties separated by a first linker of from 3 to about 20 backbone atoms, which peptide chains bind a heparin-binding growth factor receptor and are covalently bound to a non-signaling peptide that includes a heparin-binding domain, preferably by a second linker, which may be a hydrophobic second linker. The synthetic heparin-binding growth factor analogs are useful as pharmaceutical agents, soluble biologics or as surface coatings for medical devices.

  8. Dual chain synthetic heparin-binding growth factor analogs

    Energy Technology Data Exchange (ETDEWEB)

    Zamora, Paul O. (Gaithersburg, MD); Pena, Louis A. (Poquott, NY); Lin, Xinhua (Plainview, NY)

    2012-04-24

    The invention provides synthetic heparin-binding growth factor analogs having two peptide chains each branched from a branch moiety, such as trifunctional amino acid residues, the branch moieties separated by a first linker of from 3 to about 20 backbone atoms, which peptide chains bind a heparin-binding growth factor receptor and are covalently bound to a non-signaling peptide that includes a heparin-binding domain, preferably by a second linker, which may be a hydrophobic second linker. The synthetic heparin-binding growth factor analogs are useful as pharmaceutical agents, soluble biologics or as surface coatings for medical devices.

  9. Intestinal hormones and growth factors: Effects on the small intestine

    Institute of Scientific and Technical Information of China (English)

    Laurie Drozdowski; Alan BR Thomson

    2009-01-01

    There are various hormones and growth factors which may modify the intestinal absorption of nutrients, and which might thereby be useful in a therapeutic setting,such as in persons with short bowel syndrome. In partⅠ, we focus first on insulin-like growth factors,epidermal and transferring growth factors, thyroid hormones and glucocorticosteroids. Part Ⅱ will detail the effects of glucagon-like peptide (GLP)-2 on intestinal absorption and adaptation, and the potential for an additive effect of GLP2 plus steroids.

  10. Viability and growth of feline preantral follicles in vitro cultured with insulin growth factor and epidermal growth factor supplemented medium.

    Science.gov (United States)

    Alves, A E; Padilha-Nakaghi, L C; Pires-Butler, E A; Apparicio, M; Silva, Nam; Motheo, T F; Vicente, Wrr; Luvoni, G C

    2017-04-01

    In vitro culture of ovarian preantral follicles has emerged as a reproductive technology aimed at obtaining large amount of oocytes for in vitro embryo production. The addition of growth factors (GF) in the in vitro culture of preantral follicles of different species has provided superior results of follicular development, antrum formation and proliferation of granulosa cells. However, there are only few reports regarding the use of these factors on feline preantral follicle in vitro culture. Thus, the aim of this study was to investigate the effect of a combination of IGF-1 and EGF on in vitro viability and growth of preantral follicles and enclosed oocytes collected from domestic cats. A total of 64 follicles characterized by multilayer granulosa cells were isolated and individually cultured for 6 days (T6) in minimum essential medium supplemented with IGF-1+ EGF (100 ng/ml each) or without (control). A higher percentage of follicles were viable after culture with GF than without, and an increase in size when IGF-1+ EGF were added to the medium (170 ± 32.4 μm (T0) vs. 201 ± 22.3 μm (T6); p  .05). These data suggest that the addition of IGF-1 and EGF to the culture medium promotes the in vitro development of preantral follicles of cats. © 2016 Blackwell Verlag GmbH.

  11. Value of measuring serum vascular endothelial growth factor levels in diagnosing acute ischemic stroke.

    Science.gov (United States)

    Dassan, Pooja; Keir, Geoffrey; Jäger, Hans Rolf; Brown, Martin M

    2012-08-01

    It has previously been reported that serum levels of vascular endothelial growth factor are raised after acute ischemic stroke compared to healthy controls. The aim of this prospective study was to ascertain whether serum vascular endothelial growth factor measurements could be used to distinguish between acute ischemic stroke and common stroke mimics in the emergency room. Blood samples were taken on arrival to hospital and daily for six-days, in 44 patients with suspected ischemic stroke (29 acute infarcts and 15 stroke mimics), arriving within 24 h of symptom onset. Vascular endothelial growth factor levels were measured by enzyme-linked immunoassay. The neurological deficit was recorded daily using the National Institute of Health Stroke Scale. Evaluation of infarct volumes was based on diffusion-weighted magnetic resonance imaging. Serum vascular endothelial growth factor levels were significantly raised in acute ischemic stroke patients on the day of symptom onset and at all other time points, compared to healthy controls (P acute ischemic stroke on admission to hospital were only 69% and 73%, respectively. Vascular endothelial growth factor levels were also elevated in four out of 15 stroke mimics, including three patients presenting with postictal paresis. Vascular endothelial growth factor has limited clinical utility in the diagnosis of acute ischemic stroke in the emergency room because levels are also raised in common stroke mimics. Further studies are required to establish the mechanism of vascular endothelial growth factor elevation in postictal paresis. © 2011 The Authors. International Journal of Stroke © 2011 World Stroke Organization.

  12. Methods of limiting willow shrub re-growth after initial removal on fen meadows

    NARCIS (Netherlands)

    Klimkowska, Agata; Dzierza, Paulina; Kotowski, Wiktor; Brzezinska, Kamila

    2010-01-01

    Shrub removal is commonly used for management and restoration of species-rich fen meadows. A common problem after initial shrub cutting of willow is a vigorous re-sprouting and quick re-growth. In this paper we test experimentally what is an effective management option, limiting the re-growth of wil

  13. Methods of limiting willow shrub re-growth after initial removal on fen meadows

    NARCIS (Netherlands)

    Klimkowska, Agata; Dzierza, Paulina; Kotowski, Wiktor; Brzezinska, Kamila

    2010-01-01

    Shrub removal is commonly used for management and restoration of species-rich fen meadows. A common problem after initial shrub cutting of willow is a vigorous re-sprouting and quick re-growth. In this paper we test experimentally what is an effective management option, limiting the re-growth of wil

  14. A fungal growth model fitted to carbon-limited dynamics of Rhizoctonia solani

    NARCIS (Netherlands)

    Jeger, M.J.; Lamour, A.; Gilligan, C.A.; Otten, W.

    2008-01-01

    Here, a quasi-steady-state approximation was used to simplify a mathematical model for fungal growth in carbon-limiting systems, and this was fitted to growth dynamics of the soil-borne plant pathogen and saprotroph Rhizoctonia solani. The model identified a criterion for invasion into

  15. Release kinetics of platelet-derived and plasma-derived growth factors from autologous plasma rich in growth factors.

    Science.gov (United States)

    Anitua, Eduardo; Zalduendo, Mari Mar; Alkhraisat, Mohammad Hamdan; Orive, Gorka

    2013-10-01

    Many studies have evaluated the biological effects of platelet rich plasma reporting the final outcomes on cell and tissues. However, few studies have dealt with the kinetics of growth factor delivery by plasma rich in growth factors. Venous blood was obtained from three healthy volunteers and processed with PRGF-Endoret technology to prepare autologous plasma rich in growth factors. The gel-like fibrin scaffolds were then incubated in triplicate, in a cell culture medium to monitor the release of PDGF-AB, VEGF, HGF and IGF-I during 8 days of incubation. A leukocyte-platelet rich plasma was prepared employing the same technology and the concentrations of growth factors and interleukin-1β were determined after 24h of incubation. After each period, the medium was collected, fibrin clot was destroyed and the supernatants were stored at -80°C until analysis. The growth factor delivery is diffusion controlled with a rapid initial release by 30% of the bioactive content after 1h of incubation and a steady state release when almost 70% of the growth factor content has been delivered. Autologous fibrin matrix retained almost 30% of the amount of the growth factors after 8 days of incubation. The addition of leukocytes to the formula of platelet rich plasma did not increase the concentration of the growth factors, while it drastically increased the presence of pro-inflammatory IL-1β. Further studies employing an in vitro inflammatory model would be interesting to study the difference in growth factors and pro-inflammatory cytokines between leukocyte-free and leukocyte-rich platelet rich plasma.

  16. Cardiac Regeneration using Growth Factors: Advances and Challenges

    Science.gov (United States)

    Rebouças, Juliana de Souza; Santos-Magalhães, Nereide Stela; Formiga, Fabio Rocha

    2016-01-01

    Myocardial infarction is the most significant manifestation of ischemic heart disease and is associated with high morbidity and mortality. Novel strategies targeting at regenerating the injured myocardium have been investigated, including gene therapy, cell therapy, and the use of growth factors. Growth factor therapy has aroused interest in cardiovascular medicine because of the regeneration mechanisms induced by these biomolecules, including angiogenesis, extracellular matrix remodeling, cardiomyocyte proliferation, stem-cell recruitment, and others. Together, these mechanisms promote myocardial repair and improvement of the cardiac function. This review aims to address the strategic role of growth factor therapy in cardiac regeneration, considering its innovative and multifactorial character in myocardial repair after ischemic injury. Different issues will be discussed, with emphasis on the regeneration mechanisms as a potential therapeutic resource mediated by growth factors, and the challenges to make these proteins therapeutically viable in the field of cardiology and regenerative medicine. PMID:27355588

  17. Transient expression of acidic fibroblast growth factor in pea (Pisum ...

    African Journals Online (AJOL)

    Yomi

    2012-03-15

    Mar 15, 2012 ... Key words: Pea plants, acidic fibroblast growth factor, leave injection, plant ... It plays important roles in various stages of development and morphogenesis and also in angiogenesis and wound healing processes (Basilico and.

  18. the significance of epidermal growth factor receptor and survivin ...

    African Journals Online (AJOL)

    2013-01-01

    Jan 1, 2013 ... SURVIVIN EXPRESSION IN BLADDER CANCER TISSUE AND URINE ... Objective: To assess whether epidermal growth factor receptor (EGFR) and survivin ..... lung cancer by the FDA in 2003 (28) and is currently.

  19. The effect of vascular endothelial growth factor-1 expression on ...

    African Journals Online (AJOL)

    Riyad Bendardaf

    2017-02-28

    Feb 28, 2017 ... The effect of vascular endothelial growth factor-1 expression on survival of ... Sharjah, Sharjah, United Arab Emirates; cFaculty of Medicine, Suez Canal University, ..... levels were significantly higher in patients who sub-.

  20. Insulin-like growth factors and pancreas beta cells.

    NARCIS (Netherlands)

    Haeften, T.W. van; Twickler, M.

    2004-01-01

    Abstract Insulin-like growth factors (IGFs) have been implicated in normal growth, and especially foetal pancreas beta-cell development. As low birth weight has been implicated in the development of obesity and type 2 diabetes, much research has evolved into the importance of IGF and their signallin

  1. Insulin-like growth factors and pancreas beta cells

    NARCIS (Netherlands)

    van Haeften, TW; Twickler, TB

    2004-01-01

    Insulin-like growth factors (IGFs) have been implicated in normal growth, and especially foetal pancreas beta-cell development. As low birth weight has been implicated in the development of obesity and type 2 diabetes, much research has evolved into the importance of IGF and their signalling pathway

  2. fibroblast growth factor, MTDH/Astrocyte elevated gene-1 ...

    African Journals Online (AJOL)

    2012-12-05

    Dec 5, 2012 ... Basic fibroblast growth factor (bFGF), also known as. FGF2 is a ..... lung metastases, but does not affect the tumor growth rate and decreases in .... Knox JD, Wolf C, McDaniel K, Clark V, Loriot M, Bowden GT, et al. Matrilysin.

  3. Beta cell proliferation and growth factors

    DEFF Research Database (Denmark)

    Nielsen, Jens Høiriis; Svensson, C; Møldrup, Annette

    1999-01-01

    Formation of new beta cells can take place by two pathways: replication of already differentiated beta cells or neogenesis from putative islet stem cells. Under physiological conditions both processes are most pronounced during the fetal and neonatal development of the pancreas. In adulthood little...... increase in the beta cell number seems to occur. In pregnancy, however, a marked hyperplasia of the beta cells is observed both in rodents and man. Increased mitotic activity has been seen both in vivo and in vitro in islets exposed to placental lactogen (PL), prolactin (PRL) and growth hormone (GH......). Receptors for both GH and PRL are expressed in islet cells and are upregulated during pregnancy. By mutational analysis we have identified different functional domains of the cytoplasmic part of the GH receptor. Thus the mitotic signaling only requires the membrane proximal part of the receptor...

  4. Hypusine modification for growth is the major function of spermidine in Saccharomyces cerevisiae polyamine auxotrophs grown in limiting spermidine.

    Science.gov (United States)

    Chattopadhyay, Manas K; Park, Myung Hee; Tabor, Herbert

    2008-05-06

    Spermidine and its derivative, hypusinated eIF5A, are essential for the growth of Saccharomyces cerevisiae. Very low concentrations of spermidine (10(-8) M) are sufficient for the growth of S. cerevisiae polyamine auxotrophs (spe1Delta, spe2Delta, and spe3Delta). Under these conditions, even though the growth rate is near normal, the internal concentration of spermidine is hypusinated eukaryotic initiation factor 5A (eIF5A) (1/20 of normal), even though there is no change in the amount of total (modified plus unmodified) eIF5A. It is striking that, as intracellular spermidine becomes limiting, an increasing portion of it (up to 54%) is used for the hypusine modification of eIF5A. These data indicate that hypusine modification of eIF5A is a most important function for spermidine in supporting the growth of S. cerevisiae polyamine auxotrophs.

  5. Early diet, insulin-like growth factor-1, growth and later obesity.

    Science.gov (United States)

    Michaelsen, Kim F; Larnkjaer, Anni; Molgaard, Christian

    2013-01-01

    There is increasing evidence that factors in early life are important for the risk of developing overweight and obesity later in childhood. Among the postnatal factors, breastfeeding and complementary feeding are especially interesting because the pattern of these two factors can be changed. Breastfeeding has been shown to reduce the risk of later obesity, although the effect is not substantial. Complementary feeding also seems to play a role. There is some evidence that a high protein intake is associated with a higher risk of obesity later in childhood, whereas a high fat intake during the complementary feeding period does not seem to be a risk factor for later obesity. Thus, the dietary pattern during this period is different from the pattern seen in older children and adults where a high fat intake is associated with a higher risk of obesity and a high protein intake in some studies seems to protect against obesity. A few studies have also suggested that early introduction of complementary foods (before age 4 months) is associated with an increased risk of later obesity. A high weight gain during early life, especially the first 6 months, is associated with a higher risk of developing obesity. However, some studies suggest that weight gain during the 6- to 12-month age period, when complementary feeding is introduced, is not associated with later obesity. Insulin-like growth factor-1 (IGF-1) values and body composition both play a role in the complex pattern between early diet and later obesity, but our present knowledge about how these factors are influenced by diet during infancy is limited. Future studies should include longitudinal data on IGF-1 and body composition during infancy to improve our understanding of how diet in early life can play a role in prevention of later obesity. Copyright © 2013 S. Karger AG, Basel.

  6. Effect of sericin on diabetic hippocampal growth hormone/insulin-like growth factor 1 axis***

    Institute of Scientific and Technical Information of China (English)

    Zhihong Chen; Songhe Yang; Yaqiang He; Chengjun Song; Yongping Liu

    2013-01-01

    Previous studies have shown that sericin extracted from silk cocoon significantly reduces blood glucose levels and protects the nervous system against diabetes mel itus. In this study, a rat type 2 diabetes mel itus model was established by intraperitoneal injection of 25 mg/kg streptozotocin for 3 successive days, fol owing which the rats were treated with sericin for 35 days. After treatment, the blood glucose levels of the diabetic rats decreased significantly, the growth hormone level in serum and its expression in the hippocampus decreased significantly, while the insulin-like growth factor-1 level in serum and insulin-like growth factor-1 and growth hormone receptor expression in the hippocampus increased significantly. The experimental findings indicate that sericin improves disorders of the growth hormone/insulin-like growth factor 1 axis to al eviate hippocampal damage in diabetic rats.

  7. A growth factor phenotype map for ovine preimplantation development.

    Science.gov (United States)

    Watson, A J; Watson, P H; Arcellana-Panlilio, M; Warnes, D; Walker, S K; Schultz, G A; Armstrong, D T; Seamark, R F

    1994-04-01

    The reverse transcription-polymerase chain reaction (RT-PCR) was used to determine the patterns of expression for several growth factor ligand and receptor genes during ovine preimplantation development. Transcripts for insulin-like growth factor (IGF)-I, IGF-II, and the receptors for insulin and IGF-I were detected throughout ovine preimplantation development from the 1-cell to the blastocyst stage. Transforming growth factor alpha (TGF alpha) transcripts were also detected throughout ovine preimplantation development. The mRNAs encoding basic fibroblast growth factor (bFGF) were detected in all stages of the ovine preimplantation embryo, although the relative abundance of this transcript consistently decreased from the 1-cell to the blastocyst stage, suggesting that it may represent a maternal transcript in early sheep embryos. Transcripts encoding ovine trophoblast protein (oTP) were detected only within blastocyst-stage embryos. Primary ovine oviduct cell cultures express the transcripts for IGF-II, IGF-I, TGF alpha, bFGF, TGF beta 1, and the receptors for insulin and IGF-I, suggesting that paracrine growth factor circuits may exist between the oviduct epithelium and the early ovine embryo. Transcripts for insulin, epidermal growth factor (EGF), and nerve growth factor (NGF) were not detected in any stage of the ovine preimplantation embryo or within the oviduct cell preparations. The expression of growth factor transcripts very early in mammalian development would predict that these molecules fulfil a necessary role(s) in supporting the progression of early embryos through the preimplantation interval. Our future efforts will be directed to understanding the nature of these putative regulatory pathways.

  8. Insulin-like growth factor 2

    DEFF Research Database (Denmark)

    Valleh, Mehdi Vafaye; Hyttel, Poul; Rasmussen, Mikkel Aabech;

    2014-01-01

    Intrinsic defects within the embryos, reflected by elevated cell death and low proliferative ability, are considered the most critical factors associated with bovine infertility. The identification of embryonic factors, which are responsible for successful embryo development, is thus critical...... in designing strategies for infertility intervention. In this experiment, the possible mechanisms involved in both blastomere proliferation and regulation of cell death were studied by analysis of relative expression patterns of IGF-II, BCL2-L1, BAK1, and HSP70 in 3 classes of morphological quality groups (e.......g., excellent, good, and poor) of bovine blastocysts produced by IVF. Variation in total blastocyst cell numbers as well as their allocation to inner cell mass and trophectoderm lineages were also determined by differential CDX2 staining. Results showed that transcript levels for IGF-II, BCL2-L1, and the BCL2-L...

  9. Organizational Creativity: A Substantial Factor to Growth

    Directory of Open Access Journals (Sweden)

    Malikeh Beheshtifar

    2013-03-01

    Full Text Available Organizations are increasingly seeking to foster creativity, because it is an important source of organizational innovation as well as competitive advantage. Creativity has been studied from different perspectives and is associated with a number of defining factors and elements. creative organization define as encompassing factors concerning the removal of barriers demonstrating managed innovation, idea evaluation procedures, motivational stimuli, communication procedures, development of idea sources, and evidence of the creative planning process; and organizational creativity is as the creation of a valuable, useful new product, service, idea, procedure, or process by individuals working together in a complex social system. The creative climate encourages people to generate new ideas and helps the organization to grow and increase its efficiency and at the same time it enables members to generate and implement creative ideas more effectively.

  10. Lifetime growth in wild meerkats: incorporating life history and environmental factors into a standard growth model.

    Science.gov (United States)

    English, Sinéad; Bateman, Andrew W; Clutton-Brock, Tim H

    2012-05-01

    Lifetime records of changes in individual size or mass in wild animals are scarce and, as such, few studies have attempted to model variation in these traits across the lifespan or to assess the factors that affect them. However, quantifying lifetime growth is essential for understanding trade-offs between growth and other life history parameters, such as reproductive performance or survival. Here, we used model selection based on information theory to measure changes in body mass over the lifespan of wild meerkats, and compared the relative fits of several standard growth models (monomolecular, von Bertalanffy, Gompertz, logistic and Richards). We found that meerkats exhibit monomolecular growth, with the best model incorporating separate growth rates before and after nutritional independence, as well as effects of season and total rainfall in the previous nine months. Our study demonstrates how simple growth curves may be improved by considering life history and environmental factors, which may be particularly relevant when quantifying growth patterns in wild populations.

  11. The neglected role of insulin-like growth factors in the maternal circulation regulating fetal growth.

    Science.gov (United States)

    Sferruzzi-Perri, A N; Owens, J A; Pringle, K G; Roberts, C T

    2011-01-01

    Maternal insulin-like growth factors (IGFs) play a pivotal role in modulating fetal growth via their actions on both the mother and the placenta. Circulating IGFs influence maternal tissue growth and metabolism, thereby regulating nutrient availability for the growth of the conceptus. Maternal IGFs also regulate placental morphogenesis, substrate transport and hormone secretion, all of which influence fetal growth either via indirect effects on maternal substrate availability, or through direct effects on the placenta and its capacity to supply nutrients to the fetus. The extent to which IGFs influence the mother and/or placenta are dependent on the species and maternal factors, including age and nutrition. As altered fetal growth is associated with increased perinatal morbidity and mortality and a greater risk of developing degenerative diseases in adult life, understanding the role of maternal IGFs during pregnancy is essential in order to identify mechanisms underlying altered fetal growth and offspring programming.

  12. Rate limits in silicon sheet growth - The connections between vertical and horizontal methods

    Science.gov (United States)

    Thomas, Paul D.; Brown, Robert A.

    1987-01-01

    Meniscus-defined techniques for the growth of thin silicon sheets fall into two categories: vertical and horizontal growth. The interactions of the temperature field and the crystal shape are analyzed for both methods using two-dimensional finite-element models which include heat transfer and capillarity. Heat transfer in vertical growth systems is dominated by conduction in the melt and the crystal, with almost flat melt/crystal interfaces that are perpendicular to the direction of growth. The high axial temperature gradients characteristic of vertical growth lead to high thermal stresses. The maximum growth rate is also limited by capillarity which can restrict the conduction of heat from the melt into the crystal. In horizontal growth the melt/crystal interface stretches across the surface of the melt pool many times the crystal thickness, and low growth rates are achievable with careful temperature control. With a moderate axial temperature gradient in the sheet a substantial portion of the latent heat conducts along the sheet and the surface of the melt pool becomes supercooled, leading to dendritic growth. The thermal supercooling is surpressed by lowering the axial gradient in the crystal; this configuration is the most desirable for the growth of high quality crystals. An expression derived from scaling analysis relating the growth rate and the crucible temperature is shown to be reliable for horizontal growth.

  13. Maximum Growth Potential and Periods of Resource Limitation in Apple Tree.

    Science.gov (United States)

    Reyes, Francesco; DeJong, Theodore; Franceschi, Pietro; Tagliavini, Massimo; Gianelle, Damiano

    2016-01-01

    Knowledge of seasonal maximum potential growth rates are important for assessing periods of resource limitations in fruit tree species. In this study we assessed the periods of resource limitation for vegetative (current year stems, and woody biomass) and reproductive (fruit) organs of a major agricultural crop: the apple tree. This was done by comparing relative growth rates (RGRs) of individual organs in trees with reduced competition for resources to trees grown under standard field conditions. Special attention was dedicated to disentangling patterns and values of maximum potential growth for each organ type. The period of resource limitation for vegetative growth was much longer than in another fruit tree species (peach): from late May until harvest. Two periods of resource limitation were highlighted for fruit: from the beginning of the season until mid-June, and about 1 month prior to harvest. By investigating the variability in individual organs growth we identified substantial differences in RGRs among different shoot categories (proleptic and epicormic) and within each group of monitored organs. Qualitatively different and more accurate values of growth rates for vegetative organs, compared to the use of the simple compartmental means, were estimated. Detailed, source-sink based tree growth models, commonly in need of fine parameter tuning, are expected to benefit from the results produced by these analyses.

  14. An immunologic approach to induction of epidermal growth factor deficiency

    DEFF Research Database (Denmark)

    Raaberg, Lasse; Nexø, Ebba; Poulsen, Steen Seier;

    1995-01-01

    Epidermal growth factor (EGF) in pharmacologic doses is able to induce growth and development in the fetus and the newborn. To investigate the opposite situation, the effects of insufficient amounts of EGF during development, we wanted to establish an in vivo model with a state of EGF deficiency......(-9) mol/L. The antibodies recognized purified EGF from the submandibular glands (6 kD) and from urine (45 kD) and further native EGF in saliva and urine. The cross-reactivity toward transforming growth factor-alpha was below 3%. Binding of EGF by antibodies inhibited its binding to the EGF...

  15. Neutrophil biology and the next generation of myeloid growth factors.

    Science.gov (United States)

    Dale, David C

    2009-01-01

    Neutrophils are the body's critical phagocytic cells for defense against bacterial and fungal infections; bone marrow must produce approximately 10 x 10(9) neutrophils/kg/d to maintain normal blood neutrophil counts. Production of neutrophils depends on myeloid growth factors, particularly granulocyte colony-stimulating factor (G-CSF). After the original phase of development, researchers modified these growth factors to increase their size and delay renal clearance, increase their biologic potency, and create unique molecules for business purposes. Pegylated G-CSF is a successful product of these efforts. Researchers have also tried to identify small molecules to serve as oral agents that mimic the parent molecules, but these programs have been less successful. In 2006, the European Medicines Agency established guidelines for the introduction of new biologic medicinal products claimed to be similar to reference products that had previously been granted marketing authorization in the European community, called bio-similars. Globally, new and copied versions of G-CSF and other myeloid growth factors are now appearing. Some properties of the myeloid growth factors are similar to other agents, offering opportunities for the development of alternative drugs and treatments. For example, recent research shows that hematopoietic progenitor cells can be mobilized with a chemokine receptor antagonist, chemotherapy, G-CSF, and granulocyte macrophage colony-stimulating factor. Advances in neutrophil biology coupled with better understanding and development of myeloid growth factors offer great promise for improving the care of patients with cancer and many other disorders.

  16. Interplay between pro-inflammatory cytokines and growth factors in depressive illnesses

    Directory of Open Access Journals (Sweden)

    Marie-Claude eAudet

    2013-05-01

    Full Text Available The development of depressive disorders had long been attributed to monoamine variations, and pharmacological treatment strategies likewise focused on methods of altering monoamine availability. However, the limited success achieved by treatments that altered these processes spurred the search for alternative mechanisms and treatments. Here we provide a brief overview concerning a possible role for pro-inflammatory cytokines and growth factors in major depression, as well as the possibility of targeting these factors in treating this disorder. The data suggest that focusing on one or another cytokine or growth factor might be counterproductive, especially as these factors may act sequentially or in parallel in affecting depressive disorders. It is also suggested that cytokines and growth factors might be useful biomarkers for individualized treatments of depressive illnesses.

  17. Endothelial heparan sulfate 6-O-sulfation levels regulate angiogenic responses of endothelial cells to fibroblast growth factor 2 and vascular endothelial growth factor

    NARCIS (Netherlands)

    Ferreras, C.; Rushton, G.; Cole, C.L.; Babur, Muhammad; Telfer, B.A.; Kuppevelt, A.H. van; Gardiner, J.M.; Williams, K.J.; Jayson, G.C.; Avizienyte, E.

    2012-01-01

    Fibroblast growth factor 2 (FGF2) and vascular endothelial growth factor 165 (VEGF(165)) are potent pro-angiogenic growth factors that play a pivotal role in tumor angiogenesis. The activity of these growth factors is regulated by heparan sulfate (HS), which is essential for the formation of FGF2/FG

  18. Inducing effects of hepatocyte growth factor on the expression of vascular endothelial growth factor in human colorectal carcinoma cells through MEK and PI3K signaling pathways

    Institute of Scientific and Technical Information of China (English)

    ZHANG Yu-hua; WEI Wei; XU Hao; WANG Yan-yan; WU Wen-xi

    2007-01-01

    Background Vascular endothelial growth factor plays a key role in human colorectal carcinoma invasion and metastasis. However, the regulation mechanism remains unknown. Recent studies have shown that several cytokines can regulate the expression of vascular endothelial growth factor in tumor cells. In this study, we investigated whether hepatocyte growth factor can regulate the expression of vascular endothelial growth factor in colorectal carcinoma cells.Methods Hepatocyte growth factor and vascular endothelial growth factor in human serum were measured by ELISA.The mRNA level of vascular endothelial growth factor was analyzed by reverse transcription-PCR. Western blot assay was performed to evaluate levels of c-Met and several other proteins involved in the MAPK and PI3K signaling pathways in colorectal carcinoma cells.Results Serum hepatocyte growth factor and vascular endothelial growth factor were significantly increased in colorectal carcinoma subjects. In vitro extraneous hepatocyte growth factor markedly increased protein and mRNA levels of vascular endothelial growth factor in colorectal carcinoma cells. Hepatocyte growth factor induced phosphorylation of c-Met, ERK1/2 and AKT in a dose-dependent manner. Specific inhibitors on MEK and PI3K inhibited the hepatocyte growth factor-induced expression of vascular endothelial growth factor in colorectal carcinoma cells.Conclusion This present study indicates that hepatocyte growth factor upregulates the expression of vascular endothelial growth factor in colorectal carcinoma cells via the MEK/ERK and PI3K/AKT signaling pathways.

  19. EXPRESSION OF EPIDERMAL GROWTH FACTOR, TRANSFORMING GROWTH FACTOR-a AND THEIR RECEPTOR IN HUMAN PITUITARY TUMORS

    Institute of Scientific and Technical Information of China (English)

    ZHANG; Long

    2001-01-01

    [1]LIU Xu-wen, FU Pei-yu, GAO Zhi-xian. Expression of epidermal growth factor receptors in human glioma [J]. Chin J Neurosurgery 1998; 14:71.[2]Wong AJ, Ruppert JM, Bigner SH, et al. Structural alterations of the epidermal growth factor receptor gene in human gliomas [J]. Proc Natl Acad Sci USA 1992; 89:4309.[3]Webster J, Ham J, Bevan JS. Preliminary characterization of growth factors secreted by human pituitary tumors [J]. J Clin Endocrinol Metab 1991; 72:687.[4]Klibanski A. Nonsecreting pituitary tumors [J]. Endocrinol Metab Clin North Am 1987; 16:793.[5]LeRiche VK, Asa SL, Ezzat S. Epidermal growth factor and its receptor (EGF-R) in human pituitary adenomas: EGF-R correlates with tumor aggressiveness [J]. J Clin Endocrinol Metab 1996; 81:656.

  20. LU分解的增长因子%ON GROWTH FACTORS OF THE LU FACTORIZATION

    Institute of Scientific and Technical Information of China (English)

    魏木生; 刘巧华

    2008-01-01

    In this article, we derive upper bounds of different growth factors for the LU factorization, which are dominated by A11(k)-1A12(k),A21(k)A11(k)-1, where A11(k), A12(k), A21(k), A22(k) are sub-matrices of A. We also derive upper bounds of growth factors for the Cholesky factorization. Numerical examples are presented to verify our findings.

  1. Epidermal growth factor induces changes of interaction between epidermal growth factor receptor and actin in intact cells

    Institute of Scientific and Technical Information of China (English)

    Wei Song; Haixing Xuan; Qishui Lin

    2008-01-01

    The epidermal growth factor receptor (EGFR) is a cyto-skeleton-binding protein. Although purified EGFR can interact with actins in vitro and normally at least 10% of EGFR exist in the insoluble cytoskeleton fraction of A431 cells, interaction of cytosolic EGFR with actin can only be visualized by fluorescence resonance energy transfer when epidermal growth factor presents in the cell medium. Results indicate that the correct orientation between EGFR and actin is important in the signal transduction process.

  2. Factors affecting growth and pigmentation of Penicillium caseifulvum

    DEFF Research Database (Denmark)

    Suhr, Karin Isabel; Haasum, I.; Steenstrup, L.D.;

    2002-01-01

    Color formation, metabolite production and growth of Penicillium caseifulvum were studied in order to elucidate factors contributing to. yellow discoloration of Blue Cheese caused by the mold. A screening experiment was set up to study the effect of pH, concentration of salt (NaCl), P, K, N, S, Mg...... and the trace metals Fe, Cu, Zn, Mn on yellow color formation, metabolite production and mold growth. Multivariate statistical analysis showed that the most important factor affecting yellow color formation was pH. The most pronounced formation of yellow color, supported by highest amount of colored metabolites......, appeared at low pH (pH 4). Mold growth was not correlated to the yellow color formation. Salt concentration was the most important factor affecting mold growth and length of lag phase. Production of secondary metabolites was strongly influenced by both pH and salt concentration. The screening results were...

  3. Growth of juvenile steelhead Oncorhynchus mykiss under size-selective pressure limited by seasonal bioenergetic and environmental constraints

    Science.gov (United States)

    Thompson, Jamie N.; Beauchamp, David A.

    2016-01-01

    Increased freshwater growth of juvenile steelhead Oncorhynchus mykiss improved survival to smolt and adult stages, thus prompting an examination of factors affecting growth during critical periods that influenced survival through subsequent life stages. For three tributaries with contrasting thermal regimes, a bioenergetics model was used to evaluate how feeding rate and energy density of prey influenced seasonal growth and stage-specific survival of juvenile O. mykiss. Sensitivity analysis examined target levels for feeding rate and energy density of prey during the growing season that improved survival to the smolt and adult stages in each tributary. Simulated daily growth was greatest during warmer months (1 July to 30 September), whereas substantial body mass was lost during cooler months (1 December to 31 March). Incremental increases in annual feeding rate or energy density of prey during summer broadened the temperature range at which faster growth occurred and increased the growth of the average juvenile to match those that survived to smolt and adult stages. Survival to later life stages could be improved by increasing feeding rate or energy density of the diet during summer months, when warmer water temperatures accommodated increased growth potential. Higher growth during the summer period in each tributary could improve resiliency during subsequent colder periods that lead to metabolic stress and weight loss. As growth and corresponding survival rates in fresh water are altered by shifting abiotic regimes, it will be increasingly important for fisheries managers to better understand the mechanisms affecting growth limitations in rearing habitats and what measures might maintain or improve growth conditions and survival.

  4. Growth of juvenile steelhead Oncorhynchus mykiss under size-selective pressure limited by seasonal bioenergetic and environmental constraints.

    Science.gov (United States)

    Thompson, J N; Beauchamp, D A

    2016-09-01

    Increased freshwater growth of juvenile steelhead Oncorhynchus mykiss improved survival to smolt and adult stages, thus prompting an examination of factors affecting growth during critical periods that influenced survival through subsequent life stages. For three tributaries with contrasting thermal regimes, a bioenergetics model was used to evaluate how feeding rate and energy density of prey influenced seasonal growth and stage-specific survival of juvenile O. mykiss. Sensitivity analysis examined target levels for feeding rate and energy density of prey during the growing season that improved survival to the smolt and adult stages in each tributary. Simulated daily growth was greatest during warmer months (1 July to 30 September), whereas substantial body mass was lost during cooler months (1 December to 31 March). Incremental increases in annual feeding rate or energy density of prey during summer broadened the temperature range at which faster growth occurred and increased the growth of the average juvenile to match those that survived to smolt and adult stages. Survival to later life stages could be improved by increasing feeding rate or energy density of the diet during summer months, when warmer water temperatures accommodated increased growth potential. Higher growth during the summer period in each tributary could improve resiliency during subsequent colder periods that lead to metabolic stress and weight loss. As growth and corresponding survival rates in fresh water are altered by shifting abiotic regimes, it will be increasingly important for fisheries managers to better understand the mechanisms affecting growth limitations in rearing habitats and what measures might maintain or improve growth conditions and survival. © 2016 The Fisheries Society of the British Isles.

  5. Factors Affecting Growth of Pinus radiata in Chile

    Science.gov (United States)

    Alvarez-Munoz, Jose Santos

    (2005--2009) for a network of permanent sample plots in Pinus radiata plantations in Chile. In 2009, we calculated LAI from ground measurements using LI-COR LAI-2000 and TRAC instruments on each one hectare plot. These values of LAI were regressed against Simple Ratio (SR), Normalized Difference Vegetation Index (NDVI) and Reduced Simple Ratio (RSR), derived from the TM 2009 data. Linear relationships were strong with R2 values of 0.65 for SR, 0.61 for NDVI and 0.67 for RSR. Using the RSR relationship, LAI values were estimated for the network of permanent sample plots of Pinus radiata plantations over the whole period. For project 3, we examined environmental factors affecting growth rates of Pinus radiata in Chile. Water availability (as affected by precipitation, soil water holding capacity, and potential evapotranspiration) appeared to be the factor most limiting to leaf area and growth. Maximum growing season temperature also negatively affected growth. Sites with highest productivities had the lowest annual water deficits and the most productive sites used water and light more efficiently. Good sites produced 1.6 as compared to 0.49 kg of wood per m3 of evapotranspired water for less productive sites. In addition, productive stands produced 0.5 as compared to 0.31 g of wood per MJ for less productive sites.

  6. Growth factors: first part Factores de crecimiento I

    Directory of Open Access Journals (Sweden)

    Hilda Norha Jaramillo Londoño

    1996-02-01

    Full Text Available

    Los factores de crecimiento tienen como función activar o inhibir la transcripción génica; es así como la cascada enzimática que se inicia con la activación de los receptores de la membrana citoplasmática, ya sean de tipo segundo mensajero o catalíticos, tiene como efecto final la fosforilación de proteínas, las cuales pueden ser: 1 enzimas que intervienen en las vías metabólicas; 2 proteínas promotoras de la transcripción de genes o, por el contrario, represoras de los mismos (31,32; en algunos casos el efecto final consiste en la transcripción de protooncogenes (33 cuyos productos pueden ser otro factor de crecimiento o receptores para éstos (16; 3 algunos factores de crecimiento ejercen sus efectos sobre los eventos postranscripcionales y postraslacionales (23.

    Los Factores de Crecimiento, incluyendo las citoquinas, representan un número muy grande de polipéptidos, glucoproteínas y otras moléculas relacionadas. Todos ellos promueven la proliferación, la diferenciación y las funciones especializadas de casi cualquier tipo de célula. Juegan un papel importante mediando los modos paracrino, autocrino y endocrino de comunicación. En esta primera parte de una serie se definen y clasifican los factores de crecimiento; para la clasificación se proponen diversos sistemas basados en el período de desarrollo del individuo en que actúan, en el punto crítico del ciclo celular sobre el que ejercen su acción y en los efectos fisiológicos que producen; se discuten, además, someramente, la composición química, los mecanismos de acción y las funciones de estas sustancias.

  7. Step driven competitive epitaxial and self-limited growth of graphene on copper surface

    Directory of Open Access Journals (Sweden)

    Lili Fan

    2011-09-01

    Full Text Available The existence of surface steps was found to have significant function and influence on the growth of graphene on copper via chemical vapor deposition. The two typical growth modes involved were found to be influenced by the step morphologies on copper surface, which led to our proposed step driven competitive growth mechanism. We also discovered a protective role of graphene in preserving steps on copper surface. Our results showed that wide and high steps promoted epitaxial growth and yielded multilayer graphene domains with regular shape, while dense and low steps favored self-limited growth and led to large-area monolayer graphene films. We have demonstrated that controllable growth of graphene domains of specific shape and large-area continuous graphene films are feasible.

  8. Insulin-like growth factor system in amyotrophic lateral sclerosis

    NARCIS (Netherlands)

    Wilczak, N; de Keyser, J; Cianfarani, S; Clemmons, DR; Savage, MO

    2005-01-01

    Insulin-like growth factor-I (IGF-I) is a neurotrophic factor with insulin-like metabolic activities, and possesses potential clinical applications, particularly in neurodegenerative disorders. Amyotrophic lateral sclerosis (ALS) is a chronic progressive devastating disorder of the central nervous s

  9. Effects of Electromagnetic Field and Basic Fibroblast Growth Factor on Osteoblast's Growth

    Institute of Scientific and Technical Information of China (English)

    GUOYong; ZHANGXi-zheng; WANGHao; LIBin; LIRui-xin; WUJin-hui; ZHAOYun-shan; WUJi-min

    2004-01-01

    Osteoblasts of rat cultured in vitro were stimulated with pulsed 50 Hz electromagnetic field and basic fibroblast growth factor(bFGF). The MTT method, flow cytometry and histochemistry staining were used to detect cell proliferation, cell cycle and alkaline phosphatase. The results indicated : after stimulated by 1 mT electromagnetic field, the cells are more abundant,have more S phase percentages, 2 mT electromagnetic field have no evident effect on cells' growth;compared with electromagnetic field, the cells stimulated by bFGF are more abundant and have larger S phase ratios. Electromagnetic field and bFGF have no effect on cells, alkaline phosphatase. Therefore ,we concluded that electromagnetic field can enhance osteoblasts growth like some growth factor such as basic fibroblast growth factor, and the osteoblasts', characteristics was not changed.

  10. Mobile carbohydrates in Himalayan treeline trees I. Evidence for carbon gain limitation but not for growth limitation.

    Science.gov (United States)

    Li, Mai-He; Xiao, Wen-Fa; Wang, San-Gen; Cheng, Gen-Wei; Cherubini, Paolo; Cai, Xaio-Hu; Liu, Xing-Liang; Wang, Xiao-Dan; Zhu, Wan-Ze

    2008-08-01

    To test whether the altitudinal distribution of trees is determined by a carbon shortage or an insufficient sugar fraction (sugar:starch ratio) in treeline trees, we studied the status of nonstructural carbohydrates (NSC) and their components (total soluble sugars and starch) in Abies fabri (Mast.) Craib and Picea balfouriana var. hirtella Rehd. et Wils. trees along three elevational gradients, ranging from lower elevations to the alpine treeline, on the eastern edge of the Tibetan Plateau. For comparison, we investigated a low-altitude species (Tsuga yunnanensis (Franch.) Pritz.) which served as a warm-climate reference because it is distributed in closed montane forests below 3100 m a.s.l. in the study area. The carbon status of T. yunnanensis responded to altitude differently from that of the treeline species. At the species level, total NSC was not consistently more abundant in treeline trees than in trees of the same species growing at lower elevations. Thus there was no consistent evidence for carbon limitation of growth in treeline trees. For the three treeline species studied (P. balfouriana and A. fabri in the Kang-Ding Valley and A. fabri in the Mo-Xi Valley), winter NSC concentrations in treeline trees were significantly lower than in lower-elevation trees of the same species, suggesting that, in winter, carbon is limited in treeline trees. However, in no case was there total overwinter depletion of NSC or its components in treeline trees. Treeline and low-altitude species had similar sugar:starch ratios of about three at their upper-elevational limits in April. We conclude that survival and growth of trees at the elevational or latitudinal climate limit depend not only on NSC concentration in perennial tissues, but also on the maintenance of an overwintering sugar:starch ratio greater than three.

  11. In situ formation of poly(vinyl alcohol–heparin hydrogels for mild encapsulation and prolonged release of basic fibroblast growth factor and vascular endothelial growth factor

    Directory of Open Access Journals (Sweden)

    Justine J Roberts

    2016-11-01

    Full Text Available Heparin-based hydrogels are attractive for controlled growth factor delivery, due to the native ability of heparin to bind and stabilize growth factors. Basic fibroblast growth factor and vascular endothelial growth factor are heparin-binding growth factors that synergistically enhance angiogenesis. Mild, in situ encapsulation of both basic fibroblast growth factor and vascular endothelial growth factor and subsequent bioactive dual release has not been demonstrated from heparin-crosslinked hydrogels, and the combined long-term delivery of both growth factors from biomaterials is still a major challenge. Both basic fibroblast growth factor and vascular endothelial growth factor were encapsulated in poly(vinyl alcohol-heparin hydrogels and demonstrated controlled release. A model cell line, BaF32, was used to show bioactivity of heparin and basic fibroblast growth factor released from the gels over multiple days. Released basic fibroblast growth factor promoted higher human umbilical vein endothelial cell outgrowth over 24 h and proliferation for 3 days than the poly(vinyl alcohol-heparin hydrogels alone. The release of vascular endothelial growth factor from poly(vinyl alcohol-heparin hydrogels promoted human umbilical vein endothelial cell outgrowth but not significant proliferation. Dual-growth factor release of basic fibroblast growth factor and vascular endothelial growth factor from poly(vinyl alcohol-heparin hydrogels resulted in a synergistic effect with significantly higher human umbilical vein endothelial cell outgrowth compared to basic fibroblast growth factor or vascular endothelial growth factor alone. Poly(vinyl alcohol-heparin hydrogels allowed bioactive growth factor encapsulation and provided controlled release of multiple growth factors which is beneficial toward tissue regeneration applications.

  12. The epidermal growth factor system in Caenorhabditis elegans.

    Science.gov (United States)

    Moghal, Nadeem; Sternberg, Paul W

    2003-03-10

    The single known epidermal growth factor-like growth factor and single epidermal growth factor receptor in Caenorhabditis elegans mediate two types of processes, each via a distinct signal transduction pathway. Several instances of cell fate specification during organogenesis require the RAS-MAP kinase pathway, as well as multiple nuclear factors. By contrast, appropriate myoepithelial contractions during ovulation involve IP3-mediated signal transduction. Positive modulators of the RAS pathway include KSR, SUR-8, phosphatase PP2A, and a zinc cation diffusion facilitator. Negative regulators of the RAS pathway include homologs of CBL, GAP-1, ACK, and MAP kinase phosphatase, while negative regulators of the IP3 pathway are enzymes that modify IP3. In addition to its stimulation of RAS activity, the GRB2 homolog SEM-5 acts negatively on both signaling pathways, as does the Ack-related kinase ARK-1.

  13. P01.02FIBROBLAST GROWTH FACTOR 4 CONTRIBUTES TO 3-DIMENSIONAL GROWTH OF HUMAN GLIOBLASTOMA

    OpenAIRE

    Lötsch, D.; Englinger, B.; Pichler, J; Hainfellner, J; Marosi, C; Czech, T.; Knosp, E.; Buchroithner, J; Spiegl-Kreinecker, S.; Berger, W

    2014-01-01

    Glioblastoma growth is driven by receptor tyrosine kinase (RTK)-mediated signals. One of the RTK systems recently coming into focus are the fibroblast growth factor (FGF) high-affinity receptors (FGFR1-FGFR4) due to mutation, overexpression or translocation in several cancer types. FGF/FGFR represents a complex signal network with essential functions in embryonic development, tissue homeostasis and wound healing but also for malignant transformation and growth as well as tumor neoangiogenesis...

  14. Soil texture and climatc conditions for biocrust growth limitation: a meta analysis

    Science.gov (United States)

    Fischer, Thomas; Subbotina, Mariia

    2015-04-01

    Along with afforestation, attempts have been made to combat desertification by managing soil crusts, and is has been reported that recovery rates of biocrusts are dependent on many factors, including the type, severity, and extent of disturbance; structure of the vascular plant community; conditions of adjoining substrates; availability of inoculation material; and climate during and after disturbance (Belnap & Eldridge 2001). Because biological soil crusts are known to be more stable on and to prefer fine substrates (Belnap 2001), the question arises as to how successful crust management practices can be applied to coarser soil. In previous studies we observed similar crust biomasses on finer soils under arid and on coarser soils under temperate conditions. We hypothesized that the higher water holding capacity of finer substrates would favor crust development, and that the amount of silt and clay in the substrate that is required for enhanced crust development would vary with changes in climatic conditions. In a global meta study, climatic and soil texture threshold values promoting BSC growth were derived. While examining literature sources, it became evident that the amount of studies to be incorporated into this meta analysis was reversely related to the amount of common environmental parameters they share. We selected annual mean precipitaion, mean temperature and the amount of silt and clay as driving variables for crust growth. Response variable was the "relative crust biomass", which was computed per literature source as the ratio between each individual crust biomass value of the given study to the study maximum value reported. We distinguished lichen, green algal, cyanobacterial and moss crusts. To quantify threshold conditions at which crust biomass responded to differences in texture and climate, we (I) determined correlations between bioclimatic variables, (II) calculated linear models to determine the effect of typical climatic variables with soil

  15. Insulin-like growth factor-I in growth and metabolism

    DEFF Research Database (Denmark)

    Backeljauw, P; Bang, P; Dunger, D B;

    2010-01-01

    Deficiency of insulin-like growth factor-I (IGF-I) results in growth failure. A variety of molecular defects have been found to underlie severe primary IGF-I deficiency (IGFD), in which serum IGF-I concentrations are substantially decreased and fail to respond to GH therapy. Identification of mor...

  16. Insulin-like growth factor-I in growth and metabolism

    DEFF Research Database (Denmark)

    Backeljauw, P; Bang, P; Dunger, D B

    2010-01-01

    Deficiency of insulin-like growth factor-I (IGF-I) results in growth failure. A variety of molecular defects have been found to underlie severe primary IGF-I deficiency (IGFD), in which serum IGF-I concentrations are substantially decreased and fail to respond to GH therapy. Identification of more...

  17. Distribution and number of epidermal growth factor receptors in skin is related to epithelial cell growth

    DEFF Research Database (Denmark)

    Green, M R; Basketter, D A; Couchman, J R

    1983-01-01

    Epidermal growth factor (EGF), a low-molecular-weight polypeptide (G. Carpenter and S. Cohen, 1979, Annu. Rev. Biochem. 48, 193-216), stimulates the proliferation and keratinisation of cultured embryonic epidermis (S. Cohen, 1965, Dev. Biol. 12, 394-407) and promotes epidermal growth, thickening,...

  18. Two-dimensional growth of germanium under a diffusion limited aggregation environment

    Science.gov (United States)

    Lee, Jaejun; Kim, Sung Wook; Park, Youn Ho; Park, Jeong Min; Kim, Yeon Joo; Park, Sangwon; Yang, Jeen Moon; Choi, Heon-Jin

    2017-01-01

    The discovery of graphene has triggered immense interest in two-dimensional (2D) nanomaterials. However, the 2D growth of several layerstructured crystals such as graphene, MoS2, and black phosphorus is difficult and limited. Here, we report the gas-phase 2D growth of germanium (Ge) with a cubic structure to form Ge nanosheets (GeNSs) using the chemical vapor deposition method. Our investigation revealed that a diffusion limited aggregation (DLA) environment is essential for the 2D growth of Ge that induces a dendritic growth in the direction and suppresses the growth in the [111] direction. The growth behavior was similar to the 2D growth of silicon reported previously. Thus, it can be concluded that a DLA environment is essential for the 2D growth of cubic structured materials. The electron density and mobility of GeNSs were found to be 1.3 × 1015 cm-3 and 792 cm2/Vs, respectively, and their resistivity varied with the intensity of light. [Figure not available: see fulltext.

  19. Transforming growth factor alpha controls the transition from hypertrophic cartilage to bone during endochondral bone growth.

    Science.gov (United States)

    Usmani, Shirine E; Pest, Michael A; Kim, Gunwoo; Ohora, Sara N; Qin, Ling; Beier, Frank

    2012-07-01

    We have recently identified transforming growth factor alpha (TGFα) as a novel growth factor involved in the joint disease osteoarthritis. The role of TGFα in normal cartilage and bone physiology however, has not been well defined. The objective of this study was to determine the role of TGFα in bone development through investigation of the Tgfa knockout mouse. The gross skeletons as well as the cartilage growth plates of Tgfa knockout mice and their control littermates were examined during several developmental stages ranging from newborn to ten weeks old. Knockout mice experienced skeletal growth retardation and expansion of the hypertrophic zone of the growth plate. These phenotypes were transient and spontaneously resolved by ten weeks of age. Tgfa knockout growth plates also had fewer osteoclasts along the cartilage/bone interface. Furthermore, knockout mice expressed less RUNX2, RANKL, and MMP13 mRNA in their cartilage growth plates than controls did. Tgfa knockout mice experience a delay in bone development, specifically the conversion of hypertrophic cartilage to true bone. The persistence of the hypertrophic zone of the growth plate appears to be mediated by a decrease in MMP13 and RANKL expression in hypertrophic chondrocytes and a resulting reduction in osteoclast recruitment. Overall, TGFα appears to be an important growth factor regulating the conversion of cartilage to bone during the process of endochondral ossification. Copyright © 2012 Elsevier Inc. All rights reserved.

  20. Advances in pubertal growth and factors influencing it: Can we increase pubertal growth?

    Directory of Open Access Journals (Sweden)

    Ashraf Soliman

    2014-01-01

    Full Text Available Puberty is a period of development characterized by partially concurrent changes which includes growth acceleration, alteration in body composition and appearance of secondary sex characteristics. Puberty is characterized by an acceleration and then deceleration in skeletal growth. The initiation, duration and amount of growth vary considerably during the growth spurt. Pubertal growth and biological maturation are dynamic processes regulated by a variety of genetic and environmental factors. Changes in skeletal maturation and bone mineral accretion concomitant with the stage of pubertal development constitute essential components in the evaluation of growth during this pubertal period. Genetic, endocrine and nutritional factors and ethnicity contribute variably to the amount of growth gained during this important period of rapid changes. Many studies investigated the possibility of increasing pubertal growth to gain taller final adult height in adolescents with idiopathic short stature (ISS. The pattern of pubertal growth, its relation to sex maturity rating and factors affecting them has been addressed in this review. The results of different trials to increase final adult height of adolescents using different hormones have been summarized. These data enables Endocrinologists to give in-depth explanations to patients and families about the efficacy and clinical significance as well as the safety of using these therapies in the treatment of adolescents with ISS.

  1. The strength of limiting factors for duckweed during algal competition

    NARCIS (Netherlands)

    Szabo, S.; Roijackers, R.M.M.; Scheffer, M.; Borics, G.

    2005-01-01

    Duckweed (Lemna gibba) growth was found to be strongly reduced by unicellular green algae (Scenedesmus conspicua, Chlorella sp., Chlamydomonas sp.) in indoor experiments. These algae reduced N, P, Fe and Mn concentrations of the medium drastically, moreover they increased the pH beyond 10.

  2. The strength of limiting factors for duckweed during algal competition

    NARCIS (Netherlands)

    Szabo, S.; Roijackers, R.M.M.; Scheffer, M.; Borics, G.

    2005-01-01

    Duckweed (Lemna gibba) growth was found to be strongly reduced by unicellular green algae (Scenedesmus conspicua, Chlorella sp., Chlamydomonas sp.) in indoor experiments. These algae reduced N, P, Fe and Mn concentrations of the medium drastically, moreover they increased the pH beyond 10. Subsequen

  3. The strength of limiting factors for duckweed during algal competition

    NARCIS (Netherlands)

    Szabo, S.; Roijackers, R.M.M.; Scheffer, M.; Borics, G.

    2005-01-01

    Duckweed (Lemna gibba) growth was found to be strongly reduced by unicellular green algae (Scenedesmus conspicua, Chlorella sp., Chlamydomonas sp.) in indoor experiments. These algae reduced N, P, Fe and Mn concentrations of the medium drastically, moreover they increased the pH beyond 10. Subsequen

  4. Making a tooth: growth factors, transcription factors, and stem cells

    Institute of Scientific and Technical Information of China (English)

    Yah Ding ZHANG; Zhi CHEN; Yi Qiang SONG; Chao LIU; Yi Ping CHEN

    2005-01-01

    Mammalian tooth development is largely dependent on sequential and reciprocal epithelial-mesenchymal interactions.These processes involve a series of inductive and permissive interactions that result in the determination, differentiation,and organization of odontogenic tissues. Multiple signaling molecules, including BMPs, FGFs, Shh, and Wnt proteins,have been implicated in mediating these tissue interactions. Transcription factors participate in epithelial-mesenchymal interactions via linking the signaling loops between tissue layers by responding to inductive signals and regulating the expression of other signaling molecules. Adult stem cells are highly plastic and multipotent. These cells including dental pulp stem cells and bone marrow stromal cells could be reprogrammed into odontogenic fate and participated in tooth formation. Recent progress in the studies of molecular basis of tooth development, adult stem cell biology, and regeneration will provide fundamental knowledge for the realization of human tooth regeneration in the near future.

  5. Growth limits on bank assets: regional effects and the structure of the banking system.

    Directory of Open Access Journals (Sweden)

    A. NICCOLI

    2013-12-01

    Full Text Available In recent years, Italian monetary policy has become increasingly based on administrative controls. Among theses, the most important are the limits of growth and constraints of the portfolio composition. The former impose a maximum growth rate of total loans in lire on banks, while the latter obliges them to invest a given amount of the increases in deposits in securities with specific characteristics. The present article examines a side effect of growth limits, namely their effect from a geographical point of view and on the structure of the Italian banking system. In particular, the author shows that the occurrence of growth ceilings for a given bank is greater the more rapid the increase in its deposits and the smaller the geographical area in which it operates.

  6. Consideration of Zener drag effect by introducing a limiting radius for neighbourhood in grain growth simulation

    Science.gov (United States)

    Maazi, N.; Rouag, N.

    2002-08-01

    A model for grain growth simulation, in the presence of preferential particle distribution, is presented. The model predicts two grain size limits due to second-phase particles. Less than the maximal critical radius the grains will shrink. Greater than the minimal critical radius the grains will grow. Between the two limiting radii no grain growth takes place. These critical radii permit us to introduce the effect of the precipitates directly in the simulation procedure, without their assigning sites in the base matrix. In this case, all sites of the matrix are only occupied by grains. The conditions necessary for the development of secondary recrystallization in textured materials such as Fe-3%Si are, first, the stagnation of normal grain growth, second, the presence of special boundaries around the secondary grains. The grain growth simulation is performed until the grain structure was pinned, i.e. when boundaries become pinned.

  7. Beclin 1 regulates growth factor receptor signaling in breast cancer.

    Science.gov (United States)

    Rohatgi, R A; Janusis, J; Leonard, D; Bellvé, K D; Fogarty, K E; Baehrecke, E H; Corvera, S; Shaw, L M

    2015-10-16

    Beclin 1 is a haploinsufficient tumor suppressor that is decreased in many human tumors. The function of beclin 1 in cancer has been attributed primarily to its role in the degradative process of macroautophagy. However, beclin 1 is a core component of the vacuolar protein sorting 34 (Vps34)/class III phosphatidylinositoI-3 kinase (PI3KC3) and Vps15/p150 complex that regulates multiple membrane-trafficking events. In the current study, we describe an alternative mechanism of action for beclin 1 in breast cancer involving its control of growth factor receptor signaling. We identify a specific stage of early endosome maturation that is regulated by beclin 1, the transition of APPL1-containing phosphatidyIinositol 3-phosphate-negative (PI3P(-)) endosomes to PI3P(+) endosomes. Beclin 1 regulates PI3P production in response to growth factor stimulation to control the residency time of growth factor receptors in the PI3P(-)/APPL(+)-signaling-competent compartment. As a result, suppression of BECN1 sustains growth factor-stimulated AKT and ERK activation resulting in increased breast carcinoma cell invasion. In human breast tumors, beclin 1 expression is inversely correlated with AKT and ERK phosphorylation. Our data identify a novel role for beclin 1 in regulating growth factor signaling and reveal a mechanism by which loss of beclin 1 expression would enhance breast cancer progression.

  8. Growth of Geobacter sulfurreducens under nutrient-limiting conditions in continuous culture.

    Science.gov (United States)

    Esteve-Núñez, Abraham; Rothermich, Mary; Sharma, Manju; Lovley, Derek

    2005-05-01

    A system for growing Geobacter sulfurreducens under anaerobic conditions in chemostats was developed in order to study the physiology of this organism under conditions that might more closely approximate those found in the subsurface than batch cultures. Geobacter sulfurreducens could be cultured under acetate-limiting conditions with fumarate or Fe(III)-citrate as the electron acceptor at growth rates between 0.04 and 0.09 h(-1). The molar growth yield was threefold higher with fumarate as the electron acceptor than with Fe(III), despite the lower mid-point potential of the fumarate/succinate redox couple. When growth was limited by availability of fumarate, high steady-state concentrations were detected, suggesting that fumarate is unlikely to be an important electron acceptor in sedimentary environments. The half-saturation constant, Ks, for acetate in Fe(III)-grown cultures (10 microM) suggested that the growth of Geobacter species is likely to be acetate limited in most subsurface sediments, but that when millimolar quantities of acetate are added to the subsurface in order to promote the growth of Geobacter for bioremediation applications, this should be enough to overcome any acetate limitations. When the availability of electron acceptors, rather than acetate, limited growth, G. sulfurreducens was less efficient in incorporating acetate into biomass but had higher respiration rates, a desirable physiological characteristic when adding acetate to stimulate the activity of Geobacter species during in situ uranium bioremediation. These results demonstrate that the ability to study the growth of G. sulfurreducens under steady-state conditions can provide insights into its physiological characteristics that have relevance for its activity in a diversity of sedimentary environments.

  9. Stationary Growth and Unique Invariant Harmonic Measure of Cylindrical Diffusion Limited Aggregation

    Science.gov (United States)

    Marchetti, Riccardo; Taloni, Alessandro; Caglioti, Emanuele; Loreto, Vittorio; Pietronero, Luciano

    2012-08-01

    We prove that the harmonic measure is stationary, unique, and invariant on the interface of diffusion limited aggregation (DLA) growing on a cylinder surface. We provide a detailed theoretical analysis puzzling together multiscaling, multifractality, and conformal invariance, supported by extensive numerical simulations of clusters built using conformal mappings and on a lattice. The growth properties of the active and frozen zones are clearly elucidated. We show that the unique scaling exponent characterizing the stationary growth is the DLA fractal dimension.

  10. Existence of limit cycles in the Solow model with delayed-logistic population growth.

    Science.gov (United States)

    Bianca, Carlo; Guerrini, Luca

    2014-01-01

    This paper is devoted to the existence and stability analysis of limit cycles in a delayed mathematical model for the economy growth. Specifically the Solow model is further improved by inserting the time delay into the logistic population growth rate. Moreover, by choosing the time delay as a bifurcation parameter, we prove that the system loses its stability and a Hopf bifurcation occurs when time delay passes through critical values. Finally, numerical simulations are carried out for supporting the analytical results.

  11. Property value assessment growth limits, tax base erosion and regional in-migration

    OpenAIRE

    Skidmore, Mark; Tosun, Mehmet Serkan

    2010-01-01

    In 1994 a limit on the growth of property values for tax purposes was imposed in Michigan. One consequence of the newly imposed assessment growth cap was an emerging differential in tax prices between potential new property owners and long-time property owners. The purpose of this paper is to examine the impact of this growing tax price differential on migration patterns. Using county level data on migration activity over the 1994-2006 period, we present evidence that differential tax prices ...

  12. Engineering a growth factor embedded nanofiber matrix niche to promote vascularization for functional cardiac regeneration.

    Science.gov (United States)

    Lakshmanan, Rajesh; Kumaraswamy, Priyadharshini; Krishnan, Uma Maheswari; Sethuraman, Swaminathan

    2016-08-01

    The major loss of tissue extracellular matrix (ECM) after myocardial ischemia is a serious burden that gradually leads to heart failure. Due to lack of available treatment methods to restore the cardiac function, various research strategies have come up to treat the ischemic myocardium. However these have met with limited success due to the complexity of the cardiac tissue, which exhibits a nanofibrous collagenous matrix with spatio-temporal localization of a combination of growth factors. To mimic the topographical and chemical cues of the natural cardiac tissue, we have fabricated a growth factor embedded nanofibrous scaffold through electrospinning. In our previous work, we have reported a nanofibrous matrix made of PLCL and PEOz with an average diameter of 500 nm. The scaffold properties were specifically characterized in vitro for cardio-compatibility. In the present study, we have loaded dual growth factors VEGF and bFGF in the nanofiber matrix and investigated its suitability for cardiac tissue engineering. The encapsulation and release of dual growth factors from the matrix were studied using XPS and ELISA. Bioactivity of the loaded growth factors towards proliferation and migration of endothelial cells (HUVECs) was evaluated through MTS and Boyden chamber assays respectively. The efficiency of growth factors on the nanofibrous matrix to activate signaling molecules was studied in HUVECs through gene expression analysis. Preclinical evaluation of the growth factor embedded nanofibrous patch in a rabbit acute myocardial infarction (AMI) model was studied and cardiac function assessment was made through ECG and echocardiography. The evidence for angiogenesis in the patch secured regions was analyzed through histopathology and immunohistochemistry. Our results confirm the effectiveness of growth factor embedded nanofiber matrix in restoration of cardiac function after ischemia when compared to conventional patch material thereby exhibiting promise as a

  13. The use of food imports to overcome local limits to growth

    Science.gov (United States)

    Porkka, Miina; Guillaume, Joseph H. A.; Siebert, Stefan; Schaphoff, Sibyll; Kummu, Matti

    2017-04-01

    There is a fundamental tension between population growth and carrying capacity, i.e., the population that could potentially be supported using the resources and technologies available at a given time. When population growth outpaces improvements in food production locally, food imports can avoid local limits and allow growth to continue. This import strategy is central to the debate on food security with continuing rapid growth of the world population. This highlights the importance of a quantitative global understanding of where the strategy is implemented, whether it has been successful, and what drivers are involved. We present an integrated quantitative analysis to answer these questions at sub-national and national scale for 1961-2009, focusing on water as the key limiting resource and accounting for resource and technology impacts on local carrying capacity. According to the sub-national estimates, food imports have nearly universally been used to overcome local limits to growth, affecting 3.0 billion people—81% of the population that is approaching or already exceeded local carrying capacity. This strategy is successful in 88% of the cases, being highly dependent on economic purchasing power. In the unsuccessful cases, increases in imports and local productivity have not kept pace with population growth, leaving 460 million people with insufficient food. Where the strategy has been successful, food security of 1.4 billion people has become dependent on imports. Whether or not this dependence on imports is considered desirable, it has policy implications that need to be taken into account.

  14. Nanoparticle growth by collection of ions: orbital motion limited theory and collision-enhanced collection

    Science.gov (United States)

    Pilch, I.; Caillault, L.; Minea, T.; Helmersson, U.; Tal, A. A.; Abrikosov, I. A.; Münger, E. P.; Brenning, N.

    2016-10-01

    The growth of nanoparticles in plasma is modeled for situations where the growth is mainly due to the collection of ions of the growth material. The model is based on the classical orbit motion limited (OML) theory with the addition of a collision-enhanced collection (CEC) of ions. The limits for this type of model are assessed with respect to three processes that are not included: evaporation of the growth material, electron field emission, and thermionic emission of electrons. It is found that both evaporation and thermionic emission can be disregarded below a temperature that depends on the nanoparticle material and on the plasma parameters; for copper in our high-density plasma this limit is about 1200 K. Electron field emission can be disregarded above a critical nanoparticle radius, in our case around 1.4 nm. The model is benchmarked, with good agreement, to the growth of copper nanoparticles from a radius of 5 nm-20 nm in a pulsed power hollow cathode discharge. Ion collection by collisions contributes with approximately 10% of the total current to particle growth, in spite of the fact that the collision mean free path is four orders of magnitude longer than the nanoparticle radius.

  15. Inclined defects and their effect on the fatigue limit and small crack growth

    Directory of Open Access Journals (Sweden)

    Roiko Andrew

    2014-06-01

    Full Text Available Small FIB (Focused Ion Beam milled notches were introduced in quenched and tempered 34CrNiMo6 steel to monitor initiation and growth of cracks in situ. The effect of the defects on the fatigue limit is discussed in terms of the √area model. Notches with projected √area of 30 to 56 μm normal to the applied stress were inclined by 0, 45, and 60 degrees. The effect of size and inclination on the small crack growth as well as the fatigue limit is discussed.

  16. Transforming growth factor-beta1 induces transforming growth factor-beta1 and transforming growth factor-beta receptor messenger RNAs and reduces complement C1qB messenger RNA in rat brain microglia.

    Science.gov (United States)

    Morgan, T E; Rozovsky, I; Sarkar, D K; Young-Chan, C S; Nichols, N R; Laping, N J; Finch, C E

    2000-01-01

    Transforming growth factor-beta1 is a multifunctional peptide with increased expression during Alzheimer's disease and other neurodegenerative conditions which involve inflammatory mechanisms. We examined the autoregulation of transforming growth factor-beta1 and transforming growth factor-beta receptors and the effects of transforming growth factor-beta1 on complement C1q in brains of adult Fischer 344 male rats and in primary glial cultures. Perforant path transection by entorhinal cortex lesioning was used as a model for the hippocampal deafferentation of Alzheimer's disease. In the hippocampus ipsilateral to the lesion, transforming growth factor-beta1 peptide was increased >100-fold; the messenger RNAs encoding transforming growth factor-beta1, transforming growth factor-beta type I and type II receptors were also increased, but to a smaller degree. In this acute lesion paradigm, microglia are the main cell type containing transforming growth factor-beta1, transforming growth factor-beta type I and II receptor messenger RNAs, shown by immunocytochemistry in combination with in situ hybridization. Autoregulation of the transforming growth factor-beta1 system was examined by intraventricular infusion of transforming growth factor-beta1 peptide, which increased hippocampal transforming growth factor-beta1 messenger RNA levels in a dose-dependent fashion. Similarly, transforming growth factor-beta1 increased levels of transforming growth factor-beta1 messenger RNA and transforming growth factor-beta type II receptor messenger RNA (IC(50), 5pM) and increased release of transforming growth factor-beta1 peptide from primary microglia cultures. Interactions of transforming growth factor-beta1 with complement system gene expression are also indicated, because transforming growth factor-beta1 decreased C1qB messenger RNA in the cortex and hippocampus, after intraventricular infusion, and in cultured glia. These indications of autocrine regulation of transforming growth

  17. A third option for climate policy within potential limits to growth

    Science.gov (United States)

    van den Bergh, Jeroen C. J. M.

    2017-02-01

    Climate change has revived debates around the concept of limits to growth, 45 years after it was first proposed. Many citizens, scientists and politicians fear that stringent climate policy will harm economic growth. Some are anti-growth, whereas others believe green growth is compatible with a transition to a low-carbon economy. As the window to curb warming at 2 °C closes, this debate will intensify. This Review critically reflects on both positions, providing an overview of existing literature on the growth versus climate debate. Both positions are argued here to jeopardize environmental or social goals. A third position, labelled an 'agrowth' strategy, is proposed to depolarize the debate and reduce resistance to climate policies.

  18. Limiter

    Science.gov (United States)

    Cohen, S.A.; Hosea, J.C.; Timberlake, J.R.

    1984-10-19

    A limiter with a specially contoured front face is provided. The front face of the limiter (the plasma-side face) is flat with a central indentation. In addition, the limiter shape is cylindrically symmetric so that the limiter can be rotated for greater heat distribution. This limiter shape accommodates the various power scrape-off distances lambda p, which depend on the parallel velocity, V/sub parallel/, of the impacting particles.

  19. Enhanced Phosphoproteomic Profiling Workflow For Growth Factor Signaling Analysis

    DEFF Research Database (Denmark)

    Sylvester, Marc; Burbridge, Mike; Leclerc, Gregory;

    2010-01-01

    Background Our understanding of complex signaling networks is still fragmentary. Isolated processes have been studied extensively but cross-talk is omnipresent and precludes intuitive predictions of signaling outcomes. The need for quantitative data on dynamic systems is apparent especially for our...... A549 lung carcinoma cells were used as a model and stimulated with hepatocyte growth factor, epidermal growth factor or fibroblast growth factor. We employed a quick protein digestion workflow with spin filters without using urea. Phosphopeptides in general were enriched by sequential elution from...... transfer dissociation adds confidence in modification site assignment. The workflow is relatively simple but the integration of complementary techniques leads to a deeper insight into cellular signaling networks and the potential pharmacological intervention thereof....

  20. Effects of Growth Factors on Dental Stem/ProgenitorCells

    Science.gov (United States)

    Kim, Sahng G.; Solomon, Charles; Zheng, Ying; Suzuki, Takahiro; Mo, Chen; Song, Songhee; Jiang, Nan; Cho, Shoko; Zhou, Jian; Mao, Jeremy J.

    2014-01-01

    Synopsis The primary goal of regenerative endodontics is to restore the vitality and functions of the dentin-pulp complex, as opposed to filing of the root canal with bioinert materials. Structural restoration is also important but is likely secondary to vitality and functions. Myriads growth factors regulate multiple cellular functions including migration, proliferation, differentiation and apoptosis of several cell types that are intimately involved in dentin-pulp regeneration: odontoblasts, interstitial fibroblasts, vascular-endothelial cells and sprouting nerve fibers. Recent work showing that growth factor delivery, without cell transplantation, can yield pulp-dentin like tissues in vivo provides one of the tangible pathways for regenerative endodontics. This review synthesizes our knowledge on a multitude of growth factors that are known or anticipated to be efficacious in dental pulp-dentin regeneration. PMID:22835538

  1. ANALYSIS OF FACTORS WHICH AFFECTING THE ECONOMIC GROWTH

    Directory of Open Access Journals (Sweden)

    Suparna Wijaya

    2017-03-01

    Full Text Available High economic growth and sustainable process are main conditions for sustainability of economic country development. They are also become measures of the success of the country's economy. Factors which tested in this study are economic and non-economic factors which impacting economic development. This study has a goal to explain the factors that influence on macroeconomic Indonesia. It used linear regression modeling approach. The analysis result showed that Tax Amnesty, Exchange Rate, Inflation, and interest rate, they jointly can bring effect which amounted to 77.6% on economic growth whereas the remaining 22.4% is the influenced by other variables which not observed in this study. Keywords: tax amnesty, exchange rates, inflation, SBI and economic growth

  2. Insulin-like growth factors act synergistically with basic fibroblast growth factor and nerve growth factor to promote chromaffin cell proliferation

    DEFF Research Database (Denmark)

    Frödin, M; Gammeltoft, S

    1994-01-01

    We have investigated the effects of insulin-like growth factors (IGFs), basic fibroblast growth factor (bFGF), and nerve growth factor (NGF) on DNA synthesis in cultured chromaffin cells from fetal, neonatal, and adult rats by using 5-bromo-2'-deoxyuridine (BrdUrd) pulse labeling for 24 or 48 h......% of fetal, 20% of neonatal, and 2% of adult chromaffin cells. The ED50 value of IGF-I- and IGF-II-stimulated BrdUrd labeling in neonatal chromaffin cells was 0.3 nM and 0.8 nM, respectively. In neonatal and adult chromaffin cells, addition of 1 nM bFGF or 2 nM NGF stimulated nuclear BrdUrd incorporation...... to approximately the same level as 10 nM IGF-I or IGF-II. However, the response to bFGF or NGF in combination with either IGF-I or IGF-II was more than additive, indicating that the combined effect of the IGFs and bFGF or NGF is synergistic. The degree of synergism was 2- to 4-fold in neonatal chromaffin cells...

  3. Heparin Binding Epidermal Growth Factor-Like Growth Factor Heals Chronic Tympanic Membrane Perforations With Advantage Over Fibroblast Growth Factor 2 and Epidermal Growth Factor in an Animal Model.

    Science.gov (United States)

    Santa Maria, Peter Luke; Weierich, Kendall; Kim, Sungwoo; Yang, Yunzhi Peter

    2015-08-01

    That heparin binding epidermal growth factor-like growth factor (HB-EGF) heals chronic tympanic membrane (TM) perforations at higher rates than fibroblast growth factor 2 (FGF2) and epidermal growth factor (EGF) in an animal model. A nonsurgical treatment for chronic TM perforation would benefit those unable to access surgery or those unable to have surgery, as well as reducing the cost of tympanoplasty. Growth factor (GF) treatments have been reported in the literature with variable success with the lack of a suitable animal providing a major obstacle. The GFs were tested in a validated mouse model of chronic TM perforation. A bioabsorbable hydrogel polymer was used to deliver the GF at a steady concentration as it dissolved over 4 weeks. A control (polymer only, n = 18) was compared to polymer loaded with HB-EGF (5 μg/ml, n = 18), FGF2 (100 μg/ml, n = 19), and EGF (250 μg/ml, n = 19). Perforations were inspected at 4 weeks. The healing rates, as defined as 100% perforation closure, were control (5/18, 27.8%), HB-EGF (15/18, 83.3%), FGF2 (6/19, 31.6%), and EGF (3/19, 15.8%). There were no differences between FGF2 (p = 0.80) and EGF (p = 0.31) with control healing rates. HB-EGF (p = 0.000001) showed a significant difference for healing. The HB-EGF healed TMs showed layers similar to a normal TM, whereas the other groups showed a lack of epithelial migration. This study confirms the advantage of HB-EGF over two other commonly used growth factors and is a promising nonsurgical treatment of chronic TM perforations.

  4. Limiting factors of exercise performance 1 year after lung transplantation

    NARCIS (Netherlands)

    Reinsma, G. D.; ten Hacken, N. H. T.; Grevink, R. G.; van der Bij, W.; Koer, G. H.; van Weert, E.

    2006-01-01

    Background: After lung transplantation (LTx). exercise capacity frequently remains limited, despite significantly improved pulmonary function. The aim of this study was to evaluate maximal exercise capacity and peripheral muscle force before and 1 year after LTx, and to determine whether peripheral

  5. The Singular Limit of a Chemotaxis-Growth System with General Initial Data

    CERN Document Server

    Alfaro, Matthieu

    2009-01-01

    We study the singular limit of a system of partial differential equations which is a model for an aggregation of amoebae subjected to three effects: diffusion, growth and chemotaxis. The limit problem involves motion by mean curvature together with a nonlocal drift term. We consider rather general initial data. We prove a generation of interface property and study the motion of interfaces. We also obtain an optimal estimate of the thickness and the location of the transition layer that develops.

  6. The effects of defoliation on carbon allocation: can carbon limitation reduce growth in favour of storage?

    Science.gov (United States)

    Wiley, Erin; Huepenbecker, Sarah; Casper, Brenda B; Helliker, Brent R

    2013-11-01

    There is no consensus about how stresses such as low water availability and temperature limit tree growth. Sink limitation to growth and survival is often inferred if a given stress does not cause non-structural carbohydrate (NSC) concentrations or levels to decline along with growth. However, trees may actively maintain or increase NSC levels under moderate carbon stress, making the pattern of reduced growth and increased NSCs compatible with carbon limitation. To test this possibility, we used full and half defoliation to impose severe and moderate carbon limitation on 2-year-old Quercus velutina Lam. saplings grown in a common garden. Saplings were harvested at either 3 weeks or 4 months after treatments were applied, representing short- and longer-term effects on woody growth and NSC levels. Both defoliation treatments maintained a lower total leaf area than controls throughout the experiment with no evidence of photosynthetic up-regulation, and resulted in a similar total biomass reduction. While fully defoliated saplings had lower starch levels than controls in the short term, half defoliated saplings maintained control starch levels in both the short and longer term. In the longer term, fully defoliated saplings had the greatest starch concentration increment, allowing them to recover to near-control starch levels. Furthermore, between the two harvest dates, fully and half defoliated saplings allocated a greater proportion of new biomass to starch than did controls. The maintenance of control starch levels in half defoliated saplings indicates that these trees actively store a substantial amount of carbon before growth is carbon saturated. In addition, the allocation shift favouring storage in defoliated saplings is consistent with the hypothesis that, as an adaptation to increasing carbon stress, trees can prioritize carbon reserve formation at the expense of growth. Our results suggest that as carbon limitation increases, reduced growth is not necessarily

  7. Emerging Roles of Transforming Growth Factor β Signaling in Diabetic Retinopathy.

    Science.gov (United States)

    Wheeler, Sarah E; Lee, Nam Y

    2017-03-01

    Diabetic retinopathy (DR) is a serious complication of diabetes mellitus affecting about one third of diabetic adults. Despite its prevalence, treatment options are limited and often implemented only in the later stages of the disease. To date, the pathogenesis of DR has been extensively characterized in the context of elevated glucose, insulin, and VEGF signaling, although a growing number of other growth factors and molecules, including transforming growth factor β (TGF-β) are being recognized as important contributors and/or therapeutic targets. Here, we review the complex roles of TGF-β signaling in DR pathogenesis and progression. J. Cell. Physiol. 232: 486-489, 2017. © 2016 Wiley Periodicals, Inc.

  8. Constructing a blood vessel on the porous scaffold modified with vascular endothelial growth factor and basic fibroblast growth factor

    Science.gov (United States)

    Sevostyanova, V. V.; Matveeva, V. G.; Antonova, L. V.; Velikanova, E. A.; Shabaev, A. R.; Senokosova, E. A.; Krivkina, E. O.; Vasyukov, G. Yu.; Glushkova, T. V.; Kudryavtseva, Yu. A.; Barbarash, O. L.; Barbarash, L. S.

    2016-11-01

    Incorporation of the growth factors into biodegradable polymers is a promising approach for the fabrication of tissue-engineered vascular grafts. Here we blended poly(ɛ-caprolactone) (PCL) with poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) following incorporation of either vascular endothelial growth factor (VEGF) or basic fibroblast growth factor (bFGF) and then fabricated electrospun 2 mm diameter vascular grafts. Grafts without the growth factors were used as a control group. Structure of the grafts was assessed utilizing scanning electron microscopy. We further implanted our grafts into rat abdominal aorta for 1 and 3 months with the aim to test endothelialization, cell infiltration, and patency in vivo. Histological and immunofluorescence examination demonstrated enhanced endothelialization and cell infiltration of the grafts with either VEGF or bFGF compared to those without the growth factors. Grafts with VEGF showed higher patency compared to those with bFGF; however, bFGF promoted migration of smooth muscle cells and fibroblasts into the graft. Therefore, we conclude that incorporation of VEGF and bFGF into the inner and medial/outer layer, respectively, can be a promising option for the fabrication of tissue-engineered vascular grafts.

  9. Hybrid Thin Film Organosilica Sol-Gel Coatings To Support Neuronal Growth and Limit Astrocyte Growth.

    Science.gov (United States)

    Capeletti, Larissa Brentano; Cardoso, Mateus Borba; Dos Santos, João Henrique Zimnoch; He, Wei

    2016-10-07

    Thin films of silica prepared by a sol-gel process are becoming a feasible coating option for surface modification of implantable neural sensors without imposing adverse effects on the devices' electrical properties. In order to advance the application of such silica-based coatings in the context of neural interfacing, the characteristics of silica sol-gel are further tailored to gain active control of interactions between cells and the coating materials. By incorporating various readily available organotrialkoxysilanes carrying distinct organic functional groups during the sol-gel process, a library of hybrid organosilica coatings is developed and investigated. In vitro neural cultures using PC12 cells and primary cortical neurons both reveal that, among these different types of hybrid organosilica, the introduction of aminopropyl groups drastically transforms the silica into robust neural permissive substrate, supporting neuron adhesion and neurite outgrowth. Moreover, when this organosilica is cultured with astrocytes, a key type of glial cells responsible for glial scar response toward neural implants, such cell growth promoting effect is not observed. These findings highlight the potential of organo-group-bearing silica sol-gel to function as advanced coating materials to selectively modulate cell response and promote neural integration with implantable sensing devices.

  10. Placental Growth Factor Administration Abolishes Placental Ischemia-Induced Hypertension.

    Science.gov (United States)

    Spradley, Frank T; Tan, Adelene Y; Joo, Woo S; Daniels, Garrett; Kussie, Paul; Karumanchi, S Ananth; Granger, Joey P

    2016-04-01

    Preeclampsia is a pregnancy-specific disorder of new-onset hypertension. Unfortunately, the most effective treatment is early delivery of the fetus and placenta. Placental ischemia appears central to the pathogenesis of preeclampsia because placental ischemia/hypoxia induced in animals by reduced uterine perfusion pressure (RUPP) or in humans stimulates release of hypertensive placental factors into the maternal circulation. The anti-angiogenic factor soluble fms-like tyrosine kinase-1 (sFlt-1), which antagonizes and reduces bioavailable vascular endothelial growth factor and placental growth factor (PlGF), is elevated in RUPP rats and preeclampsia. Although PlGF and vascular endothelial growth factor are both natural ligands for sFlt-1, vascular endothelial growth factor also has high affinity to VEGFR2 (Flk-1) causing side effects like edema. PlGF is specific for sFlt-1. We tested the hypothesis that PlGF treatment reduces placental ischemia-induced hypertension by antagonizing sFlt-1 without adverse consequences to the mother or fetus. On gestational day 14, rats were randomized to 4 groups: normal pregnant or RUPP±infusion of recombinant human PlGF (180 μg/kg per day; AG31, a purified, recombinant human form of PlGF) for 5 days via intraperitoneal osmotic minipumps. On day 19, mean arterial blood pressure and plasma sFlt-1 were higher and glomerular filtration rate lower in RUPP than normal pregnant rats. Infusion of recombinant human PlGF abolished these changes seen with RUPP along with reducing oxidative stress. These data indicate that the increased sFlt-1 and reduced PlGF resulting from placental ischemia contribute to maternal hypertension. Our novel finding that recombinant human PlGF abolishes placental ischemia-induced hypertension, without major adverse consequences, suggests a strong therapeutic potential for this growth factor in preeclampsia.

  11. Cytokines and growth factors which regulate bone cell function

    Science.gov (United States)

    Seino, Yoshiki

    Everybody knows that growth factors are most important in making bone. Hormones enhance bone formation from a long distance. Growth factors promote bone formation as an autocrine or paracrine factor in nearby bone. BMP-2 through BMP-8 are in the TGF-β family. BMP makes bone by enchondral ossification. In bone, IGF-II is most abundant, second, TGF-β, and third IGF-I. TGF-β enhances bone formation mainly by intramembranous ossification in vivo. TGF-β affects both cell proliferation and differentiation, however, TGF-β mainly enhances bone formation by intramembranous ossification. Interestingly, TGF-β is increased by estrogen(E 2), androgen, vitamin D, TGF-β and FGF. IGF-I and IGF-II also enhance bone formation. At present it remains unclear why IGF-I is more active in bone formation than IGF-II, although IGF-II is more abundant in bone compared to IGF-I. However, if only type I receptor signal transduction promotes bone formation, the strong activity of IGF-I in bone formation is understandable. GH, PTH and E 2 promotes IGF-I production. Recent data suggest that hormones containing vitamin D or E 2 enhance bone formation through growth factors. Therefore, growth factors are the key to clarifying the mechanism of bone formation.

  12. Temperature affects insulin-like growth factor I and growth of juvenile southern flounder, Paralichthys lethostigma.

    Science.gov (United States)

    Luckenbach, J Adam; Murashige, Ryan; Daniels, Harry V; Godwin, John; Borski, Russell J

    2007-01-01

    Temperature profoundly influences growth of heterothermic vertebrates. However, few studies have investigated the effects of temperature on growth and insulin-like growth factor I (IGF-I) in fishes. The aim of this study was to examine effects of temperature on growth and establish whether IGF-I may mediate growth at different temperatures in southern flounder, Paralichthys lethostigma. In two experiments, juvenile flounder were reared at 23 and 28 degrees C and growth was monitored for either 117 or 197 days. Growth was similar across treatments in both experiments until fish reached approximately 100 mm total length. Body size then diverged with fish at 23 degrees C ultimately growing 65-83% larger than those at 28 degrees C. Muscle IGF-I mRNA, plasma IGF-I, and hepatosomatic index (HSI) were significantly higher in flounder at 23 degrees C, whereas hepatic IGF-I mRNA abundance did not differ with treatment. Muscle IGF-I mRNA was correlated with HSI, while plasma IGF-I was correlated with body size, hepatic IGF-I mRNA, and HSI. These results demonstrate a strong effect of temperature on flounder growth and show that temperature-induced variation in growth is associated with differences in systemic IGF-I and local (i.e., muscle) IGF-I mRNA levels. The results also support the use of plasma IGF-I and HSI as indicators of flounder growth status.

  13. Cheiradone: a vascular endothelial cell growth factor receptor antagonist

    Directory of Open Access Journals (Sweden)

    Ahmed Nessar

    2008-01-01

    Full Text Available Abstract Background Angiogenesis, the growth of new blood vessels from the pre-existing vasculature is associated with physiological (for example wound healing and pathological conditions (tumour development. Vascular endothelial growth factor (VEGF, fibroblast growth factor-2 (FGF-2 and epidermal growth factor (EGF are the major angiogenic regulators. We have identified a natural product (cheiradone isolated from a Euphorbia species which inhibited in vivo and in vitro VEGF- stimulated angiogenesis but had no effect on FGF-2 or EGF activity. Two primary cultures, bovine aortic and human dermal endothelial cells were used in in vitro (proliferation, wound healing, invasion in Matrigel and tube formation and in vivo (the chick chorioallantoic membrane models of angiogenesis in the presence of growth factors and cheiradone. In all cases, the concentration of cheiradone which caused 50% inhibition (IC50 was determined. The effect of cheiradone on the binding of growth factors to their receptors was also investigated. Results Cheiradone inhibited all stages of VEGF-induced angiogenesis with IC50 values in the range 5.20–7.50 μM but did not inhibit FGF-2 or EGF-induced angiogenesis. It also inhibited VEGF binding to VEGF receptor-1 and 2 with IC50 values of 2.9 and 0.61 μM respectively. Conclusion Cheiradone inhibited VEGF-induced angiogenesis by binding to VEGF receptors -1 and -2 and may be a useful investigative tool to study the specific contribution of VEGF to angiogenesis and may have therapeutic potential.

  14. Elevated CO2 and Phosphate Limitation Favor Micromonas pusilla through Stimulated Growth and Reduced Viral Impact

    NARCIS (Netherlands)

    Maat, Douwe S.; Crawfurd, Katherine J.; Timmermans, Klaas R.; Brussaard, Corina P. D.

    2014-01-01

    Growth and viral infection of the marine picoeukaryote Micromonas pusilla was studied under a future-ocean scenario of elevated partial CO2 (pCO(2); 750 mu atm versus the present-day 370 mu atm) and simultaneous limitation of phosphorus (P). Independent of the pCO(2) level, the ratios of M. pusilla

  15. Understanding growth limitation in wheat and sunflower under low phosphorus conditions.

    NARCIS (Netherlands)

    Rodriguez, D.

    1998-01-01

    The study described in this thesis focuses on the understanding of growth of leaf area and biomass in wheat and sunflower under low phosphorus conditions.Chapters 2 and 3 address the question whether P-deficiency limits leaf area expansion directly by inhibiting the individual leaf expansion, or thr

  16. Cow placenta extract promotes murine hair growth through enhancing the insulin - like growth factor-1

    Directory of Open Access Journals (Sweden)

    Dongliang Zhang

    2011-01-01

    Full Text Available Background: Hair loss is seen as an irreversible process. Most research concentrates on how to elongate the anagen, reduce the negative factors of obstructing hair growth and improve the hair number and size. Aim: In our experiment, we tried to prove that the cow placenta extract can promote hair growth by elongating hair shaft and increasing hair follicle number. Materials and Methods: Cow placenta extract (CPE, water and minoxidil applied separately on the back of depilated B57CL/6 mice for the case, negative and positive control respectively. We checked the proliferation of cells which are resident in hair sheath, and the expression of a few growth factors which stimulate hair growth. Results: Result shows that placenta extract more efficiently accelerates cell division and growth factor expression, by raising the insulin-like growth factor (IGF-1 mRNA and protein level to increase HF size and hair length. Conclusions: The extract is not a purified product; so, it is less effective than minoxidil, which is approved by the US FDA for the treatment of male pattern baldness. If refinement is done, the placenta extract would be a good candidate medicine for hair loss.

  17. Growth hormone and insulin-like growth factor-I as anabolic agents.

    Science.gov (United States)

    Welle, S

    1998-05-01

    The reduced growth hormone and insulin-like growth factor-I concentrations in growth hormone deficiency and normal ageing are associated with reduced muscle mass and strength, and slower muscle protein synthesis. Recent research has addressed the hypothesis that growth hormone and insulin-like growth factor-I have an anabolic effect in adults, including the elderly. These hormones stimulate whole-body and muscle protein synthesis, at least under some conditions. There is increasing evidence to justify long-term administration of growth hormone to promote muscle growth in growth hormone deficient adults. However, the long-term effects on muscle mass and function in the elderly do not seem beneficial enough to justify widespread hormone replacement therapy. These hormones may be useful anabolic agents to counteract muscle wasting under other conditions, including surgical stress, renal failure, muscular dystrophy, glucocorticoid administration and HIV infection, but more clinical trials are needed to determine the functional significance of the protein anabolic effects under these conditions.

  18. Growth factors for therapeutic angiogenesis in hypercholesterolemic erectile dysfunction

    Institute of Scientific and Technical Information of China (English)

    Donghua Xie; Brian H. Annex; Craig F. Donatucci

    2008-01-01

    The past decade has seen an explosion of new information on the physiology of penile erection, and pathophysiology of erectile dysfunction (ED). Hypercholesterolemia is a chronic condition that can lead to degeneration in the vasculature bed and can result in ED if the penile vasculature is involved. Angiogenesis is the growth of new blood vessels from preexisting vasculature. Therapeutic angiogenesis seeks to harness the mechanisms of vascular growth to treat disorders of inadequate tissue perfusion, such as coronary artery disease and ED. There have been tremendous changes in the field of therapeutic angiogenesis over the past decade, and there is much promise for the future.Initial preclinical work with cytokine growth factor delivery resulted in a great deal of enthusiasm for the treatment of ischemic heart and/or peripheral vascular disease, though clinical studies have not achieved similar success. With an increased understanding of the complex mechanisms involved in angiogenesis, novel therapies which target multiple different angiogenic pathways are also being developed and tested. The penis is a convenient tissue target for gene therapy because of its external location and accessibility, the ubiquity of endothelial lined spaces, and low level of blood flow, especially in the flaccid state. Therapeutic angiogenesis is an exciting field that continues to evolve. This review will focus on the development of growth factors for hypercholesterolemic ED, the use of various growth factors for ED therapy, their routes of delivery, and the results in animal studies.

  19. Growth factors/cytokines/defensins and apoptosis in periodontal pathologies.

    Science.gov (United States)

    Laurina, Zane; Pilmane, Mara; Care, Ruta

    2009-01-01

    In the recent past there has been an increased emphasis on morphogenetic tissue research of periodontal tissues. The aim of this study was to find qualitative and quantitative correlations in distribution and appearance of growth factors/cytokines/defensins and apoptosis in periodontal pathologies. Tissue was obtained from 5 controls and 6 chronical periodontitis patients 30-50 years of age referred to Latvian Institute of Stomatology. Histological investigations were performed at the Institute of Anatomy and Anthropology of Riga Stradins University. Epithelial cells abundantly expressed IL10 in patients. The expression of b-defensins was very variable in both sulcular and gingival epithelium. TUNEL positive cells were observed in patients and control specimens with dominance in control group. Gingival epithelium showed moderate expression of bFGF whereas few to moderate cells were positive for bFGF in sulcular epithelium. Fibroblast growth factor receptor (FGF-1R) was abundant in gingival epithelium and in connective tissue cells, but almost not detectable in sulcular epithelium. Insulin-like growth factor receptor was not expressed in gingival epithelium and was weakly seen in basal layer of sulcular epithelium. Basic nerve growth factor expresion in both types of epithelium was numerous to abundant. Staining for the NGFR in the gingival epithelium was variable, with prevalence to be moderate whereas sulcular epithelium was free from any factor immunoreactivity. 1. Finding of apoptotic cells are variable and seems to correlate with the expression of defensins in oral epithelium in patients with periodontitis. 2. FGFR was expressed more than the bFGF, but in case with NGFR and bNGF situation was opposite. Although IGFRI was found in sulcular epithelium with no expression in gingival one suggesting about stimulation in regeneration/adaptation in periodontitis affected tissue. 3. The expression of growth factors and their receptors in sulcular epithelium was lower

  20. Functional upregulation of system xc- by fibroblast growth factor-2.

    Science.gov (United States)

    Liu, Xiaoqian; Resch, Jon; Rush, Travis; Lobner, Doug

    2012-02-01

    The cystine/glutamate antiporter (system xc-) is a Na(+)-independent amino acid transport system. Disruption of this system may lead to multiple effects in the CNS including decreased cellular glutathione. Since multiple neurological diseases involve glutathione depletion, and disruption of growth factor signaling has also been implicated in these diseases, it is possible that some growth factors effects are mediated by regulation of system xc-. We tested the growth factors fibroblast growth factor-2 (FGF-2), insulin-like growth factor-1 (IGF-1), neuregulin-1 (NRG), neurotrophin-4 (NT-4), and brain derived neurotrophic factor (BDNF) on system xc- mediated 14C-cystine uptake in mixed neuronal and glial cortical cultures. Only FGF-2 significantly increased cystine uptake. The effect was observed in astrocyte-enriched cultures, but not in cultures of neurons or microglia. The increase was blocked by the system xc- inhibitor (s)-4-carboxyphenylglycine, required at least 12 h FGF-2 treatment, and was prevented by the protein synthesis inhibitor cycloheximide. Kinetic analysis indicated FGF-2 treatment increased the V(max) for cystine uptake while the K(m) remained the same. Quantitative PCR showed an increase in mRNA for xCT, the functional subunit of system xc-, beginning at 3 h of FGF-2 treatment, with a dramatic increase after 12 h. Blocking FGFR1 with PD 166866 blocked the FGF-2 effect. Treatment with a PI3-kinase inhibitor (LY-294002) or a MEK/ERK inhibitor (U0126) for 1 h prior to and during the FGF-2 treatment, each partially blocked the increased cystine uptake. The upregulation of system xc- by FGF-2 may be responsible for some of the known physiological actions of FGF-2. This article is part of a Special Issue entitled 'Post-Traumatic Stress Disorder'.

  1. Six Sigma: Problems, Limitations, Critical Success Factors and Future Prospects

    Directory of Open Access Journals (Sweden)

    Paulo Mazieiro Pohlmann

    2015-12-01

    Full Text Available Six Sigma is a business strategy based on objective decision making and problem solving in order to achieve, maintain and maximize business success through understanding and meeting the needs of customers. The visualization of this methodology as a powerful tool in reducing variability and improving quality led to the interest in performing this bibliographical study, whose purpose was to assess the critical success factors and future prospects of this managerial system. A survey was conducted in order to discover the main critical success factors of the implementation of the methodology in organizations, among which stood out the proper selection of projects, connecting the project with the business strategy, customer focus, financial, human and infrastructure resources, the involvement of senior management, professional training, and cultural change.

  2. The role of transforming growth factor beta in tertiary dentinogenesis

    Directory of Open Access Journals (Sweden)

    Tetiana Haniastuti

    2008-03-01

    Full Text Available The most visible repair response to pulp injury is the deposition of a tertiary dentin matrix over the dentinal tubules of the primary or secondary dentin. Tertiary dentin is distinguished as reactionary and reparative dentin, depending on the severity of the initiating response and the conditions under which the newly deposited dentin matrix was elaborated. Transforming growth factor beta (TGF-b superfamily is a large group of growth factors that serve important roles in regulating cell growth, differentiation, and function. Members of this superfamily have been implicated in the repair process of the dental tissue after injury. Although numerous studies have proved that those bioactive molecules carry out an important role in the formation of tertiary dentin, comprehensive report regarding that phenomenon is not yet available. This review article aimed to summarize the role of TGF-b on tertiary dentinogenesis during the progression of a carious lesion.

  3. Nerve growth factor: a novel mediator in asthma

    NARCIS (Netherlands)

    Vries, Annick de

    2001-01-01

    Nerve growth factor (NGF) is known for years for its properties to induce neurite outgrowth. Its role in inflammation has recently been discovered. In this thesis the role of NGF in allergic asthma is shown. In chapter 2 we showed that NGF can induce airway hyperresponsiveness in guinea pigs. Sim

  4. Vascular endothelial growth factor a in eyes with uveal melanoma.

    NARCIS (Netherlands)

    Missotten, G.S.; Notting, I.C.; Schlingemann, R.O.; Zijlmans, H.J.; Lau, C.; Eilers, P.H.; Keunen, J.E.E.; Jager, M.J.

    2006-01-01

    OBJECTIVES: To determine the presence of vascular endothelial growth factor A (VEGF-A) in the aqueous humor of eyes with uveal melanoma and to identify its source. METHODS: The VEGF-A concentrations were determined in aqueous humor samples obtained after enucleation from 74 eyes with untreated uveal

  5. Plasma transforming growth factor beta levels in breast cancer patients

    NARCIS (Netherlands)

    Sminia, P; Barten, AD; Van Waarde, MAWH; Vujaskovic, Z; Van Tienhoven, G

    1998-01-01

    We investigated whether the concentration of circulating transforming growth factor beta (TGF beta) yields diagnostic value in breast cancer. Blood was collected from twenty stage I and II breast cancer patients both prior to treatment and after surgical excision of the tumour. Both latent and activ

  6. Fibroblast Growth Factor-2 Alters the Nature of Extinction

    Science.gov (United States)

    Graham, Bronwyn M.; Richardson, Rick

    2011-01-01

    These experiments examined the effects of the NMDA-receptor (NMDAr) antagonist MK801 on reacquisition and re-extinction of a conditioned fear that had been previously extinguished before injection of fibroblast growth factor-2 (FGF2) or vehicle. Recent findings have shown that relearning and re-extinction, unlike initial learning and extinction,…

  7. Gastric luminal epidermal growth factor is affected by diet

    African Journals Online (AJOL)

    vegetable,' and on contaminants in the diet such as fumonisins.' The first ... with low dietary intake of animal products (p = 0.002) and vegetables (p .... had an effect on EGF since a non-significant difference was seen. Vegetable .... growth factor administration on intestinal cell proliferation, crypt Ossion and polyp formation in ...

  8. Epidermal growth factor receptor expression in urinary bladder cancer

    Directory of Open Access Journals (Sweden)

    Dayalu S.L. Naik

    2011-01-01

    Full Text Available Objective : To evaluate the expression pattern of epidermal growth factor receptor (EGFR in urinary bladder cancer and its association with human epidermal growth factor receptor 2 (HER2, epidermal growth factor (EGF, interleukin-6 (IL-6, and high risk human papilloma virus (HPV types 16 and 18. Materials and Methods : Thirty cases of urothelial carcinoma were analyzed. EGFR, HER2, EGF, and IL-6 expressions in the tissue were evaluated by immunohistochemical staining. For HPV, DNA from tissue samples was extracted and detection of HPV was done by PCR technique. Furthermore, evaluation of different intracellular molecules associated with EGFR signaling pathways was performed by the western blot method using lysates from various cells and tissues. Results : In this study, the frequencies of immunopositivity for EGFR, HER2, EGF, and IL-6 were 23%, 60%, 47%, and 80%, respectively. No cases were positive for HPV-18, whereas HPV-16 was detected in 10% cases. Overall, expression of EGFR did not show any statistically significant association with the studied parameters. However, among male patients, a significant association was found only between EGFR and HER2. Conclusions : Overexpression of EGFR and/or HER2, two important members of the same family of growth factor receptors, was observed in a considerable proportion of cases. Precise knowledge in this subject would be helpful to formulate a rational treatment strategy in patients with urinary bladder cancer.

  9. Chemical strategies for the presentation and delivery of growth factors

    NARCIS (Netherlands)

    Cabanas Danés, Jordi; Huskens, Jurriaan; Jonkheijm, Pascal

    2014-01-01

    Since the first demonstration of employing growth factors (GFs) to control cell behaviour in vitro, the spatiotemporal availability of GFs in vivo has received continuous attention. In particular, the ability to physically confine the mobility of GFs has been used in various tissue engineering

  10. Signal transduction by growth factor receptors: signaling in an instant

    DEFF Research Database (Denmark)

    Dengjel, Joern; Akimov, Vyacheslav; Blagoev, Blagoy;

    2007-01-01

    -out by mass spectrometry-based proteomics has allowed exciting views on the very early events in signal transduction. Activation profiles of regulated phosphorylation sites on epidermal growth factor receptor and downstream signal transducers showed different kinetics within the first ten seconds...

  11. Regulation of mechano growth factor in skeletal muscle and heart

    NARCIS (Netherlands)

    Ottens, M.

    2010-01-01

    The mechano growth factor (MGF) is expressed in mechanically overloaded skeletal muscle. MGF was discovered in 1996 as an alternative splice product of the IGF-1 gene. Since then, its significance has been investigated particularly in skeletal muscle, because the local expression of MGF could

  12. Extra nodal growth as a prognostic factor in malignant melanoma

    NARCIS (Netherlands)

    Koopal, SA; Tiebosch, ATMG; Daryanani, D; Plukker, JTM; Hoekstra, HJ

    Aim. Extra nodal growth (ENG) in lymph-node metastases may be an additional. indicator for poor prognosis and increased Loco-regional recurrence in patients with a cutaneous malignant melanoma (CMM). Most studies analyzing prognostic factors tack a proper definition or description of the

  13. Modulation of gap junction channels and hemichannels by growth factors.

    Science.gov (United States)

    Schalper, Kurt A; Riquelme, Manuel A; Brañes, María C; Martínez, Agustín D; Vega, José Luis; Berthoud, Viviana M; Bennett, Michael V L; Sáez, Juan C

    2012-03-01

    Gap junction hemichannels and cell-cell channels have roles in coordinating numerous cellular processes, due to their permeability to extra and intracellular signaling molecules. Another mechanism of cellular coordination is provided by a vast array of growth factors that interact with relatively selective cell membrane receptors. These receptors can affect cellular transduction pathways, including alteration of intracellular concentration of free Ca(2+) and free radicals and activation of protein kinases or phosphatases. Connexin and pannexin based channels constitute recently described targets of growth factor signal transduction pathways, but little is known regarding the effects of growth factor signaling on pannexin based channels. The effects of growth factors on these two channel types seem to depend on the cell type, cell stage and connexin and pannexin isoform expressed. The functional state of hemichannels and gap junction channels are affected in opposite directions by FGF-1 via protein kinase-dependent mechanisms. These changes are largely explained by channels insertion in or withdrawal from the cell membrane, but changes in open probability might also occur due to changes in phosphorylation and redox state of channel subunits. The functional consequence of variation in cell-cell communication via these membrane channels is implicated in disease as well as normal cellular responses.

  14. Circulating vascular endothelial growth factor during the normal menstrual cycle

    NARCIS (Netherlands)

    Kusumanto, YH; Hospers, GAP; Sluiter, WJ; Dam, WA; Meijer, C; Mulder, NH

    2004-01-01

    Background: The purpose of the study was to investigate whether cycle-related variations in circulating Vascular Endothelial Growth Factor (VEGF) levels would increase the metastatic potential at specific times during the menstrual cycle. Materials and Methods: VEGF levels in serum and whole blood

  15. Role of fibroblast growth factors in organ regeneration and repair.

    Science.gov (United States)

    El Agha, Elie; Kosanovic, Djuro; Schermuly, Ralph T; Bellusci, Saverio

    2016-05-01

    In its broad sense, regeneration refers to the renewal of lost cells, tissues or organs as part of the normal life cycle (skin, hair, endometrium etc.) or as part of an adaptive mechanism that organisms have developed throughout evolution. For example, worms, starfish and amphibians have developed remarkable regenerative capabilities allowing them to voluntarily shed body parts, in a process called autotomy, only to replace the lost parts afterwards. The bizarre myth of the fireproof homicidal salamander that can survive fire and poison apple trees has persisted until the 20th century. Salamanders possess one of the most robust regenerative machineries in vertebrates and attempting to draw lessons from limb regeneration in these animals and extrapolate the knowledge to mammals is a never-ending endeavor. Fibroblast growth factors are potent morphogens and mitogens that are highly conserved among the animal kingdom. These growth factors play key roles in organogenesis during embryonic development as well as homeostatic balance during postnatal life. In this review, we provide a summary about the current knowledge regarding the involvement of fibroblast growth factor signaling in organ regeneration and repair. We also shed light on the use of these growth factors in previous and current clinical trials in a wide array of human diseases.

  16. The epidermal growth factor receptor pathway in chronic kidney diseases

    NARCIS (Netherlands)

    Harskamp, Laura R.; Gansevoort, Ron T.; Goor, van Harry; Meijer, Esther

    2016-01-01

    The epidermal growth factor receptor (EGFR) pathway has a critical role in renal development, tissue repair and electrolyte handling. Numerous studies have reported an association between dysregulation of this pathway and the initiation and progression of various chronic kidney diseases such as diab

  17. Circulating vascular endothelial growth factor during the normal menstrual cycle

    NARCIS (Netherlands)

    Kusumanto, YH; Hospers, GAP; Sluiter, WJ; Dam, WA; Meijer, C; Mulder, NH

    2004-01-01

    Background: The purpose of the study was to investigate whether cycle-related variations in circulating Vascular Endothelial Growth Factor (VEGF) levels would increase the metastatic potential at specific times during the menstrual cycle. Materials and Methods: VEGF levels in serum and whole blood w

  18. Regulation of mechano growth factor in skeletal muscle and heart

    NARCIS (Netherlands)

    Ottens, M.

    2010-01-01

    The mechano growth factor (MGF) is expressed in mechanically overloaded skeletal muscle. MGF was discovered in 1996 as an alternative splice product of the IGF-1 gene. Since then, its significance has been investigated particularly in skeletal muscle, because the local expression of MGF could provid

  19. Epidermal growth factor receptor: Target for delivery and silencing

    NARCIS (Netherlands)

    Santos Oliveira, S.

    2008-01-01

    Epidermal growth factor receptor in cancer therapy Recently, cancer research has been able to identify molecular targets that are specific for (or highly expressed by) cancer cells. These molecular targets serve as models for the development of rationally designed anticancer drugs that target import

  20. Immunocytochemical expression of growth factors by odontogenic jaw cysts.

    Science.gov (United States)

    Li, T.; Browne, R. M.; Matthews, J. B.

    1997-01-01

    AIM: To determine the immunocytochemical pattern of expression of transforming growth factor (TGF) alpha, epidermal growth factor (EGF), and TGF beta in the three most common types of odontogenic jaw cyst. METHODS: Growth factor expression was detected in paraffin wax sections of odontogenic cysts (27 odontogenic keratocysts, 10 dentigerous cysts, and 10 radicular cysts) using a streptavidin-biotin peroxidase technique with monoclonal antibodies directed against TGF alpha (clone 213-4.4) and TGF beta (clone TB21) and a polyclonal antibody directed against EGF (Z-12). RESULTS: The epithelial linings of all cysts showed reactivity for TGF alpha which was mainly localised to basal and suprabasal layers. Odontogenic keratocyst linings expressed higher levels of TGF alpha than those of dentigerous and radicular cysts, with 89% (24/27) of odontogenic keratocysts exhibiting a strong positive reaction compared with 50% (five of 10) of dentigerous and radicular cysts, respectively. EGF reactivity was similar in all cyst groups, weaker than that for TGF alpha and predominantly suprabasal. TGF alpha and EGF were also detected in endothelial cells, fibroblasts and inflammatory cells within the cyst walls. The most intense TGF beta staining in odontogenic cysts was extracellular within the fibrous tissue capsules, irrespective of cyst type. CONCLUSIONS: These results, together with previous studies of EGF receptor, indicate differential expression of TGF alpha, EGF and their common receptor between the different types of odontogenic cyst, suggesting that these growth factors (via autocrine or paracrine, or both, pathways) may be involved in their pathogenesis. Images PMID:9208810

  1. Immunolocalization of transforming growth factor alpha in normal human tissues

    DEFF Research Database (Denmark)

    Christensen, M E; Poulsen, Steen Seier

    1996-01-01

    the distribution of the growth factor in a broad spectrum of normal human tissues. Indirect immunoenzymatic staining methods were used. The polypeptide was detected with a polyclonal as well as a monoclonal antibody. The polyclonal and monoclonal antibodies demonstrated almost identical immunoreactivity. TGF...

  2. Controlled growth factor release from synthetic extracellular matrices

    Science.gov (United States)

    Lee, Kuen Yong; Peters, Martin C.; Anderson, Kenneth W.; Mooney, David J.

    2000-12-01

    Polymeric matrices can be used to grow new tissues and organs, and the delivery of growth factors from these matrices is one method to regenerate tissues. A problem with engineering tissues that exist in a mechanically dynamic environment, such as bone, muscle and blood vessels, is that most drug delivery systems have been designed to operate under static conditions. We thought that polymeric matrices, which release growth factors in response to mechanical signals, might provide a new approach to guide tissue formation in mechanically stressed environments. Critical design features for this type of system include the ability to undergo repeated deformation, and a reversible binding of the protein growth factors to polymeric matrices to allow for responses to repeated stimuli. Here we report a model delivery system that can respond to mechanical signalling and upregulate the release of a growth factor to promote blood vessel formation. This approach may find a number of applications, including regeneration and engineering of new tissues and more general drug-delivery applications.

  3. Over-limiting Current and Control of Dendritic Growth by Surface Conduction in Nanopores

    CERN Document Server

    Han, Ji-Hyung; Bai, Peng; Bazant, Martin Z

    2014-01-01

    Understanding over-limiting current (faster than diffusion) is a long-standing challenge in electrochemistry with applications in desalination and energy storage. Known mechanisms involve either chemical or hydrodynamic instabilities in unconfined electrolytes. Here, it is shown that over-limiting current can be sustained by surface conduction in nano pores, without any such instabilities, and used to control dendritic growth during electrodeposition. Copper electrode posits are grown in anodized aluminum oxide membranes with polyelectrolyte coatings to modify the surface charge. At low currents, uniform electroplating occurs, unaffected by surface modification due to thin electric double layers, but the morphology changes dramatically above the limiting current. With negative surface charge, growth is enhanced along the nanopore surfaces, forming surface dendrites and nanotubes behind a deionization shock. With positive surface charge, dendrites avoid the surfaces and are either guided along the nanopore cen...

  4. Novel polymeric scaffolds using protein microbubbles as porogen and growth factor carriers.

    Science.gov (United States)

    Nair, Ashwin; Thevenot, Paul; Dey, Jagannath; Shen, Jinhui; Sun, Man-Wu; Yang, Jian; Tang, Liping

    2010-02-01

    Polymeric tissue engineering scaffolds prepared by conventional techniques like salt leaching and phase separation are greatly limited by their poor biomolecule-delivery abilities. Conventional methods of incorporation of various growth factors, proteins, and/or peptides on or in scaffold materials via different crosslinking and conjugation techniques are often tedious and may affect scaffold's physical, chemical, and mechanical properties. To overcome such deficiencies, a novel two-step porous scaffold fabrication procedure has been created in which bovine serum albumin microbubbles (henceforth MB) were used as porogen and growth factor carriers. Polymer solution mixed with MB was phase separated and then lyophilized to create porous scaffold. MB scaffold triggered substantially lesser inflammatory responses than salt-leached and conventional phase-separated scaffolds in vivo. Most importantly, the same technique was used to produce insulin-like growth factor-1 (IGF-1)-eluting porous scaffolds, simply by incorporating IGF-1-loaded MB (MB-IGF-1) with polymer solution before phase separation. In vitro such MB-IGF-1 scaffolds were able to promote cell growth to a much greater extent than scaffold soaked in IGF-1, confirming the bioactivity of the released IGF-1. Further, such MB-IGF-1 scaffolds elicited IGF-1-specific collagen production in the surrounding tissue in vivo. This novel growth factor-eluting scaffold fabrication procedure can be used to deliver a range of single or combination of bioactive biomolecules to substantially promote cell growth and function in degradable scaffold.

  5. Fetal effects of epidermal growth factor deficiency induced in rats by autoantibodies against epidermal growth factor

    DEFF Research Database (Denmark)

    Raaberg, Lasse; Nexø, Ebba; Jørgensen, P E

    1995-01-01

    , the amount of surfactant protein-A was decreased, suggesting a delayed lung maturation. The offspring of EGF-immunized rats had dry and wrinkled skin. The skin was thin and the hair follicles were immature. This suggests a role for EGF in the growth and development of the skin. The liver/body weight ratio...

  6. Auxins as one of the factors of plant growth improvement by plant growth promoting rhizobacteria.

    Science.gov (United States)

    Ahmed, Ambreen; Hasnain, Shahida

    2014-01-01

    Plant growth promoting rhizobacteria (PGPR) promote plant growth by various mechanisms such as phytohormone production, enhanced water and nutrient uptake, improved nitrogen availability in the soil, production of ACC-deaminase for ethylene breakdown, phosphate solubilization, siderophore production etc. Microbial auxin production is the major factor not only responsible for strengthening the plant-microbe relationship but it also promotes plant growth and development in a positive manner. Thus, bacterial auxin production potential can be exploited for plant growth improvement that may be effective in reducing the hazardous effects of chemical fertilizers on the ecosystem used to obtain higher yields. The present review gives a better understanding of various factors and mechanisms involved in auxin production by PGPR that may be helpful in proper exploitation of these natural resources in a beneficial way.

  7. Stimulation of body weight increase and epiphyseal cartilage growth by insulin like growth factor

    Science.gov (United States)

    Ellis, S.

    1981-01-01

    The ability of insulin-like growth factor (IGF) to induce growth in hypophysectomized immature rats was tested by continuous infusion of the partially purified factor at daily doses of 6, 21, and 46 mU for an 8-day period. A dose-dependent growth of the proximal epiphyseal cartilage of the tibia and an associated stimulation of the primary spongiosa were produced by these amounts of IGF. The two highest doses of IGF also resulted in dose-dependent increases of body weight. Gel permeation of the sera at neutrality showed that the large-molecular-weight IGF binding protein was not induced by the infusion of IGF, whereas it ws generated in the sera of hypophysectomized rats that were infused with daily doses of 86 mU of human growth hormone.

  8. Steady impact factor growth for MDPI open access journals.

    Science.gov (United States)

    Thiesen, Alexander

    2012-09-12

    For the past three years MDPI has announced the newly released impact factors for its Open Access journals by the means of an annual editorial [1-3]. In 2012 we are-once again-pleased to report that the growth of the impact factors of MDPI's Open Access journals continues. This year's edition of the Journal Citation Reports (JCR), which is published annually by Thomson Reuters, includes 10 journals published by MDPI, including three that have received their first official Impact Factors- International Journal of Environmental Research and Public Health (IJERPH), Materials Nutrients. Table 1 reports the latest Impact Factors for 2011. Figure 1 graphically depicts the evolution of the Impact Factors for four MDPI open access journals that have received Impact Factors in the past. Table 2 reports the ranking of the MDPI journals within the subject categories of the Science Citation Index Expanded.

  9. Autocrine growth regulation of human glomerular mesangial cells is primarily mediated by basic fibroblast growth factor.

    OpenAIRE

    Francki, A.; Uciechowski, P.; Floege, J; von der Ohe, J.; Resch, K.; Radeke, H. H.

    1995-01-01

    For various forms of human glomerulonephritis a close relationship between inflammatory injury and a local mesangial proliferative response has been described. Herein, we used primary cultures of human glomerular mesangial cells (HMCs) from five different donors to determine the autocrine growth-inducing capacity of their supernatants after stimulation with different cytokines and lipopolysaccharide (LPS) to determine whether this effect is due to basic fibroblast growth factor (bFGF). The ba...

  10. Limiting factors to advancing thermal battery technology for naval applications

    Science.gov (United States)

    Davis, Patrick B.; Winchester, Clinton S.

    1991-10-01

    Thermal batteries are primary reserve electrochemical power sources using molten salt electrolyte which experience little effective aging while in storage or dormant deployment. Thermal batteries are primarily used in military applications, and are currently used in a wide variety of Navy devices such as missiles, torpedoes, decays, and training targets, usually as power supplies in guidance, propulsion, and Safe/Arm applications. Technology developments have increased the available energy and power density ratings by an order of magnitude in the last ten years. Present thermal batteries, using lithium anodes and metal sulfide cathodes, are capable of performing applications where only less rugged and more expensive silver oxide/zinc or silver/magnesium chloride seawater batteries could serve previously. Additionally, these batteries are capable of supplanting lithium/thionyl chloride reserve batteries in a variety of specifically optimized designs. Increases in thermal battery energy and power density capabilities are not projected to continue with the current available technology. Several battery designs are now at the edge of feasibility and safety. Since future naval systems are likely to require continued growth of battery energy and power densities, there must be significant advances in battery technology. Specifically, anode alloy composition and new cathode materials must be investigated to allow for safe development and deployment of these high power, higher energy density batteries.

  11. Transforming growth factor beta (TGF-β) in milk: a review

    OpenAIRE

    Fernanda Lopes da Silva; Michele da Silva Pinto; Antônio Fernandes Carvalho; Ítalo Tuler Perrone

    2016-01-01

    Bovine milk and colostrum contain growth factors such as insulin-like growth factor IGF-I, IGF-II, transforming growth factor TGF-β1, TGF-β2, epidermal growth factor EGF, basic fibroblast growth factor bFGF and platelet-derived growth factor PDGF. In recent years, intense scientific interest has been focused on the identification of factors within bovine milk that may be relevant to improving human health. Then a number of methodologies for the extraction of milk growth factors from milk, col...

  12. Expression of protooncogenes during lymphocyte activation by growth factors.

    Science.gov (United States)

    Bulanova, E G; Budagyan, V M; Yarilin, A A; Mazurenko, N N

    1997-09-01

    Effects of growth factors of non-immune origin including somatotropin (ST) and platelet-derived growth factor (PDGF) on the expression of the proteins encoded by c-fos, c-myc, c-fun, and c-ets family protooncogenes were studied for the first time. The dynamics of the oncoprotein expression in activated CD(3+)-lymphocytes was investigated by immunoblotting. The accumulation of the Fos and Myc proteins was enhanced in T-lymphocytes treated with ST, PDGF, or phytohemagglutinin; the accumulation was maximum at 30-60 min and decreased in 2 h; the data indicate that the oncoproteins participate in the early lymphocyte activation by various growth factors. The Jun protein appears only in 3 h after the onset of lymphocyte activation; this suggests independent participation of Fos in the early stages of lymphocyte activation prior to the appearance of Jun, preceding the joint action of Fos and Jun within the AP-1 transcription complex. The products of the c-ets family are differentially activated by the studied growth factors. Resting lymphocytes actively accumulate the Ets-1 protein; ST and PDGF activation decreases Ets-1 expression in 2 h. The Ets-2 protein is not detected in resting cells and PDGF-activated lymphocytes, whereas lymphocyte activation by ST is associated with accumulation of Ets-2. The data suggest that the product of the c-ets-1 gene is more important in the regulation of resting cells and the product of the c-ets-2 gene is important during activation of lymphocytes by ST. The results indicate that activation of lymphocytes with growth factors of non-immune origin is mediated by several signal transduction pathways.

  13. Gelatin methacrylate microspheres for controlled growth factor release.

    Science.gov (United States)

    Nguyen, Anh H; McKinney, Jay; Miller, Tobias; Bongiorno, Tom; McDevitt, Todd C

    2015-02-01

    Gelatin has been commonly used as a delivery vehicle for various biomolecules for tissue engineering and regenerative medicine applications due to its simple fabrication methods, inherent electrostatic binding properties, and proteolytic degradability. Compared to traditional chemical cross-linking methods, such as the use of glutaraldehyde (GA), methacrylate modification of gelatin offers an alternative method to better control the extent of hydrogel cross-linking. Here we examined the physical properties and growth factor delivery of gelatin methacrylate (GMA) microparticles (MPs) formulated with a wide range of different cross-linking densities (15-90%). Less methacrylated MPs had decreased elastic moduli and larger mesh sizes compared to GA MPs, with increasing methacrylation correlating to greater moduli and smaller mesh sizes. As expected, an inverse correlation between microparticle cross-linking density and degradation was observed, with the lowest cross-linked GMA MPs degrading at the fastest rate, comparable to GA MPs. Interestingly, GMA MPs at lower cross-linking densities could be loaded with up to a 10-fold higher relative amount of growth factor than conventional GA cross-linked MPs, despite the GA MPs having an order of magnitude greater gelatin content. Moreover, a reduced GMA cross-linking density resulted in more complete release of bone morphogenic protein 4 and basic fibroblast growth factor and accelerated release rate with collagenase treatment. These studies demonstrate that GMA MPs provide a more flexible platform for growth factor delivery by enhancing the relative binding capacity and permitting proteolytic degradation tunability, thereby offering a more potent controlled release system for growth factor delivery.

  14. Towards lag phase of microbial populations at growth-limiting conditions: The role of the variability in the growth limits of individual cells.

    Science.gov (United States)

    Aguirre, Juan S; Koutsoumanis, Konstantinos P

    2016-05-02

    The water activity (aw) growth limits of unheated and heat stressed Listeria monocytogenes individual cells were studied. The aw limits varied from 0.940 to 0.997 and 0.951 to 0.997 for unheated and heat stressed cells, respectively. Due to the above variability a decrease in aw results in the presence of a non-growing fraction in the population leading to an additional pseudo-lag in population growth. In this case the total apparent lag of the population is the sum of the physiological lag of the growing cells (time required to adjust to the new environment) and the pseudo-lag. To investigate the effect of aw on the above lag components, the growth kinetics of L. monocytogenes on tryptone soy agar with aw adjusted to values ranging from 0.997 to 0.940 was monitored. The model of B&R was fitted to the data for the estimation of the apparent lag. In order to estimate the physiological lag of the growing fraction of the inoculum, the model was refitted to the growth data using as initial population level the number of cells that were able to grow (estimated from the number of colonies formed on the agar at the end of storage) and excluding the rest data during the lag. The results showed that for the unheated cells the apparent lag was almost identical to the physiological lag for aw values ranging from 0.997 to 0.970, as the majority of the cells in the initial population was able to grow in these conditions. As the aw decreased from 0.970 to 0.940 however, the number of cells in the population which were able to grow, decreased resulting to an increase in the pseudo-lag. The maximum value of pseudo-lag was 13.1h and it was observed at aw=0.940 where 10% of the total inoculated cells were able to grow. For heat stressed populations a pseudo-lag started to increase at higher aw conditions (0.982) compared to unheated cells. In contrast to the apparent lag, a linear relation between physiological lag and aw was observed for both unheated and heat stressed cells.

  15. Decreased plasma brain-derived neurotrophic factor and vascular endothelial growth factor concentrations during military training.

    Directory of Open Access Journals (Sweden)

    Go Suzuki

    Full Text Available Decreased concentrations of plasma brain-derived neurotrophic factor (BDNF and serum BDNF have been proposed to be a state marker of depression and a biological indicator of loaded psychosocial stress. Stress evaluations of participants in military mission are critically important and appropriate objective biological parameters that evaluate stress are needed. In military circumstances, there are several problems to adopt plasma BDNF concentration as a stress biomarker. First, in addition to psychosocial stress, military missions inevitably involve physical exercise that increases plasma BDNF concentrations. Second, most participants in the mission do not have adequate quality or quantity of sleep, and sleep deprivation has also been reported to increase plasma BDNF concentration. We evaluated plasma BDNF concentrations in 52 participants on a 9-week military mission. The present study revealed that plasma BDNF concentration significantly decreased despite elevated serum enzymes that escaped from muscle and decreased quantity and quality of sleep, as detected by a wearable watch-type sensor. In addition, we observed a significant decrease in plasma vascular endothelial growth factor (VEGF during the mission. VEGF is also neurotrophic and its expression in the brain has been reported to be up-regulated by antidepressive treatments and down-regulated by stress. This is the first report of decreased plasma VEGF concentrations by stress. We conclude that decreased plasma concentrations of neurotrophins can be candidates for mental stress indicators in actual stressful environments that include physical exercise and limited sleep.

  16. Nerve growth factor promotes in vitro proliferation of neural stem cells from tree shrews

    Directory of Open Access Journals (Sweden)

    Liu-lin Xiong

    2016-01-01

    Full Text Available Neural stem cells promote neuronal regeneration and repair of brain tissue after injury, but have limited resources and proliferative ability in vivo. We hypothesized that nerve growth factor would promote in vitro proliferation of neural stem cells derived from the tree shrews, a primate-like mammal that has been proposed as an alternative to primates in biomedical translational research. We cultured neural stem cells from the hippocampus of tree shrews at embryonic day 38, and added nerve growth factor (100 µg/L to the culture medium. Neural stem cells from the hippocampus of tree shrews cultured without nerve growth factor were used as controls. After 3 days, fluorescence microscopy after DAPI and nestin staining revealed that the number of neurospheres and DAPI/nestin-positive cells was markedly greater in the nerve growth factor-treated cells than in control cells. These findings demonstrate that nerve growth factor promotes the proliferation of neural stem cells derived from tree shrews.

  17. Rate limiting factors in trichloroethylene co-metabolic degradation by phenol-grown aerobic granules.

    Science.gov (United States)

    Zhang, Yi; Tay, Joo Hwa

    2014-04-01

    The potential of aerobic granular sludge in co-metabolic removal of recalcitrant substances was evaluated using trichloroethylene (TCE) as the model compound. Aerobic granules cultivated in a sequencing batch reactor with phenol as the growth substrate exhibited TCE and phenol degradation activities lower than previously reported values. Depletion of reducing energy and diffusion limitation within the granules were investigated as the possible rate limiting factors. Sodium formate and citrate were supplied to the granules in batch studies as external electron sources. No significant enhancing effect was observed on the instant TCE transformation rates, but 10 mM formate could improve the ultimate transformation capacity by 26 %. Possible diffusion barrier was studied by sieving the biomass into five size fractions, and determining their specific TCE and phenol degradation rates and capacities. Biomass in the larger size fractions generally showed lower activities. Large granules of >700 μm diameter exhibited only 22 % of the flocs' TCE transformation capacity and 35 % of its phenol dependent SOUR, indicating the possible occurrence of diffusion limitation in larger biomass. However, the highest specific TCE transformation rate was observed with the fraction that mostly consisted of small granules (150-300 μm), suggesting an optimal size range while applying aerobic granules in TCE co-metabolic removal.

  18. Factors affecting growth and pigmentation of Penicillium caseifulvum

    DEFF Research Database (Denmark)

    Suhr, Karin Isabel; Haasum, I.; Steenstrup, L.D.

    2002-01-01

    Color formation, metabolite production and growth of Penicillium caseifulvum were studied in order to elucidate factors contributing to. yellow discoloration of Blue Cheese caused by the mold. A screening experiment was set up to study the effect of pH, concentration of salt (NaCl), P, K, N, S, Mg...... the factors contributing to yellow color formation, pH and salt concentration are easy to control for the cheesemaker, while the third factor, P-concentration, is not. Naturally occurring variations in the P-concentration in milk delivered to Blue Cheese plants, could be responsible for the yellow...

  19. Prognosis and risk factors for intrauterine growth retardation

    DEFF Research Database (Denmark)

    Sehested, Line Thousig; Pedersen, Pernille

    2014-01-01

    focusing on risk factors, catch up and neonatal outcome. MATERIAL AND METHODS: This was a retrospective descriptive study of IUGR neonates with a birth weight below 70% of the expected whose mothers were admitted to the Neonatal Ward at Hvidovre Hospital during 2007-2009. Obstetrical and maternal risk...... factors and neonatal growth and outcome at six weeks, five months and 12 months of age were collected. RESULTS: A total of 73 neonates and their mothers were included. Caesarean delivery was given in 78% of the cases. Maternal risk factors included gestational hypertension (33%), smoking (24...

  20. Height-related growth declines in ponderosa pine are not due to carbon limitation.

    Science.gov (United States)

    Sala, Anna; Hoch, Günter

    2009-01-01

    Decreased gas exchange as trees grow tall has been proposed to explain age-related growth declines in trees. We examined changes of mobile carbon stores (starch, sugars and lipids) with tree height in ponderosa pine (Pinus ponderosa) at two sites differing in water availability, and tested the following hypotheses: (1) carbon supply does not become increasingly limited as trees grow tall; rather, the concentration of mobile carbon compounds increases with tree height reflecting greater reductions of carbon sink activities relative to carbon assimilation; and (2) increases of stored mobile carbon compounds with tree height are greater in drier sites. Height-related growth reductions were associated with significant increases of non-structural carbohydrates (NSC) and lipid concentrations in all tissues in the upper canopy and of NSC in the bole. Lipid concentrations in the bole decreased with tree height, but such decrease is not necessarily inconsistent with non-limiting carbon supply in tall trees. Furthermore, we found stronger increases of mobile carbon stores with tree height at the dry site relative to the moist site. Our results provide first direct evidence that carbon supply does not limit growth in tall trees and that decreases of water availability might negatively impact growth processes more than net-photosynthesis.

  1. Fast growth increases the selective advantage of a mutation arising recurrently during evolution under metal limitation.

    Directory of Open Access Journals (Sweden)

    Hsin-Hung Chou

    2009-09-01

    Full Text Available Understanding the evolution of biological systems requires untangling the molecular mechanisms that connect genetic and environmental variations to their physiological consequences. Metal limitation across many environments, ranging from pathogens in the human body to phytoplankton in the oceans, imposes strong selection for improved metal acquisition systems. In this study, we uncovered the genetic and physiological basis of adaptation to metal limitation using experimental populations of Methylobacterium extorquens AM1 evolved in metal-deficient growth media. We identified a transposition mutation arising recurrently in 30 of 32 independent populations that utilized methanol as a carbon source, but not in any of the 8 that utilized only succinate. These parallel insertion events increased expression of a novel transporter system that enhanced cobalt uptake. Such ability ensured the production of vitamin B(12, a cobalt-containing cofactor, to sustain two vitamin B(12-dependent enzymatic reactions essential to methanol, but not succinate, metabolism. Interestingly, this mutation provided higher selective advantages under genetic backgrounds or incubation temperatures that permit faster growth, indicating growth-rate-dependent epistatic and genotype-by-environment interactions. Our results link beneficial mutations emerging in a metal-limiting environment to their physiological basis in carbon metabolism, suggest that certain molecular features may promote the emergence of parallel mutations, and indicate that the selective advantages of some mutations depend generically upon changes in growth rate that can stem from either genetic or environmental influences.

  2. Fast growth increases the selective advantage of a mutation arising recurrently during evolution under metal limitation.

    Science.gov (United States)

    Chou, Hsin-Hung; Berthet, Julia; Marx, Christopher J

    2009-09-01

    Understanding the evolution of biological systems requires untangling the molecular mechanisms that connect genetic and environmental variations to their physiological consequences. Metal limitation across many environments, ranging from pathogens in the human body to phytoplankton in the oceans, imposes strong selection for improved metal acquisition systems. In this study, we uncovered the genetic and physiological basis of adaptation to metal limitation using experimental populations of Methylobacterium extorquens AM1 evolved in metal-deficient growth media. We identified a transposition mutation arising recurrently in 30 of 32 independent populations that utilized methanol as a carbon source, but not in any of the 8 that utilized only succinate. These parallel insertion events increased expression of a novel transporter system that enhanced cobalt uptake. Such ability ensured the production of vitamin B(12), a cobalt-containing cofactor, to sustain two vitamin B(12)-dependent enzymatic reactions essential to methanol, but not succinate, metabolism. Interestingly, this mutation provided higher selective advantages under genetic backgrounds or incubation temperatures that permit faster growth, indicating growth-rate-dependent epistatic and genotype-by-environment interactions. Our results link beneficial mutations emerging in a metal-limiting environment to their physiological basis in carbon metabolism, suggest that certain molecular features may promote the emergence of parallel mutations, and indicate that the selective advantages of some mutations depend generically upon changes in growth rate that can stem from either genetic or environmental influences.

  3. Rapid increase in fibroblast growth factor 21 in protein malnutrition and its impact on growth and lipid metabolism.

    Science.gov (United States)

    Ozaki, Yori; Saito, Kenji; Nakazawa, Kyoko; Konishi, Morichika; Itoh, Nobuyuki; Hakuno, Fumihiko; Takahashi, Shin-Ichiro; Kato, Hisanori; Takenaka, Asako

    2015-11-14

    Protein malnutrition promotes hepatic steatosis, decreases insulin-like growth factor (IGF)-I production and retards growth. To identify new molecules involved in such changes, we conducted DNA microarray analysis on liver samples from rats fed an isoenergetic low-protein diet for 8 h. We identified the fibroblast growth factor 21 gene (Fgf21) as one of the most strongly up-regulated genes under conditions of acute protein malnutrition (P<0·05, false-discovery rate<0·001). In addition, amino acid deprivation increased Fgf21 mRNA levels in rat liver-derived RL-34 cells (P<0·01). These results suggested that amino acid limitation directly increases Fgf21 expression. FGF21 is a polypeptide hormone that regulates glucose and lipid metabolism. FGF21 also promotes a growth hormone-resistance state and suppresses IGF-I in transgenic mice. Therefore, to determine further whether Fgf21 up-regulation causes hepatic steatosis and growth retardation after IGF-I decrease in protein malnutrition, we fed an isoenergetic low-protein diet to Fgf21-knockout (KO) mice. Fgf21-KO did not rescue growth retardation and reduced plasma IGF-I concentration in these mice. Fgf21-KO mice showed greater epididymal white adipose tissue weight and increased hepatic TAG and cholesterol levels under protein malnutrition conditions (P<0·05). Overall, the results showed that protein deprivation directly increased Fgf21 expression. However, growth retardation and decreased IGF-I were not mediated by increased FGF21 expression in protein malnutrition. Furthermore, FGF21 up-regulation rather appears to have a protective effect against obesity and hepatic steatosis in protein-malnourished animals.

  4. Hepatocyte growth factor reduces CXCL10 expression in keratinocytes.

    Science.gov (United States)

    Hisadome, Mitsuhiro; Ohnishi, Tomokazu; Kakimoto, Kyoko; Kusuyama, Joji; Bandow, Kenjiro; Kanekura, Takuro; Matsuguchi, Tetsuya

    2016-10-01

    Keratinocytes secrete vascular endothelial growth factor (VEGF) and angioregulatory chemokines during cutaneous wound healing. Hepatocyte growth factor (HGF) promotes skin re-epithelialization by increasing VEGF expression in keratinocytes. Here, we investigated the regulatory roles of HGF in the expression of genes encoding angiogenic and angiostatic chemokines in keratinocytes and found that HGF specifically inhibits mRNA expression of the angiostatic chemokine CXCL10 in both mouse primary keratinocytes and in the human keratinocyte cell line HaCaT through the MEK/ERK cascade. Furthermore, HGF inhibited tumor necrosis factor-α-induced CXCL10 expression at both mRNA and protein levels in HaCaT cells. Thus, HGF may orchestrate angiogenesis in wounded skin by modulating both VEGF and CXCL10 expression in keratinocytes. © 2016 Federation of European Biochemical Societies.

  5. Diameter limitation in growth of III-Sb-containing nanowire heterostructures.

    Science.gov (United States)

    Ek, Martin; Borg, B Mattias; Johansson, Jonas; Dick, Kimberly A

    2013-04-23

    The nanowire geometry offers significant advantages for exploiting the potential of III-Sb materials. Strain due to lattice mismatch is efficiently accommodated, and carrier confinement effects can be utilized in tunneling and quantum devices for which the III-Sb materials are of particular interest. It has however proven difficult to grow thin (below a few tens of nanometers), epitaxial III-Sb nanowires, as commonly no growth is observed below some critical diameter. Here we explore the processes limiting the diameter of III-Sb nanowires in a model system, in order to develop procedures to control this effect. The InAs-GaSb heterostructure system was chosen due to its great potential for tunneling devices in future low-power electronics. We find that with increasing growth temperature or precursor partial pressures, the critical diameter for GaSb growth on InAs decreases. To explain this trend we propose a model where the Gibbs-Thomson effect limits the Sb supersaturation in the catalyst particle. This understanding enabled us to further reduce the nanowire diameter down to 32 nm for GaSb grown on 21 nm InAs stems. Finally, we show that growth conditions must be carefully optimized for these small diameters, since radial growth increases for increased precursor partial pressures beyond the critical values required for nucleation.

  6. Complex responses of spring vegetation growth to climate in a moisture-limited alpine meadow.

    Science.gov (United States)

    Ganjurjav, Hasbagan; Gao, Qingzhu; Schwartz, Mark W; Zhu, Wenquan; Liang, Yan; Li, Yue; Wan, Yunfan; Cao, Xujuan; Williamson, Matthew A; Jiangcun, Wangzha; Guo, Hongbao; Lin, Erda

    2016-03-17

    Since 2000, the phenology has advanced in some years and at some locations on the Qinghai-Tibetan Plateau, whereas it has been delayed in others. To understand the variations in spring vegetation growth in response to climate, we conducted both regional and experimental studies on the central Qinghai-Tibetan Plateau. We used the normalized difference vegetation index to identify correlations between climate and phenological greening, and found that greening correlated negatively with winter-spring time precipitation, but not with temperature. We used open top chambers to induce warming in an alpine meadow ecosystem from 2012 to 2014. Our results showed that in the early growing season, plant growth (represented by the net ecosystem CO2 exchange, NEE) was lower in the warmed plots than in the control plots. Late-season plant growth increased with warming relative to that under control conditions. These data suggest that the response of plant growth to warming is complex and non-intuitive in this system. Our results are consistent with the hypothesis that moisture limitation increases in early spring as temperature increases. The effects of moisture limitation on plant growth with increasing temperatures will have important ramifications for grazers in this system.

  7. Explanatory factors of female entrepreneurship and limiting elements

    Directory of Open Access Journals (Sweden)

    Carmina Pérez-Pérez

    2016-06-01

    Full Text Available Researches on entrepreneurship from a gender perspective reveal significant differences not only between the levels of participation of men and women in business, but also between the orientations, motives and business opportunities for both. Based on this fact, the following investigation is performed, whose objective is twofold: firstly, to know what are the aspects that influence the entrepreneurship of women and secondly, to identify what factors determine and/or difficult the creation and development of business that they undertake. To achieve both, it is reviewed, first, the literature on this subject and, second, are exposed the main results of the qualitative analysis with Atlas.ti from interviews with a group of Spanish entrepreneurs.

  8. The importance of neuronal growth factors in the ovary.

    Science.gov (United States)

    Streiter, S; Fisch, B; Sabbah, B; Ao, A; Abir, R

    2016-01-01

    The neurotrophin family consists of nerve growth factor (NGF), neurotrophin 3 (NT3) and neurotrophin 4/5 (NT4/5), in addition to brain-derived neurotrophic factor (BDNF) and the neuronal growth factors, glial cell line-derived neurotrophic factor (GDNF) and vasointestinal peptide (VIP). Although there are a few literature reviews, mainly of animal studies, on the importance of neurotrophins in the ovary, we aimed to provide a complete review of neurotrophins as well as neuronal growth factors and their important roles in normal and pathological processes in the ovary. Follicular assembly is probably stimulated by complementary effects of NGF, NT4/5 and BDNF and their receptors. The neurotrophins, GDNF and VIP and their receptors have all been identified in preantral and antral follicles of mammalian species, including humans. Transgenic mice with mutations in the genes encoding for Ngf, Nt4/5 and Bdnf and their tropomyosin-related kinase β receptor showed a reduction in preantral follicles and an abnormal ovarian morphology, whereas NGF, NT3, GDNF and VIP increased the in vitro activation of primordial follicles in rats and goats. Additionally, NGF, NT3 and GDNF promoted follicular cell proliferation; NGF, BDNF and VIP were shown to be involved in ovulation; VIP inhibited follicular apoptosis; NT4/5, BDNF and GDNF promoted oocyte maturation and NGF, NT3 and VIP stimulated steroidogenesis. NGF may also exert a stimulatory effect in ovarian cancer and polycystic ovarian syndrome (PCOS). Low levels of NGF and BDNF in follicular fluid may be associated with diminished ovarian reserve and high levels with endometriosis. More knowledge of the roles of neuronal growth factors in the ovary has important implications for the development of new therapeutic drugs (such as anti-NGF agents) for ovarian cancer and PCOS as well as various infertility problems, warranting further research.

  9. Human epidermal growth factor and the proliferation of human fibroblasts.

    Science.gov (United States)

    Carpenter, G; Cohen, S

    1976-06-01

    The effect of human epidermal growth factor (hEGF), a 5,400 molecular weight polypeptide isolated from human urine, on the growth of human foreskin fibroblasts (HF cells) was studied by measuring cell numbers and the incorporation of labeled thymidine. The addition of hEGF to HF cells growing in a medium containing 10% calf serum resulted in a 4-fold increase in the final density. The presence of hEGF also promoted the growth of HF cells in media containing either 1% calf serum or 10% gamma globulin-free serum. The addition of hEGF to quiescent confluent monolayers of HF cells, maintained in a medium with 1% calf serum for 48 hours, resulted in a 10- to 20-fold increase in the amount of 3H-thymidine incorporation after 20-24 hours. The stimulation of thymidine incorporation was maximal at an hEGF concentration of 2 ng/ml, was dependent on the presence of serum, and was enhanced by the addition of ascorbic acid. In confluent cultures of HF cells, subject to density dependent inhibition of growth, hEGF was able to stimulate DNA synthesis more effectively than fresh calf serum. Human EGF stimulated DNA synthesis in quiescent cultures, however, regardless of cell density. The addition of rabbit anti-hEGF inhibited all effects of this growth factor on HF cells.

  10. Phosphorus as a limiting factor on sustainable greywater irrigation.

    Science.gov (United States)

    Turner, Ryan D R; Will, Geoffrey D; Dawes, Les A; Gardner, Edward A; Lyons, David J

    2013-07-01

    Water reuse through greywater irrigation has been adopted worldwide and has been proposed as a potential sustainable solution to increased water demands. Despite widespread adoption, there is limited domestic knowledge of greywater reuse. There is no pressure to produce low-level phosphorus products and current guidelines and legislation, such as those in Australia, may be inadequate due to the lack of long-term data to provide a sound scientific basis. Research has clearly identified phosphorus as a potential environmental risk to waterways from many forms of irrigation. To assess the sustainability of greywater irrigation, this study compared four residential lots that had been irrigated with greywater for four years and adjacent non-irrigated lots that acted as controls. Each lot was monitored for the volume of greywater applied and selected physic-chemical water quality parameters and soil chemistry profiles were analysed. The non-irrigated soil profiles showed low levels of phosphorus and were used as controls. The Mechlich3 Phosphorus ratio (M3PSR) and Phosphate Environmental Risk Index (PERI) were used to determine the environmental risk of phosphorus leaching from the irrigated soils. Soil phosphorus concentrations were compared to theoretical greywater irrigation loadings. The measured phosphorus soil concentrations and the estimated greywater loadings were of similar magnitude. Sustainable greywater reuse is possible; however incorrect use and/or lack of understanding of how household products affect greywater can result in phosphorus posing a significant risk to the environment.

  11. Potential and limitation of combining terrestrial and marine growth records from Iceland

    Science.gov (United States)

    Piermattei, A.; Urbinati, C.; Tonelli, E.; Eggertsson, Ó.; Levanič, T.; Kaczka, R. J.; Andrew, C.; Schöne, B. R.; Büntgen, U.

    2017-08-01

    Seasonally formed, perennial growth increments of various organisms may possibly contain information about past environmental changes, well before instrumental measurements occurred. Such annually resolved proxy records have been mainly obtained from terrestrial archives, with a paucity of similar data originating from marine habitats. Iceland represents ideal conditions to develop both, tree ring (dendro) and bivalve shell (sclero) chronologies from adjacent sites. Here we introduce the first network of Icelandic birch (Betula pubescens Ehrh.) and rowan (Sorbus aucuparia) dendrochronologies, as well as ocean quahog (Arctica islandica L.) sclerochronologies. In order to identify the dominant external drivers of tree and shell growth, we assess the common growth trends and growth extremes within and between the terrestrial and marine records, as well as relationships of both archives with instrumental-based meteorological indices. Capturing a strong signal of June-August mean air temperature, the dendrochronologies are significantly positively correlated to each other. The sclerochronologies, however, reveal much lower growth coherency, which likely results from different sampling strategies and growth habitats. Disagreement between the dendro- and sclerochronologies possibly originates from unequal sample size, offset in the seasonal timing and rate of the growth, as well as varying sensitivities to different environmental factors. Our results emphasize the importance of considering a wide range of species and taxa to reconstruct a more complete picture of terrestrial and marine ecosystem functioning and productivity across various spatiotemporal scales.

  12. Metabolite profiling uncovers plasmid-induced cobalt limitation under methylotrophic growth conditions.

    Directory of Open Access Journals (Sweden)

    Patrick Kiefer

    Full Text Available BACKGROUND: The introduction and maintenance of plasmids in cells is often associated with a reduction of growth rate. The reason for this growth reduction is unclear in many cases. METHODOLOGY/PRINCIPAL FINDINGS: We observed a surprisingly large reduction in growth rate of about 50% of Methylobacterium extorquens AM1 during methylotrophic growth in the presence of a plasmid, pCM80 expressing the tetA gene, relative to the wild-type. A less pronounced growth delay during growth under non-methylotrophic growth conditions was observed; this suggested an inhibition of one-carbon metabolism rather than a general growth inhibition or metabolic burden. Metabolome analyses revealed an increase in pool sizes of ethylmalonyl-CoA and methylmalonyl-CoA of more than 6- and 35-fold, respectively, relative to wild type, suggesting a strongly reduced conversion of these central intermediates, which are essential for glyoxylate regeneration in this model methylotroph. Similar results were found for M. extorquens AM1 pCM160 which confers kanamycin resistance. These intermediates of the ethylmalonyl-CoA pathway have in common their conversion by coenzyme B(12-dependent mutases, which have cobalt as a central ligand. The one-carbon metabolism-related growth delay was restored by providing higher cobalt concentrations, by heterologous expression of isocitrate lyase as an alternative path for glyoxylate regeneration, or by identification and overproduction of proteins involved in cobalt import. CONCLUSIONS/SIGNIFICANCE: This study demonstrates that the introduction of the plasmids leads to an apparent inhibition of the cobalt-dependent enzymes of the ethylmalonyl-CoA pathway. Possible explanations are presented and point to a limited cobalt concentration in the cell as a consequence of the antibiotic stress.

  13. Surface proteome analysis identifies platelet derived growth factor receptor-alpha as a critical mediator of transforming growth factor-beta-induced collagen secretion.

    Science.gov (United States)

    Heinzelmann, Katharina; Noskovičová, Nina; Merl-Pham, Juliane; Preissler, Gerhard; Winter, Hauke; Lindner, Michael; Hatz, Rudolf; Hauck, Stefanie M; Behr, Jürgen; Eickelberg, Oliver

    2016-05-01

    Fibroblasts are extracellular matrix-producing cells in the lung. Fibroblast activation by transforming growth factor-beta leads to myofibroblast-differentiation and increased extracellular matrix deposition, a hallmark of pulmonary fibrosis. While fibroblast function with respect to migration, invasion, and extracellular matrix deposition has been well-explored, little is known about the surface proteome of lung fibroblasts in general and its specific response to fibrogenic growth factors, in particular transforming growth factor-beta. We thus performed a cell-surface proteome analysis of primary human lung fibroblasts in presence/absence of transforming growth factor-beta, followed by characterization of our findings using FACS analysis, Western blot, and siRNA-mediated knockdown experiments. We identified 213 surface proteins significantly regulated by transforming growth factor-beta, platelet derived growth factor receptor-alpha being one of the top down-regulated proteins. Transforming growth factor beta-induced downregulation of platelet derived growth factor receptor-alpha induced upregulation of platelet derived growth factor receptor-beta expression and phosphorylation of Akt, a downstream target of platelet derived growth factor signaling. Importantly, collagen type V expression and secretion was strongly increased after forced knockdown of platelet derived growth factor receptor-alpha, an effect that was potentiated by transforming growth factor-beta. We therefore show previously underappreciated cross-talk of transforming growth factor-beta and platelet derived growth factor signaling in human lung fibroblasts, resulting in increased extracellular matrix deposition in a platelet derived growth factor receptor-alpha dependent manner. These findings are of particular importance for the treatment of lung fibrosis patients with high pulmonary transforming growth factor-beta activity.

  14. Potential role of growth factors with particular focus on growth hormone and insulin-like growth factor-1 in the management of chronic kidney disease

    DEFF Research Database (Denmark)

    Feldt-Rasmussen, B.; M., El Nahas

    2009-01-01

    Prevention and treatment of chronic kidney disease (CKD) so far primarily has been based on early and aggressive treatment of hypertension. A number of other therapeutic approaches have the potential of being translated to the clinical area within the foreseeable future. In this review, we focus...... on growth factors and, in particular, on the role of growth hormone (GH) and insulin-like growth factor-1 (IGF-1) in the treatment of CKD and the management of its complications. Disturbances of the GH-IGF-1 axis in CKD have suggested therapeutic roles for both the inhibition, as well as the stimulation...

  15. Inositol-Limited Growth, Repair, and Translocation in an Inositol-Requiring Mutant of Neurospora crassa

    OpenAIRE

    Hanson, Barbara A.

    1980-01-01

    The biochemical consequences of inositol limitation in an inositol auxotroph of Neurospora crassa have been examined as a means of disclosing the cellular role of inositol. The cellular levels of inositol in the inl mutant were proportional to the concentration of inositol in the growth medium whereas inositol phosphate levels remained relatively constant at about 0.1 μmol/g (dry weight). After 72 h of growth, about 57-fold more protein per milligram (dry weight) was released by the mutant gr...

  16. Connective tissue growth factor and vascular endothelial growth factor from airway smooth muscle interact with the extracellular matrix

    NARCIS (Netherlands)

    Burgess, Janette K; Ge, Qi; Poniris, Maree H; Boustany, Sarah; Twigg, Stephen M; Black, Judith L; Johnson, Peter R A

    2006-01-01

    Airway remodeling describes the structural changes that occur in the asthmatic airway that include airway smooth muscle hyperplasia, increases in vascularity due to angiogenesis, and thickening of the basement membrane. Our aim in this study was to examine the effect of transforming growth factor-be

  17. Transforming growth factor (TGF)-. alpha. in human milk

    Energy Technology Data Exchange (ETDEWEB)

    Okada, Masaki; Wakai, Kae; Shizume, Kazuo (Research Institute for Growth Sciences, Tokyo (Japan)); Iwashita, Mitsutoshi (Tokyo Women' s Medical College (Japan)); Ohmura, Eiji; Kamiya, Yoshinobu; Murakami, Hitomi; Onoda, Noritaka; Tsushima, Toshio

    1991-01-01

    Transforming growth factor (TGF)-{alpha} and epidermal growth factor (EGF) were measured in human milk by means of homologous radioimmunoassay. As previously reported, EGF concentration in the colostrum was approximately 200 ng/ml and decreased to 50 ng/ml by day 7 postpartum. The value of immunoreactive (IR)-TGF-{alpha} was 2.2-7.2 ng/ml, much lower than that of EGF. In contrast to EGF, the concentration of IR-TGF-{alpha} was fairly stable during the 7 postpartum days. There was no relationship between the concentrations of IR-TGF-{alpha} and IR-EGF, suggesting that the regulatory mechanism in the release of the two growth factors is different. On gel-chromatography using a Sephadex G-50 column, IR-EGF appeared in the fraction corresponding to that of authentic human EGF, while 70%-80% of the IR-TGF-{alpha} was eluted as a species with a molecular weight greater than that of authentic human TGF-{alpha}. Although the physiological role of TGF-{alpha} in milk is not known, it is possible that it is involved in the development of the mammary gland and/or the growth of newborn infants.

  18. Thrombopoietin is a growth factor for rat hepatic progenitors.

    Science.gov (United States)

    Schmelzer, Eva; Deiwick, Andrea; Bruns, Helge; Fiegel, Henning C; Bader, Augustinus

    2008-03-01

    The liver is the primary site of hematopoiesis during fetal development; it has been shown that thrombopoietin (TPO) produced by the liver during fetal development is a major regulator of megakaryocytopoiesis. As maximum liver growth and hematopoiesis occur simultaneously, we hypothesized that TPO may act as a growth factor for hepatic progenitors. Therefore, the influence of TPO on the proliferation of fetal hepatic progenitors in vitro compared with that of adult hepatocytes was analyzed. The expression of the TPO receptor, c-mpl, was investigated in fetal and adult liver. Cell proliferation was measured by bromodeoxyuridine incorporation and total cell counts. TPO and c-mpl gene expression was investigated by reverse transcription polymerase chain reaction. The cell surface expression of c-mpl was analyzed in fetal and adult human liver by immunohistochemistry. Hepatic progenitors of fetal and adult liver but not hepatocytes expressed the TPO receptor, c-mpl, on the cell surface. Fetal hepatic progenitors expressed mRNA for TPO and its receptor. TPO stimulated cell proliferation and increased cell numbers of cultured rat fetal hepatic progenitors but not adult hepatocytes. We conclude that TPO acts in addition to its known role in megakaryocytopoiesis as a growth factor for hepatic progenitors but not hepatocytes in vitro; thus, TPO represents a growth factor for hepatic progenitors during fetal liver development.

  19. FGF19 functions as autocrine growth factor for hepatoblastoma.

    Science.gov (United States)

    Elzi, David J; Song, Meihua; Blackman, Barron; Weintraub, Susan T; López-Terrada, Dolores; Chen, Yidong; Tomlinson, Gail E; Shiio, Yuzuru

    2016-03-01

    Hepatoblastoma is the most common liver cancer in children, accounting for over 65% of all childhood liver malignancies. Hepatoblastoma is distinct from adult liver cancer in that it is not associated with hepatitis virus infection, cirrhosis, or other underlying liver pathology. The paucity of appropriate cell and animal models has been hampering the mechanistic understanding of hepatoblastoma pathogenesis. Consequently, there is no molecularly targeted therapy for hepatoblastoma. To gain insight into cytokine signaling in hepatoblastoma, we employed mass spectrometry to analyze the proteins secreted from Hep293TT hepatoblastoma cell line we established and identified the specific secretion of fibroblast growth factor 19 (FGF19), a growth factor for liver cells. We determined that silencing FGF19 by shRNAs or neutralizing secreted FGF19 by anti-FGF19 antibody inhibits the proliferation of hepatoblastoma cells. Furthermore, blocking FGF19 signaling by an FGF receptor kinase inhibitor suppressed hepatoblastoma growth. RNA expression analysis in hepatoblastoma tumors revealed that the high expression of FGF19 signaling pathway components as well as the low expression of FGF19 signaling repression targets correlates with the aggressiveness of the tumors. These results suggest the role of FGF19 as autocrine growth factor for hepatoblastoma.

  20. Very-high-growth-factor Planar Ablative Rayleigh Taylor Experiments

    Energy Technology Data Exchange (ETDEWEB)

    Bradley, D K; Braun, D G; Glendinning, S G; Edwards, M J; Milovich, J L; Sorce, C M; Collins, G W; Haan, S W; Page, R H

    2006-10-30

    The Rayleigh-Taylor (RT) instability is an important factor in bounding the performance envelope of ignition targets. This paper describes an experiment for ablative RT instability that for the first time achieves growth factors close to those expected to occur in ignition targets at the National Ignition Facility (NIF). The large growth allows small seed perturbations to be detected and can be used to place an upper bound on perturbation growth at the ablation front resulting from microstructure in the preferred Be ablator. The experiments were performed on the Omega laser using a halfraum 1.2 mm long by 2 mm diameter with a 75% laser entrance hole. The halfraum was filled with {approx} 1 atm of neopentane to delay gold plasma from closing the diagnostic line of sight down the axis of the halfraum. The ablator was mounted at the base of the halfraum, and was accelerated by a two stepped X-ray pulse consisting of an early time section {approx} 100 eV to emulate the NIF foot followed by an approximately constant {approx} 150 eV drive sustained over an additional 5-7ns. It is this long pulse duration and late time observation that distinguishes the present work from previous experiments, and is responsible for the large growth that is achieved. The growth of a 2D sinusoidal perturbation machined on the drive side of the ablator was measured using face-on radiography. The diagnostic view remained open until {approx} 11 ns with maximum growth factors measured to be {approx} 200. The trajectory of the ablator was measured using streaked backlit radiography. The design and analysis of the experiments is described, and implications for experiments on ignition target ablators are discussed.

  1. Growth Factor Liberation and DPSC Response Following Dentine Conditioning.

    Science.gov (United States)

    Sadaghiani, L; Gleeson, H B; Youde, S; Waddington, R J; Lynch, C D; Sloan, A J

    2016-10-01

    Liberation of the sequestrated bioactive molecules from dentine by the action of applied dental materials has been proposed as an important mechanism in inducing a dentinogenic response in teeth with viable pulps. Although adhesive restorations and dentine-bonding procedures are routinely practiced, clinical protocols to improve pulp protection and dentine regeneration are not currently driven by biological knowledge. This study investigated the effect of dentine (powder and slice) conditioning by etchants/conditioners relevant to adhesive restorative systems on growth factor solubilization and odontoblast-like cell differentiation of human dental pulp progenitor cells (DPSCs). The agents included ethylenediaminetetraacetic acid (EDTA; 10%, pH 7.2), phosphoric acid (37%, pH EDTA, phosphoric acid, and citric acid from powdered dentine. The dentine matrix extracts were shown to be bioactive, capable of stimulating odontogenic/osteogenic differentiation as observed by gene expression and phenotypic changes in DPSCs cultured in monolayer on plastic. Polyacrylic acid failed to solubilize proteins from powdered dentine and was therefore considered ineffective in triggering a growth factor-mediated response in cells. The study went on to investigate the effect of conditioning dentine slices on growth factor liberation and DPSC behavior. Conditioning by EDTA, phosphoric acid, and citric acid exposed growth factors on dentine and triggered an upregulation in genes associated with mineralized differentiation, osteopontin, and alkaline phosphatase in DPSCs cultured on dentine. The cells demonstrated odontoblast-like appearances with elongated bodies and long extracellular processes extending on dentine surface. However, phosphoric acid-treated dentine appeared strikingly less populated with cells, suggesting a detrimental impact on cell attachment and growth when conditioning by this agent. These findings take crucial steps in informing clinical practice on dentine

  2. Steady Impact Factor Growth for MDPI Open Access Journals

    Directory of Open Access Journals (Sweden)

    Alexander Thiesen

    2012-09-01

    Full Text Available For the past three years MDPI has announced the newly released impact factors for its Open Access journals by the means of an annual editorial [1–3]. In 2012 we are—once again—pleased to report that the growth of the impact factors of MDPI’s Open Access journals continues. This year’s edition of the Journal Citation Reports (JCR, which is published annually by Thomson Reuters, includes 10 journals published by MDPI, including three that have received their first official Impact Factors—International Journal of Environmental Research and Public Health (IJERPH, Materials and Nutrients. Table 1 reports the latest Impact Factors for 2011. Figure 1 graphically depicts the evolution of the Impact Factors for four MDPI open access journals that have received Impact Factors in the past. Table 2 reports the ranking of the MDPI journals within the subject categories of the Science Citation Index Expanded (SCIE.

  3. GH responses to growth hormone releasing factor in depression.

    Science.gov (United States)

    Thomas, R; Beer, R; Harris, B; John, R; Scanlon, M

    1989-01-01

    The growth hormone (GH), thyrotrophin (TSH) and prolactin response to growth hormone releasing factor (GRF) was investigated in 18 patients suffering from major depression with melancholia and in 18 age- and sex-matched normal controls. There was no significant difference in the GH response to GRF stimulation between the patients and controls and in neither subject group was there a demonstrable TSH or prolactin response to GRF. These findings indicate that the pathophysiology underlying the blunted GH response to pharmacological challenge, demonstrated in other studies, must lie at a suprapituitary level.

  4. Muscle growth in young horses: Effects of age, cytokines, and growth factors.

    Science.gov (United States)

    LaVigne, E K; Jones, A K; Londoño, A Sanchez; Schauer, A S; Patterson, D F; Nadeau, J A; Reed, S A

    2015-12-01

    Success as equine athletes requires proper muscle growth in young horses. Muscle hypertrophy occurs through protein synthesis and the contribution of muscle satellite cells, which can be stimulated or inhibited by cytokines and growth factors present during exercise and growth. The hypotheses of this study were that 1) the LM area in young horses would increase over 1 yr, and 2) specific cytokines and growth factors (IL-1β, IL-6, tumor necrosis factor [TNF]-α, IGF-I, and fibroblast growth factor [FGF]-2) would alter proliferation and differentiation of satellite cells isolated from young horses. Fourteen horses were divided into 3 age groups: weanlings ( = 5), yearlings to 2 yr olds ( = 4), and 3 to 4 yr olds ( = 5). The area, height, and subcutaneous fat depth of the LM were measured using ultrasonography, and BW and BCS were taken in October (Fall1), April (Spring), and October of the following year (Fall2). Satellite cells obtained from 10-d-old foals ( = 4) were cultured in the presence of IL-6, IL-1β, TNF-α, IGF-I, or FGF-2 before evaluation of proliferation and differentiation. Data were analyzed using PROC MIXED in SAS. Body weight increased from Fall1 to Spring in weanlings ( 0.61). There was a significant increase in LM area in all animals from Spring to Fall2 ( growth occurring in summer. By stimulating or inhibiting proliferation and differentiation of satellite cells, IL-6, TNF-α, IL-1β, IGF-I, and FGF-2 may alter muscle growth in young horses, thereby impacting athletic potential.

  5. Efficiency limit factor analysis for the Francis-99 hydraulic turbine

    Science.gov (United States)

    Zeng, Y.; Zhang, L. X.; Guo, J. P.; Guo, Y. K.; Pan, Q. L.; Qian, J.

    2017-01-01

    The energy loss in hydraulic turbine is the most direct factor that affects the efficiency of the hydraulic turbine. Based on the analysis theory of inner energy loss of hydraulic turbine, combining the measurement data of the Francis-99, this paper calculates characteristic parameters of inner energy loss of the hydraulic turbine, and establishes the calculation model of the hydraulic turbine power. Taken the start-up test conditions given by Francis-99 as case, characteristics of the inner energy of the hydraulic turbine in transient and transformation law are researched. Further, analyzing mechanical friction in hydraulic turbine, we think that main ingredients of mechanical friction loss is the rotation friction loss between rotating runner and water body, and defined as the inner mechanical friction loss. The calculation method of the inner mechanical friction loss is given roughly. Our purpose is that explore and research the method and way increasing transformation efficiency of water flow by means of analysis energy losses in hydraulic turbine.

  6. A risk modelling approach for setting microbiological limits using enterococci as indicator for growth potential of Salmonella in pork.

    Science.gov (United States)

    Bollerslev, Anne Mette; Nauta, Maarten; Hansen, Tina Beck; Aabo, Søren

    2017-01-02

    Microbiological limits are widely used in food processing as an aid to reduce the exposure to hazardous microorganisms for the consumers. However, in pork, the prevalence and concentrations of Salmonella are generally low and microbiological limits are not considered an efficient tool to support hygiene interventions. The objective of the present study was to develop an approach which could make it possible to define potential risk-based microbiological limits for an indicator, enterococci, in order to evaluate the risk from potential growth of Salmonella. A positive correlation between the concentration of enterococci and the prevalence and concentration of Salmonella was shown for 6640 pork samples taken at Danish cutting plants and retail butchers. The samples were collected in five different studies in 2001, 2002, 2010, 2011 and 2013. The observations that both Salmonella and enterococci are carried in the intestinal tract, contaminate pork by the same mechanisms and share similar growth characteristics (lag phase and maximum specific growth rate) at temperatures around 5-10°C, suggest a potential of enterococci to be used as an indicator of potential growth of Salmonella in pork. Elevated temperatures during processing will lead to growth of both enterococci and, if present, also Salmonella. By combining the correlation between enterococci and Salmonella with risk modelling, it is possible to predict the risk of salmonellosis based on the level of enterococci. The risk model used for this purpose includes the dose-response relationship for Salmonella and a reduction factor to account for preparation of the fresh pork. By use of the risk model, it was estimated that the majority of salmonellosis cases, caused by the consumption of pork in Denmark, is caused by the small fraction of pork products that has enterococci concentrations above 5logCFU/g. This illustrates that our approach can be used to evaluate the potential effect of different microbiological

  7. Intragraft platelet-derived growth factor-alpha and transforming growth factor-beta1 during the development of accelerated graft vascular disease after clinical heart transplantation

    NARCIS (Netherlands)

    de Groot-Kruseman, H A; Baan, C C; Mol, W M; Niesters, H G; Maat, A P; Balk, A H; Weimar, W

    1999-01-01

    This study was to determine whether the growth factors platelet-derived growth factor-alpha (PDGF-alpha) and transforming growth factor-beta1 (TGF-beta1) contribute to the development of graft vascular disease (GVD) after clinical heart transplantation. We analysed intragraft PDGF-alpha and TGF-beta

  8. Limitations in direct and indirect methods for solving optimal control problems in growth theory

    Directory of Open Access Journals (Sweden)

    Ratković Kruna

    2016-01-01

    Full Text Available The focus of this paper is on a comprehensive analysis of different methods and mathematical techniques used for solving optimal control problems (OCP in growth theory. Most important methods for solving dynamic non-linear infinite-horizon growth models using optimal control theory are presented and a critical view of the limitations of different methods is given. The main problem is to determine the optimal rate of growth over time in a way that maximizes the welfare function over an infinite horizon. The welfare function depends on capital-labor ratio, the state variable, and the per-capita consumption, the control variable. Numerical methods for solving OCP are divided into two classes: direct and indirect approach. How the indirect approach can be used is given in the example of the neo-classical growth model. In order to present the indirect and the direct approach simultaneously, two endogenous growth models, one written by Romer and another by Lucas and Uzawa, are studied. Advantages and efficiency of these different approaches will be discussed. Although the indirect methods for solving OCP are still the most expanded in growth theory, it will be seen that using direct methods can also be very efficient and help to overcome problems that can occur by using the indirect approach.

  9. Natural resources as a factor of economic growth in Kosovo

    Directory of Open Access Journals (Sweden)

    Haki Shatri

    2015-11-01

    Full Text Available In the history of the economic growth, there are numerous examples of countries that have developed based on their available natural resources. Especially, these assets have been the propulsion of the development in the initial period. But we also find some cases where countries with limited natural resources have experienced dynamic economic development. Kosovo is the last federal unit dismembered from former Yugoslavia after a decade under Milosevic’s Serbian regime and a two years’ war. International intervention and the inclusion of the country under an international protectorate created the conditions for the development of devastated economy by war and the robbery to be recovered together with the creation of institutional and economic infrastructure (Lidhja e Ekonomistëve të Kosovës, 1996. Under these conditions, everything had to start from scratch. The only development factor that Kosovo possessed was the human factor - age structure and the abundant natural resources, especially in key sectors such as the energy and in mining and minerals, agriculture and tourism. Thus it is sustainable the conclusion that “The rapid and sustainable economic and social development of Kosovo depends substantially from the implementation of the appropriate policies and suitable economic reforms that enable more rational use of its natural and human resources”. The list of the available resources of Kosovo is long. Kosovo possesses significant amount of all mineral raw materials in both quality and quantity terms. Among the most important raw materials have been ranked the power-lignite mining that is stretched into three basins and it is estimated to be around 9 billion exploitable tons (Kelmendi, 2012. Kosovo also owns mineral resources which are found in the Trepca’s Metals basin. The geological researches show favorable conditions of exploitation and high quality of the ore. Mainly one can found the lead, zinc, silver and other

  10. Maternal serum placental growth hormone, but not human placental lactogen or insulin growth factor-1, is positively associated with fetal growth in the first half of pregnancy

    DEFF Research Database (Denmark)

    Pedersen, N G; Juul, A; Christiansen, M

    2010-01-01

    To investigate if maternal levels of human placental lactogen (hPL), placental growth hormone (PGH) and insulin-like growth factor-1 (IGF-1) are associated with growth rate of the biparietal diameter (BPD) in the first half of pregnancy.......To investigate if maternal levels of human placental lactogen (hPL), placental growth hormone (PGH) and insulin-like growth factor-1 (IGF-1) are associated with growth rate of the biparietal diameter (BPD) in the first half of pregnancy....

  11. Growth factor choice is critical for successful functionalization of nanoparticles

    Directory of Open Access Journals (Sweden)

    Josephine ePinkernelle

    2015-09-01

    Full Text Available Nanoparticles (NPs show new characteristics compared to the corresponding bulk material. These nanoscale properties make them interesting for various applications in biomedicine and life sciences. One field of application is the use of magnetic NPs to support regeneration in the nervous system. Drug delivery requires a functionalization of NPs with bio-functional molecules. In our study, we functionalized self-made PEI-coated iron oxide NPs with nerve growth factor (NGF and glial cell-line derived neurotrophic factor (GDNF. Next, we tested the bio-functionality of NGF in a rat pheochromocytoma cell line (PC12 and the bio-functionality of GDNF in an organotypic spinal cord culture. Covalent binding of NGF to PEI-NPs impaired bio-functionality of NGF, but non-covalent approach differentiated PC12 cells reliably. Non-covalent binding of GDNF showed a satisfying bio-functionality of GDNF:PEI-NPs, but turned out to be instable in conjugation to the PEI-NPs. Taken together, our study showed the importance of assessing bio-functionality and binding stability of functionalized growth factors using proper biological models. It also shows that successful functionalization of magnetic NPs with growth factors is dependent on the used binding chemistry and that it is hardly predictable. For use as therapeutics, functionalization strategies have to be reproducible and future studies are needed.

  12. Nutrition, insulin, insulin-like growth factors and cancer.

    Science.gov (United States)

    Giovannucci, E

    2003-01-01

    The incidence of colon, pancreatic, and kidney cancers, as well as aggressive prostate cancer in men, and breast and endometrial cancer in women is invariably high in Western countries. Nutritional and related factors have been typically implicated. This review presents a model integrating nutrition, insulin and IGF-1 physiology ("bioactive" IGF-1), and carcinogenesis based on the following: (1) insulin and the IGF-1 axis function in an integrated fashion to promote cell growth and survival; (2) chronic exposure to these growth properties enhances carcinogenesis; (3) factors that influence bioactive IGF-1 will affect cancer risk. The model presented here summarizes the data that chronic exposure to high levels of insulin and IGF-1 may mediate many of the risk factors for some cancers that are high in Western populations. This hypothesis may help explain some of the epidemiologic patterns observed for these cancers, both from a cross-national perspective and within populations. Of particular importance is that some of relevant factors are modifiable through nutritional and lifestyle interventions. Out of a variety of perspectives presented, nutritional manipulation through the insulin pathway may be more feasible than attempting to influence total IGF-1 concentrations, which are determined largely by growth hormone. Further study is required to test these conclusions.

  13. Bioregulation of lubricin expression by growth factors and cytokines

    Directory of Open Access Journals (Sweden)

    A R C Jones

    2007-03-01

    Full Text Available Lubricin, also commonly referred to as superficial zone protein (SZP and proteoglycan 4 (PRG4, is a multifaceted, cytoprotective glycoprotein that contributes to the boundary lubrication properties facilitating low friction levels at interfacing surfaces of articular cartilage. Biological processes effecting the gain or loss of lubricin function may therefore have important consequences relevant to joint physiology and pathology. Herein, we describe experiments conducted to extend our understanding of the influence of various cytokines and growth factors on lubricin gene expression and protein secretion in synovial tissues. Exposure of synoviocytes, chondrocytes and cartilage explants to proinflammatory cytokines such as interleukin-1 (IL-1 and tumor necrosis factor-alpha (TNF-alpha results in a marked reduction in the expression and/or abundance of secreted lubricin, with corresponding alterations in the amounts of cartilage-associated (boundary lubricin. Conversely, treatment with transforming growth factor-beta (TGF-beta significantly upregulates lubricin synthesis, secretion and cartilage boundary association. Oncostatin M also appears to be capable of modulating lubricin metabolism, with the potential to induce lubricin synthesis by chondrocytes. Collectively, the results of studies on cytokine and growth factor regulation of lubricin biosynthesis and biodistribution may help provide new insights and therapeutic perspectives for promoting joint function.

  14. Nitrogen limitation of growth and nutrient dynamics in a disturbed mangrove forest, Indian River Lagoon, Florida

    Science.gov (United States)

    Feller, Ilka C.; Whigham, D.F.; McKee, K.L.; Lovelock, C.E.

    2003-01-01

    The objectives of this study were to determine effects of nutrient enrichment on plant growth, nutrient dynamics, and photosynthesis in a disturbed mangrove forest in an abandoned mosquito impoundment in Florida. Impounding altered the hydrology and soil chemistry of the site. In 1997, we established a factorial experiment along a tree-height gradient with three zones, i.e., fringe, transition, dwarf, and three fertilizer treatment levels, i.e., nitrogen (N), phosphorus (P), control, in Mosquito Impoundment 23 on the eastern side of Indian River. Transects traversed the forest perpendicular to the shoreline, from a Rhizophora mangle-dominated fringe through an Avicennia germinans stand of intermediate height, and into a scrub or dwarf stand of A. germinans in the hinterland. Growth rates increased significantly in response to N fertilization. Our growth data indicated that this site is N-limited along the tree-height gradient. After 2 years of N addition, dwarf trees resembled vigorously growing saplings. Addition of N also affected internal dynamics of N and P and caused increases in rates of photosynthesis. These findings contrast with results for a R. mangle-dominated forest in Belize where the fringe is N-limited, but the dwarf zone is P-limited and the transition zone is co-limited by N and P. This study demonstrated that patterns of nutrient limitation in mangrove ecosystems are complex, that not all processes respond similarly to the same nutrient, and that similar habitats are not limited by the same nutrient when different mangrove forests are compared.

  15. Growth hormone, the insulin-like growth factor axis, insulin and cancer risk.

    Science.gov (United States)

    Clayton, Peter E; Banerjee, Indraneel; Murray, Philip G; Renehan, Andrew G

    2011-01-01

    Growth hormone (GH), insulin-like growth factor (IGF)-I and insulin have potent growth-promoting and anabolic actions. Their potential involvement in tumor promotion and progression has been of concern for several decades. The evidence that GH, IGF-I and insulin can promote and contribute to cancer progression comes from various sources, including transgenic and knockout mouse models and animal and human cell lines derived from cancers. Assessments of the GH-IGF axis in healthy individuals followed up to assess cancer incidence provide direct evidence of this risk; raised IGF-I levels in blood are associated with a slightly increased risk of some cancers. Studies of human diseases characterized by excess growth factor secretion or treated with growth factors have produced reassuring data, with no notable increases in de novo cancers in children treated with GH. Although follow-up for the vast majority of these children does not yet extend beyond young adulthood, a slight increase in cancers in those with long-standing excess GH secretion (as seen in patients with acromegaly) and no overall increase in cancer with insulin treatment, have been observed. Nevertheless, long-term surveillance for cancer incidence in all populations exposed to increased levels of GH is vitally important.

  16. Myoferlin is required for insulin-like growth factor response and muscle growth.

    Science.gov (United States)

    Demonbreun, Alexis R; Posey, Avery D; Heretis, Konstantina; Swaggart, Kayleigh A; Earley, Judy U; Pytel, Peter; McNally, Elizabeth M

    2010-04-01

    Insulin-like growth factor (IGF) is a potent stimulus of muscle growth. Myoferlin is a membrane-associated protein important for muscle development and regeneration. Myoferlin-null mice have smaller muscles and defective myoblast fusion. To understand the mechanism by which myoferlin loss retards muscle growth, we found that myoferlin-null muscle does not respond to IGF1. In vivo after IGF1 infusion, control muscle increased myofiber diameter by 25%, but myoferlin-null muscle was unresponsive. Myoblasts cultured from myoferlin-null muscle and treated with IGF1 also failed to show the expected increase in fusion to multinucleate myotubes. The IGF1 receptor colocalized with myoferlin at sites of myoblast fusion. The lack of IGF1 responsiveness in myoferlin-null myoblasts was linked directly to IGF1 receptor mistrafficking as well as decreased IGF1 signaling. In myoferlin-null myoblasts, the IGF1 receptor accumulated into large vesicular structures. These vesicles colocalized with a marker of late endosomes/lysosomes, LAMP2, specifying redirection from a recycling to a degradative pathway. Furthermore, ultrastructural analysis showed a marked increase in vacuoles in myoferlin-null muscle. These data demonstrate that IGF1 receptor recycling is required for normal myogenesis and that myoferlin is a critical mediator of postnatal muscle growth mediated by IGF1.-Demonbreun, A. R., Posey, A. D., Heretis, K., Swaggart, K. A., Earley, J. U., Pytel, P., McNally, E. M. Myoferlin is required for insulin-like growth factor response and muscle growth.

  17. Thresholds for sterol-limited growth of Daphnia magna: a comparative approach using 10 different sterols.

    Science.gov (United States)

    Martin-Creuzburg, Dominik; Oexle, Sarah; Wacker, Alexander

    2014-09-01

    Arthropods are incapable of synthesizing sterols de novo and thus require a dietary source to cover their physiological demands. The most prominent sterol in animal tissues is cholesterol, which is an indispensable structural component of cell membranes and serves as precursor for steroid hormones. Instead of cholesterol, plants and algae contain a variety of different phytosterols. Consequently, herbivorous arthropods have to metabolize dietary phytosterols to cholesterol to meet their requirements for growth and reproduction. Here, we investigated sterol-limited growth responses of the freshwater herbivore Daphnia magna by supplementing a sterol-free diet with increasing amounts of 10 different phytosterols and comparing thresholds for sterol-limited growth. In addition, we analyzed the sterol composition of D. magna to explore sterol metabolic constraints and bioconversion capacities. We show that dietary phytosterols strongly differ in their potential to support somatic growth of D. magna. The dietary threshold concentrations obtained by supplementing the different sterols cover a wide range (3.5-34.4 μg mg C(-1)) and encompass the one for cholesterol (8.9 μg mg C(-1)), indicating that certain phytosterols are more efficient in supporting somatic growth than cholesterol (e.g., fucosterol, brassicasterol) while others are less efficient (e.g., dihydrocholesterol, lathosterol). The dietary sterol concentration gradients revealed that the poor quality of particular sterols can be alleviated partially by increasing dietary concentrations, and that qualitative differences among sterols are most pronounced at low to moderate dietary concentrations. We infer that the dietary sterol composition has to be considered in zooplankton nutritional ecology to accurately assess potential sterol limitations under field conditions.

  18. Transport and homeostasis of potassium and phosphate: limiting factors for sustainable crop production.

    Science.gov (United States)

    Luan, Mingda; Tang, Ren-Jie; Tang, Yumei; Tian, Wang; Hou, Congong; Zhao, Fugeng; Lan, Wenzhi; Luan, Sheng

    2017-06-01

    Potassium (K) and phosphate (Pi) are both macronutrients essential for plant growth and crop production, but the unrenewable resources of phosphorus rock and potash have become limiting factors for food security. One critical measure to help solve this problem is to improve nutrient use efficiency (NUE) in plants by understanding and engineering genetic networks for ion uptake, translocation, and storage. Plants have evolved multiple systems to adapt to various nutrient conditions for growth and production. Within the NUE networks, transport proteins and their regulators are the primary players for maintaining nutrient homeostasis and could be utilized to engineer high NUE traits in crop plants. A large number of publications have detailed K+ and Pi transport proteins in plants over the past three decades. Meanwhile, the discovery and validation of their regulatory mechanisms are fast-track topics for research. Here, we provide an overview of K+ and Pi transport proteins and their regulatory mechanisms, which participate in the uptake, translocation, storage, and recycling of these nutrients in plants. © The Author 2016. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  19. Fatores determinantes do crescimento infantil Determinant factors of infant growth

    Directory of Open Access Journals (Sweden)

    Sylvia de Azevedo Mello Romani

    2004-03-01

    Full Text Available Esta revisão enfoca os fatores que interferem no crescimento de crianças nos primeiros anos de vida. Foram utilizadas informações de artigos publicados em revistas científicas, teses e publicações de organizações internacionais. O crescimento infantil se constitui em um dos melhores indicadores de saúde da criança e o retardo estatural representa atualmente, a característica antropométrica mais representativa do quadro epidemiológico da desnutrição no Brasil. Ressaltando a importância do fator genético no crescimento, a revisão abrange com maior ênfase a atuação dos fatores extrínsecos, sabendo-se que o processo de crescimento resulta da interação entre a carga genética e os fatores do meio ambiente, os quais premitirão a maior ou menor expressão do potencial genético. Face a comprovada natureza multicausal do crescimento infantil, vários estudos têm sido desenvolvidos, buscando relacionar variáveis biológicas, socioeconômicas, maternas, ambientais, culturais, demográficas, nutricionais, entre outras, com a sua etiologia, seu desenvolvimento e sua manutenção. A revisão apresentada reforça o interesse em investigações sobre o crescimento na primeira infância que devem ser permanentes, devido, principalmente, às repercussões a longo prazo sobre a saúde infantil.This review focuses on factors interfering with growth during the first years of life. Information was collected from articles published in indexed scientific journals, theses, technical books and publications of international organizations. Infant growth is one of the best health indicators, and linear growth retardation is currently the most representative anthropometric characteristic of child nutrition epidemiology in Brazil. The review indicates the value of genetics in growth, focusing, however on the influence of the extrinsic factors. Growth process results from interaction between genetic and environmental factors, determining variation

  20. Impact of epidermal growth factor receptor and transforming growth factor-α on hepatitis C virus-induced hepatocarcinogenesis.

    Science.gov (United States)

    Badawy, Afkar Abdel-Ghany; El-Hindawi, Ali; Hammam, Olfat; Moussa, Mona; Gabal, Samia; Said, Noha

    2015-10-01

    Epidermal growth factor receptor system plays a central hepato-protective and pro-regenerative role in liver. Transforming growth factor-α (TGF-α) is an important autocrine growth regulator of hepatocytes that plays a role in development of hepatocellular carcinoma (HCC) among patients with chronic hepatitis C (CHC). This study was done on 40 core liver biopsies from patients with CHC, 20 liver specimens from HCC cases on top of CHC as well as five normal controls. All were immunohistochemically stained with epidermal growth factor receptor (EGFR) and TGF-α antibodies. Some selected HCC cases were submitted for FISH technique to detect EGFR gene alteration. By immunohistochemistry EGFR and TGF-α were overexpressed in HCC and cirrhotic cases compared to CHC cases without cirrhosis. Also, their expression was stronger in CHC cases with higher grades of activity and stages of fibrosis compared to lower ones. FISH positive results for EGFR were detected in 33.3% of the examined HCC cases. EGFR and TGF-α can be used as predictive markers for activity, fibrosis, and carcinogenesis in CHC patients. Overexpression of EGFR in HCC patients can be promising in selecting those who can get benefit from anti-EGFR target therapy.

  1. The growth strategies of a global pharmaceutical company: a case study of Aspen Pharmacare Holdings Limited

    Directory of Open Access Journals (Sweden)

    Victoria Margaret Hodgon

    2017-05-01

    Full Text Available Given the rapid and sustained growth of Aspen over the past decade, the main aim of this study is to identify and analyze the growth strategies, adopted by Aspen over the period from 2004 to 2014. The research method used was a descriptive study through a single case study of Aspen by analyzing secondary data in the form of publicly available company reports and presentations, as well as financial results, issued between 2004 and 2014. The study finds that, guided by strategic and visionary leadership, Aspen adopted a number of growth strategies including (i organic growth, as a key factor in creating incremental value for Aspen and its stakeholders, (ii inorganic growth, in the form of carefully planned and well executed acquisitions, aligned to the Group strategy, (iii extending territorial coverage through global expansion, particularly into emerging pharmaceutical countries, and (iv ongoing investment in production capabilities as a means of achieving a strategic advantage. Despite the challenges of intense competition, restrictive legislation, pressure on medicine prices, currency volatility and market specific risks, Aspen has delivered double-digit earnings growth to its shareholders for 16 consecutive years.

  2. Torque-Limited Growth of Massive Black Holes in Galaxies Across Cosmic Time

    CERN Document Server

    Anglés-Alcázar, Daniel; Davé, Romeel; Katz, Neal; Kollmeier, Juna A; Oppenheimer, Benjamin D

    2013-01-01

    We combine cosmological hydrodynamic simulations with analytic models to evaluate the role of galaxy-scale gravitational torques on the evolution of massive black holes at the centres of star-forming galaxies. We confirm and extend our earlier results to show that torque-limited growth yields black holes and host galaxies evolving on average along the Mbh-Mbulge relation from early times down to z = 0 and that convergence onto the scaling relation occurs independent of the initial conditions and with no need for mass averaging through mergers or additional self-regulation processes. Smooth accretion dominates the long-term evolution, with black hole mergers with mass ratios >1:5 representing typically a small fraction of the total growth. Winds from the accretion disk are required to eject significant mass to suppress black hole growth, but there is no need for coupling this wind to galactic-scale gas to regulate black holes in a non-linear feedback loop. Torque-limited growth yields a close-to-linear relatio...

  3. Growth Hormone and Insulin-like Growth Factor 1: New Endocrine Therapies in Cardiology?

    Science.gov (United States)

    Clark, R

    1997-10-01

    The hormones growth hormone (GH) and insulin-like growth factor 1 (IGF-1) play a dominant role in whole body growth and metabolism. This is reflected in the use of human GH (hGH) in GH-deficient children to stimulate growth and in GH-deficient adults to reduce visceral fat mass. Recent data suggest that hGH may improve cardiac function in patients with heart failure, so there is current interest in methods to raise GH-IGF levels, including the testing of agents that release GH from the pituitary, administering IGF-1, and most recently, long-acting formulations of hGH. It is hoped that this ongoing integration of cardiology and endocrinology will uncover the pathophysiology of some cardiovascular diseases and yield new treatments based on the hormones of the GH axis. (Trends Cardiovasc Med 1997;7:264-268). © 1997, Elsevier Science Inc.

  4. Inhibition of platelet-derived growth factor signaling prevents muscle fiber growth during skeletal muscle hypertrophy.

    Science.gov (United States)

    Sugg, Kristoffer B; Korn, Michael A; Sarver, Dylan C; Markworth, James F; Mendias, Christopher L

    2017-03-01

    The platelet-derived growth factor receptors alpha and beta (PDGFRα and PDGFRβ) mark fibroadipogenic progenitor cells/fibroblasts and pericytes in skeletal muscle, respectively. While the role that these cells play in muscle growth and development has been evaluated, it was not known whether the PDGF receptors activate signaling pathways that control transcriptional and functional changes during skeletal muscle hypertrophy. To evaluate this, we inhibited PDGFR signaling in mice subjected to a synergist ablation muscle growth procedure, and performed analyses 3 and 10 days after induction of hypertrophy. The results from this study indicate that PDGF signaling is required for fiber hypertrophy, extracellular matrix production, and angiogenesis that occur during muscle growth. © 2017 Federation of European Biochemical Societies.

  5. Soluble vascular endothelial growth factor in various blood transfusion components

    DEFF Research Database (Denmark)

    Nielsen, Hans Jørgen; Werther, K; Mynster, T;

    1999-01-01

    BACKGROUND: Blood transfusion may reduce survival after curative surgery for solid tumors. This may be related to extracellular content of cancer growth factors present in transfusion components. Vascular endothelial growth factor (VEGF) is a potent stimulator of angiogenesis in solid tumors....... The potential content of VEGF in various blood components for transfusion was evaluated. STUDY DESIGN AND METHODS: Soluble VEGF (sVEGF, isotype 165) was determined by an enzyme-linked immunosorbent assay (EIA) in serum and plasma samples and in lysed cells from healthy volunteers. Subsequently, total content...... of platelet-derived soluble plasminogen activator inhibitor type 1 (sPAI-1) was determined by an EIA in the same samples. Finally, the extracellular accumulation of sVEGF was determined in nonfiltered WB and SAGM blood during storage for 35 days and in BCP pools during storage for 7 days. RESULTS...

  6. Soluble vascular endothelial growth factor in various blood transfusion components

    DEFF Research Database (Denmark)

    Nielsen, Hans Jørgen; Werther, K; Mynster, T

    1999-01-01

    BACKGROUND: Blood transfusion may reduce survival after curative surgery for solid tumors. This may be related to extracellular content of cancer growth factors present in transfusion components. Vascular endothelial growth factor (VEGF) is a potent stimulator of angiogenesis in solid tumors....... The potential content of VEGF in various blood components for transfusion was evaluated. STUDY DESIGN AND METHODS: Soluble VEGF (sVEGF, isotype 165) was determined by an enzyme-linked immunosorbent assay (EIA) in serum and plasma samples and in lysed cells from healthy volunteers. Subsequently, total content......-reduced PRP. The sVEGF accumulated significantly in WB, SAGM blood, and BCP pools, depending on the storage time. CONCLUSION: The sVEGF (isotype 165) appears to be present in various blood transfusion components, depending on storage time....

  7. Growth factors in idiopathic pulmonary fibrosis: relative roles

    Directory of Open Access Journals (Sweden)

    Allen Jeremy T

    2001-11-01

    Full Text Available Abstract Treatment of idiopathic pulmonary fibrosis patients has evolved very slowly; the fundamental approach of corticosteroids alone or in combination with other immunosuppressive agents has had little impact on long-term survival. The continued use of corticosteroids is justified because of the lack of a more effective alternative. Current research indicates that the mechanisms driving idiopathic pulmonary fibrosis reflect abnormal, dysregulated wound healing within the lung, involving increased activity and possibly exaggerated responses by a spectrum of profibrogenic growth factors. An understanding of the roles of these growth factors, and the way in which they modulate events at cellular level, could lead to more targeted therapeutic strategies, improving patients' quality of life and survival.

  8. Transforming growth factor-β and smooth muscle differentiation

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    Transforming growth factor(TGF)-β family members are multifunctional cytokines regulating diverse cel- lular functions such as growth,adhesion,migration, apoptosis,and differentiation.TGF-βs elicit their effects via specific typeⅠand typeⅡserine/threonine kinase receptors and intracellular Smad transcription factors. Knockout mouse models for the different components of the TGF-β signaling pathway have revealed their critical roles in smooth muscle cell(SMC)differentia- tion.Genetic studies in humans have linked mutations in these signaling components to specific cardiovascular disorders such as aorta aneurysm and congenital heart diseases due to SMC defects.In this review,the current understanding of TGF-β function in SMC differentiation is highlighted,and the role of TGF-βsignaling in SMC- related diseases is discussed.

  9. Transfer of a Catabolic Pathway for Chloromethane in Methylobacterium Strains Highlights Different Limitations for Growth with Chloromethane or with Dichloromethane

    Directory of Open Access Journals (Sweden)

    Joshua Michener

    2016-07-01

    Full Text Available Chloromethane is an ozone-depleting gas, produced predominantly from natural sources, that provides an important carbon source for microbes capable of consuming it. Chloromethane catabolism has been difficult to study owing to the challenging genetics of its native microbial hosts. Since the pathways for chloromethane catabolism show evidence of horizontal gene transfer, we reproduced this transfer process in the laboratory to generate new chloromethane-catabolizing strains in tractable hosts. We demonstrate that six putative accessory genes improve chloromethane catabolism, though heterologous expression of only one of the six is strictly necessary for growth on chloromethane. In contrast to growth of Methylobacterium strains with the closely-related compound dichloromethane, we find that chloride export does not limit growth on chloromethane and, in general, that the ability of a strain to grow on dichloromethane is uncorrelated with its ability to grow on chloromethane. This heterologous expression system allows us to investigate the components required for effective chloromethane catabolism and the factors that limit effective catabolism after horizontal transfer.

  10. Connective Tissue Growth Factor Expression in Human Bronchial Epithelial Cells

    Institute of Scientific and Technical Information of China (English)

    Amrita DOSANJH

    2006-01-01

    Connective tissue growth factor (CTGF) is a cysteine-rich protein that promotes extracellular matrix deposition. CTGF is selectively induced by transforming growth factor β and des-Arg kallidin in lung fibroblasts and increases steady-state mRNA levels of α type I collagen, 5α-integrin and fibronectin in fibroblasts. Bronchial epithelial cells have been proposed to functionally interact with lung fibroblasts. We therefore investigated if bronchial epithelial cells are able to synthesize CTGF. Human bronchial epithelial cells were grown to subconfluence in standard growth media. Proliferating cells grown in small airway growth media were harvested following starvation for up to 24 h. Expression of CTGF transcripts was measured by PCR. Immunocytochemistry was also completed using a commercially available antibody.The cells expressed readily detectable CTGF transcripts. Starvation of these cells resulted in a quantitative decline of CTGF transcripts. Direct sequencing of the PCR product identified human CTGF. Immunocytochemistry confirmed intracellular CTGF in the cells and none in negative control cells. We conclude that bronchial epithelial cells could be a novel source of CTGF. Bronchial epithelial cell-derived CTGF could thus directly influence the deposition of collagen in certain fibrotic lung diseases.

  11. Epidermal growth factor in mammary glands and milk from rats

    DEFF Research Database (Denmark)

    Thulesen, J; Raaberg, Lasse; Nexø, Ebba

    1993-01-01

    Epidermal growth factor (EGF) is one of the major growth-promoting agents in milk. Using immunohistochemistry we localized EGF in the mammary glands of lactating rats to the luminal border of the secretory cells. Following proteolytic pretreatment of the histological sections, the EGF-immunoreact......Epidermal growth factor (EGF) is one of the major growth-promoting agents in milk. Using immunohistochemistry we localized EGF in the mammary glands of lactating rats to the luminal border of the secretory cells. Following proteolytic pretreatment of the histological sections, the EGF......-immunoreactivity was revealed homogeneously in the cytoplasm of the secretory cells, which might suggest that EGF is present as a precursor molecule in the mammary glands. Altered glucose metabolism during lactation results in secondary hypoinsulinaemia in the lactating rat. As insulin is also known to affect lactation...... in several species, we treated normal lactating rats daily with insulin and studied the effect on the composition of milk. A significant increase in the content of total protein and milk fat was observed after a few days of insulin-treatment, as compared to a control group [total protein: 50 (36-97) g/l vs...

  12. Endocrine fibroblast growth factor FGF19 promotes prostate cancer progression.

    Science.gov (United States)

    Feng, Shu; Dakhova, Olga; Creighton, Chad J; Ittmann, Michael

    2013-04-15

    Prostate cancer is the most common visceral malignancy and the second leading cause of cancer deaths in US men. There is broad evidence that fibroblast growth factor (FGF) receptors are important in prostate cancer initiation and progression, but the contribution of particular FGFs in this disease is not fully understood. The FGF family members FGF19, FGF21, and FGF23 comprise a distinct subfamily that circulate in serum and act in an endocrine manner. These endocrine FGFs require α-Klotho (KL) and/or β-Klotho (KLB), two related single-pass transmembrane proteins restricted in their tissue distribution, to act as coreceptors along with classic FGF receptors (FGFR) to mediate potent biologic activity. Here we show that FGF19 is expressed in primary and metastatic prostate cancer tissues, where it functions as an autocrine growth factor. Exogenous FGF19 promoted the growth, invasion, adhesion, and colony formation of prostate cancer cells at low ligand concentrations. FGF19 silencing in prostate cancer cells expressing autocrine FGF19 decreased invasion and proliferation in vitro and tumor growth in vivo. Consistent with these observations, KL and/or KLB were expressed in prostate cancer cells in vitro and in vivo, raising the possibility that additional endocrine FGFs may also exert biologic effects in prostate cancer. Our findings support the concept that therapies targeting FGFR signaling may have efficacy in prostate cancer and highlight FGF19 as a relevant endocrine FGF in this setting.

  13. Insulin-like growth factor- I and factors affecting it in thalassemia major

    Directory of Open Access Journals (Sweden)

    Ashraf T Soliman

    2015-01-01

    Full Text Available Despite improvement of blood transfusion regimens and iron chelation therapy growth and maturational delay, cardiomyopathy, endocrinopathies and osteoporosis still occur in good number of thalassemic patients. Decreased IGF-1 secretion occurs in the majority of the thalassemic patients particularly those with growth and pubertal delay. Many factors contribute to this decreased synthesis of IGF-I including disturbed growth hormone (GH - insulin-like growth factor - I (IGF-I axis. The possible factors contributing to low IGF-I synthesis in thalassemia and the possible interaction between low IGF-I secretion and the occurrence of these complications is discussed in this mini-review. Improvement of IGF-I secretion in thalassemic patients should be intended to improve linear growth and bone mineral accretion in thalassemic patients. This can be attained through adequate correction of anemia and proper chelation, nutritional supplementation (increasing caloric intake, correction of vitamin D and zinc deficiencies, induction of puberty and correction of hypogonadism at the proper time and treating GH deficiency. This review paper provides a summary of the current state of knowledge regarding IGF-I and factors affecting it in patients with thalassaemia major (TM. Search on PubMed and reference lists of articles with the term ′IGF-I, GH, growth, thalassemia, thyroxine, anemia, vitamin D, and zinc′ was carried out. A hundred and forty-eight articles were found and used in the write up and the data analyzed was included in this report.

  14. Fibroblast Growth Factor 23 in Long-Duration Spaceflight

    Science.gov (United States)

    Bokhari, R.; Zwart, S. R.; Fields, E.; Heer, M.; Sibonga, J.; Smith, S. M.

    2015-01-01

    Many nutritional factors influence bone, from the basics of calcium and vitamin D, to factors which influence bone through acid/base balance, including protein, sodium, and more. Fibroblast growth factor 23 (FGF23) is a recently identified factor, secreted from osteocytes, which is involved in classic (albeit complex) feedback loops controlling phosphorus homeostasis through both vitamin D and parathyroid hormone (PTH) (1, 2). As osteocytes are gravity sensing cells, it is important to determine if there are changes in FGF23 during spaceflight. In extreme cases, such as chronic kidney disease, FGF23 levels are highly elevated. FGF23 imbalances, secondary to dietary influences, may contribute to skeletal demineralization and kidney stone risk during spaceflight.

  15. Neuroprotective effects of ultrasound-guided nerve growth factor injections after sciatic nerve injury

    OpenAIRE

    Hong-fei Li; Yi-ru Wang; Hui-ping Huo; Yue-xiang Wang; Jie Tang

    2015-01-01

    Nerve growth factor (NGF) plays an important role in promoting neuroregeneration after peripheral nerve injury. However, its effects are limited by its short half-life; it is therefore important to identify an effective mode of administration. High-frequency ultrasound (HFU) is increasingly used in the clinic for high-resolution visualization of tissues, and has been proposed as a method for identifying and evaluating peripheral nerve damage after injury. In addition, HFU is widely used for g...

  16. Vancouver Experience of Recombinant Human Platelet-Derived Growth Factor.

    Science.gov (United States)

    Younger, Alistair; Penner, Murray; Montijo, Harvey E

    2016-12-01

    Joint arthrodesis utilizing autogenous bone graft remains the gold standard of treatment in fusion procedures of the foot and ankle. Graft harvest, however, has been associated with increased morbidity to patients as well as increased costs. With this in mind, multiple clinical studies have evaluated the efficacy of recombinant human platelet-derived growth factor (rh-PDGF-BB) with beta-tricalcium phosphate (B-TCP) to augment in foot and ankle arthrodesis with favorable results. These factors have led to the increased use of rh-PDGF-BB with B-TCP in Vancouver with good clinical results. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. Nerve Growth Factor: A Focus on Neuroscience and Therapy

    Science.gov (United States)

    Aloe, Luigi; Rocco, Maria Luisa; Omar Balzamino, Bijorn; Micera, Alessandra

    2015-01-01

    Nerve growth factor (NGF) is the firstly discovered and best characterized neurotrophic factor, known to play a critical protective role in the development and survival of sympathetic, sensory and forebrain cholinergic neurons. NGF promotes neuritis outgrowth both in vivo and in vitro and nerve cell recovery after ischemic, surgical or chemical injuries. Recently, the therapeutic property of NGF has been demonstrated on human cutaneous and corneal ulcers, pressure ulcer, glaucoma, maculopathy and retinitis pigmentosa. NGF eye drops administration is well tolerated, with no detectable clinical evidence of systemic or local adverse effects. The aim of this review is to summarize these biological properties and the potential clinical development of NGF. PMID:26411962

  18. The expression of the epidermal growth factor (EGF) during odontogenesis:

    OpenAIRE

    Peixoto, Breno C.; Integrated Federal School of Diamantina - MG; dos Santos, Cássio R. R.; Integrated Federal School of Diamantina - MG; Canuto, Conceição E.; Integrated Federal School of Diamantina - MG

    2010-01-01

    The objective of this study was to verify, through the technique of Immunohistochemistry, the expression of theepidermal growth factor (EGF) in the odontogenesis of the first upper molar in Mus musculus mice, relating it tothe microscopic morphologic analysis. The sample consisted of 23 animals, with age from the 13th day of intrauterinelife to the 20th day of postnatal life. The results showed EGF being expressed by several tissues and cellsparticipating of the odontogenesis. However the den...

  19. Stem cells and growth factors in wound healing

    OpenAIRE

    Michał Pikuła; Paulina Langa; Paulina Kosikowska; Piotr Trzonkowski

    2015-01-01

    Wound healing is a complex process which depends on the presence of various types of cells, growth factors, cytokines and the elements of extracellular matrix. A wound is a portal of entry for numerous pathogens, therefore during the evolution wound healing process has formed very early, being critical for the survival of every individual. Stem cells, which give rise to their early descendants progenitor cells and subsequently differentiated cells, play a specific role in the process of wound...

  20. Cytokines and growth factors cross-link heparan sulfate

    Science.gov (United States)

    Migliorini, Elisa; Thakar, Dhruv; Kühnle, Jens; Sadir, Rabia; Dyer, Douglas P.; Li, Yong; Sun, Changye; Volkman, Brian F.; Handel, Tracy M.; Coche-Guerente, Liliane; Fernig, David G.; Lortat-Jacob, Hugues; Richter, Ralf P.

    2015-01-01

    The glycosaminoglycan heparan sulfate (HS), present at the surface of most cells and ubiquitous in extracellular matrix, binds many soluble extracellular signalling molecules such as chemokines and growth factors, and regulates their transport and effector functions. It is, however, unknown whether upon binding HS these proteins can affect the long-range structure of HS. To test this idea, we interrogated a supramolecular model system, in which HS chains grafted to streptavidin-functionalized oligoethylene glycol monolayers or supported lipid bilayers mimic the HS-rich pericellular or extracellular matrix, with the biophysical techniques quartz crystal microbalance (QCM-D) and fluorescence recovery after photobleaching (FRAP). We were able to control and characterize the supramolecular presentation of HS chains—their local density, orientation, conformation and lateral mobility—and their interaction with proteins. The chemokine CXCL12α (or SDF-1α) rigidified the HS film, and this effect was due to protein-mediated cross-linking of HS chains. Complementary measurements with CXCL12α mutants and the CXCL12γ isoform provided insight into the molecular mechanism underlying cross-linking. Fibroblast growth factor 2 (FGF-2), which has three HS binding sites, was also found to cross-link HS, but FGF-9, which has just one binding site, did not. Based on these data, we propose that the ability to cross-link HS is a generic feature of many cytokines and growth factors, which depends on the architecture of their HS binding sites. The ability to change matrix organization and physico-chemical properties (e.g. permeability and rigidification) implies that the functions of cytokines and growth factors may not simply be confined to the activation of cognate cellular receptors. PMID:26269427

  1. Purification of human platelet-derived growth factor

    Energy Technology Data Exchange (ETDEWEB)

    Raines, E.W.; Ross, R.

    1985-01-01

    The paper describes a method for purification of human platelet-derived growth factor (PDGF) from outdated platelet-rich plasma (PRP) using commonly available laboratory reagents and yielding a mitogen purified 800,000-fold over the starting material. (/sup 3/H)thymidine incorporation into DNA of cultured cells responsive to PDGF represents the most readily available method to follow its purification and define the biological activity of a purified preparation. Other assays to quantitate PDGF include radioreceptor assay and radioimmunoassay.

  2. Fibroblast growth factor signaling during early vertebrate development.

    Science.gov (United States)

    Böttcher, Ralph T; Niehrs, Christof

    2005-02-01

    Fibroblast growth factors (FGFs) have been implicated in diverse cellular processes including apoptosis, cell survival, chemotaxis, cell adhesion, migration, differentiation, and proliferation. This review presents our current understanding on the roles of FGF signaling, the pathways employed, and its regulation. We focus on FGF signaling during early embryonic processes in vertebrates, such as induction and patterning of the three germ layers as well as its function in the control of morphogenetic movements.

  3. Chance, creativity, and the discovery of the nerve growth factor.

    Science.gov (United States)

    de Romo, Ana Cecilia Rodríguez

    2007-01-01

    This essay analyzes the history of the Nerve Growth Factor (NGF) discovery, relating some of the principles of the theory of scientific creativity to the cognitive and personal qualities of the scientists that participated in the discovery, particularly Rita Levi-Montalcini and Viktor Hamburger. The discovery of NGF is especially attractive for the history of science as it involves chance, luck, creativity, and some extraordinary scientists.

  4. Angiopoietin-related growth factor level in preeclampsia

    OpenAIRE

    2012-01-01

    Abstract Aim. Angiopoietin-related growth factor (AGF) is associated with angiogenesis but it can also affect glucose and energy metabolism. The aim of this study was to determine AGF levels in preeclampsia. Method. The study included 32 women with preeclampsia (preeclampsia group) and 32 non-preeclamptic, healthy, third trimester pregnant women (Control group). We analyzed serum levels of AGF and other biochemical and anthropometric markers in all subjects. Results. Serum AGF levels were sig...

  5. Elevated ability to compete for limited food resources by 'all-fish' growth hormone transgenic common carp Cyprinus carpio.

    Science.gov (United States)

    Duan, M; Zhang, T; Hu, W; Sundström, L F; Wang, Y; Li, Z; Zhu, Z

    2009-10-01

    Food consumption, number of movements and feeding hierarchy of juvenile transgenic common carp Cyprinus carpio and their size-matched non-transgenic conspecifics were measured under conditions of limited food supply. Transgenic fish exhibited 73.3% more movements as well as a higher feeding order, and consumed 1.86 times as many food pellets as their non-transgenic counterparts. After the 10 day experiment, transgenic C. carpio had still not realized their higher growth potential, which may be partly explained by the higher frequency of movements of transgenics and the 'sneaky' feeding strategy used by the non-transgenics. The results indicate that these transgenic fish possess an elevated ability to compete for limited food resources, which could be advantageous after an escape into the wild. It may be that other factors in the natural environment (i.e. predation risk and food distribution), however, would offset this advantage. Thus, these results need to be assessed with caution.

  6. Growth factor deprivation induces cytosolic translocation of SIRT1

    Science.gov (United States)

    Meng, Chengbo; Xing, Da; Wu, Shengnan; Huang, Lei

    2010-02-01

    Sirtuin type 1 (SIRT1), a NAD+-dependent histone deacetylases, plays a critical role in cellular senescence, aging and longevity. In general, SIRT1 is localized in nucleus and is believed as a nuclear protein. Though overexpression of SIRT1 delays senescence, SIRT1-protein levels decline naturally in thymus and heart during aging. In the present studies, we investigated the subcellular localization of SIRT1 in response to growth factor deprivation in African green monkey SV40-transformed kidney fibroblast cells (COS-7). Using SIRT1-EGFP fluorescence reporter, we found that SIRT1 localized to nucleus in physiological conditions. We devised a model enabling cell senescence via growth factor deprivation, and we found that SIRT1 partially translocated to cytosol under the treatment, suggesting a reduced level of SIRT1's activity. We found PI3K/Akt pathway was involved in the inhibition of SIRT1's cytosolic translocation, because inhibition of these kinases significantly decreased the amount of SIRT1 maintained in nucleus. Taken together, we demonstrated that growth factor deprivation induces cytosolic translocation of SIRT1, which suggesting a possible connection between cytoplasm-localized SIRT1 and the aging process.

  7. An extended fractal growth regime in the diffusion limited aggregation including edge diffusion

    Directory of Open Access Journals (Sweden)

    Aritra Ghosh

    2016-01-01

    Full Text Available We have investigated on-lattice diffusion limited aggregation (DLA involving edge diffusion and compared the results with the standard DLA model. For both cases, we observe the existence of a crossover from the fractal to the compact regime as a function of sticking coefficient. However, our modified DLA model including edge diffusion shows an extended fractal growth regime like an earlier theoretical result using realistic growth models and physical parameters [Zhang et al., Phys. Rev. Lett. 73 (1994 1829]. While the results of Zhang et al. showed the existence of the extended fractal growth regime only on triangular but not on square lattices, we find its existence on the square lattice. There is experimental evidence of this growth regime on a square lattice. The standard DLA model cannot characterize fractal morphology as the fractal dimension (Hausdorff dimension, DH is insensitive to morphology. It also predicts DH = DP (the perimeter dimension. For the usual fractal structures, observed in growth experiments on surfaces, the perimeter dimension can differ significantly (DH ≠ DP depending on the morphology. Our modified DLA model shows minor sensitivity to this difference.

  8. INTRAUTERINE GROWTH RETARDATION AT FULL TERM PREGNANCIES WITH ENDOCRINE FACTORS

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Objective To investigate the relationship between intrauterine growth retardation (IUGR) and en docrine parameters so as to assess the effects of the main endocrine factors on IUGR. The concentrations of growth hormone (GH), insulin, T3, T4 and TSH were measured in umbilical cord blood, amniotic fluid and maternal serum. Methods The samples were collected from 23 pregnant women who were diagnosed as the full term IUGR, 42 normal full term pregnant women with normal infants' weight were taken as control. Growth hormone and insulin were mea sured by radioimmunoassay. T3, T4 and TSH were investigated by micro-radioimmunoassay. Results The concentra tions of growth hormone, insulin and T4 in umbilical cord blood were lower in IUGR than that in control group(GH 4. 63μg/L vs 7.01μg/L, insulin 10. 68μIU/ml vs 31.44μIU/ml, T4 87. 39nmol/L vs 138. 10nmol/L. P <0. 05, 0. 05 and 0. 05, respectively). The TSH concentration in umbilical cord blood was higher in IUGR than in control group (10. 84μmIU/L vs 5. 75μmIU/L, P <0. 01). The concentration of growth hormone in maternal serum and the concen tration of insulin in amniotic fluid were also lower in IUGR group than in control group(GH 1.77μg/L vs 2.74μg/L, P <0. 01, insulin 5. 84μIU/mi vs 15. 64μIU/ml, P <0. 01). Conclusion This study confirms that full term neonates with IUGR are abnormal in endocrine factors. The inadequacy of growth hormone may be one of the causes of IUGR. The relative scarcity of growth hormone and insulin seems to be a factor to compromise the fetus' metabolism. Be sides, the early hypothyrosis of infants with IUGR might protect them from unfavorable environment in the uterine.

  9. Socio-demographic factors related to functional limitations and care dependency among older Egyptians

    NARCIS (Netherlands)

    Boggatz, Thomas; Farid, Tamer; Mohammedin, Ahmed; Dijkstra, Ate; Lohrmann, Christa; Dassen, Theo

    P>Title. Socio-demographic factors related to functional limitations and care dependency among older Egyptians. Aim. This paper is a report of a study determining the relationship of socio-demographic factors to functional limitations and care dependency among older care recipients and non-care

  10. Socio-demographic factors related to functional limitations and care dependency among older Egyptians

    NARCIS (Netherlands)

    Boggatz, Thomas; Farid, Tamer; Mohammedin, Ahmed; Dijkstra, Ate; Lohrmann, Christa; Dassen, Theo

    2010-01-01

    P>Title. Socio-demographic factors related to functional limitations and care dependency among older Egyptians. Aim. This paper is a report of a study determining the relationship of socio-demographic factors to functional limitations and care dependency among older care recipients and non-care reci

  11. Development of management quality system for metallurgical enterprise based on Balanced Scorecard with limiting factors

    Directory of Open Access Journals (Sweden)

    Galina Ledneva

    2009-12-01

    Full Text Available The article considers inefficiency of the existing quality management systems (QMS based on standards ISO series 9000. The authors offer integrated QMS with limiting factors on Balanced Scorecard. The Balanced Scorecard with limiting factors helps to efficiently direct process of continuous improvement and achieve top-priority criteria in quality management domain.

  12. Plant defences limit herbivore population growth by changing predator-prey interactions.

    Science.gov (United States)

    Kersch-Becker, Mônica F; Kessler, André; Thaler, Jennifer S

    2017-09-13

    Plant quality and predators are important factors affecting herbivore population growth, but how they interact to regulate herbivore populations is not well understood. We manipulated jasmonate-induced plant resistance, exposure to the natural predator community and herbivore density to test how these factors jointly and independently affect herbivore population growth. On low-resistance plants, the predator community was diverse and abundant, promoting high predator consumption rates. On high-resistance plants, the predator community was less diverse and abundant, resulting in low predator consumption rate. Plant resistance only directly regulated aphid population growth on predator-excluded plants. When predators were present, plant resistance indirectly regulated herbivore population growth by changing the impact of predators on the herbivorous prey. A possible mechanism for the interaction between plant resistance and predation is that methyl salicylate, a herbivore-induced plant volatile attractive to predators, was more strongly induced in low-resistance plants. Increased plant resistance reduced predator attractant lures, preventing predators from locating their prey. Low-resistance plants may regulate herbivore populations via predators by providing reliable information on prey availability and increasing the effectiveness of predators. © 2017 The Author(s).

  13. E2F1 transcription factor and its impact on growth factor and cytokine signaling.

    Science.gov (United States)

    Ertosun, Mustafa Gokhan; Hapil, Fatma Zehra; Osman Nidai, Ozes

    2016-10-01

    E2F1 is a transcription factor involved in cell cycle regulation and apoptosis. The transactivation capacity of E2F1 is regulated by pRb. In its hypophosphorylated form, pRb binds and inactivates DNA binding and transactivating functions of E2F1. The growth factor stimulation of cells leads to activation of CDKs (cyclin dependent kinases), which in turn phosphorylate Rb and hyperphosphorylated Rb is released from E2F1 or E2F1/DP complex, and free E2F1 can induce transcription of several genes involved in cell cycle entry, induction or inhibition of apoptosis. Thus, growth factors and cytokines generally utilize E2F1 to direct cells to either fate. Furthermore, E2F1 regulates expressions of various cytokines and growth factor receptors, establishing positive or negative feedback mechanisms. This review focuses on the relationship between E2F1 transcription factor and cytokines (IL-1, IL-2, IL-3, IL-6, TGF-beta, G-CSF, LIF), growth factors (EGF, KGF, VEGF, IGF, FGF, PDGF, HGF, NGF), and interferons (IFN-α, IFN-β and IFN-γ).

  14. Does pollen limitation affect population growth of the endangered Dracocephalum austriacum L.?

    NARCIS (Netherlands)

    S. Castro; T. Dostálek; S. van der Meer; G. Oostermeijer; Z. Münzbergová

    2015-01-01

    Reproductive strategies can have significant consequences for the viability of plant populations. Still, the effects of lower fruit set due to pollen limitation on plant demography and population persistence have rarely been explored. The objectives of this study were to assess the ecological factor

  15. Effects of Basic Fibroblast Growth Factor and Insulin-like Growth Factor on Cultured Cartilage Cells from Skate Raja porasa

    Institute of Scientific and Technical Information of China (English)

    樊廷俊; 晋凌云; 汪小锋

    2003-01-01

    Effects of basic fibroblast growth factor (bFGF) and insulin-like growth factor II (IGF-II) on cartilage cells from proboscis of skate, Raja porasa Günther, were investigated in this study. The cartilage cells were cultured in 20% FBS-supplemented MEM medium at 24℃. Twelve hours after culture initiation, the cartilage cells were treated with bFGF and IGF-II at different concentration combinations. It was found that 20 ng/ml of bFGF or 80 ng/ml of IGF-II was enough to have obvious stimulating effect on the growth and division of skate cartilage cells. Test of bFGF and IGF-II together, revealed that 20 ng/ml of bFGF and 80 ng/ml of IGF-II together had the best stimulating effect on the growth and division of skate cartilage cells. The cartilage cells cultured could form a monolayer at day 7.

  16. Fibroblast growth factor receptor 4 (FGFR4) and fibroblast growth factor 19 (FGF19) autocrine enhance breast cancer cells survival.

    Science.gov (United States)

    Tiong, Kai Hung; Tan, Boon Shing; Choo, Heng Lungh; Chung, Felicia Fei-Lei; Hii, Ling-Wei; Tan, Si Hoey; Khor, Nelson Tze Woei; Wong, Shew Fung; See, Sze-Jia; Tan, Yuen-Fen; Rosli, Rozita; Cheong, Soon-Keng; Leong, Chee-Onn

    2016-09-06

    Basal-like breast cancer is an aggressive tumor subtype with poor prognosis. The discovery of underlying mechanisms mediating tumor cell survival, and the development of novel agents to target these pathways, is a priority for patients with basal-like breast cancer. From a functional screen to identify key drivers of basal-like breast cancer cell growth, we identified fibroblast growth factor receptor 4 (FGFR4) as a potential mediator of cell survival. We found that FGFR4 mediates cancer cell survival predominantly via activation of PI3K/AKT. Importantly, a subset of basal-like breast cancer cells also secrete fibroblast growth factor 19 (FGF19), a canonical ligand specific for FGFR4. siRNA-mediated silencing of FGF19 or neutralization of extracellular FGF19 by anti-FGF19 antibody (1A6) decreases AKT phosphorylation, suppresses cancer cell growth and enhances doxorubicin sensitivity only in the FGFR4+/FGF19+ breast cancer cells. Consistently, FGFR4/FGF19 co-expression was also observed in 82 out of 287 (28.6%) primary breast tumors, and their expression is strongly associated with AKT phosphorylation, Ki-67 staining, higher tumor stage and basal-like phenotype. In summary, our results demonstrated the presence of an FGFR4/FGF19 autocrine signaling that mediates the survival of a subset of basal-like breast cancer cells and suggest that inactivation of this autocrine loop may potentially serve as a novel therapeutic intervention for future treatment of breast cancers.

  17. Placental growth factor is a survival factor for tumor endothelial cells and macrophages.

    Science.gov (United States)

    Adini, Avner; Kornaga, Tad; Firoozbakht, Farshid; Benjamin, Laura E

    2002-05-15

    The vascular endothelial growth factor (VEGF)-related factor, placental growth factor (PlGF),has been shown recently to play an important role in pathological VEGF-driven angiogenesis. In this study, we examine the effects of mPlGF/PlGF-2 overexpression in tumors grown from glioma cells containing a tetracycline-regulated mPlGF cDNA. Overexpression of mPlGF leads to increased tumor growth and vascular survival. When tetracycline is used to abruptly withdraw mPlGF overexpression, we see increased apoptosis in both vascular cells and macrophages. In addition, PlGF-2 induces survival gene expression and inhibits apoptosis in vitro. Thus, we propose that PlGF-2 contributes to tumor angiogenesis by providing increased survival function to endothelial cells and macrophages.

  18. Growth factors, glucose and insulin kinetics after low dose growth hormone in HIV - lipodystrophy

    DEFF Research Database (Denmark)

    Haugaard, Steen B; Andersen, Ove; Flyvbjerg, Allan

    2006-01-01

    and temporary reduction in insulin sensitivity was caused by a reduction in non-oxidative glucose metabolism (n=5). GH-administration reduced hepatic extraction of insulin alleviating the demand for insulin secretion (n=5). No adverse effects of GH were detected. CONCLUSIONS: As judged from effects......OBJECTIVES: Low-dose growth hormone (GH) administration has been suggested as a treatment for HIV-lipodystrophy. METHODS: Postglucose GH-secretion, kinetics of insulin-like growth factors (IGFs), insulin, and glucose metabolism were examined in six male HIV-infected lipodystrophic patients (two...

  19. Growth factors, glucose and insulin kinetics after low dose growth hormone in HIV - lipodystrophy

    DEFF Research Database (Denmark)

    Haugaard, Steen B; Andersen, Ove; Flyvbjerg, Allan

    2006-01-01

    OBJECTIVES: Low-dose growth hormone (GH) administration has been suggested as a treatment for HIV-lipodystrophy. METHODS: Postglucose GH-secretion, kinetics of insulin-like growth factors (IGFs), insulin, and glucose metabolism were examined in six male HIV-infected lipodystrophic patients (two...... on circulating IGF-I, glucose metabolism, and insulin kinetics, 0.7 mg/day of GH may be expedient for treatment of HIV-infected males with lipodystrophy. Whether the patients' glucose metabolic status matters for the IGF-response to low-dose GH-therapy awaits further investigation....

  20. Design and characteristics of cytotoxic fibroblast growth factor 1 conjugate for fibroblast growth factor receptor-targeted cancer therapy

    Directory of Open Access Journals (Sweden)

    Szlachcic A

    2016-08-01

    Full Text Available Anna Szlachcic, Malgorzata Zakrzewska, Michal Lobocki, Piotr Jakimowicz, Jacek Otlewski Department of Protein Engineering, Faculty of Biotechnology, University of Wroclaw, Wroclaw, Poland Abstract: Fibroblast growth factor receptors (FGFRs are attractive candidate cancer therapy targets as they are overexpressed in multiple types of tumors, such as breast, prostate, bladder, and lung cancer. In this study, a natural ligand of FGFR, an engineered variant of fibroblast growth factor 1 (FGF1V, was conjugated to a potent cytotoxic drug, monomethyl auristatin E (MMAE, and used as a targeting agent for cancer cells overexpressing FGFRs, similar to antibodies in antibody–drug conjugates. The FGF1V–valine–citrulline–MMAE conjugate showed a favorable stability profile, bound FGFRs on the cell surface specifically, and efficiently released the drug (MMAE upon cleavage by the lysosomal protease cathepsin B. Importantly, the conjugate showed a prominent cytotoxic effect toward cell lines expressing FGFR. FGF1V–vcMMAE was highly cytotoxic at concentrations even an order of magnitude lower than those found for free MMAE. This effect was FGFR-specific as cells lacking FGFR did not show any increased mortality. Keywords: fibroblast growth factor 1, FGF receptor, targeted cancer therapy, cytotoxic conjugates, FGFR-dependent cancer, MMAE, auristatin

  1. Age and growth of mangrove red snapper Lutjanus argentimaculatus at its cool-water-range limits.

    Science.gov (United States)

    Piddocke, T P; Butler, G L; Butcher, P A; Stewart, J; Bucher, D J; Christidis, L

    2015-05-01

    This study investigates the age and growth of Lutjanus argentimaculatus at its southern (cooler) range limits in eastern Australia. Specimens were collected from New South Wales and southern Queensland between November 2011 and December 2013. Fork lengths (LF ) ranged from 190 to 1019 mm, and ages ranged from 2+ to 57+ years. Growth was described by the von Bertalanffy growth function with coefficients L∞ = 874·92 mm, K = 0·087 year(-1) and t0 = -2·76 years. Estimates of the instantaneous natural mortality rate (M) ranged from 0·072 to 0·25. The LF (mm) and mass (W; g) relationship was represented by the equation: W=2·647×10-5LF2·92. The maximum age of 57+ years is the oldest reported for any lutjanid and comparisons with tropical studies suggest that the age-based demography of L. argentimaculatus follows a latitudinal gradient. High maximum ages and low natural mortality rates indicate considerable vulnerability to overexploitation at the species' cool-water-range limits. These results demonstrate the need to identify underlying processes driving latitudinal gradients in fish demography.

  2. A comparison of additional treatment processes to limit particle accumulation and microbial growth during drinking water distribution.

    Science.gov (United States)

    Liu, G; Lut, M C; Verberk, J Q J C; Van Dijk, J C

    2013-05-15

    Water quality changes, particle accumulation and microbial growth occurring in pilot-scale water distribution systems fed with normally treated and additional treated groundwater were monitored over a period of almost one year. The treatment processes were ranked in the following order: nanofiltration (NF) > (better than) ultrafiltration (UF) > ion exchange (IEX) for limiting particle accumulation. A different order was found for limiting overall microbial growth: NF > IEX > UF. There were strong correlations between particle load and particle accumulation, and between nutrient load and microbial growth. It was concluded that particle accumulation can be controlled by reducing the particle load in water treatment plants; and the microbial growth can be better controlled by limiting organic nutrients rather than removing biomass in water treatment plants. The major focus of this study was on microbial growth. The results demonstrated that growth occurred in all types of treated water, including the phases of bulk water, biofilm and loose deposits. Considering the growth in different phases, similar growth in bulk water was observed for all treatments; NF strongly reduced growth both in loose deposits and in biofilm; UF promoted growth in biofilm, while strongly limiting growth in loose deposits. IEX had good efficiency in between UF and NF, limiting both growths in loose deposits and in biofilm. Significant growth was found in loose deposits, suggesting that loose deposit biomass should be taken into account for growth evaluation and/or prediction. Strong correlations were found between microbial growth and pressure drop in a membrane fouling simulator which proved that a membrane fouling simulator can be a fast growth predictor (within a week). Different results obtained by adenosine triphosphate and flow cytometry cell counts revealed that ATP can accurately describe both suspended and particle-associated biomass, and flow cytometry files of TCC measurements needs

  3. The algal growth-limiting nutrient of lakes located at Mexico’s Mesa Central

    Directory of Open Access Journals (Sweden)

    Fernando W. Bernal-Brooks

    2016-03-01

    Full Text Available This paper reports on the algal growth-limiting nutrients of five lakes located on Mexico’s Mesa Central - a topic poorly known in the regional limnology of Mexico. The five case studies involved three contiguous watersheds of Michoacán State and provided a trophic state variation from mesotrophic to hypereutrophic; the case studies included Lakes Zirahuén, Pátzcuaro, Teremendo, Cuitzeo and the Cointzio Reservoir. The fieldwork involved the collection of physical and chemical data (including nutrients from each case study during the dry and rainy seasons of 2010. Additionally, water samples (1 L were obtained and filtered (0.45 µm in the laboratory to keep the nutrient content available for bioassays. The chemical analyses suggested a phosphorus (P limitation in the Cointzio Reservoir, Lake Teremendo and Lake Zirahuén relative to an N:P>16:1. There was a nitrogen (N limitation at three sampling stations of Lake Pátzcuaro, with an N:P<16:1. As result of the bioassays conducted in July 2012, the Cointzio Reservoir and Lake Teremendo appeared to be P-limited and Lake Pátzcuaro appeared to be N-limited at three sampling stations. Lake Zirahuén showed seasonal variation, with an N limitation during the dry season and a P limitation during the wet season. Those cases with similar results from both methods confirmed the limiting nutrient identification. Lake Cuitzeo, Lake Zirahuén (dry season, and the shallowest sampling station in Lake Pátzcuaro produced unclear results because of divergent outcomes. In terms of the algal growth potential, the Cointzio Reservoir remained unaltered from one season to the next. However, for most of the lakes (with the exception of Lake Pátzcuaro sites 2 and 4, the rainy season provided a dilution effect. Effective lake management depends on a clear recognition of such elements that are in control of the aquatic productivity. In the area of Michoacán, both N and P may act as limiting nutrients.

  4. An investigation on different factors influencing growth of banking deposits

    Directory of Open Access Journals (Sweden)

    Zahra Houshmand Neghabi

    2013-01-01

    Full Text Available Banking deposit is the primary source of contributing to economy and it is important to understand what factors influence such deposits. In this paper, we present an empirical study to find the relationship between banking deposit and other important factors such as capital market, money market, commodity market, foreign exchange rates such as US dollar and Euro exchange rates to local currency (Rials. We gather the data over the period of 2010-2012 and using ordinary least square technique study different hypotheses. All t-student values are statistically meaningful when the level of significance is ten percent and some of the parameters are even meaningful when the level of significance is five percent. The results indicate that the rate of bank deposit is negatively associated with commodity market growth rate (-.001995, US dollar exchange rate (-0.004167, banking industry growth rate (-0.278826 and moving average (-0.940418. In addition, dependent variable is positively associated with Euro exchange growth rate (0.005676.

  5. Fibroblast growth factor (FGF) signaling in development and skeletal diseases.

    Science.gov (United States)

    Teven, Chad M; Farina, Evan M; Rivas, Jane; Reid, Russell R

    2014-12-01

    Fibroblast growth factors (FGF) and their receptors serve many functions in both the developing and adult organism. Humans contain 18 FGF ligands and four FGF receptors (FGFR). FGF ligands are polypeptide growth factors that regulate several developmental processes including cellular proliferation, differentiation, and migration, morphogenesis, and patterning. FGF-FGFR signaling is also critical to the developing axial and craniofacial skeleton. In particular, the signaling cascade has been implicated in intramembranous ossification of cranial bones as well as cranial suture homeostasis. In the adult, FGFs and FGFRs are crucial for tissue repair. FGF signaling generally follows one of three transduction pathways: RAS/MAP kinase, PI3/AKT, or PLCγ. Each pathway likely regulates specific cellular behaviors. Inappropriate expression of FGF and improper activation of FGFRs are associated with various pathologic conditions, unregulated cell growth, and tumorigenesis. Additionally, aberrant signaling has been implicated in many skeletal abnormalities including achondroplasia and craniosynostosis. The biology and mechanisms of the FGF family have been the subject of significant research over the past 30 years. Recently, work has focused on the therapeutic targeting and potential of FGF ligands and their associated receptors. The majority of FGF-related therapy is aimed at age-related disorders. Increased understanding of FGF signaling and biology may reveal additional therapeutic roles, both in utero and postnatally. This review discusses the role of FGF signaling in general physiologic and pathologic embryogenesis and further explores it within the context of skeletal development.

  6. Hepatocyte growth factor in renal failure: promise and reality.

    Science.gov (United States)

    Vargas, G A; Hoeflich, A; Jehle, P M

    2000-04-01

    Can science discover some secrets of Greek mythology? In the case of Prometheus, we can now suppose that his amazing hepatic regeneration was caused by a peptide growth factor called hepatocyte growth factor (HGF). Increasing evidence indicates that HGF acts as a multifunctional cytokine on different cell types. This review addresses the molecular mechanisms that are responsible for the pleiotropic effects of HGF. HGF binds with high affinity to its specific tyrosine kinase receptor c-met, thereby stimulating not only cell proliferation and differentiation, but also cell migration and tumorigenesis. The three fundamental principles of medicine-prevention, diagnosis, and therapy-may be benefited by the rational use of HGF. In renal tubular cells, HGF induces mitogenic and morphogenetic responses. In animal models of toxic or ischemic acute renal failure, HGF acts in a renotropic and nephroprotective manner. HGF expression is rapidly up-regulated in the remnant kidney of nephrectomized rats, inducing compensatory growth. In a mouse model of chronic renal disease, HGF inhibits the progression of tubulointerstitial fibrosis and kidney dysfunction. Increased HGF mRNA transcripts were detected in mesenchymal and tubular epithelial cells of rejecting kidney. In transplanted patients, elevated HGF levels may indicate renal rejection. When HGF is considered as a therapeutic agent in human medicine, for example, to stimulate kidney regeneration after acute injury, strategies need to be developed to stimulate cell regeneration and differentiation without an induction of tumorigenesis.

  7. Insulin-like growth factors and kidney disease.

    Science.gov (United States)

    Bach, Leon A; Hale, Lorna J

    2015-02-01

    Insulin-like growth factors (IGF-1 and IGF-2) are necessary for normal growth and development. They are related structurally to proinsulin and promote cell proliferation, differentiation, and survival, as well as insulin-like metabolic effects, in most cell types and tissues. In particular, IGFs are important for normal pre- and postnatal kidney development. IGF-1 mediates many growth hormone actions, and both growth hormone excess and deficiency are associated with perturbed kidney function. IGFs affect renal hemodynamics both directly and indirectly by interacting with the renin-angiotensin system. In addition to the IGF ligands, the IGF system includes receptors for IGF-1, IGF-2/mannose-6-phosphate, and insulin, and a family of 6 high-affinity IGF-binding proteins that modulate IGF action. Disordered regulation of the IGF system has been implicated in a number of kidney diseases. IGF activity is enhanced in early diabetic nephropathy and polycystic kidneys, whereas IGF resistance is found in chronic kidney failure. IGFs have a potential role in enhancing stem cell repair of kidney injury. Most IGF actions are mediated by the tyrosine kinase IGF-1 receptor, and inhibitors recently have been developed. Further studies are needed to determine the optimal role of IGF-based therapies in kidney disease. Copyright © 2015 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

  8. Direct regulation of rRNA transcription by fibroblast growth factor 2.

    Science.gov (United States)

    Sheng, Zhi; Liang, Yanping; Lin, Chih-Yin; Comai, Lucio; Chirico, William J

    2005-11-01

    Fibroblast growth factor 2 (FGF-2), which is highly expressed in developing tissues and malignant cells, regulates cell growth, differentiation, and migration. Five isoforms (18 to approximately 34 kDa) of FGF-2 are derived from alternative initiation codons of a single mRNA. The 18-kDa FGF-2 isoform is released from cells by a nonclassical secretory pathway and regulates gene expression by binding to cell surface receptors. This isoform also localizes to the nucleolus, raising the possibility that it may directly regulate ribosome biogenesis, a rate-limiting process in cell growth. Although several growth factors have been shown to accumulate in the nucleolus, their function and mechanism of action remain unclear. Here we show that 18-kDa FGF-2 interacts with upstream binding factor (UBF), an architectural transcription factor essential for rRNA transcription. The maximal activation of rRNA transcription in vitro by 18-kDa FGF-2 requires UBF. The 18-kDa FGF-2 localizes to rRNA genes and is necessary for the full activation of pre-rRNA synthesis in vivo. Our results demonstrate that 18-kDa FGF-2 directly regulates rRNA transcription.

  9. Environmental estrogens inhibit growth of rainbow trout (Oncorhynchus mykiss) by modulating the growth hormone-insulin-like growth factor system.

    Science.gov (United States)

    Hanson, Andrea M; Kittilson, Jeffrey D; Martin, Lincoln E; Sheridan, Mark A

    2014-01-15

    Although environmental estrogens (EE) have been found to disrupt a wide variety of developmental and reproductive processes in vertebrates, there is a paucity of information concerning their effects on organismal growth, particularly postembryonic growth. In this study, we exposed juvenile rainbow trout (Oncorhynchus mykiss) to 17β-estradiol (E2) β-sitosterol (βS), or 4-n-nonylphenol (NP) to assess the effects of EE on overall organismal growth and on the growth hormone-insulin-like-growth factor (GH-IGF) system. EE treatment significantly reduced food conversion, body condition, and body growth. EE-inhibited growth resulted from alterations in peripheral elements of the GH-IGF system, which includes multiple GH receptors (GHRs), IGFs, and IGF receptors (IGFRs). In general, E2, βS, and NP reduced the expression of GHRs, IGFs, and IGFRs; however, the effects varied in an EE-, tissue-, element type-specific manner. For example, in liver, E2 was more efficacious than either βS, and NP in reducing GHR expression, and the effect of E2 was greater on GHR 1 than GHR2 mRNA. By contrast, in gill, all EEs affected GHR expression in a similar manner and there was no difference in the effect on GHR1 and GHR 2 mRNA. With regard to IGF expression, all EEs reduced hepatic IGF1 and IGF2 mRNA levels, whereas as in gill, only E2 and NP significantly reduced IGF1 and IGF2 expression. Lastly, E2 and NP reduced the expression of IGFR1A and IGFR1B mRNA expression similarly in gill and red and white muscle, whereas βS had no effect on expression of IGFR mRNAs. These findings indicate that EEs disrupt post-embryonic growth by reducing GH sensitivity, IGF production, and IGF sensitivity.

  10. Growth decline linked to warming-induced water limitation in hemi-boreal forests.

    Science.gov (United States)

    Wu, Xiuchen; Liu, Hongyan; Guo, Dali; Anenkhonov, Oleg A; Badmaeva, Natalya K; Sandanov, Denis V

    2012-01-01

    Hemi-boreal forests, which make up the transition from temperate deciduous forests to boreal forests in southern Siberia, have experienced significant warming without any accompanying increase in precipitation during the last 80 years. This climatic change could have a profound impact on tree growth and on the stability of forest ecosystems in this region, but at present evidence for these impacts is lacking. In this study, we report a recent dramatic decline in the growth of hemi-boreal forests, based on ring width measurements from three dominant tree-species (Pinus sylvestris, Larix sibirica and Larix gmelinii), sampled from eight sites in the region. We found that regional tree growth has become increasingly limited by low soil water content in the pre- and early-growing season (from October of the previous year to July of the current year) over the past 80 years. A warming-induced reduction in soil water content has also increased the climate sensitivity of these three tree species. Beginning in the mid-1980s, a clear decline in growth is evident for both the pine forests and the larch forests, although there are increasing trends in the proxy of soil water use efficiencies. Our findings are consistent with those from other parts of the world and provide valuable insights into the regional carbon cycle and vegetation dynamics, and should be useful for devising adaptive forest management strategies.

  11. Growth decline linked to warming-induced water limitation in hemi-boreal forests.

    Directory of Open Access Journals (Sweden)

    Xiuchen Wu

    Full Text Available Hemi-boreal forests, which make up the transition from temperate deciduous forests to boreal forests in southern Siberia, have experienced significant warming without any accompanying increase in precipitation during the last 80 years. This climatic change could have a profound impact on tree growth and on the stability of forest ecosystems in this region, but at present evidence for these impacts is lacking. In this study, we report a recent dramatic decline in the growth of hemi-boreal forests, based on ring width measurements from three dominant tree-species (Pinus sylvestris, Larix sibirica and Larix gmelinii, sampled from eight sites in the region. We found that regional tree growth has become increasingly limited by low soil water content in the pre- and early-growing season (from October of the previous year to July of the current year over the past 80 years. A warming-induced reduction in soil water content has also increased the climate sensitivity of these three tree species. Beginning in the mid-1980s, a clear decline in growth is evident for both the pine forests and the larch forests, although there are increasing trends in the proxy of soil water use efficiencies. Our findings are consistent with those from other parts of the world and provide valuable insights into the regional carbon cycle and vegetation dynamics, and should be useful for devising adaptive forest management strategies.

  12. Bioactive food components, cancer cell growth limitation and reversal of glycolytic metabolism.

    Science.gov (United States)

    Keijer, Jaap; Bekkenkamp-Grovenstein, Melissa; Venema, Dini; Dommels, Yvonne E M

    2011-06-01

    Cancer cells are resistant to apoptosis and show a shift in energy production from mitochondrial oxidative phosphorylation to cytosolic glycolysis. Apoptosis resistance and metabolic reprogramming are linked in many cancer cells and both processes center on mitochondria. Clearly, mutated cancer cells escape surveillance and turn into selfish cells. However, many of the mechanisms that operate cellular metabolic control still function in cancer cells. This review describes the metabolic importance of glucose and glutamine, glycolytic enzymes, oxygen, growth cofactors and mitochondria and focuses on the potential role of bioactive food components, including micronutrients. The role of B- and A-vitamin cofactors in (mitochondrial) metabolism is highlighted and the cancer protective potential of omega-3 fatty acids and several polyphenols is discussed in relation to metabolic reprogramming, including the mechanisms that may be involved. Furthermore, it is shown that cancer cell growth reduction by limiting the growth cofactor folic acid seems to be associated with reversal of metabolic reprogramming. Altogether, reversal of metabolic reprogramming may be an attractive strategy to increase susceptibility to apoptotic surveillance. Food bioactive components that affect various aspects of metabolism may be important tools to reverse glycolytic to oxidative metabolism and enhance sensitivity to apoptosis. The success of such a strategy may depend on several actors, acting in concert. Growth cofactors may be one of these, which call for careful (re)evaluation of their function in normal and in cancer metabolism.

  13. Cutaneous adverse events of epidermal growth factor receptor inhibitors: A retrospective review of 99 cases

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    Kumutnart Chanprapaph

    2015-01-01

    Full Text Available Background: Previous reports regarding the cutaneous adverse events of epidermal growth factor receptor inhibitors are mostly limited to small case reports and case series, mainly involving Caucasian patients. Aims: We describe the trends in the clinical presentation of Asian patients who had cutaneous adverse events induced by epidermal growth factor receptor inhibitors and to explore the relationship between skin adverse events and tumor response. Methods: From 2006 to 2010, medical records of Thai patients with non-small cell lung cancer receiving epidermal growth factor receptor inhibitors were retrieved and analyzed. Results: In all, 99 patients were reviewed and analyzed. Erlotinib and gefitinib were commenced in 75 (75.8% and 24 (24.2% patients, respectively. Cutaneous adverse events occurred in 43 (57.3% patients receiving erlotinib and in 15 (62.5% patients receiving gefitinib. The most common adverse event was xerosis (52.5%. Less common adverse events included papulo-pustular eruption (27.3%, erythematous maculopapular rash (11.1%, mucositis (6.7%, paronychia (5.1%, and trichomegaly (2%. Elderly patients had a higher occurrence of xerosis. The presence of cutaneous adverse events was significantly higher in subjects who had a tumor response. Limitations: The limitations of study include its retrospective nature, and the initial screening of cutaneous adverse events was done by non-dermatologists. Conclusions: Cutaneous adverse events due to epidermal growth factor receptor inhibitors are not uncommon in the Asian population. We found a positive correlation between the occurrences of cutaneou adverse events and tumor response supporting the view that they are surrogate markers for therapeutic response.

  14. Some Empirical Aspects regarding the Relationship between Inflation and Economic Growth in Romania – the Speed Limit Effect

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    Andrei BIRMAN

    2011-12-01

    Full Text Available This study briefly presents theoretical aspects related to the relationship between inflation and economic growth and provides an empirical study for the Romanian economy, for the period 2000 – 2011. The econometric methodology used is that of vector auto-regressions.The results showed that a sudden increase in the change of the output gap (i.e. a shock to the growth rate of the output gap does not determine an increase in CPI. Hence, the hypothesis of the existence of a speed limit effect in Romania is rejected. In concrete terms, this means that the monetary authorities should not fear for eventual inflationary pressures when sudden increases of demand arise, if the output gap is negative (the potential output is higher that the effective output. The National Bank of Romania may avoid, therefore, taking some monetary policy decisions meant to temper the rise in inflation (as would have been the case if a speed limit effect was present but which would have induced unnecessary volatility into the output. However, the study indicates that National Bank of Romania should communicate to the public the state of the economy in order to timely anchor the inflation expectations. This is a very important aspect, since the inflation expectations firmly react to a shock into the growth rate of the output gap, i.e. to a strong increase in the effective output.The study also showed a positive response of the growth rate of the output gap to a positive shock in inflation, with a maximum effect after three quarters. This shows that the inflation was mainly driven by demand factors in the analysed period, with the consumers increasing current consumption in order to avoid the future higher prices and with the economic agents increasing the supply such as to maximise the unitary profits. Also, this result shows a rather inelastic demand or a possible captivity of consumers in the face of producers.

  15. Effects of Hypergravity Rearing on Growth Hormone and Insulin-Like Growth Factor in Rat Pups

    Science.gov (United States)

    Baer, L. A.; Chowdhury, J. H.; Grindeland, R. E.; Wade, C. E.; Ronca, A. E.

    2003-01-01

    Body weights of rat pups reared during exposure to hypergravity (hg) are significantly reduced relative to 1 g controls. In the present study, we examined in hg-reared rat pups two major contributors to growth and development, namely growth hormone (GH) and insulin-like growth factor-1 (IGF-1). Beginning on Gestational day (G)11 of the rats 22 day pregnancy, rat dams and their litters were continuously exposed to either 1.5-g or 2.0-g. On Postnatal day (P)l0, plasma GH and IGF-1 were analyzed using radioimmunoassay (RIA). Both hormones were significantly elevated in hg pups relative to 1-g control pups. Together, these findings suggest that GH and IGF-1 are not primary determinants of reduced body weights observed in hg-reared pups. The significant elevations in pup GH and IGF-1 may be related to increased physical stimulation in hypergravity.

  16. Growth hormone is a growth factor for the differentiated pancreatic beta-cell

    DEFF Research Database (Denmark)

    Linde, S; Welinder, B S; Billestrup, N;

    1989-01-01

    The regulation of the growth of the pancreatic beta-cell is poorly understood. There are previous indications of a role of GH in the growth and insulin production of the pancreatic islets. In the present study we present evidence for a direct long-term effect of GH on proliferation and insulin...... biosynthesis of pancreatic beta-cells in monolayer culture. In culture medium RPMI 1640 supplemented with 2% normal human serum islets or dissociated islet cells from newborn rats maintained their insulin-producing capacity. When supplemented with 1-1000 ng/ml pituitary or recombinant human GH the islet cells....... It is concluded that GH is a potent growth factor for the differentiated pancreatic beta-cell....

  17. Growth factors and myometrium: biological effects in uterine fibroid and possible clinical implications

    Science.gov (United States)

    Ciarmela, Pasquapina; Islam, Md. Soriful; Reis, Fernando M.; Gray, Peter C.; Bloise, Enrrico; Petraglia, Felice; Vale, Wylie; Castellucci, Mario

    2011-01-01

    BACKGROUND Growth factors are proteins secreted by a number of cell types that are capable of modulating cellular growth, proliferation and cellular differentiation. It is well accepted that uterine cellular events such as proliferation and differentiation are regulated by sex steroids and their actions in target tissues are mediated by local production of growth factors acting through paracrine and/or autocrine mechanisms. Myometrial mass is ultimately modified in pregnancy as well as in tumour conditions such as leiomyoma and leiomyosarcoma. Leiomyomas, also known as fibroids, are benign tumours of the uterus, considered to be one of the most frequent causes of infertility in reproductive years in women. METHODS For this review, we searched the database MEDLINE and Google Scholar for articles with content related to growth factors acting on myometrium; the findings are hereby reviewed and discussed. RESULTS Different growth factors such as epidermal growth factor (EGF), transforming growth factor-α (TGF-α), heparin-binding EGF (HB-EGF), acidic fibroblast growth factor (aFGF), basic fibroblast growth factor (bFGF), vascular endothelial growth factor (VEGF), insulin-like growth factor (IGF), platelet-derived growth factor (PDGF) and TGF-β perform actions in myometrium and in leiomyomas. In addition to these growth factors, activin and myostatin have been recently identified in myometrium and leiomyoma. CONCLUSIONS Growth factors play an important role in the mechanisms involved in myometrial patho-physiology. PMID:21788281

  18. A Rigorous Sharp Interface Limit of a Diffuse Interface Model Related to Tumor Growth

    Science.gov (United States)

    Rocca, Elisabetta; Scala, Riccardo

    2017-06-01

    In this paper, we study the rigorous sharp interface limit of a diffuse interface model related to the dynamics of tumor growth, when a parameter ɛ, representing the interface thickness between the tumorous and non-tumorous cells, tends to zero. More in particular, we analyze here a gradient-flow-type model arising from a modification of the recently introduced model for tumor growth dynamics in Hawkins-Daruud et al. (Int J Numer Math Biomed Eng 28:3-24, 2011) (cf. also Hilhorst et al. Math Models Methods Appl Sci 25:1011-1043, 2015). Exploiting the techniques related to both gradient flows and gamma convergence, we recover a condition on the interface Γ relating the chemical and double-well potentials, the mean curvature, and the normal velocity.

  19. Myoferlin is required for insulin-like growth factor response and muscle growth

    Science.gov (United States)

    Demonbreun, Alexis R.; Posey, Avery D.; Heretis, Konstantina; Swaggart, Kayleigh A.; Earley, Judy U.; Pytel, Peter; McNally, Elizabeth M.

    2010-01-01

    Insulin-like growth factor (IGF) is a potent stimulus of muscle growth. Myoferlin is a membrane-associated protein important for muscle development and regeneration. Myoferlin-null mice have smaller muscles and defective myoblast fusion. To understand the mechanism by which myoferlin loss retards muscle growth, we found that myoferlin-null muscle does not respond to IGF1. In vivo after IGF1 infusion, control muscle increased myofiber diameter by 25%, but myoferlin-null muscle was unresponsive. Myoblasts cultured from myoferlin-null muscle and treated with IGF1 also failed to show the expected increase in fusion to multinucleate myotubes. The IGF1 receptor colocalized with myoferlin at sites of myoblast fusion. The lack of IGF1 responsiveness in myoferlin-null myoblasts was linked directly to IGF1 receptor mistrafficking as well as decreased IGF1 signaling. In myoferlin-null myoblasts, the IGF1 receptor accumulated into large vesicular structures. These vesicles colocalized with a marker of late endosomes/lysosomes, LAMP2, specifying redirection from a recycling to a degradative pathway. Furthermore, ultrastructural analysis showed a marked increase in vacuoles in myoferlin-null muscle. These data demonstrate that IGF1 receptor recycling is required for normal myogenesis and that myoferlin is a critical mediator of postnatal muscle growth mediated by IGF1.—Demonbreun, A. R., Posey, A. D., Heretis, K., Swaggart, K. A., Earley, J. U., Pytel, P., McNally, E. M. Myoferlin is required for insulin-like growth factor response and muscle growth. PMID:20008164

  20. VASCULAR ENDOTHELIAL GROWTH FACTOR IN HEALTH AND DISEASE: A REVIEW

    Directory of Open Access Journals (Sweden)

    Niranjan Gopal

    2016-10-01

    Full Text Available BACKGROUND Vascular Endothelial Growth Factor (VEGF has been implicated as a key molecule, which regulates physiological angiogenesis. VEGF exerts its molecular actions through Receptor Tyrosine Kinases (RTKs VEGFR-1 and VEGFR-2, differ in signaling properties. VEGF plays a vital role in embryogenesis, growth and reproduction. VEGF as a mediator of pathological angiogenesis is associated with proliferation and micrometastasis of various tumours, ocular disorders involving neovascularisation, pre-eclampsia, etc. The pathogenesis of micro and macrovascular complications of diabetes mellitus and the role of VEGF is being studied extensively. Currently, several pharmacological interventions based on VEGF inhibitors and receptor antagonists have been tried to combat the pathological angiogenesis in a wide gamut of disorders. This review attempts to put together important properties, mechanism of action and the role of VEGF in common diseased states. CONCLUSION Effects of VEGF are widespread and have been implicated in several disease states. Therapeutic modalities targeting VEGF have been tried with success in recent years.

  1. Concentration Variations of Growth Factors in Colostrum and Normal Milk of Sows

    Institute of Scientific and Technical Information of China (English)

    LI Yao; SHAN An-shan; FENG Zi-ke

    2004-01-01

    An experiment was conducted to determine the concentration variation of epidermal growth factors (EGF), include insulin-like growth factor - Ⅰ (IGF- I ), transforming growth factor-beta(TGF-β), and basic fibroblast growth factor (bFGF) in colostrum and normal milk of sows within 35 days after parturition. The results showed that the concentration of EGF, IGF- I , TGF-β, bFGF was significantly higher in colostrum than that in normal milk. The concentration of these growth factors in colostrum was significantly decreased with the stage lapse of lactation, and then they remained stable in normal milk. Parity had a slight effect on the concentration of these growth factors.

  2. Optimization of plant mineral nutrition under growth-limiting conditions in a lunar greenhouse

    Science.gov (United States)

    Zaets, I.; Voznyuk, T.; Kovalchuk, M.; Rogutskyy, I.; Lukashov, D.; Mytrokhyn, O.; Mashkovska, S.; Foing, B.; Kozyrovska, N.

    It may be assumed that the first plants in a lunar base will play a main role in forming a protosoil of acceptable fertility needed for purposively growing second generation plants like wheat, rice, tulips, etc. The residues of the first-generation plants could be composted and transformed by microorganisms into a soil-like substrate within a loop of regenerative life support system. The lunar regolith may be used as a substrate for plant growth at the very beginning of a mission to reduce its cost. The use of microbial communities for priming plants will allow one to facilitate adaption to stressful conditions and to support the plant development under growth limiting conditions. Well-defined plant-associated bacteria were used for growing three cultivars to colonize French marigold (Tagetes patula L.) in anorthosite, a substrate of low bioavailability, analogous to a lunar rock. The consortium was composed of plant growth promoting rhizobacteria and the bacterium Paenibacillus sp. IMBG156 which stimulated seed germination, better plant development, and finally, the flowering of inoculated tagetes. In contrast, control plants grew poorly in the anorthosite and practically did not survive until flowering. Analysis of bacterial community composition showed that all species colonized plant roots, however, the rate of colonization depended on the allelopatic characteristics of marigold varieties. Bacteria of consortium were able to liberate some elements (Ca, Fe, Mn, Si, Ni, Cu, Zn) from substrate anorthosite. Plant colonization by mixed culture of bacterial strains resulted in the increase of accumulation of K, Mg, Mn by the plant and in the lowering of the level of toxic metal accumulation. It was assumed that a rationally assembled consortium of bacterial strains promoted germination of marygold seeds and supported the plant development under growth limiting conditions by means of bioleaching plant essential nutritional elements and by protecting the plant against

  3. Blockade of nonhormonal fibroblast growth factors by FP-1039 inhibits growth of multiple types of cancer.

    Science.gov (United States)

    Harding, Thomas C; Long, Li; Palencia, Servando; Zhang, Hongbing; Sadra, Ali; Hestir, Kevin; Patil, Namrata; Levin, Anita; Hsu, Amy W; Charych, Deborah; Brennan, Thomas; Zanghi, James; Halenbeck, Robert; Marshall, Shannon A; Qin, Minmin; Doberstein, Stephen K; Hollenbaugh, Diane; Kavanaugh, W Michael; Williams, Lewis T; Baker, Kevin P

    2013-03-27

    The fibroblast growth factor (FGF) pathway promotes tumor growth and angiogenesis in many solid tumors. Although there has long been interest in FGF pathway inhibitors, development has been complicated: An effective FGF inhibitor must block the activity of multiple mitogenic FGF ligands but must spare the metabolic hormone FGFs (FGF-19, FGF-21, and FGF-23) to avoid unacceptable toxicity. To achieve these design requirements, we engineered a soluble FGF receptor 1 Fc fusion protein, FP-1039. FP-1039 binds tightly to all of the mitogenic FGF ligands, inhibits FGF-stimulated cell proliferation in vitro, blocks FGF- and vascular endothelial growth factor (VEGF)-induced angiogenesis in vivo, and inhibits in vivo growth of a broad range of tumor types. FP-1039 antitumor response is positively correlated with RNA levels of FGF2, FGF18, FGFR1c, FGFR3c, and ETV4; models with genetic aberrations in the FGF pathway, including FGFR1-amplified lung cancer and FGFR2-mutated endometrial cancer, are particularly sensitive to FP-1039-mediated tumor inhibition. FP-1039 does not appreciably bind the hormonal FGFs, because these ligands require a cell surface co-receptor, klotho or β-klotho, for high-affinity binding and signaling. Serum calcium and phosphate levels, which are regulated by FGF-23, are not altered by administration of FP-1039. By selectively blocking nonhormonal FGFs, FP-1039 treatment confers antitumor efficacy without the toxicities associated with other FGF pathway inhibitors.

  4. Diabetes, growth hormone-insulin-like growth factor pathways and association to benign prostatic hyperplasia.

    Science.gov (United States)

    Wang, Zongwei; Olumi, Aria F

    2011-01-01

    Diabetes significantly increases the risk of benign prostatic hyperplasia (BPH) and low urinary tract symptoms (LUTS). The major endocrine aberration in connection with the metabolic syndrome is hyperinsulinemia. Insulin is an independent risk factor and a promoter of BPH. Insulin resistance may change the risk of BPH through several biological pathways. Hyperinsulinemia stimulates the liver to produce more insulin-like growth factor (IGF), another mitogen and an anti-apoptotic agent which binds insulin receptor/IGF receptor and stimulates prostate growth. The levels of IGFs and IGF binding proteins (IGFBPs) in prostate tissue and in blood are associated with BPH risk, with the regulation of circulating androgen and growth hormone. Stromal-epithelial interactions play a critical role in the development and growth of the prostate gland and BPH. Previously, we have shown that the expression of c-Jun in the fibroblastic stroma can promote secretion of IGF-I, which stimulates prostate epithelial cell proliferation through activating specific target genes. Here, we will review the epidemiologic, clinical, and molecular findings which have evaluated the relation between diabetes and development of BPH.

  5. Correlation between Nerve Growth Factor (NGF) with Brain Derived Neurotropic Factor (BDNF) in Ischemic Stroke Patient

    OpenAIRE

    Islam, Andi Asadul

    2016-01-01

    - The neurotrophins nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF) is a family of polypeptides that play critical role during neuronal development, appear to mediate protective role on neurorepair in ischemic stroke. Naturally in adult brain neurorepair process consist of: angiogenesis, neurogenesis, and neuronal plasticity, it can also be stimulated by endogenous neurorepair. In this study we observed correlation between NGF and BDNF ischemic stroke patient's onset...

  6. Thyroid hormones regulate fibroblast growth factor receptor signaling during chondrogenesis.

    Science.gov (United States)

    Barnard, Joanna C; Williams, Allan J; Rabier, Bénédicte; Chassande, Olivier; Samarut, Jacques; Cheng, Sheue-Yann; Bassett, J H Duncan; Williams, Graham R

    2005-12-01

    Childhood hypothyroidism causes growth arrest with delayed ossification and growth-plate dysgenesis, whereas thyrotoxicosis accelerates ossification and growth. Thyroid hormone (T(3)) regulates chondrocyte proliferation and is essential for hypertrophic differentiation. Fibroblast growth factors (FGFs) are also important regulators of chondrocyte proliferation and differentiation, and activating mutations of FGF receptor-3 (FGFR3) cause achondroplasia. We investigated the hypothesis that T(3) regulates chondrogenesis via FGFR3 in ATDC5 cells, which undergo a defined program of chondrogenesis. ATDC5 cells expressed two FGFR1, four FGFR2, and one FGFR3 mRNA splice variants throughout chondrogenesis, and expression of each isoform was stimulated by T(3) during the first 6-12 d of culture, when T(3) inhibited proliferation by 50%. FGFR3 expression was also increased in cells treated with T(3) for 21 d, when T(3) induced an earlier onset of hypertrophic differentiation and collagen X expression. FGFR3 expression was reduced in growth plates from T(3) receptor alpha-null mice, which exhibit skeletal hypothyroidism, but was increased in T(3) receptor beta(PV/PV) mice, which display skeletal thyrotoxicosis. These findings indicate that FGFR3 is a T(3)-target gene in chondrocytes. In further experiments, T(3) enhanced FGF2 and FGF18 activation of the MAPK-signaling pathway but inhibited their activation of signal transducer and activator of transcription-1. FGF9 did not activate MAPK or signal transducer and activator of transcription-1 pathways in the absence or presence of T(3). Thus, T(3) exerted differing effects on FGFR activation during chondrogenesis depending on which FGF ligand stimulated the FGFR and which downstream signaling pathway was activated. These studies identify novel interactions between T(3) and FGFs that regulate chondrocyte proliferation and differentiation during chondrogenesis.

  7. GROWTH DIFFERENTIATION FACTOR-5 STIMULATES THE GROWTH AND ANABOLIC METABOLISM OF ARTICULAR CHONDROCYTES

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Objective To observe the effect of growth differentiation factor-5 (GDF-5) on the growth and anabolic metabolism of articular chondrocytes. Methods The articular chondrocytes isolated from rats were treated with various concentrations of rmGDF-5, and the growth of chondrocytes measured by MTT assay, the cellular cartilage matrices formation detected sulfated glycosaminoglycan by Alcian blue staining and type Ⅱcollagen by RT-PCR. Results After 7 days culture, MTT assay showed that GDF-5 enhanced the growth of chondrocytes in a dose-dependent manner, RT-PCR showed that GDF-5 clearly induced the synthesis of type Ⅱ collagen because of the col2a1 mRNA band more and more strong in a dose-dependent. Chondrocytes were cultured with GDF-5 for 14 days, the intensity of Alcian blue staining was greatly enhanced, especially, at a high concentration of blue-stainable material in a concentration-dependent manner and in a does-dependent manner. Conclusion GDF-5 enhanced the growth of mature articular chondrocytes, and stimulated the cellular cartilage matrices formation in mono-layer culture.

  8. A role for platelet-derived growth factor-BB in rat postpneumonectomy compensatory lung growth.

    Science.gov (United States)

    Yuan, Shizeng; Hannam, Vicky; Belcastro, Rosetta; Cartel, Nicholas; Cabacungan, Judy; Wang, Jinxia; Diambomba, Yenge; Johnstone, Leslie; Post, Martin; Tanswell, A Keith

    2002-07-01

    Unilateral pneumonectomy leads to compensatory growth in the residual lung, the mediators of which are largely unknown. We hypothesized, based on its other known roles in lung cell growth, that platelet-derived growth factor (PDGF)-BB would be an essential mediator of postpneumonectomy compensatory lung growth. Left-sided pneumonectomies were performed on 21-d-old rats, for comparison with sham-operated or unoperated control animals. Body weights were not different between groups. Right lung weights and DNA content were significantly increased (p < 0.05), compared with controls, by 10 d after pneumonectomy. The rate of DNA synthesis was maximal on d 5 postpneumonectomy. Total right lung PDGF-B mRNA and PDGF-BB protein increased after pneumonectomy, but were apparently tightly regulated, relative to total right lung beta-actin mRNA and protein content, respectively. However, PDGF-BB expression after pneumonectomy was apparently not purely constitutive, in that daily i.p. injections of a truncated soluble PDGF beta-receptor both reduced activation of the native PDGF beta-receptor, and attenuated increased lung DNA synthesis on d 3 after pneumonectomy. These findings are consistent with a critical role for PDGF-BB in postpneumonectomy lung growth.

  9. Growth differentiation factor-5 stimulates the growth and anabolic metabolism of articular chondrocytes

    Institute of Scientific and Technical Information of China (English)

    Xu Peng; Guo Xiong; Yao Jianfeng; Zhang Yingang; Klaus von der Mark

    2005-01-01

    Objective: To observe the effect of growth differentiation factor-5 (GDF-5) on the growth and anabolic metabolism of articular chondrocytes. Methods: The articular chondrocytes isolated from rats were treated with various concentrations of rmGDF-5, and the growth of chondrocytes measured by MTT assay, the cellular cartilage matrices formation detected sulfated glycosaminoglycan by Alcian blue staining and type Ⅱ collagen by RT-PCR,the collagen phenotypic expression of chondrocytes detected by immunofluorescence. Results: After 7 days culture,MTT assay showed that GDF-5 enhanced the growth of chondrocytes in a dose-dependent manner, RT-PCR showed that GDF-5 clearly induced the synthesis of type Ⅱ collagen because of the col2a1 mRNA band more and more strong in a dose-dependent. Chondrocytes were cultured with GDF-5 for 14 days, the intensity of Alcian blue staining was greatly enhanced, especially, at a high concentration of 1000ng/ml, and GDF-5 enhanced the accumulation of the Alcian blue-stainable material in a concentration-dependent manner and in a does-dependent manner. Chondrocytes were cultured with GDF-5 for 21 days, immunofluorescent staining of type Ⅱ collagen was clear, the type Ⅰ and X collagen were negative. Conclusion: GDF-5 enhanced the growth of mature articular chondrocytes, and stimulated the cellular cartilage matrices formation, but did not change the collagen phenotypic expression of chondrocytes in mono-layer culture.

  10. Growth Differentiation Factor-5 Stimulates the Growth and Anabolic Metabolism of Articular Chondrocytes

    Institute of Scientific and Technical Information of China (English)

    Xu Peng; Yao Jianfeng; Guo Xiong; Zhang Yingang; Klaus von der Mark

    2009-01-01

    Objective: To observe the effect of growth differentiation factor-5 (GDF-5) on the growth and anabolic metabolism of articular chondrocytes. Methods: The articular chondrocytes isolated from rats were treated with various concentrations of rmGDF-5, and the growth of chondrocytes measured by MTr assay, the cellular cartilage matrices formation detected sulfated glycosaminoglycan by Alcian blue staining and type 11 collagen by RT-PCR, the collagen phenotypic expression of chondrocytes detected by immunofluorescence. Results: After 7 days culture, MTF assay showed that GDF-5 enhanced the growth of ehondrocytes in a dose-dependent manner, RT-PCR showed that GDF-5 clearly induced the synthesis of type Ⅱ collagen because of the colal mRNA band more and more strong in a dose-dependent. Chondrocytes were cultured with GDF-5 for 14 days, the intensity of Alcian blue staining was gready enhanced, especially, at a high concentration of 1000ng/ml, and GDF-5 enhanced the accumulation of the Alcian blue-stainable material in a concentration-dependent manner and in a does-dependent manner. Chondrocytes were cultured with GDF-5 for 21 days, immunofluorescent staining of type Ⅱ collagen was clear, the type Ⅰ and Ⅹ collagen were negative. Conclusion: GDF-5 enhanced the growth of mature articular chon-drocytes, and stimulated the cellular cartilage matrices formation, but did not change the collagen phenotypic ex-pression of chondrocytes in mono-layer culture.

  11. Tissue Engineering Using Transfected Growth-Factor Genes

    Science.gov (United States)

    Madry, Henning; Langer, Robert S.; Freed, Lisa E.; Trippel, Stephen; Vunjak-Novakovic, Gordana

    2005-01-01

    A method of growing bioengineered tissues includes, as a major component, the use of mammalian cells that have been transfected with genes for secretion of regulator and growth-factor substances. In a typical application, one either seeds the cells onto an artificial matrix made of a synthetic or natural biocompatible material, or else one cultures the cells until they secrete a desired amount of an extracellular matrix. If such a bioengineered tissue construct is to be used for surgical replacement of injured tissue, then the cells should preferably be the patient s own cells or, if not, at least cells matched to the patient s cells according to a human-leucocyteantigen (HLA) test. The bioengineered tissue construct is typically implanted in the patient's injured natural tissue, wherein the growth-factor genes enhance metabolic functions that promote the in vitro development of functional tissue constructs and their integration with native tissues. If the matrix is biodegradable, then one of the results of metabolism could be absorption of the matrix and replacement of the matrix with tissue formed at least partly by the transfected cells. The method was developed for articular chondrocytes but can (at least in principle) be extended to a variety of cell types and biocompatible matrix materials, including ones that have been exploited in prior tissue-engineering methods. Examples of cell types include chondrocytes, hepatocytes, islet cells, nerve cells, muscle cells, other organ cells, bone- and cartilage-forming cells, epithelial and endothelial cells, connective- tissue stem cells, mesodermal stem cells, and cells of the liver and the pancreas. Cells can be obtained from cell-line cultures, biopsies, and tissue banks. Genes, molecules, or nucleic acids that secrete factors that influence the growth of cells, the production of extracellular matrix material, and other cell functions can be inserted in cells by any of a variety of standard transfection techniques.

  12. Isoprene emissions from downy oak under water limitation during an entire growing season: what cost for growth?

    Directory of Open Access Journals (Sweden)

    Anne-Cyrielle Genard-Zielinski

    Full Text Available Increases in the production of terpene- and phenolic-like compounds in plant species under abiotic stress conditions have been interpreted in physiological studies as a supplementary defense system due to their capacity to limit cell oxidation. From an ecological perspective however, these increases are only expected to confer competitive advantages if they do not imply a significant cost for the plant, that is, growth reduction. We investigated shifts of isoprene emissions, and to a lesser extent phenolic compound concentration, of Quercus pubescens Willd. from early leaf development to leaf senescence under optimal watering (control: C, mild and severe water stress (MS, SS. The impact of water stress was concomitantly assessed on plant physiological (chlorophyll fluorescence, stomatal conductance, net photosynthesis, water potential functional (relative leaf water content, leaf mass per area ratio and growth (aerial and root biomass traits. Growth changes allowed to estimate the eventual costs related to the production of isoprene and phenolics. The total phenolic content was not modified under water stress whereas isoprene emissions were promoted under MS over the entire growing cycle despite the decline of Pn by 35%. Under SS, isoprene emissions remained similar to C all over the study despite the decline of Pn by 47% and were thereby clearly uncoupled to Pn leading to an overestimation of the isoprene emission factor by 44%. Under SS, maintenance of isoprene emissions and phenolic compound concentration resulted in very significant costs for the plants as growth rates were very significantly reduced. Under MS, increases of isoprene emission and maintenance of phenolic compound concentration resulted in moderate growth reduction. Hence, it is likely that investment in isoprene emissions confers Q. pubescens an important competitive advantage during moderate but not severe periods of water scarcity. Consequences of this response for air

  13. Isoprene emissions from downy oak under water limitation during an entire growing season: what cost for growth?

    Science.gov (United States)

    Genard-Zielinski, Anne-Cyrielle; Ormeño, Elena; Boissard, Christophe; Fernandez, Catherine

    2014-01-01

    Increases in the production of terpene- and phenolic-like compounds in plant species under abiotic stress conditions have been interpreted in physiological studies as a supplementary defense system due to their capacity to limit cell oxidation. From an ecological perspective however, these increases are only expected to confer competitive advantages if they do not imply a significant cost for the plant, that is, growth reduction. We investigated shifts of isoprene emissions, and to a lesser extent phenolic compound concentration, of Quercus pubescens Willd. from early leaf development to leaf senescence under optimal watering (control: C), mild and severe water stress (MS, SS). The impact of water stress was concomitantly assessed on plant physiological (chlorophyll fluorescence, stomatal conductance, net photosynthesis, water potential) functional (relative leaf water content, leaf mass per area ratio) and growth (aerial and root biomass) traits. Growth changes allowed to estimate the eventual costs related to the production of isoprene and phenolics. The total phenolic content was not modified under water stress whereas isoprene emissions were promoted under MS over the entire growing cycle despite the decline of Pn by 35%. Under SS, isoprene emissions remained similar to C all over the study despite the decline of Pn by 47% and were thereby clearly uncoupled to Pn leading to an overestimation of the isoprene emission factor by 44%. Under SS, maintenance of isoprene emissions and phenolic compound concentration resulted in very significant costs for the plants as growth rates were very significantly reduced. Under MS, increases of isoprene emission and maintenance of phenolic compound concentration resulted in moderate growth reduction. Hence, it is likely that investment in isoprene emissions confers Q. pubescens an important competitive advantage during moderate but not severe periods of water scarcity. Consequences of this response for air quality in North

  14. Platelet-derived growth factor-B normalizes micromorphology and vessel function in vascular endothelial growth factor-A-induced squamous cell carcinomas.

    Science.gov (United States)

    Lederle, Wiltrud; Linde, Nina; Heusel, Julia; Bzyl, Jessica; Woenne, Eva C; Zwick, Stefan; Skobe, Mihaela; Kiessling, Fabian; Fusenig, Norbert E; Mueller, Margareta M

    2010-02-01

    Vascular endothelial growth factor (VEGF), which is a key regulator of angiogenesis, often induces formation of immature vessels with increased permeability and reduced vessel functionality. Here, we demonstrate that de novo expression of murine (m)VEGF-164 induces malignant and invasive tumor growth of HaCaT keratinocytes. However, the mVEGF-164-induced tumors are ulcerated with a disorganized epithelium that is interrupted by lacunae with limited basement membrane and endothelial cell coverage. Vessel maturation is strongly impaired. Tumor and vessel micromorphology are markedly improved by the combined expression of human platelet-derived growth factor (hPDGF)-B and mVEGF-164. Although tumor size and malignancy are comparable with either mVEGF-164 alone or combined human PDGF-B and mVEGF-164 expression, combined hPDGF-B and mVEGF-164 expression leads to a more solid and compact tumor tissue with a mature functional tumor vasculature and a higher microvessel density, as demonstrated histologically and by dynamic contrast-enhanced magnetic resonance imaging. Treatment of the hPDGF-B- and mVEGF-164-expressing tumors with imatinib mesylate to block PDGF-B signaling reverses this effect. In addition, tumor cell invasion of mVEGF-164 transfectants and mVEGF-164 plus hPDGF-B transfectants in vivo is associated with a marked induction of tumor-derived matrix metalloproteinase-1 and stromal matrix metalloproteinase-9 and -13, as was confirmed in three-dimensional organotypic co-cultures with fibroblasts in vitro. These data clearly demonstrate the need for a concerted action of different growth factors in the establishment of solid tumors with functional vasculature and emphasize the need for a multifactorial therapy.

  15. Stochastic Heat Equation Limit of a (2 + 1)d Growth Model

    Science.gov (United States)

    Borodin, Alexei; Corwin, Ivan; Toninelli, Fabio Lucio

    2017-03-01

    We determine a {q to 1} limit of the two-dimensional q-Whittaker driven particle system on the torus studied previously in Corwin and Toninelli (Electron. Commun. Probab. 21(44):1-12, 2016). This has an interpretation as a (2 + 1)-dimensional stochastic interface growth model, which is believed to belong to the so-called anisotropic Kardar-Parisi-Zhang (KPZ) class. This limit falls into a general class of two-dimensional systems of driven linear SDEs which have stationary measures on gradients. Taking the number of particles to infinity we demonstrate Gaussian free field type fluctuations for the stationary measure. Considering the temporal evolution of the stationary measure, we determine that along characteristics, correlations are asymptotically given by those of the (2 + 1)-dimensional additive stochastic heat equation. This confirms (for this model) the prediction that the non-linearity for the anisotropic KPZ equation in (2 + 1)-dimension is irrelevant.

  16. Stochastic Heat Equation Limit of a (2 + 1)d Growth Model

    Science.gov (United States)

    Borodin, Alexei; Corwin, Ivan; Toninelli, Fabio Lucio

    2016-07-01

    We determine a {q to 1} limit of the two-dimensional q-Whittaker driven particle system on the torus studied previously in Corwin and Toninelli (Electron. Commun. Probab. 21(44):1-12, 2016). This has an interpretation as a (2 + 1)-dimensional stochastic interface growth model, which is believed to belong to the so-called anisotropic Kardar-Parisi-Zhang (KPZ) class. This limit falls into a general class of two-dimensional systems of driven linear SDEs which have stationary measures on gradients. Taking the number of particles to infinity we demonstrate Gaussian free field type fluctuations for the stationary measure. Considering the temporal evolution of the stationary measure, we determine that along characteristics, correlations are asymptotically given by those of the (2 + 1)-dimensional additive stochastic heat equation. This confirms (for this model) the prediction that the non-linearity for the anisotropic KPZ equation in (2 + 1)-dimension is irrelevant.

  17. Stochastic contribution to the growth factor in the LCDM model

    Energy Technology Data Exchange (ETDEWEB)

    Ribeiro, A. L.B.; Andrade, A. P.A.; Letelier, P. S.

    2009-01-01

    We study the effect of noise on the evolution of the growth factor of density perturbations in the context of the LCDM model. Stochasticity is introduced as a Wiener process amplified by an intensity parameter alpha. By comparing the evolution of deterministic and stochastic cases for different values of alpha we estimate the intensity level necessary to make noise relevant for cosmological tests based on large-scale structure data. Our results indicate that the presence of random forces underlying the fluid description can lead to significant deviations from the nonstochastic solution at late times for alpha>0.001.

  18. Nerve growth factor and injured peripheral nerve regeneration

    Institute of Scientific and Technical Information of China (English)

    Endong Shi; Bingchen Wang; Qingshan Sun

    2008-01-01

    Nerve growth factor (NGF) exhibits many biological activities, such as supply of nutrients, neuroprotection, and the generation and rehabilitation of injured nerves. The neuroprotective and neurotrophic qualities of NGF are generally recognized. NGF may enhance axonal regeneration and myelination of peripheral nerves, as well as cooperatively promote functional recovery of injured nerves and limbs. The clinical efficacy of NGF and its therapeutic potentials are reviewed here. This paper also reviews the latest NGF research developments for repairing injured peripheral nerve, thereby providing scientific evidence for the appropriate clinical application of NGF.

  19. Insulin infusion reduces hepatocyte growth factor in lean humans

    DEFF Research Database (Denmark)

    de Courten, Barbora; de Courten, Maximilian; Dougherty, Sonia;

    2013-01-01

    OBJECTIVE: Plasma Hepatocyte Growth Factor (HGF) is significantly elevated in obesity and may contribute to vascular disease, metabolic syndrome or cancer in obese individuals. The current studies were done to determine if hyperinsulinemia increases plasma HGF. MATERIALS/METHODS: Twenty......-two participants (10 women/12 men, BMI 20.6-34.5 kg/m(2), age 18-49 years) underwent a hyperinsulinemic euglycemic clamp with measurement of HGF at baseline and steady state. Relationships between baseline HGF, anthropometrics, triglycerides, liver enzymes, c-reactive protein and adiponectin were also evaluated...

  20. Targeting the epidermal growth factor receptor in solid tumor malignancies

    DEFF Research Database (Denmark)

    Nedergaard, Mette K; Hedegaard, Chris J; Poulsen, Hans S

    2012-01-01

    The epidermal growth factor receptor (EGFR) is over-expressed, as well as mutated, in many types of cancers. In particular, the EGFR variant type III mutant (EGFRvIII) has attracted much attention as it is frequently and exclusively found on many tumor cells, and hence both EGFR and EGFRvIII have...... been proposed as valid targets in many cancer therapy settings. Different strategies have been developed in order to either inhibit EGFR/EGFRvIII activity or to ablate EGFR/EGFRvIII-positive tumor cells. Drugs that inhibit these receptors include monoclonal antibodies (mAbs) that bind...

  1. Therapeutic potential of growth factors in pulmonary emphysematous condition.

    Science.gov (United States)

    Muyal, Jai Prakash; Muyal, Vandana; Kotnala, Sudhir; Kumar, Dhananjay; Bhardwaj, Harsh

    2013-04-01

    Pulmonary emphysema is a major manifestation of chronic obstructive pulmonary disease (COPD), which is characterized by progressive destruction of alveolar parenchyma with persistent inflammation of the small airways. Such destruction in the distal respiratory tract is irreversible and irreparable. All-trans-retinoic acid was suggested as a novel therapy for regeneration of lost alveoli in emphysema. However, profound discrepancies were evident between studies. At present, no effective therapeutic options are available that allow for the regeneration of lost alveoli in emphysematous human lungs. Recently, some reports on rodent's models have suggested the beneficial effects of various growth factors toward alveolar maintenance and repair processes.

  2. Immunohistochemical localization of epidermal growth factor in rat and man

    DEFF Research Database (Denmark)

    Poulsen, Steen Seier; Nexø, Ebba

    1986-01-01

    Epidermal growth factor (EGF) is a peptide which stimulates cell mitotic activity and differentiation, has a cytoprotective effect on the gastroduodenal mucosa, and inhibits gastric acid secretion. The immunohistochemical localization of EGF in the Brunner's glands and the submandibular glands...... is well documented. The localization of EGF in other tissues is still unclarified. In the present study, the immunohistochemical localization of EGF in tissues from rat, man and a 20 week human fetus were investigated. In man and rat, immunoreaction was found in the submandibular glands, the serous glands...

  3. Cardiac Regeneration using Growth Factors: Advances and Challenges.

    Science.gov (United States)

    Rebouças, Juliana de Souza; Santos-Magalhães, Nereide Stela; Formiga, Fabio Rocha

    2016-09-01

    Myocardial infarction is the most significant manifestation of ischemic heart disease and is associated with high morbidity and mortality. Novel strategies targeting at regenerating the injured myocardium have been investigated, including gene therapy, cell therapy, and the use of growth factors. Growth factor therapy has aroused interest in cardiovascular medicine because of the regeneration mechanisms induced by these biomolecules, including angiogenesis, extracellular matrix remodeling, cardiomyocyte proliferation, stem-cell recruitment, and others. Together, these mechanisms promote myocardial repair and improvement of the cardiac function. This review aims to address the strategic role of growth factor therapy in cardiac regeneration, considering its innovative and multifactorial character in myocardial repair after ischemic injury. Different issues will be discussed, with emphasis on the regeneration mechanisms as a potential therapeutic resource mediated by growth factors, and the challenges to make these proteins therapeutically viable in the field of cardiology and regenerative medicine. Resumo O infarto do miocárdio representa a manifestação mais significativa da cardiopatia isquêmica e está associado a elevada morbimortalidade. Novas estratégias vêm sendo investigadas com o intuito de regenerar o miocárdio lesionado, incluindo a terapia gênica, a terapia celular e a utilização de fatores de crescimento. A terapia com fatores de crescimento despertou interesse em medicina cardiovascular, devido aos mecanismos de regeneração induzidos por essas biomoléculas, incluindo angiogênese, remodelamento da matriz extracelular, proliferação de cardiomiócitos e recrutamento de células-tronco, dentre outros. Em conjunto, tais mecanismos promovem a reparação do miocárdio e a melhora da função cardíaca. Esta revisão pretende abordar o papel estratégico da terapia, com fatores de crescimento, para a regeneração cardíaca, considerando seu car

  4. Fibroblast growth factor-2 and vascular endothelial growth factor mediated augmentation of angiogenesis and bone formation in vascularized bone allotransplants.

    Science.gov (United States)

    Larsen, Mikko; Willems, Wouter F; Pelzer, Michael; Friedrich, Patricia F; Dadsetan, Mahrokh; Bishop, Allen T

    2014-05-01

    We previously demonstrated recipient-derived neoangiogenesis to maintain viability of living bone allogeneic transplants without long-term immunosuppression. The effect of cytokine delivery to enhance this process is studied. Vascularized femur transplantation was performed from Dark Agouti to Piebald Virol Glaxo rats. Poly(d,l-lactide-co-glycolide) microspheres loaded with buffer (N = 11), basic fibroblast growth factor (FGF2) (N = 10), vascular endothelial growth factor (VEGF) (N = 11), or both (N = 11) were inserted intramedullarly alongside a recipient-derived arteriovenous bundle. FK-506 was administered for 2 weeks. At 18 weeks, bone blood flow, microangiography, histologic, histomorphometric, and alkaline phosphatase measurements were performed. Bone blood flow was greater in the combined group than control and VEGF groups (P = 0.04). Capillary density was greater in the FGF2 group than in the VEGF and combined groups (P Bone viability, growth, and alkaline phosphatase activity did not vary significantly between groups. Neoangiogenesis in vascularized bone allotransplants is enhanced by angiogenic cytokine delivery, with results using FGF2 that are comparable to isotransplant from previous studies. Further studies are needed to achieve bone formation similar to isotransplants. Copyright © 2013 Wiley Periodicals, Inc.

  5. Potential role of growth factors with particular focus on growth hormone and insulin-like growth factor-1 in the management of chronic kidney disease

    DEFF Research Database (Denmark)

    Feldt-Rasmussen, Bo; El Nahas, Meguid

    2009-01-01

    on growth factors and, in particular, on the role of growth hormone (GH) and insulin-like growth factor-1 (IGF-1) in the treatment of CKD and the management of its complications. Disturbances of the GH-IGF-1 axis in CKD have suggested therapeutic roles for both the inhibition, as well as the stimulation...... administration on the nutritional parameters of patients on renal replacement therapy. More recently, a larger randomized, double-blind, placebo-controlled, 26-week, proof-of-concept clinical study was conducted to investigate the effect of GH (Norditropin; Novo Nordisk, Bagsvaerd, Denmark) in adult chronic......Prevention and treatment of chronic kidney disease (CKD) so far primarily has been based on early and aggressive treatment of hypertension. A number of other therapeutic approaches have the potential of being translated to the clinical area within the foreseeable future. In this review, we focus...

  6. Vascular endothelial growth factor A and vascular endothelial growth factor receptor 2 expression in non-small cell lung cancer patients: relation to prognosis

    DEFF Research Database (Denmark)

    Bonnesen, Barbara; Pappot, Helle; Holmstav, Julie;

    2009-01-01

    elements in neoplastic cells and their microenvironment have recently been and are continuously developed including drugs inhibiting the angiogenic system. Angiogenic factor vascular endothelial growth factor (VEGF) and its receptor vascular endothelial growth factor receptor 2 (VEGFR2) seem to play key...

  7. Dynamic root growth and architecture responses to limiting nutrient availability: linking physiological models and experimentation.

    Science.gov (United States)

    Postma, Johannes A; Schurr, Ulrich; Fiorani, Fabio

    2014-01-01

    In recent years the study of root phenotypic plasticity in response to sub-optimal environmental factors and the genetic control of these responses have received renewed attention. As a path to increased productivity, in particular for low fertility soils, several applied research projects worldwide target the improvement of crop root traits both in plant breeding and biotechnology contexts. To assist these tasks and address the challenge of optimizing root growth and architecture for enhanced mineral resource use, the development of realistic simulation models is of great importance. We review this research field from a modeling perspective focusing particularly on nutrient acquisition strategies for crop production on low nitrogen and low phosphorous soils. Soil heterogeneity and the dynamics of nutrient availability in the soil pose a challenging environment in which plants have to forage efficiently for nutrients in order to maintain their internal nutrient homeostasis throughout their life cycle. Mathematical models assist in understanding plant growth strategies and associated root phenes that have potential to be tested and introduced in physiological breeding programs. At the same time, we stress that it is necessary to carefully consider model assumptions and development from a whole plant-resource allocation perspective and to introduce or refine modules simulating explicitly root growth and architecture dynamics through ontogeny with reference to key factors that constrain root growth. In this view it is important to understand negative feedbacks such as plant-plant competition. We conclude by briefly touching on available and developing technologies for quantitative root phenotyping from lab to field, from quantification of partial root profiles in the field to 3D reconstruction of whole root systems. Finally, we discuss how these approaches can and should be tightly linked to modeling to explore the root phenome.

  8. Transforming growth factor-β and abdominal aortic aneurysms.

    Science.gov (United States)

    Wang, Yutang; Krishna, Smriti; Walker, Philip J; Norman, Paul; Golledge, Jonathan

    2013-01-01

    Abdominal aortic aneurysms (AAAs) are common problems in aged people which can be associated with severe complications including aortic rupture and death. Transforming growth factor-β (TGFβ) has been implicated as causative in the development of thoracic aortic aneurysms (TAAs). In contrast, current evidence suggests TGFβ inhibits AAA development. Polymorphisms in the TGFβ signaling components are associated with AAA in some human population studies. In experimental animals TGFβ protects against AAA formation, progression and rupture. In animal models of AAA TGFβ decreases aortic inflammatory cell infiltration, extracellular matrix degradation, and vascular smooth muscle cell apoptosis, all factors implicated in AAA pathogenesis. The TGFβ signaling pathway may provide a therapeutic target for AAA although better clarity is needed regarding the distinct roles of TGFβ in TAA and AAA.

  9. Recombinant expression of placental growth factor in baculovirus expression system

    Directory of Open Access Journals (Sweden)

    Narges Arbabi

    2016-12-01

    Full Text Available Background: Angiogenesis or formation of new blood vessels is the most important factor in physiological and pathological conditions. Human Placental growth factor (hPLGF protein in is one of the most important proteins which stimulate angiogenesis. Baculovirus expression system has been used successfully to over express eukaryotic proteins in insect cells. This system uses a very strong viral promoter, AcNPV polyhedrin, for high level of protein expression. Methods: hPLGF gene cloned in pFastBac-HT vector and transformed in DH10Bac.The recombinant bacmid was extracted and used in SF9 insect cells and transfected by cellfectin method. Target protein expression was confirmed with Western blot. Results: Transferring of the recombinant vector into Bacmid was successful and the PLGF gene sequence was confirmed. PLGF and recombinant protein expression by Western blotting was confirmed. Conclusion: Baculovirus protein expression system expresses PLGF strongly and recombinant protein can be used in different tests.

  10. Expression of vascular endothelial growth factor in malignant mesothelioma.

    Science.gov (United States)

    Aoe, Keisuke; Hiraki, Akio; Tanaka, Takehiro; Gemba, Ken-Ichi; Taguchi, Koji; Murakami, Tomoyuki; Sueoka, Naoko; Kamei, Toshiaki; Ueoka, Hiroshi; Sugi, Kazuro; Yoshino, Tadashi; Kishimoto, Takumi

    2006-01-01

    Malignant mesothelioma is the most common primary pleural neoplasm. Angiogenesis is an important component of a variety of pathological processes, including carcinogenesis and tumor metastases. Vascular endothelial growth factor (VEGF) is the most potent known endothelial, cell specific mitogen. The authors assessed the relation between VEGF expression and clinicopathological variables or overall survival, in malignant mesothelioma. We studied 37 patients with malignant pleural mesothelioma and found that 36 out of 37 (97.3%) malignant mesothelioma samples were stained positively for VEGF. An increased expression of VEGF was observed in the epithelioid type compared with the other histological types of malignant mesothelioma, including the biphasic and sarcomatoid types. No statistically significant association was observed between VEGF expression and gender, age, or clinical stage. Furthermore, the expression of VEGF did not impact on the survival of patients with malignant mesothelioma. Although VEGF expression might be important for tumor development and maintenance, it was not identified as a prognostic factor in malignant mesothelioma.

  11. Hepatocyte growth factor in lung repair and pulmonary fibrosis

    Institute of Scientific and Technical Information of China (English)

    Ronald Allan M PANGANIBAN; Regina M DAY

    2011-01-01

    Pulmonary remodeling is characterized by the permanent and progressive loss of the normal alveolar architecture, especially the loss of alveolar epithelial and endothelial cells, persistent proliferation of activated fibroblasts, or myoflbroblasts, and alteration of extracellular matrix. Hepatocyte growth factor (HGF) is a pleiotropic factor, which induces cellular motility, survival, proliferation, and morphogenesis, depending upon the cell type. In the adult, HGF has been demonstrated to play a critical role in tissue repair, including in the lung. Administration of HGF protein or ectopic expression of HGF has been demonstrated in animal models of pulmonary fibrosis to induce normal tissue repair and to prevent fibrotic remodeling. HGF-induced inhibition of fibrotic remodeling may occur via multiple direct and indirect mechanisms including the induction of cell survival and proliferation of pulmonary epithelial and endothelial cells, and the reduction of myofibroblast accumulation.

  12. Growth potential limits drought morphological plasticity in seedlings from six Eucalyptus provenances.

    Science.gov (United States)

    Maseda, Pablo H; Fernández, Roberto J

    2016-02-01

    Water stress modifies plant above- vs belowground biomass allocation, i.e., morphological plasticity. It is known that all species and genotypes reduce their growth rate in response to stress, but in the case of water stress it is unclear whether the magnitude of such reduction is linked to the genotype's growth potential, and whether the reduction can be largely attributed to morphological adjustments such as plant allocation and leaf and root anatomy. We subjected seedlings of six seed sources, three from each of Eucalyptus camaldulensis (potentially fast growing) and E. globulus (inherently slow growing), to three experimental water regimes. Biomass, leaf area and root length were measured in a 6-month glasshouse experiment. We then performed functional growth analysis of relative growth rate (RGR), and aboveground (leaf area ratio (LAR), specific leaf area (SLA) and leaf mass ratio (LMR)) and belowground (root length ratio (RLR), specific root length (SRL) and root mass ratio (RMR)) morphological components. Total biomass, root biomass and leaf area were reduced for all Eucalyptus provenances according to drought intensity. All populations exhibited drought plasticity, while those of greater growth potential (RGRmax) had a larger reduction in growth (discounting the effect of size). A positive correlation was observed between drought sensitivity and RGRmax. Aboveground, drought reduced LAR and LMR; under severe drought a negative correlation was found between LMR and RGRmax. Belowground, drought reduced SRL but increased RMR, resulting in no change in RLR. Under severe drought, a negative correlation was found between RLR, SRL and RGRmax. Our evidence strongly supports the classic ecophysiological trade-off between growth potential and drought tolerance for woody seedlings. It also suggests that slow growers would have a low capacity to adjust their morphology. For shoots, this constraint on plasticity was best observed in partition (i.e., LMR) whereas for

  13. Plant growth enhancement by elevated CO2 eliminated by joint water and nitrogen limitation

    Science.gov (United States)

    Reich, Peter B.; Hobbie, Sarah E.; Lee, Tali D.

    2014-12-01

    Rising atmospheric CO2 concentrations can fertilize plant growth. The resulting increased plant uptake of CO2 could, in turn, slow increases in atmospheric CO2 levels and associated climate warming. CO2 fertilization effects may be enhanced when water availability is low, because elevated CO2 also leads to improved plant water-use efficiency. However, CO2 fertilization effects may be weaker when plant growth is limited by nutrient availability. How variation in soil nutrients and water may act together to influence CO2 fertilization is unresolved. Here we report plant biomass levels from a five-year, open-air experiment in a perennial grassland under two contrasting levels of atmospheric CO2, soil nitrogen and summer rainfall, respectively. We find that the presence of a CO2 fertilization effect depends on the amount of available nitrogen and water. Specifically, elevated CO2 levels led to an increase in plant biomass of more than 33% when summer rainfall, nitrogen supply, or both were at the higher levels (ambient for rainfall and elevated for soil nitrogen). But elevated CO2 concentrations did not increase plant biomass when both rainfall and nitrogen were at their lower level. We conclude that given widespread, simultaneous limitation by water and nutrients, large stimulation of biomass by rising atmospheric CO2 concentrations may not be ubiquitous.

  14. Avoiding the Limits to Growth: Gross National Happiness in Bhutan as a Model for Sustainable Development

    Directory of Open Access Journals (Sweden)

    Jeremy S. Brooks

    2013-08-01

    Full Text Available In their 30-year update to Limits to Growth, Meadows et al. call for a vision of sustainable development that includes systemic change brought on by new perspectives on the purpose of development, new ways of measuring progress, and changes in social norms. Here, I discuss Meadows et al.’s work in the context of the literature on sustainable development and well-being as well as the development trajectory of Bhutan. I suggest that Bhutan’s development approach mirrors Meadows et al.’s recommendations and provides one model for sustainable development. The ideal of maximizing Gross National Happiness (GNH exemplifies Bhutan’s commitment to holistic development and dovetails with arguments about the shortcomings of approaches that emphasize economic growth. I provide examples of how GNH has been put into practice, describe how happiness is being measured, and discuss the emergence of social norms and a shared Bhutanese identity that may contribute to sustainable development. Bhutan’s development success suggests that an alternative to growth-centric development is viable. However, while Bhutan’s standard of living has increased, the country faces challenges, the most important of which may be their ability to manage rising consumption levels. Importantly, other nations have begun measuring well-being and considering similar development approaches.

  15. Sulfur amino acid metabolism limits the growth of children living in environments of poor sanitation.

    Science.gov (United States)

    Bickler, Stephen W; Ring, Jason; De Maio, Antonio

    2011-09-01

    Environmental enteropathy has been identified as a cause of poor growth in children living in low-income countries, but a mechanism has not been well defined. We suggest changes in sulfur amino acid metabolism can in part explain the poor growth and possibly the histological changes in the small bowel, which is the hallmark of environmental enteropathy. In environments of poor sanitation, where infection is common, we propose increased oxidative stress drives methionine metabolism toward cystathionine synthesis. This "cystathionine siphon" limits sulfur amino acids from participating in critical protein synthesis pathways. Increased expression of cystathionine β-synthase (CBS) could be one mechanism, as lipopolysaccharide and TNFα increase activity of this enzyme in vivo. CBS catalyzes the first of two steps in the transsulfuration pathway that converts homocysteine to cysteine. As enterocytes are one of the most rapidly proliferating cells in the body, we suggest diminished translation might also be important in the barrier failure observed in environmental enteropathy. Identifying sulfur amino acid metabolism as a mechanism leading to poor growth provides a new testable hypothesis for the undernutrition observed in children living in settings of poor sanitation.

  16. Limited by sensing - A minimal stochastic model of the lag-phase during diauxic growth.

    Science.gov (United States)

    Chu, Dominique

    2017-02-07

    Many microbes when grown on a mixture of two carbon sources utilise first and exclusively the preferred sugar, before switching to the less preferred carbon source. This results in two distinct exponential growth phases, often interrupted by a lag-phase of reduced growth termed the lag-phase. While the lag-phase appears to be an evolved feature, it is not clear what drives its evolution, as it comes with a substantial up-front fitness penalty due to lost growth. In this article a minimal mathematical model based on a master-equation approach is proposed. This model can explain many empirically observed phenomena. It suggests that the lag-phase can be understood as a manifestation of the trade-off between switching speed and switching efficiency. Moreover, the model predicts heterogeneity of the population during the lag-phase. Finally, it is shown that the switch from one carbon source to another one is a sensing problem and the lag-phase is a manifestation of known fundamental limitations of biological sensors.

  17. Decreased expression of serum and microvascular vascular endothelial growth factor receptor-2 in meningococcal sepsis*.

    NARCIS (Netherlands)

    Flier, M. van der; Baerveldt, E.M.; Miedema, A.; Hartwig, N.G.; Hazelzet, J.A.; Emonts, M.; Groot, R. de; Prens, E.P.; Vught, A.J. van; Jansen, N.J.

    2013-01-01

    OBJECTIVES: To determine the skin microvessel expression of vascular endothelial growth factor receptor 2 and serum-soluble vascular endothelial growth factor receptor 2 levels in children with meningococcal sepsis. DESIGN: Observational study. SETTING: Two tertiary academic children hospital PICUs.

  18. Compound list: transforming growth factor beta 1 [Open TG-GATEs

    Lifescience Database Archive (English)

    Full Text Available transforming growth factor beta 1 TGFB1 00182 ftp://ftp.biosciencedbc.jp/archive/op...en-tggates/LATEST/Human/in_vitro/transforming_growth_factor_beta_1.Human.in_vitro.Liver.zip ...

  19. Effect of transforming growth factor-β1 on human intrahepatic cholangiocarcinoma cell growth

    Institute of Scientific and Technical Information of China (English)

    Tetsuya Shimizu; Takashi Tajiri; Shigeki Yokomuro; Yoshiaki Mizuguchi; Yutaka Kawahigashi; Yasuo Arima; Nobuhiko Taniai; Yasuhiro Mamada; Hiroshi Yoshida; Koho Akimaru

    2006-01-01

    AIM: To elucidate the biological effects of transforming growth factor-β1 (TGF-β1) on intrahepatic cholangiocarcinoma (ICC).METHODS: We investigated the effects of TGF-β1 on human ICC cell lines (HuCCT1, MEC, and HuH-28) by monitoring the influence of TGF-β1 on tumor growth and interleukin-6 (IL-6) expression in ICC cells.RESULTS: All three human ICC cell lines produced TGF-β1 and demonstrated accelerated growth in the presence of TGF-β1 with no apoptotic effect. Studies on HuCCT1 revealed a TGF-β1-induced stimulation of the expression of TGF-β1, as well as a decrease in TGF-β1 mRNA expression induced by neutralizing anti-TGF-β1 antibody. These results indicate that TGF-β1 stimulates the production and function of TGF-β1 in an autocrine fashion. Further, IL-6 secretion was observed in all three cell lines and exhibited an inhibitory response to neutralizing anti-TGF-β1 antibody. Experiments using HuCCT1 revealed a TGF-β1-induced acceleration of IL-6 protein expression and mRNA levels. These findings demonstrate a functional interaction between TGF-β1 and IL-6. All three cell lines proliferated in the presence of IL-6. In contrast, TGF-β1 induced no growth effect in HuCCT1 in the presence of small interfering RNA against a specific cell surface receptor of IL-6 and signal transducer and activator of transcription-3.CONCLUSION: ICC cells produce TGF-β1 and confer a TGF-β1-induced growth effect in an autocrine fashion.TGF-β1 activates IL-6 production, and the functional interaction between TGF-β1 and IL-6 contributes to ICC cell growth by TGF-β1.

  20. Transgenic Soybean Production of Bioactive Human Epidermal Growth Factor (EGF.

    Directory of Open Access Journals (Sweden)

    Yonghua He

    Full Text Available Necrotizing enterocolitis (NEC is a devastating condition of premature infants that results from the gut microbiome invading immature intestinal tissues. This results in a life-threatening disease that is frequently treated with the surgical removal of diseased and dead tissues. Epidermal growth factor (EGF, typically found in bodily fluids, such as amniotic fluid, salvia and mother's breast milk, is an intestinotrophic growth factor and may reduce the onset of NEC in premature infants. We have produced human EGF in soybean seeds to levels biologically relevant and demonstrated its comparable activity to commercially available EGF. Transgenic soybean seeds expressing a seed-specific codon optimized gene encoding of the human EGF protein with an added ER signal tag at the N' terminal were produced. Seven independent lines were grown to homozygous and found to accumulate a range of 6.7 +/- 3.1 to 129.0 +/- 36.7 μg EGF/g of dry soybean seed. Proteomic and immunoblot analysis indicates that the inserted EGF is the same as the human EGF protein. Phosphorylation and immunohistochemical assays on the EGF receptor in HeLa cells indicate the EGF protein produced in soybean seed is bioactive and comparable to commercially available human EGF. This work demonstrates the feasibility of using soybean seeds as a biofactory to produce therapeutic agents in a soymilk delivery platform.