WorldWideScience

Sample records for growth factor-i responses

  1. Insulin-like growth factor-I gene delivery to astrocytes reduces their inflammatory response to lipopolysaccharide

    Directory of Open Access Journals (Sweden)

    Goya Rodolfo G

    2011-03-01

    Full Text Available Abstract Background Insulin-like growth factor-I (IGF-I exerts neuroprotective actions in the central nervous system that are mediated at least in part by control of activation of astrocytes. In this study we have assessed the efficacy of exogenous IGF-I and IGF-I gene therapy in reducing the inflammatory response of astrocytes from cerebral cortex. Methods An adenoviral vector harboring the rat IGF-I gene and a control adenoviral vector harboring a hybrid gene encoding the herpes simplex virus type 1 thymidine kinase fused to Aequorea victoria enhanced green fluorescent protein were used in this study. Primary astrocytes from mice cerebral cortex were incubated for 24 h or 72 h with vehicle, IGF-I, the IGF-I adenoviral vector, or control vector; and exposed to bacterial lipopolysaccharide to induce an inflammatory response. IGF-I levels were measured by radioimmunoassay. Levels of interleukin 6, tumor necrosis factor-α, interleukin-1β and toll-like receptor 4 mRNA were assessed by quantitative real-time polymerase chain reaction. Levels of IGF-I receptor and IGF binding proteins 2 and 3 were assessed by western blotting. The subcellular distribution of nuclear factor κB (p65 was assessed by immunocytochemistry. Statistical significance was assessed by one way analysis of variance followed by the Bonferroni pot hoc test. Results IGF-I gene therapy increased IGF-I levels without affecting IGF-I receptors or IGF binding proteins. Exogenous IGF-I, and IGF-I gene therapy, decreased expression of toll-like receptor 4 and counteracted the lipopolysaccharide-induced inflammatory response of astrocytes. In addition, IGF-I gene therapy decreased lipopolysaccharide-induced translocation of nuclear factor κB (p65 to the cell nucleus. Conclusion These findings demonstrate efficacy of exogenous IGF-I and of IGF-I gene therapy in reducing the inflammatory response of astrocytes. IGF-I gene therapy may represent a new approach to reduce inflammatory

  2. Increase in tendon protein synthesis in response to insulin-like growth factor-I is preserved in elderly men

    DEFF Research Database (Denmark)

    Nielsen, Rie Harboe; Holm, Lars; Malmgaard-Clausen, Nikolaj Mølkjær

    2014-01-01

    Insulin-like growth factor-I (IGF-I) is known to be an anabolic factor in tendon, and the systemic levels are reduced with aging. However, it is uncertain how tendon fibroblasts are involved in tendon aging and how aging cells respond to IGF-I. The purpose of this study was to investigate...... the in vivo IGF-I stimulation of tendon protein synthesis in elderly compared with young men. We injected IGF-I in the patellar tendons of young (n = 11, 20-30 yr of age) and old (n = 11, 66-75 yr of age) men, and the acute fractional synthesis rate (FSR) of tendon protein was measured with the stable isotope...... technique and compared with the contralateral side (injected with saline as control). We found that tendons injected with IGF-I had significantly higher protein FSR compared with controls (old group: 0.018 ± 0.015 vs. 0.008 ± 0.008, young group: 0.016 ± 0.009 vs. 0.009 ± 0.006%/h, mean ± SE, P

  3. Insulin-like growth factor I and glucagon-like peptide-2 responses to fasting followed by controlled or ad libitum refeeding in rats

    DEFF Research Database (Denmark)

    Nelson, David W; Murali, Sangita G; Liu, Xiaowen

    2008-01-01

    Luminal nutrients stimulate structural and functional regeneration in the intestine through mechanisms thought to involve insulin-like growth factor I (IGF-I) and glucagon-like peptide-2 (GLP-2). We investigated the relationship between IGF-I and GLP-2 responses and mucosal growth in rats fasted...... for 48 h and then refed for 2 or 4 days by continuous intravenous or intragastric infusion or ad libitum feeding. Fasting induced significant decreases in body weight, plasma concentrations of IGF-I and bioactive GLP-2, jejunal mucosal cellularity (mass, protein, DNA, and villus height), IGF-I m...

  4. Insulin-like growth factor I (IGF-I) and IGF-binding protein 3 response to growth hormone is impaired in HIV-infected children.

    Science.gov (United States)

    Rondanelli, Mariangela; Caselli, Desiree; Aricò, Maurizio; Maccabruni, Anna; Magnani, Barbara; Bacchella, Luisa; De Stefano, Anna; Maghnie, Mohamed; Solerte, Sebastiano Bruno; Minoli, Lorenzo

    2002-03-20

    To better characterize the somatotropic axis in HIV-infected children the circadian rhythm of growth hormone (GH), and basal and stimulated (by an insulin-like growth factor I [IGF-I] generation test) plasma levels of IGF-I and insulin-like growth factor-binding protein 3 (IGFBP-3), were evaluated in 16 children (9 boys and 7 girls; age range, 7-11 years) with HIV infection. All patients were free from active opportunistic infection or liver disease at the time of the study. Sixteen age- and sex-matched healthy children (10 boys and 6 girls; age range, 7-11 years) served as control subjects. GH rhythmometric data were analyzed by single and population mean cosinor analysis. As regards the IGF-I generation test, biosynthetic human GH (hGH, 0.1 IU/kg, 0.033 mg/kg) was administered subcutaneously for 4 days and blood samples were taken from fasting subjects at baseline and on the morning after the last GH injection for measurement of IGF-I and IGFBP-3. Plasma GH levels fell within normal limits in the HIV-seropositive patients and were similar to those of healthy children (1.31 +/- 1.18 vs. 1.57 +/- 1.16 microg/liter, respectively; mean +/- SD). The population mean cosinor analysis shows that the GH circadian rhythm reached statistical significance both in the HIV-seropositive children and in the control group. Despite this, the IGF-I and IGFBP-3 levels were significantly lower in HIV-infected children than in the control group (75.6 +/- 57.2 vs. 233.3 +/- 52.5 ng/ml, p < 0.001 and 2.09 +/- 0.17 vs. 3.89 +/- 0.24 mg/liter, p < 0.01, respectively; mean +/- SD); moreover, the response of IGF-I and IGFBP-3 to the IGF-I generation test was significantly lower in HIV-infected children than in the control group (86.3 +/- 55.8 vs. 257.5 +/- 53.4 ng/ml, p < 0.001 and 3.14 +/- 0.43 mg/liter, p < 0.01, respectively; mean +/- SD). It appears that circadian GH secretion is normal in children with HIV infection, but the response to exogenous GH with regard to IGF-I and IGFBP-3

  5. Seasonal response of ghrelin, growth hormone, and insulin-like growth factor I in the free-ranging Florida manatee (Trichechus manatus latirostris)

    Science.gov (United States)

    Tighe, Rachel L; Bonde, Robert K.; Avery, Julie P.

    2016-01-01

    Seasonal changes in light, temperature, and food availability stimulate a physiological response in an animal. Seasonal adaptations are well studied in Arctic, Sub-Arctic, and hibernating mammals; however, limited studies have been conducted in sub-tropical species. The Florida manatee (Trichechus manatus latirostris), a sub-tropical marine mammal, forages less during colder temperatures and may rely on adipose stores for maintenance energy requirements. Metabolic hormones, growth hormone (GH), insulin-like growth factor (IGF)-I, and ghrelin influence growth rate, accretion of lean and adipose tissue. They have been shown to regulate seasonal changes in body composition. The objective of this research was to investigate manatee metabolic hormones in two seasons to determine if manatees exhibit seasonality and if these hormones are associated with seasonal changes in body composition. In addition, age related differences in these metabolic hormones were assessed in multiple age classes. Concentrations of GH, IGF-I, and ghrelin were quantified in adult manatee serum using heterologous radioimmunoassays. Samples were compared between short (winter) and long (summer) photoperiods (n = 22 male, 20 female) and by age class (adult, juvenile, and calf) in long photoperiods (n = 37). Short photoperiods tended to have reduced GH (p = 0.08), greater IGF-I (p = 0.01), and greater blubber depth (p = 0.03) compared with long photoperiods. No differences were observed in ghrelin (p = 0.66). Surprisingly, no age related differences were observed in IGF-I or ghrelin concentrations (p > 0.05). However, serum concentrations of GH tended (p = 0.07) to be greater in calves and juveniles compared with adults. Increased IGF-I, greater blubber thickness, and reduced GH during short photoperiod suggest a prioritization for adipose deposition. Whereas, increased GH, reduced blubber thickness, and decreased IGF-I in long photoperiod suggest prioritization of lean tissue

  6. Effect of acute sleep deprivation and recovery on Insulin-like Growth Factor-I responses and inflammatory gene expression in healthy men.

    Science.gov (United States)

    Chennaoui, Mounir; Drogou, Catherine; Sauvet, Fabien; Gomez-Merino, Danielle; Scofield, Denis E; Nindl, Bradley C

    2014-01-01

    Acute sleep deprivation in humans has been found to increase inflammatory markers and signaling pathways in the periphery through a possible Toll-like receptor 4 (TLR-4). In addition, short duration sleep has been associated with low circulating total Insulin-like Growth Factor-I (IGF-I) concentrations. We aimed to determine whether a total sleep deprivation (TSD) protocol with recovery altered whole-blood gene expression of the proinflammatory cytokines TNF-α and IL-6, as well as TLR-4 expression, and to examine the relationship with circulating concentrations of the IGF-I system. Twelve healthy men participated in a five-day TSD (two control nights followed by one night of sleep deprivation and one night of recovery). Blood was sampled at 0800, before and after sleep deprivation (D2 and D4), and after recovery (D5). It is shown that 25 h of sleep deprivation (D4) induced significant increases in mRNA levels of TNF-α and its soluble receptor R1 (Precovery was sufficient to restore basal expression levels for TNF-α, sTNF-R1, TLR-4 and circulating IGF-I. Changes in TLR-4 mRNA levels during the protocol correlated positively with those of TNF-α and sTNF-R1 (r=0.393 and r=0.490 respectively), and negatively with circulating free IGF-I (r=-0.494). In conclusion, 25 h of sleep deprivation in healthy subjects is sufficient to induce transient and reversible genomic expression of the pro-inflammatory cytokine TNF-α and its R1 receptor, and its mediator TLR-4, with a possible link to IGF-I axis inhibition.

  7. Differential responsiveness of luteinized human granulosa cells to gonadotropins and insulin-like growth factor I for induction of aromatase activity

    International Nuclear Information System (INIS)

    Christman, G.M.; Randolph, J.F. Jr.; Peegel, H.; Menon, K.M.

    1991-01-01

    The objective of this study was to examine the in vitro responsiveness of cultured luteinized human granulosa cells over time to insulin-like growth factor 1 (IGF-1), human follicle-stimulating hormone (FSH), and human chorionic gonadotropin (hCG) for the induction of aromatase activity. Granulosa cells were retrieved from preovulatory follicles in patients undergoing in vitro fertilization. Cells were cultured for a period of 72 hours or 10 days. The ability of hCG, human FSH, and/or IGF-I to induce aromatase activity was assayed by the stereospecific release of tritium from [1B-3H]androstenedione. Short-term cultures (72 hours) demonstrated a marked rise in aromatase activity in response to human FSH and IGF-I, whereas a smaller response to hCG was observed. In contrast, 10-day cultures demonstrated responsiveness predominantly to hCG rather than human FSH for the induction of aromatase activity with no remarkable effect of IGF-I. Luteinized human granulosa cells undergo a transformation from an initial human FSH and IGF-I responsive state to an hCG responsive state in long-term cultures

  8. Insulin-like growth factor I: a biologic maturation indicator.

    Science.gov (United States)

    Ishaq, Ramy Abdul Rahman; Soliman, Sanaa Abou Zeid; Foda, Manal Yehya; Fayed, Mona Mohamed Salah

    2012-11-01

    Determination of the maturation level and the subsequent evaluation of growth potential during preadolescence and adolescence are important for optimal orthodontic treatment planning and timing. This study was undertaken to evaluate the applicability of insulin-like growth factor I (IGF-I) blood level as a maturation indicator by correlating it to the cervical vertebral maturation index. The study was conducted with 120 subjects, equally divided into 60 males (ages, 10-18 years) and 60 females (ages, 8-16 years). A lateral cephalometric radiograph and a blood sample were taken from each subject. For each subject, cervical vertebral maturation and IGF-I serum level were assessed. Mean values of IGF-I in each stage of cervical vertebral maturation were calculated, and the means in each stage were statistically compared with those of the other stages. The IGF-I mean value at each cervical vertebral maturation stage was statistically different from the mean values at the other stages. The highest mean values were observed in stage 4, followed by stage 5 in males and stage 3 in females. IGF-I serum level is a reliable maturation indicator that could be applied in orthodontic diagnosis. Copyright © 2012 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

  9. Enteral nutrients potentiate the intestinotrophic action of glucagon-like peptide-2 in association with increased insulin-like growth factor-I responses in rats

    DEFF Research Database (Denmark)

    Liu, Xiaowen; Murali, Sangita G; Holst, Jens Juul

    2008-01-01

    of GLP-2 and IGF-I system components are increased with the mucosal growth induced by enteral nutrient (EN) and/or a low dose of GLP-2 in parentally-fed rats. Rats were randomized to 4 treatment groups using a 2x2 design and maintained with parental nutrition (PN) for 7 days: PN alone, EN, GLP-2, EN......: parenteral nutrition, GLP-2 receptor, IGF binding protein-3 and -5, proglucagon....

  10. 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...

  11. The pivotal role of insulin-like growth factor I in normal mammary development.

    Science.gov (United States)

    Kleinberg, David L; Barcellos-Hoff, Mary Helen

    2011-09-01

    Mammary development begins in puberty in response to an estrogen (E(2)) surge. E(2) does not act alone. It relies on pituitary growth hormone (GH) to induce insulin-like growth factor I (IGF-I) production in the mammary stromal compartment. In turn, IGF-I permits E(2) (and progesterone) action. During puberty, E(2) and IGF-I synergize for ductal morphogenesis. During pregnancy, progesterone joins IGF-I and E(2) to stimulate secretory differentiation necessary to produce milk. Prolactin stimulates milk production, while transforming growth factor-β inhibits proliferation. The orchestrated action of hormones, growth factors, and receptors necessary for mammary development and function are also critical in breast cancer. Copyright © 2011. Published by Elsevier Inc.

  12. Growth hormone-insuline-like growth factor-I system in pejerrey Odontesthes bonariensis (Atheriniformes

    Directory of Open Access Journals (Sweden)

    S.E. Arranz

    2008-07-01

    Full Text Available Using biotechnology to increase the growth rates of fish is likely to reduce production costs per unit of food. Among vertebrates, fish appear to occupy a unique position, when growth patterns are considered. With few exceptions, fish species tend to grow indeterminately, implying that size is never fixed. Both hyperplasia and hypertrophy contribute to post-larval muscle growth in fish. Growth hormone (GH - Insulin-like Growth Factor I (IGF-I is the most important growth axis in fish. Our experimental model, the pejerrey, Odontesthes bonariensis (Ateriniformes is a South American inland water fish considered to be a promising species for intensive aquaculture. However, one major drawback to achieve this goal is its slow growth in captivity. In order to understand how growth is regulated in this species, our first objective was to characterized pejerrey GH- IGF-I axis. We first cloned and characterized pejerrey (pj GH, IGF-I and the growth hormone receptors (GHRs I and II. In addition to providing valuable data for evolutionary comparison of GH, investigation of GH action in teleosts is particularly important because of its potential application in aquaculture. GH can not only promote the somatic growth in fish but also lower dietary protein requirements. A prerequisite for providing sufficient amounts of GH for basic research and aquaculture application is a large-scale production of GH. For that purpose, recombinant pjGH was expressed in a bacterial system. Protocols for solubilization and proper folding were achieved. Activity of recombinant pjGH was assessed in fish by measuring the liver IGF-I response to different doses of GH. IGF-I transcript was measured in the liver after pjGHr in vivo stimulation by means of quantitative real-time PCR assays. A dose-dependent response of IGF-I mRNA was observed after pjGHr administration, and reached a 6 fold IGF-I maximum increase over control group when 2.5 µg pjGH /g-body weight were injected

  13. Insulin-like growth factor-I and the liver

    DEFF Research Database (Denmark)

    Bonefeld, Karen; Møller, Søren

    2011-01-01

    consequences in cirrhosis are only partly understood. Disruption of the growth hormone (GH)-IGF-I axis seems to be closely associated with the development of liver disease, and treatment with recombinant human IGF (rhIGF)-I has been shown to halt, and even reverse, the fibrotic degeneration. IGF-I in itself......Insulin-like growth factors (IGFs) play an essential role in growth and development, as well as in the overall cellular regulation and metabolism in the human body. In chronic liver disease, IGF levels are decreased, and the circulating levels correlate to the extent of hepatocellular dysfunction...

  14. Expression, content, and localization of insulin-like growth factor I in human achilles tendon

    DEFF Research Database (Denmark)

    Olesen, Jens L; Heinemeier, Katja M; Langberg, Henning

    2006-01-01

    In animals insulin-like growth factor I (IGF-I) stimulates collagen production by fibroblasts and is expressed in tendons together with its binding protein 4 (IGFBP-4). However, the presence of IGF-I and IGFBP-4 in human tendon tissue is not described. Tissue IGF-I content was examined by immunof...... the tendon fibroblasts and that mRNA for IGF-I and IGFBP-4 can be determined in human tendon tissue. The present study adds support for the roles of IGF-I and IGFBP-4 in the regulation of tendon adaptive responses to mechanical loading....

  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 more...... patients with primary or secondary IGFD is likely with investigative and diagnostic progress, particularly in the assessment of children with idiopathic short stature. Diagnosis of IGFD requires accurate and reliable IGF-I assays, adequate normative data for reference, and knowledge of IGF-I physiology...

  16. Specific immunoradiometric assay of insulin-like growth factor I with use of monoclonal antibodies

    Energy Technology Data Exchange (ETDEWEB)

    Scott, M.G.; Cuca, G.C.; Petersen, J.R.; Lyle, L.R.; Burleigh, B.D.; Daughaday, W.H.

    1987-11-01

    We identified two monoclonal antibodies that bind spatially distinct epitopes on insulin-like growth factor I (IGF-I). Using these two antibodies, we developed a simultaneous, two-site immunoradiometric assay (IRMA) specific for IGF-I. This IRMA has no detectable cross reactivity with insulin, proinsulin, prolactin, or somatotropin, and less than 2% crossreactivity with IGF-II. The assay response varies linearly with IGF-I concentrations of 0-800 micrograms/L in serum; the detection limit is about 10 micrograms/L. A comparison of 26 IGF-I serum values from the IRMA and from a previously reported IGF-I specific RIA gave a correlation coefficient of 0.96 with no substantial bias (slope = 1.10). IGF-I values for serum, as an aid in assessing growth abnormalities, are easily (only three pipetting steps) obtained in less than 4 h.

  17. Polysomnographic sleep, growth hormone insulin-like growth factor-I axis, leptin, and weight loss

    DEFF Research Database (Denmark)

    Rasmussen, Michael; Wildschiødtz, Gordon; Juul, Anders

    2008-01-01

    severely obese subjects (BMI: 41+/-1 kg/m(2), 32+/-2 years of age), cross-sectional at baseline, and longitudinal after a dramatically diet-induced weight loss (36+/-7 kg). Ten age- and gender-matched nonobese subjects served as controls. Sleep duration (360+/-17 vs. 448+/-15 min/night; P... compared with nonobese subjects After diet-induced weight loss the differences in GH, free IGF-I, and leptin were no longer present between previously obese and nonobese subjects, whereas a significant difference in sleep duration and total IGF-I levels persisted. Rapid eye movement (REM) sleep, non......Short sleep appears to be strongly associated with obesity and altered metabolic function, and sleep and growth hormone (GH) secretion seems interlinked. In obesity, both the GH-insulin-like-growth-factor-I (GH-IGF-I) axis and sleep have been reported to be abnormal, however, no studies have...

  18. Serum insulin-like growth factor-I and body composition in community dwelling older people

    NARCIS (Netherlands)

    Jakobsdottir, S.; van Nieuwpoort, I.C.; Schaap, L.A.; van Schoor, N.M.; Lips, P.T.A.M.; Drent, M.L.

    2010-01-01

    Objectives The decline in the growth hormoneinsulin-like growth factor-I (GHIGF-I) axis during normal aging might be involved in the changes in body composition associated with increasing age. We conducted a study to investigate serum IGF-I levels across different age categories and a possible

  19. Detection of polymorphism of the insulin-like growth factor-I (IGF-I ...

    African Journals Online (AJOL)

    Molecular genetic selection on individual genes is a promising method to genetically improve economically important traits in chickens. The insulin-like growth factor-I (IGF-I) gene may play important roles in growth of multiple tissues, including muscle cells, cartilage and bone. In the present study, polymorphism of the ...

  20. Human conditions of insulin-like growth factor-I (IGF-I deficiency

    Directory of Open Access Journals (Sweden)

    Puche Juan E

    2012-11-01

    Full Text Available Abstract Insulin-like growth factor I (IGF-I is a polypeptide hormone produced mainly by the liver in response to the endocrine GH stimulus, but it is also secreted by multiple tissues for autocrine/paracrine purposes. IGF-I is partly responsible for systemic GH activities although it possesses a wide number of own properties (anabolic, antioxidant, anti-inflammatory and cytoprotective actions. IGF-I is a closely regulated hormone. Consequently, its logical therapeutical applications seems to be limited to restore physiological circulating levels in order to recover the clinical consequences of IGF-I deficiency, conditions where, despite continuous discrepancies, IGF-I treatment has never been related to oncogenesis. Currently the best characterized conditions of IGF-I deficiency are Laron Syndrome, in children; liver cirrhosis, in adults; aging including age-related-cardiovascular and neurological diseases; and more recently, intrauterine growth restriction. The aim of this review is to summarize the increasing list of roles of IGF-I, both in physiological and pathological conditions, underlying that its potential therapeutical options seem to be limited to those proven states of local or systemic IGF-I deficiency as a replacement treatment, rather than increasing its level upper the normal range.

  1. Effects of insulin-like growth factor I or human growth hormone in fasted rats.

    Science.gov (United States)

    Asakawa, K; Hizuka, N; Takano, K; Horikawa, R; Sukegawa, I; Demura, H; Shizume, K

    1992-03-01

    To study the effect of insulin-like growth factor I (IGF-I) treatment on growth and metabolism in fasted rats and compare it with the effect of human growth hormone (hGH), we infused 120 micrograms/ml IGF-I continuously or injected 200 micrograms hGH twice a day in fasted rats. After a 3 1/2-day administration of IGF-I in fasted rats, the body weights, kidney, spleen and adrenal gland weights were greater than those for untreated fasted rats (control). The body weights and the organ weights in hGH treated rats did not differ from those in control rats. Serum IGF-I levels in control, hGH treated and IGF-I treated rats were 64.0 +/- 6.1, 107.5 +/- 6.9 and 129.8 +/- 6.3 ng/ml, respectively, which were significantly different from each other. Blood urea nitrogen (BUN) levels were 13.9 +/- 1.1 ng/ml in IGF-I treated rats, which were significantly lower than those of control rats. Human GH treatment did not change BUN but affected nonesterified fatty acid (NEFA) and triglyceride. In IGF-I treated rats three-day urinary excretion of nitrogen and creatine were 163.5 +/- 14.6 mg and 9.53 +/- 1.53 mg, which were significantly less than those in control rats. These data indicate that IGF-I infusion inhibits body weight loss and catabolism in fasted rats and might be a useful therapy in catabolic conditions.

  2. Renal protein synthesis in diabetes mellitus: effects of insulin and insulin-like growth factor I

    International Nuclear Information System (INIS)

    Barac-Nieto, M.; Lui, S.M.; Spitzer, A.

    1991-01-01

    Is increased synthesis of proteins responsible for the hypertrophy of kidney cells in diabetes mellitus? Does the lack of insulin, and/or the effect of insulin-like growth factor I (IGFI) on renal tubule protein synthesis play a role in diabetic renal hypertrophy? To answer these questions, we determined the rates of 3H-valine incorporation into tubule proteins and the valine-tRNA specific activity, in the presence or absence of insulin and/or IGFI, in proximal tubule suspension isolated from kidneys of streptozotocin diabetic and control rats. The rate of protein synthesis increased, while the stimulatory effects of insulin and IGFI on tubule protein synthesis were reduced, early (96 hours) after induction of experimental diabetes. Thus, hypertrophy of the kidneys in experimental diabetes mellitus is associated with increases in protein synthesis, rather than with decreases in protein degradation. Factor(s) other than the lack of insulin, or the effects of IGFI, must be responsible for the high rate of protein synthesis present in the hypertrophying tubules of diabetic rats

  3. Growth hormone increases and insulin-like growth factor-I decreases circulating lipoprotein(a)

    Science.gov (United States)

    Laron, Z; Wang, X L; Klinger, B; Silbergeld, A; Wilcken, D E

    1997-04-01

    Elevated serum lipoprotein(a) (Lp(a)) is a strong risk factor for coronary artery disease (CAD). Genetic factors appear to account for the major variance in Lp(a) levels but the contribution hormones make in modulating Lp(a) levels is not yet clear. In the present investigation we determined the effects of human growth hormone (hGH) and insulin-like growth factor-I (IGF-I) on circulating Lp(a). Four groups of patients were studied. Group a: adults with GH deficiency (n = 7) treated with hGH (0.05 U/kg/day, s.c.); group b: girls with Turner syndrome (n = 7) treated with hGH (0.1 U/kg/day, s.c.); group c: prepubertal boys with idiopathic short stature (n = 6) treated with the GH secretagogue (GHRP) hexarelin (60 micrograms t.i.d. intranasally); group d: Laron syndrome patients (n = 10) treated with IGF-I (100-200 micrograms/kg/day, s.c.). Following overnight fasting, serum was sampled before the initiation of treatment and during 6-9 months treatment. Serum IGF-I rose significantly in all the subjects in all four groups. In the first three groups in which IGF-I was elevated by exogenous or endogenous GH stimulation, serum Lp(a) increased significantly (119 +/- 35%, P hGH or GHRP (65.2 +/- 31%, P = 0.109; 93.7 +/- 53%, P = 0.062; 353.8 +/- 52.7%, P hGH in children and adults and the role of Lp(a) as a CAD risk factor.

  4. [Insulin-like growth factor I (IGF-I) and liver cirrhosis].

    Science.gov (United States)

    Conchillo, M; Prieto, J; Quiroga, J

    2007-03-01

    Insulin-like growth factor I (IGF-I) is a polypeptide hormone secreted by multiple tissues in response to growth hormone (GH). It is partly responsible for GH activity, and also has glucose-lowering and anabolizing effects. Ninety percent of circulating IGF-I originates in the liver and has autocrine, paracrine, and endocrine effects, the latter on multiple tissues. Liver cirrhosis results in a progressive decline of hepatic IGF-I output, and this factor may become undetectable in advanced disease. Some cirrhosis complications, mainly those nutritional and metabolic in nature (insuline resistance, malnutrition, osteopenia, hypogonadism, intestinal disorders), may be at least partly related to this IGF-I deficiency, since some IGF-I effects represent a reverse image of cirrhosis complications. Despite this, IGF-I replacement therapy has been never suggested for cirrhosis. A number of experimental studies in cirrhotic rats showed that therapy using low-dose recombinant IGF-I exerts two types of effect on experimental cirrhosis: a) liver improvement driven by improved hepatocellular function, portal hypertension, and liver fibrosis; and b) cirrhosis-related extrahepatic disorder improvement driven by improved food efficiency, muscle mass, bone mass, gonadal function and structure, and intestinal function and structure, with a normalization of sugar and amino acid malabsorption, and improved intstinal barrier function, manifested by reduced endotoxemia and bacterial translocation. Subsequently, the first randomized, double-blind, placebo-controlled, pilot clinical trial in a small number of cirrhotic patients showed increased serum albumin and improved energy metabolism as a result of IGF-I use. Further clinical trials are needed to identify adequate IGF-I doses, administration duration and frequency, and the subgroup of cirrhotic patients who will benefit most from this replacement therapy.

  5. The pubertal spurt: effects of sex steroids on growth hormone and insulin-like growth factor I.

    Science.gov (United States)

    Caufriez, A

    1997-02-01

    In puberty, the growth spurt and the appearance of secondary sex characteristics occur concomitantly with an increase of sex steroids, growth hormone (GH) and insulin-like growth factor I (IGF-I). A number of experiments indicate that sex steroids exert a stimulatory action on the somatotropic axis. This effect is due to an amplifying action of oestradiol (secreted by the ovaries or after testosterone aromatization) on the neuroendocrine regulation of pulsatile GH release.

  6. Growth and Growth hormone - Insulin Like Growth Factor -I (GH-IGF-I) Axis in Chronic Anemias.

    Science.gov (United States)

    Soliman, Ashraf T; De Sanctis, Vincenzo; Yassin, Mohamed; Adel, Ashraf

    2017-04-28

    Anaemia is a global public health problem affecting both developing and developed countries with major consequences for human health as well as social and economic development. It occurs at all stages of the life cycle, but is more prevalent in pregnant women and young children. Iron deficiency anaemia (IDA) was considered to be among the most important contributing factors to the global burden of disease. Prolonged and/or chronic anemia has a negative effect on linear growth especially during the rapid phases (infancy and puberty). Additionally infants with chronic IDA have delayed cognitive, motor, and affective development that may be long-lasting. In view of the significant impact of chronic anemias on growth, pediatricians endocrinologists and hematologists should advocate primary prevention and screening for growth disturbance in these forms of anemias. The extent of the negative effect of different forms of chronic anemias on linear growth and its possible reversibilty is addressed in this review. The possible mechanisms that may impair growth in the different forms of anemias are addressed with special attention to their effect on the growth hormone (GH) - insulin like growth factor -I (IGF-I).

  7. Increased hepatic expression of insulin-like growth factor-I receptor in chronic hepatitis C

    Science.gov (United States)

    Stefano, José Tadeu; Corrêa-Giannella, Maria Lúcia; Ribeiro, Cristiane Maria Freitas; Alves, Venâncio Avancini Ferreira; Massarollo, Paulo Celso Bosco; Machado, Marcel Cerqueira Cesar; Giannella-Neto, Daniel

    2006-01-01

    AIM: Although increased insulin-like growth factor-I receptor (IGF-IR) gene expression has been reported in hepatocellular carcinoma, studies assessing IGF-IR in chronic hepatitis C (CHC) and cirrhosis are scarce. We therefore aimed to evaluate IGF-IR and IGF-I mRNA expression in liver from patient with CHC. METHODS: IGF-IR and IGF-I mRNA content were determined by semi-quantitative RT-PCR and IGF-IR protein expression was determined by immunohisto-chemistry in hepatic tissue obtained from patients with CHC before (34 patients) and after (10 patients) therapy with interferon-α and ribavirin. RESULTS: An increase of IGF-IR mRNA content was observed in hepatic tissue obtained from all CHC patients as well as from 6 cadaveric liver donors following orthopic transplantation (an attempt to evaluate normal livers) in comparison to normal liver, while no relevant modifications were detected in IGF-I mRNA content. The immunohistochemical results showed that the raise in IGF-IR mRNA content was related both to ductular reaction and to increased IGF-IR expression in hepatocytes. A decrease in IGF-IR mRNA content was observed in patients who achieved sustained virological response after therapy, suggesting an improvement in hepatic damage. CONCLUSION: The up-regulation of IGF-IR expression in hepatocytes of patients with CHC could constitute an attempt to stimulate hepatocyte regeneration. Considering that liver is the organ with the highest levels of IGF-I, our finding of increased IGF-IR expression after both acute and chronic hepatic damage highlights the need for additional studies to elucidate the role of IGF-I in liver regeneration. PMID:16804965

  8. Insulin-like growth factors I and II in healthy women with and without established osteoporosis

    DEFF Research Database (Denmark)

    Ravn, Pernille; Spencer, E M; Christiansen, C

    1995-01-01

    .05) was seen in the nandrolone decanoate-treated group. The same tendency was seen for hormone replacement therapy, although it was not significant. In conclusion, the serum level of IGF-I is high in young women, when peak bone mass is attained, and low in postmenopausal women with established osteoporosis.......We measured serum concentrations of insulin-like growth factors I and II (IGF-I and IGF-II) by radioimmunoassay in 107 healthy women aged 28-78 years and in 116 women with established osteoporosis. The women with established osteoporosis were randomized to a 1-year double-blind, placebo...

  9. Diminished concentrations of insulin-like growth factor I in cystic fibrosis

    DEFF Research Database (Denmark)

    Laursen, Erik; Juul, A; Lanng, S

    1995-01-01

    Cystic fibrosis is frequently accompanied by a catabolic condition with low body mass index caused by a number of disease complications. Insulin-like growth factor-I (IGF-I) is an anabolic hormone and an important marker of nutritional status, liver function, and linear growth. Available data...... on IGF-I in cystic fibrosis are sparse and conflicting. From 1990-3, 235 of our 240 patients (114 males, 121 females, median age 16.2 years, ranged 0.1-44.0 years) had IGF-I measured once by radioimmunoassay. IGF-I was significantly reduced compared with a healthy Scandinavian control population: mean...... = 0.28, p cystic fibrosis and play a part in their abnormal growth pattern....

  10. Exercise-induced insulin-like growth factor I system concentrations after training in women.

    Science.gov (United States)

    Gregory, Sara M; Spiering, Barry A; Alemany, Joseph A; Tuckow, Alexander P; Rarick, Kevin R; Staab, Jeffery S; Hatfield, Disa L; Kraemer, William J; Maresh, Carl M; Nindl, Bradley C

    2013-03-01

    This study examined the effects of short-term physical training on the acute hormonal response (i.e., growth hormone, total and free insulin-like growth factor I [IGF-I], and IGF binding proteins [IGFBP]-1, IGFBP-2, and IGFBP-3) to resistance exercise (RE) in women. Forty-six women (20.3 ± 0.3 yr, mass = 64.1 ± 7.3 kg, height = 165.7 ± 1.0 cm) were randomly assigned to an endurance training (E), resistance training (R), combined training (R + E), or control (C) group for 8wk. Subjects completed a standardized bout of RE (six sets of back squats at 10 repetition maximum) before and after training. Blood samples were obtained at rest (PRE), after the third set, immediately postexercise (POST), and at 15 min and 30 min after exercise. Acute RE significantly increased (P change from PRE to POST = +10.9 ± 7.5 μg·L-1), total IGF-I (+66.1 ± 25.4 μg·L-1), IGFBP-1 (+2.5 ± 3.1 μg·L-1), IGFBP-2 (+86.0 ± 86.8 μg·L-1), and IGFBP-3 (+0.69 ± 0.25 mg·L-1) concentrations and decreased free IGF-I concentrations (-0.14 ± 0.21 μg·L-1). After 8 wk of training, total IGF-I concentrations were significantly increased (change in POST concentrations from week 0 to week 8 = +82.5 ± 120.8 μg·L-1), and IGFBP-1 concentrations were significantly decreased (-6.7 ± 13.6 μg·L-1) during exercise in groups that participated in resistance training (R and R + E); no significant changes were seen after E or C. Participation in resistance training increased total IGF-I and reduced IGFBP-1 concentrations during acute RE, indicating exercise mode-specific adaptations in the circulating IGF-I system.

  11. Enhanced insulin-like growth factor I gene expression in regenerating rat pancreas

    International Nuclear Information System (INIS)

    Smith, F.E.; Rosen, K.M.; Villa-Komaroff, L.; Weir, G.C.; Bonner-Weir, S.

    1991-01-01

    Insulin-like growth factor I (IGF-I) mRNA expression was studied after 90% partial pancreatectomy in the rat to determine whether IGF-I was associated with pancreatic regeneration. The level of IGF-I mRNA was maximally increased (4-fold above control value) 3 days after pancreatectomy, but thereafter gradually decreased, returning to control levels by 14 days after surgery. By in situ hybridization, IGF-I mRNA in both pancreatectomized and sham-operated rats was localized to capillary endothelial cells, indicating that this is the site of IGF-I expression in the normal rat pancreas. However, enhanced IGF-I mRNA expression was localized to focal areas of regeneration unique to pancreatectomized rats. In these areas, epithelial cells of proliferating ductules and individual connective tissue cells expressed IGF-I, suggesting that IGF-I may play an important role in the growth or differentiation of pancreatic tissue

  12. Enhanced insulin-like growth factor I gene expression in regenerating rat pancreas

    Energy Technology Data Exchange (ETDEWEB)

    Smith, F.E.; Rosen, K.M.; Villa-Komaroff, L.; Weir, G.C.; Bonner-Weir, S. (E. P. Joslin Research Laboratory, Joslin Diabetes Center, Harvard Medical School, Boston, MA (USA))

    1991-07-15

    Insulin-like growth factor I (IGF-I) mRNA expression was studied after 90% partial pancreatectomy in the rat to determine whether IGF-I was associated with pancreatic regeneration. The level of IGF-I mRNA was maximally increased (4-fold above control value) 3 days after pancreatectomy, but thereafter gradually decreased, returning to control levels by 14 days after surgery. By in situ hybridization, IGF-I mRNA in both pancreatectomized and sham-operated rats was localized to capillary endothelial cells, indicating that this is the site of IGF-I expression in the normal rat pancreas. However, enhanced IGF-I mRNA expression was localized to focal areas of regeneration unique to pancreatectomized rats. In these areas, epithelial cells of proliferating ductules and individual connective tissue cells expressed IGF-I, suggesting that IGF-I may play an important role in the growth or differentiation of pancreatic tissue.

  13. Effect of fat supplementation on leptin, insulin-like growth factor I, growth hormone, and insulin in cattle.

    Science.gov (United States)

    Becú-Villalobos, Damasia; García-Tornadú, Isabel; Shroeder, Guillermo; Salado, Eloy E; Gagliostro, Gerardo; Delavaud, Carole; Chilliard, Yves; Lacau-Mengido, Isabel M

    2007-07-01

    We investigated the effect of fat supplementation on plasma levels of hormones related to metabolism, with special attention to leptin, in cows in early lactation and in feedlot steers. In experiment 1, 34 lactating cows received no fat or else 0.5 or 1.0 kg of partially hydrogenated oil per day in addition to their basal diet from day 20 before the expected calving date to day 70 postpartum. In experiment 2, part of the corn in the basal concentrate was replaced with 0.7 kg of the same oil such that the diets were isocaloric; 18 cows received the fat-substituted diet and 18 a control diet from day 20 before the expected calving date to day 75 postpartum. In experiment 3, calcium salts of fatty acids were added to the basal diet of 14 feedlot steers for 80 d; another 14 steers received a control diet. The basal plasma levels of leptin were higher in the cows than in the steers. Dietary fat supplementation did not affect the leptin levels in the lactating cows but lowered the levels in the feedlot steers despite greater energy intake and body fatness (body weight) in the steers receiving the supplement than in those receiving the control diet. The levels of insulin-like growth factor I and insulin were decreased with dietary fat supplementation in the lactating cows but were unaffected in the steers, suggesting that responses to fat ingestion depend on the physiological state of the animal, including age and sex. Finally, no effects of supplementary fat on the level of growth hormone were demonstrated in any of the models.

  14. Insulin-like growth factors I and II in healthy women with and without established osteoporosis

    DEFF Research Database (Denmark)

    Ravn, Pernille; Spencer, E M; Christiansen, C

    1995-01-01

    We measured serum concentrations of insulin-like growth factors I and II (IGF-I and IGF-II) by radioimmunoassay in 107 healthy women aged 28-78 years and in 116 women with established osteoporosis. The women with established osteoporosis were randomized to a 1-year double-blind, placebo...... no correlation between IGF-I and age (r = 0.02). Correspondingly, we found no significant changes in serum IGF-I in 10 women, who were followed with serial measurements of IGFs every 3 months from 2 years before to 1 year after menopause; IGF-II revealed no correlation with age (r = 0.04). In the group of 116...... women with established osteoporosis, IGF-I was 30% lower (p

  15. Application of insulin-like growth factor-I and insulin release test in diabetes mellitus

    International Nuclear Information System (INIS)

    Chen Dong; Ma Yongxiu; Duan Wenruo

    2003-01-01

    The purpose of this study was to determine the role of insulin-like growth factor-I (IGF-I) and insulin release test (IRT) in understanding the extent of damage to ability of reducing blood sugar in different types of diabetes mellitus (DM) and in selection of treatment plan and adjustment of using drugs. OGTT, IRT and determination of IGF-I level of 67 normal subjects and 217 DM patients were performed. The result was analyzed comparatively. The level of IGF-I was negatively correlated with the level of fasting blood sugar, and positively correlated with the level of fasting insulin. Our conclusions are: There are two ways of reducing blood sugar: one is by insulin, and the other is by IGF-I. IRT can reflect the former better, and IGF-I the latter. The combination of these two is of significant value in diagnosis and treatment of DM

  16. Effects of immune challenge on concentrations of serum insulin-like growth factor-I and growth performance in pigs.

    OpenAIRE

    Hevener, W; Routh, P A; Almond, G W

    1999-01-01

    This study was designed to determine the long-term effects of repeated endotoxin treatment or immunization against human serum albumin on concentrations of serum insulin-like growth factor-I (IGF-I) and other indicators of growth performance in growing pigs. Thirty gilts (38.5 +/- 0.9 kg) were randomly assigned to 5 treatment groups (n = 6 animals/group): 1) lipopolysaccharide injections, 2) lipopolysaccharide pair-fed, 3) human serum albumin immunization, 4) human serum albumin pair-fed, and...

  17. Diminished concentrations of insulin-like growth factor I in cystic fibrosis

    DEFF Research Database (Denmark)

    Laursen, Erik; Juul, A; Lanng, S

    1995-01-01

    on IGF-I in cystic fibrosis are sparse and conflicting. From 1990-3, 235 of our 240 patients (114 males, 121 females, median age 16.2 years, ranged 0.1-44.0 years) had IGF-I measured once by radioimmunoassay. IGF-I was significantly reduced compared with a healthy Scandinavian control population: mean......Cystic fibrosis is frequently accompanied by a catabolic condition with low body mass index caused by a number of disease complications. Insulin-like growth factor-I (IGF-I) is an anabolic hormone and an important marker of nutritional status, liver function, and linear growth. Available data...... (-2 SD to +2 SD) IGF-I SD score was -0.97 (-3.7 to 1.7) in males and -0.67 (-3.2 to 1.9) in females. Height SD score was -0.95 (-3.3 to 1.4) in males and -0.81 (-3.2 to 1.6) in females. In patients who were still in the growth period a significant correlation of IGF-I SD score to height SD score (r...

  18. The role of insulin-like growth factor-I in the physiopathology of hearing

    Directory of Open Access Journals (Sweden)

    Silvia eMurillo-Cuesta

    2011-07-01

    Full Text Available Insulin like growth factor I (IGF-I belongs to the family of polypeptides of insulin, which play a central role in embryonic development and adult nervous system homeostasis by endocrine, autocrine and paracrine mechanisms. IGF-I is fundamental for the regulation of cochlear development, growth and differentiation, and its mutations are associated with hearing loss in mice and men. Low levels of IGF-I have been shown to correlate with different human syndromes showing hearing loss and with presbyacusis. Animal models are fundamental to understand the genetic, epigenetic, and environmental factors that contribute to human hearing loss. In the mouse, IGF-I serum levels decrease with ageing and there is a concomitant hearing loss and retinal degeneration. In the Igf1-/- null mouse, hearing loss is due to neuronal loss, poor innervation of the sensory hair cells and age-related stria vascularis alterations. In the inner ear, IGF-I actions are mediated by intracellular signaling networks, RAF, AKT and p38 MAPK protein kinases modulate the expression and activity of transcription factors, as AP1, MEF2, FoxM1 and FoxP3, leading to the regulation of cell cycle and metabolism. Therapy with rhIGF-I has been approved in humans for the treatment of poor linear growth and certain neurodegenerative diseases. This review will discuss these findings and their implications in new IGF-I-based treatments for the protection or repair of hearing loss.

  19. Plasma leptin and insulin-like growth factor I levels during acute exacerbations of chronic obstructive pulmonary disease

    OpenAIRE

    Kythreotis, Prokopis; Kokkini, Ageliki; Avgeropoulou, Stavrina; Hadjioannou, Argyro; Anastasakou, Efgenia; Rasidakis, Antonis; Bakakos, Petros

    2009-01-01

    Abstract Background Recent studies have provided evidence for a link between leptin and tumor necrosis factor-alpha (TNF-α). Insulin-like growth factor I (IGF-I) mediates the metabolic effects of growth hormone (GH). The GH axis is believed to be suppressed in chronic obstructive pulmonary disease (COPD). The aim of this study is to find out whether acute exacerbations of COPD are followed by changes in plasma leptin and insulin-like growth factor I (IGF-I) levels and furthermore, whether the...

  20. The correlations between insulin-like growth factor I, insulin and gestational diabetes mellitus

    International Nuclear Information System (INIS)

    Xu Yongle; Yang Weiwen; Pu Xiangke

    2006-01-01

    Objectives; To research the correlation between insulin-like growth factor I (IGF-I), insulin and gestational diabetes mellitus (GDM). Methods: Thirty cases of GDM are taken as the GDM group. Thirty cases of normal pregnant women were taken as the control group. The insulin in maternal serum of these two groups were measured at 31 ± 1 weeks gestational age by radioimmunity. The IGF-I in maternal serum at 31 ± 1 weeks gestational age and IGF-I in umbilical serum at term delivery were measured by ELISA. results: There was no significant difference in IGF-I level in maternal serum between the GDM group and the control group (P>0.05) and there was significant difference between these two groups maternal LnIRI, IGF-I in umbilical serum and weight of newborn baby (P<0.01). In the GDM group, the IGF-I in maternal serum positively correlated with the LnIRI (r=0.424, P<0.05) and IGF-I in umbilical serum positively correlated with the weight of new-born baby (r=0.434, P<0.05). Conclusion: GDM has serious insulin resistance. The IGF-I in maternal serum correlated with the IR in GDM. IGF-I in umbilical serum plays a role in the pathology and physiology process of fetal macrosomia. Abnormality of the axis of growth hormone-insulin-insulin-like growth factor caused by IGF-I might be through the way of insulin resistance, and GDM is resulted. (authors)

  1. Effects of octreotide on insulin-like growth factor I and metabolic indices in growth hormone-treated growth hormone-deficient patients

    DEFF Research Database (Denmark)

    Laursen, Torben; Jørgensen, Jens Otto Lunde; Ørskov, Hans

    1993-01-01

    Abstract Animals studies have demonstrated that in addition to inhibiting growth hormone (GH) secretion octreotide inhibits in a direct manner hepatic or peripheral insulin-like growth factor I (IGF-I) generation. To test this hypothesis in humans we studied ten GH-deficient patients with frequent...

  2. Effect of Insulin Infusion on insulin-like growth factor I (IGF-I) during Hemodialysis

    DEFF Research Database (Denmark)

    Reinhard, Mark; Frystyk, Jan; Bjerre, Mette

    2012-01-01

    Background: Hemodialysis (HD) is a catabolic procedure probably contributing to the high frequency of protein-energy wasting among patients on maintenance HD. The aim was to investigate the effect of insulin infusion on insulin-like growth factor I (IGF-I) during HD compared with a meal alone...... infusion and followed by the only meal allowed during the study. Results: Data are presented as mean±SD. From baseline to end of HD session we observed an overall increase in both serum bioactive IGF-I (from 0.83±0.27 to 1.01±0.34 µg/L, p... in the change between the groups (p=0.43). Conclusion: A meal at the beginning of a HD session leads to an increase in bioactive IGF-I thereby assumingly counteracting the catabolic effects of HD. However, according to changes in bioactive IGF-I neither glucose nor glucose-insulin infusion during HD appear...

  3. Changing the insulin receptor to possess insulin-like growth factor I ligand specificity

    International Nuclear Information System (INIS)

    Andersen, A.S.; Kjeldsen, T.; Wiberg, F.C.; Christensen, P.M.; Rasmussen, J.S.; Norris, K.; Moeller, K.B.; Moeller, N.P.H.

    1990-01-01

    To examine the role of the N-terminal part of the insulin-like growth factor I (IGF-I) receptor and insulin receptor in determining ligand specificity, the authors prepared an expression vector encoding a hybrid receptor where exon 1 (encoding the signal peptide and seven amino acids of the α-subunit), exon 2, and exon 3 of the insulin receptor were replaced with the corresponding IGF-I receptor cDNA (938 nucleotides). To allow direct quantitative comparison of the binding capabilities of this hybrid receptor with those of the human IGF-I receptor and the insulin receptor, all three receptors were expressed in baby hamster kidney (BHK) cells as soluble molecules and partially purified before characterization. The hybrid IGF-I/insulin receptor bound IGF-I with an affinity comparable to that of the wild-type IGF-I receptor. In contrast, the hybrid receptor no longer displayed high-affinity binding of insulin. These results directly demonstrate that it is possible to change the specificity of the insulin receptor to that of the IGF-I receptor and, furthermore, that the binding specificity for IGF-I is encoded within the nucleotide sequence from 135 to 938 of the IGF-I receptor cDNA. Since the hybrid receptor only bound insulin with low affinity, the insulin binding region is likely to be located within exons 2 and 3 of the insulin receptor

  4. Insulin-like growth factor I/somatomedin C: a potent inducer of oligodendrocyte development

    International Nuclear Information System (INIS)

    McMorris, F.A.; Smith, T.M.; DeSalvo, S.; Furlanetto, R.W.

    1986-01-01

    Cell cultures established from cerebrum of 1-day-old rats were used to investigate hormonal regulation of the development of oligodendrocytes, which synthesize myelin in the central nervous system. The number of oligodendrocytes that developed was preferentially increased by insulin, or by insulin-like growth factor I (IGF-I), also known as somatomedin C. High concentrations of insulin were required for substantial induction of oligodendrocyte development, whereas only 3.3 ng of IGF-I per ml was needed for a 2-fold increase in oligodendrocyte numbers. At an IGF-I concentration of 100 ng/ml, oligodendrocyte numbers were increased 6-fold in cultures grown in the presence of 10% fetal bovine serum, or up to 60-fold in cultures maintained in serum-free medium. IGF-I produced less than a 2-fold increase in the number of nonoligodendroglial cells in the same cultures. Type I IGF receptors were identified on oligodendrocytes and on a putative oligodendrocyte precursor cell population identified by using mouse monoclonal antibody A2B5. Radioligand binding assays were done. These results indicate that IGF-I is a potent inducer of oligodendrocyte development and suggest a possible mechanism based on IGF deficiency for the hypomyelination that results from early postnatal malnutrition

  5. Autoinhibition of the insulin-like growth factor I receptor by the juxtamembrane region.

    Science.gov (United States)

    Craddock, Barbara P; Cotter, Christopher; Miller, W Todd

    2007-07-10

    The juxtamembrane (JM) regions of several receptor tyrosine kinases are involved in autoinhibitory interactions that maintain the low basal activity of the receptors; mutations can give rise to constitutive kinase activity and signaling. In this report, we show that the JM region of the human insulin-like growth factor I receptor (IGF1R) plays a role in kinase regulation. We mutated JM residues that were conserved in this subfamily of receptor tyrosine kinases, and expressed and purified the cytoplasmic domains using the Sf9/baculovirus system. We show that a kinase-proximal mutation (Y957F) and (to a lesser extent) a mutation in the central part of the JM region (N947A) increase the autophosphorylation activity of the kinase. Steady-state kinetic measurements show the mutations cause an increase in V(max) for phosphorylation of peptide substrates. When the holoreceptors were expressed in fibroblasts derived from IGF1R-deficient mice, the Y957F mutation led to a large increase in basal and in IGF1-stimulated receptor autophosphorylation. Together, these data demonstrate that the JM region of IGF1R plays an important role in limiting the basal activity of the receptor.

  6. Paclitaxel and trastuzumab treatment affects insulin growth factor I expression in breast cancer cell lines

    Directory of Open Access Journals (Sweden)

    Yu-Xian Qian

    2015-12-01

    Full Text Available Breast cancer is the most common type of cancers and second primary cause of death among women. Insulin-like growth factor I (IGF-1 signaling pathway plays a vital role in cancer cell survival, proliferation, chemotaxis and angiogenesis. In this study, the effect of combination of two drugs, paclitaxel and trastuzumab on IGF signaling and cell cycle arrest in breast cancer cell lines, T47D and Hs0578T were explored. The interaction of paclitaxel and trastuzumab on IGF-1 signaling pathway was studied with IGF-1 and phosphoinositide 3-kinase inhibitor, LY294002. The protein expression of IGF signaling molecules were reduced in the drug treated cancer cells. LY294002 and IGF-1 with paclitaxel and trastuzumab treatment inhibited phosphorylated Akt. During G0/G1 phase, cell cycle arrest and accumulation of apoptotic cells were observed in drug treated cancer cells. The synergistic effect of paclitaxel and trastuzumab decreased the multiplication of breast cancer cells by altering the expression of IGF-I signaling molecules. This combination proves to be one of the useful methods to treat breast cancer.

  7. Changing the insulin receptor to possess insulin-like growth factor I ligand specificity

    Energy Technology Data Exchange (ETDEWEB)

    Andersen, A.S.; Kjeldsen, T.; Wiberg, F.C.; Christensen, P.M.; Rasmussen, J.S.; Norris, K.; Moeller, K.B.; Moeller, N.P.H. (Biopharmaceuticals Div., Bagsvaerd (Denmark))

    1990-08-14

    To examine the role of the N-terminal part of the insulin-like growth factor I (IGF-I) receptor and insulin receptor in determining ligand specificity, the authors prepared an expression vector encoding a hybrid receptor where exon 1 (encoding the signal peptide and seven amino acids of the {alpha}-subunit), exon 2, and exon 3 of the insulin receptor were replaced with the corresponding IGF-I receptor cDNA (938 nucleotides). To allow direct quantitative comparison of the binding capabilities of this hybrid receptor with those of the human IGF-I receptor and the insulin receptor, all three receptors were expressed in baby hamster kidney (BHK) cells as soluble molecules and partially purified before characterization. The hybrid IGF-I/insulin receptor bound IGF-I with an affinity comparable to that of the wild-type IGF-I receptor. In contrast, the hybrid receptor no longer displayed high-affinity binding of insulin. These results directly demonstrate that it is possible to change the specificity of the insulin receptor to that of the IGF-I receptor and, furthermore, that the binding specificity for IGF-I is encoded within the nucleotide sequence from 135 to 938 of the IGF-I receptor cDNA. Since the hybrid receptor only bound insulin with low affinity, the insulin binding region is likely to be located within exons 2 and 3 of the insulin receptor.

  8. Prognostic value of insulin- like growth factor-I receptor expression in renal cell carcinoma

    Directory of Open Access Journals (Sweden)

    Sichani Mehrdad

    2010-01-01

    Full Text Available The Insulin-Like growth factor-I receptor (IGF-IR, a tyrosine-kinas receptor over expressed in many tumor cell lines and in some human tumors, plays a critical role in trans-formation, tumorigenicity and metastasis. The aim of the present study is to investigate the role of IGF-IR expression as a prognostic factor in RCC. This study was conducted in a historical cohort of 82 patients who had RCC treated with radical nephrectomy from 1994 to 2005. Specimens were reevaluated with regard to histological subtype, nuclear grade, stage and IGF-IR expression. The IGF-IR stain was semi- quantitatively evaluated using the Allred score system. Kaplan-Meier analysis demonstrated a significant positive correlation between Fuhrman nuclear grade and IGF-IR Allred score (P< 0.0001. Survival in patients with score IGF-I ≤ 4 was 90.21 month and in patients with score IGF-1R> 4 was 33.39 month (P Value < 0.0001. Cox regression analysis in-dicated that expression of IGF-IR is a prognostic factor in patients with RCC (P Value < 0.0001, odds Ratio = 2.38. In conclusion, a statistically significant correlation was demonstrated between IGF-IR expression and Fuhrman nuclear grading and survival in patients with RCC. In stage-by-stage and grade-by-grade analysis; however, it seems that we cannot consider IGF-IR as an inde-pendent prognostic factor.

  9. Prognostic value of insulin- like growth factor-I receptor expression in renal cell carcinoma.

    Science.gov (United States)

    Sichani, Mehrdad Mohammadi; Yazdi, Fateme Sarreshtedar; Moghaddam, Noushin Afshar; Chehrei, Ali; Kabiri, Mahmud; Naeimi, Amin; Taheri, Diana

    2010-01-01

    The insulin-like growth factor-I receptor (IGF-IR), a tyrosine kinase receptor over expressed in many tumor cell lines and in some human tumors, plays a critical role in transformation, tumorigenicity and metastasis. The aim of the present study is to investigate the role of IGF-IR expression as a prognostic factor in RCC. This study was conducted in a historical cohort of 82 patients who had RCC treated with radical nephrectomy from 1994 to 2005. Specimens were reevaluated with regard to histological subtype, nuclear grade, stage and IGF-IR expression. The IGF-IR stain was semi-quantitatively evaluated using the Allred score system. Kaplan-Meier analysis demonstrated a significant positive correlation between Fuhrman nuclear grade and IGF-IR Allred score (P 4 was 33.39 month (P Value < 0.0001). Cox regression analysis indicated that expression of IGF-IR is a prognostic factor in patients with RCC (P Value < 0.0001, odds Ratio = 2.38). In conclusion, a statistically significant correlation was demonstrated between IGF-IR expression and Fuhrman nuclear grading and survival in patients with RCC. In stage-by-stage and grade-by-grade analysis; however, it seems that we cannot consider IGF-IR as an independent prognostic factor.

  10. Low serum insulin-like growth factor I is associated with increased risk of ischemic heart disease

    DEFF Research Database (Denmark)

    Juul, Anders; Scheike, Thomas Harder; Davidsen, Michael

    2002-01-01

    Insulin-like growth factor I (IGF-I) has been suggested to be involved in the pathogenesis of atherosclerosis. We hypothesize that low IGF-I and high IGFBP-3 levels might be associated with increased risk of ischemic heart disease (IHD).......Insulin-like growth factor I (IGF-I) has been suggested to be involved in the pathogenesis of atherosclerosis. We hypothesize that low IGF-I and high IGFBP-3 levels might be associated with increased risk of ischemic heart disease (IHD)....

  11. Little effects of Insulin-like Growth Factor-I on testicular atrophy induced by hypoxia

    Directory of Open Access Journals (Sweden)

    Casares Amelia

    2006-02-01

    Full Text Available Abstract Background Insulin-like Growth Factor-I (IGF-I supplementation restores testicular atrophy associated with advanced liver cirrhosis that is a condition of IGF-I deficiency. The aim of this work was to evaluate the effect of IGF-I in rats with ischemia-induced testicular atrophy (AT without liver disease and consequently with normal serum level of IGF-I. Methods Testicular atrophy was induced by epinephrine (1, 2 mg/Kg intra-scrotal injection five times per week during 11 weeks. Then, rats with testicular atrophy (AT were divided into two groups (n = 10 each: untreated rats (AT receiving saline sc, and AT+IGF, which were treated with IGF-I (2 μg.100 g b.w.-1.day-1, sc. for 28d. Healthy controls (CO, n = 10 were studied in parallel. Animals were sacrificed on day 29th. Hypophyso-gonadal axis, IGF-I and IGFBPs levels, testicular morphometry and histopathology, immuno-histochemical studies and antioxidant enzyme activity phospholipid hydroperoxide glutathione peroxidase (PHGPx were assessed. Results Compared to controls, AT rats displayed a reduction in testicular size and weight, with histological testicular atrophy, decreased cellular proliferation and transferrin expression, and all of these alterations were slightly improved by IGF-I at low doses. IGF-I therapy increased signifincantly steroidogenesis and PHGPx activity (p Conclusion In testicular atrophy by hypoxia, condition without IGF-I deficiency, IGF-treatment induces only partial effects. These findings suggest that IGF-I therapy appears as an appropriate treatment in hypogonadism only when this is associated to conditions of IGF-I deficiency (such as Laron Syndrom or liver cirrhosis.

  12. Insulin-like growth factor I has independent effects on bone matrix formation and cell replication

    International Nuclear Information System (INIS)

    Hock, J.M.; Centrella, M.; Canalis, E.

    1988-01-01

    The effects of insulin-like growth factor-I (IGF-I) and insulin on bone matrix synthesis and bone cell replication were studied in cultured 21-day-old fetal rat calvariae. Histomorphometry techniques were developed to measure the incorporation of [2,3- 3 H]proline and [methyl- 3 H]thymidine into bone matrix and bone cell nuclei, respectively, using autoradiographs of sagittal sections of calvariae cultured with IGF-I, insulin, or vehicle for up to 96 h. To confirm an effect on bone formation, IGF-I was also studied for its effects on [ 3 H]proline incorporation into collagenase-digestible protein (CDP) and noncollagen protein and on [ 3 H]thymidine incorporation into acid-precipitable material (DNA). IGF-I at 10(-9)-10(-7) M significantly increased the rate of bone matrix apposition and CDP after 24 h by 45-50% and increased cell labeling by 8-fold in the osteoprogenitor cell zone, by 4-fold in the osteoblast cell zone, and by 2-fold in the periosteal fibroblast zone. Insulin at 10(-9)-10(-6) M also increased matrix apposition rate and CDP by 40-50%, but increased cell labeling by 2-fold only at a concentration of 10(-7) M or higher and then only in the osteoprogenitor cell zone. When hydroxyurea was added to IGF-I-treated bones, the effects of IGF-I on DNA synthesis were abolished, but the increase in bone matrix apposition induced by IGF-I was only partly diminished. In conclusion, IGF-I stimulates matrix synthesis in calvariae, an effect that is partly, although not completely, dependent on its stimulatory effect on DNA synthesis

  13. Dihydrotestosterone inhibits hair growth in mice by inhibiting insulin-like growth factor-I production in dermal papillae.

    Science.gov (United States)

    Zhao, Juan; Harada, Naoaki; Okajima, Kenji

    2011-10-01

    We demonstrated that insulin-like growth factor-I (IGF-I) production in dermal papillae was increased and hair growth was promoted after sensory neuron stimulation in mice. Although the androgen metabolite dihydrotestosterone (DHT) inhibits hair growth by negatively modulating growth-regulatory effects of dermal papillae, relationship between androgen metabolism and IGF-I production in dermal papillae is not fully understood. We examined whether DHT inhibits IGF-I production by inhibiting sensory neuron stimulation, thereby preventing hair growth in mice. Effect of DHT on sensory neuron stimulation was examined using cultured dorsal root ganglion (DRG) neurons isolated from mice. DHT inhibits calcitonin gene-related peptide (CGRP) release from cultured DRG neurons. The non-steroidal androgen-receptor antagonist flutamide reversed DHT-induced inhibition of CGRP release. Dermal levels of IGF-I and IGF-I mRNA, and the number of IGF-I-positive fibroblasts around hair follicles were increased at 6h after CGRP administration. DHT administration for 3weeks decreased dermal levels of CGRP, IGF-I, and IGF-I mRNA in mice. Immunohistochemical expression of IGF-I and the number of proliferating cells in hair follicles were decreased and hair re-growth was inhibited in animals administered DHT. Co-administration of flutamide and CGRP reversed these changes induced by DHT administration. These observations suggest that DHT may decrease IGF-I production in dermal papillae by inhibiting sensory neuron stimulation through interaction with the androgen receptor, thereby inhibiting hair growth in mice. Copyright © 2011 Elsevier Ltd. All rights reserved.

  14. Systemic treatment with epidermal growth factor but not insulin-like growth factor I decreases the involution of the prostate in castrated rats

    DEFF Research Database (Denmark)

    Tørring, N; Vinter-Jensen, L; Sørensen, Flemming Brandt

    2000-01-01

    Epidermal growth factor (EGF) and insulin-like growth factor I (IGF-I) are strong inducers of proliferation to prostate cells cultured in serum-free medium. Accordingly we wanted to study the growth of the prostate gland in castrated rats after treatment with EGF, IGF-I and testosterone. Castrated...

  15. Chronic alterations in growth hormone/insulin-like growth factor-I signaling lead to changes in mouse tendon structure

    DEFF Research Database (Denmark)

    Nielsen, R H; Clausen, N M; Schjerling, P

    2014-01-01

    RNA expression (targets: GAPDH, RPLP0, IGF-IEa, IGF-IR, COL1A1, COL3A1, TGF-β1, TGF-β2, TGF-β3, versican, scleraxis, tenascin C, fibronectin, fibromodulin, decorin) in the Achilles tendon, and the mRNA expression was also measured in calf muscle (same targets as tendon plus IGF-IEb, IGF-IEc). We found that GHR......The growth hormone/insulin-like growth factor-I (GH/IGF-I) axis is an important stimulator of collagen synthesis in connective tissue, but the effect of chronically altered GH/IGF-I levels on connective tissue of the muscle-tendon unit is not known. We studied three groups of mice; 1) giant......-/- mice had significantly lower collagen fibril volume fraction in Achilles tendon, as well as decreased mRNA expression of IGF-I isoforms and collagen types I and III in muscle compared to CTRL. In contrast, the mRNA expression of IGF-I isoforms and collagens in bGH mice was generally high in both tendon...

  16. A Concerted Action Of Estradiol And Insulin Like Growth Factor I Underlies Sex Differences In Mood Regulation By Exercise.

    Science.gov (United States)

    Munive, Victor; Santi, Andrea; Torres-Aleman, Ignacio

    2016-05-12

    Mood homeostasis present sexually dimorphic traits which may explain sex differences in the incidence of mood disorders. We explored whether diverse behavioral-setting components of mood may be differentially regulated in males and females by exercise, a known modulator of mood. We found that exercise decreases anxiety only in males. Conversely, exercise enhanced resilience to stress and physical arousal, two other important components of mood, only in females. Because exercise increases brain input of circulating insulin-like growth factor I (IGF-I), a potent modulator of mood, we explored whether sex-specific actions of exercise on mood homeostasis relate to changes in brain IGF-I input. We found that exercise increased hippocampal IGF-I levels only in cycling females. Underlying mechanism involved activation of estrogen (E2) receptors in brain vessels that led to increased uptake of serum IGF-I as E2 was found to stimulate IGF-I uptake in brain endothelial cells. Indeed, modulatory effects of exercise on mood were absent in female mice with low serum IGF-I levels or after either ovariectomy or administration of an E2 receptor antagonist. These results suggest that sex-specific brain IGF-I responses to physiological stimuli such as exercise contribute to dimorphic mood homeostasis that may explain sex differences in affective disorders.

  17. Hormones and diet: low insulin-like growth factor-I but normal bioavailable androgens in vegan men

    Science.gov (United States)

    Allen, N E; Appleby, P N; Davey, G K; Key, T J

    2000-01-01

    Mean serum insulin-like growth factor-I was 9% lower in 233 vegan men than in 226 meat-eaters and 237 vegetarians (P = 0.002). Vegans had higher testosterone levels than vegetarians and meat-eaters, but this was offset by higher sex hormone binding globulin, and there were no differences between diet groups in free testosterone, androstanediol glucuronide or luteinizing hormone. © 2000 Cancer Research Campaign PMID:10883675

  18. Cleavage factor I links transcription termination to DNA damage response and genome integrity maintenance in Saccharomyces cerevisiae.

    Directory of Open Access Journals (Sweden)

    Hélène Gaillard

    2014-03-01

    Full Text Available During transcription, the nascent pre-mRNA undergoes a series of processing steps before being exported to the cytoplasm. The 3'-end processing machinery involves different proteins, this function being crucial to cell growth and viability in eukaryotes. Here, we found that the rna14-1, rna15-1, and hrp1-5 alleles of the cleavage factor I (CFI cause sensitivity to UV-light in the absence of global genome repair in Saccharomyces cerevisiae. Unexpectedly, CFI mutants were proficient in UV-lesion repair in a transcribed gene. DNA damage checkpoint activation and RNA polymerase II (RNAPII degradation in response to UV were delayed in CFI-deficient cells, indicating that CFI participates in the DNA damage response (DDR. This is further sustained by the synthetic growth defects observed between rna14-1 and mutants of different repair pathways. Additionally, we found that rna14-1 suffers severe replication progression defects and that a functional G1/S checkpoint becomes essential in avoiding genetic instability in those cells. Thus, CFI function is required to maintain genome integrity and to prevent replication hindrance. These findings reveal a new function for CFI in the DDR and underscore the importance of coordinating transcription termination with replication in the maintenance of genomic stability.

  19. The insulin-like growth factor I system: physiological and pathophysiological implication in cardiovascular diseases associated with metabolic syndrome.

    Science.gov (United States)

    Ren, Jun; Anversa, Piero

    2015-02-15

    Metabolic syndrome is a cluster of risk factors including obesity, dyslipidemia, hypertension, and insulin resistance. A number of theories have been speculated for the pathogenesis of metabolic syndrome including impaired glucose and lipid metabolism, lipotoxicity, oxidative stress, interrupted neurohormonal regulation and compromised intracellular Ca(2+) handling. Recent evidence has revealed that adults with severe growth hormone (GH) and insulin-like growth factor I (IGF-1) deficiency such as Laron syndrome display increased risk of stroke and cardiovascular diseases. IGF-1 signaling may regulate contractility, metabolism, hypertrophy, apoptosis, autophagy, stem cell regeneration and senescence in the heart to maintain cardiac homeostasis. An inverse relationship between plasma IGF-1 levels and prevalence of metabolic syndrome as well as associated cardiovascular complications has been identified, suggesting the clinical promises of IGF-1 analogues or IGF-1 receptor activation in the management of metabolic and cardiovascular diseases. However, the underlying pathophysiological mechanisms between IGF-1 and metabolic syndrome are still poorly understood. This mini-review will discuss the role of IGF-1 signaling cascade in the prevalence of metabolic syndrome in particular the susceptibility to overnutrition and sedentary life style-induced obesity, dyslipidemia, insulin resistance and other features of metabolic syndrome. Special attention will be dedicated in IGF-1-associated changes in cardiac responses in various metabolic syndrome components such as insulin resistance, obesity, hypertension and dyslipidemia. The potential risk of IGF-1 and IGF-1R stimulation such as tumorigenesis is discussed. Therapeutic promises of IGF-1 and IGF-1 analogues including mecasermin, mecasermin rinfabate and PEGylated IGF-1 will be discussed. Copyright © 2014 Elsevier Inc. All rights reserved.

  20. Massive weight loss restores 24-hour growth hormone release profiles and serum insulin-like growth factor-I levels in obese subjects

    DEFF Research Database (Denmark)

    Rasmussen, M H; Hvidberg, A; Juul, A

    1995-01-01

    In the present study, we 1) determined whether the impaired spontaneous 24-h GH secretion as well as the blunted GH response to provocative testing in obese subjects are persistent disorders or transient defects reversed with weight loss and 2) investigated 24-h urinary GH excretion and basal...... levels of insulin-like growth factor-I (IGF-I), IGF-binding protein-3 (IGFBP-3), as well as insulin in obese subjects before and after a massive weight loss. We studied 18 obese subjects (age, 26 +/- 1 yr; body mass index, 40.9 +/- 1.1 kg/m2); 18 normal age-, and sex-matched control subjects; and 9...... reversible defects in 24-h spontaneous GH release profiles, basal IGF-I levels, and the IGF-I/IGFBP-3 molar ratio in obese subjects. The recovery of the 24-h GH release points to an acquired transient defect rather than a persistent preexisting disorder....

  1. Regulation of insulin-like growth factor I transcription by cyclic adenosine 3',5'-monophosphate (cAMP) in fetal rat bone cells through an element within exon 1: protein kinase A-dependent control without a consensus AMP response element

    Science.gov (United States)

    McCarthy, T. L.; Thomas, M. J.; Centrella, M.; Rotwein, P.

    1995-01-01

    Insulin-like growth factor I (IGF-I) is a locally synthesized anabolic growth factor for bone. IGF-I synthesis by primary fetal rat osteoblasts (Ob) is stimulated by agents that increase the intracellular cAMP concentration, including prostaglandin E2 (PGE2). Previous studies with Ob cultures demonstrated that PGE2 enhanced IGF-I transcription through selective use of IGF-I promoter 1, with little effect on IGF-I messenger RNA half-life. Transient transfection of Ob cultures with an array of promoter 1-luciferase reporter fusion constructs has now allowed localization of a potential cis-acting promoter element(s) responsible for cAMP-stimulated gene expression to the 5'-untranslated region (5'-UTR) of IGF-I exon 1, within a segment lacking a consensus cAMP response element. Our evidence derives from three principal observations: 1) a transfection construct containing only 122 nucleotides (nt) of promoter 1 and 328 nt of the 5'-UTR retained full PGE2-stimulated reporter expression; 2) maximal PGE2-driven reporter expression required the presence of nt 196 to 328 of exon 1 when tested within the context of IGF-I promoter 1; 3) cotransfection of IGF-I promoter-luciferase-reporter constructs with a plasmid encoding the alpha-isoform of the catalytic subunit of murine cAMP-dependent protein kinase (PKA) produced results comparable to those seen with PGE2 treatment, whereas cotransfection with a plasmid encoding a mutant regulatory subunit of PKA that cannot bind cAMP blocked PGE2-induced reporter expression. Deoxyribonuclease I footprinting of the 5'-UTR of exon 1 demonstrated protected sequences at HS3A, HS3B, and HS3D, three of six DNA-protein binding sites previously characterized with rat liver nuclear extracts. Of these three regions, only the HS3D binding site is located within the functionally identified hormonally responsive segment of IGF-I exon 1. These results directly implicate PKA in the control of IGF-I gene transcription by PGE2 and identify a segment of

  2. Differential expression of insulin like growth factor I and other fibroblast mitogens in porcine colostrum and milk

    Energy Technology Data Exchange (ETDEWEB)

    Tan, T.J.; Simmen, R.C.M.; Simmen, F.A.

    1987-05-01

    Sow mammary secretions contain at least 3 distinct growth factor activities, distinguished by their size and relative abundance in colostrum or later milk. Gel filtration of colostrum in Sephadex G-200 columns, followed by acid-ethanol extraction and radioimmunoassay (RIA) for insulin like growth factor I (IGF-I) revealed high levels of this factor in the 150K and 50K MW regions, characteristic of IGF-I: binding protein complexes. Acid treatment of these fractions yielded free IGF-I peptide (7.5K). Parallel mitogen assays with a fibroblast cell line (AKR-2B) demonstrated a predominant peak of high MW activity (sow colostral growth factor-I, SCGF-I) eluting near the column void volume (MW > 150K). Treatment of SCGF-I with 1M acetic acid resulted in a size reduction of the mitogenic activity (MW < 10K), suggesting association of SCGF-I with a binding protein. The SCGF-I peptide was noncompetitive in IGF-I RIA, was distinct in MW from free IGF-I, and was not mitogenic for chick embryo fibroblasts. Sow milk contains less IGF-I and SCGF-I but does display a predominant peak of small MW (approx. 3K) AKR-2B activity. The changes in expression of these growth factors during lactation may reflect differing roles in lactogenesis and/or neonatal growth and development.

  3. Studies on binding and mitogenic effect of insulin and insulin-like growth factor I in glomerular mesangial cells

    International Nuclear Information System (INIS)

    Conti, F.G.; Striker, L.J.; Lesniak, M.A.; MacKay, K.; Roth, J.; Striker, G.E.

    1988-01-01

    The mesangial cells are actively involved in regulating glomerular hemodynamics. Their overlying endothelium is fenestrated; therefore, these cells are directly exposed to plasma substances, including hormones such as insulin and insulin-like growth factor I (IGF-I). These peptides may contribute to the mesangial sclerosis and cellular hyperplasia that characterize diabetic glomerulopathy. We report herein the characterization of the receptors and the mitogenic effects of IGF-I and insulin on mouse glomerular mesangial cells in culture. The IGF-I receptor was characterized on intact cells. The Kd of the IGF-I receptor was 1.47 X 10(-9) M, and the estimated number of sites was 64,000 receptors/cell. The binding was time, temperature, and pH dependent, and the receptor showed down-regulation after exposure to serum. The expression of the receptor did not change on cells at different densities. The specific binding for insulin was too low to allow characterization of the insulin receptor on intact cells. However, it was possible to identify the insulin receptor in a wheat germ agglutinin-purified preparation of solubilized mesangial cells. This receptor showed the characteristic features of the insulin receptor, including pH dependence of binding and a curvilinear Scatchard plot. The mitogenic effects of insulin and IGF-I on mesangial cells were measured by the incorporation of [3H]thymidine into DNA. IGF-I was more potent than insulin. The half-maximal response to IGF-I stimulation occurred at 1.3 X 10(-10) M, and a similar increase with insulin was observed at concentrations in the range of 10(-7) M, suggesting that this insulin action was mediated through the IGF-I receptor. These data show that the mouse microvascular smooth muscle cells of the glomerulus express a cell surface receptor for IGF-I in vitro and that this peptide is a potent mitogen for these mesangial cells

  4. Regulation of REDD1 by Insulin-like Growth Factor-I in Skeletal Muscle and Myotubes

    Science.gov (United States)

    Frost, Robert A.; Huber, Danuta; Pruznak, Anne; Lang, Charles H.

    2012-01-01

    Insulin-like growth factor-I (IGF-I) is a major anabolic hormone for skeletal muscle and a potent stimulus for protein synthesis and translation initiation. Recent studies suggest that translation can be inhibited by over expression of the mammalian target of rapamycin (mTOR) repressor REDD1. The purpose of the present study was to determine whether IGF-I alters the expression of REDD1 and whether this is associated with a concomitant change in protein synthesis in vitro. Subcutaneous injection of IGF-I or intravenous delivery of insulin for 3–4 h increased REDD1 mRNA in skeletal muscle 7- to10-fold. A 3-fold increase in REDD1 was observed when C2C12 myotubes were treated with IGF-I. REDD1 protein continued to be expressed for up to 24 h after addition of IGF-I to cells. Withdrawal of IGF-I from myotubes lead to a rapid loss of REDD1 protein content. IGF-I-induced REDD1 mRNA and protein expression were prevented by inhibitors of transcription and translation. IGF-I had an additive effect with dexamethasone (Dex) on REDD1 protein content in myotubes. The PI3K inhibitor LY294002 blocked IGF-I but not Dex induced REDD1. IGF-I also stimulated REDD1 promoter activity. Although REDD1 protein was elevated 5–6 h after addition of IGF-I to myotubes, protein synthesis measured during this 1 h window was paradoxically greater in myotubes expressing more REDD1. In contrast to the IGF-I induced increase in REDD1 mRNA, REDD2 mRNA was decreased by IGF-I. We conclude that IGF-I stimulates REDD1 expression in skeletal muscle and myotubes but under these conditions the REDD1 response is not sufficient to repress protein synthesis. PMID:19795384

  5. Circulating levels of insulin-like growth factor-I (IGF-I correlate with disease status in leprosy

    Directory of Open Access Journals (Sweden)

    Rodrigues Luciana

    2011-12-01

    Full Text Available Abstract Background Caused by Mycobacterium leprae (ML, leprosy presents a strong immune-inflammatory component, whose status dictates both the clinical form of the disease and the occurrence of reactional episodes. Evidence has shown that, during the immune-inflammatory response to infection, the growth hormone/insulin-like growth factor-I (GH/IGF-I plays a prominent regulatory role. However, in leprosy, little, if anything, is known about the interaction between the immune and neuroendocrine systems. Methods In the present retrospective study, we measured the serum levels of IGF-I and IGBP-3, its major binding protein. These measurements were taken at diagnosis in nonreactional borderline tuberculoid (NR BT, borderline lepromatous (NR BL, and lepromatous (NR LL leprosy patients in addition to healthy controls (HC. LL and BL patients who developed reaction during the course of the disease were also included in the study. The serum levels of IGF-I, IGFBP-3 and tumor necrosis factor-alpha (TNF-α were evaluated at diagnosis and during development of reversal (RR or erythema nodosum leprosum (ENL reaction by the solid phase, enzyme-labeled, chemiluminescent-immunometric method. Results The circulating IGF-I/IGFBP-3 levels showed significant differences according to disease status and occurrence of reactional episodes. At the time of leprosy diagnosis, significantly lower levels of circulating IGF-I/IGFBP-3 were found in NR BL and NR LL patients in contrast to NR BT patients and HCs. However, after treatment, serum IGF-I levels in BL/LL patients returned to normal. Notably, the levels of circulating IGF-I at diagnosis were low in 75% of patients who did not undergo ENL during treatment (NR LL patients in opposition to the normal levels observed in those who suffered ENL during treatment (R LL patients. Nonetheless, during ENL episodes, the levels observed in RLL sera tended to decrease, attaining similar levels to those found in NR LL patients

  6. Cow milk consumption, insulin-like growth factor-I, and human biology: a life history approach.

    Science.gov (United States)

    Wiley, Andrea S

    2012-01-01

    To assess the life history consequences of cow milk consumption at different stages in early life (prenatal to adolescence), especially with regard to linear growth and age at menarche and the role of insulin-like growth factor I (IGF-I) in mediating a relationship among milk, growth and development, and long-term biological outcomes. United States National Health and Nutrition Examination Survey (NHANES) data from 1999 to 2004 and review of existing literature. The literature tends to support milk's role in enhancing growth early in life (prior to age 5 years), but there is less support for this relationship during middle childhood. Milk has been associated with early menarche and with acceleration of linear growth in adolescence. NHANES data show a positive relationship between milk intake and linear growth in early childhood and adolescence, but not middle childhood, a period of relatively slow growth. IGF-I is a candidate bioactive molecule linking milk consumption to more rapid growth and development, although the mechanism by which it may exert such effects is unknown. Routine milk consumption is an evolutionarily novel dietary behavior that has the potential to alter human life history parameters, especially vis-à-vis linear growth, which in turn may have negative long-term biological consequences. Copyright © 2011 Wiley Periodicals, Inc.

  7. Stimulation of myenteric plexus neurite outgrowth by insulin and insulin-like growth factors I and II.

    Science.gov (United States)

    Mulholland, M W; Romanchuk, G; Simeone, D M; Flowe, K

    1992-01-01

    A defined culture medium containing insulin, insulin-like growth factor I (IGF-I) or insulin-like growth factor II (IGF-II) supported morphological development of myenteric plexus neurons derived from neonatal guinea pigs. Insulin increased neurite outgrowth 3-fold at concentrations as low as 0.2 nM. Similar significant and dose-dependent increases in neurite outgrowth were noted with IGF-I and IGF-II. Stimulation of neurite outgrowth was abolished by exposure to cytosine arabinofuranoside, an agent toxic to non-neuronal cells, implying that trophic effects of insulin or insulin-like growth factors require the presence of non-neuronal elements in culture.

  8. The stimulatory effect of growth hormone, prolactin, and placental lactogen on beta-cell proliferation is not mediated by insulin-like growth factor-I

    DEFF Research Database (Denmark)

    Billestrup, N; Nielsen, Jens Høiriis

    1991-01-01

    The effects of GH, PRL, and placental lactogen (PL) on the proliferation of pancreatic beta-cells in vitro were studied as well as the possible effect of insulin-like growth factor-I (IGF-I) in mediating this effect. Proliferating beta-cells were identified by staining with a monoclonal antibody ...

  9. Insulin-like growth factor I enhances collagen synthesis in engineered human tendon tissue

    DEFF Research Database (Denmark)

    Herchenhan, Andreas; Bayer, Monika L.; Eliasson, Pernilla

    2015-01-01

    OBJECTIVE: Isolated human tendon cells form 3D tendon constructs that demonstrate collagen fibrillogenesis and feature structural similarities to tendon when cultured under tensile load. The exact role of circulating growth factors for collagen formation in tendon is sparsely examined. We investi...

  10. Evaluation of insulin-like growth factor-I gene polymorphism in ...

    African Journals Online (AJOL)

    Tuoyo Aghomotsegin

    2016-11-30

    Nov 30, 2016 ... (GH/IGF-I axis) is involved in these pathways and it is considered as the key in postnatal growth and. *Corresponding author. .... mammalian fertility through the regulation of many hormones which are critical for reproductive system. (Miller and Gore, 2001; Velazquez et al., 2008). Due to its important role in ...

  11. Determination of free insulin-like growth factor-I in human serum

    DEFF Research Database (Denmark)

    Frystyk, J.; Skjærbæk, C.; Ivarsen, P.

    2001-01-01

    yielded similar results in healthy subjects treated with IGF-I (n = 5) or growth hormone (n = 7) and in acromegalic patients (n = 6) before and after somatostatin analogue treatment. However, marked differences were observed in conditions with elevated IGFBP-1 and -2. In type-1 diabetics (n = 23...

  12. Infection of growing swine with porcine reproductive and respiratory syndrome virus and Mycoplasma hyopneumoniae — Effects on growth, serum metabolites, and insulin-like growth factor-I.

    OpenAIRE

    Roberts, N. Elizabeth; Almond, Glen W.

    2003-01-01

    This study evaluated the influence of concomitant infections with porcine reproductive and respiratory syndrome virus (PRRSV) and Mycoplasma hyopneumoniae on growth performance, serum metabolite concentrations, and serum insulin-like growth factor-I (IGF-I) in growing pigs. Twenty-two barrows (10 weeks of age) were treated with either an intranasal administration of PRRSV and an intratracheal infusion of M. hyopneumoniae (treatment; n = 8) or a sham inoculation with medium (sham; n = 8), or w...

  13. Growth/differentiation factor-I5 is an abundant cytokine in human seminal plasma

    Czech Academy of Sciences Publication Activity Database

    Souček, Karel; Slabáková, Eva; Ovesná, P.; Malenovská, A.; Kozubík, Alois; Hampl, Aleš

    2010-01-01

    Roč. 25, č. 12 (2010), s. 2962-2971 ISSN 0268-1161 R&D Projects: GA MZd NS9600 Institutional research plan: CEZ:AV0Z50040507; CEZ:AV0Z50040702; CEZ:AV0Z50390703 Keywords : seminal plasma * growth/differentiation factor-15 (GDF-15/MIC-1) * FOXP3 Subject RIV: BO - Biophysics Impact factor: 4.357, year: 2010

  14. Rearing Mozambique tilapia in tidally-changing salinities: Effects on growth and the growth hormone/insulin-like growth factor I axis.

    Science.gov (United States)

    Moorman, Benjamin P; Yamaguchi, Yoko; Lerner, Darren T; Grau, E Gordon; Seale, Andre P

    2016-08-01

    The growth hormone (GH)/insulin-like growth factor (IGF) axis plays a central role in the regulation of growth in teleosts and has been shown to be affected by acclimation salinity. This study was aimed at characterizing the effects of rearing tilapia, Oreochromis mossambicus, in a tidally-changing salinity on the GH/IGF axis and growth. Tilapia were raised in fresh water (FW), seawater (SW), or in a tidally-changing environment, in which salinity is switched between FW (TF) and SW (TS) every 6h, for 4months. Growth was measured over all time points recorded and fish reared in a tidally-changing environment grew significantly faster than other groups. The levels of circulating growth hormone (GH), insulin-like growth factor I (IGF-I), pituitary GH mRNA, gene expression of IGF-I, IGF-II, and growth hormone receptor 2 (GHR) in the muscle and liver were also determined. Plasma IGF-I was higher in FW and TS than in SW and TF tilapia. Pituitary GH mRNA was higher in TF and TS than in FW and SW tilapia. Gene expression of IGF-I in the liver and of GHR in both the muscle and liver changed between TF and TS fish. Fish growth was positively correlated with GH mRNA expression in the pituitary, and GHR mRNA expression in muscle and liver tissues. Our study indicates that rearing fish under tidally-changing salinities elicits a distinct pattern of endocrine regulation from that observed in fish reared in steady-state conditions, and may provide a new approach to increase tilapia growth rate and study the regulation of growth in euryhaline fish. Copyright © 2016 Elsevier Inc. All rights reserved.

  15. Systemic treatment with epidermal growth factor but not insulin-like growth factor I decreases the involution of the prostate in castrated rats

    DEFF Research Database (Denmark)

    Tørring, N; Vinter-Jensen, L; Sørensen, Flemming Brandt

    2000-01-01

    Epidermal growth factor (EGF) and insulin-like growth factor I (IGF-I) are strong inducers of proliferation to prostate cells cultured in serum-free medium. Accordingly we wanted to study the growth of the prostate gland in castrated rats after treatment with EGF, IGF-I and testosterone. Castrated...... Wistar rats were treated with growth factors (EGF 35 microg/rat per day; IGF-I 350 microg/rat per day) or testosterone (2 mg/rat per day) for 3 days either immediately after or 10 days after castration. Prostate tissue was examined by stereological and immunohistochemical techniques and by enzyme...

  16. Insulin-like growth factor I and anthropometric parameters in a Danish population

    DEFF Research Database (Denmark)

    Friedrich, N; Jørgensen, Torben; Juul, A

    2012-01-01

    During the last decade several studies indicated that low insulin-like growth factor (IGF) I levels are related to higher risk of cardiovascular disease and mortality. Obesity represents one further main cardiovascular risk factor which might also be related to IGF-I. The objective of the present...... study was to analyse the associations between anthropometric measures and IGF-I levels in a population-based sample. From the Danish cross-sectional Health2006 study 3,328 subjects (1,835 women; 1,493 men) aged 19-72 years were included in the analyses. Serum IGF-I levels were determined...

  17. Diminished concentrations of insulin-like growth factor I in cystic fibrosis

    DEFF Research Database (Denmark)

    Laursen, Erik; Juul, A; Lanng, S

    1995-01-01

    on IGF-I in cystic fibrosis are sparse and conflicting. From 1990-3, 235 of our 240 patients (114 males, 121 females, median age 16.2 years, ranged 0.1-44.0 years) had IGF-I measured once by radioimmunoassay. IGF-I was significantly reduced compared with a healthy Scandinavian control population: mean...... (-2 SD to +2 SD) IGF-I SD score was -0.97 (-3.7 to 1.7) in males and -0.67 (-3.2 to 1.9) in females. Height SD score was -0.95 (-3.3 to 1.4) in males and -0.81 (-3.2 to 1.6) in females. In patients who were still in the growth period a significant correlation of IGF-I SD score to height SD score (r...

  18. Myostatin and insulin-like growth factor I: potential therapeutic biomarkers for pompe disease.

    Directory of Open Access Journals (Sweden)

    Yin-Hsiu Chien

    Full Text Available OBJECTIVE: Myostatin and insulin-like growth factor 1 (IGF-1 are serum markers for muscle growth and regeneration. However, their value in the clinical monitoring of Pompe disease - a muscle glycogen storage disease - is not known. In order to evaluate their possible utility for disease monitoring, we assessed the levels of these serum markers in Pompe disease patients receiving enzyme replacement therapy (ERT. DESIGN: A case-control study that included 10 patients with Pompe disease and 10 gender- and age-matched non-Pompe disease control subjects was performed in a referral medical center. Average follow-up duration after ERT for Pompe disease patients was 11.7 months (range: 6-23 months. Measurements of serum myostatin, IGF-1, and creatine kinase levels were obtained, and examinations of muscle pathology were undertaken before and after ERT in the patient group. RESULTS: Compared with control subjects, Pompe disease patients prior to undergoing ERT had significantly lower serum IGF-1 levels (98.6 ng/ml vs. 307.9 ng/ml, p = 0.010 and lower myostatin levels that bordered on significance (1.38 ng/ml vs. 3.32 ng/ml, p = 0.075. After ERT, respective myostatin and IGF-1 levels in Pompe disease patients increased significantly by 129% (from 1.38 ng/ml to 3.16 ng/ml, p = 0.047 and 74% (from 98.6 ng/ml to 171.1 ng/ml, p = 0.013; these values fall within age-matched normal ranges. In contrast, myostatin and IGF-1 serum markers did not increase in age-matched controls. Follistatin, a control marker unrelated to muscle, increased in both Pompe disease patients and control subjects. At the same time, the percentage of muscle fibers containing intracytoplasmic vacuoles decreased from 80.0±26.4% to 31.6±45.3%. CONCLUSION: The increase in myostatin and IGF-1 levels in Pompe disease patients may reflect muscle regeneration after ERT. The role of these molecules as potential therapeutic biomarkers in Pompe disease and other neuromuscular

  19. Plasma leptin and insulin-like growth factor I levels during acute exacerbations of chronic obstructive pulmonary disease.

    Science.gov (United States)

    Kythreotis, Prokopis; Kokkini, Ageliki; Avgeropoulou, Stavrina; Hadjioannou, Argyro; Anastasakou, Efgenia; Rasidakis, Antonis; Bakakos, Petros

    2009-04-05

    Recent studies have provided evidence for a link between leptin and tumor necrosis factor-alpha (TNF-alpha). Insulin-like growth factor I (IGF-I) mediates the metabolic effects of growth hormone (GH). The GH axis is believed to be suppressed in chronic obstructive pulmonary disease (COPD). The aim of this study is to find out whether acute exacerbations of COPD are followed by changes in plasma leptin and insulin-like growth factor I (IGF-I) levels and furthermore, whether these changes are related to systemic inflammation. We measured serum leptin, IGF-I, TNF-alpha, interleukin 1 beta (IL-1 beta), interleukin 6 (IL-6) and interleukin 8 (IL-8) levels in 52 COPD patients with acute exacerbation on admission to hospital (Day 1) and two weeks later (Day 15). 25 healthy age-matched subjects served as controls. COPD patients were also divided into two subgroups (29 with chronic bronchitis and 23 with emphysema). Serum leptin and IGF-I were measured by radioimmunoassay and TNF-alpha, IL-1 beta, IL-6 and IL-8 were measured by ELISA. Serum leptin levels were significantly higher and serum IGF-I levels significantly lower in COPD patients on Day 1 than in healthy controls (p leptin and TNF-alpha on Day 1 (r = 0.620, p leptin levels along with decreased IGF-I levels occurred during acute exacerbations of COPD. Compared to chronic bronchitis, patients with emphysema had lower circulating IGF-I levels both at the onset of the exacerbation and two weeks later.

  20. Plasma leptin and insulin-like growth factor I levels during acute exacerbations of chronic obstructive pulmonary disease

    Directory of Open Access Journals (Sweden)

    Rasidakis Antonis

    2009-04-01

    Full Text Available Abstract Background Recent studies have provided evidence for a link between leptin and tumor necrosis factor-alpha (TNF-α. Insulin-like growth factor I (IGF-I mediates the metabolic effects of growth hormone (GH. The GH axis is believed to be suppressed in chronic obstructive pulmonary disease (COPD. The aim of this study is to find out whether acute exacerbations of COPD are followed by changes in plasma leptin and insulin-like growth factor I (IGF-I levels and furthermore, whether these changes are related to systemic inflammation. Methods We measured serum leptin, IGF-I, TNF-α, interleukin 1β (IL-1β, interleukin 6 (IL-6 and interleukin 8 (IL-8 levels in 52 COPD patients with acute exacerbation on admission to hospital (Day 1 and two weeks later (Day 15. 25 healthy age-matched subjects served as controls. COPD patients were also divided into two subgroups (29 with chronic bronchitis and 23 with emphysema. Serum leptin and IGF-I were measured by radioimmunoassay and TNF-α, IL-1β, IL-6 and IL-8 were measured by ELISA. Results Serum leptin levels were significantly higher and serum IGF-I levels significantly lower in COPD patients on Day 1 than in healthy controls (p Conclusion Inappropriately increased circulating leptin levels along with decreased IGF-I levels occured during acute exacerbations of COPD. Compared to chronic bronchitis, patients with emphysema had lower circulating IGF-I levels both at the onset of the exacerbation and two weeks later.

  1. Insulin-Like Growth Factor I Does Not Drive New Bone Formation in Experimental Arthritis.

    Directory of Open Access Journals (Sweden)

    Melissa N van Tok

    Full Text Available Insulin like growth factor (IGF-I can act on a variety of cells involved in cartilage and bone repair, yet IGF-I has not been studied extensively in the context of inflammatory arthritis. The objective of this study was to investigate whether IGF-I overexpression in the osteoblast lineage could lead to increased reparative or pathological bone formation in rheumatoid arthritis and/or spondyloarthritis respectively.Mice overexpressing IGF-I in the osteoblast lineage (Ob-IGF-I+/- line 324-7 were studied during collagen induced arthritis and in the DBA/1 aging model for ankylosing enthesitis. Mice were scored clinically and peripheral joints were analysed histologically for the presence of hypertrophic chondrocytes and osteocalcin positive osteoblasts.90-100% of the mice developed CIA with no differences between the Ob-IGF-I+/- and non-transgenic littermates. Histological analysis revealed similar levels of hypertrophic chondrocytes and osteocalcin positive osteoblasts in the ankle joints. In the DBA/1 aging model for ankylosing enthesitis 60% of the mice in both groups had a clinical score 1<. Severity was similar between both groups. Histological analysis revealed the presence of hypertrophic chondrocytes and osteocalcin positive osteoblasts in the toes in equal levels.Overexpression of IGF-I in the osteoblast lineage does not contribute to an increase in repair of erosions or syndesmophyte formation in mouse models for destructive and remodeling arthritis.

  2. A controlled study on serum insulin-like growth factor-I and urinary excretion of growth hormone in fibromyalgia

    DEFF Research Database (Denmark)

    Jacobsen, S; Main, K; Danneskiold-Samsøe, B

    1995-01-01

    It has been hypothesized that secretory deficiencies of growth hormone may play a pathophysiological role in fibromyalgia (FM). Our objective was thus to evaluate the secretion of growth hormone in FM.......It has been hypothesized that secretory deficiencies of growth hormone may play a pathophysiological role in fibromyalgia (FM). Our objective was thus to evaluate the secretion of growth hormone in FM....

  3. [Insulin-like growth factor-I and cognitive function in patients with obstructive sleep apnea syndrome].

    Science.gov (United States)

    Xu, Yan; Li, Shunwei; Huang, Xizhen; Cong, Bo

    2002-10-25

    To explore the possible biochemical mechanism of cognitive impairment in patients with obstructive sleep apnea syndrome (OSAS). Polysomnography was administered to thirty-six patients with OSAS and eighteen education and BMI-matched controls, all males aged 40 approximately 49 for 8.5 hours at night. Early next morning blood was drawn and serum insulin-like growth factor-I (IGF-I) was determined by immunoradiometric assay. Then neuropsychological tests of visual regeneration, digital symbol, comprehensive memory and digital span were conducted. The quality of sleep in the patients with OSAS was significantly worse than that of the controls. The score of visual regeneration in the patients with OSAS was 8.4 +/- 2.7, significantly lower than that in control group (11.6 +/- 1.4, P sleep duration (r = 0.598, P sleep deprivation may be the reason of the decrease of the serum IGF-I level in patients with OSAS.

  4. Local administration of insulin-like growth factor-I (IGF-I) stimulates tendon collagen synthesis in humans

    DEFF Research Database (Denmark)

    Hansen, Mette; Boesen, Anders; Holm, Lars

    2013-01-01

    Collagen is the predominant structural protein in tendons and ligaments, and can be controlled by hormonal changes. In animals, injections of insulin-like growth factor I (IGF-I) has been shown to increase collagen synthesis in tendons and ligaments and to improve structural tissue healing......, but the effect of local IGF-I administration on tendon collagen synthesis in human has not been studied. The purpose of this study was to study whether local injections of IGF-I would have a stimulating effect on tendon collagen synthesis. Twelve healthy nonsmoking men [age 62 ± 1 years (mean ± SEM), BMI 27 ± 1......] participated. Two injections of either human recombinant IGF-I (0.1 mL Increlex©) or saline (control) into each patellar tendon were performed 24-h apart, respectively. Tendon collagen fractional synthesis rate (FSR) was measured by stable isotope technique in the hours after the second injection...

  5. Enzyme-linked immunosorbent assays for insulin-like growth factor-I using six-histidine tag fused proteins

    International Nuclear Information System (INIS)

    Huang Yong; Shi Ruina; Zhong Xuefei; Wang Dan; Zhao Meiping; Li Yuanzong

    2007-01-01

    The fusion proteins of insulin-like growth factor-I (IGF-I) and six-histidine tag (IGF-I-6H, 6H-IGF-I-6H) were cloned, expressed, purified and renatured, with their immunoreaction properties and biological activities intact. The binding kinetics between these fusion proteins and anti-IGF-I antibody or anti-6H antibody were studied using surface plasmon resonance (SPR). Two enzyme-linked immunosorbent assay (ELISA) modes, which proved feasible in the measurement of human serum samples, were used to detect IGF-I with the help of the six-histidine tagged proteins. Furthermore, combining the production technique of the six-histidine tagged fusion protein with the competitive sandwich ELISA mode, using an enzyme labeled anti-6H antibody as a tracer, can be a universal immunochemical method to quantitate other polypeptides or proteins

  6. Insulin-like growth factor I enhances proenkephalin synthesis and dopamine. beta. -hydroxylase activity in adrenal chromaffin cells

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, S.P. (Univ. of South Carolina School of Medicine, Columbia (USA))

    1991-01-01

    Insulin-like growth factor I (IGF-I) increased both the contents of proenkephalin derived enkephalin-containing peptides and the activity of dopamine {beta}-hydroxylase in bovine adrenal chromaffin cells. These increases in dopamine {beta}-hydroxylase and enkephalin-containing peptides continued for at least 8 days. The half-maximal IGF-I concentration for these effects was {approximately} 1 nM, with maximal effects observed at 10-30 nM. In contrast, insulin was 1,000-fold less potent. Pretreatment of chromaffin cells with IGF-I increased the rate of ({sup 35}S)proenkephalin synthesis 4-fold compared to untreated cells. Total protein synthesis increased only 1.5-fold under these conditions. These results suggest that IGF-I may be a normal regulator of chromaffin cell function.

  7. Effects of insulin-like growth factor-I on bone metabolism in patients with liver cirrhosis

    International Nuclear Information System (INIS)

    Li Xiaohong; Gao Wenjin; Wang Mingtao; Hu Haiqiang

    2006-01-01

    To study the effects of serum insulin-like growth factor-I (IGF-I) on bone metabolism in liver cirrhosis, 44 patients with hepatic cirrhosis were divided into 3 groups according to disease severity (Child Pugh Score) and 38 healthy subjects served as controls. Serum levels of IGF-I and osteocalcin(BGP) were measured in all patients and controls. Results showed that levels of IGF-I, BGP, and BMD were lower significantly in patients with liver cirrhosis than that in controls. When the condition of cirrhosis more deteriorated, these changes became much lower significantly. Serum levels of BGP and BMD were positively correlated with IGF-I. The decreasing level of IGF-I might be an important factor causing osteoporosis in patients with liver cirrhosis. (authors)

  8. A controlled study on serum insulin-like growth factor-I and urinary excretion of growth hormone in fibromyalgia

    DEFF Research Database (Denmark)

    Jacobsen, S; Main, K; Danneskiold-Samsøe, B

    1995-01-01

    OBJECTIVE. It has been hypothesized that secretory deficiencies of growth hormone may play a pathophysiological role in fibromyalgia (FM). Our objective was thus to evaluate the secretion of growth hormone in FM. METHODS. The 24-h urinary growth hormone excretion and serum levels of insulin...

  9. Seasonal regulation of the growth hormone-insulin-like growth factor-I axis in the American black bear (Ursus americanus).

    Science.gov (United States)

    Blumenthal, Stanley; Morgan-Boyd, Rebecca; Nelson, Ralph; Garshelis, David L; Turyk, Mary E; Unterman, Terry

    2011-10-01

    The American black bear maintains lean body mass for months without food during winter denning. We asked whether changes in the growth hormone/insulin-like growth factor-I (GH-IGF-I) axis may contribute to this remarkable adaptation to starvation. Serum IGF-I levels were measured by radioimmunoassay, and IGF-binding proteins (IGFBPs) were analyzed by ligand blotting. Initial studies in bears living in the wild showed that IGF-I levels are highest in summer and lowest in early winter denning. Detailed studies in captive bears showed that IGF-I levels decline in autumn when bears are hyperphagic, continue to decline in early denning, and later rise above predenning levels despite continued starvation in the den. IGFBP-2 increased and IGFBP-3 decreased in early denning, and these changes were also reversed in later denning. Treatment with GH (0.1 mg·kg(-1)·day(-1) × 6 days) during early denning increased serum levels of IGF-I and IGFBP-3 and lowered levels of IGFBP-2, indicating that denning bears remain responsive to GH. GH treatment lowered blood urea nitrogen levels, reflecting effects on protein metabolism. GH also accelerated weight loss and markedly increased serum levels of free fatty acids and β-hydroxybutyrate, resulting in a ketoacidosis (bicarbonate decreased to 15 meq/l), which was reversed when GH was withdrawn. These results demonstrate seasonal regulation of GH/IGF-I axis activity in black bears. Diminished GH activity may promote fat storage in autumn in preparation for denning and prevent excessive mobilization and premature exhaustion of fat stores in early denning, whereas restoration of GH/IGF activity in later denning may prepare the bear for normal activity outside the den.

  10. Insulin and insulin-like growth factor I exert different effects on plasminogen activator production or cell growth in the ovine thyroid cell line OVNIS.

    Science.gov (United States)

    Degryse, B; Maisonobe, F; Hovsépian, S; Fayet, G

    1991-11-01

    Insulin and Insulin-like Growth Factor I (IGF-I) are evaluated for their capacity to affect cell proliferation and plasminogen activator (PA) activity production in an ovine thyroid cell line OVNIS. Insulin at physiological and supraphysiological doses induces cell proliferation and increases PA activity. IGF-I, which is also clearly mitogenic for these cells, surprisingly does not modulate PA activity. The results indicate that the growth promoting effect is mediated through the insulin and IGF-I receptors whereas PA activity is solely regulated via the insulin receptors.

  11. Adult and near-adult height in patients with severe insulin-like growth factor-I deficiency after long-term therapy with recombinant human insulin-like growth factor-I.

    Science.gov (United States)

    Backeljauw, Philippe F; Kuntze, Joyce; Frane, James; Calikoglu, Ali S; Chernausek, Steven D

    2013-01-01

    Treatment with recombinant human insulin-like growth factor-I (IGF-I) stimulates linear growth in children with severe IGF-I deficiency (IGFD). To evaluate the efficacy and safety of treatment with IGF-I in patients with severe IGFD treated until adult or near-adult height. Twenty-one children with severe IGFD were treated until adult or near-adult height under a predominantly open-label design. All patients were naive to IGF-I. Recombinant human IGF-I was administered subcutaneously in doses between 60 and 120 µg/kg twice daily. Nine patients received additional therapy with gonadotropin- releasing hormone (GnRH) analog for a mean period of 2.9 ± 1.8 years. Mean duration of treatment was 10.0 years. Mean height velocity increased from 3.1 cm/year prior to treatment to 7.4 cm/year during the first year of treatment. Height velocities during the subsequent years were lower, but remained above baseline for up to 12 years. Cumulative mean Δ height SD score at (near) adult height was +2. The observed mean gain in height was 13.4 cm more than had been expected without treatment. The adult height achieved by the patients also treated with GnRH analog was not different from those who received IGF-I therapy alone. There were no new safety signals identified in these patients, a subset of those previously reported. Long-term therapy with IGF-I improves adult height of patients with severe IGFD. Most patients did not bring their heights into the normal adult range. Copyright © 2013 S. Karger AG, Basel.

  12. Characteristics and reference ranges of Insulin-Like Growth Factor-I measured with a commercially available immunoassay in 724 healthy adult Caucasians

    DEFF Research Database (Denmark)

    Andreassen, Mikkel; Nielsen, Kaspar; Raymond, Ilan

    2009-01-01

    BACKGROUND AND OBJECTIVE: Measurements of Insulin-Like Growth Factor-I (IGF-I) play a pivotal role in the evaluation of the growth hormone-IGF-I axis. Due to assay variation IGF-I reference ranges are assay specific. We provide serum IGF-I reference ranges for adult men and women obtained...

  13. The effects of physical activity and fitness in adolescence on cognition in adulthood and the role of insulin-like growth factor I

    NARCIS (Netherlands)

    Ferro, D.A.; Deijen, J.B.; Koppes, L.L.; Mechelen, W. van; Twisk, J.W.; Drent, M.L.

    2016-01-01

    Background: Physical activity and fitness in adolescence may improve cognition in adulthood by increasing insulin-like growth factor I (IGF-I). Methods: As part of the Amsterdam Growth and Health Longitudinal Study, following subjects from age 13 to 42 years, physical activity and fitness of 303

  14. Serum insulin-like growth factor-I levels are associated with improved white matter recovery after traumatic brain injury.

    Science.gov (United States)

    Feeney, Claire; Sharp, David J; Hellyer, Peter J; Jolly, Amy E; Cole, James H; Scott, Gregory; Baxter, David; Jilka, Sagar; Ross, Ewan; Ham, Timothy E; Jenkins, Peter O; Li, Lucia M; Gorgoraptis, Nikos; Midwinter, Mark; Goldstone, Anthony P

    2017-07-01

    Traumatic brain injury (TBI) is a common disabling condition with limited treatment options. Diffusion tensor imaging measures recovery of axonal injury in white matter (WM) tracts after TBI. Growth hormone deficiency (GHD) after TBI may impair axonal and neuropsychological recovery, and serum insulin-like growth factor-I (IGF-I) may mediate this effect. We conducted a longitudinal study to determine the effects of baseline serum IGF-I concentrations on WM tract and neuropsychological recovery after TBI. Thirty-nine adults after TBI (84.6% male, median age = 30.5 years, 87.2% moderate-severe, median time since TBI = 16.3 months, n = 4 with GHD) were scanned twice, 13.3 months (range = 12.1-14.9) apart, and 35 healthy controls were scanned once. Symptom and quality of life questionnaires and cognitive assessments were completed at both visits (n = 33). Our main outcome measure was fractional anisotropy (FA), a measure of WM tract integrity, in a priori regions of interest: splenium of corpus callosum (SPCC) and posterior limb of internal capsule (PLIC). At baseline, FA was reduced in many WM tracts including SPCC and PLIC following TBI compared to controls, indicating axonal injury, with longitudinal increases indicating axonal recovery. There was a significantly greater increase in SPCC FA over time in patients with serum IGF-I above versus below the median for age. Only the higher IGF-I group had significant improvements in immediate verbal memory recall over time. WM recovery and memory improvements after TBI were greater in patients with higher serum IGF-I at baseline. These findings suggest that the growth hormone/IGF-I system may be a potential therapeutic target following TBI. Ann Neurol 2017;82:30-43. © 2017 The Authors Annals of Neurology published by Wiley Periodicals, Inc. on behalf of American Neurological Association.

  15. Systemic administration of insulin-like growth factor I (IGF-I) causes growth of the rat prostate

    DEFF Research Database (Denmark)

    Tørring, N; Vinter-Jensen, L; Pedersen, S B

    1997-01-01

    .01) increase in the mean wet weight of the ventral prostate. The mean weight of the dorsolateral lobe of the prostate increased by 39% (p controls. The ODC-activity in the prostate was significantly increased by IGF......-I after 3 days of treatment, and administration of IGF-I concomitantly with DFMO significantly inhibited ODC activity and the weight increase of the prostate. Stereological examination of the prostate in the IGF-I-treated animals showed growth of the epithelial component of the gland. Systemic treatment...... with EGF did not affect the mean weight of the prostate or the seminal vesicle compared to controls.CONCLUSION: The results demonstrate that treatment with IGF-I but not EGF for 7 days induces profound growth of the rat prostate and the seminal vesicle, and that the growth is dependent on an intact ODC-activity....

  16. Serum insulin-like growth factor-I (IGF-I) and growth in children born after assisted reproduction

    DEFF Research Database (Denmark)

    Kai, Claudia Mau; Main, Katharina M; Andersen, Anders Nyboe

    2006-01-01

    cohorts was normal. Our findings of subtle differences in target height attainment and serum IGF-I levels between infants born after assisted reproduction techniques and controls may not be clinically significant. However, these observations indicate that further systematic follow-up of growth and puberty......CONTEXT: Concern has been raised about the safety of assisted reproduction techniques for the offspring. OBJECTIVES: The objective of the study was to investigate postnatal growth and growth factors in children born after intra-cytoplasmatic sperm injection (ICSI) and in vitro fertilization (IVF......). DESIGN: The study had two cohorts: a population-based longitudinal infant cohort 0-36 months [236 ICSI, 173 IVF, 1530 naturally conceived (NC)], and a cross-sectional child cohort at 5 yr (68 ICSI, 67 IVF, 70 NC). INTERVENTION: Anthropometrical measurements were made at birth, 3, 18, 36 (infant cohort...

  17. Astrocytes require insulin-like growth factor I to protect neurons against oxidative injury [v1; ref status: indexed, http://f1000r.es/2lf

    Directory of Open Access Journals (Sweden)

    Laura Genis

    2014-01-01

    Full Text Available Oxidative stress is a proposed mechanism in brain aging, making the study of its regulatory processes an important aspect of current neurobiological research. In this regard, the role of the aging regulator insulin-like growth factor I (IGF-I in brain responses to oxidative stress remains elusive as both beneficial and detrimental actions have been ascribed to this growth factor. Because astrocytes protect neurons against oxidative injury, we explored whether IGF-I participates in astrocyte neuroprotection and found that blockade of the IGF-I receptor in astrocytes abrogated their rescuing effect on neurons. The protection mediated by IGF-I against oxidative stress (H2O2 in astrocytes is probably needed for these cells to provide adequate neuroprotection. Indeed, in astrocytes but not in neurons, IGF-I helps decrease the pro-oxidant protein thioredoxin-interacting protein 1 and normalizes the levels of reactive oxygen species. Furthermore, IGF-I cooperates with trophic signals produced by astrocytes in response to H2O2 such as stem cell factor (SCF to protect neurons against oxidative insult. After stroke, a condition associated with brain aging where oxidative injury affects peri-infarcted regions, a simultaneous increase in SCF and IGF-I expression was found in the cortex, suggesting that a similar cooperative response takes place in vivo. Cell-specific modulation by IGF-I of brain responses to oxidative stress may contribute in clarifying the role of IGF-I in brain aging.

  18. Astrocytes require insulin-like growth factor I to protect neurons against oxidative injury [v2; ref status: indexed, http://f1000r.es/38u

    Directory of Open Access Journals (Sweden)

    Laura Genis

    2014-04-01

    Full Text Available Oxidative stress is a proposed mechanism in brain aging, making the study of its regulatory processes an important aspect of current neurobiological research. In this regard, the role of the aging regulator insulin-like growth factor I (IGF-I in brain responses to oxidative stress remains elusive as both beneficial and detrimental actions have been ascribed to this growth factor. Because astrocytes protect neurons against oxidative injury, we explored whether IGF-I participates in astrocyte neuroprotection and found that blockade of the IGF-I receptor in astrocytes abrogated their rescuing effect on neurons. We found that IGF-I directly protects astrocytes against oxidative stress (H2O2. Indeed, in astrocytes but not in neurons, IGF-I decreases the pro-oxidant protein thioredoxin-interacting protein 1 and normalizes the levels of reactive oxygen species. Furthermore, IGF-I cooperates with trophic signals produced by astrocytes in response to H2O2 such as stem cell factor (SCF to protect neurons against oxidative insult. After stroke, a condition associated with brain aging where oxidative injury affects peri-infarcted regions, a simultaneous increase in SCF and IGF-I expression was found in the cortex, suggesting that a similar cooperative response takes place in vivo. Cell-specific modulation by IGF-I of brain responses to oxidative stress may contribute in clarifying the role of IGF-I in brain aging.

  19. Systemic administration of insulin-like growth factor I (IGF-I) causes growth of the rat prostate

    DEFF Research Database (Denmark)

    Tørring, N; Vinter-Jensen, L; Pedersen, S B

    1997-01-01

    -I after 3 days of treatment, and administration of IGF-I concomitantly with DFMO significantly inhibited ODC activity and the weight increase of the prostate. Stereological examination of the prostate in the IGF-I-treated animals showed growth of the epithelial component of the gland. Systemic treatment...

  20. The phosphatidylinositol-3 kinase pathway is not essential for insulin-like growth factor I receptor-mediated clonogenic radioresistance

    International Nuclear Information System (INIS)

    Yu, Dong; Watanabe, Hiroshi; Shibuya, Hitoshi; Miura, Masahiko

    2002-01-01

    The insulin-like growth factor I receptor (IGF-IR) is known to induce clonogenic radioresistance in cells following ionizing irradiation. To explore the downstream signaling pathways, we focused on the phosphatidylinositol-3 kinase (PI3-K) pathway, which is thought to be the primary cell survival signal originating from the receptor. For this purpose, R- cells deficient in the endogenous IGF-IR were used as a recipient of the human IGF-IR with or without mutations at potential PI3-K activation sites: NPXY 950 and Y 1316 XXM. Mutats with double mutation at Y950/Y1316 exhibited not abrogated, but reduced activation of insulin receptor substance-1 (IRS-1), PI3-K, and Akt upon IGF-I stimulation. However, the mutants had the same clonogenic radioresistance as cells with wild type (WT) receptors. Neither wortmannin nor LY294002, specific inhibitors of PI3-K, affected the radioresistance of cells with WT receptors at concentrations specific for PI3-K. Collectively, these results indicate that the PI3-K pathway is not essential for IGF-IR-mediated clonogenic radioresistance. (author)

  1. Prediction of the outcome of growth hormone provocative testing in short children by measurement of serum levels of insulin-like growth factor I and insulin-like growth factor binding protein 3

    DEFF Research Database (Denmark)

    Juul, A; Skakkebaek, N E

    1997-01-01

    Serum levels of insulin-like growth factor I (IGF-I) and insulin-like growth factor binding protein 3 (IGFBP-3) reflect the secretion of endogenous growth hormone (GH) in healthy children and exhibit little diurnal variation, which makes them potential candidates for screening of GH deficiency (G...

  2. The insulin-like growth factor-I receptor (IGF-IR) in breast cancer: biology and treatment strategies.

    Science.gov (United States)

    Motallebnezhad, Morteza; Aghebati-Maleki, Leili; Jadidi-Niaragh, Farhad; Nickho, Hamid; Samadi-Kafil, Hosein; Shamsasenjan, Karim; Yousefi, Mehdi

    2016-09-01

    Breast cancer is the most common cancer and the second leading cause of cancer-related deaths among women worldwide. Although patients are often diagnosed in the early and curable stages, the treatment of metastatic breast cancer remains a major clinical challenge. The combination of chemotherapy with new targeting agents, such as bevacizumab, is helpful in improving patient survival; however, novel treatment strategies are required to improve clinical outcomes. The insulin-like growth factor-I receptor (IGF-IR) is a tyrosine kinase cell surface receptor which is involved in the regulation of cell growth and metabolism. Previous studies have shown that activation of the IGF-IR signaling pathway promotes proliferation, survival, and metastasis of breast cancer cells. Additionally, overexpression of IGF-IR is associated with breast cancer cell resistance to anticancer therapies. Recently, IGF-IR has been introduced as a marker of stemness in breast cancer cells and there is also accumulating evidence that IGF-IR contributes to the establishment and maintenance of breast cancer epithelial-mesenchymal transition (EMT). Therefore, pharmacological or molecular targeting of IGF-IR could be a promising strategy, in the treatment of patients with breast cancer, particularly in order to circumvent the therapeutic resistance and targeting breast cancer stem/progenitors. Currently, many strategies have been developed for targeting IGF-IR, some have entered clinical trials and some are in preclinical stages for breast cancer therapy. In this review, we will first discuss on the biology of IGF-IR in an attempt to find the role of this receptor in breast cancer and then discuss about therapeutic strategies to target this receptor.

  3. Determination of insulin-like growth factor-I reference values using an immunoradiometric assay in a Brazilian adult population.

    Science.gov (United States)

    Leite, Denise B; Meirelles, Ricardo M R; Mandarim-De-Lacerda, Carlos A; Matos, Haroldo J; Santos-Filho, Sebastião D; Bernardo-Filho, Mario

    2012-01-01

    Serum levels of total insulin-like growth factor I (IGF-I) reflect endogenous growth hormone (GH) secretion in healthy adults, which makes it a good diagnostic marker for screening of GH-related disorders. Studies also have supported a possible relation between IGF-I levels and the risk and prognostic for some malignancies, besides a relation between IGF-I levels and mortality. As the determination of the IGF-I normal values for local populations is strongly desired, the aim of this investigation was to determine reference values for IGF-I using an immunoradiometric assay (IRMA) in an adult Brazilian population of Rio de Janeiro city, since there is no other study using this methodology in Brazilian population, and that this method is widely used in Brazil and worldwide. The study included samples of blood taken from 484 healthy subjects (251 men and 233 women) aged 18-70. The subjects agreed with this study, approved by the Ethical Committee of the Instituto Estadual de Hematologia Arthur de Siqueira Cavalcanti, Rio de Janeiro, Brazil. The samples were analyzed using a Diagnostic System Laboratories kit. For data analysis, age- and sex-specific figures were fitted after transformation of IGF-I values. In adulthood, a slow age-dependent decrease was found. There was no significant difference in IGF-I values between men and women. This study established age-specific IGF-I reference values, for a healthy Brazilian adult population, determined by a widely IGF-I, IRMA used currently in Brazil.

  4. The roles of integrins and extracellular matrix proteins in the insulin-like growth factor I-stimulated chemotaxis of human breast cancer cells.

    Science.gov (United States)

    Doerr, M E; Jones, J I

    1996-02-02

    The effects of insulin-like growth factor I (IGF-I) on the migration of two human breast cancer cell lines, MCF-7 and MDA-231, were examined using a modified Boyden chamber. 10 ng/ml was the optimal IGF-I concentration for stimulation of migration. The majority of IGF-I-stimulated migration in both cell types was due to chemotaxis. MCF-7 cells failed to migrate on membranes coated with gelatin or fibronectin and migrated only in small numbers on laminin. In contrast, when vitronectin- or type IV collagen-coated membranes were used, the MCF-7 cells migrated in large numbers specifically in response to IGF-I but not to 10% fetal calf serum, epidermal growth factor, fibroblast growth factor, or platelet derived growth factor-BB. An IGF-I receptor-blocking antibody inhibited IGF-I-stimulated migration in both cell types. In addition, a blocking antibody to the alpha v beta 5 integrin (a vitronectin receptor) inhibited migration of MCF-7 cells in response to IGF-I through vitronectin but not through type IV collagen. Similarly, blocking antibodies specific for alpha 2 and beta 1 integrins significantly inhibited migration of both cell types through type IV collagen-coated membranes but not through vitronectin-coated membranes. We conclude that: 1) IGF-I stimulates migration of these two cell types through the IGF-I receptor; 2) interaction of vitronectin with the alpha v beta 5 integrin or collagen with the alpha 2 beta 1 integrin is necessary for the complete IGF-I response in MCF-7 cells, and 3) because migration represents an in vitro model for metastatic spread, integrins, extracellular matrix proteins, and IGF-I may play coordinated roles in the metastasis of breast cancer in vivo.

  5. The immune-endocrine loop during aging: role of growth hormone and insulin-like growth factor-I.

    Science.gov (United States)

    Burgess, W; Liu, Q; Zhou, J; Tang, Q; Ozawa, A; VanHoy, R; Arkins, S; Dantzer, R; Kelley, K W

    1999-01-01

    Why a primary lymphoid organ such as the thymus involutes during aging remains a fundamental question in immunology. Aging is associated with a decrease in plasma growth hormone (somatotropin) and IGF-I, and this somatopause of aging suggests a connection between the neuroendocrine and immune systems. Several investigators have demonstrated that treatment with either growth hormone or IGF-I restores architecture of the involuted thymus gland by reversing the loss of immature cortical thymocytes and preventing the decline in thymulin synthesis that occurs in old or GH-deficient animals and humans. The proliferation, differentiation and functions of other components of the immune system, including T and B cells, macrophages and neutrophils, also demonstrate age-associated decrements that can be restored by IGF-I. Knowledge of the mechanism by which cytokines and hormones influence hematopoietic cells is critical to improving the health of aged individuals. Our laboratory has recently demonstrated that IGF-I prevents apoptosis in promyeloid cells, which subsequently permits these cells to differentiate into neutrophils. We also demonstrated that IL-4 acts much like IGF-I to promote survival of promyeloid cells and to activate the enzyme phosphatidylinositol 3'-kinase (PI 3-kinase). However, the receptors for IGF-I and IL-4 are completely different, with the intracellular beta chains of the IGF receptor possessing intrinsic tyrosine kinase activity and the alpha and gammac subunit of the heterodimeric IL-4 receptor utilizing the Janus kinase family of nonreceptor protein kinases to tyrosine phosphorylate downstream targets. Both receptors share many of the components of the PI 3-kinase signal transduction pathway, converging at the level of insulin receptor substrate-1 or insulin receptor subtrate-2 (formally known as 4PS, or IL-4 Phosphorylated Substrate). Our investigations with IGF-I and IL-4 suggest that PI 3-kinase inhibits apoptosis by maintaining high levels of

  6. Skeletal unloading causes resistance of osteoprogenitor cells to parathyroid hormone and to insulin-like growth factor-I

    Science.gov (United States)

    Kostenuik, P. J.; Harris, J.; Halloran, B. P.; Turner, R. T.; Morey-Holton, E. R.; Bikle, D. D.

    1999-01-01

    Skeletal unloading decreases bone formation and osteoblast number in vivo and decreases the number and proliferation of bone marrow osteoprogenitor (BMOp) cells in vitro. We tested the ability of parathyroid hormone (PTH) to stimulate BMOp cells in vivo by treating Sprague Dawley rats (n = 32) with intermittent PTH(1-34) (1 h/day at 8 microg/100 g of body weight), or with vehicle via osmotic minipumps during 7 days of normal weight bearing or hind limb unloading. Marrow cells were flushed from the femur and cultured at the same initial density for up to 21 days. PTH treatment of normally loaded rats caused a 2.5-fold increase in the number of BMOp cells, with similar increases in alkaline phosphatase (ALP) activity and mineralization, compared with cultures from vehicle-treated rats. PTH treatment of hind limb unloaded rats failed to stimulate BMOp cell number, ALP activity, or mineralization. Hind limb unloading had no significant effect on PTH receptor mRNA or protein levels in the tibia. Direct in vitro PTH challenge of BMOp cells isolated from normally loaded bone failed to stimulate their proliferation and inhibited their differentiation, suggesting that the in vivo anabolic effect of intermittent PTH on BMOp cells was mediated indirectly by a PTH-induced factor. We hypothesize that this factor is insulin-like growth factor-I (IGF-I), which stimulated the in vitro proliferation and differentiation of BMOp cells isolated from normally loaded bone, but not from unloaded bone. These results suggest that IGF-I mediates the ability of PTH to stimulate BMOp cell proliferation in normally loaded bone, and that BMOp cells in unloaded bone are resistant to the anabolic effect of intermittent PTH therapy due to their resistance to IGF-I.

  7. Recombinant gilthead seabream (Sparus aurata) insulin-like growth factor-I: subcloning, expression in Escherichia coli, purification and characterization.

    Science.gov (United States)

    Fine, M; Amuly, R; Sandowski, Y; Marchant, T A; Chan, S J; Gertler, A; Funkenstein, B

    1997-04-01

    Gilthead seabream (Sparus aurata) insulin-like growth factor-I (gsIGF-I) cDNA coding for the mature protein was cloned in a pGEM-3Z vector, and then transferred into prokaryotic expression vector pET-11a and expressed in Escherichia coli BL21(DE3) cells upon induction with isopropyl thiogalactoside. The expressed protein contained within the inclusion-body pellet was solubilized in 4.5 M urea, refolded for 24 h at pH 11.3 in the presence of catalytic amounts of cysteine and purified to over 98% purity, as a monomeric methionyl-gsIGF-I. Amino acid composition and N-terminal sequence confirmed the identity to be the predicted protein. Binding assays of the 125I-gsIGF-I to gilthead seabream or carp (Cyprinus carpio) sera resulted in high specific binding, indicating the existence of one or more IGF-binding proteins. In binding experiments to crude gilthead seabream brain homogenate, using human (h) IGF-I as a ligand, the respective IC50 value of hIGF-I was about fourfold lower than that of gsIGF-I. Recombinant gsIGF-I exhibited mitogenic activity in a mouse mammary gland-derived MME-L1 cell line which was approximately 200-fold lower than that of hIGF-1. Binding experiments to intact MME-L1 cells suggests that this difference most likely results from a correspondingly lower affinity for IGF-I receptor in these cells. In contrast, the activities of gsIGF-I and hIGF-I measured by 35S uptake by gill arches from the goldfish (Carassius auratus) were identical, indicating that the recombinant gsIGF-I is biologically active.

  8. Interaction of the αβ dimers of the insulin-like growth factor I receptor required for receptor autophosphorylation

    International Nuclear Information System (INIS)

    Tollesfsen, S.E.; Stoszek, R.M.; Thompson, K.

    1991-01-01

    The authors have recently found that association of the two αβ dimers of the insulin-like growth factor I (IGF I) receptor is required for formation of a high-affinity binding site for IGF I. To determine the structural requirements for IGF I activated kinase activity, they have examined the effect of dissociation of the two αβ dimers of the IGF I receptor on β subunit autophosphorylation. The αβ dimers formed after treatment with 2 mM dithiothreitol (DTT) at pH 8.75 for 5 min were separated from IGF I receptor remaining as tetramers after DTT treatment by fast protein liquid chromatography on a Superose 6 gel filtration column. Purification of the αβ dimers was confirmed by Western blot analysis using 125 I-labeled αIR-3, a monoclonal antibody to the IGF I receptor. Autophosphorylation of the IGF I receptor (αβ) 2 tetramer, treated without DTT or remaining after DTT treatment, is stimulated 1.6-2.9-fold by IGF I. In contrast, autophosporylation of the αβ dimers incubated in the presence or absence of IGF I (100 ng/mL) does not occur. Both IGF I receptor dimers and tetramers exhibit similar kinase activities using the synthetic substrate Arg-Arg-Leu-Ile-Glu-Asp-Ala-Glu-Tyr-Ala-Ala-Arg-Gly, indicating that the failure to detect autophosphorylation of the IGF I receptor dimers does not result from inactivation of the kinase by DTT treatment. They conclude that autophosphorylation of the IGF I receptor depends upon the interaction of the two αβ dimers

  9. Effects of green tea polyphenols, insulin-like growth factor I and glucose on developmental competence of bovine oocytes

    Directory of Open Access Journals (Sweden)

    Zhengguang Wang

    2012-12-01

    Full Text Available The present study examined the effects of green tea polyphenols (GTP, insulin-like growth factor-I (IGF-I and glucose on oocyte in vitro maturation, subsequent embryo development and blastocyst quality in bovine. Cumulus-oocyte complexes (COC were aspirated from the ovaries and cultured in synthetic oviduct fluid supplemented with MEM amino acids (SOFaa media supplemented with one of the following supplements: GTP (0, 10, 15 and 20 µM, IGF-I (0, 50, 100 and 150 ng/mL or glucose (0, 1.5, 5.6 and 20 mM for 24 h. The results showed that oocytes cultured in media supplemented with 15 µM GTP, 100 ng/mL IGF-I and 5.6 mM glucose, in separate experiments, have higher cleavage and blastocyst rates compared with oocytes cultured in media without or with other concentration of GTP, IGF-I and glucose. Then these three substances with the concentration above were added together into SOFaa media and constituted a modified medium (Modified SOFaa. The COC were cultured in control SOFaa media and modified SOFaa media, respectively. The results showed that modified SOFaa media increased the intracellular glutathione concentration of matured oocytes, blastocyst rates and total cell numbers and cell numbers of inner cell mass per blastocyst compared with the control. Supplementing of GTP, IGF-I and glucose synchronously to maturation media can increase the intracellular GSH concentration of oocytes after in vitro maturation, and improve the embryo development and blastocyst quality in bovine.

  10. Insulin-like growth factor-I gene therapy reverses morphologic changes and reduces hyperprolactinemia in experimental rat prolactinomas

    Directory of Open Access Journals (Sweden)

    Bracamonte Maria I

    2008-01-01

    Full Text Available Abstract Background The implementation of gene therapy for the treatment of pituitary tumors emerges as a promising complement to surgery and may have distinct advantages over radiotherapy for this type of tumors. Up to now, suicide gene therapy has been the main experimental approach explored to treat experimental pituitary tumors. In the present study we assessed the effectiveness of insulin-like growth factor I (IGF-I gene therapy for the treatment of estrogen-induced prolactinomas in rats. Results Female Sprague Dawley rats were subcutaneously implanted with silastic capsules filled with 17-β estradiol (E2 in order to induce pituitary prolactinomas. Blood samples were taken at regular intervals in order to measure serum prolactin (PRL. As expected, serum PRL increased progressively and 23 days after implanting the E2 capsules (Experimental day 0, circulating PRL had undergone a 3–4 fold increase. On Experimental day 0 part of the E2-implanted animals received a bilateral intrapituitary injection of either an adenoviral vector expressing the gene for rat IGF-I (RAd-IGFI, or a vector (RAd-GFP expressing the gene for green fluorescent protein (GFP. Seven days post vector injection all animals were sacrificed and their pituitaries morphometrically analyzed to evaluate changes in the lactotroph population. RAd-IGFI but not RAd-GFP, induced a significant fall in serum PRL. Furthermore, RAd-IGFI but not RAd-GFP significantly reversed the increase in lactotroph size (CS and volume density (VD induced by E2 treatment. Conclusion We conclude that IGF-I gene therapy constitutes a potentially useful intervention for the treatment of prolactinomas and that bioactive peptide gene delivery may open novel therapeutic avenues for the treatment of pituitary tumors.

  11. Polymorphism of Insulin-like growth factor-I (IGF-I gene and their effect on growth traits in Indonesia native chicken

    Directory of Open Access Journals (Sweden)

    M.A Mu'in

    2009-12-01

    Full Text Available The research was aimed is to detect Insulin-like growth factor-I (IGF-I gene polymorphism and their effect on growth traits in Indonesia natives chicken. Seventy two Indonesian native chicken are going to be used in this research. The polymorphism of IGF-I gene was detected by PCR-RFLP/Pst-I. Four growth traits (body weight at 1, 2, 3, and 4 months were recorded for analyzing the association between IGF-I gene polymorphism and growth performance.The results showed that allele A (621 bp and allele B (364 and 257 bp were found in this research. It was found that Indonesian native chicken carried high frequencies of allele A (0.82, and frequencies of IGF-I genotypes (AA, AB, BB were 68.0, 27.8, and 4,2%, respectively. When compared to the IGF-I genotypes, the BB genotype had the highest body weight at 1, 2, 3, and 4 month (P<0.05. The results showed that the B allele was positive of associated to a higher growth rate. Therefore, these results suggest that there is a possibility of IGF-I genotypes acting as a molecular marker for growth rate of Indonesia native.

  12. Experimental diabetes increases insulin-like growth factor I and II receptor concentration and gene expression in kidney

    International Nuclear Information System (INIS)

    Werner, H.; Shen-Orr, Z.; Stannard, B.; Burguera, B.; Roberts, C.T. Jr.; LeRoith, D.

    1990-01-01

    Insulinlike growth factor I (IGF-I) is a mitogenic hormone with important regulatory roles in growth and development. One of the target organs for IGF-I action is the kidney, which synthesizes abundant IGF-I receptors and IGF-I itself. To study the involvement of IGF-I and the IGF-I receptor in the development of nephropathy, one of the major complications of diabetes mellitus, we measured the expression of these genes in the kidney and in other tissues of the streptozocin-induced diabetic rat. The binding of 125I-labeled IGF-I to crude membranes was measured in the same tissues. We observed a 2.5-fold increase in the steady-state level of IGF-I-receptor mRNA in the diabetic kidney, which was accompanied by a 2.3-fold increase in IGF-I binding. In addition to this increase in IGF-I binding to the IGF-I receptor, there was also binding to a lower-molecular-weight material that may represent an IGF-binding protein. No change was detected in the level of IGF-I-peptide mRNA. Similarly, IGF-II-receptor mRNA levels and IGF-II binding were significantly increased in the diabetic kidney. IGF-I- and IGF-II-receptor mRNA levels and IGF-I and IGF-II binding returned to control values after insulin treatment. Because the IGF-I receptor is able to transduce mitogenic signals on activation of its tyrosine kinase domain, we hypothesize that, among other factors, high levels of receptor in the diabetic kidney may also be involved in the development of diabetic nephropathy. Increased IGF-II-receptor expression in the diabetic kidney may be important for the intracellular transport and packaging of lysosomal enzymes, although a role for this receptor in signal transduction cannot be excluded. Finally, the possible role of IGF-binding proteins requires further study

  13. Effects of insulin-like growth factor-I, insulin, and leucine on protein turnover and pathways that regulate ubiquitin ligase expression in rainbow trout primary myocytes

    Science.gov (United States)

    The effects of insulin-like growth factor-I (IGF-I), insulin, and leucine on protein turnover and pathways that regulate proteolytic gene expression and protein polyubiquitination were investigated in primary cultures of four day old rainbow trout myocytes. Supplementing media with 100 nM IGF-I inc...

  14. Insulin-like growth factor I (IGF-I) replacement therapy increases albumin concentration in liver cirrhosis : Results of a pilot randomized controlled clinical trial

    NARCIS (Netherlands)

    Conchillo, M; de Knegt, RJ; Payeras, M; Quiroga, J; Sangro, B; Herrero, JI; Castilla-Cortazar, [No Value; Frystyk, J; Flyvbjerg, A; Yoshizawa, C; Jansen, PLM; Scharschmidt, B; Prieto, J

    2005-01-01

    Background/Aims: Insulin-like growth factor I (IGF-I) is an anabolic hormone synthesized in the liver whose levels decrease sharply in liver cirrhosis. Methods: We conducted a randomized double-blind placebo-controlled clinical trial to evaluate the effect of subcutaneous administration of IGF-I (20

  15. Relationship between Insulin-Like Growth Factor I Levels, Early Insulin Treatment, and Clinical Outcomes of Very Low Birth Weight Infants

    NARCIS (Netherlands)

    Beardsall, K.; Vanhaesebrouck, S.; Frystyk, J.; Ogilvy-Stuart, A.L.; Vanhole, C.; van Weissenbruch, M.M.; Midgley, P.; Thio, M.; Cornette, L.; Gill, B.; Ossuetta, I.; Iglesias, I.; Theyskens, C.; de Jong, M.; Ahluwalia, J.S.; de Zegher, F.; Dunger, D.B.

    2014-01-01

    Objectives Insulin regulates the secretion of insulin-like growth factor I (IGF-I) in the newborn, and low levels of IGF-I have been linked to neonatal morbidity. As part of the Neonatal Insulin Replacement Therapy in Europe Trial, we investigated the impact of early insulin treatment on IGF-I

  16. NEUROPROTECTIVE EFFICACY OF SUBCUTANEOUS INSULIN-LIKE GROWTH FACTOR-I ADMINISTRATION IN NORMOTENSIVE AND HYPERTENSIVE RATS WITH AN ISCHEMIC STROKE

    NARCIS (Netherlands)

    de Geyter, D.; Stoop, W.; Sarre, S.; de Keyser, J.; Kooijman, R.

    2013-01-01

    The aim of this study was to test the insulin-like growth factor-I (IGF-I) as a neuroprotective agent in a rat model for ischemic stroke and to compare its neuroprotective effects in conscious normotensive and spontaneously hypertensive rats. The effects of subcutaneous IGF-I injection were

  17. Cloning and expression analysis of myostatin, fibroblast growth factor 6, insulin-like growth factor I and II in liver and muscle of sea bass (Dicentrarchus labrax, L. during long-term fasting and refeeding

    Directory of Open Access Journals (Sweden)

    M. Saroglia

    2010-04-01

    Full Text Available The exceptionally fast growth that fish experience after periods of fasting has been called “compensatory growth”. This phenomenon has been studied in intensive aquaculture as a means of enhancing growth rates, but the mechanisms by which food intake activates an increase in somatic growth, and especially in muscle growth, are complex and not yet fully understood. In the present paper, we describe the molecular cloning and sequencing of sea bass (Dicentrarchus labrax myostatin (MSTN and fibroblast growth factor 6 (FGF6, which have been shown to be major genetic determinants of skeletal muscle growth, together with insulin-like growth factor I (IGFI and IGF-II, which are potent mitogens known to play important roles in growth and development. We then report the pattern of expression of the four aforementioned genes, in liver and myotomal muscle in response to prolonged fasting and refeeding. Nutritional status significantly influenced the expression of IGF-I, IGF-II and MSTN, whereas the muscular FGF6 expression levels were not affected by the feeding status of the animals. Taken together these data indicate that IGF-I, IGF-II and MSTN are involved in the sea bass muscle compensatory growth induced by refeeding, whereas FGF6 probably has not a role in this phenomenon.

  18. The neuroprotective effects of intramuscular insulin-like growth factor-I treatment in brain ischemic rats.

    Directory of Open Access Journals (Sweden)

    Heng-Chih Chang

    Full Text Available Brain ischemia leads to muscle inactivity-induced atrophy and may exacerbate motor function deficits. Intramuscular insulin-like growth factor I (IGF-I injection has been shown to alleviate the brain ischemia-induced muscle atrophy and thus improve the motor function. Motor function is normally gauged by the integrity and coordination of the central nervous system and peripheral muscles. Whether brain ischemic regions are adaptively changed by the intramuscular IGF-I injection is not well understood. In this study, the effect of intramuscular IGF-I injection was examined on the central nervous system of brain ischemic rats. Rats were divided into 4 groups: sham control, brain ischemia control, brain ischemia with IGF-I treatment, and brain ischemia with IGF-I plus IGF-I receptor inhibitor treatment. Brain ischemia was induced by right middle cerebral artery occlusion. IGF-I and an IGF-1 receptor inhibitor were injected into the affected calf and anterior tibialis muscles of the treated rats for 4 times. There was an interval of 2 days between each injection. Motor function was examined and measured at the 24 hours and 7 days following a brain ischemia. The affected hind-limb muscles, sciatic nerve, lumbar spinal cord, and motor cortex were collected for examination after euthanizing the rats. IGF-I expression in the central nervous system and affected muscles were significantly decreased after brain ischemia. Intramuscular IGF-I injection increased the IGF-I expression in the affected muscles, sciatic nerve, lumbar spinal cord, and motor cortex. It also increased the p-Akt expression in the affected motor cortex. Furthermore, intramuscular IGF-I injection decreased the neuronal apoptosis and improved the motor function. However, co-administration of the IGF-I receptor inhibitor eliminated these effects. Intramuscular IGF-I injection after brain ischemia attenuated or reversed the decrease of IGF-I in both central and peripheral tissues, and

  19. The growth hormone dependent serine protease inhibitor, Spi 2.1 inhibits the des (1-3) insulin-like growth factor-I generating protease.

    Science.gov (United States)

    Maake, C; Yamamoto, H; Murphy, L J

    1997-12-01

    The conversion of insulin-like growth factor-I (IGF-I) to the biologically more active des (1-3) IGF-I variant is catalyzed by a ubiquitous protease. This proteolytic activity is inhibited by human alpha1-antitrypsin and soy-bean trypsin inhibitor and is up-regulated in serum and tissue extracts of hypophysectomized rats. These observations lead us to investigate whether the growth hormone regulated, serine protease inhibitor, Spi 2.1 was able to inhibit the des (1-3) IGF-I generating protease. Dihydrofolate reductase deficient Chinese hamster ovary (CHO(dhfr-ve)) cells were transfected with a rat Spi 2.1 expression vector containing the dhfr and neomycin resistance gene. Stable transfectants were selected using G418 and amplified using methotrexate. Conditioned medium from Spi 2.1 transfected CHO cells potently inhibited proteolytic activity directed against a synthetic hexa-peptide with a sequence identical to the N-terminal of IGF-I. In contrast conditioned medium from wild-type CHO cells had little effect. Based upon these observations we suggest that our previous finding of enhanced des (1-3) IGF-I generating protease activity in growth hormone deficient rats may be, at least partly explained by reduced levels of Spi 2.1. Furthermore, we propose that the regulation of the generation of des (1-3) IGF-I may be an additional potential site of growth hormone regulation of IGF-I action.

  20. Novel Single Nucleotide Polymorphisms of the Insulin-Like Growth Factor-I Gene and Their Associations with Growth Traits in Common Carp (Cyprinus carpio L.

    Directory of Open Access Journals (Sweden)

    Xiu Feng

    2014-12-01

    Full Text Available Insulin-like growth factor-I (IGF-I plays an important role in the growth and development of vertebrates. To study polymorphisms of IGF-I, we screened a total of 4555 bp of genomic sequences in four exons and partial introns for the discovery of single nucleotide polymorphism (SNP in common carp (Cyprinus carpio. Three SNPs (g.3759T>G, g.7627T>A and g.7722T>C in intron 2 and a nonsynonymous SNP (g.7892C>T in exon 3 were identified in a pilot population including random parents and their progenies. 289 progenies were further genotyped for studying possible associations between genotypes or combined genotypes and growth traits. The results showed that the locus g.7627T>A was significantly associated with body weight and body length, and fish with genotype AA had a mean body weight 5.9% higher than those with genotype TT. No significant associations were observed between genotypes of other loci and growth traits. However, when both g.7627T>A and g.7722T>C were considered, the combined genotype TT/TT was extremely associated with the lowest values of body length and body weight and the highest K value in comparison with other diplotypes (p < 0.01. These results suggest that genotype AA at g.7627T>A and its combined genotypes with alleles from another locus have positive effects on growth traits, which would be a candidate molecular marker for further studies in marker-assisted selection in common carp.

  1. Localization and quantification of binding sites for follicle-stimulating hormone, luteinizing hormone, growth hormone, and insulin-like growth factor I in sheep ovarian follicles.

    Science.gov (United States)

    Eckery, D C; Moeller, C L; Nett, T M; Sawyer, H R

    1997-09-01

    In sheep, growth and development of ovarian follicles beyond 2 mm in diameter is acutely dependent on gonadotropin support. As a consequence, following hypophysectomy (HPX) or hypothalamic-pituitary stalk disconnection (HPD), growth of follicles beyond 2 mm is arrested and all follicles > 2 mm undergo atresia. Although administration of exogenous gonadotropins stimulates follicular growth and ovulation in HPD ewes, follicles in HPX ewes remain unresponsive unless growth hormone (GH) is also given. To determine whether the difference in follicular sensitivity to gonadotropins after HPD (gonadotropin sensitive) or HPX (gonadotropin insensitive) is related to the distribution and quantity of binding sites for FSH, LH, and/or insulin-like growth factor I (IGF-I), binding sites for these hormones were localized and quantified using topical autoradiography in healthy follicles from control (pituitary-intact), HPD, and HPX ewes. In addition, in situ hybridization was performed to localize mRNA for GH and FSH receptors. Irrespective of treatment, binding of FSH and mRNA for FSH receptor were greatest (p membrana granulosa; LH binding was greatest (p receptor was most abundant (p membrana granulosa and oocytes of small antral and preantral follicles. Compared to levels in controls and HPD ewes, the level of GH receptor mRNA was lower (p receptors for FSH, LH, or IGF-I. The observed reduction of mRNA for GH receptor in the membrana granulosa of follicles from HPX ewes provides evidence that GH may play an important role in early stages of folliculogenesis and that it is involved in the maintenance of sensitivity to gonadotropins.

  2. Mecasermin rinfabate: insulin-like growth factor-I/insulin-like growth factor binding protein-3, mecaserimin rinfibate, rhIGF-I/rhIGFBP-3.

    Science.gov (United States)

    2005-01-01

    Insmed is developing mecasermin rinfabate, a recombinant complex of insulin-like growth factor-I (rhIGF-I) and binding protein-3 (rhIGFBP-3) [insulin-like growth factor-I/insulin-like growth factor binding protein-3, rhIGF-I/rhIGFBP-3, SomatoKine], for a number of metabolic and endocrine indications. In the human body, IGF-I circulates in the blood bound to a binding protein-3 (IGFBP-3), which regulates the delivery of IGF-I to target tissues, and particular proteases clip them apart in response to stresses and release IGF-I as needed. IGF-I, a naturally occurring hormone, is necessary for normal growth and metabolism. For the treatment of IGF-I deficiency, it is desirable to administer IGF-I bound to IGFBP-3 to maintain the normal equilibrium of these proteins in the blood. Mecasermin rinfabate (rhIGF-I/rhIGFBP-3) mimics the effects of the natural protein complex in the bloodstream and would augment the natural supply of these linked compounds. The most advanced indication in development of mecasermin rinfabate is the treatment of severe growth disorders due to growth hormone insensitivity syndrome (GHIS), also called Laron syndrome. GHIS is a genetic condition in which patients do not produce adequate quantities of IGF because of a failure to respond to the growth hormone signal. This results in a slower growth rate and short stature. Mecasermin rinfabate also has potential as replacement therapy for IGF-I, which may become depleted in indications such as major surgery, organ damage/failure, traumatic injury, cachexia and severe burn trauma. It also has potential for the treatment of osteoporosis. Mecasermin rinfabate was developed by Celtrix using its proprietary recombinant protein production technology. Subsequently, Celtrix was acquired by Insmed Pharmaceuticals on 1 June 2000. Insmed and Avecia of the UK have signed an agreement for manufacturing mecasermin rinfabate and its components, rhIGF-1 and rhIGFBP-3. CGMP clinical production of mecasermin rinfabate

  3. Sustained low-dose growth hormone therapy optimizes bioactive insulin-like growth factor-I level and may enhance CD4 T-cell number in HIV infection

    DEFF Research Database (Denmark)

    Andersen, Ove; Hansen, Birgitte Rønde; Troensegaard, William

    2010-01-01

    expedient IGF-I levels and improve CD4 T-cell response. Total and free IGF-I increased at week 36 (+97%, P CD4 T-cell number increased at week 36...... (+15%, P cells/microL). Following rhGH dose reduction, total IGF-I and CD4 T-cell number remained increased at week 88 (+44%, P = 0.01 and +33%, P ...High-dose recombinant human growth hormone (rhGH) (2-6 mg/day) regimes may facilitate T-cell restoration in patients infected with human immunodeficiency virus (HIV) on highly active antiretroviral therapy (HAART). However, high-dose rhGH regimens increase insulin-like growth factor-I (IGF...

  4. Neuroprotective efficacy of subcutaneous insulin-like growth factor-I administration in normotensive and hypertensive rats with an ischemic stroke.

    Science.gov (United States)

    De Geyter, D; Stoop, W; Sarre, S; De Keyser, J; Kooijman, R

    2013-10-10

    The aim of this study was to test the insulin-like growth factor-I (IGF-I) as a neuroprotective agent in a rat model for ischemic stroke and to compare its neuroprotective effects in conscious normotensive and spontaneously hypertensive rats. The effects of subcutaneous IGF-I injection were investigated in both rat strains using the endothelin-1 rat model for ischemic stroke. Motor-sensory functions were measured using the Neurological Deficit Score. Infarct size was assessed by Cresyl Violet staining. Subcutaneous administration of IGF-I resulted in significantly reduced infarct volumes and an increase in motor-sensory functions in normotensive rats. In these rats, IGF-I did not modulate blood flow in the striatum and had no effect on the activation of astrocytes as assessed by GFAP staining. In hypertensive rats, the protective effects of IGF-I were smaller and not always significant. Furthermore, IGF-I significantly reduced microglial activation in the cortex of hypertensive rats, but not in normotensive rats. More detailed studies are required to find out whether the reduction by IGF-I of microglial activation contributes to an impairment IGF-I treatment efficacy. Indeed, we have shown before that microglia in hypertensive rats have different properties compared to those in control rats, as they exhibit a reduced responsiveness to ischemic stroke and lipopolysaccharide. Copyright © 2013 IBRO. Published by Elsevier Ltd. All rights reserved.

  5. The ligand specificities of the insulin receptor and the insulin-like growth factor I receptor reside in different regions of a common binding site

    Energy Technology Data Exchange (ETDEWEB)

    Kjeldsen, T.; Andersen, A.S.; Wiberg, F.C.; Rasmussen, J.S.; Schaeffer, L.; Balschmidt, P.; Moller, K.B.; Moller, N.P.H. (Novo Nordisk, Bagsvaerd (Denmark))

    1991-05-15

    To identify the region(s) of the insulin receptor and the insulin-like growth factor I (IGF-I) receptor responsible for ligand specificity (high-affinity binding), expression vectors encoding soluble chimeric insulin/IGF-I receptors were prepared. The chimeric receptors were expressed in mammalian cells and partially purified. Binding studies revealed that a construct comprising an IGF-I receptor in which the 68 N-terminal amino acids of the insulin receptor {alpha}-subunit had replaced the equivalent IGF-I receptor segment displayed a markedly increased affinity for insulin. In contrast, the corresponding IGF-I receptor sequence is not critical for high-affinity IGF-I binding. It is shown that part of the cysteine-rich domain determines IGF-I specificity. The authors have previously shown that exchanging exons 1, 2, and 3 of the insulin receptor with the corresponding IGF-I receptor sequence results in loss of high affinity for insulin and gain of high affinity for IGF-I. Consequently, it is suggested that the ligand specificities of the two receptors (i.e., the sequences that discriminate between insulin and IGF-I) reside in different regions of a binding site with common features present in both receptors.

  6. Predicting growth in angus bulls: the use of GHRH challenge, insulin-like growth factor-I, and insulin-like growth factor binding proteins.

    Science.gov (United States)

    Connor, E E; Barao, S M; Kimrey, A S; Parlier, A B; Douglass, L W; Dahl, G E

    2000-11-01

    Plasma IGF-I, IGF binding protein-2 (IGFBP-2), and IGFBP-3 were quantified in growing Angus bulls (n = 56) to determine their relationship with postweaning growth and carcass ultrasound measurements. In addition, GH response to GHRH challenge (area-under-the-curve GH [AUC-GH) was determined for each bull as part of a previous study. Blood was collected by jugular venipuncture at the start of a 140-d postweaning growth performance test and at 28 d intervals for plasma IGF-I determination by RIA. Plasma IGFBP-2 and -3 content was measured at the start of the study, on d 70, and d 140 by Western ligand blotting. Individual weights and hip heights were measured every 28 d during the study and carcass longissimus muscle area, intramuscular fat percentage, and carcass backfat were estimated by ultrasound on d 140. Greater plasma IGF-I at the start of the performance test was associated with reduced postweaning ADG and increased longissimus area. Throughout the performance test period, the correlations between plasma IGF-I and hip height were consistently positive, ranging from 0.10 to 0.38, but the correlations between ADG and IGF-I varied from -0.32 to 0.31. Age-adjusted d-1 plasma IGFBP-2 was related to ADG during the performance test, explaining nearly 30% of the variation in ADG. A model combining weaning age, IGFBP-2, and AUC-GH showed a strong relationship with ADG (R2 = 0.40). Plasma IGFBP-2 and -3 were not related to carcass characteristics, and IGFBP-3 was not related to growth rates. This study provides additional evidence for the variable relationship between plasma IGF-I and growth rates in cattle. A significant positive relationship between plasma IGFBP-2, AUC-GH, and postweaning ADG warrants further investigation.

  7. New advances in understanding thyroid-associated ophthalmopathy and the potential role for insulin-like growth factor-I receptor [version 1; referees: 2 approved

    OpenAIRE

    Terry J Smith

    2018-01-01

    Thyroid-associated ophthalmopathy (TAO), a localized periocular manifestation of the autoimmune syndrome known as Graves’ disease, remains incompletely understood. Discussions of its pathogenesis are generally focused on the thyrotropin receptor, the proposed role for which is supported by substantial evidence. Considerations of any involvement of the insulin-like growth factor-I receptor (IGF-IR) in the disease are frequently contentious. In this brief, topically focused review, I have attem...

  8. Insulin-like growth factor I is required for the anabolic actions of parathyroid hormone on mouse bone

    Science.gov (United States)

    Bikle, Daniel D.; Sakata, Takeshi; Leary, Colin; Elalieh, Hashem; Ginzinger, David; Rosen, Clifford J.; Beamer, Wesley; Majumdar, Sharmila; Halloran, Bernard P.

    2002-01-01

    Parathyroid hormone (PTH) is a potent anabolic agent for bone, but the mechanism(s) by which it works remains imperfectly understood. Previous studies have indicated that PTH stimulates insulin-like growth factor (IGF) I production, but it remains uncertain whether IGF-I mediates some or all of the skeletal actions of PTH. To address this question, we examined the skeletal response to PTH in IGF-I-deficient (knockout [k/o]) mice. These mice and their normal littermates (NLMs) were given daily injections of PTH (80 microg/kg) or vehicle for 2 weeks after which their tibias were examined for fat-free weight (FFW), bone mineral content, bone structure, and bone formation rate (BFR), and their femurs were assessed for mRNA levels of osteoblast differentiation markers. In wild-type mice, PTH increased FFW, periosteal BFR, and cortical thickness (C.Th) of the proximal tibia while reducing trabecular bone volume (BV); these responses were not seen in the k/o mice. The k/o mice had normal mRNA levels of the PTH receptor and increased mRNA levels of the IGF-I receptor but markedly reduced basal mRNA levels of the osteoblast markers. Surprisingly, these mRNAs in the k/o bones increased several-fold more in response to PTH than the mRNAs in the bones from their wild-type littermates. These results indicate that IGF-I is required for the anabolic actions of PTH on bone formation, but the defect lies distal to the initial response of the osteoblast to PTH.

  9. Characterization of insulin-like growth factor I and insulin receptors on cultured bovine adrenal fasciculata cells. Role of these peptides on adrenal cell function

    International Nuclear Information System (INIS)

    Penhoat, A.; Chatelain, P.G.; Jaillard, C.; Saez, J.M.

    1988-01-01

    We have characterized insulin-like growth factor I (IGF-I) and insulin receptors in cultured bovine adrenal cells by binding and cross-linking affinity experiments. At equilibrium the dissociation constant and the number of binding sites per cell for IGF-I were 1.4 +/- (SE) 0.3 x 10(-9) M and 19,200 +/- 2,100, respectively. Under reduction conditions, disuccinimidyl suberate cross-linked [ 125 I]iodo-IGF-I to one receptor complex with an Mr of 125,000. Adrenal cells also contain specific insulin receptors with an apparent dissociation constant (Kd) of 10(-9) M. Under reduction conditions [ 125 I]iodo-insulin binds to one band with an approximate Mr of 125,000. IGF-I and insulin at micromolar concentrations, but not at nanomolar concentrations, slightly stimulated DNA synthesis, but markedly potentiated the mitogenic action of fibroblast growth factor. Adrenal cells cultured in a serum-free medium containing transferrin, ascorbic acid, and insulin (5 micrograms/ml) maintained fairly constant angiotensin-II (A-II) receptor concentration per cell and increased cAMP release on response to ACTH and their steroidogenic response to both ACTH and A-II. When the cells were cultured in the same medium without insulin, the number of A-II receptors significantly decreased to 65% and the increased responsiveness was blunted. Treatment of such cells for 3 days with increasing concentrations of IGF-I (1-100 ng/ml) produced a 2- to 3-fold increase in A-II receptors and enhanced the cAMP response (3- to 4-fold) to ACTH and the steroidogenic response (4- to 6-fold) to ACTH and A-II. These effects were time and dose dependent (ED50 approximately equal to 10(-9) M). Insulin at micromolar concentrations produced an effect similar to that of IGF-I, but at nanomolar concentrations the effect was far less

  10. Insulin-like growth factor-I feedback regulation of growth hormone and luteinizing hormone secretion in the pig: evidence for a pituitary site of action.

    Science.gov (United States)

    Barb, C R; Hausman, G J

    2009-06-01

    Three experiments (EXP) were conducted to determine the role of insulin-like growth factor-I (IGF-I) in the control of growth hormone (GH) and LH secretion. In EXP I, prepuberal gilts, 65 ± 6 kg body weight and 140 days of age received intracerebroventricular (ICV) injections of saline (n = 4), 25 μg (n = 4) or 75 μg (n = 4) IGF-I and jugular blood samples were collected. In EXP II, anterior pituitary cells in culture collected from 150-day-old prepuberal gilts (n = 6) were challenged with 0.1, 10 or 1000 nM [Ala15]-h growth hormone-releasing hormone-(1-29)NH2 (GHRH), or 0.01, 0.1, 1, 10, 30 nM IGF-I individually or in combinations with 1000 nM GHRH. Secreted GH was measured at 4 and 24 h after treatment. In EXP III, anterior pituitary cells in culture collected from 150-day-old barrows (n = 5) were challenged with 10, 100 or 1000 nM gonadotropin-releasing hormone (GnRH) or 0.01, 0.1, 1, 10, 30 nM IGF-I individually or in combinations with 100 nM GnRH. Secreted LH was measured at 4 h after treatment. In EXP I, serum GH and LH concentrations were unaffected by ICV IGF-I treatment. In EXP II, relative to control all doses of GHRH increased (P 0.1). In conclusion, under these experimental conditions the results suggest that the pituitary is the putative site for IGF-I modulation of GH and LH secretion. Further examination of the role of IGF-I on GH and LH secretion is needed to understand the inhibitory and stimulatory action of IGF-I on GH and LH secretion.

  11. Changes in calcitropic hormones, bone markers and insulin-like growth factor I (IGF-I) during pregnancy and postpartum

    DEFF Research Database (Denmark)

    Møller, U K; Streym, S; Mosekilde, L

    2013-01-01

    and 36 weeks postpartum. The controls were followed in parallel. RESULTS: P-estradiol (E2), prolactin and 1,25-dihydroxyvitamin D (1,25(OH)2D) increased (pgrowth factor I (IGF......UNLABELLED: Pregnancy and lactation cause major changes in calcium homeostasis and bone metabolism. This population-based cohort study presents the physiological changes in biochemical indices of calcium homeostasis and bone metabolism during pregnancy and lactation INTRODUCTION: We describe...... physiological changes in calcium homeostasis, calcitropic hormones and bone metabolism during pregnancy and lactation. METHODS: We studied 153 women planning pregnancy (n=92 conceived) and 52 non-pregnant, age-matched female controls. Samples were collected prior to pregnancy, once each trimester and 2, 16...

  12. Chronic alcohol consumption, type 2 diabetes mellitus, insulin-like growth factor-I (IGF-I), and growth hormone (GH) in ethanol-treated diabetic rats.

    Science.gov (United States)

    Kim, Soo-Jeong; Ju, Anes; Lim, Seul-Gi; Kim, Dai-Jin

    2013-11-13

    Alcohol has deleterious influences on glucose metabolism which may contribute to the development of type 2 diabetes mellitus (T2DM). Insulin-like growth factor I (IGF-I) and growth hormone (GH), which interact with insulin to modulate metabolic control, have been shown to be related to impaired glucose tolerance. This study was conducted to assess the possibility that altered circulating IGF-I and GH levels contribute to the exacerbation of T2DM by alcohol use in type 2 diabetic Otsuka Long-Evans Tokushima Fatty (OLETF) rats and non-diabetic Long-Evans Tokushima Otsuka (LETO) rats. OLETF rats were pair-fed a Lieber-DeCarli Regular Ethanol diet and LETO rats were pair-fed a control diet for 6 weeks. At 6 weeks, an Intraperitoneal Glucose Tolerance Test (IP-GTT) was performed and IGF-I and GH levels were evaluated. Prior to an IP-GTT, OLETF-Ethanol (O-E) group had significantly a decrease in the mean glucose levels compared to OLETF-Control (O-C) group. At 120 min post IP-GTT, the O-E group had significantly an increase in the mean glucose levels compared to O-C group. The serum IGF-I levels were significantly lower and the serum GH levels were significantly higher in the O-E group than in L-C group. These results suggest that IGF-I and GH are prominent in defining the risk and development of T2DM, and may be adversely affected by heavy alcohol use, possibly mediating its diabetogenic effects. Thus, the overall glucose intolerance in the setting of alcoholism may be attributable to inappropriate alteration of IGF-I and GH levels. © 2013. Published by Elsevier Inc. All rights reserved.

  13. Somatomedin-C/insulin-like growth factor-I and Insulin-like growth factor-II mRNAs in rate fetal and adult tissues

    International Nuclear Information System (INIS)

    Lund, P.K.; Moats-Staats, B.M.; Hynes, M.A.; Simmons, J.G.; Jansen, M.; D'ercole, A.J.; Van Wyk, J.J.

    1986-01-01

    Somatomedin-C or insulin-like growth factor I (Sm-C/IGF-I) and insulin-like growth factor II (IGF-II) have been implicated in the regulation of fetal growth and development. In the present study 32 P-labeled complementary DNA probes encoding human and mouse Sm-C/IGF-I and human IGF-II were used in Northern blot hybridizations to analyze rat Sm-C/IGF-I and IGF-II mRNAs in poly(A + ) RNAs from intestine, liver, lung, and brain of adult rats and fetal rats between day 14 and 17 of gestation. In fetal rats, all four tissues contained a major mRNA of 1.7 kilobase (kb) that hybridized with the human Sm-C/IGF-I cDNA and mRNAs of 7.5, 4.7, 1.7, and 1.2 kb that hybridized with the mouse Sm-C/IGF-I cDNA. Adult rat intestine, liver, and lung also contained these mRNAs but Sm-C/IGF-I mRNAs were not detected in adult rat brain. These findings provide direct support for prior observations that multiple tissues in the fetus synthesize immunoreactive Sm-C/IGF-I and imply a role for Sm-C/IGF-I in fetal development as well as postnatally. Multiple IGF-II mRNAs of estimated sizes 4.7, 3.9, 2.2, 1.75, and 1.2 kb were observed in fetal rat intestine, liver, lung, and brain. The 4.7- and 3.9-kb mRNAs were the major hybridizing IGF-II mRNAs in all fetal tissues. Higher abundance of IGF-II mRNAs in rat fetal tissues compared with adult tissues supports prior hypotheses, based on serum IGF-II concentrations, that IGF-II is predominantly a fetal somatomedin. IGF-II mRNAs are present, however, in some poly(A + ) RNAs from adult rat tissues. The brain was the only tissue in the adult rat where the 4.7- and 3.9-kb IGF-II mRNAs were consistently detected. These findings suggest that a role for IGF-II in the adult rat, particularly in the central nervous system, cannot be excluded

  14. Impact of nutrients on insulin-like growth factor-I, insulin-like growth factor binding protein-3 and their ratio in African American and white males.

    Science.gov (United States)

    McGreevy, Katharine M; Hoel, Brian D; Lipsitz, Stuart R; Hoel, David G

    2007-01-01

    Higher levels of insulin-like growth factor-I (IGF-I) and lower levels of IGF binding protein-3 (IGFBP-3) have been associated with an increased risk of prostate cancer. Nutrition is known to partially regulate IGF levels and it is possible that nutritional factors mediate the impact of IGF levels on prostate cancer risk. A cross-sectional analysis of the impact of nutritional factors measured by a dietary questionnaire on plasma levels of IGF-I, IGFBP-3 and their molar ratio. Multiple linear regression analysis was used to test for effects of nutrients on IGF levels. Prostate cancer screening at the Hollings Cancer Center in Charleston, South Carolina. Ninety-five African American and 138 white males aged 33-83 years attending the screening. In whites, intakes of total, saturated and monounsaturated fats were positively associated with an increase in the molar ratio, while there was no association in African Americans. In African Americans, we found that increasing intake of calcium and dairy servings was positively associated with IGF-I levels. Increased vegetable intake was positively associated with IGFBP-3 in African Americans, while there was no effect in whites. A higher percentage of alcohol in the total diet was significantly associated with a decrease in the molar ratio and an increase in IGFBP-3 in both groups. Our results confirm previous findings of nutritional determinants of IGF levels. Additionally, we found the impact of several nutrients on IGF levels to be different in whites and African Americans, which warrants further investigation.

  15. Insulin-like growth factor I treatment reduces demyelination and up-regulates gene expression of myelin-related proteins in experimental autoimmune encephalomyelitis.

    OpenAIRE

    Yao, D L; Liu, X; Hudson, L D; Webster, H D

    1995-01-01

    To compare effects of insulin-like growth factor I (IGF-I) and placebo treatment on lesions that resemble those seen during active demyelination in multiple sclerosis, we induced experimental autoimmune encephalomyelitis in Lewis rats with an emulsion containing guinea pig spinal cord and Freund's adjuvant. On day 12-13, pairs of rats with the same degree of weakness were given either IGF-I or placebo intravenously twice daily for 8 days. After 8 days of placebo or IGF-I (200 micrograms/day o...

  16. The Supportive Role of Insulin-Like Growth Factor-I in the Differentiation of Murine Mesenchymal Stem Cells into Corneal-Like Cells

    Czech Academy of Sciences Publication Activity Database

    Trošan, Peter; Javorková, Eliška; Zajícová, Alena; Hájková, Michaela; Heřmánková, Barbora; Kössl, Jan; Holáň, Vladimír

    2016-01-01

    Roč. 7, č. 17 (2016), s. 23156-23169 ISSN 1547-3287 R&D Projects: GA ČR(CZ) GA14-12580S; GA MŠk(CZ) ED1.1.00/02.0109; GA MŠk(CZ) LO1309; GA MŠk(CZ) LO1508 Institutional support: RVO:68378041 Keywords : mesenchymal stem cells * corneal-like cells * insulin -like growth factor-I * differentiation Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.562, year: 2016

  17. Serum insulin-like growth factor I (IGF-I) and IGF-binding protein 3 levels are increased in central precocious puberty

    DEFF Research Database (Denmark)

    Juul, A; Scheike, Thomas Harder; Nielsen, C T

    1995-01-01

    between IGF-I and IGFBP-3 (i.e. free biologically active IGF-I) declined concomitantly with a decrease in growth velocity. Serum levels of IGF-I and IGFBP-3 (expressed as the SD score for bone age), but not those of estradiol, correlated with height velocity before and during treatment (r = 0.34; P ...Central precocious puberty (CPP) is characterized by early activation of the pituitary-gonadal axis, which leads to increased growth velocity and development of secondary sexual characteristics. It is generally believed that gonadal sex steroids stimulate pulsatile GH secretion, which, in turn......, stimulates insulin-like growth factor I (IGF-I) and IGF-binding protein 3 (IGFBP-3) production. However, little is known about GH, IGF-I, and IGFBP-3 serum levels in children with precocious puberty. Treatment of CPP by GnRH agonists has become the treatment of choice. However, the effect of long term...

  18. Nonparallel changes of growth hormone (GH) and insulin-like growth factor-I, insulin-like growth factor binding protein-3, and GH-binding protein, after craniospinal irradiation and chemotherapy

    International Nuclear Information System (INIS)

    Nivot, S.; Adan, L.; Souberbielle, J.; Rappaport, R.; Brauner, R.; Benelli, C.; Clot, J.P.; Saucet, C.; Zucker, J.M.

    1994-01-01

    The authors studied the GH-insulin-like growth factor-I (IGF-I) axis serially over 24-36 months in six patients with medulloblastoma who underwent surgical removal of the tumor followed by craniospinal irradiation therapy for 6 weeks and then chemotherapy for 42 weeks. Eighteen and 24 months after beginning irradiation there was a decline in the peak GH secretory response to acute stimulation with arginine/insulin hypoglycemia. Six months after irradiation and during chemotherapy there was a transient decline in IGF-I, IGF binding protein-3 (IGFBP-3), and GH-BP values (respective mean values of 56.1 ± 9.0 ng/mL, 1.1 ± 0.2 μg/mL, and 7.6 ± 3.3% of radioactivity as compared to time 0 values: 139 ± 15 ng/mL, 2.2 ± 0.2 μg/mL, and 20.0 ± 4.0%, P < 0.001), although provoked GH secretion was normal at this time. The IGF-I, IGFBP-3, and GH-BP returned to pretreatment ranges by 12-36 months after initiation of the study. There was also a decline in body mass index and serum protein values at 6 months after irradiation in ligand and immunoblot analysis there was a decline in IGFBP-3 and an abnormal electrophoretic mobility of IGFBP-2 that were both normalized at 36 months. In one patient they observed a high level of IGFBP-3 proteolysis at this time. This study demonstrates that before the decrease of GH secretion in patients receiving cranial irradiation there is a transient phase of GH insensitivity that may be characteristic of the acute therapeutic phase including the chemotherapy. This partial insensitivity may explain the early growth retardation observed in these patients. 28 refs., 4 figs., 1 tab

  19. CCAAT/enhancer-binding protein delta activates insulin-like growth factor-I gene transcription in osteoblasts. Identification of a novel cyclic AMP signaling pathway in bone

    Science.gov (United States)

    Umayahara, Y.; Ji, C.; Centrella, M.; Rotwein, P.; McCarthy, T. L.

    1997-01-01

    Insulin-like growth factor-I (IGF-I) plays a key role in skeletal growth by stimulating bone cell replication and differentiation. We previously showed that prostaglandin E2 (PGE2) and other cAMP-activating agents enhanced IGF-I gene transcription in cultured primary rat osteoblasts through promoter 1, the major IGF-I promoter, and identified a short segment of the promoter, termed HS3D, that was essential for hormonal regulation of IGF-I gene expression. We now demonstrate that CCAAT/enhancer-binding protein (C/EBP) delta is a major component of a PGE2-stimulated DNA-protein complex involving HS3D and find that C/EBPdelta transactivates IGF-I promoter 1 through this site. Competition gel shift studies first indicated that a core C/EBP half-site (GCAAT) was required for binding of a labeled HS3D oligomer to osteoblast nuclear proteins. Southwestern blotting and UV-cross-linking studies showed that the HS3D probe recognized a approximately 35-kDa nuclear protein, and antibody supershift assays indicated that C/EBPdelta comprised most of the PGE2-activated gel-shifted complex. C/EBPdelta was detected by Western immunoblotting in osteoblast nuclear extracts after treatment of cells with PGE2. An HS3D oligonucleotide competed effectively with a high affinity C/EBP site from the rat albumin gene for binding to osteoblast nuclear proteins. Co-transfection of osteoblast cell cultures with a C/EBPdelta expression plasmid enhanced basal and PGE2-activated IGF-I promoter 1-luciferase activity but did not stimulate a reporter gene lacking an HS3D site. By contrast, an expression plasmid for the related protein, C/EBPbeta, did not alter basal IGF-I gene activity but did increase the response to PGE2. In osteoblasts and in COS-7 cells, C/EBPdelta, but not C/EBPbeta, transactivated a reporter gene containing four tandem copies of HS3D fused to a minimal promoter; neither transcription factor stimulated a gene with four copies of an HS3D mutant that was unable to bind osteoblast

  20. A comparative study of age-related hearing loss in wild type and insulin-like growth factor I deficient mice

    Directory of Open Access Journals (Sweden)

    Raquel Riquelme

    2010-06-01

    Full Text Available Insulin-like growth factor-I (IGF-I belongs to the family of insulin-related peptides that fulfils a key role during the late development of the nervous system. Human IGF1 mutations cause profound deafness, poor growth and mental retardation. Accordingly, Igf1−/− null mice are dwarfs that have low survival rates, cochlear alterations and severe sensorineural deafness. Presbycusis (age-related hearing loss is a common disorder associated with aging that causes social and cognitive problems. Aging is also associated with a decrease in circulating IGF-I levels and this reduction has been related to cognitive and brain alterations, although there is no information as yet regarding the relationship between presbycusis and IGF-I biodisponibility. Here we present a longitudinal study of wild type Igf1+/+ and null Igf1−/− mice from 2 to 12 months of age comparing the temporal progression of several parameters: hearing, brain morphology, cochlear cytoarchitecture, insulin-related factors and IGF gene expression and IGF-I serum levels. Complementary invasive and non-invasive techniques were used, including auditory brainstem-evoked response (ABR recordings and in vivo MRI brain imaging. Igf1−/− null mice presented profound deafness at all the ages studied, without any obvious worsening of hearing parameters with aging. Igf1+/+ wild type mice suffered significant age-related hearing loss, their auditory thresholds and peak I latencies augmenting as they aged, in parallel with a decrease in the circulating levels of IGF-I. Accordingly, there was an age-related spiral ganglion degeneration in wild type mice that was not evident in the Igf1 null mice. However, the Igf1−/− null mice in turn developed a prematurely aged stria vascularis reminiscent of the diabetic strial phenotype. Our data indicate that IGF-I is required for the correct development and maintenance of hearing, supporting the idea that IGF-I-based therapies could contribute to

  1. Respons Insulin Like Growth Factor-I Pascalatihan Fisik Sebagai Indikator Peningkatan Densitas Tulang pada Wanita Lanjut Usia

    Directory of Open Access Journals (Sweden)

    Neng Tine Kartinah Almuktabar

    2010-06-01

    Full Text Available Physical exercise is an effort for preventing osteoporosis in the elderly women. However, some indicators for effective, efficient, and safe physical exercises for increasing bone density in the elderly women in Indonesia are still questioning. The main purpose of research was to identify the response's correlation of IGF-I post-exercise progressive resistance exercise (PRE and osteoporosis prevention exercise (SPO on bone density. The experiment with pre-test and post-test design has been done for 16 weeks on April-July 2005. The subjects of this research were 18 elderly women in Ciwaruga Health Community Center (Puskesmas that met some inclusion criteria (55-65 years old, health, and do not consume medicines which have bad effects to bone density. The multiple regression test used as statistical analysis to identify the correlation of acute and chronic responses of IGF-I on bone density. The multiple regression analysis of acute and chronic responses of IGF-1 on bone density on PRE and SPO group showed a deflection point of bone density as much as 0.88 and 0.83g/cm2 (p= 0.000. The regression model of bone density on PRE group=0.239 - 0.0005 acute response + 0.00006 chronic response (p< 0.05. The regression model on SPO:Bone density= 0.158 - 0.0002 acute response + 0.00009 chronic response (p< 0.05. Conclusion: the safe indicator for initial bone density before doing PRE and SPO exercises are 0.88 g/cm2 and 0.83 g/cm2 respectively. Therefore, PRE is relatively more effective and efficient than SPO because PRE has high exercise intensity that can increase bone density in short duration than SPO.

  2. Differential changes in free and total insulin-like growth factor I after major, elective abdominal surgery

    DEFF Research Database (Denmark)

    Skjærbæk, Christian; Frystyk, Jan; Ørskov, Hans

    1998-01-01

    Major surgery is accompanied by extensive proteolysis of insulin-like growth factor (IGF)-binding protein-3 (IGFBP-3). Proteolysis of IGFBP-3 is generally believed to increase IGF bioavailability due to a diminished affinity of the IGFBP-3 fragments for IGFs. We have investigated 18 patients...... undergoing elective ileo-anal J-pouch surgery. Patients were randomized to treatment with GH (12 IU/day; n = 9) or placebo (n = 9) from 2 days before to 7 days after operation. Free IGF-I and IGF-II were measured by ultrafiltration of serum, and IGFBP-3 proteolytic activity was determined by a [125I...

  3. Association of thyroid gland volume, serum insulin-like growth factor-I, and anthropometric variables in euthyroid prepubertal children

    DEFF Research Database (Denmark)

    Boas, M.; Hegedus, L.; Feldt-Rasmussen, U.

    2009-01-01

    CONTEXT AND OBJECTIVE: Few studies have focused on the interrelation between thyroid size, anthropometric variables, and IGF-I in adults, but such data are lacking for children. We have investigated thyroid gland volume and several hormonal and anthropometric variables in prepubertal children....... DESIGN AND PARTICIPANTS: A total of 859 prepubertal euthyroid Danish children aged 4-9 yr underwent a thorough clinical investigation, including anthropometrical measurements and determination of TSH, thyroid hormones, autoantibodies, urinary iodine excretion, and thyroid volume (TV) by ultrasound....... Longitudinal growth data from birth were available. RESULTS: TV increased significantly with age (r = 0.487; P

  4. Prospective study of insulin-like growth factor-I, insulin-like growth factor-binding protein 3, genetic variants in the IGF1 and IGFBP3 genes and risk of coronary artery disease

    NARCIS (Netherlands)

    Ricketts, Sally L.; Rensing, Katrijn L.; Holly, Jeff M.; Chen, Li; Young, Elizabeth H.; Luben, Robert; Ashford, Sofie; Song, Kijoung; Yuan, Xin; Dehghan, Abbas; Wright, Benjamin J.; Waterworth, Dawn M.; Mooser, Vincent; Waeber, Gérard; Vollenweider, Peter; Epstein, Stephen E.; Burnett, Mary S.; Devaney, Joseph M.; Hakonarson, Hakon H.; Rader, Daniel J.; Reilly, Muredach P.; Danesh, John; Thompson, Simon G.; Dunning, Alison M.; van Duijn, Cornelia M.; Samani, Nilesh J.; McPherson, Ruth; Wareham, Nicholas J.; Khaw, Kay-Tee; Boekholdt, S. Matthijs; Sandhu, Manjinder S.

    2011-01-01

    Although experimental studies have suggested that insulin-like growth factor I (IGF-I) and its binding protein IGFBP-3 might have a role in the aetiology of coronary artery disease (CAD), the relevance of circulating IGFs and their binding proteins in the development of CAD in human populations is

  5. The insulin-like growth factors I and II stimulate proliferation of different types of Schwann cells

    DEFF Research Database (Denmark)

    Sondell, M; Svenningsen, Åsa Fex; Kanje, M

    1997-01-01

    A combination of immunocytochemistry for glial specific antigens and bromodeoxyuridine (BrdU) and teasing was used to identify proliferating cells in cultured rat sciatic nerve segments. The nerve segments were exposed to insulin, or the insulin-like growth factors IGF-I and IGF-II. Teasing...... in combination with BrdU immunocytochemistry showed that around 93% of the proliferating cells in the nerve segments were Schwann cells. Immunostaining for BrdU and GFAP (glial fibrillary acid protein) showed that IGF-II enhanced proliferation of Schwann cells surrounding unmyelinated nerve fibres. In contrast......, truncated IGF-I promoted proliferation of Schwann cells of myelinated nerve fibres while insulin increased proliferation of both cell types....

  6. Absorption of milk-borne insulin-like growth factor-I into portal blood of suckling rats.

    Science.gov (United States)

    Philipps, A F; Dvorák, B; Kling, P J; Grille, J G; Koldovský, O

    2000-08-01

    Insulin-like growth factors (IGFs) are potent mitogens that have been implicated in control of growth and development during the perinatal period. These hormones are also present in biologically significant quantities in mammalian milks. Although one site of action of these IGFs may be at the intestinal level, current information about whether they pass intact into the circulation is conflicting. To test the hypothesis that milk-borne IGFs are absorbed into blood in receptor-active form, suckling rats were given either recombinant human (rh)125I-IGF-I or -II (4 x 10(6) counts per minute [cpm]), and the activity present in portal and cardiac blood was examined at 5, 10, 20, and 30 minutes after ingestion for presence of appropriate molecular weight peptides in these samples. In selected samples, purified radioactive samples were tested for their ability to bind competitively to crude membranes bearing IGF receptors. The results of these studies indicate that rh125I-IGF-I is absorbed in receptor-active form into the portal circulation and that maximal amounts are present 20 to 30 minutes after ingestion. Estimation of the presence of intact hormone was made on the basis of the elution profile of samples when run on gel chromatography as well as reversed-phase high-performance liquid chromatography. Isolated samples from portal blood also bound competitively to placental membranes bearing IGF receptors. In contrast, rh125I-IGF-II could not be demonstrated in receptor-active form in portal blood. Chromatography showed appropriate sized peaks with greater activity in portal than cardiac samples, but competitive binding was not appreciated. It is likely that at least milk-borne IGF-I is absorbed intact and may exert effects on liver and other peripheral tissues. In addition, this study lends further credence to the possibility of an enterohepatic circulation for IGF-I.

  7. Associations between plasma insulin-like growth factor-I and the markers of inflammation interleukin 6, C-reactive protein and YKL-40 in an elderly background population

    DEFF Research Database (Denmark)

    Andreassen, Mikkel; Raymond, Ilan; Hildebrandt, Per

    2010-01-01

    The objective of the present study was to test the hypothesis that circulating levels of insulin-like growth factor-I (IGF-I) are inversely associated with inflammatory processes in an elderly background population....

  8. Insulin-like growth factor-I as a possible hormonal mediator of nutritional regulation of reproduction in cattle.

    Science.gov (United States)

    Zulu, Victor Chisha; Nakao, Toshihiko; Sawamukai, Yutaka

    2002-08-01

    The current review aims to establish insulin-like growth factor-1 (IGF-I) as the factor that signals nutritional status to the reproductive axis, and show that assessment of IGF-I in blood early postpartum during the negative energy balance (NEB) period could be used to predict both nutritional and reproductive status in dairy cattle. The review also explores the effect of nutritional status on circulating IGF-I concentrations and the endocrine role of IGF-I on the reproductive axis. IGF-I plays an important role in gonadotropin-induced folliculogenesis, ovarian steroidogenesis and corpus luteum (CL) function. It also modulates pituitary and hypothalamus function. IGF-I clearly has an endocrine role on the reproductive axis. Severe under nutrition significantly reduces plasma IGF-I concentrations. During the critical period of NEB in high yielding dairy cattle early postpartum, IGF-I concentrations are low in blood and its levels are positively correlated to energy status and reproductive function during this period. Changes in circulating IGF-I immediately postpartum may help predict both nutritional and reproductive status in dairy cattle. IGF-I is therefore one of the long sought factors that signal nutritional status to the reproductive axis.

  9. Cultured fibroblast monolayers secrete a protein that alters the cellular binding of somatomedin-C/insulinlike growth factor I

    International Nuclear Information System (INIS)

    Clemmons, D.R.; Elgin, R.G.; Han, V.K.; Casella, S.J.; D'Ercole, A.J.; Van Wyk, J.J.

    1986-01-01

    We studied somatomedin-C/insulinlike growth factor (Sm-C/IGF-I) binding to human fibroblasts in both adherent monolayers and in suspension cultures. The addition of Sm-C/IGF-I in concentrations between 0.5 and 10 ng/ml to monolayers cultures resulted in a paradoxical increase in 125 I-Sm-C/IGF-I binding and concentrations between 25 and 300 ng/ml were required to displace the labeled peptide. The addition of unlabeled insulin resulted in no displacement of labeled Sm-C/IGF-I from the adherent cells. When fibroblast suspensions were used Sm-C/IGF-I concentrations between 1 and 10 ng/ml caused displacement, the paradoxical increase in 125 I-Sm-C/IGF-I binding was not detected, and insulin displaced 60% of the labeled peptide. Affinity cross-linking to fibroblast monolayers revealed a 43,000-mol wt 125 I-Sm-C-binding-protein complex that was not detected after cross-linking to suspended cells. The 43,000-mol wt complex was not detected after cross-linking to smooth muscle cell monolayers, and binding studies showed that 125 I-Sm-C/IGF-I was displaced greater than 90% by Sm-C/IGF-I using concentrations between 0.5 and 10 ng/ml. Because fibroblast-conditioned medium contains the 43,000-mol wt complex, smooth muscle cells were incubated with conditioned medium for 24 h prior to initiation of the binding studies. 125 I-Sm-C/IGF-I-binding increased 1.6-fold compared to control cultures and after cross-linking the 43,000-mol wt complex could be detected on the smooth muscle cell surface. Human fibroblast monolayers secrete a protein that binds 125 I-Sm-C/IGF-I which can be transferred to the smooth muscle cell surface and alters 125I-Sm-C/IGF-I binding

  10. Alleviation of body weight loss by dietary methionine is independent of insulin-like growth factor-I in protein-starved young chickens.

    Science.gov (United States)

    Nagao, Kenji; Oki, Mai; Tsukada, Akira; Kita, Kazumi

    2011-08-01

    It is well known that in protein-starved chickens, small amounts of amino acid supplement, especially methionine, reduces nitrogen excretion and thereby improves nitrogen balance. On the other hand, excess intake of methionine causes growth depression and the growth-depressive effect of excess methionine can be alleviated by consumption of dietary glycine. Insulin-like growth factor-I (IGF-I) is one of various growth-promoting factors relating to the efficiency of animal production and is known to be very sensitive to changes in nutritional status. In the present study, the interactive effect of glycine on nitrogen sparing effect of methionine in protein-starved chickens was examined. In addition, the relation of IGF-I and its specific binding protein to the nitrogen sparing effect of supplemented methionine was also investigated. Two-days refeeding of methionine supplemented to protein-free diet could promptly alleviate body weight loss in protein-starved chickens, and the alleviation of body weight loss by methionine was not improved by glycine supplements. Moreover, such acute alleviation of body weight loss by dietary methionine was independent of the change in plasma IGF-I concentration. 2011 The Authors. Animal Science Journal © 2011 Japanese Society of Animal Science.

  11. Prognostic value of insulinlike growth factor I and its binding protein in patients with alcohol-induced liver disease. EMALD group

    DEFF Research Database (Denmark)

    Møller, Søren; Becker, Povl Ulrik; Juul, A

    1996-01-01

    , and immunoglobulin (Ig) M. When IGF-I or IGFBP-3 were added into this model, a Cox regression analysis showed that either had a significant independent prognostic value. Because IGF-I and IGFBP-3 were closely correlated, they contained almost the same prognostic information. Inclusion of IGF-I gave these results......Insulinlike growth factor I (IGF-I) is a single-polypeptide chain with important anabolic and endocrine activities. The liver is the major source of IGF-I and its binding protein, IGFBP-3. Circulating concentrations of IGF-I and IGFBP-3 are decreased in patients with chronic liver disease...... and correlate with the severity. The aim of this study was to assess the additional prognostic value of IGF-I and IGFBP-3 in patients entered in a large multicenter study (EMALD). Three hundred thirty-seven patients with alcohol-induced liver disease were studied in a randomized placebo-controlled trial...

  12. Serum insulin-like growth factor I (IGF-I) and IGF-binding protein 3 levels are increased in central precocious puberty

    DEFF Research Database (Denmark)

    Juul, A; Scheike, Thomas Harder; Nielsen, C T

    1995-01-01

    , stimulates insulin-like growth factor I (IGF-I) and IGF-binding protein 3 (IGFBP-3) production. However, little is known about GH, IGF-I, and IGFBP-3 serum levels in children with precocious puberty. Treatment of CPP by GnRH agonists has become the treatment of choice. However, the effect of long term...... treatment with GnRH in combination with an antiandrogen (cyproterone acetate) to block the possible effect of adrenal androgens has not previously been evaluated. We, therefore, studied 40 patients with idiopathic CPP that were treated for 24 months with either GnRH analog (Buserelin) in combination...... with cyproterone acetate (Androcur; n = 23) or with long acting GnRH analog (Decapeptyl Depot; n = 17). We found that serum IGF-I levels were increased before treatment in both groups (mean +/- SE, 446 +/- 35 and 391 +/- 35 micrograms/L; P

  13. Changes in calcitropic hormones, bone markers and insulin-like growth factor I (IGF-I) during pregnancy and postpartum: a controlled cohort study

    DEFF Research Database (Denmark)

    Liendgaard, Ulla Kristine Møller; við Streym, Susanna; Mosekilde, Leif

    2012-01-01

    weeks postpartum. The controls were followed in parallel. RESULTS: P-estradiol (E(2)), prolactin and 1,25-dihydroxyvitamin D (1,25(OH)(2)D) increased (p growth factor I (IGF......Pregnancy and lactation cause major changes in calcium homeostasis and bone metabolism. This population-based cohort study presents the physiological changes in biochemical indices of calcium homeostasis and bone metabolism during pregnancy and lactation INTRODUCTION: We describe physiological...... changes in calcium homeostasis, calcitropic hormones and bone metabolism during pregnancy and lactation. METHODS: We studied 153 women planning pregnancy (n = 92 conceived) and 52 non-pregnant, age-matched female controls. Samples were collected prior to pregnancy, once each trimester and 2, 16 and 36...

  14. 17beta-estradiol regulation of human growth hormone (hGH), insulin-like growth factor-I (IGF-I) and insulin-like growth factor binding protein-3 (IGFBP-3) axis in hypoestrogenic, hypergonadotropic women.

    Science.gov (United States)

    Milewicz, Tomasz; Krzysiek, Józef; Sztefko, Krystyna; Radowicki, Stanisław; Krzyczkowska-Sendrakowska, Magdalena

    2005-01-01

    Ovarian hormonal function may be as important contributing factor to hGH-IGF-I-IGFBP-3 axis as age. To examine plasma hGH, IGF-1 and IGFBP-3 levels in women with premature ovarian failure compared to healthy normal controls and postmenopausal ones. Group A-15 women with premature ovarian failure (POF) (mean: age 38.9+/-5.2 years, FSH 101.4+/-29.0 IU/l; 17beta-estradiol 22.5+/-14.6 ng/l). Group B consisted of 15 menopausal women (mean: age 54.7+/-2.7 years; FSH 81.9+/-32.1 IU/l; 17beta-estradiol 17.1+/- 8.0 ng/l). Group C - controls - 15 normally menstruating women (mean: age 37.1+/-9.0 years; FSH 6.2+/-1.0 IU/l; 17beta-estradiol 144.8+/-117.1 ng/l). Body mass and BMI were measured. Basic fasting plasma hGH, IGF-I, IGFBP-3, insulin, testosterone and LH as well as prolactin (PRL), FSH and estradiol were assessed by RIA kits. Statistical analysis. Shapiro-Wilk test, Mann-Whitney u-test, Spearman rang correlation coefficient, stepwise multiple regression. Mean serum IGF-I level was the lowest (phGH levels. Women in group A and C were younger (phGH levels in group C (r=-0.54; phGH/IGF-1 as well as IGFBP-3/hGH relations were found. Prolactin accounted for 69% of the variance in IGF-I level in the group B (p=0.003) and for 24% in group A (NS). Testosterone accounted for 88% (p=0.004) of the variance in IGF-I level in group B and IGFBP-3 was responsible for 86% (p=0.038) of the variance in IGF-I level in group C. Again IGFBP-3 was responsible for 47% (p=0.023) in group A and for 49% (p=0.04) in group B of the hGH variance. 17b-estradiol may be as important contributor to insulin-like growth factor-I (IGF-I) plasma level as age in hypoestrogenic, hypogonadotropic women.

  15. Growth hormone (GH) provocative retesting of 108 young adults with childhood-onset GH deficiency and the diagnostic value of insulin-like growth factor I (IGF-I) and IGF-binding protein-3

    DEFF Research Database (Denmark)

    Juul, A; Kastrup, K W; Pedersen, S A

    1997-01-01

    Serum levels of total insulin-like growth factor I (IGF-I) and IGF-binding protein-3 (IGFBP-3) reflect the endogenous GH secretion in healthy children and exhibit little diurnal variation, which makes them good diagnostic markers for screening of GH deficiency (GHD) in short children, although some...... controversy still exists. In adults, the diagnostic value of IGF-I and IGFBP-3 suspected of GHD has been reported in only a few studies. We performed a GH provocative test, using oral clonidine, in 108 patients who had previously been treated with GH during childhood (73 men and 35 women). Basal IGF......-I and IGFBP-3 levels were compared to those in 1237 healthy controls (312 controls > 18 yr) as well as to peak GH levels. Seventy-nine patients had peak GH values below a cut-off value of 7.5 micrograms/L (34 with isolated GHD), whereas 29 patients had a normal GH response (28 with previous isolated GHD), i...

  16. Parathyroid hormone blocks the stimulatory effect of insulin-like growth factor-I on collagen synthesis in cultured 21-day fetal rat calvariae

    International Nuclear Information System (INIS)

    Kream, B.E.; Petersen, D.N.; Raisz, L.G.

    1990-01-01

    We examined the interaction of parathyroid hormone (PTH) and recombinant human insulin-like growth factor I (IGF-I) on collagen synthesis in 21-day fetal rat calvariae as assessed by measuring the incorporation of [ 3 H]proline into collagenase-digestible protein. After 96 hours of culture, 10 nM PTH antagonized the stimulation of collagen synthesis and partially blocked the increase in dry weight produced by 10 nM IGF-I. The effect of PTH to block IGF-I stimulated collagen synthesis was observed in the central bone of calvariae and was mimicked by forskolin and phorbol 12-myristate 13-acetate, but not by 1,25-dihydroxyvitamin D3, transforming growth factor-alpha or dexamethasone. Our data are consistent with the concept that the direct effect of PTH is to inhibit basal CDP labeling and fully oppose IGF-I stimulated CDP labeling. The finding that this effect of PTH is mimicked by forskolin and PMA suggests that this block in IGF-I stimulation of CDP labeling involves both cAMP and protein kinase C mediated pathways

  17. Expression analysis of the insulin-like growth factors I and II during embryonic and early larval development of turbot ( Scophthalmus maximus)

    Science.gov (United States)

    Wen, Haishen; Qi, Qian; Hu, Jian; Si, Yufeng; He, Feng; Li, Jifang

    2015-04-01

    The insulin-like growth factors I and II (IGF-I and IGF-II) are important proteins involved in fish growth and development. Here, we report the isolation of IGF-II and expression analysis of IGFs in turbot Scophthalmus maximus, aiming to clarify their function in embryonic and larval development of fish. The deduced IGF-II gene is 808 bp in full length, which encodes a protein of 219 amino acids and is 93% similar with that of Paralichthys olicaceus in amino acid sequence. The tissue abundance and the expression pattern of IGFs in a turbot at early development stages were investigated via reverse transcription-polymer chain reaction. Result showed that the IGF-I and IGF-II genes were widely expressed in tissues of S. maximus. IGF-I was detected in all tissues except intestines with the highest level in liver, while IGF-II transcript presented in all tissues except muscle. At the stages of embryonic and larval development, the mRNA levels of IGFs sharply increased from the stage of unfertilized egg to post larva, followed by a decrease with larval development. However, there was an increase in IGF-I at the embryonic stage and IGF-II at the gastrula stage, respectively. These results suggested that IGFs play important roles in cell growth and division of the turbot. Our study provides reference data for further investigation of growth regulation in turbot, which can guarantee better understanding of the physiological role that IGFs play in fish.

  18. Antiproliferative and apoptotic effects of a specific anti-insulin-like growth factor I receptor single chain antibody on breast cancer cells.

    Science.gov (United States)

    Motallebnezhad, Morteza; Younesi, Vahid; Aghebati-Maleki, Leili; Nickho, Hamid; Safarzadeh, Elham; Ahmadi, Majid; Movassaghpour, Ali Akbar; Hosseini, Ahmad; Yousefi, Mehdi

    2016-11-01

    Insulin-like growth factor I receptor (IGF-IR) is expressed on breast cancer cells and involves in metastasis, survival, and proliferation. Currently, application of IGF-IR-targeting monoclonal antibodies (mAbs), alone or in combination with other drugs, is a promising strategy for breast cancer therapy. Single-chain fragment variable (scFv) antibodies have been introduced as appropriate tools for tumor-targeting purposes because of their advantages over whole antibodies. In the present study, we employed a naïve phage library and isolated scFvs against a specific epitope from extracellular domain of IGF-IR by panning process. The selected scFvs were further characterized using polyclonal and monoclonal phage ELISA, soluble monoclonal ELISA, and colony PCR and sequencing. Antiproliferative and apoptotic effects of selected scFv antibodies on breast cancer cell lines were also evaluated by MTT and Annexin V/PI assays. The results of ELISA indicated specific reactions of the isolated scFvs against the IGF-IR peptide, and analyses of PCR product and sequencing confirmed the presence of full length V H and Vκ inserts. Treatment of MCF7 and SKBR3 cells with anti-IGF-IR scFv led to a significant growth inhibition. The results also showed that scFv treatment significantly augmented trastuzumab growth inhibitory effects on SKBR3 cells. The percentage of the apoptotic MCF7 and SKBR3 cells after 24-h treatment with scFv was 39 and 30.70 %, respectively. Twenty-four-hour treatment with scFv in combination with trastuzumab resulted in 44.75 % apoptosis of SKBR3 cells. Taken together, our results demonstrate that the targeting of IGF-IR by scFv can be an effective strategy in the treatment of breast cancer and provide further evidence for effectiveness of dual targeting of HER2 and IGF-IR in breast cancer therapy.

  19. Glucose lowering effect of transgenic human insulin-like growth factor-I from rice: in vitro and in vivo studies

    Directory of Open Access Journals (Sweden)

    Sun Samuel SM

    2011-04-01

    Full Text Available Abstract Background Human insulin-like growth factor-I (hIGF-I is a growth factor which is highly resemble to insulin. It is essential for cell proliferation and has been proposed for treatment of various endocrine-associated diseases including growth hormone insensitivity syndrome and diabetes mellitus. In the present study, an efficient plant expression system was developed to produce biologically active recombinant hIGF-I (rhIGF-I in transgenic rice grains. Results The plant-codon-optimized hIGF-I was introduced into rice via Agrobacterium-mediated transformation. To enhance the stability and yield of rhIGF-I, the endoplasmic reticulum-retention signal and glutelin signal peptide were used to deliver rhIGF-I to endoplasmic reticulum for stable accumulation. We found that only glutelin signal peptide could lead to successful expression of hIGF-I and one gram of hIGF-I rice grain possessed the maximum activity level equivalent to 3.2 micro molar of commercial rhIGF-I. In vitro functional analysis showed that the rice-derived rhIGF-I was effective in inducing membrane ruffling and glucose uptake on rat skeletal muscle cells. Oral meal test with rice-containing rhIGF-I acutely reduced blood glucose levels in streptozotocin-induced and Zucker diabetic rats, whereas it had no effect in normal rats. Conclusion Our findings provided an alternative expression system to produce large quantities of biologically active rhIGF-I. The provision of large quantity of recombinant proteins will promote further research on the therapeutic potential of rhIGF-I.

  20. Fibroblast growth factor-mediated proliferation of central nervous system precursors depends on endogenous production of insulin-like growth factor I

    International Nuclear Information System (INIS)

    Drago, J.; Murphy, M.; Carroll, S.M.; Harvey, R.P.; Bartlett, P.F.

    1991-01-01

    Fibroblast growth factor stimulates proliferation and subsequent differentiation of precursor cells isolated from the neuroepithelium of embryonic day 10 mice in vitro. Here we show that fibroblast growth factor-induced proliferation is dependent on the presence of insulin-like growth factors (IGFs) and that IGF-I is endogenously produced by the neuroepithelial cells. Blocking of endogenous IGF-I activity with anti-IGF-I antibodies results in complete inhibition of fibroblast growth factor-mediated proliferation and in cell death. IGF-I alone acts as a survival agent. These observations correlate with the detection of transcripts for IGF-I and basic fibroblast growth factor in freshly isolated neuroepithelium and are consistent with an autocrine action of these factors in early brain development in vivo

  1. Decreased insulin-like growth factor-I and its receptor expression in the hippocampus and somatosensory cortex of the aged mouse.

    Science.gov (United States)

    Lee, Choong Hyun; Ahn, Ji Hyeon; Park, Joon Ha; Yan, Bing Chun; Kim, In Hye; Lee, Dae Hwan; Cho, Jeong-Hwi; Chen, Bai Hui; Lee, Jae-Chul; Cho, Jun Hwi; Lee, Yun Lyul; Won, Moo-Ho; Kang, Il-Jun

    2014-04-01

    Insulin-like growth factor-I (IGF-I) is a multifunctional polypeptide and has diverse effects on brain functions. In the present study, we compared IGF-I and IGF-I receptor (IGF-IR) immunoreactivity and their protein levels between the adult (postnatal month 6) and aged (postnatal month 24) mouse hippocampus and somatosensory cortex. In the adult hippocampus, IGF-I immunoreactivity was easily observed in the pyramidal cells of the stratum pyramidale in the hippocampus proper and in the granule cells of the granule cell layer of the dentate gyrus. In the adult somatosensory cortex, IGF-I immunoreactivity was easily found in the pyramidal cells of layer V. In the aged groups, IGF-I expression was dramatically decreased in the cells. Like the change of IGF-I immunoreactivity, IGF-IR immunoreactivity in the pyramidal and granule cells of the hippocampus and in the pyramidal cells of the somatosensory cortex was also markedly decreased in the aged group. In addition, both IGF-I and IGF-IR protein levels were significantly decreased in the aged hippocampus and somatosensory cortex. These results indicate that the apparent decrease of IGF-I and IGF-IR expression in the aged mouse hippocampus and somatosensory cortex may be related to age-related changes in the aged brain.

  2. Survivin as a Novel Biomarker in the Pathogenesis of Acne Vulgaris and Its Correlation to Insulin-Like Growth Factor-I.

    Science.gov (United States)

    Assaf, Hanan A; Abdel-Maged, Wafaa M; Elsadek, Bakheet E M; Hassan, Mohammed H; Adly, Mohamed A; Ali, Soher A

    2016-01-01

    Survivin, a member of the inhibitor of apoptosis protein family, has an important role in cell cycle regulation. Insulin-like growth factor-I (IGF-I) is a polypeptide hormone with wide range of biologic effects including stimulation of lipogenesis in sebaceous glands. Their overexpression in some fibrotic disorders suggests a possible implication of both IGF-I and survivin in the pathogenesis of acne and/or acne scars. The current study aimed to assess and correlate serum levels of IGF-I and survivin in patients with active acne vulgaris and postinflammatory acne scars and to evaluate their lesional expressions in comparison to healthy controls. Serum IGF-I and survivin were estimated using commercially available ELISA kits and their tissues expressions were investigated using Western blotting. Our findings suggest that IGF-I and survivin could play potential roles in the pathogenesis of active acne vulgaris and more importantly in postinflammatory acne scars with significant positive correlation coefficient between serum levels of IGF-I and survivin which support IGF-I-/PI3K-/AKT-mediated downregulation of nuclear expression of FoxO transcription factors resulting in enhanced survivin expression.

  3. Serum insulin-like growth factor I (IGF-I) and IGF-binding protein 3 (IGFBP-3) in IVF patients with polycystic ovary syndrome: correlations with outcome.

    Science.gov (United States)

    Schoyer, Katherine D; Liu, Hung-Ching; Witkin, Steven; Rosenwaks, Zev; Spandorfer, Steven D

    2007-07-01

    To evaluate serum insulin-like growth factor I (IGF-I) and IGF-binding protein 3 (IGFBP-3) levels during stimulation in polycystic ovary syndrome (PCOS) and control populations as factors predictive of IVF outcome. Observational study. Academic medical center-based IVF practice. Forty-three PCOS and 33 male-factor control patients undergoing IVF from 2002 to 2004. Treatment with a dual suppression protocol incorporating oral contraceptive pills (OCPs) and GnRH agonist suppression followed by low-dose gonadotropin therapy. The PCOS and control patients' serum IGF-I and IGFBP-3 levels were compared and correlated with IVF outcome. PCOS and control patients were comparable in terms of demographics and IVF outcome. In both, mean serum IGF-I levels increased during stimulation. PCOS patients whose IGF-I levels decreased from day 3 to day of hCG had a significantly higher mean number of immature oocytes retrieved (4.8 +/- 1.1 vs. 2.4 +/- 0.4; P=.02). IGFBP-3 levels increased during stimulation in PCOS patients but tended to decrease in control patients. In PCOS patients, an increase in IGFBP-3 levels during stimulation was associated with a greater likelihood of becoming pregnant (P=.03) and of ongoing pregnancy (P=.02). The bioavailability of IGF-I appears to play a key role in oocyte maturation in PCOS patients. Alterations in IGFBP-3 concentration during stimulation may be a critical mechanism in modulating IGF-I activity.

  4. Short-term effects of replacing milk with cola beverages on insulin-like growth factor-I and insulin–glucose metabolism:

    DEFF Research Database (Denmark)

    Hoppe, Camilla; Kristensen, Mette; Boiesen, Marlene

    2009-01-01

    In the Western world, a trend towards increased consumption of carbonated soft drinks combined with a decreasing intake of milk is observed. This may affect circulating insulin-like growth factor I (IGF-I) and fasting insulin, as seen in pre-pubertal children. The present study was designed...... given a low-Ca diet in two 10 d periods with 10 d washout in between. In one period, they drank 2·5 litres of Coca Colaw per day and the other period 2·5 litres of semi-skimmed milk. Serum IGF-I, IGFBP-3 (RIA), insulin (fluoro immunoassay) and glucose (Cobas) were determined at baseline and end point...... of each intervention period. Insulin resistance and b-cell function were calculated with the homeostasis model assessment. A decrease in serum IGF-I was observed in the cola period compared with the milk period (P,0·05). No effects of treatment were observed on IGFBP-3, IGF-I:IGFBP-3, insulin, glucose...

  5. Regulation of the pituitary tumor transforming gene by insulin-like-growth factor-I and insulin differs between malignant and non-neoplastic astrocytes

    International Nuclear Information System (INIS)

    Chamaon, Kathrin; Kirches, Elmar; Kanakis, Dimitrios; Braeuninger, Stefan; Dietzmann, Knut; Mawrin, Christian

    2005-01-01

    The reasons for overexpression of the oncogene pituitary tumor transforming gene (PTTG) in tumors are still not fully understood. A possible influence of the insulin-like growth factor I (Igf-I) may be of interest, since enhanced Igf-I signalling was reported in various human tumors. We examined the influence of Igf-I and insulin on PTTG expression in human astrocytoma cells in comparison to proliferating non-neoplastic rat embryonal astrocytes. PTTG mRNA expression and protein levels were increased in malignant astrocytes treated with Igf-I or insulin, whereas in rat embryonic astrocytes PTTG expression and protein levels increased only when cells were exposed to Igf-I. Enhanced transcription did not occur after treatment with inhibitors of phosphoinositol-3-kinase (PI3K) and mitogen-activated protein kinase (MAPK), blocking the two basic signalling pathways of Igf-I and insulin. In addition to this transcriptional regulation, both kinases directly bind to PTTG, suggesting a second regulatory route by phosphorylation. However, the interaction of endogenous PTTG with MAPK and PI3K, as well as PTTG phosphorylation were independent from Igf-I or insulin. The latter results were also found in human testis, which contains high PTTG levels as well as in nonneoplastic astrocytes. This suggest, that PI3K and MAPK signalling is involved in PTTG regulation not only in malignant astrocytomas but also in non-tumorous cells

  6. Animal protein intake, serum insulin-like growth factor I, and growth in healthy 2.5-y-old Danish children

    DEFF Research Database (Denmark)

    Hoppe, Camilla; Udam, Tina Rovenna; Lauritzen, Lotte

    2004-01-01

    Studies from developing countries indicate that intake of animal protein, especially of milk, is associated with greater velocity of linear growth in childhood. Whether the same association exists in industrialized countries, where protein intake is high, is not clear....

  7. Animal protein intake, serum insulin-like growth factor I, and growth in healthy 2.5-y-old Danish children

    DEFF Research Database (Denmark)

    Hoppe, Camilla; Udam, Tina Rovenna; Lauritzen, Lotte

    2004-01-01

    Studies from developing countries indicate that intake of animal protein, especially of milk, is associated with greater velocity of linear growth in childhood. Whether the same association exists in industrialized countries, where protein intake is high, is not clear.......Studies from developing countries indicate that intake of animal protein, especially of milk, is associated with greater velocity of linear growth in childhood. Whether the same association exists in industrialized countries, where protein intake is high, is not clear....

  8. Circulating insulin-like growth factor I in juvenile chum salmon: relationship with growth rate and changes during downstream and coastal migration in northeastern Hokkaido, Japan.

    Science.gov (United States)

    Kaneko, Nobuto; Taniyama, Natsumi; Inatani, Yu; Nagano, Yuta; Fujiwara, Makoto; Torao, Mitsuru; Miyakoshi, Yasuyuki; Shimizu, Munetaka

    2015-08-01

    Chum salmon (Oncorhynchus keta) migrate to the ocean in their first spring, and growth during early marine life is critical for survival. We examined the validity of circulating IGF-I and muscle RNA/DNA ratio as indices of growth rate using individually tagged juvenile chum salmon fed or fasted for 10 days. Serum IGF-I level was highly, positively correlated with individual growth rate. Muscle RNA/DNA ratio also showed a positive correlation, but its relation was not as high as that of IGF-I. We next measured these physiological parameters in chum salmon juveniles caught at river, estuary, port and nearshore of the northeastern Hokkaido, Japan, from May to June in 2013 and 2014, respectively. In both years, there was a trend that serum IGF-I levels were high in nearshore fish and low in river/estuarine fish in June. In contrast, muscle RNA/DNA ratio showed no clear temporal and spatial patterns. The present study shows that circulating IGF-I can be used as a growth index in juvenile chum salmon. Monitoring growth status using serum IGF-I suggests that growth of juvenile chum salmon in the survey area was activated when they left the coast.

  9. Successful 6-month endurance training does not alter insulin-like growth factor-I in healthy older men and women.

    Science.gov (United States)

    Vitiello, M V; Wilkinson, C W; Merriam, G R; Moe, K E; Prinz, P N; Ralph, D D; Colasurdo, E A; Schwartz, R S

    1997-05-01

    Lean body mass, strength, and endurance decline with advancing age, changes paralleled by declines in anabolic hormones, including growth hormone (GH) and insulin-like growth factor-I (IGF-I). Acute exercise has been shown to stimulate the GH/IGF-I axis, and long-term exercise increases GH. This study examined the effect of endurance training on IGF-I in healthy older men and women. Thirty-one healthy older men (66.9 +/- 1.0 yrs, mean +/- SEM) and 21 healthy older women (67.1 +/- 1.7 yrs) were randomized to either 3d/wk, 6-month endurance (ET3) or stretching/flexibility (SF3) protocols. Another group of 15 healthy older men (69.0 +/- 1.3 yrs) participated in a more intensive 5d/wk, 6-month endurance protocol (ET5). Before and after training, subjects were weight stabilized and participated in maximal exercise tolerance testing, body composition assessment, and fasting blood sampling. ET3 training resulted in a significant increase (14%) in maximal aerobic power (VO2max), significant decreases in body weight (BW), fat mass (FM), and waist/hip ratio (WHR), and a significant increase in fat-free mass (FFM). No significant VO2max or body composition changes were observed in the SF3 group. For the ET5 group, a significant increase (22%) in VO2max and significant decrease in BW, FM, and WHR were observed. No significant changes in IGF-I were observed for any of the three groups. Pre- versus post-training IGF-I values were very stable (r = .86, p decrease measures of body adiposity did not significantly increase basal levels of IGF-I in healthy older men and women.

  10. Influence of the toxicity of cryoprotective agents on the involvement of insulin-like growth factor-I receptor in surf clam (Spisula sachalinensis) larvae.

    Science.gov (United States)

    Choi, Youn Hee; Nam, Taek Jeong

    2014-01-01

    The signaling of insulin-like growth factor-I (IGF-I) is involved in the development, growth, reproduction and aging of vertebrates. However, few studies have investigated the involvement of IGF-I during states of extreme shock, such as those induced by potently toxic cryoprotective agents (CPAs) or low temperature conditions, in bivalves. We investigated the toxicity of CPAs and the potential relationship between larval viability and the IGF-I receptor (IGF-IR) after treatment with CPAs or freezing in surf clam (Spisula sachalinensis) larvae. The umbo larvae and different concentrations of CPAs (dimethyl sulfoxide, DMSO; ethylene glycol, EG) were used to investigate the toxicity of CPAs and the vitrification of surf clam larvae. The relationship between larval viability and the IGF-I receptor (IGF-IR) after treatment with CPAs or freezing was investigated using immunoblot analysis. An increase in concentration greater than 4M DMSO was fatal in larvae; however, 5M EG combined with a mixture of CPAs had no harmful effects. Moreover, live larvae immersed in a 5M EG solution remained intact and maintained their normal shape and organs. However, even though the larvae survived the CPA toxicity test, none of the vitrified larvae survived. After immersion into CPAs and vitrification, 97-kDa IGF-IR ß-subunits could be detected in all larvae; but tyrosine phosphorylation of the intracellular β-subunits was detected only in the control and live groups. IGF-IR was activated in the umbo larvae but not in dead surf clam larvae treated with CPA and frozen. Activation of IGF-IR has relevance to the umbo larval stage in live surf clams treated with CPAs.

  11. Red Deer Antler Extract Accelerates Hair Growth by Stimulating Expression of Insulin-like Growth Factor I in Full-thickness Wound Healing Rat Model.

    Science.gov (United States)

    Yang, ZhiHong; Gu, LiJuan; Zhang, DongLiang; Li, Zheng; Li, JingJie; Lee, MiRa; Wang, ChunYan; Wang, Zhen; Cho, JeongHee; Sung, Changkeun

    2012-05-01

    In order to investigate and evaluate the effects of red deer antlers on hair growth in the full-thickness wound healing model, Sprague-Dawley rats were given incision wounds through the full thickness of their dorsal skin and deer antler was applied for 40 days. At specified intervals thereafter (4, 8, 16, 32 and 40 days), the animals were sacrificed and the wound site skins were excised, processed, and sectioned. At post-injury days 16, 32 and 40, longer and more active new hair appeared around the healing wound of antler-treated skin. Histological studies showed that the antler extract markedly increases the depth, size, and number of hair follicles. Expression of IGF-I (insulin-like growth factor) mRNA was detected by RT-PCR and real time RT-PCR. The result showed that the expression of IGF-I (days 16, 32, and 40) was obviously up-regulated in antler-treated skins compared to control skins. Similar results were seen in the ELISA analysis to quantify the IGF-I expression. These results support the notion that wound healing can cause hair growth by enhancing the expression of IGF-I. Deer antler extract appears to have the potential to promote hair growth and could be used in hair growth products.

  12. Red Deer Antler Extract Accelerates Hair Growth by Stimulating Expression of Insulin-like Growth Factor I in Full-thickness Wound Healing Rat Model

    Directory of Open Access Journals (Sweden)

    ZhiHong Yang

    2012-05-01

    Full Text Available In order to investigate and evaluate the effects of red deer antlers on hair growth in the full-thickness wound healing model, Sprague-Dawley rats were given incision wounds through the full thickness of their dorsal skin and deer antler was applied for 40 days. At specified intervals thereafter (4, 8, 16, 32 and 40 days, the animals were sacrificed and the wound site skins were excised, processed, and sectioned. At post-injury days 16, 32 and 40, longer and more active new hair appeared around the healing wound of antler-treated skin. Histological studies showed that the antler extract markedly increases the depth, size, and number of hair follicles. Expression of IGF-I (insulin-like growth factor mRNA was detected by RT-PCR and real time RT-PCR. The result showed that the expression of IGF-I (days 16, 32, and 40 was obviously up-regulated in antler-treated skins compared to control skins. Similar results were seen in the ELISA analysis to quantify the IGF-I expression. These results support the notion that wound healing can cause hair growth by enhancing the expression of IGF-I. Deer antler extract appears to have the potential to promote hair growth and could be used in hair growth products.

  13. An investigation of fetal, postnatal and childhood growth with insulin-like growth factor I and binding protein 3 in adulthood.

    Science.gov (United States)

    Ben-Shlomo, Y; Holly, J; McCarthy, A; Savage, P; Davies, D; Gunnell, D; Davey Smith, G

    2003-09-01

    Weight at birth and adult height are positively associated with cancer risk. These patterns may be mediated by the insulin-like growth factor (IGF) axis. We have examined whether pre- and postnatal growth patterns have a long-term influence on adult IGF-I and IGFBP-3 levels. A follow-up study of a randomized controlled trial of milk supplementation in pregnancy and childhood. A total of 951 individuals took part in a study of diet and growth in South Wales between 1972 and 1974 followed up from birth until their mid-20s. Anthopometric measures at birth, postnatally up to 5 years of age and in adulthood, and serum measures of IGF-I and IGF-I to IGFBP-3 ratio at mean age of 25 years. A total of 63 subjects (70%) provided blood for analysis. We found no association between birth dimensions and adult IGF-I. Subjects who exhibited 'catch-down growth' had lower IGF-I levels (P-value for trend 0.02). Adult height was positively related to IGF-I, for every one standard deviation increase in adult height, IGF-I increased by 3.75 ng/dl (95% CI 0.46-7.08, P = 0.03). Adiposity was inversely associated with the IGF-I and IGF-I to IGFBP-3 ratio and positively associated with IGFBP-3. The strength of the associations increased with age. Downward centile crossing at any time in childhood was associated with lower IGF-I whilst the highest levels were observed in subjects who were tall throughout their early life course. Adult height remained a significant predictor of IGF-I even after adjustment for earlier growth. Our results indicate that IGF-I levels in early adulthood are associated with patterns of childhood growth as well as adult stature and adiposity. These associations suggest the IGFs may contribute to anthropometric associations with cancer risk.

  14. Ghrelin, insulin-like growth factor I and adipocytokines concentrations in born small for gestational age prepubertal children after the catch-up growth.

    Science.gov (United States)

    Stawerska, Renata; Szałapska, Małgorzata; Hilczer, Maciej; Lewiński, Andrzej

    2016-08-01

    In children born small for gestational age (SGA) with catch-up growth, a higher risk of insulin resistance (IR) and cardiovascular diseases is noted. Ghrelin stimulates a growth hormone (GH) secretion and regulates lipid and carbohydrate metabolism. We assessed gherlin's influence on achieving normal height and the occurrence of metabolic complications in SGA children. Ghrelin, insulin-like growth factor type I (IGF-I), leptin, adiponectin, resistin, glucose, insulin and lipid concentrations were analysed in 134 prepubertal children in four groups: normal-height SGA, short SGA, normal-height born appropriate for gestational age (AGA) and short AGA. Ghrelin and IGF-I concentrations were significantly higher while adiponectin - lower in normal-height SGA comparing to others. The increased production of ghrelin and IGF-I seems to be an adaptive mechanism to achieve normal growth in SGA children. The significance of high ghrelin and low adiponectin concentrations, observed in normal-height prepubertal SGA children, requires elucidation, with reference to the development of metabolic complications.

  15. Changes of plasma growth hormone, insulin-like growth factors-I, thyroid hormones, and testosterone concentrations in embryos and broiler chickens incubated under monochromatic green light

    Directory of Open Access Journals (Sweden)

    Lin Zhang

    2014-07-01

    Full Text Available Previous studies showed that monochromatic green light stimuli during embryogenesis accelerated posthatch body weight and pectoral muscle growth of broilers. In this experiment, we further investigated whether the regulation of broiler embryonic or posthatch growth by green light stimulus during incubation is associated with the changes of some important hormones at different ages of embryos and broiler chickens. Fertile broiler eggs (Arbor Acres, n=880 were pre-weighed and randomly assigned 1 of 2 incubation treatment groups: i dark condition (control group, and ii monochromatic green light group (560 nm. The monochromatic lighting systems sourced from light-emitting diode lamps were equalised at the intensity of 15 lux (lx at eggshell level. The dark condition was set as a commercial control from day one until hatching. After hatch, 120 day-old male chicks from each group were housed under white light with an intensity of 30 lx at bird-head level. Compared with the dark condition, chicks incubated under the green light showed significantly higher growth hormone (GH levels from 19 d of embryogenesis (E19 to 5 d of posthatch (H5, and higher plasma insulinlike growth factor (IGF-I levels from both E17 to E19 and H3 to H35. No significant differences were found in plasma thyroxine, triiodothyronine, and testosterone in embryos or hatched birds between the 2 groups. These results indicate that somatotropic axis hormones (GH and IGF-I may be the most important contributor to chicken growth promoted by green light stimuli during embryogenesis.

  16. Insulin-like growth factors I and II in starry flounder (Platichthys stellatus): molecular cloning and differential expression during embryonic development.

    Science.gov (United States)

    Xu, Yongjiang; Zang, Kun; Liu, Xuezhou; Shi, Bao; Li, Cunyu; Shi, Xueying

    2015-02-01

    In order to elucidate the possible roles of insulin-like growth factors I and II (IGF-I and IGF-II) in the embryonic development of Platichthys stellatus, their cDNAs were isolated and their spatial expression pattern in adult organs and temporal expression pattern throughout embryonic development were examined by quantitative real-time PCR assay. The IGF-I cDNA sequence was 1,268 bp in length and contained an open reading frame (ORF) of 558 bp, which encoded 185 amino acid residues. With respect to IGF-II, the full-length cDNA was 899 bp in length and contained a 648-bp ORF, which encoded 215 amino acid residues. The amino acid sequences of IGF-I and IGF-II exhibited high identities with their fish counterparts. The highest IGF-I mRNA level was found in the liver for both sexes, whereas the IGF-II gene was most abundantly expressed in female liver and male liver, gill, and brain. The sex-specific and spatial expression patterns of IGF-I and IGF-II mRNAs are thought to be related to the sexually dimorphic growth and development of starry flounder. Both IGF-I and IGF-II mRNAs were detected in unfertilized eggs, which indicated that IGF-I and IGF-II were parentally transmitted. Nineteen embryonic development stages were tested. IGF-I mRNA level remained high from unfertilized eggs to low blastula followed by a significant decrease at early gastrula and then maintained a lower level. In contrast, IGF-II mRNA level was low from unfertilized eggs to high blastula and peaked at low blastula followed by a gradual decrease. Moreover, higher levels of IGF-I mRNA than that of IGF-II were found from unfertilized eggs to high blastula, vice versa from low blastula to newly hatched larva, and the different expression pattern verified the differential roles of IGF-I and IGF-II in starry flounder embryonic development. These results could help in understanding the endocrine mechanism involved in the early development and growth of starry flounder.

  17. Hepatic mRNA expression and plasma levels of insulin-like growth factor-I (IGF-I in broiler chickens selected for different growth rates

    Directory of Open Access Journals (Sweden)

    Poliana Fernanda Giachetto

    2004-01-01

    Full Text Available The hepatic expression and plasma concentrations of IGF-I were investigated in three broiler chicken strains selected for different growth rates (HP-Hubbard-Pettersen, a fast growing strain; NN-Naked-neck, a strain with an intermediate growth rate and a heterozygous genotype, and C-Caipira, a slow growing crossbred strain. The chickens were studied at 1, 21 and 42 days of age and had free access to food throughout the study. Hepatic IGF-I mRNA expression was assessed by dot blot analysis using a randomly labeled chicken IGF-I cDNA as the probe and plasma IGF-I concentrations were assayed by radioimmunoassay. The hepatic levels of IGF-I mRNA increased from 1 to 21 days of age in all strains, with NN chickens showing a higher (p < 0.05 IGF-I expression than the other strains. Plasma IGF-I concentrations increased (p < 0.05 with broiler chicken age, but there were no significant differences among the strains. These results indicate that despite differences in the growth rates among the strains, the changes in the expression of IGF-I mRNA in liver and in the plasma levels of IGF-I were independent of broiler chicken strain, but varied with chicken age.

  18. Inactivation of Rac1 reduces Trastuzumab resistance in PTEN deficient and insulin-like growth factor I receptor overexpressing human breast cancer SKBR3 cells.

    Science.gov (United States)

    Zhao, Yong; Wang, Zhishan; Jiang, Yiguo; Yang, Chengfeng

    2011-12-26

    Drug resistance remains to be a big challenge in applying anti-HER2 monoclonal antibody Trastuzumab for treating breast cancer with HER2 overexpression. Amplification of insulin-like growth factor I receptor (IGF-IR) and deletion of tumor suppressor phosphatase and tensin homolog (PTEN) are implicated in Trastuzumab resistance, however, the underlying mechanisms have not been clearly defined. Activation of Rac1, a member of Rho GTPase family, is capable of causing cytoskeleton reorganization, regulating gene expression and promoting cell proliferation. To investigate the mechanism of Trastuzumab resistance, PTEN knockdown and IGF-IR overexpressing stable cell lines were generated in HER2 overexpression human breast cancer SKBR3 cells. Rac1 was highly activated in PTEN deficient and IGF-IR overexpressing Trastuzumab-resistant cells in a HER2-independent manner. Inactivation of Rac1 by using a Rac1 inhibitor NSC23766 or siRNA knocking down the expression of Tiam1, a guanine nucleotide exchange factor for Rac, significantly reduced Trastuzumab resistance in SKBR3 cells. Inhibition of Rac1 had no effect on the levels of phosphor-HER2 and phosphor-Akt, but significantly decreased the levels of cyclin D1 in Trastuzumab-resistant cells. Inhibition of Akt with an Akt inhibitor also significantly reduced Trastuzumab resistance. However, simultaneous inhibition of both Rac1 and Akt resulted in a significantly more decrease of Trastuzumab resistance than inactivation of Rac1 or Akt alone. These results suggest that Rac1 activation is critically involved in Trastuzumab resistance caused by PTEN deletion or IGF-IR overexpression. Simultaneous inhibition of Rac1 and Akt may represent a promising strategy in reducing Trastuzumab resistance in HER2 overexpression breast cancer. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  19. Development of receptors for insulin and insulin-like growth factor-I in head and brain of chick embryos: Autoradiographic localization

    International Nuclear Information System (INIS)

    Bassas, L.; Girbau, M.; Lesniak, M.A.; Roth, J.; de Pablo, F.

    1989-01-01

    In whole brain of chick embryos insulin receptors are highest at the end of embryonic development, while insulin-like growth factor-I (IGF-I) receptors dominate in the early stages. These studies provided evidence for developmental regulation of both types of receptors, but they did not provide information on possible differences between brain regions at each developmental stage or within one region at different embryonic ages. We have now localized the specific binding of [125I]insulin and [125I]IGF-I in sections of head and brain using autoradiography and computer-assisted densitometric analysis. Embryos have been studied from the latter part of organogenesis (days 6 and 12) through late development (day 18, i.e. 3 days before hatching), and the binding patterns have been compared with those in the adult brain. At all ages the binding of both ligands was to discrete anatomical regions. Interestingly, while in late embryos and adult brain the patterns of [125I]insulin and [125I] IGF-I binding were quite distinct, in young embryos both ligands showed very similar localization of binding. In young embryos the retina and lateral wall of the growing encephalic vesicles had the highest binding of both [125I]insulin and [125I]IGF-I. In older embryos, as in the adult brain, insulin binding was high in the paleostriatum augmentatum and molecular layer of the cerebellum, while IGF-I binding was prominent in the hippocampus and neostriatum. The mapping of receptors in a vertebrate embryo model from early prenatal development until adulthood predicts great overlap in any possible function of insulin and IGF-I in brain development, while it anticipates differential localized actions of the peptides in the mature brain

  20. Receptors for insulin-like growth factors I and II: autoradiographic localization in rat brain and comparison to receptors for insulin

    International Nuclear Information System (INIS)

    Lesniak, M.A.; Hill, J.M.; Kiess, W.; Rojeski, M.; Pert, C.B.; Roth, J.

    1988-01-01

    Receptors for insulin-like growth factor I (IGF-I) in rat brain were visualized using autoradiography with [125I]IGF-I. The binding of the labeled peptide was competed for fully by high concentrations of unlabeled IGF-I. At intermediate concentrations of unlabeled peptide the binding of [125I]IGF-I was competed for by unlabeled IGF-I more effectively than by IGF-II or insulin, which is typical of receptors for IGF-I. Essentially every brain section shows specific binding of IGF-I, and the pattern of binding of IGF-I to its receptors correlated well with the cytoarchitectonic structures. In parallel studies we showed that [125I]IGF-II was bound to tissue sections of rat brain and that the binding was competed for by an excess of unlabeled IGF-II. However, intermediate concentrations of unlabeled peptides gave inconclusive results. To confirm that the binding of [125I]IGF-II was to IGF-II receptors, we showed that antibodies specific for the IGF-II receptor inhibited the binding of labeled IGF-II. Furthermore, the binding of the antibody to regions of the brain section, visualized by the application of [125I]protein-A, gave patterns indistinguishable from those obtained with [125I]IGF-II alone. Again, the binding was very widely distributed throughout the central nervous system, and the patterns of distribution corresponded well to the underlying neural structures. Densitometric analysis of the receptors enabled us to compare the distribution of IGF-I receptors with that of IGF-II receptors as well as retrospectively with that of insulin receptors

  1. Effects of insulin-like growth factor-I and platelet-rich plasma on sciatic nerve crush injury in a rat model.

    Science.gov (United States)

    Emel, Erhan; Ergün, Selma Sönmez; Kotan, Dilcan; Gürsoy, Esra Başar; Parman, Yeşim; Zengin, Asli; Nurten, Asiye

    2011-02-01

    Local administration of insulin-like growth factor-I (IGF-I) has been shown to increase the rate of axon regeneration in crush-injured and freeze-injured rat sciatic nerves. Local administration of platelet-rich plasma (PRP) has been also shown to have a measurable effect on facial nerve regeneration after transection in a rat model. The objective of the study was to compare the effects of locally administered IGF-I and PRP on the parameters of the Sciatic Function Index (SFI), sensory function (SF), axon count, and myelin thickness/axon diameter ratio (G-ratio) in a rat model of crush-injured sciatic nerves. The right sciatic nerve of Wistar albino rats (24 animals) was crushed using a Yasargil-Phynox aneurysm clip for 45 minutes. All animals were randomly divided into 3 groups: Group 1 (control group) was treated with saline, Group 2 was treated with IGF-I, and Group 3 was treated with PRP. Injections were performed using the tissue expander's injection port with a connecting tube directed at the crush-injured site. Functional recovery was assessed with improvement in the SFI. Recovery of sensory function was using the pinch test. Histopathological examination was performed 3 months after the injury. The SFI showed an improved functional recovery in the IGF-I-treated animals (Group 2) compared with the saline-treated animals (Group 1) 30 days after the injury. In IGF-I-treated rats, sensory function returned to the baseline level significantly faster than in saline-treated and PRP-treated rats as shown in values between SF-2 and SF-7. The G-ratios were found to be significantly higher in both experimental groups than in the control group. This study suggests that the application of IGF-I to the crush-injured site may expedite the functional recovery of paralyzed muscle by increasing the rate of axon regeneration.

  2. Effect of whole-body vibration and insulin-like growth factor-I on muscle paralysis-induced bone degeneration after botulinum toxin injection in mice.

    Science.gov (United States)

    Niehoff, Anja; Lechner, Philipp; Ratiu, Oana; Reuter, Sven; Hamann, Nina; Brüggemann, Gert-Peter; Schönau, Eckhard; Bloch, Wilhelm; Beccard, Ralf

    2014-04-01

    Botulinum toxin A (BTX)-induced muscle paralysis results in pronounced bone degradation with substantial bone loss. We hypothesized that whole-body vibration (WBV) and insulin-like growth factor-I (IGF-I) treatment can counteract paralysis-induced bone degradation following BTX injections by activation of the protein kinase B (Akt) signaling pathway. Female C57BL/6 mice (n = 60, 16 weeks) were assigned into six groups (n = 10 each): SHAM, BTX, BTX+WBV, BTX+IGF-I, BTX+WBV+IGF-I, and a baseline group, which was killed at the beginning of the study. Mice received a BTX (1.0 U/0.1 mL) or saline (SHAM) injection in the right hind limb. The BTX+IGF-I and BTX+WBV+IGF-I groups obtained daily subcutaneous injections of human IGF-I (1 μg/day). The BTX+WBV and BTX+WBV+IGF-I groups underwent WBV (25 Hz, 2.1 g, 0.83 mm) for 30 min/day, 5 days/week for 4 weeks. Femora were scanned by pQCT, and mechanical properties were determined. On tibial sections TRAP staining, static histomorphometry, and immunohistochemical staining against Akt, phospho-Akt, IGF-IR (IGF-I receptor), and phospho-IGF-IR were conducted. BTX injection decreased trabecular and cortical bone mineral density. The WBV and WBV+IGF-I groups showed no difference in trabecular bone mineral density compared to the SHAM group. The phospho-IGF-IR and phospho-Akt stainings were not differentially altered in the injected hind limbs between groups. We found that high-frequency, low-magnitude WBV can counteract paralysis-induced bone loss following BTX injections, while we could not detect any effect of treatment with IGF-I.

  3. Levels of insulin, insulin-like growth factor-I and thyroid hormones in relation to the body condition score changes in periparturient dairy cows

    Directory of Open Access Journals (Sweden)

    Fratrić Natalija

    2013-01-01

    Full Text Available The objective of this study was to determine the levels of insulin, insulin like growth factor I (IGF-I and thyroid hormones in relation to the body condition score (BCS of periparturient dairy cows. The study was carried out on twenty Holstein-Friesian dairy cows with average milk production of 7000 L/305 days in the previous lactation, parity ranging from 2-4. All cows were BCS scored during the early dry period, 7±3 days before and after parturition. Based on the BCS at the early dry period, cows were divided in two groups: cows with high BCS (3.75- 4.25, HBCS, n=10, and cows with moderate BCS (2.75-3.75, MBCS, n=10. Blood samples were taken at the time of BCS evaluation. Concentrations of insulin, IGF-I, triiodothyroinine (T3 and thyroxine (T4 were determined by radioimmunoassay (RIA, INEP-Zemun, Serbia. Statistical differences between mean values were determined using Student t-test (p0.05. IGF-I level in HBCS cows at days 7±3 before calving was significantly higher (16.28±3.07:11.76±2.28, p<0.01, with a reverse relationship after calving (3.77±1.64:8.46±2.37, p<0.01. Insulin level was significantly lower at 7±3 days before calving in HBCS cows (16.26±4.60:20.18±4.96mIU/L, p<0.05. Thyroid hormones levels were significantly lower in HBCS group et all examined periods. [Projekat Ministarstva nauke Republike Srbije, br. III 46002 i br. 31003

  4. Involvement of G proteins in the effect of insulin-like growth factor I on gonadotropin-induced rat granulosa cell differentiation.

    Science.gov (United States)

    He, H; Herington, A C; Roupas, P

    1994-03-01

    Insulin-like growth factor I (IGF-I) promotes gonadotropin-induced granulosa cell differentiation and proliferation. In order to investigate whether guanine nucleotide binding proteins (G proteins) may be linked, directly or indirectly, to some of the actions of IGF, the effects of cholera toxin (CT) and pertussis toxin (PT) on the enhancement by IGF-I of PMSG (pregnant mare serum gonadotropin)-induced rat granulosa cell differentiation have been studied. This was done by the determination of progesterone production, aromatase activity and cAMP accumulation after a 48 h incubation with PMSG, IGF-I and PMSG plus IGF-I in cells treated with either CT or PT. Both CT and PT treatment stimulated PMSG-induced progesterone production in granulosa cells after 48 h of culture with PMSG. CT treatment also stimulated aromatase activity in cells treated with PMSG and increased cAMP secretion under basal conditions (untreated cells) and in PMSG treated cells. Both CT and PT increased the stimulation by IGF-I of PMSG-induced progesterone production after 48 h of culture with PMSG plus IGF-I. Furthermore, CT augmented the enhancement by IGF-I of PMSG-induced aromatase activity and cAMP accumulation. In the absence of PMSG, CT did not increase steroidogenesis either alone or in the presence of IGF-I within the time frame studied even though CT was able to stimulate cAMP accumulation in untreated and IGF-I treated cells. These results suggest that G proteins have a role in the signalling cascade involved in gonadotropin-induced granulosa cell differentiation measured as PMSG-mediated steroidogenesis.(ABSTRACT TRUNCATED AT 250 WORDS)

  5. Synergistic effect of fadrozole and insulin-like growth factor-I on female-to-male sex reversal and body weight of broiler chicks.

    Science.gov (United States)

    Mohammadrezaei, Mohammad; Toghyani, Majid; Gheisari, Abbasali; Toghyani, Mehdi; Eghbalsaied, Shahin

    2014-01-01

    The aim of this study was to investigate the effects of Fadrozole hydrochloride and recombinant human insulin-like growth factor I (rhIGF-I) on female-to-male sex reversal, hatching traits, and body weight of broiler chickens. On the third day of incubation, fertile eggs were randomly assigned to five experimental groups comprising (i) Fadrozole (0.1 mg/egg), (ii) rhIGF-I (100 ng/egg), (iii) Fadrozole (0.1 mg/egg) + rhIGF-I (100 ng/egg), (iv) vehicle injection (10 mM acetic acid and 0.1% BSA), and (v) non-injected eggs. Eggs in the rhIGF-I-injected groups showed the mode of hatching time at the 480th hour of incubation, 12 hours earlier compared to the other groups, with no statistically significant difference in mortality and hatchability. On Day 1 and 42 of production, 90% of genetically female chicks were masculinized using Fadrozole treatment, while 100% female-to-male phenotypic sex reversal was observed in the Fadrozole+rhIGF-I group. Fadrozole equalized the body weight of both genders, although rhIGF-I was effective on the body weight of male chicks only. Interestingly, combined rhIGF-I and Fadrozole could increase the body weight in both sexes compared to the individual injections (Pbody weight of masculinized chickens via Fadrozole could be equal to their genetically male counterparts, and (iv) the IGF-I effectiveness, specifically along with the application of aromatase inhibitors in female chicks, indicates that estrogen synthesis could be a stumbling block for the IGF-I action mechanism in female embryos.

  6. Systemic administration of kainic acid induces selective time dependent decrease in [125I]insulin-like growth factor I, [125I]insulin-like growth factor II and [125I]insulin receptor binding sites in adult rat hippocampal formation

    International Nuclear Information System (INIS)

    Quirion, R.; Chabot, J.-G.; Dore, S.; Seto, D.; Kar, S.

    1997-01-01

    Administration of kainic acid evokes acute seizure in hippocampal pathways that results in a complex sequence of functional and structural alterations resembling human temporal lobe epilepsy. The structural alterations induced by kainic acid include selective loss of neurones in CA1-CA3 subfields and the hilar region of the dentate gyrus followed by sprouting and permanent reorganization of the synaptic connections of the mossy fibre pathways. Although the neuronal degeneration and process of reactive synaptogenesis have been extensively studied, at present little is known about means to prevent pathological conditions leading to kainate-induced cell death. In the present study, to address the role of insulin-like growth factors I and II, and insulin in neuronal survival as well as synaptic reorganization following kainate-induced seizure, the time course alterations of the corresponding receptors were evaluated. Additionally, using histological preparations, the temporal profile of neuronal degeneration and hypertrophy of resident astroglial cells were also studied. [ 125 I]Insulin-like growth factor I binding was found to be decreased transiently in almost all regions of the hippocampal formation at 12 h following treatment with kainic acid. The dentate hilar region however, exhibited protracted decreases in [ 125 I]insulin-like growth factor I receptor sites throughout (i.e. 30 days) the study. [ 125 I]Insulin-like growth factor II receptor binding sites in the hippocampal formation were found to be differentially altered following systemic administration of kainic acid. A significant decrease in [ 125 I]insulin-like growth factor II receptor sites was observed in CA1 subfield and the pyramidal cell layer of the Ammon's horn at all time points studied whereas the hilar region and the stratum radiatum did not exhibit alteration at any time. A kainate-induced decrease in [ 125 I]insulin receptor binding was noted at all time points in the molecular layer of the

  7. Growth and obesity and its association with plasma level of steroid hormones and insulin-like growth factor-I (IGF-I) in Slovak female students.

    Science.gov (United States)

    Zatko, T; Matejovicova, B; Boledovicova, M; Vondrakova, M; Bezakova, A; Sirotkin, A V

    2013-01-01

    The aim of the present study was to examine the possible role of steroid hormones and insulin-like growth factor 1 (IGF-I) in the control of human growth and obesity. We measured plasma level of progesterone, testosterone, estradiol and IGF-I in 301 young women at different stages of their ovarian cycle, and compared them to the standard morphometric indexes of their growth and obesity - body height, body weight, abdomen circumstance and waist to hip ratio (WHR). The ovarian cycle-dependent changes in plasma progesterone and estradiol, but not in testosterone and IGF-I level were found. Young women with higher body height had significantly higher plasma level of estradiol, testosterone and IGF-I, but not of progesterone, compared to subjects with lower body height in both follicular and luteal phases of the ovarian cycle. Subjects with a higher body weight had significantly higher plasma estradiol and progesterone, but not testosterone and IGF-I than subjects with lower body weight in both follicular and luteal phases of ovarian cycle. Women with a higher abdomen circumference had significantly lower plasma estradiol, but not the other hormones than the subjects with lower abdomen circumference. Women with higher WHR index had significantly higher plasma level of estradiol, but not other hormones than subjects with lower WHR index in both follicular and luteal phases of ovarian cycle. The present observations suggests: (1) that luteal phase of the women ovarian cycle is characterised by a dramatically increase in both progesterone and estradiol, but not in testosterone and IGF-I release, (2) that in human females growth can be up-regulated by testosterone, estradiol and IGF-I, but not by progesterone, (3) that body mass can be up-regulated by progesterone and estradiol, but not by testosterone or IGF-I, and (4) that women obesity (high WHR, but not abdomen circumference) can be promoted by estradiol, but not by other steroid hormones or IGF-I (Tab. 1, Fig. 4, Ref

  8. Massive weight loss restores 24-hour growth hormone release profiles and serum insulin-like growth factor-I levels in obese subjects

    DEFF Research Database (Denmark)

    Rasmussen, M H; Hvidberg, A; Juul, A

    1995-01-01

    using anthropometric measurements and dual energy x-ray absorptiometry scanning (DXA). In the obese subjects, 24-h spontaneous GH release profiles and the GH responses to insulin-induced hypoglycemia and L-arginine as well as basal IGF-I levels and the IGF-I/IGFBP-3 molar ratio were decreased, whereas...... profiles, the decreased GH responses to insulin-induced hypoglycemia and L-arginine, the decreased basal IGF-I levels and IGF-I/IGFBP-3 molar ratio, as well as the elevated insulin levels were returned to normal after a massive weight loss in the obese subjects. In conclusion, the present study has shown...

  9. Effects of an endurance cycling competition on resting serum insulin-like growth factor I (IGF-I) and its binding proteins IGFBP-1 and IGFBP-3

    Science.gov (United States)

    Chicharro, J; Lopez-Calderon, A; Hoyos, J; Martin-Velasco, A; Villa, G; Villanua, M; Lucia, A

    2001-01-01

    Objectives—To determine whether consecutive bouts of intense endurance exercise over a three week period alters serum concentrations of insulin-like growth factor I (IGF-I) and/or its binding proteins. Methods—Seventeen professional cyclists (mean (SEM) VO2MAX, 74.7 (2.1) ml/kg/min; age, 27 (1) years) competing in a three week tour race were selected as subjects. Blood samples were collected at each of the following time points: t0 (control, before the start of competition), t1 (end of first week), and t3 (end of third week). Serum levels of both total and free IGF-I and IGF binding proteins 1 and 3 (IGFBP-1 and IGFBP-3) were measured in each of the samples. Cortisol levels were measured in nine subjects. Results—A significant (p<0.01) increase was found in total IGF-I and IGFBP-1 at both t1 and t3 compared with to (IGF-I: 110.9 (17.7), 186.8 (12.0), 196.9 (14.7) ng/ml at t0, t1, and t3 respectively; IGFBP-1: 54.6 (6.6), 80.6 (8.0), and 89.2 (7.9) ng/ml at t0, t1, and t3 respectively). A significant (p<0.01) decrease was noted in free IGF-I at t3 compared with both to and t1 (t0: 0.9 (0.1) ng/ml; t1: 0.9 (0.1) ng/ml; t3: 0.7 (0.1) ng/ml); in contrast, IGFBP-3 levels remained stable throughout the race. Conclusions—It would appear that the increase in circulating levels of both IGF-I and its binding protein IGFBP-1 is a short term (one week) endocrine adaptation to endurance exercise. After three weeks of training, total IGF-I and IGFBP-1 remained stable, whereas free IGF-I fell below starting levels. Key Words: cycling; insulin-like growth factor; exercise; endurance; binding proteins PMID:11579061

  10. Low serum levels of free and total insulin-like growth factor I (IGF-I) in patients with anorexia nervosa are not associated with increased IGF-binding protein-3 proteolysis

    DEFF Research Database (Denmark)

    Støving, R K; Flyvbjerg, A; Frystyk, J

    1999-01-01

    Patients with anorexia nervosa (AN) are GH resistant, with elevated GH levels and low serum levels of total insulin-like growth factor I (IGF-I). IGF-I action is modulated by IGF-binding proteins (IGFBPs), and a variety of catabolic states has been characterized by the presence of increased IGFBP-3...

  11. Free and total insulin-like growth factor I (IGF-I), IGF-binding protein-1 (IGFBP-1), and IGFBP-3 and their relationships to the presence of diabetic retinopathy and glomerular hyperfiltration in insulin-dependent diabetes mellitus

    NARCIS (Netherlands)

    J.A.M.J.L. Janssen (Joseph); M.L. Jacobs (Marloes); F.H.M. Derkx (Frans); R.F.A. Weber (Robert); A-J. van der Lely (Aart-Jan); S.W.J. Lamberts (Steven)

    1997-01-01

    textabstractThe existing literature on serum insulin-like growth factor I (IGF-I) levels in insulin-dependent diabetes mellitus (IDDM) is conflicting. Free IGF-I may have greater physiological and clinical relevance than total IGF-I. Recently, a validated method has

  12. Interaction of Mechanical Load with Growth Hormone (GH) and Insulin-Like Growth Factor I (IGF-I) on Slow-Twitch Skeletal Muscle and Bone

    Science.gov (United States)

    Linderman, Jon K.; Gosselink, Kristin L.; Wang, Tommy J.; Mukku, Venkat R.; Grindeland, Richard E.

    1994-01-01

    Exogenous humoral growth factors, combined with increased mechanical loading, reportedly induce hypertrophy of fast-, but not slow-twitch skeletal muscles, and have little effect in attenuating atrophy of slow-twitch muscle associated with exposure to microgravity in animals with intact neuroendocrine systems. These observations suggest that anabolic adjuvants and muscle tension do not interact to stimulate growth or maintenance of slow-twitch skeletal muscle. The purpose of the present study was to determine whether a chronic increase in mechanical loading (synergistic ablation) or hindlimb unweighting (hindlimb suspension) interact with exogenous GH and IGF-I (Genentech, So San Francisco, CA) in the slow-twitch soleus muscles of female rats (approx. 250 g). Bilateral ablation of the plantaris and gastrocnemius muscles induced 38% and 40% increases in the absolute (mg/pair) and relative (mg/100 g body weight) weights of the soleus, respectively (p less than or = 0.05), in ambulatory rats. GH and IGF-I interacted with chronic loading to increase absolute soleus mass an additional 20% (p less than or = 0.05), and mixed and myofibrillar protein contents an additional 12% and 7%, respectively (NS). In contrast, hindlimb suspension (HLS) resulted in 20% and 18% decreases in the absolute and relative weights of the soleus, respectively (p less than or = 0.05); GH and IGF-I did not spare loss of soleus mass or protein content in HLS rats. HLS decreased tibial plate thickness approx. 11% (p less than or = 0.05), but not weights of the tibia or femus. GH and IGF-I increased tibial plate thickness approx. 30% (p less than or = 0.05), in ambulatory and HLS rats, and increased femur and tibial weights 12% (p less than or = 0.05) and 8% (NS), respectively, in ambulatory rats, but had no effect in HLS rats. Results of the present investigation suggest that GH and IGF-I can stimulate hypertrophy of slow-twitch skeletal muscle when chronically overloaded, but can also stimulate

  13. Human placental growth hormone, insulin-like growth factor I and -II, and insulin requirements during pregnancy in type 1 diabetes

    DEFF Research Database (Denmark)

    Fuglsang, Jens; Lauszus, Finn; Flyvbjerg, Allan

    2003-01-01

    PGH was not correlated to the increase in insulin requirements, nor was any consistent relationship revealed during each gestational period. In conclusion, our study suggests a role for hPGH in the regulation of both IGFs and fetal growth in type 1 diabetes. In contrast, the increase in insulin requirements during...... between hPGH and IGF-I in type 1 diabetes mellitus has not been investigated thoroughly. Furthermore, hPGH may be involved in the development of insulin resistance during pregnancy. In this prospective, longitudinal study, 51 type 1 diabetic subjects were followed with repeated blood sampling during...... pregnancy in type 1 diabetic subjects could not be related to hPGH levels....

  14. Effects of two oral contraceptives on plasma levels of insulin-like growth factor I (IGF-I) and growth hormone (hGH).

    Science.gov (United States)

    Balogh, A; Kauf, E; Vollanth, R; Gräser, G; Klinger, G; Oettel, M

    2000-11-01

    In 18 healthy women, the effect of two oral contraceptives (OCs) on insulin-like growth factor (IGF-I) and its binding protein-3 (IGFBP-3) and growth hormone (hGH) plasma level were studied before and after intake of either of two OC formulations over 21 days, one containing 2 mg dienogest and 0.03 mg ethinylestradiol (group A) and the other 0.125 mg levonorgestrel and 0.03 mg ethinylestradiol (group B). There was a reduction of the mean IGF-I concentration of 30% (p = 0.008) in the women receiving dienogest-containing pills and 12% (p = 0.006) in women taking the levonogestrel-containing preparation. This difference between drug groups was statistically significant (p = 0.002). A correlation between the control values and the basal-treatment difference (r = 0.945; p = 0.000) was observed only in women of group A. Between basal and treatment cycles the mean plasma levels of hGH remained unchanged in both groups tested, but the 23.5-h integrated mean hGH plasma concentrations (AUC(0-23.5h)) were significantly elevated by 36% (p = 0.016) in comparison to basal values before treatment only in women receiving the levonorgestrel-containing pills. Also, in the women who received the dienogest-containing preparation, the changes of integrated mean plasma level were inversely associated with the control values (r = -0.723; p = 0.025). Neither in group A nor in group B was the mean plasma level of IGFB-3 changed. the results of the present analysis indicate that hormonal contraceptives can modulate the GH and IGF-I-axis in the reproductive age. Probably the androgenic progestogen levonorgestrel (0.125 mg/day) opposes the estrogen-induced action. In the women who took the dienogest-containing formulations (anti-androgenic progestogen-group A), the extent of individual changes (hGh and IGF-I) depends on the basal level prior to pill intake. Further studies, especially of long-term intake of OCs, are necessary to confirm these results and to assess the practical relevance for

  15. Impact of the growth hormone receptor exon 3 deletion gene polymorphism on glucose metabolism, lipids, and insulin-like growth factor-I levels during puberty

    DEFF Research Database (Denmark)

    Sørensen, Kaspar; Aksglaede, Lise; Munch-Andersen, Thor

    2009-01-01

    the impact of the GHRd3 gene polymorphism on insulin sensitivity, insulin secretion, lipids, and IGF-I levels in healthy children and adolescents. DESIGN: This was cross-sectional and was part of the COPENHAGEN puberty study. SETTING: The study was conducted at a tertiary center for pediatric endocrinology......-I levels. RESULTS: Insulin secretion was higher in children and adolescents with a least one GHRd3 allele, even after adjustment for age, sex, pubertal stage, and insulin sensitivity (P = 0.018). Disposition index was higher in GHRd3-positive subjects (P = 0.026). In addition, the GHRd3 allele......CONTEXT: The GH/IGF-I axis has major impact on insulin sensitivity and insulin secretion. Recently a polymorphism in the GH receptor gene (GHR), a genomic deletion of exon 3 (GHRd3), has been linked to increased responsiveness to GH. OBJECTIVE: The objective of the present study was to evaluate...

  16. Relationship of serum insulin-like growth factor I (IGF-I) with nutritional status in pediatric patients with malignant diseases--a single Romanian center experience.

    Science.gov (United States)

    Chinceşan, Mihaela Ioana; Mărginean, Oana; Pitea, Ana-Maria; Dobreanu, Minodora

    2013-10-01

    The aim of this study was to analyze insulin-like growth factor I (IGF-I) serum level in pediatric patients with cancer compared with pediatric patients with nononcological diseases and to assess the relationship between IGF-I and nutritional status of oncological patients. From January 2009 to July 2012, we assessed 151 consecutively hospitalized patients in a tertiary emergency pediatric hospital. The patients were divided into two groups: group I, consisting of patients with malignant diseases (64 patients), and group II, the control group, consisting of 87 age- and gender-matched patients with different pediatric diseases. The anthropometric parameters (weight, height, body mass index, middle upper arm circumference (MUAC), and tricipital skinfold thickness (TST) and biochemical parameters (proteins, albumin, and total IGF-I) were comparatively evaluated at the diagnosis and after intensive chemotherapy in the malignant group. Anthropometric and biochemical parameters in group I were significantly different from those in group II for height, MUAC, TST, total proteins, and albumin (p patients with malignant diseases and 5 out of 87 patients in the control group had malnutrition. IGF-I in patients with cancer was much lower than in the control group (median 48.3 ng/ml, range 25.00-662.00 ng/ml vs 129.00 ng/ml, range 25.00-745.00 ng/ml) (p = 0.014). We found a positive correlation between IGF-I, MUAC, and TST at the diagnosis of the malignant disease. Also, we identified positive correlations between IGF-I, protein, and albumin. Serum IGF-I levels in cancer patients were significantly lower at diagnosis than after chemotherapy (48.3 ng/ml, range 25.00-662.00 ng/ml vs 110.0 ng/ml, range 25.00-573.00 ng/ml; p = 0.04). IGF-I seems to be an accurate biochemical parameter used in malnutrition assessment of children with cancer. IGF-I correlated with the anthropometric parameters of the arm, serum protein, and albumin. These parameters most accurately characterize the

  17. Characterization of insulin-like growth factor I receptors in the median eminence of the brain and their modulation by food restriction

    International Nuclear Information System (INIS)

    Bohannon, N.J.; Corp, E.S.; Wilcox, B.J.; Figlewicz, D.P.; Dorsa, D.M.; Baskin, D.G.

    1988-01-01

    High affinity binding sites for 125I-labeled [Thr59]insulin-like growth factor I (IGF-I) were measured in rat median eminence by in vitro autoradiography with slide-mounted sections of frozen rat brain. Specific binding of 0.1 nM iodo-[Thr59]IGF-I to brain slices reached maximum by 12 h at 4 C and was unchanged at 24 h. Densitometry by computer digital image analysis of autoradiographic images indicated that specific binding of iodo-[Thr59]IGF-I to the median eminence was reversible. The specificity of binding was evaluated with competition of iodo-[Thr59]IGF-I with unlabeled [Thr59]IGF-I, rat IGF-II (multiplication-stimulating activity), and porcine insulin. All were recognized by the binding site, but the rank order of potency was [Thr59]IGF-I greater than IGF-II greater than insulin. Somatostatin was completely ineffective. Further, an antibody against the rat IGF-II receptor did not block binding of iodo-[Thr59]IGF-I to the median eminence. Fourteen days of food restriction (75% of food intake of controls) resulted in significant weight loss and reduction of plasma immunoreactive IGF-I in six food-restricted rats (0.9 +/- 0.1 U/ml) compared with values in six controls (2.6 +/- 0.5 U/ml; P less than 0.001). Binding of 125I-labeled [Thr59]IGF-I in the median eminence was significantly increased in the food-restricted rats, primarily due to an increase in the concentration of iodo-[Thr59]IGF-I-binding sites in the median eminence; the affinity (Kd) of binding was unchanged. The results indicate that the median eminence has type I IGF-I receptors, which become more numerous under metabolic conditions associated with decreased caloric intake and lowered plasma IGF-I levels

  18. Increased abundance of insulin/insulin-like growth factor-I hybrid receptors in skeletal muscle of obese subjects is correlated with in vivo insulin sensitivity.

    Science.gov (United States)

    Federici, M; Porzio, O; Lauro, D; Borboni, P; Giovannone, B; Zucaro, L; Hribal, M L; Sesti, G

    1998-08-01

    We reported that in noninsulin-dependent diabetes melitus (NIDDM) patients expression of insulin/insulin-like growth factor I (IGF-I) hybrid receptors is increased in insulin target tissues. Whether this is a defect associated with NIDDM or represents a generalized abnormality associated with insulin resistant states is still unsettled. To address this, we applied a microwell-based immunoassay to measure abundance of insulin receptors, type 1 IGF receptors, and hybrid receptors in muscle of eight normal and eight obese subjects. Maximal insulin binding to insulin receptors was lower in obese than in control subjects (B/T = 1.8 +/- 0.20 and 2.6 +/- 0.30; P < 0.03, respectively) and was negatively correlated with insulinemia (r = -0.60; P < 0.01). Maximal IGF-I binding to type 1 IGF receptors was higher in obese than in controls (B/T = 1.9 +/- 0.20 and 0.86 +/- 0.10; P < 0.0001, respectively) and was negatively correlated with plasma IGF-I levels (r = -0.69; P < 0.003). Hybrid receptor abundance was higher in obese than in normal subjects (B/T = 1.21 +/- 0.14 and 0.44 +/- 0.06; P < 0.0003, respectively) and was negatively correlated with insulin binding (r = -0.60; P < 0.01) and positively correlated with IGF-I binding (r = 0.92; P < 0.0001). Increased abundance of hybrids was correlated with insulinemia (r = 0.70; P < 0.002) and body mass index (r = 0.71; P < 0.0019), whereas it was negatively correlated with in vivo insulin sensitivity measured by ITT (r = -0.67; P < 0.016). These results indicate that downregulation of insulin receptors or upregulation of type 1 IGF receptors because of changes in plasma insulin and IGF-I levels may result in modifications in hybrid receptor abundance.

  19. Synergistic effect of fadrozole and insulin-like growth factor-I on female-to-male sex reversal and body weight of broiler chicks.

    Directory of Open Access Journals (Sweden)

    Mohammad Mohammadrezaei

    Full Text Available The aim of this study was to investigate the effects of Fadrozole hydrochloride and recombinant human insulin-like growth factor I (rhIGF-I on female-to-male sex reversal, hatching traits, and body weight of broiler chickens. On the third day of incubation, fertile eggs were randomly assigned to five experimental groups comprising (i Fadrozole (0.1 mg/egg, (ii rhIGF-I (100 ng/egg, (iii Fadrozole (0.1 mg/egg + rhIGF-I (100 ng/egg, (iv vehicle injection (10 mM acetic acid and 0.1% BSA, and (v non-injected eggs. Eggs in the rhIGF-I-injected groups showed the mode of hatching time at the 480th hour of incubation, 12 hours earlier compared to the other groups, with no statistically significant difference in mortality and hatchability. On Day 1 and 42 of production, 90% of genetically female chicks were masculinized using Fadrozole treatment, while 100% female-to-male phenotypic sex reversal was observed in the Fadrozole+rhIGF-I group. Fadrozole equalized the body weight of both genders, although rhIGF-I was effective on the body weight of male chicks only. Interestingly, combined rhIGF-I and Fadrozole could increase the body weight in both sexes compared to the individual injections (P<0.05. These findings revealed that (i IGF-I-treated chicken embryos were shown to be an effective option for overcoming the very long chicken deprivation period, (ii the simultaneous treatment with Fadrozole and IGF-I could maximize the female-to-male sex reversal chance, (iii the increase in the body weight of masculinized chickens via Fadrozole could be equal to their genetically male counterparts, and (iv the IGF-I effectiveness, specifically along with the application of aromatase inhibitors in female chicks, indicates that estrogen synthesis could be a stumbling block for the IGF-I action mechanism in female embryos.

  20. Effects of phorbol ester and staurosporine on the actions of insulin-like growth factor-I on rat ovarian granulosa cells.

    Science.gov (United States)

    He, H; Herington, A C; Roupas, P

    1995-02-01

    Insulin-like growth factor I (IGF-I) is able to stimulate ovarian granulosa cell steroidogenesis induced by gonadotopins. This gonadotropin-induced potentiation of IGF-I action appears to be due, at least in part, to a gonadotropin-induced increase in membrane-bound IGF-I receptor number and/or decrease in extracellular IGF binding proteins (IGFBPs). Protein kinase C (PKC) has recently been reported to inhibit gonadotropin-induced steroidogenesis in rat ovarian granulosa cells. The role of PKC in the effects of IGF-I on gonadotropin action, however, is unknown. In this study, the effects of phorbol 12-myristate 13-acetate (PMA, a PKC activator) and staurosporine (ST, a PKC inhibitor) on IGF-I action were studied using immature rat ovarian granulosa cells. Activation of PKC by PMA did not affect steroidogenesis or cAMP secretion in cells treated with or without IGF-I. On the other hand, inhibition of PKC by ST alone (10(-9)-10(-7)m) led to an increase in progesterone production in a dose- and time-dependent manner without affecting cAMP secretion. In the presence, but not absence, of ST, IGF-I was able to stimulate progesterone production in the absence of any gonadotropin. PMA decreased ST-induced steroidogenesis and essentially abolished ST-potentiated IGF-I stimulation of steroidogenesis, suggesting the effects of ST on IGF-I action involved a PKC-dependent mechanism. Unlike gonadotropin, ST did not change IGF-I receptor binding. However, ST significantly decreased a major IGF binding protein (IGFBP, ∼30kDa) which is likely to be IGFBP-5, whereas it increased a minor IGFBP (∼24kDa) which is likely to be IGFBP-4. Both effects of ST were dose- and time-dependent. Furthermore, ST inhibited the expression of mRNA for IGFBP-5 suggesting that ST decreased IGFBP-5 levels by inhibiting its transcription and/or decreasing the stability of its mRNA. Interestingly, ST also decreased mRNA levels of IGFBP-4 despite a significant increase in secreted IGFBP-4 levels. The

  1. High-intensity interval training (HIIT) increases insulin-like growth factor-I (IGF-I) in sedentary aging men but not masters' athletes: an observational study.

    Science.gov (United States)

    Herbert, Peter; Hayes, Lawrence D; Sculthorpe, Nicholas; Grace, Fergal M

    2017-03-01

    The aim of this investigation was to examine the impact high-intensity interval training (HIIT) on serum insulin-like growth factor-I (IGF-I) in active compared with sedentary aging men. 22 lifetime sedentary (SED; 62 ± 2 years) and 17 masters' athletes (LEX; 60 ± 5 years) were recruited to the study. As HIIT requires preconditioning exercise in sedentary cohorts, the study required three assessment phases; enrollment (phase A), following preconditioning exercise (phase B), and post-HIIT (phase C). Serum IGF-I was determined by electrochemiluminescent immunoassay. IGF-I was higher in LEX compared to SED at baseline (p = 0.007, Cohen's d = 0.91), and phase B (p = 0.083, Cohen's d = 0.59), with only a small difference at C (p = 0.291, Cohen's d = 0.35). SED experienced a small increase in IGF-I following preconditioning from 13.1 ± 4.7 to 14.2 ± 6.0 μg·dl -1 (p = 0.376, Cohen's d = 0.22), followed by a larger increase post-HIIT (16.9 ± 4.4 μg·dl -1 ), which was significantly elevated compared with baseline (p = 0.002, Cohen's d = 0.85), and post-preconditioning (p = 0.005, Cohen's d = 0.51). LEX experienced a trivial changes in IGF-I from A to B (18.2 ± 6.4 to 17.2 ± 3.7 μg·dl -1 [p = 0.538, Cohen's d = 0.19]), and a small change post-HIIT (18.4 ± 4.1 μg·dl -1 [p = 0.283, Cohen's d = 0.31]). Small increases were observed in fat-free mass in both groups following HIIT (p HIIT with preconditioning exercise abrogates the age associated difference in IGF-I between SED and LEX, and induces small improvements in fat-free mass in both SED and LEX.

  2. Epithelial-to-mesenchymal transition in breast cancer: a role for insulin-like growth factor I and insulin-like growth factor–binding protein 3?

    Directory of Open Access Journals (Sweden)

    Zielinska HA

    2015-01-01

    Full Text Available Hanna A Zielinska,1 Amit Bahl,2 Jeff MP Holly,1 Claire M Perks1 1IGFs and Metabolic Endocrinology Group, School of Clinical Sciences, University of Bristol, Learning and Research Building, Southmead Hospital, Bristol, UK; 2Department of Clinical Oncology, Bristol Haematology and Oncology Centre, University Hospitals Bristol, Bristol, UK Abstract: Evidence indicates that for most human cancers the problem is not that gene mutations occur but is more dependent upon how the body deals with damaged cells. It has been estimated that only about 1% of human cancers can be accounted for by unmistakable hereditary cancer syndromes, only up to 5% can be accounted for due to high-penetrance, single-gene mutations, and in total only 5%–15% of all cancers may have a major genetic component. The predominant contribution to the causation of most sporadic cancers is considered to be environmental factors contributing between 58% and 82% toward different cancers. A nutritionally poor lifestyle is associated with increased risk of many cancers, including those of the breast. As nutrition, energy balance, macronutrient composition of the diet, and physical activity levels are major determinants of insulin-like growth factor (IGF-I bioactivity, it has been proposed that, at least in part, these increases in cancer risk and progression may be mediated by alterations in the IGF axis, related to nutritional lifestyle. Localized breast cancer is a manageable disease, and death from breast cancer predominantly occurs due to the development of metastatic disease as treatment becomes more complicated with poorer outcomes. In recent years, epithelial-to-mesenchymal transition has emerged as an important contributor to breast cancer progression and malignant transformation resulting in tumor cells with increased potential for migration and invasion. Furthermore, accumulating evidence suggests a strong link between components of the IGF pathway, epithelial

  3. Role of receptors for epidermal growth factor and insulin-like growth factors I and II in the differentiation of rat mammary glands from lactogenesis I to lactogenesis II.

    Science.gov (United States)

    Bussmann, L E; Bussmann, I M; Charreau, E H

    1996-07-01

    In addition to ovarian steroids and lactogenic hormones from the placenta and pituitary, growth factors control the growth and differentiation of mammary glands. Lactogenesis II at the end of pregnancy is under the control of progesterone. Ovariectomy results in a significant decrease in the number of receptors for epidermal growth factor (EGF) and insulin-like growth factor I (IGF-I) and an increase in IGF-II binding sites in mammary gland acini of rats, without affecting the affinity for their respective ligand. Although concentrations of EGF, IGF-I and IGF-II receptors are regulated by oestradiol and progesterone, replacement treatment with ovarian steroids after ovariectomy showed that receptor concentrations do not mediate the restraint on lactogenesis. Progesterone treatment, which inhibits the onset of lactogenesis II, did not restore EGF receptor concentrations to control values, and the presence of oestradiol was required to reverse the effect of ovariectomy. Oestradiol, which potentiates the effect of ovariectomy on milk synthesis, increases IGF-I receptor concentrations. IGF-II receptor concentrations, after the different steroid treatments, were consistent with the steroid effect on milk synthesis. The changes observed in the concentrations of these growth factor receptors at the onset of mammary gland secretion are not considered to affect the progesterone block to lactogenesis II, but rather are a consequence of the shift of the hormonal and, hence, physiological status of the gland.

  4. The interactions between hypothalamic-pituitary-adrenal axis activity, testosterone, insulin-like growth factor I and abdominal obesity with metabolism and blood pressure in men.

    Science.gov (United States)

    Rosmond, R; Björntorp, P

    1998-12-01

    To examine potential interactions between abdominal obesity, endocrine, metabolic and hemodynamic perturbations. A subgroup of 284 men from a population sample of 1040 at the age of 51 y. Anthropometric measurements included body mass index (BMI, kg/m2), waist/hip circumference ratio (WHR) and abdominal sagittal diameter (D). Endocrine measurements were a modified, low dose (0.5 mg) dexamethasone suppression test (Dex), testosterone (T) and insulin-like growth factor I (IGF-I). Overnight fasting values of blood glucose, serum insulin, triglycerides, total, low and high density lipoprotein cholesterol, as well as resting heart rate and blood pressure were also determined. Arbitrary subdivisions of the men were performed to obtain subgroups of low T and IGF-I values (lowest decile, borderlines low density lipoprotein cholesterol, were then found in subgroups with different endocrine profiles. These included men with a blunted Dex test with low T or IGF-I values, as well as men with a normal Dex test and low or normal T or IGF-I values. In addition, a group with isolated low Dex suppression, as well as another group without endocrine abnormalities, showed such relationships. These findings suggest that, in men, obesity factors are associated with metabolic and hemodynamic complications with or without the presence of perturbations of hypothalamic-pituitary-adrenal axis (HPA) regulation or low T or growth hormone secretion. In order to generate hypotheses concerning the nature of the impact of the endocrine perturbations in abdominal obesity and its metabolic complications, path analyses were performed, testing different models. These models included the endocrine measurements (Dex test, T and IGF-I), the WHR and D (representing abdominal distribution of fat), BMI (representing obesity), as well as insulin and triglyceride values (representing metabolic perturbations). The results showed a satisfactory fit (goodness-of-fit index: 0.945 - 1.0) for the path diagrams: Dex

  5. Insulin-Like Growth Factor I Produces an Antidepressant-Like Effect and Elicits N-Methyl-D-Aspartate Receptor Independent Long-Term Potentiation of Synaptic Transmission in Medial Prefrontal Cortex and Hippocampus.

    Science.gov (United States)

    Burgdorf, Jeffrey; Zhang, Xiao-lei; Colechio, Elizabeth M; Ghoreishi-Haack, Nayereh; Gross, Amanda; Kroes, Roger A; Stanton, Patric K; Moskal, Joseph R

    2015-09-15

    Growth factors play an important role in regulating neurogenesis and synapse formation and may be involved in regulating the antidepressant response to conventional antidepressants. To date, Insulin-like growth factor I (IGFI) is the only growth factor that has shown antidepressant properties in human clinical trials. However, its mechanism of action remains unclear. The antidepressant-like effect of a single IV dose of IGFI was determined using a chronic unpredictable stress paradigm in the rat Porsolt, sucrose preference, novelty-induced hypophagia, and ultrasonic vocalization models. The dependence of the medial prefrontal cortex for these effects was determined by direct medial prefrontal cortex injection followed by Porsolt testing as well as IGFI receptor activation in the medial prefrontal cortex following an optimal IV antidepressant-like dose of IGFI. The effect of IGFI on synaptic transmission and long-term potentiation (LTP) of synaptic strength was assessed in the hippocampus and medial prefrontal cortex. The dependence of these effects on IGFI and AMPA receptor activation and protein synthesis were also determined. IGFI produced a rapid-acting and long-lasting antidepressant-like effect in each of the depression models. These effects were blocked by IGFI and AMPA receptor antagonists, and medial prefrontal cortex was localized. IGFI robustly increased synaptic strength in the hippocampus and medial prefrontal cortex and these effects were IGFI receptor and protein synthesis-dependent but N-methyl-d-aspartate receptor independent. IGFI also robustly facilitated hippocampal metaplasticity 24 hours postdosing. These data support the conclusion that the antidepressant-like effects of IGFI are mediated by a persistent, LTP-like enhancement of synaptic strength requiring both IGFIR activation and ongoing protein synthesis. © The Author 2015. Published by Oxford University Press on behalf of CINP.

  6. 2010 responsible growth report

    International Nuclear Information System (INIS)

    2010-01-01

    The report addresses several development and growth perspectives for AREVA: its integrated business model, the synergy and complementarities between nuclear and renewable energies, the sustainable development dimension of its industrial development, its sales revenue result, the reduction of its environmental footprint, its development on all continents, its balanced governance, the simplification of its capital structure, and the actions performed by its Foundation. Then, it discusses ten challenges for the company: ensuring safety and performance throughout the reactor life cycle, making the EPR reactor a standard of safety, maintaining relations based on trust with our stake holders, staying in the lead, accelerating the development of renewable energies, being a trusted partner to growing economies, being a model in mine management, promoting sustainable, effective and safe recycling of used fuel, improving performance continuously, offering development prospects to all employees. It briefly presents ten successes achieved in 2010 and indicates ten sustainable development commitments. Document in French and in English

  7. Production and characterization of recombinantly derived peptides and antibodies for accurate determinations of somatolactin, growth hormone and insulin-like growth factor-I in European sea bass (Dicentrarchus labrax).

    Science.gov (United States)

    de Celis, S Vega-Rubín; Gómez-Requeni, P; Pérez-Sánchez, J

    2004-12-01

    A specific radioimmunoassay (RIA) for European sea bass (Dicentrarchus labrax) growth hormone (GH) was developed and validated. For this purpose, a stable source of GH was produced by means of recombinant DNA technology in a bacteria system. The identity of the purified protein (ion exchange chromatography) was demonstrated by Western blot and a specific GH antiserum was raised in rabbit. In Western blot and RIA system, this antiserum recognized specifically native and recombinant GH, and it did not cross-react with fish prolactin (PRL) and somatolactin (SL). In a similar way, a specific polyclonal antiserum against the now available recombinant European sea bass SL was raised and used in the RIA system to a sensitivity of 0.3 ng/ml (90% of binding of tracer). Further, European sea bass insulin-like growth factor-I (IGF-I) was cloned and sequenced, and its high degree of identity with IGF-I peptides of barramundi, tuna, and sparid fish allowed the use of a commercial IGF-I RIA based on barramundi IGF-I antiserum. These assay tools assisted for the first time accurate determinations of SL and GH-IGF-I axis activity in a fish species of the Moronidae family. Data values were compared to those found with gilthead sea bream (Sparus aurata), which is currently used as a Mediterranean fish model for growth endocrinology studies. As a characteristic feature, the average concentration year round of circulating GH in growing mature males of European sea bass was higher than in gilthead sea bream. By contrast, the average concentration of circulating SL was lower. Concerning to circulating concentration of IGF-I, the measured plasma values for a given growth rate were also lower in European sea bass. These findings are discussed on the basis of a different energy status that might allowed a reduced but more continuous growth in European sea bass.

  8. c-Src, Insulin-Like Growth Factor I Receptor, G-Protein-Coupled Receptor Kinases and Focal Adhesion Kinase are Enriched Into Prostate Cancer Cell Exosomes.

    Science.gov (United States)

    DeRita, Rachel M; Zerlanko, Brad; Singh, Amrita; Lu, Huimin; Iozzo, Renato V; Benovic, Jeffrey L; Languino, Lucia R

    2017-01-01

    It is well known that Src tyrosine kinase, insulin-like growth factor 1 receptor (IGF-IR), and focal adhesion kinase (FAK) play important roles in prostate cancer (PrCa) development and progression. Src, which signals through FAK in response to integrin activation, has been implicated in many aspects of tumor biology, such as cell proliferation, metastasis, and angiogenesis. Furthermore, Src signaling is known to crosstalk with IGF-IR, which also promotes angiogenesis. In this study, we demonstrate that c-Src, IGF-IR, and FAK are packaged into exosomes (Exo), c-Src in particular being highly enriched in Exo from the androgen receptor (AR)-positive cell line C4-2B and AR-negative cell lines PC3 and DU145. Furthermore, we show that the active phosphorylated form of Src (Src pY416 ) is co-expressed in Exo with phosphorylated FAK (FAK pY861 ), a known target site of Src, which enhances proliferation and migration. We further demonstrate for the first time exosomal enrichment of G-protein-coupled receptor kinase (GRK) 5 and GRK6, both of which regulate Src and IGF-IR signaling and have been implicated in cancer. Finally, Src pY416 and c-Src are both expressed in Exo isolated from the plasma of prostate tumor-bearing TRAMP mice, and those same mice have higher levels of exosomal c-Src than their wild-type counterparts. In summary, we provide new evidence that active signaling molecules relevant to PrCa are enriched in Exo, and this suggests that the Src signaling network may provide useful biomarkers detectable by liquid biopsy, and may contribute to PrCa progression via Exo. J. Cell. Biochem. 118: 66-73, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  9. Forkhead box A1 (FOXA1) is a key mediator of insulin-like growth factor I (IGF-I) activity.

    Science.gov (United States)

    Potter, Adam S; Casa, Angelo J; Lee, Adrian V

    2012-01-01

    The insulin-like growth factor receptor (IGF-IR) has been implicated in a number of human tumors, including breast cancer. Data from human breast tumors has demonstrated that IGF-IR is over-expressed and hyper-phosphorylated. Additionally, microarray analysis has shown that IGF-I treatment of MCF7 cells leads to a gene signature comprised of induced and repressed genes, which correlated with luminal B tumors. FOXA1, a forkhead family transcription factor, has been shown to be crucial for mammary ductal morphogenesis, similar to IGF-IR, and expressed at high levels in luminal subtype B breast tumors. Here, we investigated the relationship between FOXA1 and IGF-I action in breast cancer cells. We show that genes regulated by IGF-I are enriched for FOXA1 binding sites, and knock down of FOXA1 blocked the ability of IGF-I to regulate gene expression. IGF-I treatment of MCF7 cells increased the half-life of FOXA1 protein and this increase in half-life appeared to be dependent on canonical IGF-I signal transduction through both MAPK and AKT pathways. Finally, knock down of FOXA1 led to a decreased ability of IGF-I to induce proliferation and protect against apoptosis. Together, these results demonstrate that IGF-I can increase the stability of FOXA1 protein expression and place it as a critical mediator of IGF-I regulation of gene expression and IGF-I-mediated biological responses. Copyright © 2011 Wiley Periodicals, Inc.

  10. The proto-oncogene product c-Crk associates with insulin receptor substrate-1 and 4PS. Modulation by insulin growth factor-I (IGF) and enhanced IGF-I signaling.

    Science.gov (United States)

    Beitner-Johnson, D; Blakesley, V A; Shen-Orr, Z; Jimenez, M; Stannard, B; Wang, L M; Pierce, J; LeRoith, D

    1996-04-19

    The Crk proto-oncogene product is an SH2 and SH3 domain-containing adaptor protein which we have previously shown to become rapidly tyrosine phosphorylated in response to stimulation with insulin-like growth factor I (IGF-I) in NIH-3T3 cells. In order to further characterize the role of Crk in the IGF-I signaling pathway, NIH-3T3 and 293 cells were stably transfected with an expression vector containing the Crk cDNA. The various resultant 3T3-Crk clones expressed Crk at approximately 2-15-fold higher levels than parental 3T3 cells. In 3T3-Crk cells, Crk immunoreactivity was detected in insulin receptor substrate-1 (IRS-1) immunoprecipitates. Stimulation with IGF-I resulted in a dissociation of Crk protein from IRS-1. In contrast, the association of the related adaptor protein Grb2 with IRS-1 was enhanced by IGF-I stimulation. Similar results were obtained in stably transfected 293-Crk cells, which express both IRS-1 and the IRS-1-related signaling protein 4PS. In these cells, IRS-1 and 4PS both associated with Crk, and this association was also decreased by IGF-I treatment, whereas the association of Grb2 with IRS-1 and 4PS was enhanced by IGF-I. Overexpression of Crk also enhanced IGF-I-induced mitogenesis of NIH-3T3 cells, as measured by [3H]thymidine incorporation. The levels of IGF-I-induced mitogenesis were proportional to the level of Crk expression. These results suggest that Crk is a positive effector of IGF-I signaling, and may mediate its effects via interaction with IRS-1 and/or 4PS.

  11. Plasma insulin-like growth factor I levels are higher in depressive and anxiety disorders, but lower in antidepressant medication users

    NARCIS (Netherlands)

    Bot, Mariska; Milaneschi, Yuri; Penninx, Brenda W J H; Drent, Madeleine L

    It has been postulated that many peripheral and (neuro)biological systems are involved in psychiatric disorders such as depression. Some studies found associations of depression and antidepressant treatment with insulin-like growth factor 1 (IGF-I) - a pleiotropic hormone affecting neuronal growth,

  12. Host factor I, Hfq, binds to Escherichia coli ompA mRNA in a growth rate-dependent fashion and regulates its stability

    DEFF Research Database (Denmark)

    Vytvytska, O; Jakobsen, J S; Balcunaite, G

    1998-01-01

    RNA. In hfq mutant cells with a deficient Hfq gene product, the RNA-binding activity is missing, and analysis of the ompA mRNA showed that the growth-rate dependence of degradation is lost. Furthermore, the half-life of the ompA mRNA is prolonged in the mutant cells, irrespective of growth rate. Hfq has...

  13. Changes in calcitropic hormones, bone markers and insulin-like growth factor I (IGF-I) during pregnancy and postpartum: a controlled cohort study.

    Science.gov (United States)

    Møller, U K; Streym, S; Mosekilde, L; Heickendorff, L; Flyvbjerg, A; Frystyk, J; Jensen, L T; Rejnmark, L

    2013-04-01

    Pregnancy and lactation cause major changes in calcium homeostasis and bone metabolism. This population-based cohort study presents the physiological changes in biochemical indices of calcium homeostasis and bone metabolism during pregnancy and lactation We describe physiological changes in calcium homeostasis, calcitropic hormones and bone metabolism during pregnancy and lactation. We studied 153 women planning pregnancy (n=92 conceived) and 52 non-pregnant, age-matched female controls. Samples were collected prior to pregnancy, once each trimester and 2, 16 and 36 weeks postpartum. The controls were followed in parallel. P-estradiol (E2), prolactin and 1,25-dihydroxyvitamin D (1,25(OH)2D) increased (phormone (P-PTH) and calcitonin decreased (pgrowth factor I (IGF-I) was suppressed (pbone resorption and formation rose and fall, respectively (pbone formation markers increased in association with IGF-I changes (pbone turnover markers were associated with lactation status (pbone markers indicated a negative bone balance. The rise in bone formation in late pregnancy may be initiated by a spike in IGF-I levels. The high bone turnover in lactating women may be related to high prolactin and PTH levels, low E2 levels and perhaps increased parathyroid hormone-related protein levels.

  14. Neuronal Activity Drives Localized Blood-Brain-Barrier Transport of Serum Insulin-like Growth Factor-I into the CNS

    OpenAIRE

    Nishijima, T.; Piriz, Joaquin; Duflot, Sylvie; Fernández García, Ana María; Gaitán, Gema; Gómez-Pinedo, Ulises; García-Verdugo, José M.; Leroy, Félix; Soya, Hideaki; Núñez Molina, Ángel; Torres Alemán, Ignacio

    2010-01-01

    Upon entry into the central nervous system (CNS), serum insulin-like growth factor-1 (IGF-I) modulates neuronal growth, survival, and excitability. Yet mechanisms that trigger IGF-I entry across the blood-brain barrier remain unclear. We show that neuronal activity elicited by electrical, sensory, or behavioral stimulation increases IGF-I input in activated regions. Entrance of serum IGF-I is triggered by diffusible messengers (i.e., ATP, arachidonic acid derivatives) released during neurovas...

  15. Host factor I, Hfq, binds to Escherichia coli ompA mRNA in a growth rate-dependent fashion and regulates its stability

    DEFF Research Database (Denmark)

    Vytvytska, O; Jakobsen, J S; Balcunaite, G

    1998-01-01

    ompA was purified and identified as Hfq, a host factor initially recognized for its function in phage Qbeta replication. The ompA RNA-binding activity parallels the amount of Hfq, which is elevated in bacteria cultured at slow growth rate, a condition leading to facilitated degradation of the ompA m...... suggest a regulatory role for Hfq that specifically facilitates the ompA mRNA degradation in a growth rate-dependent manner....

  16. A longitudinal study of intrauterine growth and the placental growth hormone (GH)-insulin-like growth factor I axis in maternal circulation: association between placental GH and fetal growth

    DEFF Research Database (Denmark)

    Chellakooty, Marla; Vangsgaard, K; Larsen, T

    2004-01-01

    The aim of the study was 1) to evaluate the association of maternal serum levels of placental GH and IGF-I with fetal growth, and 2) to establish reference data for placental GH, IGF-I, and IGF-binding protein-3 (IGFBP-3) in normal pregnancies based on longitudinal measurements. A prospective...... above -2 SD. Placental GH levels were detectable in all samples from as early as 5 wk gestation and increased significantly throughout pregnancy to approximately 37 wk when peak levels of 22 ng/ml (range, 4.64-69.22 ng/ml) were reached. Subsequently, placental GH levels decreased until birth. The change...... in placental GH during 24.5-37.5 wk gestation was positively associated with fetal growth rate (P = 0.027) and birth weight (P = 0.027). Gestational age at peak placental GH values (P = 0.007) was associated with pregnancy length. A positive association between the change in placental GH and the change in IGF...

  17. A longitudinal study of intrauterine growth and the placental growth hormone (GH)-insulin-like growth factor I axis in maternal circulation: association between placental GH and fetal growth

    DEFF Research Database (Denmark)

    Chellakooty, Marla; Vangsgaard, K; Larsen, T

    2004-01-01

    The aim of the study was 1) to evaluate the association of maternal serum levels of placental GH and IGF-I with fetal growth, and 2) to establish reference data for placental GH, IGF-I, and IGF-binding protein-3 (IGFBP-3) in normal pregnancies based on longitudinal measurements. A prospective...... longitudinal study of 89 normal pregnant women was conducted. The women had, on the average, seven blood samples taken and three ultrasound examinations performed. All had normal umbilical artery pulsatility indexes during pregnancy and gave birth to singletons between 37 and 42 wk gestation with birth weights...... above -2 SD. Placental GH levels were detectable in all samples from as early as 5 wk gestation and increased significantly throughout pregnancy to approximately 37 wk when peak levels of 22 ng/ml (range, 4.64-69.22 ng/ml) were reached. Subsequently, placental GH levels decreased until birth. The change...

  18. Prediagnostic circulating concentrations of plasma insulin-like growth factor-I and risk of lymphoma in the European Prospective Investigation into Cancer and Nutrition

    NARCIS (Netherlands)

    Perez-Cornago, Aurora; Appleby, Paul N.; Tipper, Sarah; Key, Timothy J.; Allen, Naomi E.; Nieters, Alexandra; Vermeulen, Roel; Roulland, Sandrine; Casabonne, Delphine; Kaaks, Rudolf; Fortner, Renee T.; Boeing, Heiner; Trichopoulou, Antonia; La Vecchia, Carlo; Klinaki, Eleni; Hansen, Louise; Tjønneland, Anne; Bonnet, Fabrice; Fagherazzi, Guy; Boutron-Ruault, Marie Christine; Pala, Valeria; Masala, Giovanna; Sacerdote, Carlotta; Peeters, Petra H.; Bueno-de-Mesquita, H. Bas; Weiderpass, Elisabete; Dorronsoro, Miren; Quirós, J. Ramón; Barricarte, Aurelio; Gavrila, Diana; Agudo, Antonio; Borgquist, Signe; Rosendahl, Ann H.; Melin, Beatrice; Wareham, Nick; Khaw, Kay Tee; Gunter, Marc; Riboli, Elio; Vineis, Paolo; Travis, Ruth C.

    2017-01-01

    Insulin-like growth factor (IGF)-I has cancer promoting activities. However, the hypothesis that circulating IGF-I concentration is related to risk of lymphoma overall or its subtypes has not been examined prospectively. IGF-I concentration was measured in pre-diagnostic plasma samples from a nested

  19. Growth hormone-insulin-like growth factor-I axis in adult insulin-dependent diabetic patients: evidence for central hypersensitivity to growth hormone-releasing hormone and peripheral resistance to growth hormone.

    Science.gov (United States)

    Fainstein Day, P; Fagin, J A; Vaglio, R M; Litwak, L E; Picasso, M F; Gutman, R A

    1998-12-01

    The aim of this study was to assess the GH-IGFI axis, GH receptor availability, as reflected by the levels of GH-BP, and the amount of GH-dependent IGFBP-3 in adult IDDM patients with different degrees of metabolic control. Thus, 10 adult well-controlled IDDMs (HbA1 7.8 +/- 0.4%), 10 adult non-ketotic poorly controlled IDDMs (HbA1 13.3 +/- 7%) and 14 sex- and age-matched healthy controls were subjected to two intravenous GH-RH stimulation tests with 0.1 and 1.0 microg/kg body weight respectively, and a plasma IGF-1 generation test induced by the administration of hGH. Poorly controlled IDDM patients exhibited an exaggerated GH response to 1.0 microg/kg of GH-RH when compared to healthy control subjects. Low fasting plasma IGF-1 levels and a blunted IGF-1 response to exogenously administered hGH were also found in poorly controlled IDDMs when compared to the healthy control group. GH-BP levels were significantly lower in IDDMs than in normal controls, and correlated positively with the IGF-1 generation capacity after hGH. Serum IGFBP-3 levels measured by RIA were similar in IDDM and control groups. Good glycemic control for 5.7 +/- 0.9 months did not correct the above mentioned abnormalities of the GH-IGF-1 axis. Our findings suggest that IDDM is associated with a diminished availability of GH receptors and synthesis of IGF-1. GH might then increase as a compensatory mechanism, further down-regulating liver GH receptors, and thus perpetuating the initial abnormality.

  20. Induction of apoptosis by a peptide from Porphyra yezoensis: regulation of the insulin-like growth factor I receptor signaling pathway in MCF-7 cells.

    Science.gov (United States)

    Park, Su-Jin; Ryu, Jina; Kim, In-Hye; Choi, Youn-Hee; Nam, Taek-Jeong

    2014-09-01

    This study examined how PPY, a peptide from Porphyra yezoensis, regulates multiple cell growth-related signaling pathways in MCF-7 cells. This study determined that PPY induces cell cycle arrest and inhibits the IGF-IR signaling pathway. Cell proliferation studies revealed that PPY induced cell death in a dose-dependent manner. Expression levels of IGF-IR were decreased in MCF-7 cells by PPY in a dose‑dependent manner. These results indicate that inhibition of the IGF-IR pathway is also involved in PPY induced proliferation of MCF-7 cells. In addition, these data demonstrated that PPY induces cell cycle arrest and activates apoptosis.

  1. A peptide from Porphyra yezoensis stimulates the proliferation of IEC-6 cells by activating the insulin-like growth factor I receptor signaling pathway.

    Science.gov (United States)

    Lee, Min-Kyeong; Kim, In-Hye; Choi, Youn-Hee; Nam, Taek-Jeong

    2015-02-01

    Porphyra yezoensis (P. yezoensis) is the most noteworthy red alga and is mainly consumed in China, Japan and Korea. In the present study, the effects of a P. yezoensis peptide (PY‑PE) on cell proliferation and the associated signaling pathways were examined in IEC‑6 rat intestinal epithelial cells. First, the MTS assay showed that PY‑PE induced cell proliferation in a dose‑dependent manner. Subsequently, the mechanism behind the proliferative activity induced by PY‑PE was determined. The insulin‑like growth factor‑I receptor (IGF‑IR) signaling pathway was the main focus as it plays an important role in the regulation of cell growth and proliferation. PY‑PE increased the protein and mRNA expression of IGF‑IR, insulin receptor substrate‑1, Shc and PY‑99. In addition, PY‑PE stimulated extracellular signal‑regulated kinase phosphorylation and phosphatidylinositol 3‑kinase/Akt activation but inhibited p38 and c‑Jun N‑terminal kinase phosphorylation. Furthermore, PY‑PE treatment increased protein and mRNA expression levels of activator protein‑1, which regulates cell proliferation and survival, in the nuclear fraction. These results have significant implications for understanding the role of cell proliferation signaling pathways in intestinal epithelial cells.

  2. Influence of ad libitum milk replacer feeding and butyrate supplementation on the systemic and hepatic insulin-like growth factor I and its binding proteins in Holstein calves.

    Science.gov (United States)

    Frieten, D; Gerbert, C; Koch, C; Dusel, G; Eder, K; Hoeflich, A; Mielenz, B; Hammon, H M

    2018-02-01

    Ad libitum milk feeding and butyrate (B) supplementation have the potential to stimulate postnatal growth and development in calves. The somatotropic axis is the main endocrine regulator of postnatal growth and may be affected by both ad libitum milk replacer (MR) feeding and B supplementation in calves. We hypothesized that ad libitum MR feeding and B supplementation stimulate systemic and hepatic insulin-like growth factor (IGF)-I and IGF binding proteins (IGFBP) in preweaning calves. Sixty-four (32 male, 32 female) Holstein calves were examined from birth until wk 11 of life. Calves received MR either ad libitum (Adl) or restrictively (6 L/d; Res). In each feeding group half of the calves received a MR with 0.24% butyrate and the other half received same MR without butyrate. Ad libitum MR feeding was performed from d 4 until wk 8 of age. From wk 9 to 10, Adl and Res calves were gradually weaned and were fed 2 L/d until the end of the trial. Concentrate, hay, and water were freely available. Feed intake was measured daily and body weight weekly. Blood samples for analyzing plasma concentrations of glucose, insulin, IGF-I, and IGFBP-2, -3, and -4 were taken on d 1, 2, 4, and 7, then weekly or every other week (IGFBP) until wk 11 of life. Liver samples were taken on d 50 and at the end of the study (d 80) to measure gene expression of the growth hormone receptor 1A (GHR1A), IGF1, IGFBP1 to 4, and of the IGF Type 1 and insulin receptor in the liver. Intake of MR and body weight were greater, but concentrate intake was lower in Adl than in Res. Plasma concentrations of IGF-I and IGFBP-3 were greater and plasma concentration of IGFBP-2 was lower in Adl than in Res during the ad libitum milk feeding period. After reduction of MR in both groups to 2 L/d plasma concentrations of IGF-I and IGFBP-4 were lower and plasma concentration of IGFBP-2 was higher in Adl than in Res. Supplementation of B depressed plasma IGF-I from wk 1 to 4 and in wk 9. On d 50, mRNA abundance of

  3. Transforming growth factor-beta1 stimulates the production of insulin-like growth factor-I and insulin-like growth factor-binding protein-3 in human bone marrow stromal osteoblast progenitors

    DEFF Research Database (Denmark)

    Kveiborg, Marie; Flyvbjerg, Allan; Eriksen, E F

    2001-01-01

    While transforming growth factor-beta1 (TGF-beta1) regulates proliferation and differentiation of human osteoblast precursor cells, the mechanisms underlying these effects are not known. Several hormones and locally acting growth factors regulate osteoblast functions through changes in the insuli...

  4. Insulin-Like Growth Factor-I Induces Arginase Activity in Leishmania amazonensis Amastigote-Infected Macrophages through a Cytokine-Independent Mechanism

    Directory of Open Access Journals (Sweden)

    Celia Maria Vieira Vendrame

    2014-01-01

    Full Text Available Leishmania (Leishmania amazonensis exhibits peculiarities in its interactions with hosts. Because amastigotes are the primary form associated with the progression of infection, we studied the effect of insulin-like growth factor (IGF-I on interactions between L. (L. amazonensis amastigotes and macrophages. Upon stimulation of infected macrophages with IGF-I, we observed decreased nitric oxide production but increased arginase expression and activity, which lead to increased parasitism. However, stimulation of amastigote-infected macrophages with IGF-I did not result in altered cytokine levels compared to unstimulated controls. Because IGF-I is present in tissue fluids and also within macrophages, we examined the possible effect of this factor on phosphatidylserine (PS exposure on amastigotes, seen previously in tissue-derived amastigotes leading to increased parasitism. Stimulation with IGF-I induced PS exposure on amastigotes but not on promastigotes. Using a PS-liposome instead of amastigotes, we observed that the PS-liposome but not the control phosphatidylcholine-liposome led to increased arginase activity in macrophages, and this process was not blocked by anti-TGF-β antibodies. Our results suggest that in L. (L. amazonensis amastigote-infected macrophages, IGF-I induces arginase activity directly in amastigotes and in macrophages through the induction of PS exposure on amastigotes in the latter, which could lead to the alternative activation of macrophages through cytokine-independent mechanisms.

  5. Significance of determination of female sex hormones (E2, LH, FSH), insulin-like growth factor I (IGF-I) and leptin in girls with precocious puberty

    International Nuclear Information System (INIS)

    Huang Jianrong

    2004-01-01

    Objective: To investigate the diagnostic value of determination of serum levels of estradiol (E 2 ), luteinizing hormone (LH) and follicle stimulating hormone (FSH), insulin-like growth factor (IGF-I) and leptin in girls with idiopathic central precocious puberty (ICPP). Methods: Serum E 2 , LH, FSH, IGF-I (with chemiluminescence immunoassay) and leptin (with RIA) levels were determined in 35 girls with early development of breast as the sign of precocious puberty, of which, 15 was considered to be of the ICPP group and 20 of simple premature thelarche group (SPT). Criteria of diagnosis for ICPP were: peak LH value>12IU/L and LH/FSH>1 after GnRH stimulating test. Results: Serum E 2 , LH, FSH, IGF-I leptin levels in girls with ICPP were significantly higher than those in the girls with SPT (P 0.2 as the cut-off value for diagnosis of ICPP there would still be a positive rate of 86.6% suggesting that the diagnostic criteria might be set lower. Serum IGF-I levels were positively correlated to those of E 2 (r=0.47, P 2 and IGF-I. Conclusion: Determinations of serum E 2 , LH, FHS, IGF-I and leptin levels were helpful for the early diagnosis of ICPP. (author)

  6. Transforming growth factor-beta1 stimulates the production of insulin-like growth factor-I and insulin-like growth factor-binding protein-3 in human bone marrow stromal osteoblast progenitors

    DEFF Research Database (Denmark)

    Kveiborg, Marie; Flyvbjerg, Allan; Eriksen, E F

    2001-01-01

    While transforming growth factor-beta1 (TGF-beta1) regulates proliferation and differentiation of human osteoblast precursor cells, the mechanisms underlying these effects are not known. Several hormones and locally acting growth factors regulate osteoblast functions through changes in the insulin......-like growth factors (IGFs) and IGF-binding proteins (IGFBPs). Thus, we studied the effects of TGF-beta1 on IGFs and IGFBPs in human marrow stromal (hMS) osteoblast precursor cells. TGF-beta1 increased the steady-state mRNA level of IGF-I up to 8.5+/-0.6-fold (P...

  7. Circadian variation in biochemical markers of bone cell activity and insulin-like growth factor-I in two-year-old horses.

    Science.gov (United States)

    Jackson, B F; Blumsohn, A; Goodship, A E; Wilson, A M; Price, J S

    2003-11-01

    whether these markers develop a circadian rhythm at a later age when growth is complete. In the meantime, consistency in time of sampling should continue to be considered best practice when measuring biochemical markers of bone turnover in the horse.

  8. Decreased 11β-Hydroxysteroid Dehydrogenase 1 Level and Activity in Murine Pancreatic Islets Caused by Insulin-Like Growth Factor I Overexpression.

    Directory of Open Access Journals (Sweden)

    Subrata Chowdhury

    Full Text Available We have reported a high expression of IGF-I in pancreatic islet β-cells of transgenic mice under the metallothionein promoter. cDNA microarray analysis of the islets revealed that the expression of 82 genes was significantly altered compared to wild-type mice. Of these, 11β-hydroxysteroid dehydrogenase 1 (11β-HSD1, which is responsible for the conversion of inert cortisone (11-dehydrocorticosterone, DHC in rodents to active cortisol (corticosterone in the liver and adipose tissues, has not been identified previously as an IGF-I target in pancreatic islets. We characterized the changes in its protein level, enzyme activity and glucose-stimulated insulin secretion. In freshly isolated islets, the level of 11β-HSD1 protein was significantly lower in MT-IGF mice. Using dual-labeled immunofluorescence, 11β-HSD1 was observed exclusively in glucagon-producing, islet α-cells but at a lower level in transgenic vs. wild-type animals. MT-IGF islets also exhibited reduced enzymatic activities. Dexamethasone (DEX and DHC inhibited glucose-stimulated insulin secretion from freshly isolated islets of wild-type mice. In the islets of MT-IGF mice, 48-h pre-incubation of DEX caused a significant decrease in insulin release, while the effect of DHC was largely blunted consistent with diminished 11β-HSD1 activity. In order to establish the function of intracrine glucocorticoids, we overexpressed 11β-HSD1 cDNA in MIN6 insulinoma cells, which together with DHC caused apoptosis and a significant decrease in proliferation. Both effects were abolished with the treatment of an 11β-HSD1 inhibitor. Our results demonstrate an inhibitory effect of IGF-I on 11β-HSD1 expression and activity within the pancreatic islets, which may mediate part of the IGF-I effects on cell proliferation, survival and insulin secretion.

  9. Preparation of cultured skin for transplantation using insulin-like growth factor I in conjunction with insulin-like growth factor binding protein 5, epidermal growth factor, and vitronectin.

    Science.gov (United States)

    Dawson, Rebecca A; Upton, Zee; Malda, Jos; Harkin, Damien G

    2006-06-27

    Cultured skin for transplantation is routinely prepared by growing patient keratinocytes in the presence of semidefined sources of growth factors including serum and feeder cells, but these materials require substantial risk remediation and can contribute to transplant rejection. We have therefore investigated the potential of a novel combination of recombinant and purified growth factors to replace serum and feeder cells in cultures of human keratinocytes suitable for clinical application. Our technique was investigated with respect to culture establishment, serial propagation, colony-forming efficiency, immunocytochemistry, epidermal reconstruction, and suitability to support transplantation by aerosolization. We demonstrate that insulin-like growth factor (IGF)-I--used in conjunction with epidermal growth factor (EGF), insulin-like growth factor binding protein (IGFBP)-5 and vitronectin--supports growth in the absence of serum. Moreover, a threefold greater number of cells are generated within 7 days compared to those grown under current best practice conditions using serum (P<0.05). The resulting test cultures are suitable for epidermal reconstruction and support the option for delivery in the form of an aerosolized cell suspension. Serial propagation, with the view to producing confluent sheets for extensive injuries, was achieved but with less consistency and this result correlated with a significant decline in colony-forming efficiency compared to controls. IGF-I used in conjunction with IGFBP-5, EGF, and vitronectin provides a superior alternative to serum for the rapid expansion and transplantation of cultured keratinocytes within the first week of treatment. Nevertheless, further optimization is required with respect to elimination of feeder cells and serial expansion of cultures for treatment of extensive injuries.

  10. Factor de crecimiento semejante a la insulina tipo I (IGF-I y cirrosis hepática Insulin-like growth factor I (IGF-I and liver cirrhosis

    Directory of Open Access Journals (Sweden)

    M. Conchillo

    2007-03-01

    mejoría del metabolismo energético por efecto del IGF-I. Se precisan ensayos clínicos adicionales para identificar la dosis adecuada de IGF-I, el tiempo y ritmo de administración y el subgrupo de pacientes cirróticos que obtendrán mayor beneficio de este tratamiento sustitutivo.Insulin-like growth factor I (IGF-I is a polypeptide hormone secreted by multiple tissues in response to growth hormone (GH. It is partly responsible for GH activity, and also has glucose-lowering and anabolizing effects. Ninety percent of circulating IGF-I originates in the liver and has autocrine, paracrine, and endocrine effects, the latter on multiple tissues. Liver cirrhosis results in a progressive decline of hepatic IGF-I output, and this factor may become undetectable in advanced disease. Some cirrhosis complications, mainly those nutritional and metabolic in nature (insuline resistance, malnutrition, osteopenia, hypogonadism, intestinal disorders, may be at least partly related to this IGF-I deficiency, since some IGF-I effects represent a reverse image of cirrhosis complications. Despite this, IGF-I replacement therapy has been never suggested for cirrhosis. A number of experimental studies in cirrhotic rats showed that therapy using low-dose recombinant IGF-I exerts two types of effect on experimental cirrhosis: a liver improvement driven by improved hepatocellular function, portal hypertension, and liver fibrosis; and b cirrhosis-related extrahepatic disorder improvement driven by improved food efficiency, muscle mass, bone mass, gonadal function and structure, and intestinal function and structure, with a normalization of sugar and amino acid malabsorption, and improved intstinal barrier function, manifested by reduced endotoxemia and bacterial translocation. Subsequently, the first randomized, double-blind, placebo-controlled, pilot clinical trial in a small number of cirrhotic patients showed increased serum albumin and improved energy metabolism as a result of IGF-I use

  11. Long-term insulin-like growth factor-I expression in skeletal muscles attenuates the enhanced in vitro proliferation ability of the resident satellite cells in transgenic mice

    Science.gov (United States)

    Chakravarthy, M. V.; Fiorotto, M. L.; Schwartz, R. J.; Booth, F. W.

    2001-01-01

    Insulin-like growth factor-I (IGF-I) overexpression for 1-month in mouse skeletal muscle increases satellite cell proliferation potential. However, it is unknown whether this beneficial enhancement by IGF-I expression would persist over a longer-term duration in aged mice. This is an important issue to address if a prolonged course of IGF-I is to be used clinically in muscle-wasting conditions where satellite cells may become limiting. Using the IGF-I transgenic (IGF-I Tg) mouse that selectively expresses the IGF-I transgene in striated muscles, we found that 18-months of continuous IGF-I overexpression led to a loss in the enhanced in vitro proliferative capacity of satellite cells from Tg skeletal muscles. Also 18-month-old IGF-I Tg satellite cells lost the enhanced BrdU incorporation, greater pRb and Akt phosphorylations, and decreased p27(Kip1) levels initially observed in cells from 1-month-old IGF-I Tg mice. The levels of those biochemical markers reverted to similar values seen in the 18-months WT littermates. These findings, therefore, suggest that there is no further beneficial effect on enhancing satellite cell proliferation ability with persistent long-term expression of IGF-I in skeletal muscles of these transgenic mice.

  12. Regulation of hypoxia-inducible factor-1α (HIF-1α expression by interleukin-1β (IL-1 β, insulin-like growth factors I (IGF-I and II (IGF-II in human osteoarthritic chondrocytes

    Directory of Open Access Journals (Sweden)

    Angelica Rossi Sartori-Cintra

    2012-01-01

    Full Text Available OBJECTIVE: Hypoxia-inducible factor 1 alpha regulates genes related to cellular survival under hypoxia. This factor is present in osteroarthritic chondrocytes, and cytokines, such as interleukin-1 beta, participate in the pathogenesis of osteoarthritis, thereby increasing the activities of proteolytic enzymes, such as matrix metalloproteinases, and accelerating cartilage destruction. We hypothesize that Hypoxia Inducible Factor-1 alpha (HIF-1α can regulate cytokines (catabolic action and/or growth factors (anabolic action in osteoarthritis. The purpose of this study was to investigate the modulation of HIF-1α in human osteoarthritic chondrocytes by interleukin-1 beta (IL-1β and insulin-like growth factors I (IGF-I and II (IGF-II and to determine the involvement of the phosphatidylinositol-3kinase (PI-3K pathway in this process. METHODS: Human osteroarthritic chondrocytes were stimulated with IL-1β, IGF-I and IGF-II and LY294002, a specific inhibitor of PI-3K. Nuclear protein levels and gene expression were analyzed by western blot and quantitative reverse transcription-polymerase chain reaction analyses, respectively. RESULTS: HIF-1α expression was upregulated by IL-1β at the protein level but not at the gene level. IGF-I treatment resulted in increases in both the protein and mRNA levels of HIF-1α , whereas IGF-II had no effect on its expression. However, all of these stimuli exploited the PI-3K pathway. CONCLUSION: IL-1β upregulated the levels of HIF-1α protein post-transcriptionally, whereas IGF-I increased HIF-1α at the transcript level. In contrast, IGF-II did not affect the protein or gene expression levels of HIF-1α . Furthermore, all of the tested stimuli exploited the PI-3K pathway to some degree. Based on these findings, we are able to suggest that Hypoxia inducible Factor-1 exhibits protective activity in chondrocytes during osteoarthritis.

  13. Normal growth spurt and final height despite low levels of all forms of circulating insulin-like growth factor-I in a patient with acid-labile subunit deficiency

    DEFF Research Database (Denmark)

    Domené, Horacio M; Martínez, Alicia S; Frystyk, Jan

    2007-01-01

    BACKGROUND: In a recently described patient with acid-labile subunit (ALS) deficiency, the inability to form ternary complexes resulted in a marked reduction in circulating total insulin-like growth factor (IGF)-I, whereas skeletal growth was only marginally affected. To further study the role...... of circulating versus locally produced IGF-I in skeletal growth in this patient, we now describe in detail growth changes and their relationship with several components of the circulating IGF system. DESIGN AND METHODS: We followed growth and development up to the final height in a patient with complete ALS...... and pubertal onset. Six months of GH treatment had no effect on growth. At the age of 19.3 years, he spontaneously completed puberty and had a normal growth spurt for a late adolescent (peak height velocity of 8.4 cm/year). A normal final height was attained at 21.3 years (167.5 cm; -0.78 SDS). During as well...

  14. Short-term effects of replacing milk with cola beverages on insulin-like growth factor-I and insulin-glucose metabolism: a 10 d interventional study in young men.

    Science.gov (United States)

    Hoppe, Camilla; Kristensen, Mette; Boiesen, Marlene; Kudsk, Jane; Fleischer Michaelsen, Kim; Mølgaard, Christian

    2009-10-01

    In the Western world, a trend towards increased consumption of carbonated soft drinks combined with a decreasing intake of milk is observed. This may affect circulating insulin-like growth factor I (IGF-I) and fasting insulin, as seen in pre-pubertal children. The present study was designed to reflect the trend of replacing milk with carbonated beverages in young men and to study the effects of this replacement on IGF-I, IGF-binding protein 3 (IGFBP-3), IGF-I:IGFBP-3 and glucose-insulin metabolism. A randomised, controlled crossover intervention study, in which eleven men aged 22-29 years were given a low-Ca diet in two 10 d periods with 10 d washout in between. In one period, they drank 2.5 litres of Coca Cola(R) per day and the other period 2.5 litres of semi-skimmed milk. Serum IGF-I, IGFBP-3 (RIA), insulin (fluoro immunoassay) and glucose (Cobas) were determined at baseline and end point of each intervention period. Insulin resistance and beta-cell function were calculated with the homeostasis model assessment. A decrease in serum IGF-I was observed in the cola period compared with the milk period (P cola over a 10 d period decreases total IGF-I compared with a high intake of milk, with no effect on glucose-insulin metabolism in adult men. It is unknown whether this is a transient phenomenon or whether it has long-term consequences.

  15. The growth hormone/insulin-like growth factor-I axis hormones and bone markers in elite athletes in response to a maximum exercise test

    DEFF Research Database (Denmark)

    Ehrnborg, C; Lange, K H W; Dall, R

    2003-01-01

    and bone markers at specific time points are presented. Most of the variables correlated negatively with age. In summary, the maximum exercise test showed a rather uniform pattern, with peak concentrations of the GH/IGF-I axis hormones and the bone markers ICTP and P-III-P immediately after exercise......The aim of the GH-2000 project is to develop a method for detecting GH doping among athletes. Previous papers in the GH-2000 project have proposed that a forthcoming method to detect GH doping will need specific components from the GH/IGF-I axis and bone markers because these specific variables......-53 yr) from Denmark, the United Kingdom, Italy, and Sweden participated in the study. The serum concentrations of total GH, GH22 kDa, IGF-I, IGF binding protein (IGFBP)-2, IGFBP-3, acid-labile subunit, procollagen type III (P-III-P), and the bone markers osteocalcin, carboxy-terminal cross...

  16. EXPRESSION OF GROWTH HORMONE (PhGH GENE AND ANALYSIS OF INSULINE-LIKE GROWTH FACTOR I (IGF-I PRODUCTION IN AFRICAN CATFISH (Clarias gariepinus TRANSGENIC F-1

    Directory of Open Access Journals (Sweden)

    Huria Marnis

    2013-12-01

    Full Text Available We have previously produced F-1 transgenic of African catfish from crosses between founder transgenic female and non transgenic male. The aim of this study was to evaluate distribution and expression PhGH growth hormone gene transgenic African catfish organs and to measure the concentration of IGF-I in plasma. Transgene was detected using the PCR method in various organs, namely pituitary, brain, liver, heart, spleen, kidney, intestine, stomach, muscle, gill, and eye. Transgene expression levels were analyzed using the method of quantitative Reverse Transcriptase-Polymerase Chain Reaction (qRT-PCR. Plasma samples were analyzed for Insuline-like Growth Factor (IGF-I using Enzyme Linked Immunosorbent Assay (ELISA method. The results showed that the PhGH was detected and expressed in all organs of the transgenic African catfish (F-1. Liver exhibited the highest level of PhGH mRNA (23 x 106 copies. The plasma IGF-I levels in transgenic individuals were not significant than non transgenic. The higher level of exogenous PhGH gene expression may not represent the production of IGF-1.

  17. Associations of serum insulin-like growth factor-I and insulin-like growth factor-binding protein 3 levels with biomarker-calibrated protein, dairy product and milk intake in the Women's Health Initiative.

    Science.gov (United States)

    Beasley, Jeannette M; Gunter, Marc J; LaCroix, Andrea Z; Prentice, Ross L; Neuhouser, Marian L; Tinker, Lesley F; Vitolins, Mara Z; Strickler, Howard D

    2014-03-14

    It is well established that protein-energy malnutrition decreases serum insulin-like growth factor (IGF)-I levels, and supplementation of 30 g of whey protein daily has been shown to increase serum IGF-I levels by 8 % after 2 years in a clinical trial. Cohort studies provide the opportunity to assess associations between dietary protein intake and IGF axis protein levels under more typical eating conditions. In the present study, we assessed the associations of circulating IGF axis protein levels (ELISA, Diagnostic Systems Laboratories) with total biomarker-calibrated protein intake, as well as with dairy product and milk intake, among postmenopausal women enrolled in the Women's Health Initiative (n 747). Analyses were carried out using multivariate linear regression models that adjusted for age, BMI, race/ethnicity, education, biomarker-calibrated energy intake, alcohol intake, smoking, physical activity and hormone therapy use. There was a positive association between milk intake and free IGF-I levels. A three-serving increase in milk intake per d (approximately 30 g of protein) was associated with an estimated average 18·6 % higher increase in free IGF-I levels (95 % CI 0·9, 39·3 %). However, total IGF-I and insulin-like growth factor-binding protein 3 (IGFBP-3) levels were not associated with milk consumption and nor were there associations between biomarker-calibrated protein intake, biomarker-calibrated energy intake, and free IGF-I, total IGF-I or IGFBP-3 levels. The findings of the present study carried out in postmenopausal women are consistent with clinical trial data suggesting a specific relationship between milk consumption and serum IGF-I levels, although in the present study this association was only statistically significant for free, but not total, IGF-I or IGFBP-3 levels.

  18. Germination, growth and physiological responses of Senegalia ...

    African Journals Online (AJOL)

    For plants growth and physiological responses, seedlings were individually cultivated in plastic bags (25×12 cm) containing non-sterile soil and watered with four salt solutions (0, 86, 171 and 257 mM NaCl). Four months after the plants' cultivation, the results showed that for all species, the salinity reduced significantly the ...

  19. Growth performance and immunological responses of broiler ...

    African Journals Online (AJOL)

    This study was conducted to determine the growth performance and immune response of broiler chickens fed synbiotic and diet acidifier to Newcastle disease vaccinations. One hundred and forty four (144) day old broiler chickens were randomly assigned to four dietary treatments replicated thrice with 12 birds per replicate ...

  20. Growth, haematological and biochemical responses of growing ...

    African Journals Online (AJOL)

    Growth, haematological and biochemical responses of growing lambs injected. A.N.M Nour El-Din, S.Z El-Zarkouny, S.Z El-Zarkouny, H Ghobashy, H Ghobashy, E.I Abdel-Gawad, E.I Abdel-Gawad, D.J Kesler, D.J Kesler ...

  1. Growth response of Oreochromis niloticus fingerlingsfed fermented ...

    African Journals Online (AJOL)

    The study was carried out to determine the growth response of Oreochromis niloticus fingerlings fed fermented Parkia biglobosa (locust beans) diets. P. biglobosa served as an attractant in these diets. Two hundred and twenty-five fingerlings (10.1±0.1 g/fish) mixed sex were treated with five diets containing maize, fishmeal, ...

  2. Circulating insulin-like growth factor-I, insulin-like growth factor binding protein-3 and terminal duct lobular unit involution of the breast: a cross-sectional study of women with benign breast disease.

    Science.gov (United States)

    Horne, Hisani N; Sherman, Mark E; Pfeiffer, Ruth M; Figueroa, Jonine D; Khodr, Zeina G; Falk, Roni T; Pollak, Michael; Patel, Deesha A; Palakal, Maya M; Linville, Laura; Papathomas, Daphne; Geller, Berta; Vacek, Pamela M; Weaver, Donald L; Chicoine, Rachael; Shepherd, John; Mahmoudzadeh, Amir Pasha; Wang, Jeff; Fan, Bo; Malkov, Serghei; Herschorn, Sally; Hewitt, Stephen M; Brinton, Louise A; Gierach, Gretchen L

    2016-02-18

    Terminal duct lobular units (TDLUs) are the primary structures from which breast cancers and their precursors arise. Decreased age-related TDLU involution and elevated mammographic density are both correlated and independently associated with increased breast cancer risk, suggesting that these characteristics of breast parenchyma might be linked to a common factor. Given data suggesting that increased circulating levels of insulin-like growth factors (IGFs) factors are related to reduced TDLU involution and increased mammographic density, we assessed these relationships using validated quantitative methods in a cross-sectional study of women with benign breast disease. Serum IGF-I, IGFBP-3 and IGF-I:IGFBP-3 molar ratios were measured in 228 women, ages 40-64, who underwent diagnostic breast biopsies yielding benign diagnoses at University of Vermont affiliated centers. Biopsies were assessed for three separate measures inversely related to TDLU involution: numbers of TDLUs per unit of tissue area ("TDLU count"), median TDLU diameter ("TDLU span"), and number of acini per TDLU ("acini count"). Regression models, stratified by menopausal status and adjusted for potential confounders, were used to assess the associations of TDLU count, median TDLU span and median acini count per TDLU with tertiles of circulating IGFs. Given that mammographic density is associated with both IGF levels and breast cancer risk, we also stratified these associations by mammographic density. Higher IGF-I levels among postmenopausal women and an elevated IGF-I:IGFBP-3 ratio among all women were associated with higher TDLU counts, a marker of decreased lobular involution (P-trend = 0.009 and women with elevated mammographic density (P-interaction women with high mammographic density and limited TDLU involution, two markers that have been related to increased breast cancer risk. If confirmed in prospective studies with cancer endpoints, these data may suggest that evaluation of IGF

  3. Growth hormone (GH) provocative retesting of 108 young adults with childhood-onset GH deficiency and the diagnostic value of insulin-like growth factor I (IGF-I) and IGF-binding protein-3

    DEFF Research Database (Denmark)

    Juul, A; Kastrup, K W; Pedersen, S A

    1997-01-01

    controversy still exists. In adults, the diagnostic value of IGF-I and IGFBP-3 suspected of GHD has been reported in only a few studies. We performed a GH provocative test, using oral clonidine, in 108 patients who had previously been treated with GH during childhood (73 men and 35 women). Basal IGF.......e. 45% of patients treated with GH during childhood because of isolated GHD had a normal GH response when retested in adulthood. Multiple regression analysis revealed that peak GH levels were dependent on the degree of hypopituitarism, body mass index, and duration of disease. IGF-I levels were below -2...... determinations predict the outcome of a GH provocative test in adults suspected of GHD and believe that IGF-I as well as IGFBP-3 serum concentrations are valuable diagnostic parameters in the evaluation of GHD in adults with childhood-onset disease. We suggest that children who have been treated with GH should...

  4. Microbial growth responses upon rewetting dry soil

    Science.gov (United States)

    Meisner, Annelein; Rousk, Johannes; Bååth, Erland

    2015-04-01

    Increased rainfall and drought periods are expected to occur with current climate change, leading to fluctuations in soil moisture. Changes in soil moisture are known to affect carbon cycling. A pulse of carbon dioxide release (respiration) is often observed after rewetting a dry soil and a drying threshold is observed before this pulse emerges. Increased microbial activity is often assumed to be the cause for the pulse in respiration. Yet, the microbial growth responses that underlie this pulse are often not studied. The following questions will be addressed in this presentation. 1) Do fungal and bacterial growth explain the pulse in respiration upon rewetting a dry soil? 2) How does microbial growth respond to different drying intensities before rewetting? To answer the research questions, soils from Sweden, U.K. and Greenland were put in microcosms, air-dried for four days, a prolonged period or to different moisture content before rewetting. We measured soil respiration, fungal growth rates and/or bacterial growth rates at high temporal resolution during one week after rewetting. Our results suggest that the respiration pulse upon rewetting dry soil is not due to high microbial growth rates. During the first hours after rewetting, bacterial and fungal growth rates were low whereas the respiration rates were high. As such, there was a decoupling between the pulse in respiration and microbial growth rates. Two patterns of bacterial growth were observed upon rewetting the three different soils. In "pattern 1", bacteria started growing immediately in a linear pattern up to values similar as the moist control. In "pattern 2", bacteria started growing exponentially after a lag period of no growth with a second pulse of respiration occurring at the start of bacterial growth. Manipulating the drying intensity changed the patterns. Soils with "pattern 1" were changed to "pattern 2" when subjected to more extensive drying periods whereas soils with "pattern 2" were

  5. A comparison of different definitions of growth response in short prepubertal children treated with growth hormone

    DEFF Research Database (Denmark)

    Bang, P; Bjerknes, R; Dahlgren, J

    2011-01-01

    How to define poor growth response in the management of short growth hormone (GH)-treated children is controversial. Aim: Assess various criteria of poor response.......How to define poor growth response in the management of short growth hormone (GH)-treated children is controversial. Aim: Assess various criteria of poor response....

  6. Comparison of response to 2-years' growth hormone treatment in children with isolated growth hormone deficiency, born small for gestational age, idiopathic short stature, or multiple pituitary hormone deficiency

    DEFF Research Database (Denmark)

    Lee, Peter A; Sävendahl, Lars; Oliver, Isabelle

    2012-01-01

    , collected from two large ongoing observational outcome studies, was to evaluate growth and insulin-like growth factor-I (IGF-I) response data for children of short stature with IGHD, MPHD, SGA, or ISS following two years of treatment with the recombinant GH product Norditropin® (Novo Nordisk A/S, Bagsværd......Few studies have compared the response to growth hormone (GH) treatment between indications such as isolated growth hormone deficiency (IGHD), born small for gestational age (SGA), idiopathic short stature (ISS), and multiple pituitary hormone deficiency (MPHD). The aim of this analysis of data...

  7. Report on responsible growth. AREVA in 2008

    International Nuclear Information System (INIS)

    2009-01-01

    All over the world, AREVA supplies its customers with solutions for carbon-free power generation and electricity transmission and distribution. With its knowledge and expertise in these fields, the group has a leading role to play in meeting the world's energy needs. Ranked first in the global nuclear power industry, AREVA's unique integrated offering covers every stage of the fuel cycle, reactor design and construction, and related services. In addition, the group is expanding its operations in renewable energies. AREVA is also a world leader in electricity transmission and distribution and offers its customers a complete range of solutions for greater grid stability and energy efficiency. Sustainable development is a core component of the group's industrial strategy. Its 75,000 employees work every day to make AREVA a responsible industrial player that is helping to supply ever cleaner, safer and more economical energy to the greatest number of people. Sustainable development is a keystone of AREVA's industrial strategy for achieving growth that is profitable, socially responsible and respectful of the environment. To translate this choice into reality, AREVA integrates sustainable development into its management practices via a continuous improvement initiative revolving around ten commitments: customer satisfaction, financial performance, governance, community involvement, environmental protection, innovation, continuous improvement, commitment to employees, risk management and prevention, dialogue and consensus building. This document is Areva's 2008 report on responsible growth. After the Messages from the Chairman of the Supervisory Board and from the Chief Executive Officer, the report presents the Key data and Highlights of the period, the Corporate governance, the Organization of the group, the Share information and shareholder relations, the uranium reserves, the growing energy demand and the World's population demographic growth, Areva's actions to

  8. Acute somatomedin response to growth hormone: radioreceptor assay versus radioimmunoassay

    International Nuclear Information System (INIS)

    Kemp, S.F.; Rosenfeld, R.G.; Liu, F.; Gaspich, S.; Hintz, R.L.

    1981-01-01

    The acute somatomedin (SM) response to GH therapy has been examined in 21 GH-deficient children using a placental membrane radioreceptor assay (RRA) which measures a variety of SMs and a RIA specific for SM-C and insulin-like growth factor I (IGF-I). Plasma for determination of SM peptide content was obtained before initiation of therapy and 13 h after each of four daily injections of GH (0.1 U/kg). An additional SM determination was performed after 6 weeks of GH therapy (0.1 U/kg, three times per week) in seven of the subjects. RRA and RIA SM determiations were performed on the same acid-chromatographed sample and were compared to an acid chromatographed pooled plasma standard. The 4 days of GH therapy resulted in an increase in SM levels from 0.39+/- 0.24 to 1.18 +/- 0.62 (+/- SD) U/ml, determined by RIA. A single injection of GH resulted in a significant rise in plasma SM levels, measured by either RRA or RIA (P less than 0.001). Subjects who responded poorly to two injections of GH also had low SM levels after 4 days and even after 6 weeks of GH therapy. The RRA resulted in consistently higher value than the RIA. This difference was even greater when results were compared to a pure IGF-I/SM-C standard. The SM peptide contents determined by RRA and RIA were strongly correlated, not only for the group, but also among the determinations for each individual subject. However, the consistently higher values observed when the SM peptide content was measured by RRA compared to that measured by RIA and the variability in the RRA to RIA ratio among individual subjects suggest that the IGFI/SM-C RIA measures only one of a number of GH-dependent SM peptides

  9. Sugarbeet leaf growth and yield response to soil water deficit ...

    African Journals Online (AJOL)

    18 oct. 1999 ... This study evaluated the responses of sugarbeet leaf growth, sugar yield and yield components to soil water deficit imposed at various periods during growth in a glasshouse. Leaf growth showed high sensitivity to soil water deficit and responses varied with periods at which the deficit occurred. Water deficit ...

  10. 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.

  11. 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

  12. Serum concentrations of free and total insulin-like growth factor-I, IGF binding proteins -1 and -3 and IGFBP-3 protease activity in boys with normal or precocious puberty

    DEFF Research Database (Denmark)

    Juul, A; Flyvbjerg, Allan; Frystyk, Jan

    1996-01-01

    Circulating IGF-I and IGF binding protein-3 (IGFBP-3) levels both increase in puberty where growth velocity is high. The amount of free IGF-I is dependent on the IGF-I level and on the concentrations of the specific IGFBPs. Furthermore, IGFBP-3 proteolysis regulates the bioavailability of IGF......-I. However, the concentration of free IGF-I and possible IGFBP-3 proteolytic activity in puberty has not previously been studied....

  13. Influence of Insulin-Like Growth Factor-I on Maturation and Fertilization Rate of Immature Oocyte and Embryo Development in NMRI Mouse with TCM199 and α-MEM Medium.

    Science.gov (United States)

    Toori, Mehdi Akbartabar; Mosavi, Esmaeil; Nikseresht, Mohsen; Barmak, Mehrzad Jafari; Mahmoudi, Reza

    2014-12-01

    In vitro maturation (IVM) of oocytes and subsequent, in vitro fertilization (IVF) for the generation of embryos in the laboratory has important values. Growth factors are a component of a complex system of autocrine and paracrine factors that have a regulatory role in ovarian function and affect oocyte maturation. Therefore, the aim of this study is to evaluate the effect of IGF-I on IVM and IVF of mice oocytes during culture with α-MEM and TCM199 medium. Cumulus oocyte complexes (COCs) and denuded oocyte were obtained from 4-6 week old NMRI mice and underwent in vitro maturation and in vitro fertilization in presence or absence of IGF-I with α-MEM and TCM199. Maturation rate (79.6%), fertilization rate (87.2%), two cells development rate (79.5%) and blastocyst rate(43.2%) was higher in COCs cultured in α-MEM with IGF-I, while lower maturation rate (50.6%) fertilization rate (61%), two cells development rate (48.8%) and blastocyst rate(14.6%) were seen in cultured denuded oocytes (DOs) in TCM199 without growth factor. As well as, maturation fertilization, two cells development and blastocyst rates in COCs were higher than DOs. Our findings have shown that IGF-I is involved in the oocyte biology and improve the oocyte maturation, fertilization and embryo development to blastocyst competence in vitro. In addition, it has also shown that cumulus cells are vital for oocyte development when IGF-1 added to the mediums.

  14. 20 kDa human growth hormone (20K hGH) stimulates insulin-like growth factor-I (IGF-I) gene expression at lower concentrations than 22K hGH in hGH receptor-expressing Ba/F3 cells.

    Science.gov (United States)

    Yoshizato, H; Tanaka, M; Fujikawa, T; Higashimoto, Y; Shimizu, A; Nakashima, K

    2000-03-01

    Growth hormone (GH) secreted from the pituitary is essential for postnatal growth in animals. GH exerts its actions by a direct effect on target organs and by stimulating insulin-like growth factor I (IGF-I) production. In the human pituitary, there is a naturally occurring variant protein which has a molecular mass of 20 kDa (20K hGH) besides the major 22 kDa hGH (22K hGH), but the physiological actions of 20K hGH are still poorly understood. In this study we have examined its effects on the IGF-I mRNA expression in the pro B-cell line Ba/F3 cells stably expressing hGH receptor (Ba/F3-hGHR). Ba/F3-hGHR cells were incubated for 2 h with a series of various concentrations (10 pM to approximately 10 nM) of 20K or 22K hGH. The IGF-I mRNA expression in the Ba/F3-hGHR cells was detected by the RT-PCR method. IGF-I gene expression was increased by 20K and 22K hGH stimulation, but not by PRL or IL-3 in the Ba/F3-hGHR. And this effect was not observed in parental Ba/F3 cells. Lower concentrations of 20K hGH more strongly induced IGF-I gene expression than 22K-hGH. These results suggest that 20K and 22K hGH stimulate the IGF-I gene expression in the Ba/F3-hGHR through hGH receptors, and that the stronger effect of 20K hGH than that of 22K hGH in enhancing the IGF-I gene expression may be correlated with a 20K hGH specific receptor dimerization mechanism.

  15. Targeting 3-phosphoinoside-dependent kinase-1 to inhibit insulin-like growth factor-I induced AKT and p70 S6 kinase activation in breast cancer cells.

    Directory of Open Access Journals (Sweden)

    Sangita M Baxi

    Full Text Available Binding of IGF to IGF-IR activates PI3K to generate PIP3 which in turn recruits and activates proteins that contain a pleckstrin homology (PH domain, including AKT and PDK1. PDK1 is highly expressed in breast tumor samples and breast cancer cell lines. Here we demonstrate that targeting PDK1 with the potent and selective PDK1 inhibitor PF-5177624 in the IGF-PI3K pathway blocks breast cancer cell proliferation and transformation. Breast cancer cell lines MCF7 and T47D, representing the luminal ER positive subtype and harboring PIK3CA mutations, were most responsive to IGF-I induction resulting in upregulated AKT and p70S6K phosphorylation via PDK1 activation. PF-5177624 downregulated AKT and p70S6K phosphorylation, blocked cell cycle progression, and decreased cell proliferation and transformation to block IGFR-I induced activation in breast cancer cells. These results may provide insight into clinical strategies for developing an IGFR-I inhibitor and/or a PDK1 inhibitor in luminal breast cancer patients.

  16. Plant growth responses to polypropylene--biocontainers

    Science.gov (United States)

    The influence of bio-fillers incorporated into polypropylene (PP) on the growth of plants was evaluated. Biocontainers were created by injection molding of PP with 25-40% by weight of Osage orange tree, Paulownia tree, coffee tree wood or dried distillers grain and 5% by weight of maleated polypropy...

  17. Growth response and survival of Heterobranchus longifilis ...

    African Journals Online (AJOL)

    In an effort to utilize feed efficiently, promote growth, increase survival and reduce labour costs associated with feeding, Heterobranchus longifilis ingerlings were placed on one of four feeding frequencies; once/day, twice/day; once every other day, and twice every other day for 56 days. They were fed with a commercial ...

  18. Growth response and survival of Heterobranchus longifilis ...

    African Journals Online (AJOL)

    GRACE

    2006-05-02

    May 2, 2006 ... quadratic regression analysis observed that rainbow trout. Oncorhynchus mykiss had higher growth rates when fed. 3 times/day compared to fish fed once/day or twice/day, but were not different from fish fed four times/day. The results of this study of fish fed twice daily also agree with those of Noeske-Hallin ...

  19. Growth and physiological responses to water and nutrient stress in ...

    African Journals Online (AJOL)

    The research was conducted to detect changes in growth, physiology and nutrient concentration in response to two watering regimes (well-watered and water-stress conditions) and to two nutrient regimes (with or without fertilization) of oil palm. Under stress conditions, changes in plant growth, dry matter allocation, relative ...

  20. Growth, haematological and biochemical responses of growing ...

    African Journals Online (AJOL)

    p2492989

    Abstract. Physiological and productive responses to recombinant bovine somatotropin (rbST) injection and calcium soap of fatty acids (CSFA) supplementation were studied in post-weaning male Rahmani lambs. Male lambs (n = 20) of similar initial body weight (27.9 kg) and age (162 d) were divided randomly into four.

  1. Improved growth response to GH treatment in irradiated children

    International Nuclear Information System (INIS)

    Lannering, B.; Albertsson-Wikland, K.

    1989-01-01

    The growth response to two years of GH treatment was studied in fifteen children after radiotherapy for a cranial tumour. The growth response was compared to that of short children (-2 SD) and that of children with idiopathic growth hormone deficiency (GHD) of similar ages. All children were treated with hGH 0.1 IU/kg/day s.c.; which is a higher dose and frequency than previously reported for irradiated children. On this protocol the growth rate increased 5.0 +- 0.5 cm/y (mean +- SEM) the first year and 3.8 +- 0.7 cm/y the second year compared to the growth rate the year before GH-treatment. Although the net gain in growth was higher than previously reported, the first year growth response was significantly reduced (p less than 0.05) compared to that of GHD-children (7.6 +- 0.5 cm/y) but exceeded (p less than 0.05) that of short children (3.4 +- 0.3 cm/y). The median spontaneous 24 h-GH secretion was 209 mU/l in the short children, 52 mU/l in the irradiated children and 16 mU/l in the idiopathic GHD children. Thus the growth increment varied inversely to the spontaneous GH secretion observed in the three groups

  2. Early growth and postprandial appetite regulatory hormone responses

    DEFF Research Database (Denmark)

    Perälä, Mia-Maria; Kajantie, Eero; Valsta, Liisa M

    2013-01-01

    Strong epidemiological evidence suggests that slow prenatal or postnatal growth is associated with an increased risk of CVD and other metabolic diseases. However, little is known whether early growth affects postprandial metabolism and, especially, the appetite regulatory hormone system. Therefore......, we investigated the impact of early growth on postprandial appetite regulatory hormone responses to two high-protein and two high-fat content meals. Healthy, 65-75-year-old volunteers from the Helsinki Birth Cohort Study were recruited; twelve with a slow increase in BMI during the first year of life......, early growth may have a role in programming appetite regulatory hormone secretion in later life. Slow early growth is also associated with higher postprandial insulin and TAG responses but not with incretin levels....

  3. Growth and yield responses of cowpea genotypes to soluble and ...

    African Journals Online (AJOL)

    Growth and yield responses of cowpea genotypes to soluble and rock P fertilizers on acid, highly weathered soil from humid tropical .... their response with respect to soluble P and to rock P fertilizers. MATERIALS AND METHODS ..... variable charge like iron and aluminum oxides. (Quang et al., 1996). The very low organic.

  4. Growth Response of Silver Fir and Bosnian Pine from Kosovo

    OpenAIRE

    Elvin Toromani; Faruk Bojaxhi

    2010-01-01

    Background and Purpose: This paper explore the growth-climate relationships in total ring width chronologies of silver fir (Abies alba Mill.) and Bosnian pine (Pinus heldreichii Christ). The objective of this study is to quantify the climate influence on radial growth of both species. The relationships between climate and ring widths were analyzed using extreme growing years (called pointer years), simple correlations and response functions analysis (bootstrapped coefficients). The objectives...

  5. Analysis of Network Topologies Underlying Ethylene Growth Response Kinetics.

    Science.gov (United States)

    Prescott, Aaron M; McCollough, Forest W; Eldreth, Bryan L; Binder, Brad M; Abel, Steven M

    2016-01-01

    Most models for ethylene signaling involve a linear pathway. However, measurements of seedling growth kinetics when ethylene is applied and removed have resulted in more complex network models that include coherent feedforward, negative feedback, and positive feedback motifs. The dynamical responses of the proposed networks have not been explored in a quantitative manner. Here, we explore (i) whether any of the proposed models are capable of producing growth-response behaviors consistent with experimental observations and (ii) what mechanistic roles various parts of the network topologies play in ethylene signaling. To address this, we used computational methods to explore two general network topologies: The first contains a coherent feedforward loop that inhibits growth and a negative feedback from growth onto itself (CFF/NFB). In the second, ethylene promotes the cleavage of EIN2, with the product of the cleavage inhibiting growth and promoting the production of EIN2 through a positive feedback loop (PFB). Since few network parameters for ethylene signaling are known in detail, we used an evolutionary algorithm to explore sets of parameters that produce behaviors similar to experimental growth response kinetics of both wildtype and mutant seedlings. We generated a library of parameter sets by independently running the evolutionary algorithm many times. Both network topologies produce behavior consistent with experimental observations, and analysis of the parameter sets allows us to identify important network interactions and parameter constraints. We additionally screened these parameter sets for growth recovery in the presence of sub-saturating ethylene doses, which is an experimentally-observed property that emerges in some of the evolved parameter sets. Finally, we probed simplified networks maintaining key features of the CFF/NFB and PFB topologies. From this, we verified observations drawn from the larger networks about mechanisms underlying ethylene

  6. Analysis of Network Topologies Underlying Ethylene Growth Response Kinetics

    Directory of Open Access Journals (Sweden)

    Aaron M. Prescott

    2016-08-01

    Full Text Available Most models for ethylene signaling involve a linear pathway. However, measurements of seedling growth kinetics when ethylene is applied and removed have resulted in more complex network models that include coherent feedforward, negative feedback, and positive feedback motifs. However, the dynamical responses of the proposed networks have not been explored in a quantitative manner. Here, we explore (i whether any of the proposed models are capable of producing growth-response behaviors consistent with experimental observations and (ii what mechanistic roles various parts of the network topologies play in ethylene signaling. To address this, we used computational methods to explore two general network topologies: The first contains a coherent feedforward loop that inhibits growth and a negative feedback from growth onto itself (CFF/NFB. In the second, ethylene promotes the cleavage of EIN2, with the product of the cleavage inhibiting growth and promoting the production of EIN2 through a positive feedback loop (PFB. Since few network parameters for ethylene signaling are known in detail, we used an evolutionary algorithm to explore sets of parameters that produce behaviors similar to experimental growth response kinetics of both wildtype and mutant seedlings. We generated a library of parameter sets by independently running the evolutionary algorithm many times. Both network topologies produce behavior consistent with experimental observations and analysis of the parameter sets allows us to identify important network interactions and parameter constraints. We additionally screened these parameter sets for growth recovery in the presence of sub-saturating ethylene doses, which is an experimentally-observed property that emerges in some of the evolved parameter sets. Finally, we probed simplified networks maintaining key features of the CFF/NFB and PFB topologies. From this, we verified observations drawn from the larger networks about mechanisms

  7. Growth and physiological responses to water and nutrient stress in ...

    African Journals Online (AJOL)

    Administrator

    2011-09-07

    Sep 7, 2011 ... young carambola plants in relation to water stress. Sci. Hort. 60: 101-. 114. Jose S, Merritt S, Ramsey CL (2003). Growth, nutrition, photosynthesis and transpiration responses of longleaf pine seedlings to light, water and nitrogen. Forest Ecol Manag. 180: 335-344. Kallarackal J, Suman P, George J (2004).

  8. Evaluation of Growth Performance of Tomato in Response to ...

    African Journals Online (AJOL)

    Field experiment was conducted in 2013 and 2014 to evaluate growth performance of two tomato genotypes in response to biochar application and arbuscular mycorrhizal fungal (AMF) inoculation at the Teaching and Research Farm, Federal University of Agriculture, Abeokuta. The experiment was laid out in a split-split ...

  9. Evaluation of Growth Performance of Tomato in Response to ...

    African Journals Online (AJOL)

    Sunusi

    ABSTRACT. Field experiment was conducted in 2013 and 2014 to evaluate growth performance of two tomato genotypes in response to biochar application and arbuscular mycorrhizal fungal (AMF) inoculation at the. Teaching and Research Farm, Federal University of Agriculture, Abeokuta. The experiment was laid out.

  10. Growth and yield responses of sweet potato (ipomoea batatas) to ...

    African Journals Online (AJOL)

    Two field experiments were conducted at the Michael Okpara University of Agriculture, Umudike research farm in 2005 and 2006 wet seasons to determine the growth and yield responses of two sweet potato (Ipomoea batatas L. Lam) varieties viz TIS 87/0087 and TIS 8164 to time of potassium (K) fertilizer application in a ...

  11. Growth, Yield And Disease Responses Of 12 Cassava Genotypes ...

    African Journals Online (AJOL)

    Growth, Yield And Disease Responses Of 12 Cassava Genotypes Evaluated For Two Cropping Seasons In A Derived Savannah Zone Of South-Eastern Nigeria. ... TMS 96/0304 precluded their recommendation for release while TMS 96/1672 could be recommended for release to farmers. Agro-Science Vol. 7 (2) 2008: pp.

  12. Growth response of juveniles of Clarias bidorsalis to imported ...

    African Journals Online (AJOL)

    USER

    2010-08-02

    Aug 2, 2010 ... Growth response of Clarias bidorsalis juveniles weighing between 5 - 10 g that were fed with extruded. (floating) imported feed known as coppens were investigated for 84 days. In a simple experiment, 500 juveniles of C. bidorsalis were stocked in four experimental tanks with a dimension of 0.93 × 1.2 × ...

  13. Growth response and nutrient digestibility of pre-pubertal rabbit ...

    African Journals Online (AJOL)

    A study was conducted to investigate the growth response and nutrient digestibility in rabbit bucks fed cottonseed cake (CSC)-based diets supplemented with vitamin E. 64 weanling rabbit bucks, aged five to six weeks and weighing averagely 511.28 g were involved in the study. The bucks were randomly allocated to eight ...

  14. Effect of Mangifera Indica Leaves Extract on Growth Response of ...

    African Journals Online (AJOL)

    Effect of Mangifera indica leaves extracts on growth response of Oreochromis niloticus was evaluated for 42 days. 5 diets at approximately 40% crude protein containing varying levels of the extracts at 0%, 5%, 15% and 25% were formulated. These were fed to fingerlings of O. niloticus (mean weight, 5.25 – 6.05g) that were ...

  15. Growth response and heavy metals tolerance of Axonopus affinis ...

    African Journals Online (AJOL)

    Growth response and heavy metals tolerance of Axonopus affinis, inoculated with plant growthpromoting rhizobacteria. DL Cardón, SM Villafán, AR Tovar, SP Jiménez, LAG Zúñiga, MA Amezcua Allieri, NO Pérez, AR Dorantes ...

  16. Growth response of fluted pumpkin ( Telfairia occidentalis Hook . F ...

    African Journals Online (AJOL)

    An investigation of the growth response of fluted pumpkin to different combinations of irrigation intervals and spent mushroom substrate (SMS) was conducted during the dry season, with a view to determining the combination that would give the best performance of the crop. The experiment lasted for a period of thirteen ...

  17. Growth response of Heterobranchus longifilis fingerlings to Mucuna ...

    African Journals Online (AJOL)

    Laboratory studies on the growth responses of Heterobranchus longifilis fingerlings, mean weight 3.21 + 0.37g to Mucuna pruriens seed meals based diets were conducted for 70 days at the Federal College of Agriculture, Ishiagu in Ebonyi State, Nigeria. Mucuna pruriens seed meals were processed as either boiled or ...

  18. Survival And Growth Responses Of Frys Of The African Catfish ...

    African Journals Online (AJOL)

    Survival And Growth Responses Of Frys Of The African Catfish Hybrid ( Clarias gariepinus X Heterobranchus bidorsalis ) To Soluble Dietary Supplements Of ... The dietary treatments were fed to 4-weeks old hybrid of Clarias gariepinus × Heterobranchus bidorsalis (mean weight, 2.10 ± 0.14 g) at 5% body weight per day for ...

  19. Growth responses of tropical onion cultivars to photoperiod and ...

    African Journals Online (AJOL)

    Onions (Allium cepa L.) are widely produced within the tropics, but little is known about the Eritrean cultivars Hagaz Red 1 and 2 (HR 1, and HR 2) and Red Creole (RC). Responses of the onion cvs. HR 1, HR 2 and RC to photoperiod and temperature on bulbing were compared. Plants were grown in growth rooms under ...

  20. Growth response and apparent nutrient digestibility of weaner ...

    African Journals Online (AJOL)

    A ten-week feeding trial was conducted to determine the growth response and apparent nutrient digestibility of weaner rabbits fed with diets containing bamboo leaf meal (BLM). Eighty weaner rabbits were allotted into four dietary treatment groups of twenty rabbits each. The dietary treatment groups consisted of four rations ...

  1. Growth response of Ricinus communis L (castor oil) in spent ...

    African Journals Online (AJOL)

    The growth response of castor oil plant, Ricinus communis, in spent lubricating oil (SLO) was investigated using 1-6% w/w SLO and a control. The result showed that highest percent germination of approximately 92, was obtained in control and the least in 5% w/w. The early germination obtained in this study was significant ...

  2. Long-term salt stress responsive growth, carbohydrate metabolism ...

    African Journals Online (AJOL)

    We investigated the long-term responses of tobacco tissues to salt stress, with a particular interest for growth parameters, proline (Pro) accumulation, and carbohydrate metabolism. Exposure of 17-day-old tobacco plants to 0.2 M NaCl was followed by a higher decrease in dry matter in roots than shoots with a decrease of ...

  3. Growth and haematological response of growing rabbits to diets ...

    African Journals Online (AJOL)

    The growth and haematological response of growing rabbits to diets containing graded levels of Sun dried Bovine Rumen Content (SBRC) was studied for a period of ten weeks. The rumen content was collected from Nsukka abattoirs and dried in sun, ground and stored in sacks. The Composition of SBRC used in this ...

  4. Chenodeoxycholic acid stimulated fibroblast growth factor 19 response

    DEFF Research Database (Denmark)

    Borup, C; Wildt, S; Rumessen, J J

    2017-01-01

    BACKGROUND: Bile acid diarrhoea is underdiagnosed and better diagnostic tests are needed. Fasting serum fibroblast growth factor-19 (FGF19) has insufficient diagnostic value, but this may be improved by stimulation. AIM: To explore if an impaired FGF19 response identifies primary bile acid...

  5. Comparative leaf growth and grain yield responses of hybrid and ...

    African Journals Online (AJOL)

    Field experiment was conducted at the Teaching and Research Farm of the Faculty of Agriculture, University of Ilorin, Bolorunduro (8 29'N, 4 35'E) in the southern Guinea savanna of Nigeria, to compare the leaf growth and grain yield responses of hybrid and open-pollinated maize genotypes to nitrogen fertilizer application.

  6. Growth Response of Silver Fir and Bosnian Pine from Kosovo

    Directory of Open Access Journals (Sweden)

    Elvin Toromani

    2010-06-01

    Full Text Available Background and Purpose: This paper explore the growth-climate relationships in total ring width chronologies of silver fir (Abies alba Mill. and Bosnian pine (Pinus heldreichii Christ. The objective of this study is to quantify the climate influence on radial growth of both species. The relationships between climate and ring widths were analyzed using extreme growing years (called pointer years, simple correlations and response functions analysis (bootstrapped coefficients. The objectives of this study were: (1 to define the pattern of climatic response of each species, (2 to highlight the influence of local ecological conditions on tree's growth, and (3 to compare the response of silver fir and Bosnian pine to climate. Responses of total ring width to climate were estimated by establishing the mean relationship between growth and climate through simple correlations analysis and bootstrapped response functions. The response to climatic variability was also assessed by analyzing pointer years which correspond to abrupt changes in growth pattern and revealing the tree-growth response to extreme climatic events. For the period 1908-2008 the mean sensitivity (MS of total ring width chronology for Bosnian pine (0.209 was higher than silver fir (0.169 suggesting that Bosnian pine is more sensitive to climate (pointer years were more frequent in ring width chronology of Bosnian pine than in silver fir ring width chronology. The high values of first-order autocorrelations for Bosnian pine (0.674 indicated a strong dependence of current growth on the previous year’s growth. Pointer years analysis underlined the high sensitivity to spring temperatures and precipitation for both species. Radial growth for both species depends strongly on spring climate variables (temperatures and precipitation which play a significant role particularly for earlywood production. Material and Methods: We selected 12 silver fir trees and 15 Bosnian pine trees and took two 5

  7. Cdc42 GTPase dynamics control directional growth responses

    Science.gov (United States)

    Brand, Alexandra C.; Morrison, Emma; Milne, Stephen; Gonia, Sara; Gale, Cheryl A.; Gow, Neil A. R.

    2014-01-01

    Polarized cells reorient their direction of growth in response to environmental cues. In the fungus Candida albicans, the Rho-family small GTPase, Cdc42, is essential for polarized hyphal growth and Ca2+ influx is required for the tropic responses of hyphae to environmental cues, but the regulatory link between these systems is unclear. In this study, the interaction between Ca2+ influx and Cdc42 polarity-complex dynamics was investigated using hyphal galvanotropic and thigmotropic responses as reporter systems. During polarity establishment in an applied electric field, cathodal emergence of hyphae was lost when either of the two Cdc42 apical recycling pathways was disrupted by deletion of Rdi1, a guanine nucleotide dissociation inhibitor, or Bnr1, a formin, but was completely restored by extracellular Ca2+. Loss of the Cdc42 GTPase activating proteins, Rga2 and Bem3, also abolished cathodal polarization, but this was not rescued by Ca2+. Expression of GTP-locked Cdc42 reversed the polarity of hypha emergence from cathodal to anodal, an effect augmented by Ca2+. The cathodal directional cue therefore requires Cdc42 GTP hydrolysis. Ca2+ influx amplifies Cdc42-mediated directional growth signals, in part by augmenting Cdc42 apical trafficking. The Ca2+-binding EF-hand motif in Cdc24, the Cdc42 activator, was essential for growth in yeast cells but not in established hyphae. The Cdc24 EF-hand motif is therefore essential for polarity establishment but not for polarity maintenance. PMID:24385582

  8. Growth response of soda lake bacterial communities to simulated rainfall.

    Science.gov (United States)

    Krammer, M; Velimirov, B; Fischer, U; Farnleitner, A H; Herzig, A; Kirschner, A K T

    2008-02-01

    Moderately saline soda lakes harbor extremely abundant and fast growing bacterial communities. An interesting phenomenon of an explosive bacterial growth in shallow soda lakes in Eastern Austria after dilution with rainwater, concomitantly with a significant decrease in temperature was observed in a former study. In the present study, we tried to identify the factors being responsible for this enhanced bacterial growth in laboratory batch cultures. Three experiments were performed with water taken from two different lakes at different seasons. Natural soda lake water was diluted with distilled water, artificial lake water, sterile filtered soda lake water, and grazer-free water to test (1) for the influence of compatible solutes released to the environment and reduced salt stress after osmotic down-shock, (2) for the influence of nutrients, which may be washed in from the dry areas of the lake bottom after rainfall and (3) for the decrease of grazing pressure due to dilution. The potential influence of (4) viruses was indirectly deduced. The response of the bacterial community to the manipulations was measured by changes in bacterial numbers, the incorporation of (3)H-leucine and the concomitant determination of the amount of (3)H-leucine uptaking bacteria by microautoradiography. The influence of the environmental factors enhancing bacterial growth after a simulated rainfall event showed variations between the lakes and over the seasons. The addition of nutrients was, in all experiments, the main factor triggering bacterial growth. The decrease in grazing pressure and viral lysis after dilution was of significant importance in two of three experiments. In the experiment with the highest salinity, we could show that either compatible solutes released after osmotic down-shock and used as a source of nutrients for the soda lake bacterial populations or reduced salt stress were most probably responsible for the observed marked enhancement of bacterial growth.

  9. Differential Growth Responses of Marine Phytoplankton to Herbicide Glyphosate

    Science.gov (United States)

    Wang, Cong; Lin, Xin; Li, Ling; Lin, Senjie

    2016-01-01

    Glyphosate is a globally popular herbicide to kill weeds and its wide applications may lead to accumulation in coastal oceans as a source of phosphorus (P) nutrient or growth inhibitor of phytoplankton. We studied the physiological effects of glyphosate on fourteen species representing five major coastal phytoplankton phyla (haptophyta, bacillariophyta, dinoflagellata, raphidophyta, and chlorophyta). Based on growth responses to different concentrations of glyphosate under contrasting dissolved inorganic phosphorus (DIP) conditions, we found that phytoplankton species could be classified into five groups. Group I (Emiliania huxleyi, Skeletonema costatum, Phaeodactylum tricornutum) could utilize glyphosate as sole P-source to support growth in axenic culture, but in the presence of DIP, they were inhibited by both 36-μM and 360-μM glyphosate. Group II (Karenia mikimotoi, Prorocentrum minimum, Dunaliella tertiolecta, Symbiodinium sp., Heterosigma akashiwo and Alexandrium catenella) could not utilize glyphosate as sole P-source to support growth, and in the presence of DIP growth was not affected by 36-μM but inhibited by 360-μM glyphosate. Glyphosate consistently enhanced growth of Group III (Isochrysis galbana) and inhibited Group IV (Thalassiosira weissflogii, Thalassiosira pseudonana and Chattonella marina) regardless of DIP condition. Group V (Amphidinium carterae) exhibited no measurable response to glyphosate regardless of DIP condition. This grouping is not congruent with the phylogenetic relationships of the phytoplankton species suggesting functional differentiation driven by environmental pressure. We conclude that glyphosate could be used as P-source by some species while is toxic to some other species and yet has no effects on others. The observed differential effects suggest that the continued use of glyphosate and increasing concentration of this herbicide in the coastal waters will likely exert significant impact on coastal marine phytoplankton

  10. Genetic, molecular and functional analyses of complement factor I deficiency

    DEFF Research Database (Denmark)

    Nilsson, S.C.; Trouw, L.A.; Renault, N.

    2009-01-01

    Complete deficiency of complement inhibitor factor I (FI) results in secondary complement deficiency due to uncontrolled spontaneous alternative pathway activation leading to susceptibility to infections. Current genetic examination of two patients with near complete FI deficiency and three patie...

  11. Species differences in seedling growth and leaf water response to ...

    African Journals Online (AJOL)

    The effect of different levels of R:FR was studied on seedlings of four Ghanaian timber species of different ecological guilds to assess their growth and leaf water response to changes in R:FR. The experiment was conducted in shade houses of varying light qualities (0.30, 0.46 and 0.76 R:FR) achieved with the use of ...

  12. Type β transforming growth factor reversibly inhibits the early proliferative responsive to partial hepatectomy in the rat

    International Nuclear Information System (INIS)

    Russell, W.E.; Coffey, R.J. Jr.; Ouellette, A.J.; Moses, H.L.

    1988-01-01

    Type β transforming growth factor (TGF-β), a factor produced by many cell types, is a potent inhibitor of hepatocyte DNA synthesis in vitro. To determine whether TGF-β can influence hepatocyte proliferation in vivo, its effects were examined on the regenerative response of liver to partial hepatectomy (PH) in the rat. Porcine platelet-derived TGF-β1, administered intravenously at the time of PH and 11 hr later, reduced the fraction of hepatocytes engaged in DNA synthesis 22 hr after PH by 67% and inhibited the rate of hepatic [ 3 H]thymidine incorporation by 50%. TGF-β2 produced a similar effect. Although sensitive to TGF-β administered 11 hr after PH, late in the G 1 phase of the cell cycle, a single does of 0.5 μg given at the time of PH did not significantly influence DNA synthesis 22 hr after PH. The inhibitory effects of TGF-β were transient. The nuclear labeling index of the TGF-β-treated animals was significantly higher than that of the controls. There was no evidence of cytotoxicity from TGF-β, as determined by liver histology and plasma concentrations of glucose, insulin-like growth factor I, and two hepatic enzymes. Thus, TGF-β1 and TGF-β2 reversibly inhibit the proliferative response of liver to PH and may be important in the modulation of normal liver growth and repair

  13. Growth and stress response mechanisms underlying post-feeding regenerative organ growth in the Burmese python.

    Science.gov (United States)

    Andrew, Audra L; Perry, Blair W; Card, Daren C; Schield, Drew R; Ruggiero, Robert P; McGaugh, Suzanne E; Choudhary, Amit; Secor, Stephen M; Castoe, Todd A

    2017-05-02

    Previous studies examining post-feeding organ regeneration in the Burmese python (Python molurus bivittatus) have identified thousands of genes that are significantly differentially regulated during this process. However, substantial gaps remain in our understanding of coherent mechanisms and specific growth pathways that underlie these rapid and extensive shifts in organ form and function. Here we addressed these gaps by comparing gene expression in the Burmese python heart, liver, kidney, and small intestine across pre- and post-feeding time points (fasted, one day post-feeding, and four days post-feeding), and by conducting detailed analyses of molecular pathways and predictions of upstream regulatory molecules across these organ systems. Identified enriched canonical pathways and upstream regulators indicate that while downstream transcriptional responses are fairly tissue specific, a suite of core pathways and upstream regulator molecules are shared among responsive tissues. Pathways such as mTOR signaling, PPAR/LXR/RXR signaling, and NRF2-mediated oxidative stress response are significantly differentially regulated in multiple tissues, indicative of cell growth and proliferation along with coordinated cell-protective stress responses. Upstream regulatory molecule analyses identify multiple growth factors, kinase receptors, and transmembrane receptors, both within individual organs and across separate tissues. Downstream transcription factors MYC and SREBF are induced in all tissues. These results suggest that largely divergent patterns of post-feeding gene regulation across tissues are mediated by a core set of higher-level signaling molecules. Consistent enrichment of the NRF2-mediated oxidative stress response indicates this pathway may be particularly important in mediating cellular stress during such extreme regenerative growth.

  14. The molecular response of bone to growth hormone during skeletal unloading: regional differences

    Science.gov (United States)

    Bikle, D. D.; Harris, J.; Halloran, B. P.; Currier, P. A.; Tanner, S.; Morey-Holton, E.

    1995-01-01

    Hind limb elevation of the growing rat provides a good model for the skeletal changes that occur during space flight. In this model the bones of the forelimbs (normally loaded) are used as an internal control for the changes that occur in the unloaded bones of the hind limbs. Previous studies have shown that skeletal unloading of the hind limbs results in a transient reduction of bone formation in the tibia and femur, with no change in the humerus. This fall in bone formation is accompanied by a fall in serum osteocalcin (bone Gla protein, BGP) and bone BGP messenger RNA (mRNA) levels, but a rise in bone insulin-like growth factor-I (IGF-I) protein and mRNA levels and resistance to the skeletal growth-promoting actions of IGF-I. To determine whether skeletal unloading also induced resistance to GH, we evaluated the response of the femur and humerus of sham and hypophysectomized rats, control and hind limb elevated, to GH (two doses), measuring mRNA levels of IGF-I, BGP, rat bone alkaline phosphatase (RAP), and alpha 1(1)-procollagen (coll). Hypophysectomy (HPX) decreased the mRNA levels of IGF-I, BGP, and coll in the femur, but was either less effective or had the opposite effect in the humerus. GH at the higher dose (500 micrograms/day) restored these mRNA levels to or above the sham control values in the femur, but generally had little or no effect on the humerus. RAP mRNA levels were increased by HPX, especially in the femur. The lower dose of GH (50 micrograms/day) inhibited this rise in RAP, whereas the higher dose raised the mRNA levels and resulted in the appearance of additional transcripts not seen in controls. As for the other mRNAs, RAP mRNA in the humerus was less affected by HPX or GH than that in the femur. Hind limb elevation led to an increase in IGF-I, coll, and RAP mRNAs and a reduction in BGP mRNA in the femur and either had no effect or potentiated the response of these mRNAs to GH. We conclude that GH stimulates a number of markers of bone

  15. Radiation adaptive response for the growth of cultured glial cells

    International Nuclear Information System (INIS)

    Suzuki, S.; Miura, Y.; Kano, M.; Toda, T.; Urano, S.

    2003-01-01

    Full text: To examine the molecular mechanism of radiation adaptive response (RAR) for the growth of cultured glial cells and to investigate the influence of aging on the response, glial cells were cultured from young and aged rats (1 month and 24 months old). RAR for the growth of glial cells conditioned with a low dose of X-rays and subsequently exposed to a high dose of X-rays was examined for cell number and BrdU incorporation. Involvement of the subcellular signaling pathway factors in RAR was investigated using their inhibitors, activators and mutated glial cells. RAR was observed in cells cultured from young rats, but was not in cells from aged rats. The inhibitors of protein kinase C (PKC) and DNA-dependent protein kinase (DNA-PK) or phosphatidylinositol 3-kinase (PI3K) suppressed RAR. The activators of PKC instead of low dose irradiation also caused RAR. Moreover, glial cells cultured from severe combined immunodeficiency (scid) mice (CB-17 scid) and ataxia-telangiectasia (AT) cells from AT patients showed no RAR. These results indicated that PKC, ATM, DNAPK and/or PI3K were involved in RAR for growth and BrdU incorporation of cultured glial cells and RAR decreased with aging. Proteomics data of glial cells exposed to severe stress of H 2 O 2 or X-rays also will be presented in the conference since little or no difference has not been observed with slight stress yet

  16. 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 pH 1.5), and polyacrylic acid (25%, pH 3.9). Growth factors were detected in dentine matrix extracts drawn by 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

  17. Areva 2009 responsible growth report: more energy, less CO2

    International Nuclear Information System (INIS)

    2009-01-01

    This document is the 2009 annual responsible growth report of AREVA which presents itself as having consolidated its leadership position in its original business of nuclear power while expanding considerably in renewable energies (wind, solar, bio-energies and hydrogen/storage) to become a leading provider of solutions for carbon-free power generation. The main chapters of the report are: the group and its strategy, Areva's nuclear power solutions (is nuclear a sustainable energy source?, supply, technological excellence, safety, recycling and waste, acceptability, non-proliferation), Areva's renewable energy solutions (how much of the energy mix should be renewable?, rising demand, competitiveness and efficiency, responsible development), Areva's human resources (gender balance, health and safety, diversity and opportunity, hiring and training). Data and balanced scorecard for sustainable development are also given

  18. Growth response of microorganisms to different molecular fractions of lignite

    Energy Technology Data Exchange (ETDEWEB)

    Polman, J.K.; Breckenridge, C.R.; Dugan, P.R.; Quigley, D.R.

    1990-01-01

    Our research is primarily concerned with isolating and characterizing microbes which are able to dissimilate coal and convert it to other useful chemicals. This quarter, general growth responses of microorganisms cultivated in the presence of different molecular weight fractions of lignite coal were examined. Aerobic and anaerobic environmental samples from a variety of ecological niches were used as inocula. Growth of the microorganisms in these samples on the following types of media was tested: COAL medium, containing alkali-solubilized whole coal; THFI medium, containing the alkali-solubilized, tetrahydrofuran-insoluble, macromolecular portion of whole coal; THFS medium, containing the THF-soluble, low molecular weight portion of whole coal; and CON medium, void of any coal constituent. Overall results indicated that the presence of the THF-soluble, low molecular weight coal fraction enhanced the growth yield and the variety of aerobic microorganisms compared to the other coal fractions or the control medium. Conversely, anaerobic microbes grew best on media which contained the macromolecular fraction. 12 refs., 5 tabs.

  19. Growth response to ozone of annual species from Mediterranean pastures.

    Science.gov (United States)

    Gimeno, B S; Bermejo, V; Sanz, J; de la Torre, D; Elvira, S

    2004-11-01

    Ozone (O3) phytotoxicity has been reported on a wide range of plant species. However, scarce information has been provided regarding the sensitivity of semi-natural grassland species, especially those from dehesa Mediterranean grasslands, in spite of their great biological diversity and the high O3 levels recorded in the region. A screening study was carried out in open-top chambers (OTCs) to assess the O3-sensitivity of representative therophytes of these ecosystems based on the response of selected growth-related parameters. Three O3 treatments and 3 OTCs per treatment were used. Legume species were very sensitive to O3, because 78% of the tested species showed detrimental effects on their total biomass relative growth rate (RGR) following their exposure to O3. The Trifolium genus was particularly sensitive showing O3-induced adverse effects on most of the assessed parameters. Gramineae plants were less sensitive than Leguminosae species because detrimental effects on total biomass RGR were only observed in 14% of the assessed species. No relationship was found between relative growth rates when growing in clean air and O3 susceptibility. The implications of these effects on the performance of dehesa acidic grasslands and on the definition of ozone critical levels for the protection of semi-natural vegetation are discussed. Copyright 2004 Elsevier Ltd.

  20. Varied growth response of cogongrass ecotypes to elevated CO2

    Directory of Open Access Journals (Sweden)

    G. Brett Runion

    2016-01-01

    Full Text Available Cogongrass [Imperata cylindrica (L. P. Beauv] is an invasive C4 perennial grass which is listed as one of the top ten worst weeds in the world and is a major problem in the Southeast US. Five cogongrass ecotypes (Florida, Hybrid, Louisiana, Mobile, and North Alabama collected across the Southeast and a red-tip ornamental variety were container grown for six months in open top chambers under ambient and elevated (ambient plus 200 ppm atmospheric CO2. Elevated CO2 increased average dry weight (13% which is typical for grasses. Elevated CO2 increased height growth and both nitrogen and water use efficiencies, but lowered tissue nitrogen concentration; again, these are typical plant responses to elevated CO2. The hybrid ecotype tended to exhibit the greatest growth (followed by Louisiana, North Alabama, and Florida ecotypes while the red-tip and Mobile ecotypes were smallest. Interactions of CO2 with ecotype generally showed that the hybrid, Louisiana, Florida, and/or North Alabama ecotypes showed a positive response to CO2 while the Mobile and red-tip ecotypes did not. Cogongrass is a problematic invasive weed in the southeastern U.S. and some ecotypes may become more so as atmospheric CO2 continues to rise.

  1. Growth response to ozone of annual species from Mediterranean pastures

    Energy Technology Data Exchange (ETDEWEB)

    Gimeno, B.S. [Ecotoxicology of Air Pollution, CIEMAT (ed. 70), Avda, Complutense 22, 28040 Madrid (Spain)]. E-mail: benjamin.gimeno@ciemat.es; Bermejo, V. [Ecotoxicology of Air Pollution, CIEMAT (ed. 70), Avda, Complutense 22, 28040 Madrid (Spain)]. E-mail: Victoria.bermejo@ciemat.es; Sanz, J. [Ecotoxicology of Air Pollution, CIEMAT (ed. 70), Avda, Complutense 22, 28040 Madrid (Spain)]. E-mail: j.sanz@ciemat.es; Torre, D. de la [Ecotoxicology of Air Pollution, CIEMAT (ed. 70), Avda, Complutense 22, 28040 Madrid (Spain)]. E-mail: daniel.torre@ciemat.es; Elvira, S. [Ecotoxicology of Air Pollution, CIEMAT (ed. 70), Avda, Complutense 22, 28040 Madrid (Spain)]. E-mail: susana.elvira@ciemat.es

    2004-11-01

    Ozone (O{sub 3}) phytotoxicity has been reported on a wide range of plant species. However, scarce information has been provided regarding the sensitivity of semi-natural grassland species, especially those from dehesa Mediterranean grasslands, in spite of their great biological diversity and the high O{sub 3} levels recorded in the region. A screening study was carried out in open-top chambers (OTCs) to assess the O{sub 3}-sensitivity of representative therophytes of these ecosystems based on the response of selected growth-related parameters. Three O{sub 3} treatments and 3 OTCs per treatment were used. Legume species were very sensitive to O{sub 3}, because 78% of the tested species showed detrimental effects on their total biomass relative growth rate (RGR) following their exposure to O{sub 3}. The Trifolium genus was particularly sensitive showing O{sub 3}-induced adverse effects on most of the assessed parameters. Gramineae plants were less sensitive than Leguminosae species because detrimental effects on total biomass RGR were only observed in 14% of the assessed species. No relationship was found between relative growth rates when growing in clean air and O{sub 3} susceptibility. The implications of these effects on the performance of dehesa acidic grasslands and on the definition of ozone critical levels for the protection of semi-natural vegetation are discussed. - Capsule: The therophytes from dehesa acidic pastures of central of the Iberian peninsula present a great sensitivity to ozone, as derived from growth- and biomass-related variables.

  2. Insulin and insulin-like growth factor receptors and responses

    International Nuclear Information System (INIS)

    Roth, R.A.; Steele-Perkins, G.; Hari, J.; Stover, C.; Pierce, S.; Turner, J.; Edman, J.C.; Rutter, W.J.

    1988-01-01

    Insulin is a member of a family of structurally related hormones with diverse physiological functions. In humans, the best-characterized members of this family include insulin, insulin-like growth factor (IGF)-I, and IGF-II. Each of these three polypeptide hormones has its own distinct receptor. The structures of each of these receptors have now been deduced from analyses of isolated cDNA clones. To study further the responses mediated through these three different receptors, the authors have been studying cells expressing the proteins encoded by these three cDNAs. The isolated cDNAs have been transfected into Chinese hamster ovary (CHO) cells, and the resulting transfected cell lines have been characterized as to the ligand-binding activities and signal-transducing activities of the expressed proteins

  3. Growth and applicability of radiation-responsive silica nanowires

    Science.gov (United States)

    Bettge, Martin

    Surface energetics play an important role in processes on the nanoscale. Nanowire growth via vapor-liquid-solid (VLS) mechanism is no exception in this regard. Interfacial and line energies are found to impose some fundamental limits during three-phase nanowire growth and lead to formation of stranded nanowires with fascinating characteristics such as high responsiveness towards ion irradiation. By using two materials with a relatively low surface energy (indium and silicon oxide) this is experimentally and theoretically demonstrated in this doctoral thesis. The augmentation of VLS nanowire growth with ion bombardment enables fabrication of vertically aligned silica nanowires over large areas. Synthesis of their arrays begins with a thin indium film deposited on a Si or SiO 2 surface. At temperatures below 200ºC, the indium film becomes a self-organized seed layer of molten droplets, receiving a flux of atomic silicon by DC magnetron sputtering. Simultaneous vigorous ion bombardment through substrate biasing aligns the growing nanowires vertically and expedites mixing of oxygen and silicon into the indium. The vertical growth rate can reach up to 1000 nm-min-1 in an environment containing only argon and traces of water vapor. Silicon oxide precipitates from each indium seed in the form of multiple thin strands having diameters less than 9 nm and practically independent of droplet size. The strands form a single loose bundle, eventually consolidating to form one vertically aligned nanowire. These observations are in stark contrast to conventional VLS growth in which one liquid droplet precipitates a single solid nanowire and in which the precipitated wire diameter is directly proportional to the droplet diameter. The origin of these differences is revealed through a detailed force balance analysis, analogous to Young's relation, at the three-phase line. The liquid-solid interfacial energy of indium/silica is found to be the largest energy contribution at the three

  4. Growth Response and Tolerance to Heavy Metals of two Swamp Species inoculated with a Plant Growth-Promoting Rhizobacteria

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez-Dorantes, A.; Labra-Cardon, D.; Guerrero-Zuniga, A.; Montes-Villafan, S.

    2009-07-01

    Due to the sensitivity and the sequestration ability of the microbial communities to heavy metals, microbes have been used for bioremediation. Recently the application of plant growth-promoting rhizobacteria (PGPR) for the bioremediation of this kind of contaminants has been done. This study evaluated the growth response and the tolerance to heavy metals of two swamp species. (Author)

  5. Growth Response and Tolerance to Heavy Metals of two Swamp Species inoculated with a Plant Growth-Promoting Rhizobacteria

    International Nuclear Information System (INIS)

    Rodriguez-Dorantes, A.; Labra-Cardon, D.; Guerrero-Zuniga, A.; Montes-Villafan, S.

    2009-01-01

    Due to the sensitivity and the sequestration ability of the microbial communities to heavy metals, microbes have been used for bioremediation. Recently the application of plant growth-promoting rhizobacteria (PGPR) for the bioremediation of this kind of contaminants has been done. This study evaluated the growth response and the tolerance to heavy metals of two swamp species. (Author)

  6. Growth response of Juvenile Passion Fruit ( Passiflora Edulis , F ...

    African Journals Online (AJOL)

    ... and root, inorganic fertilizer produced significantly larger growth attributes than organic fertilizer and no fertilizer application. This indicates that 20 t ha-1 of organic fertilizer is sub-optimal for vigorous growth of passion fruit. Keywords: fertilizer, passion fruit, vegetative growth. Nigerian Journal of Horticultural Science Vol.

  7. Response of growth of tomato to phosphorus and nitrogen nutrition

    NARCIS (Netherlands)

    Groot, de C.C.; Marcelis, L.F.M.; Boogaard, van den R.; Lambers, H.

    2004-01-01

    A detailed growth analysis has been conducted to unravel the separate effects of nitrogen and phosphorus nutrition on growth of young tomato plants (Lycopersicon esculentum Mill. cv. Capita) and to study their interaction. We show that relative growth rate increased sharply with increasing plant P

  8. Metabolic response to human growth hormone during prolonged starvation.

    Science.gov (United States)

    Felig, P; Marliss, E B; Cahill, G F

    1971-02-01

    The metabolic response to human growth hormone (HGH) was studied in five obese subjects in the fed state and during prolonged (5-6 wk) starvation. In the fed state (three subjects), HGH induced an elevation in basal serum insulin concentration, a minimal increase in blood and urine ketone levels, and a marked reduction in urinary nitrogen and potassium excretion resulting in positive nitrogen and potassium balance. In prolonged fasting (four subjects), HGH administration resulted in a 2- to 3-fold increase in serum insulin which preceded a 50% elevation in blood glucose. Persistence of the lipolytic effects of HGH was indicated by a rise in free fatty acids and glycerol. The response differed markedly from the fed state in that blood beta-hydroxybutyrate and acetoacetate levels rose by 20-40%, resulting in total blood ketone acid concentrations of 10-12 mmoles/liter, ketonuria of 150-320 mmoles/day, and increased urinary potassium loss. The subjects complained of nausea, vomiting, weakness, and myalgias. Despite a 50% reduction in urea excretion during HGH administration, total nitrogen loss remained unchanged as urinary ammonia excretion rose by 50% and correlated directly with the degree of ketonuria. It is concluded that in prolonged starvation (a) HGH may have a direct insulinotropic effect on the beta cell independent of alterations in blood glucose concentration, (b) persistence of the lipolytic action of HGH results in severe exaggeration of starvation ketosis and interferes with its anticatabolic action by necessitating increased urinary ammonia loss, and (c) failure of HGH to reduce net protein catabolism in starvation suggests that this hormone does not have a prime regulatory role in conserving body protein stores during prolonged fasting.

  9. Segmental heterogeneity of enzymatic response during compensatory renal growth

    International Nuclear Information System (INIS)

    Hoang, T.; Bergeron, M.

    1985-01-01

    The activities of DNA polymerase α and key enzymes of gluconeogenesis and glycolysis were measured in different segments of the rat nephron at various times (up to 96 hrs) following a unilateral nephrectomy (UNx). Tubule fragments were obtained after collagenase treatment followed by centrifugation on a Percoll gradient. The DNA polymerase α activity in control rats showed moderate and similar values in different segmental extracts as well as in the whole kidney extract (1700-1800 μμmole[ 3 H] dAMP/mg DNA). In Unx rats, activity in proximal tubules (PT) measured at 24, 48, 72 and 96 hrs after nephrectomy represented an increase of 60%, 200%, 420% and 370% respectively over control values. Distal tubule fragments (DT) showed only minor increases. The results demonstrate that the proximal tubule accounts for most of the compensatory renal growth (CRG) in the remaining kidney. The gluconeogenic and glycolytic enzymes were confined to the PT and those of glycolysis to the DT fragments. Following UNx, the specific activities of these enzymes were not modified in the remaining kidney; however, the overall activity of gluconeogenesis was increased as a result of the cell hyperplasia occurring in the PT. The work also illustrates that biochemical studies of CRG on the whole organ may provide misleading information due to the presence of heterogeneous cell populations in the mammalian kidney and to their uneven response in CRG

  10. Growth and photosynthetic responses of wheat plants grown in space.

    Science.gov (United States)

    Tripathy, B C; Brown, C S; Levine, H G; Krikorian, A D

    1996-03-01

    Growth and photosynthesis of wheat (Triticum aestivum L. cv Super Dwarf) plants grown onboard the space shuttle Discovery for 10 d were examined. Compared to ground control plants, the shoot fresh weight of space-grown seedlings decreased by 25%. Postflight measurements of the O2 evolution/photosynthetic photon flux density response curves of leaf samples revealed that the CO2-saturated photosynthetic rate at saturating light intensities in space-grown plants declined 25% relative to the rate in ground control plants. The relative quantum yield of CO2-saturated photosynthetic O2 evolution measured at limiting light intensities was not significantly affected. In space-grown plants, the light compensation point of the leaves increased by 33%, which likely was due to an increase (27%) in leaf dark-respiration rates. Related experiments with thylakoids isolated from space-grown plants showed that the light-saturated photosynthetic electron transport rate from H2O through photosystems II and I was reduced by 28%. These results demonstrate that photosynthetic functions are affected by the microgravity environment.

  11. Modelling of tomato stem diameter growth rate based on physiological responses

    International Nuclear Information System (INIS)

    Li, L.; Tan, J.; Lv, T.

    2017-01-01

    The stem diameter is an important parameter describing the growth of tomato plant during vegetative growth stage. A stem diameter growth model was developed to predict the response of plant growth under different conditions. By analyzing the diurnal variations of stem diameter in tomato (Solanum lycopersicum L.), it was found that the stem diameter measured at 3:00 am was the representative value as the daily basis of tomato stem diameter. Based on the responses of growth rate in stem diameter to light and temperature, a linear regression relationship was applied to establish the stem diameter growth rate prediction model for the vegetative growth stage in tomato and which was further validated by experiment. The root mean square error (RMSE) and relative error (RE) were used to test the correlation between measured and modeled stem diameter variations. Results showed that the model can be used in prediction for stem diameter growth rate at vegetative growth stage in tomato. (author)

  12. Growth Response of Juvenile Catfish ( Clarias gariepinus ) Fed ...

    African Journals Online (AJOL)

    The inclusion of Lactobacillus in the diet of C.gariepinus juvenile gave better FCR an indication that profitable and sustainable aquaculture can be successfully achieved by the inclusion of Lactobacillus in feeds. Keywords: Bacteria, growth, haematology, probiotics, feed, clarias gariepinus. Fish, Feed, Probiotics, growth, ...

  13. Nutrient Utilization And Growth Responses Of The Frys Of The ...

    African Journals Online (AJOL)

    A non-P-supplemented diet and a purified diet served as controls. Growth of fish was monitored by weekly protein intake, protein efficiency ratio, nitrogen metabolism, feed conversion, specific growth rate and gain or loss of tissue protein. Proximate composition of the diet was determined. The results showed that the ...

  14. Response of barley plants to foliar application of growth regulators ...

    African Journals Online (AJOL)

    The obtained results revealed that either foliar spraying by the growth regulators mixture or Zinc concentrations had a significant promotive effect on the studied growth and yield as well as the physiological and chemical parameters of barley when compared with the control treatment. While the highest values of the previous ...

  15. Plant responses to plant growth-promoting rhizobacteria

    NARCIS (Netherlands)

    Loon, L.C. van

    2007-01-01

    Non-pathogenic soilborne microorganisms can promote plant growth, as well as suppress diseases. Plant growth promotion is taken to result from improved nutrient acquisition or hormonal stimulation. Disease suppression can occur through microbial antagonism or induction of resistance in the plant.

  16. Growth response and nutrient digestibility of growing pigs to ...

    African Journals Online (AJOL)

    Feed restriction is a relevant management tool use in modificationof livestock growth patterns by reducing their maintenance requirement, leading to improved feed efficiency and utilization. This study assessed the effect of qualitative and quantitative feed restriction on growth parameters and nutrients digestibility of growing ...

  17. Quality control system response to stochastic growth of amyloid fibrils

    DEFF Research Database (Denmark)

    Pigolotti, Simone; Lizana, Ludvig; Otzen, Daniel

    2013-01-01

    We introduce a stochastic model describing aggregation of misfolded proteins and degradation by the protein quality control system in a single cell. Aggregate growth is contrasted by the cell quality control system, that attacks them at different stages of the growth process, with an efficiency t...

  18. Growth responses of Escherichia coli and Myxococcus xanthus on ...

    African Journals Online (AJOL)

    Bacteria colonize surfaces responding to the physicochemical properties of substrates. A systematic study was carried out with growing single bacterial colonies on the surface of agar media to decipher the interaction between bacterial growth and substrate stiffness. We investigated the growth kinetics of wild-type ...

  19. Provenance-specific growth responses to drought and air warming in three European oak species

    Energy Technology Data Exchange (ETDEWEB)

    Arend, Matthias; Kuster, Thomas; Gunthardt-Goerg, Madeleine S.; Dobbertin, Matthias

    2011-03-15

    This study evaluated oak growth responses to air warming through research conducted with species coming from climatically different sites submitted to differing climates including periodic drought and air warming. Results showed different responses to drought and air warming as an adaptation to the conditions, and differences in growth response from one provenance to another were found but local climate factors were not responsible. This study highlighted that provenance was important to growth responses and it will have to be taken into account for regeneration of oaks in a changed climate if these results are confirmed.

  20. EXO modifies sucrose and trehalose responses and connects the extracellular carbon status to growth

    Directory of Open Access Journals (Sweden)

    Janina eLisso

    2013-06-01

    Full Text Available Plants have the capacity to adapt growth to changing environmental conditions. This implies the modulation of metabolism according to the availability of carbon (C. Particular interest in the response to the C availability is based on the increasing atmospheric levels of CO2. Several regulatory pathways that link the C status to growth have emerged. The extracellular EXO protein is essential for cell expansion and promotes shoot and root growth. Homologous proteins were identified in evolutionarily distant green plants. We show here that the EXO protein connects growth with C responses. The exo mutant displayed altered responses to exogenous sucrose supplemented to the growth medium. Impaired growth of the mutant in synthetic medium was associated with the accumulation of starch and anthocyanins, altered expression of sugar-responsive genes, and increased abscisic acid levels. Thus, EXO modulates several responses related to the C availability. Growth retardation on medium supplemented with 2-deoxy-glucose, mannose, and palatinose was similar to the wild type. Trehalose feeding stimulated root growth and shoot biomass production of exo plants whereas it inhibited growth of the wild type. The phenotypic features of the exo mutant suggest that apoplastic processes coordinate growth and C responses.

  1. Comparison of response to 2-years’ growth hormone treatment in children with isolated growth hormone deficiency, born small for gestational age, idiopathic short stature, or multiple pituitary hormone deficiency: combined results from two large observational studies

    Directory of Open Access Journals (Sweden)

    Lee Peter A

    2012-07-01

    Full Text Available Abstract Background Few studies have compared the response to growth hormone (GH treatment between indications such as isolated growth hormone deficiency (IGHD, born small for gestational age (SGA, idiopathic short stature (ISS, and multiple pituitary hormone deficiency (MPHD. The aim of this analysis of data, collected from two large ongoing observational outcome studies, was to evaluate growth and insulin-like growth factor-I (IGF-I response data for children of short stature with IGHD, MPHD, SGA, or ISS following two years of treatment with the recombinant GH product Norditropin® (Novo Nordisk A/S, Bagsværd, Denmark. Methods Analysis of auxologic data from two ongoing prospective observational studies, NordiNet® International Outcomes Study (NordiNet® IOS and NovoNet®/American Norditropin® Studies: Web-enabled Research (ANSWER Program®. Results 4,582 children aged p = 0.047; p  0.001 vs. IGHD, respectively. Height gain was comparable between IGHD and MPHD. In pre-pubertal children vs. total population, height SDS change after two years was: IGHD, +1.24 vs. +0.97; SGA, +1.17 vs. +1.03; ISS, +1.04 vs. +0.84; and MPHD, +1.16 vs. +0.99 (all p  Conclusions After two years’ GH treatment, change in height SDS was greater in SGA and less in ISS, compared with IGHD; the discrepancy in responses may be due to the disease nature or confounders (i.e. age. Height SDS increase was greatest in pre-pubertal children, supporting early treatment initiation to optimize growth outcomes.

  2. Long-term Root Growth Response to Thinning, Fertilization, and Water Deficit in Plantation Loblolly Pine

    Science.gov (United States)

    M.A. Sword-Sayer; Z. Tang

    2004-01-01

    High water deficits limit the new root growth of loblolly pine (Pinus taeda L.), potentially reducing soil resource availability and stand growth. We evaluated new root growth and stand production in response to thinning and fertilization in loblolly pine over a 6-year period that consisted of 3 years of low water deficit followed by 3 years of high...

  3. Comparative evaluation of short-term biomarker response to treatment for growth hormone deficiency in Chinese children with growth hormone deficiency born small for or appropriate for gestational age: a randomized phase IV open-label study.

    Science.gov (United States)

    Lu, Wenli; Shen, Shuixian; Luo, Xiaoping; Gong, Chunxiu; Gu, Xuefan; Li, Yun; Du, Minlian; Jin, Runming; Zhou, Queena; Wang, Wei

    2013-04-01

    To compare the response between Chinese children with growth hormone deficiency (GHD) born either small for gestational age (SGA) or appropriate for gestational age (AGA) after 4 weeks of recombinant human growth hormone (r-hGH) therapy. This was a phase IV, open-label, multicenter, interventional study (NCT01187550). Prepubertal children with GHD received open-label treatment with daily r-hGH (0.033 mg/kg) for 4 weeks. Serum levels of insulin-like growth factor I (IGF-I) and insulin-like growth factor-binding protein 3 (IGFBP3), and metabolic markers (including fasting glucose, insulin, total cholesterol, and homeostasis model assessment of insulin resistance) were assessed at baseline and after 4 weeks of treatment, and were analyzed according to patient subgroup (SGA or AGA). A total of 205 children with GHD (mean age 10.4 years; 175 AGA, 30 SGA) were included in the analysis. Mean baseline serum IGF-I and IGFBP3 standard deviation scores (SDS) across the whole patient population were lower than the population norms (mean values: -2.1 SDS for IGF-I and -1.2 SDS for IGFBP3), with no significant differences between the two patient subgroups. After 4 weeks, IGF-I and IGFBP3 levels increased by 1.0 SDS (p < 0.001) and 0.34 SDS (p < 0.001), respectively, but no significant differences were found between the two patient subgroups for growth-related or metabolic markers. For children with GHD born SGA, IGF-I and IGFBP3 are short-term biomarkers of responsiveness to treatment with growth hormone, as for children with GHD born AGA.

  4. Report on responsible growth. AREVA in 2008; Rapport de croissance responsable. AREVA en 2008

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2009-07-01

    All over the world, AREVA supplies its customers with solutions for carbon-free power generation and electricity transmission and distribution. With its knowledge and expertise in these fields, the group has a leading role to play in meeting the world's energy needs. Ranked first in the global nuclear power industry, AREVA's unique integrated offering covers every stage of the fuel cycle, reactor design and construction, and related services. In addition, the group is expanding its operations in renewable energies. AREVA is also a world leader in electricity transmission and distribution and offers its customers a complete range of solutions for greater grid stability and energy efficiency. Sustainable development is a core component of the group's industrial strategy. Its 75,000 employees work every day to make AREVA a responsible industrial player that is helping to supply ever cleaner, safer and more economical energy to the greatest number of people. Sustainable development is a keystone of AREVA's industrial strategy for achieving growth that is profitable, socially responsible and respectful of the environment. To translate this choice into reality, AREVA integrates sustainable development into its management practices via a continuous improvement initiative revolving around ten commitments: customer satisfaction, financial performance, governance, community involvement, environmental protection, innovation, continuous improvement, commitment to employees, risk management and prevention, dialogue and consensus building. This document is Areva's 2008 report on responsible growth. After the Messages from the Chairman of the Supervisory Board and from the Chief Executive Officer, the report presents the Key data and Highlights of the period, the Corporate governance, the Organization of the group, the Share information and shareholder relations, the uranium reserves, the growing energy demand and the World's population demographic

  5. Growth and other physiological responses of bivalves in laboratory experiments

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Milford lab maintains data sets relating to a variety of growth and physiology trials. These include husbandry techniques (i.e. stocking density, container size,...

  6. Factors responsible for the growth of small business

    Directory of Open Access Journals (Sweden)

    JA Döckel

    2015-01-01

    Full Text Available Entrepreneurial conduct holds the key to economic growth. Thus those business that show growth and development are considered entrepreneurial, implying that SMME policy initiatives should focus on businesses with growth potential, and not the small business sector as a whole.  The success of a small business seems to depend on the intentions of the owner, together with factors associated with the ability of, and opportunity for, the specific business to grow.  The aim of this article is to make use of a multiple linear regression model to determine the variables that impact positively on business growth.  In addition to demand factors, it was established that smaller and younger businesses are the ones that grow faster. A successful business also shows a positive correlation between business management skills and entrepreneurial conduct.

  7. African Jobless Growth Morphology:Vulnerabilities and Policy Responses

    OpenAIRE

    NWAOBI, GODWIN

    2013-01-01

    As by product of economic growth, jobs are indeed transformational. In other words, efficiency increases as workers get better at what they do (as more productive jobs appear and less productive one disappear). In fact societies flourish as jobs bring together people from different ethnic and social backgrounds while providing alternatives to conflict. Unfortunately, in many African countries, unemployment rates are low and growth is seldom jobless. Regrettably, most of the poor work long ho...

  8. Xylem traits, leaf longevity and growth phenology predict growth and mortality response to defoliation in northern temperate forests.

    Science.gov (United States)

    Foster, Jane R

    2017-09-01

    Defoliation outbreaks are biological disturbances that alter tree growth and mortality in temperate forests. Trees respond to defoliation in many ways; some recover rapidly, while others decline gradually or die. Functional traits such as xylem anatomy, growth phenology or non-structural carbohydrate (NSC) storage could explain these responses, but idiosyncratic measures used by defoliation studies have frustrated efforts to generalize among species. Here, I test for functional differences with published growth and mortality data from 37 studies, including 24 tree species and 11 defoliators from North America and Eurasia. I synthesized data into standardized variables suitable for numerical models and used linear mixed-effects models to test the hypotheses that responses to defoliation vary among species and functional groups. Standardized data show that defoliation responses vary in shape and degree. Growth decreased linearly or curvilinearly, least in ring-porous Quercus and deciduous conifers (by 10-40% per 100% defoliation), whereas growth of diffuse-porous hardwoods and evergreen conifers declined by 40-100%. Mortality increased exponentially with defoliation, most rapidly for evergreen conifers, then diffuse-porous, then ring-porous species and deciduous conifers (Larix). Goodness-of-fit for functional-group models was strong (R2c = 0.61-0.88), if lower than species-specific mixed-models (R2c = 0.77-0.93), providing useful alternatives when species data are lacking. These responses are consistent with functional differences in leaf longevity, wood growth phenology and NSC storage. When defoliator activity lags behind wood-growth, either because xylem-growth precedes budburst (Quercus) or defoliator activity peaks later (sawflies on Larix), impacts on annual wood-growth will always be lower. Wood-growth phenology of diffuse-porous species and evergreen conifers coincides with defoliation and responds more drastically, and lower axial NSC storage makes them

  9. Identification of factors associated with good response to growth hormone therapy in children with short stature: results from the ANSWER Program®

    Directory of Open Access Journals (Sweden)

    Khutoryansky Naum

    2011-07-01

    Full Text Available Abstract Objective To identify factors associated with growth in children on growth hormone (GH therapy using data from the American Norditropin Studies: Web-enabled Research (ANSWER Program® registry. Methods GH-naïve children with GH deficiency, multiple pituitary hormone deficiency, idiopathic short stature, Turner syndrome, or a history of small for gestational age were eligible (N = 1,002. Using a longitudinal statistical approach, predictive factors were identified in patients with GHD for change from baseline in height standard deviation score (ΔHSDS following 2 years of treatment. Results Gradual increases in ΔHSDS over time were observed for all diagnostic categories. Significant predictive factors of ΔHSDS, ranked by significance were: height velocity (HV at 4 months > baseline age > baseline HSDS > baseline body mass index (BMI SDS > baseline insulin-like growth factor I (IGF-I SDS; gender was not significant. HV at 4 months and baseline BMI SDS were positively correlated, whereas baseline age, HSDS, and IGF-I SDS were negatively correlated with ΔHSDS. Conclusions These results may help guide GH therapy based on pretreatment characteristics and early growth response.

  10. Growth rate regulated genes and their wide involvement in the Lactococcus lactis stress responses

    Directory of Open Access Journals (Sweden)

    Redon Emma

    2008-07-01

    Full Text Available Abstract Background The development of transcriptomic tools has allowed exhaustive description of stress responses. These responses always superimpose a general response associated to growth rate decrease and a specific one corresponding to the stress. The exclusive growth rate response can be achieved through chemostat cultivation, enabling all parameters to remain constant except the growth rate. Results We analysed metabolic and transcriptomic responses of Lactococcus lactis in continuous cultures at different growth rates ranging from 0.09 to 0.47 h-1. Growth rate was conditioned by isoleucine supply. Although carbon metabolism was constant and homolactic, a widespread transcriptomic response involving 30% of the genome was observed. The expression of genes encoding physiological functions associated with biogenesis increased with growth rate (transcription, translation, fatty acid and phospholipids metabolism. Many phages, prophages and transposon related genes were down regulated as growth rate increased. The growth rate response was compared to carbon and amino-acid starvation transcriptomic responses, revealing constant and significant involvement of growth rate regulations in these two stressful conditions (overlap 27%. Two regulators potentially involved in the growth rate regulations, llrE and yabB, have been identified. Moreover it was established that genes positively regulated by growth rate are preferentially located in the vicinity of replication origin while those negatively regulated are mainly encountered at the opposite, thus indicating the relationship between genes expression and their location on chromosome. Although stringent response mechanism is considered as the one governing growth deceleration in bacteria, the rigorous comparison of the two transcriptomic responses clearly indicated the mechanisms are distinct. Conclusion This work of integrative biology was performed at the global level using transcriptomic analysis

  11. Growth hormone, prolactin and cortisol response to exercise in patients with depression

    DEFF Research Database (Denmark)

    Krogh, Jesper; Nordentoft, Merete; Mohammad-Nezhad, Mahdi

    2010-01-01

    . CONCLUSIONS: Patients with mild to moderate depression had a different growth hormone and cortisol response to acute exercise stress compared to healthy controls. Strength training was able to reduce the growth hormone response to acute exercise stress in this patient population. Studies with more rigorous......BACKGROUND: A blunted growth hormone and prolactin response to pharmacological stress test have previously been found in depressed patients, as well as an increased cortisol response to psychosocial stress. This study investigated these hormones in response to acute exercise using an incremental...... bicycle test. METHOD: A cross-sectional comparison of cortisol, growth hormone, and prolactin in depressed (n=137) and healthy (n=44) subjects during rest and in response to an incremental bicycle test. Secondly, we tested the depressed patients again after a 4-month randomized naturalistic exercise...

  12. Diatom growth responses to photoperiod and light are predictable from diel reductant generation.

    Science.gov (United States)

    Li, Gang; Talmy, David; Campbell, Douglas A

    2017-02-01

    Light drives phytoplankton productivity, so phytoplankton must exploit variable intensities and durations of light exposure, depending upon season, latitude, and depth. We analyzed the growth, photophysiology and composition of small, Thalassiosira pseudonana, and large, Thalassiosira punctigera, centric diatoms from temperate, coastal marine habitats, responding to a matrix of photoperiods and growth light intensities. T. pseudonana showed fastest growth rates under long photoperiods and low to moderate light intensities, while the larger T. punctigera showed fastest growth rates under short photoperiods and higher light intensities. Photosystem II function and content responded primarily to instantaneous growth light intensities during the photoperiod, while diel carbon fixation and RUBISCO content responded more to photoperiod duration than to instantaneous light intensity. Changing photoperiods caused species-specific changes in the responses of photochemical yield (e - /photon) to growth light intensity. These photophysiological variables showed complex responses to photoperiod and to growth light intensity. Growth rate also showed complex responses to photoperiod and growth light intensity. But these complex responses resolved into a close relation between growth rate and the cumulative daily generation of reductant, across the matrix of photoperiods and light intensities. © 2016 The Authors. Journal of Phycology published by Wiley Periodicals, Inc. on behalf of Phycological Society of America.

  13. Effect of Trichoderma isolates on tomato seedling growth response ...

    African Journals Online (AJOL)

    Jane

    2011-06-29

    Jun 29, 2011 ... Trichoderma species are commonly used as biological control agents against phytopathogenic fungi and some isolates are able to improve plant growth. In this study, the effects of three Trichoderma isolates including Trichoderma harzianum isolate T969, T. harzianum isolate T447 and Trichoderma sp.

  14. Growth, assimilate partitioning and grain yield response of soybean ...

    African Journals Online (AJOL)

    Abstract. This investigation tested variation in the growth components, assimilate partitioning and grain yield of soybean (Glycine max L. Merrrill) varieties established in CO2 enriched atmosphere when inoculated with mixtures of Arbuscular mycorrhizal fungi (AMF) species in the humid rainforest of Nigeria. A pot and a field ...

  15. Growth, ion content and photosynthetic responses of two Elytrigia ...

    African Journals Online (AJOL)

    Jane

    2011-07-25

    Jul 25, 2011 ... reported that in naked oat (Avena nuda L.), salt stress applied at their lowest treatment level (50 mM) reduced total leaf area (TLA) by 35% and plant dry matter (PDM) by 52%. Under a higher salinity level (250 mM), plant growth was further suppressed, causing decreases of 91 and 86% in TLA and PDM, ...

  16. Growth and biomass yield response of clover ( Trifolium decorum ...

    African Journals Online (AJOL)

    Low soil fertility status is a dominant challenge in Ethiopian agriculture for decades. Organic amendment from different sources could help to rebuild the soil fertility status of the country. Hence, an experiment was conducted to evaluate the outcome of organic treatment and preceding crops on growth and biomass yield of ...

  17. Effects of feed forms on growth pattern, behavioural responses and ...

    African Journals Online (AJOL)

    Growth pattern, faecal microbial load and behavioural activities (eating, drinking, physical pen interaction and frequency of visiting the drinking troughs) were assessed in 49 days. Pigs fed dry mash without probiotics (T1) had the highest daily feed intake among the experimental animals (1.10kg) while pigs on ...

  18. Growth rhythms in sunflower ( Helianthus annuus L.) in response to ...

    African Journals Online (AJOL)

    Sunflower hybrids maintain high level of stability in a variety of environments. Environmental variations affect and modify plant attributes like growth, development and assimilation through physio-morphic functions, thus modifying plant phenology. Field experiments, one each in spring and autumn, were conducted at Pir ...

  19. Growth response of Casuarina equisetifolia Forst. rooted stem ...

    Indian Academy of Sciences (India)

    2013-10-01

    Oct 1, 2013 ... nutrient-deficient farm land. The results showed that the rooted stem cuttings of C. equisetifolia significantly improved growth in height (8.8 m), stem girth (9.6 cm) and tissue nitrogen content (3.3 mg g. −1. ) than uninoculated controls. The soil nutrient status was also improved due to inoculation of Frankia.

  20. Nodulation and growth response of Sesbania sesban (L.) Merr. to ...

    African Journals Online (AJOL)

    A glasshouse experiment was carried out to study the effect of ammonium-N on the nodulation, growth and N-uptake of Sesbania sesban (L.) Merr. inoculated with an effective Mesorhizobium (S. sesban) strain. Ammonium-N was supplied twice weekly as 100 ml of nutrient solution at concentrations of 0, 100, 200, 400, 600 ...

  1. Growth, physiology and yield responses of Amaranthus cruentus ...

    African Journals Online (AJOL)

    Amaranthus cruentus, Corchorus olitorius and Vigna unguiculata are traditional leafy vegetables with potential to improve nutritional security of vulnerable people. The promotion of these crops is partly hindered by the lack of agronomic information. The effect of plant spacing on growth, physiology and yield of these three ...

  2. Growth, phenological and yield responses of a bambara groundnut ...

    African Journals Online (AJOL)

    Effects of irrigation levels and seed coat colour on growth, development, yield and water-use efficiency of local bambara groundnut landrace selections were evaluated under a rain shelter. Emergence was slow, although variation was indicated between landraces. Limited water availability was shown to lower stomatal ...

  3. Growth responses to ozone in plant species from wetlands

    NARCIS (Netherlands)

    Franzaring, J.H.; Tonneijck, A.E.G.; Kooijman, A.W.N.; Dueck, Th.A.

    2000-01-01

    Ten wet grassland species were fumigated with four concentrations of ozone (charcoal-filtered air, non-filtered air and non-filtered air plus 25 or 50 nl 1-1 ozone) in open-top chambers during one growing season to investigate the long-term effect of this air pollutant on various growth variables.

  4. Growth and yield responses of pawpaw varieties (Carica Papaya l ...

    African Journals Online (AJOL)

    Intercropping significantly decreased pawpaw plant height, stem girth, number of leaves, leaf area and canopy spread in the first year while it sustained LER. The LER, growth and yield in both ... papaya could be inter-cropped with vegetable at the early vegetative stages to sustain land utilization as well as total productivity.

  5. Growth Response and Susceptibility of Telparia Occidentalis Hook ...

    African Journals Online (AJOL)

    ... gall rating and egg-mass were highly significant. Fresh shoot weight was negatively correlated with all the measured indices of nematode infection, but they were not significant.. Keywords: Growth, susceptibility, root-knot nematodes, Telfairia occidentalis. Nigerian Journal of Horticultural Science Vol. 10 2005: pp. 52-58 ...

  6. Growth and photosynthesis responses of Rosmarinus officinalis L. to ...

    African Journals Online (AJOL)

    Despite this decrease, we do not observe any visual phytotoxicity symptom. This aromatic and medicinal species, belonging to Lamiaceae family, could be used as alternative crops in polluted soils. Keywords: Rosmarinus officinalis L., zinc, lead, growth, photosynthesis, “Bougrine” mine. African Journal of Biotechnology Vol ...

  7. Growth response of fluted pumpkin (Telfairia occidentalis Hook. F) to ...

    African Journals Online (AJOL)

    user

    2011-10-06

    Oct 6, 2011 ... will not burn crop upon application. Furthermore, SMS contains a wealth of micronutrients that are usually not present in standard NPK fertilizers. ..... characteristics and growth benefits of four composted organic waste products on field grown woody nursery stock. Proceedings, spent. Mushroom substrate ...

  8. Growth and Yield Responses of Vegetable Cowpea ( Vigna ...

    African Journals Online (AJOL)

    The amendment of acidic soil with lime application enhances nutrient availability for optimum vegetable cowpea production. Field experiments were conducted in the teaching and research farm of Michael Okpara University of Agriculture, Umudike during 2006 and 2007 cropping seasons to determine the growth and yield ...

  9. Bone growth response with porous hydroxyapatite granules in a

    Indian Academy of Sciences (India)

    Bone growth with porous hydroxyapatite granules 147 granules. Yet few gaps still persisted between the new bone and the granules. Morphologically the granules did not show any signs of degradation. Formation of the. Haversian system and the maturation of woven bone were observed (figure 7b). 12 weeks: The defect ...

  10. Growth Response of Selected Mangrove Species to Domestic ...

    African Journals Online (AJOL)

    The sewage system of Dar es Salaam City, Tanzania, serves only 15% of the population, making sewage one of the leading sources of marine pollution. This study was initiated to assess the potential of peri-urban mangrove forests as filters and phyto-remediators of sewage and the growth of two mangrove species under ...

  11. Growth response, sexual development, carcass and meat quality of ...

    African Journals Online (AJOL)

    Effects of intratesticularly administered zinc tannate (ZT) on growth performance, sexual development, slaughter, carcass and meat quality characteristics of young bull calves (-225 kg, 7 months old) were investigated. Comparisons were made across a three (treatments: ZT animals, intact bulls and burdizzo-castrated.

  12. Growth and Phosphorus Uptake Responses of Bambara Groundnut ...

    African Journals Online (AJOL)

    The effect of arbuscular mycorrhiza on growth and nutrient uptake by bambara groundnut (Vigna subterranea) grown in two acid soils (Basachia series, a Haplustox and Udu series, a Gleyic Luvisol) was investigated in a phytotron. The aim was to determine the extent of infection in the roots of V. subterranea plants by ...

  13. Testosterone, growth hormone and IGF-I responses to acute and chronic resistive exercise in men aged 55-70 years.

    Science.gov (United States)

    Nicklas, B J; Ryan, A J; Treuth, M M; Harman, S M; Blackman, M R; Hurley, B F; Rogers, M A

    1995-10-01

    We investigated the responses of serum testosterone (T) and human growth hormone (hGH) concentrations to a bout of heavy resistive exercise and the responses of T, hGH, and insulin-like growth factor I (IGF-I) to a 16 wk progressive resistive training program in 13 men (60 +/- 4 yrs). Body composition via hydrostatic weighing and muscle strength using a 3 repetition maximum (3RM) test on 6 variable resistance exercise machines were assessed before and after the training program. Fasting blood samples were drawn on 2 consecutive days prior to training and again on 2 consecutive days after the last day of exercise. Blood was also drawn immediately before and approximately 10 min after a single exercise session during the first wk of training, and after an exercise session of the same relative resistance during the last wk of training. The training program resulted in a 37% increase in upper body strength and a 39% increase in lower body strength (both p hGH, and IGF-I were unaffected by the training program. We conclude that an acute bout of resistive exercise causes a substantial hGH response in older men, but 16 wks of progressive resistive training does not affect baseline concentrations of the anabolic hormones.

  14. Growth responses of subalpine fir to climatic variability in the Pacific Northwest

    Science.gov (United States)

    Peterson, D.W.; Peterson, D.L.; Ettl, Gregory J.

    2002-01-01

    We studied regional variation in growth-limiting factors and responses to climatic variability in subalpine forests by analyzing growth patterns for 28 tree-ring growth chronologies from subalpine fir (Abies lasiocarpa (Hook.) Nutt.) stands in the Cascade and Olympic Mountains (Washington and Oregon, U.S.A.). Factor analysis identified four distinct time series of common growth patterns; the dominant growth pattern at any site varied with annual precipitation and temperature (elevation). Throughout much of the region, growth is negatively correlated with winter precipitation and spring snowpack depth, indicating that growth is limited primarily by short growing seasons. On the driest and warmest sites, growth is negatively correlated with previous summer temperature, suggesting that low summer soil moisture limits growth. Growth patterns in two regions were sensitive to climatic variability associated with the Pacific Decadal Oscillation, apparently responding to low-frequency variation in spring snowpack and summer soil moisture (one negatively, one positively). This regional-scale analysis shows that subalpine fir growth in the Cascades and Olympics is limited by different climatic factors in different subregional climates. Climatea??growth relationships are similar to those for a co-occurring species, mountain hemlock (Tsuga mertensiana (Bong.) Carri??re), suggesting broad biogeographic patterns of response to climatic variability and change by subalpine forest ecosystems in the Pacific Northwest.

  15. Growth Responses and Survival of the Goldfish, Carassius auratus ...

    African Journals Online (AJOL)

    Five sets of 20-day old goldfish fry, Carassius auratus with average weights of 0.167 ± 0.003 g were reared for eight weeks in plastic bowls for growth and survival studies. One set (labelled MN) was fed Moina and Cyclops. A second set (labelled FM) was fed fishmeal, and a third set (labelled AF) was fed a 45% protein ...

  16. Growth and nutrient uptake responses of 'Seolhyang' strawberry to ...

    African Journals Online (AJOL)

    The effect of the variation of NH4+:NO3− ratios (meq/l: 0:100, 40:60, 50:50, 65:35 and 100:0) in the nutrient solution on strawberry (Fragaria × ananassa var Seolhyang) growth was evaluated. A mixture of large particle size (2 to 5 mm) and small particle size (smaller than 1 mm) of perlite was used as growing substrate and ...

  17. Growth and yield responses of Sphenostylis stenocarpa (Hochst ex ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-02-18

    Feb 18, 2009 ... The effects of varying levels (0, 110, 220, 330, 440, and 550 kg P/ha) of phosphate application on some growth and yield parameters of African yam bean were studied. Plant dry weight under 550 kg P/ha treated soils with values ranging from 13.79 to 16.32 g per plant significantly (<0.05) differed from ...

  18. Growth performance, carcass response and cost benefit analysis of ...

    African Journals Online (AJOL)

    Growth performance at finisher phase revealed that average live weight was significantly (p<0.05) highest 2.17 kg/bird in birds fed 66.6 % CGM. Weekly weight gain was also significantly (p<0.05) highest 0.86kg/bird among birds placed on 66.6 % CGM. Feed conversion ratio and protein efficiency ratio were also ...

  19. Growth properties and growth factor responsiveness in skin fibroblasts from centenarians.

    Science.gov (United States)

    Tesco, G; Vergelli, M; Grassilli, E; Salomoni, P; Bellesia, E; Sikora, E; Radziszewska, E; Barbieri, D; Latorraca, S; Fagiolo, U; Santacaterina, S; Amaducci, L; Tiozzo, R; Franceschi, C; Sorbi, S

    1998-03-27

    Human fibroblast cultures, which have a finite replicative lifespan in vitro, are the most widely used model for the study of senescence at the cellular level. An inverse relationship between replicative capability and donor age has been reported in human fibroblast strains. We studied the growth capacity of fibroblast primary cultures derived from people whose lifespan was as closer as possible to the expected maximum human lifespan, i.e. people over one hundred. Our data suggest that outgrowth of fibroblasts from biopsies, growth kinetics at different population doubling levels, capability to respond to a classical mitogenic stimulus (such as 20% serum) and a variety of growth factors, were remarkably similar in fibroblasts from centenarians and young controls. On the whole, our data challenge the tenet of a simple and strict relationship between in vivo aging and in vitro proliferative capability of human fibroblasts, at least at the individual level.

  20. Tree growth response of Fokienia hodginsii to recent climate warming and drought in southwest China

    Science.gov (United States)

    Su, Jiajia; Gou, Xiaohua; Deng, Yang; Zhang, Ruibo; Liu, Wenhuo; Zhang, Fen; Lu, Ming; Chen, Yao; Zheng, Wuji

    2017-12-01

    To date, few attempts have been made to assess the influence of climate change on forest ecosystems and on the relationship between tree growth and climate in humid areas of low latitudes. In this paper, we studied the response of tree growth and forest ecosystem to climate change by using Fokienia hodginsii tree-ring cores from the northern Yunnan-Guizhou Plateau, southwest of China. Tree growth correlates the highest ( r = -0.64, p drought. In addition, a large proportion of mature F. hodginsii mortality occurred from 2007 to 2013, which corresponds with a drastic reduction of radial growth (narrowest in recent 100 years). The recent drought, induced by decreasing precipitation and increasing temperature, may have passed the threshold which F. hodginsii could tolerate, causing tree growth reduction, tree growth-climate relationship change, as well as catastrophic tree mortality. All these changes may lead to further responses of the local ecosystem to climate change which should be highly regarded.

  1. Predicting the response to growth hormone treatment in short children with chronic kidney disease.

    Science.gov (United States)

    Mehls, Otto; Lindberg, Anders; Nissel, Richard; Haffner, Dieter; Hokken-Koelega, Anita; Ranke, Michael B

    2010-02-01

    Short stature in children with chronic kidney disease (CKD) is due to various underlying congenital or acquired renal disorders resulting in variable impairment of renal function and variable response to GH treatment. It was the aim to develop a mathematical model that allows the prediction of the individual growth response and to identify nonresponders. Data from 208 prepubertal children on conservative or dialysis treatment in a large pharmaco-epidemiological survey, the KIGS (Pfizer International Growth Database), were used for the model and data from 67 similar CKD patients registered at the Dutch Growth Research Foundation for validation. Annualized height velocity (centimeters per year) during the first year of GH treatment was best predicted by age at start, weight sd score, underlying renal disorder (hereditary kidney disorder), glomerular filtration rate (at baseline), and GH dosage. Using these parameters, the final model explained 37% of the overall variability of growth response. Standard error of the estimates was 1.6 cm. Age was the most important predictor of growth response (20.3% of variability) followed by weight sd score at start, and 27.2% of the variability of the second-year response could be predicted by the first-year response and glomerular filtration rate. Nonresponders of the validation group could be correctly identified. Based on simple clinical variables, a robust prediction model was developed that provides realistic expectations of individual growth response to GH in short children with CKD. The model will help in identifying nonresponders and to tailor treatment strategies.

  2. Growth hormone, prolactin and cortisol response to exercise in patients with depression

    DEFF Research Database (Denmark)

    Krogh, Jesper; Nordentoft, Merete; Mohammad-Nezhad, Mahdi

    2010-01-01

    BACKGROUND: A blunted growth hormone and prolactin response to pharmacological stress test have previously been found in depressed patients, as well as an increased cortisol response to psychosocial stress. This study investigated these hormones in response to acute exercise using an incremental...... bicycle test. METHOD: A cross-sectional comparison of cortisol, growth hormone, and prolactin in depressed (n=137) and healthy (n=44) subjects during rest and in response to an incremental bicycle test. Secondly, we tested the depressed patients again after a 4-month randomized naturalistic exercise...... intervention. RESULTS: Resting plasma levels of growth hormone (GH), cortisol, or prolactin (PRL) did not differ between depressed and healthy subjects (all p-values>.12). In response to an incremental bicycle test the GH (p=.02) and cortisol (p=.05) response in depressed was different compared to healthy...

  3. Uniform shrub growth response to June temperature across the North Slope of Alaska

    Science.gov (United States)

    Ackerman, Daniel E.; Griffin, Daniel; Hobbie, Sarah E.; Popham, Kelly; Jones, Erin; Finlay, Jacques C.

    2018-04-01

    The expansion of woody shrubs in arctic tundra alters many aspects of high-latitude ecosystems, including carbon cycling and wildlife habitat. Dendroecology, the study of annual growth increments in woody plants, has shown promise in revealing how climate and environmental conditions interact with shrub growth to affect these key ecosystem properties. However, a predictive understanding of how shrub growth response to climate varies across the heterogeneous landscape remains elusive. Here we use individual-based mixed effects modeling to analyze 19 624 annual growth ring measurements in the stems of Salix pulchra (Cham.), a rapidly expanding deciduous shrub. Stem samples were collected at six sites throughout the North Slope of Alaska. Sites spanned four landscapes that varied in time since glaciation and hence in soil properties, such as nutrient availability, that we expected would modulate shrub growth response to climate. Ring growth was remarkably coherent among sites and responded positively to mean June temperature. The strength of this climate response varied slightly among glacial landscapes, but in contrast to expectations, this variability was not systematically correlated with landscape age. Additionally, shrubs at all sites exhibited diminishing marginal growth gains in response to increasing temperatures, indicative of alternative growth limiting mechanisms in particularly warm years, such as temperature-induced moisture limitation. Our results reveal a regionally-coherent and robust shrub growth response to early season growing temperature, with local soil properties contributing only a minor influence on shrub growth. Our conclusions strengthen predictions of changes to wildlife habitat and improve the representation of tundra vegetation dynamics in earth systems models in response to future arctic warming.

  4. Differential responses of onion and garlic against plant growth regulators

    International Nuclear Information System (INIS)

    Oozunidou, G.; Asif, M.; Giannakuola, A.; Iliass, A.

    2011-01-01

    The effects of Gibberellic acid-GA3, Prohexadione-Calcium, and Ethephon pre-harvest application on yield, biomass production, photosynthetic function, lipid peroxidation and quality characteristics of onion (Allium cepa L.) and garlic (Allium sativum L.) plants were investigated. Shoot length and biomass of onion and garlic, expressed either in fresh or dry weight, increased significantly under GA3, while a progressive decrease under Prohex-Ca and Ethephon occurred. Higher MDA (lipid peroxidation) values were recorded after Prohex-Ca and Ethephon supply on onion and garlic plants; it seems that GA3 treatment prevents lipid peroxidation as measured with the help of the TBARS method. Plants treated with Prohex-Ca and Ethephon revealed higher peroxidase activity compared to control and GA3 treated plants. Considering the results of MDA content and peroxidase activities it can be assumed that GA3 treated plants are slightly protected from the natural course of oxidative stress, which occurs during ageing as observed for control samples. The fluctuations of chlorophyll fluorescence parameters represent a general decline in chloroplasts function after plant growth regulators exposure, whereas in combination to the suppressed chlorophyll content, structural malformations of photo systems may also occur. The production of ascorbic acid, glucose and fructose content seems to be enhanced under GA3 in both species, while their values were depressed under Prohex-Ca and Ethephon. Overall, only GA3 supply leads to a vigorous onion and garlic growth and yield. (author)

  5. Growth and Physiological Responses of Phaseolus Species to Salinity Stress

    Directory of Open Access Journals (Sweden)

    J. S. Bayuelo-Jiménez

    2012-01-01

    Full Text Available This paper reports the changes on growth, photosynthesis, water relations, soluble carbohydrate, and ion accumulation, for two salt-tolerant and two salt-sensitive Phaseolus species grown under increasing salinity (0, 60 and 90 mM NaCl. After 20 days exposure to salt, biomass was reduced in all species to a similar extent (about 56%, with the effect of salinity on relative growth rate (RGR confined largely to the first week. RGR of salt-tolerant species was reduced by salinity due to leaf area ratio (LAR reduction rather than a decline in photosynthetic capacity, whereas unit leaf rate and LAR were the key factors in determining RGR on salt-sensitive species. Photosynthetic rate and stomatal conductance decreased gradually with salinity, showing significant reductions only in salt-sensitive species at the highest salt level. There was little difference between species in the effect of salinity on water relations, as indicated by their positive turgor. Osmotic adjustment occurred in all species and depended on higher K+, Na+, and Cl− accumulation. Despite some changes in soluble carbohydrate accumulation induced by salt stress, no consistent contributions in osmotic adjustment could be found in this study. Therefore, we suggest that tolerance to salt stress is largely unrelated to carbohydrate accumulation in Phaseolus species.

  6. Growth response, water relations and K/Na ratio in wheat under ...

    African Journals Online (AJOL)

    Growth response, water relations and K/Na ratio in wheat under sodium and calcium interactions. BH Niazi, B Zaman, M Salim, H Athar. Abstract. A study was conducted in the glass house to observe the role of K/Na ratio and moisture contents on the growth of wheat (Triticum aestivum L .cv. Lu-26) under NaCl stress.

  7. Growth and development response of maize ( Zea mays L. ) In crude ...

    African Journals Online (AJOL)

    Growth and development response of Zea mays were investigated at the University of Port Harcourt botanical garden. Crude oil pollution effects of direct spray on foliage or spill on soil on the growth changes and chlorophyll content of Z. mays were examined, alongside a control. There were significant (p = 0.05) reductions ...

  8. Growth Response of Explants of Irvingia Gabonensis (O'rorke, Baill ...

    African Journals Online (AJOL)

    Growth response of explants of Irvingia gabonensis to in vitro treatment was investigated using full, half and one quarter strength mineral components based on Murashige and Skoog medium. Plant growth regulator (kinetin-Kin) with concentration levels of 0, 1, 2, 3, 4 and 5mg/l were used for shoots initiation, while axillary ...

  9. Loblolly pine growth response to mid-rotational treatments in an Eastern Texas plantation

    Science.gov (United States)

    Mohammad M. Bataineh; Amanda L. Bataineh; Brian P. Oswald; Kenneth W. Farrish; Hans M. Williams

    2006-01-01

    The effects of mid-rotational treatments (herbicide, prescribed burn, combination of herbicide and burn, and fertilization) on growth of loblolly pine were evaluated. Five replicates were established in a split-plot experimental design with fertilizer treatments as the whole-plot factor and competition control treatments as the sub-plot factor. Growth response was...

  10. Solanum cultivar responses to arbuscular mycorrhizal fungi: growth ...

    African Journals Online (AJOL)

    A greenhouse experiment was carried out in a sandy soil with a low available phosphorus to evaluate responsiveness of four Solanum aethiopicum cultivars to indigenous arbuscular mycorrhizal fungi. Results showed clear interaction between genetic variability of cultivars and fungal isolates on shoot biomass and on ...

  11. Whitebark pine diameter growth response to removal of competition

    Science.gov (United States)

    Robert E. Keane; Kathy L. Gray; Laura J. Dickinson

    2007-01-01

    Silvicultural cutting treatments may be needed to restore whitebark pine (Pinus albicaulis) forests, but little is known of the response of this species to removal of competition through prescribed burning or silvicultural cuttings. We analyzed stem cross-sections from 48 whitebark pine trees in Montana around which most of the competing vegetation...

  12. Growth hormone, prolactin and cortisol response to exercise in patients with depression

    DEFF Research Database (Denmark)

    Krogh, Jesper; Nordentoft, Merete; Mohammad-Nezhad, Mahdi

    2010-01-01

    controls. The effect of acute exercise stress on PRL (p=.56) did not differ between depressed and healthy subjects. Apart from a decrease in GH response in the strength-training group (p=.03) the pragmatic exercise intervention did not affect resting hormonal levels, or the response to acute exercise....... CONCLUSIONS: Patients with mild to moderate depression had a different growth hormone and cortisol response to acute exercise stress compared to healthy controls. Strength training was able to reduce the growth hormone response to acute exercise stress in this patient population. Studies with more rigorous...

  13. Modeling lodgepole pine radial growth relative to climate and genetics using universal growth-trend response functions.

    Science.gov (United States)

    McLane, Sierra C; LeMay, Valerie M; Aitken, Sally N

    2011-04-01

    Forests strongly affect Earth's carbon cycles, making our ability to forecast forest-productivity changes associated with rising temperatures and changes in precipitation increasingly critical. In this study, we model the influence of climate on annual radial growth using lodgepole pine (Pinus contorta) trees grown for 34 years in a large provenance experiment in western Canada. We use a random-coefficient modeling approach to build universal growth-trend response functions that simultaneously incorporate the impacts of different provenance and site climates on radial growth trends under present and future annual (growth-year), summer, and winter climate regimes. This approach provides new depth to traditional quantitative genetics population response functions by illustrating potential changes in population dominance over time, as well as indicating the age and size at which annual growth begins declining for any population growing in any location under any present or future climate scenario within reason, given the ages and climatic conditions sampled. Our models indicate that lodgepole pine radial-growth levels maximize between 3.9 degrees and 5.1 degrees C mean growth-year temperature. This translates to productivity declining by the mid-21st century in southern and central British Columbia (BC), while increasing beyond the 2080s in northern BC and Yukon, as temperatures rise. Relative to summer climate indices, productivity is predicted to decline continuously through the 2080s in all locations, while relative to winter climate variables, the opposite trend occurs, with the growth increases caused by warmer winters potentially offsetting the summer losses. Trees from warmer provenances, i.e., from the center of the species range, perform best in nearly all of our present and future climate-scenario models. We recommend that similar models be used to analyze population growth trends relative to annual and intra-annual climate in other large-scale provenance

  14. Height velocity targets from the national cooperative growth study for first-year growth hormone responses in short children.

    Science.gov (United States)

    Bakker, Bert; Frane, James; Anhalt, Henry; Lippe, Barbara; Rosenfeld, Ron G

    2008-02-01

    Although GH has been used to treat short stature in GH deficiency (GHD) and other conditions for more than 40 yr, criteria for satisfactorily defining targets for GH responsiveness have never been developed. The objective of this study was to present the first-year growth expressed as height velocity (HV) for prepubertal boys and girls with idiopathic GHD, organic GHD, idiopathic short stature, or Turner syndrome from Genentech's National Cooperative Growth Study to derive age-specific targets for GH responsiveness for each etiology and gender. Using data from the National Cooperative Growth Study, we constructed curves of response to GH during the first year of treatment with standard daily doses in naive-to-treatment prepubertal children with idiopathic GHD (2323 males, 842 females), organic GHD (582 males, 387 females), idiopathic short stature (1392 males, 465 females), or Turner syndrome (1367 females). For each category, mean pretreatment and mean +/-1 and +/-2 sd for the first-year HV on GH were assessed. Mean and mean +/- 1 sd for HV were plotted vs. age at baseline (initiation of GH treatment) and compared with mean pretreatment HV. HV plots for each category as a factor of age at baseline are presented. Mean - 2 sd HV plots approximated the pretreatment HV. Using baseline age- and gender-specific targets will assist clinicians in assessing a patient's first-year growth response. We propose that HV below the mean - 1 sd on these plots be considered a "poor" response. These curves may be used to identify patients who may benefit from GH dose adjustment, to assess compliance issues, or to challenge the original diagnosis.

  15. Growth hormone secretion and response to growth hormone therapy after treatment for brain tumour

    International Nuclear Information System (INIS)

    Lannering, B.; Marky, I.; Mellander, L.; Albertson-Wikland, K.

    1988-01-01

    Children irradiated for brain tumours constitute an increasing group of patients who will require GH therapy. High-dose cranial irradiation is necessary for cure, but inevitably causes GH deficiency within a few years. In 19 patients investigated between 2 and 9 years after irradiation, the spontaneous 24-hour GH secretion was markedly reduced. The secretory pattern indicated loss of regulating hypothalamic hormones. After exogenous GHRH was administered, the pituitary was able to respond with a prompt GH release, showing that pituitary function was unaffected. Ten prepubertal children growing 3.8+-0.3 cm/year were treated with GH, 0.1 IU/kg/day s.c. Their growth rate increased to 8.2+-0.4 cm in the first year. An increased growth rate was also maintained in the second year. (authors)

  16. Differential growth stimulation response of potato towards inoculation with taxonomically diverse plant growth promoting rhizobacteria

    OpenAIRE

    Tahir eNaqqash; Sohail eHameed; Asma eImran; Muhammad Kashif Hanif; Afshan eMajeed; Afshan eMajeed; Jan Dirk eVan Elsas

    2016-01-01

    Rhizosphere engineering with beneficial plant growth promoting bacteria offers great promise for sustainable crop yield. Potato is an important food commodity that needs large inputs of nitrogen and phosphorus fertilizers. To overcome high fertilizer demand (especially nitrogen), five bacteria, i.e. Azospirillum sp.TN10, Agrobacterium sp.TN14, Pseudomonas sp.TN36, Enterobactersp. TN38 and Rhizobium sp. TN42 were isolated from the potato rhizosphere on nitrogen-free malate medium and identifie...

  17. Growth responses, biomass partitioning, and nitrogen isotopes of prairie legumes in response to elevated temperature and varying nitrogen source in a growth chamber experiment.

    Science.gov (United States)

    Whittington, Heather R; Deede, Laura; Powers, Jennifer S

    2012-05-01

    Because legumes can add nitrogen (N) to ecosystems through symbiotic fixation, they play important roles in many plant communities, such as prairies and grasslands. However, very little research has examined the effect of projected climate change on legume growth and function. Our goal was to study the effects of temperature on growth, nodulation, and N chemistry of prairie legumes and determine whether these effects are mediated by source of N. We grew seedlings of Amorpha canescens, Dalea purpurea, Lespedeza capitata, and Lupinus perennis at 25/20°C (day/night) or 28/23°C with and without rhizobia and mineral N in controlled-environment growth chambers. Biomass, leaf area, nodule number and mass, and shoot N concentration and δ(15)N values were measured after 12 wk of growth. Both temperature and N-source affected responses in a species-specific manner. Lespedeza showed increased growth and higher shoot N content at 28°C. Lupinus showed decreases in nodulation and lower shoot N concentration at 28°C. The effect of temperature on shoot N concentration occurred only in individuals whose sole N source was N(2)-fixation, but there was no effect of temperature on δ(15)N values in these plants. Elevated temperature enhanced seedling growth of some species, while inhibiting nodulation in another. Temperature-induced shifts in legume composition or nitrogen dynamics may be another potential mechanism through which climate change affects unmanaged ecosystems.

  18. Disease resistance or growth: the role of plant hormones in balancing immune responses and fitness costs

    NARCIS (Netherlands)

    Denance, N.; Sanchez Vallet, A.; Goffner, D.; Molina, A.

    2013-01-01

    Plant growth and response to environmental cues are largely governed by phytohormones. The plant hormones ethylene, jasmonic acid, and salicylic acid (SA) play a central role in the regulation of plant immune responses. In addition, other plant hormones, such as auxins, abscisic acid (ABA),

  19. The effect of the synthetic oviductal fluid medium (SOF supplemented with insulin-like growth factor-I (IGF-I on in vitro maturation of canine oocytes (Canis familiaris/ Influência do fator de crescimento semelhante à insulina I (IGF-I adicionado ao meio fluido sintético de tuba uterina (SOF sobre a maturação in vitro de oócitos caninos (Canis familiaris

    Directory of Open Access Journals (Sweden)

    Kellen Oliveira

    2007-08-01

    Full Text Available The follicular growth and oocyte maturation knowledge are very important to the development and improvement ofnew biotechnologies such as in vitro fertilization and somatic cell nuclear transfer. In order to the necessity of clarifythe basic mechanisms related to canine oocyte maturation, this investigation focuses on the evaluation of the effectof insulin-like growth factor-i (IGF-I, added to synthetic oviductal fluid medium (SOF on the in vitro maturation ofdomestic dog oocytes. Thirty-seven bitches undergoing ovariohysterectomy for castration or due to pathologicalconditions of the uterus were selected as oocytes’ donors (n=875. The oocytes were allocated in the followinggroups: M0 (stained in the collection’s time, Control (72h in SOF and Experimental (72h in SOF plus 100 ng IGF-I.After 72 hours of maturation the oocytes’ nuclear status were assessed by Hoechst 33342 dye. The best results interms of oocyte harvest were observed in those juvenile donors, females in estrus, nuliparous and pure breeds. Nosignificant differences were observed between treatments control (SOF or experimental (IGF-I.O conhecimento da regulação do crescimento folicular e da maturação oocitária é de grande importância no desenvolvimento e aperfeiçoamento de novas biotecnologias como a fecundação in vitro e a transferência nuclear. Considerando-se a necessidade de elucidação dos mecanismos básicos envolvidos na maturação oocitária na espécie canina, a presente pesquisa foi desenvolvida com o objetivo de avaliar o efeito do fator de crescimento semelhante à insulina-I (IGF-I, adicionado ao meio fluido sintético de tuba uterina (SOF, sobre a maturação de oócitos caninos. Foram utilizadas 37 cadelas submetidas à ovariohisterectomia, eletivas e terapêuticas, como doadoras dos complexos cumulus oócitos grau 1 (n=875 que foram alocados em três grupos: M0 (coloração no momento da colheita, Controle (72 h no meio SOF e Experimental (72h no

  20. Corporate Social Responsibility and Environmentally Sound Technology in Endogenous Firm Growth

    Directory of Open Access Journals (Sweden)

    Angela C. Chao

    2017-02-01

    Full Text Available We have entered the “New Normal” economy, with more emphasis on economic growth driven by innovation than resource. This paper investigates the impacts of firms considering corporate social responsibility and environmentally sound technology by building a three-stage Cournot competition model with asymmetric cost. The sustainable development of economic and endogenous firm growth achieves the win–win result in the theoretical model. Using data from 31 firms in China, this paper empirically researches on the relationships among corporate social responsibility, environmentally sound technology and firm endogenous growth. The results show that: (1 Marginal cost decreased with the increase of innovation, as well as getting government research and development subsidy, which has a positive effect on firm growth. (2 Consumers respond positively to corporate social responsibility initiative, the reputation of the firm can be improved. At the same time, environmentally sound technology objectively reduces the marginal cost of competitors because of the technology spillover. (3 Profit of a firm undertaking corporate social responsibility partly decreases, which has a negative effect on firm growth. The contradiction between corporate social responsibility and profit of firm could be adjusted, such as socially responsible investment fund hosed by institutional investors.

  1. Growth Response From Herbicide, Prescribed Fire, and Fertilizer Treatments in Midrotational Loblolly Pine: Fire-Year Response

    Science.gov (United States)

    Mary Michelle Barnett; Sandra Rideout; Brian P. Oswald; Kenneth W. Farrish; Hans M. Williams

    2002-01-01

    This study was initiated to determine growth response resulting from the application of prescribed fire and herbicide, with and without fertilization. In southeast Texas, herbicide, prescribed fire and fertilizer treatments were applied in mid-rotational loblolly pine plantations 1.5 years after thinning. Five replications were established at each of two study sites...

  2. Cancer drug troglitazone stimulates the growth and response of renal cells to hypoxia inducible factors

    International Nuclear Information System (INIS)

    Taub, Mary

    2016-01-01

    Troglitazone has been used to suppress the growth of a number of tumors through apoptosis and autophagy. However, previous in vitro studies have employed very high concentrations of troglitazone (≥10 −5  M) in order to elicit growth inhibitory effects. In this report, when employing lower concentrations of troglitazone in defined medium, troglitazone was observed to stimulate the growth of primary renal proximal tubule (RPT) cells. Rosiglitazone, like troglitazone, is a thiazolidinedione (TZD) that is known to activate Peroxisome Proliferator Activated Receptor Υ (PPARΥ). Notably, rosiglitazone also stimulates RPT cell growth, as does Υ-linolenic acids, another PPARΥ agonist. The PPARΥ antagonist GW9662 inhibited the growth stimulatory effect of troglitazone. In addition, troglitazone stimulated transcription by a PPAR Response Element/Luciferase construct. These results are consistent with the involvement of PPARΥ as a mediator of the growth stimulatory effect of troglitazone. In a number of tumor cells, the expression of hypoxia inducible factor (HIF) is increased, promoting the expression of HIF inducible genes, and vascularization. Troglitazone was observed to stimulate transcription by a HIF/luciferase construct. These observations indicate that troglitazone not only promotes growth, also the survival of RPT cells under conditions of hypoxia. - Highlights: • Troglitazone and rosiglitazone stimulate renal proximal tubule cell growth. • Troglitazone and linolenic acid stimulate growth via PPARϒ. • Linolenic acid stimulates growth in the presence of fatty acid free serum albumin. • Rosiglitazone stimulates transcription by a HRE luciferase construct.

  3. Cancer drug troglitazone stimulates the growth and response of renal cells to hypoxia inducible factors

    Energy Technology Data Exchange (ETDEWEB)

    Taub, Mary, E-mail: biochtau@buffalo.edu

    2016-03-11

    Troglitazone has been used to suppress the growth of a number of tumors through apoptosis and autophagy. However, previous in vitro studies have employed very high concentrations of troglitazone (≥10{sup −5} M) in order to elicit growth inhibitory effects. In this report, when employing lower concentrations of troglitazone in defined medium, troglitazone was observed to stimulate the growth of primary renal proximal tubule (RPT) cells. Rosiglitazone, like troglitazone, is a thiazolidinedione (TZD) that is known to activate Peroxisome Proliferator Activated Receptor Υ (PPARΥ). Notably, rosiglitazone also stimulates RPT cell growth, as does Υ-linolenic acids, another PPARΥ agonist. The PPARΥ antagonist GW9662 inhibited the growth stimulatory effect of troglitazone. In addition, troglitazone stimulated transcription by a PPAR Response Element/Luciferase construct. These results are consistent with the involvement of PPARΥ as a mediator of the growth stimulatory effect of troglitazone. In a number of tumor cells, the expression of hypoxia inducible factor (HIF) is increased, promoting the expression of HIF inducible genes, and vascularization. Troglitazone was observed to stimulate transcription by a HIF/luciferase construct. These observations indicate that troglitazone not only promotes growth, also the survival of RPT cells under conditions of hypoxia. - Highlights: • Troglitazone and rosiglitazone stimulate renal proximal tubule cell growth. • Troglitazone and linolenic acid stimulate growth via PPARϒ. • Linolenic acid stimulates growth in the presence of fatty acid free serum albumin. • Rosiglitazone stimulates transcription by a HRE luciferase construct.

  4. Declining Radial Growth Response of Coastal Forests to Hurricanes and Nor'easters

    Science.gov (United States)

    Fernandes, Arnold; Rollinson, Christine R.; Kearney, William S.; Dietze, Michael C.; Fagherazzi, Sergio

    2018-03-01

    The Mid-Atlantic coastal forests in Virginia are stressed by episodic disturbance from hurricanes and nor'easters. Using annual tree ring data, we adopt a dendroclimatic and statistical modeling approach to understand the response and resilience of a coastal pine forest to extreme storm events, over the past few decades. Results indicate that radial growth of trees in the study area is influenced by age, regional climate trends, and individual tree effects but dominated periodically by growth disturbance due to storms. We evaluated seven local extreme storm events to understand the effect of nor'easters and hurricanes on radial growth. A general decline in radial growth was observed in the year of the extreme storm and 3 years following it, after which the radial growth started recovering. The decline in radial growth showed a statistically significant correlation with the magnitude of the extreme storm (storm surge height and wind speed). This study contributes to understanding declining tree growth response and resilience of coastal forests to past disturbances. Given the potential increase in hurricanes and storm surge severity in the region, this can help predict vegetation response patterns to similar disturbances in the future.

  5. Growth hormone responsiveness: peak stimulated growth hormone levels and other variables in idiopathic short stature (ISS): data from the National Cooperative Growth Study.

    Science.gov (United States)

    Moore, Wayne V; Dana, Ken; Frane, James; Lippe, Barbara

    2008-09-01

    In children with idiopathic short stature (ISS), growth hormone (GH) response to a provocative test will be inversely related to the first year response to hGH and be a variable accounting for a degree of responsiveness. Because high levels of GH are a characteristic of GH insensitivity, such as in Laron syndrome, it is possible that a high stimulated GH is associated with a lower first year height velocity among children diagnosed as having ISS. We examined the relationship between the peak stimulated GH levels in 3 ISS groups; GH >10 -40 ng/mL and the first year growth response to rhGH therapy. We also looked at 8 other predictor variables (age, sex, height SDS, height age, body mass index (BMI), bone age, dose, and SDS deficit from target parental height. Multiple regression analysis with the first year height as the dependent variable and peak stimulated GH was the primary endpoint. The predictive value of adding each of the other variables was then assessed. Mean change in height velocity was similar among the three groups, with a maximum difference among the groups of 0.6 cm/yr. There was a small but statistically significant correlation (r=-0.12) between the stimulated GH and first year height velocity. The small correlation between first year growth response and peak GH is not clinically relevant in defining GH resistance. No cut off level by peak GH could be determined to enhance the usefulness of this measure to predict response. Baseline age was the only clinically significant predictor, R-squared, 6.4%. All other variables contributed less than an additional 2% to the R-squared.

  6. Regression analysis of growth responses to water depth in three wetland plant species

    DEFF Research Database (Denmark)

    Sorrell, Brian K; Tanner, Chris C; Brix, Hans

    2012-01-01

    ) differing in depth preferences in wetlands, using non-linear and quantile regression analyses to establish how flooding tolerance can explain field zonation. Methodology Plants were established for 8 months in outdoor cultures in waterlogged soil without standing water, and then randomly allocated to water...... depths from 0 – 0.5 m. Morphological and growth responses to depth were followed for 54 days before harvest, and then analysed by repeated measures analysis of covariance, and non-linear and quantile regression analysis (QRA), to compare flooding tolerances. Principal results Growth responses to depth...... differed between the three species, and were non-linear. P. tenax growth rapidly decreased in standing water > 0.25 m depth, C. secta growth increased initially with depth but then decreased at depths > 0.30 m, accompanied by increased shoot height and decreased shoot density, and T. orientalis...

  7. Predicting the Probability of Abnormal Stimulated Growth Hormone Response in Children After Radiotherapy for Brain Tumors

    Energy Technology Data Exchange (ETDEWEB)

    Hua Chiaho, E-mail: Chia-Ho.Hua@stjude.org [Department of Radiological Sciences, St. Jude Children' s Research Hospital, Memphis, Tennessee (United States); Wu Shengjie [Department of Biostatistics, St. Jude Children' s Research Hospital, Memphis, Tennessee (United States); Chemaitilly, Wassim [Division of Endocrinology, Department of Pediatric Medicine, St. Jude Children' s Research Hospital, Memphis, Tennessee (United States); Lukose, Renin C.; Merchant, Thomas E. [Department of Radiological Sciences, St. Jude Children' s Research Hospital, Memphis, Tennessee (United States)

    2012-11-15

    Purpose: To develop a mathematical model utilizing more readily available measures than stimulation tests that identifies brain tumor survivors with high likelihood of abnormal growth hormone secretion after radiotherapy (RT), to avoid late recognition and a consequent delay in growth hormone replacement therapy. Methods and Materials: We analyzed 191 prospectively collected post-RT evaluations of peak growth hormone level (arginine tolerance/levodopa stimulation test), serum insulin-like growth factor 1 (IGF-1), IGF-binding protein 3, height, weight, growth velocity, and body mass index in 106 children and adolescents treated for ependymoma (n = 72), low-grade glioma (n = 28) or craniopharyngioma (n = 6), who had normal growth hormone levels before RT. Normal level in this study was defined as the peak growth hormone response to the stimulation test {>=}7 ng/mL. Results: Independent predictor variables identified by multivariate logistic regression with high statistical significance (p < 0.0001) included IGF-1 z score, weight z score, and hypothalamic dose. The developed predictive model demonstrated a strong discriminatory power with an area under the receiver operating characteristic curve of 0.883. At a potential cutoff point of probability of 0.3 the sensitivity was 80% and specificity 78%. Conclusions: Without unpleasant and expensive frequent stimulation tests, our model provides a quantitative approach to closely follow the growth hormone secretory capacity of brain tumor survivors. It allows identification of high-risk children for subsequent confirmatory tests and in-depth workup for diagnosis of growth hormone deficiency.

  8. Predicting the Probability of Abnormal Stimulated Growth Hormone Response in Children After Radiotherapy for Brain Tumors

    International Nuclear Information System (INIS)

    Hua Chiaho; Wu Shengjie; Chemaitilly, Wassim; Lukose, Renin C.; Merchant, Thomas E.

    2012-01-01

    Purpose: To develop a mathematical model utilizing more readily available measures than stimulation tests that identifies brain tumor survivors with high likelihood of abnormal growth hormone secretion after radiotherapy (RT), to avoid late recognition and a consequent delay in growth hormone replacement therapy. Methods and Materials: We analyzed 191 prospectively collected post-RT evaluations of peak growth hormone level (arginine tolerance/levodopa stimulation test), serum insulin-like growth factor 1 (IGF-1), IGF-binding protein 3, height, weight, growth velocity, and body mass index in 106 children and adolescents treated for ependymoma (n = 72), low-grade glioma (n = 28) or craniopharyngioma (n = 6), who had normal growth hormone levels before RT. Normal level in this study was defined as the peak growth hormone response to the stimulation test ≥7 ng/mL. Results: Independent predictor variables identified by multivariate logistic regression with high statistical significance (p < 0.0001) included IGF-1 z score, weight z score, and hypothalamic dose. The developed predictive model demonstrated a strong discriminatory power with an area under the receiver operating characteristic curve of 0.883. At a potential cutoff point of probability of 0.3 the sensitivity was 80% and specificity 78%. Conclusions: Without unpleasant and expensive frequent stimulation tests, our model provides a quantitative approach to closely follow the growth hormone secretory capacity of brain tumor survivors. It allows identification of high-risk children for subsequent confirmatory tests and in-depth workup for diagnosis of growth hormone deficiency.

  9. Growth temperature exerts differential physiological and transcriptional responses in laboratory and wine strains of Saccharomyces cerevisiae

    DEFF Research Database (Denmark)

    Pizarra, Francisco J.; Jewett, Michael Christopher; Nielsen, Jens

    2008-01-01

    exhibited higher fermentation rates. To elucidate mechanistic differences controlling the growth temperature response and underlying adaptive mechanisms between the strains, DNA microarrays and targeted metabolome analysis were used. We identified 1,007 temperature-dependent genes and 473 strain......-dependent genes. The transcriptional response was used to identify highly correlated gene expression subnetworks within yeast metabolism. We showed that temperature differences most strongly affect nitrogen metabolism and the heat shock response. A lack of stress response element-mediated gene induction, coupled...... environmental conditions and the organoleptic properties that they confer to wine. Here, we used a two-factor design to study the responses of a standard laboratory strain, CEN.PK113-7D, and an industrial wine yeast strain, EC1118, to growth temperatures of 15 degrees C and 30 degrees C in nitrogen...

  10. Growth, uniformity, local responsiveness, and system-wide adaptation in multiunit franchising

    OpenAIRE

    Boulay, Jacques; Caemmerer, Barbara; Evanschitzky, Heiner; Duniach, Krista

    2016-01-01

    Using the resource-based view framework, we investigate the link between multiunit franchising (MUF) and performance on four key challenges in franchise chain management: growth, uniformity, local responsiveness, and system-wide adaptation. Our findings support the assertion that system growth is positively related to MUF rate within a system, in particular in relation to geographic expansion. Interestingly, while uniformity does not seem to be related to MUF rate, we find marginal support fo...

  11. Modeling non-linear growth responses to temperature and hydrology in wetland trees

    Science.gov (United States)

    Keim, R.; Allen, S. T.

    2016-12-01

    Growth responses of wetland trees to flooding and climate variations are difficult to model because they depend on multiple, apparently interacting factors, but are a critical link in hydrological control of wetland carbon budgets. To more generally understand tree growth to hydrological forcing, we modeled non-linear responses of tree ring growth to flooding and climate at sub-annual time steps, using Vaganov-Shashkin response functions. We calibrated the model to six baldcypress tree-ring chronologies from two hydrologically distinct sites in southern Louisiana, and tested several hypotheses of plasticity in wetlands tree responses to interacting environmental variables. The model outperformed traditional multiple linear regression. More importantly, optimized response parameters were generally similar among sites with varying hydrological conditions, suggesting generality to the functions. Model forms that included interacting responses to multiple forcing factors were more effective than were single response functions, indicating the principle of a single limiting factor is not correct in wetlands and both climatic and hydrological variables must be considered in predicting responses to hydrological or climate change.

  12. Studies on the effects on growth and antioxidant responses of two marine microalgal species to uniconazole

    Science.gov (United States)

    Mei, Xueqiao; Zheng, Kang; Wang, Lingdong; Li, Yantuan

    2014-10-01

    Uniconazole, as a plant growth retardant, can enhance stress tolerance in plants, possibly because of improved antioxidation defense mechanisms with higher activities of superoxide dismutase (SOD) and peroxidase (POD) enzymes that retard lipid peroxidation and membrane deterioration. These years much attention has been focused on the responses of antioxidant system in plants to uniconazole stress, but such studies on aquatic organism are very few. Moreover, no information is available on growth and antioxidant response in marine microalgae to uniconazole. In this paper, the growth and antioxidant responses of two marine microalgal species, Platymonas helgolandica and Pavlova viridis, at six uniconazole concentrations (0-15 mg L-1) were investigated. The results demonstrated that 3 mg L-1 uniconazole could increase significantly chlorophyll a and carbohydrate contents of P. helgolandica ( P catalase (CAT) were enhanced remarkably at low concentrations of uniconazole. However, significant reduction of SOD and CAT activities was observed at higher concentrations of uniconazole.

  13. Modulation of the growth and metabolic response of cyanobacteria by the multifaceted activity of naringenin.

    Directory of Open Access Journals (Sweden)

    Beata Żyszka

    Full Text Available The interactions between the plant-derived bioflavonoid, naringenin, and prokaryotic microalgae representatives (cyanobacteria, were investigated with respect to its influence on the growth and metabolic response of these microorganisms. To achieve reliable results, the growth of cyanobacteria was determined based on measurements of chlorophyll content, morphological changes were assessed through microscopic observations, and the chemical response of cells was determined using liquid and gas chromatography (HPLC; GC-FID. The results show that micromolar levels of naringenin stimulated the growth of cyanobacteria. Increased growth was observed for halophilic strains at naringenin concentrations below 40 mg L-1, and in freshwater strains at concentrations below 20 mg L-1. The most remarkable stimulation was observed for the freshwater species Nostoc muscorum, which had a growth rate that was up to 60% higher than in the control. When naringenin was examined at concentrations above 40 mg L-1, the growth of the tested microorganisms was inhibited. Simultaneously, an intensive excretion of exopolysaccharides was observed. Microscopic observations strongly suggest that these effects resulted from a structural disturbance of cyanobacterial cell walls that was exerted by naringenin. This phenomenon, in combination with the absorption of naringenin into cell wall structures, influenced cell permeability and thus the growth of bacteria. Fortunately, almost all the naringenin added to the culture was incorporated into to cell substructures and could be recovered through extraction, raising the possibility that this modulator could be recycled.

  14. Using Remote Sensing Mapping and Growth Response to Environmental Variability to Aide Aquatic Invasive Plant Management

    Science.gov (United States)

    Bubenheim, David L.; Schlick, Greg; Genovese, Vanessa; Wilson, Kenneth D.

    2018-01-01

    Management of aquatic weeds in complex watersheds and river systems present many challenges to assessment, planning and implementation of management practices for floating and submerged aquatic invasive plants. The Delta Region Areawide Aquatic Weed Project (DRAAWP), a USDA sponsored area-wide project, is working to enhance planning, decision-making and operational efficiency in the California Sacramento-San Joaquin Delta. Satellite and airborne remote sensing are used map (area coverage and biomass density), direct operations, and assess management impacts on plant communities. Archived satellite records enable review of results following previous climate and management events and aide in developing long-term strategies. Examples of remote sensing aiding effectiveness of aquatic weed management will be discussed as well as areas for potential technological improvement. Modeling at local and watershed scales using the SWAT modeling tool provides insight into land-use effects on water quality (described by Zhang in same Symposium). Controlled environment growth studies have been conducted to quantify the growth response of invasive aquatic plants to water quality and other environmental factors. Environmental variability occurs across a range of time scales from long-term climate and seasonal trends to short-term water flow mediated variations. Response time for invasive species response are examined at time scales of weeks, day, and hours using a combination of study duration and growth assessment techniques to assess water quality, temperature (air and water), nitrogen, phosphorus, and light effects. These provide response parameters for plant growth models in response to the variation and interact with management and economic models associated with aquatic weed management. Plant growth models are to be informed by remote sensing and applied spatially across the Delta to balance location and type of aquatic plant, growth response to altered environments and

  15. Effects of growth hormone-releasing factor on growth hormone response, growth and feed conversion efficiency in buffalo heifers (Bubalus bubalis).

    Science.gov (United States)

    Haldar, A; Prakash, B S

    2007-09-01

    The aim of this study was to determine the benefits of growth hormone-releasing factor (GRF) on growth and feed conversion efficiency (FCE) in buffaloes. Twelve Murrah buffalo heifers (Bubalus bubalis) of mean age 24.8 months and mean body weight 302.4kg were divided into two groups (treatment and control) with six animals in each group. The buffaloes were given intravenous injections of bovine GRF (bGRF) at a dose rate of 10microg/100kg body weight or an equal volume of saline at 15-day intervals for a period of 9 months. Plasma growth hormone (GH) responses to bGRF challenge were measured in blood samples collected at 90-day intervals on days 1, 90, 180 and 270 and samples were taken at -60, -30, 0, +10, +20, +30, +60, +120 and +180min relative to bGRF injection. Blood samples were also collected weekly by jugular venepuncture for the quantification of plasma GH. The average growth rate (AGR) and FCE of all animals were recorded at 15-day intervals. Plasma GH concentrations increased (P=0.001) steadily following bGRF challenge, peaking 10-20min after challenge and declining to baseline by 180min. In the treatment group, there were no significant differences (P>0.05) in either the peak heights of the GH response or the area under the curve (AUC) of the GH response after bGRF challenge on any of the four occasions of intensive bleeding. There were overall increases in plasma GH concentrations (Pgrowth rates and better feed conversion efficiency in buffalo heifers.

  16. Chronic baclofen therapy improves the blunted growth hormone response to intravenous arginine in subjects with spinal cord injury.

    Science.gov (United States)

    Bauman, W A; Spungen, A M; Zhong, Y G; Tsitouras, P D

    1994-05-01

    Human GH (hGH) secretion is stimulated by vigorous physical activity, whereas immobilization reduces its release. In paralyzed subjects with spinal cord injury (SCI), it has recently been shown that the release of hGH to provocative stimulation and plasma insulin-like growth factor-I (IGF-I) levels are reduced. The acute administration of baclofen, a gamma-aminobutyric acid derivative, has been shown to stimulate hGH release. The present study investigated the effect of chronic administration of baclofen on the provocative testing of hGH secretion and plasma IGF-I levels. Sixteen subjects with SCI were studied; eight subjects were treated (40-80 mg/day; > 6 months) with baclofen (Bac+), and eight were not (Bac-). Additionally, 8 non-SCI subjects were studied as controls. The groups were matched for gender and age. The subjects were not receiving any medications known to influence hGH secretion. After an overnight fast, arginine hydrochloride (30 g/subject) was infused iv over 30 min, with blood drawn for hormone determinations at baseline and 30, 60, 90, and 120 min. In the Bac- group compared with the Bac+ group, the arginine-stimulated mean plasma hGH levels at 30 and 60 min (P hGH levels (P hGH response between the Bac+ group and the control group. Plasma IGF-I levels may reflect the integrated tissue response to hGH. A significant inverse relationship was present between age and plasma IGF-I levels for the control and Bac+ groups, but not for the Bac- group. The mean plasma IGF-I level was significantly reduced in the Bac- compared with the Bac+ group. No significant differences in mean plasma IGF-I levels were noted between the Bac+ and control groups. SCI is associated with body composition changes and metabolic alterations that may be exacerbated by reduced activity of the hGH-IGF-I axis. Oral chronic baclofen therapy appears to reverse the deleterious effects of paralysis and immobilization on hGH physiology.

  17. Reciprocal Regulation of the TOR Kinase and ABA Receptor Balances Plant Growth and Stress Response.

    Science.gov (United States)

    Wang, Pengcheng; Zhao, Yang; Li, Zhongpeng; Hsu, Chuan-Chih; Liu, Xue; Fu, Liwen; Hou, Yueh-Ju; Du, Yanyan; Xie, Shaojun; Zhang, Chunguang; Gao, Jinghui; Cao, Minjie; Huang, Xiaosan; Zhu, Yingfang; Tang, Kai; Wang, Xingang; Tao, W Andy; Xiong, Yan; Zhu, Jian-Kang

    2018-01-04

    As sessile organisms, plants must adapt to variations in the environment. Environmental stress triggers various responses, including growth inhibition, mediated by the plant hormone abscisic acid (ABA). The mechanisms that integrate stress responses with growth are poorly understood. Here, we discovered that the Target of Rapamycin (TOR) kinase phosphorylates PYL ABA receptors at a conserved serine residue to prevent activation of the stress response in unstressed plants. This phosphorylation disrupts PYL association with ABA and with PP2C phosphatase effectors, leading to inactivation of SnRK2 kinases. Under stress, ABA-activated SnRK2s phosphorylate Raptor, a component of the TOR complex, triggering TOR complex dissociation and inhibition. Thus, TOR signaling represses ABA signaling and stress responses in unstressed conditions, whereas ABA signaling represses TOR signaling and growth during times of stress. Plants utilize this conserved phospho-regulatory feedback mechanism to optimize the balance of growth and stress responses. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. Insulin-like Growth Factor I as a Skeletal Maturity Indicator

    Directory of Open Access Journals (Sweden)

    B K Sharmada

    2014-01-01

    Conclusion: Blood spot IGF-I correlates well with skeletal age as determined by radiographic techniques. IGF-I can act as a potential skeletal maturity indicator without the hazard of additional radiographic exposure.

  19. Serum insulin-like growth factor-I in 1030 healthy children, adolescents, and adults

    DEFF Research Database (Denmark)

    Juul, A; Bang, P; Hertel, Niels

    1994-01-01

    IGF-I concentrations increased slowly in prepubertal children from 80-200 micrograms/L with a further steep increase during puberty to approximately 500 micrograms/L. After puberty, a subsequent continuous fall in circulating IGF-I levels was apparent throughout adulthood to a mean of 100 micrograms....../L at the age of 80 yr (P puberty was diminished when data were separated according to sex...... and Tanner stage of puberty. Interestingly, we found a significant variation with age within the Tanner stages; there was an increase in serum IGF-I concentrations with age in the early pubertal stages and a decrease in the late stages (P

  20. Serum insulin-like growth factor-I in 1030 healthy children, adolescents, and adults

    DEFF Research Database (Denmark)

    Juul, A; Bang, P; Hertel, Niels

    1994-01-01

    IGF-I concentrations increased slowly in prepubertal children from 80-200 micrograms/L with a further steep increase during puberty to approximately 500 micrograms/L. After puberty, a subsequent continuous fall in circulating IGF-I levels was apparent throughout adulthood to a mean of 100 micrograms...... and Tanner stage of puberty. Interestingly, we found a significant variation with age within the Tanner stages; there was an increase in serum IGF-I concentrations with age in the early pubertal stages and a decrease in the late stages (P

  1. Circulating Insulin-Like Growth Factor I Regulates Its Receptor in the Brain of Male Mice.

    Science.gov (United States)

    Trueba-Saiz, A; Fernandez, A M; Nishijima, T; Mecha, M; Santi, A; Munive, V; Aleman, I Torres

    2017-02-01

    The role of IGF-1 and its receptor (IGF-1R) in brain pathology is still unclear. Thus, either reduction of IGF-IR or treatment with IGF-1, two apparently opposite actions, has proven beneficial in brain diseases such as Alzheimer's dementia. A possible explanation of this discrepancy is that IGF-1 down-regulates brain IGF-1R levels, as previously seen in a mouse Alzheimer's dementia model. We now explored whether under normal conditions IGF-1 modulates its receptor. We first observed that in vitro, IGF-1 reduced IGF-1R mRNA levels in all types of brain cells including neurons, astrocytes, microglia, endothelial cells, and oligodendrocytes. IGF-1 also inhibited its own expression in neurons and brain endothelium. Next, we analyzed the in vivo actions of IGF-1. Because serum IGF-1 can enter the brain, we injected mice with IGF-1 ip. As soon as 1 hour after the injection, decreased hippocampal IGF-1 levels were observed, followed by increased IGF-1 and IGF-1R mRNAs 6 hours later. Because environmental enrichment (EE) stimulates the entrance of serum IGF-1 into the brain, we analyzed whether a physiological entrance of IGF-1 also produced changes in brain IGF-1R. Stimulation of IGF-1R by EE triggered a gradual decrease in hippocampal IGF-1 levels. After 6 hours of EE exposure, IGF-1 levels reached a significant decrease in parallel with increased IGF-1R expression. After longer times, IGF-1R mRNA levels returned to baseline. Thus, under nonpathological conditions, IGF-1 regulates brain IGF-1R. Because baseline IGF-1R levels are rapidly restored, a tight control of brain IGF-1R expression seems to operate under physiological conditions. Copyright © 2017 by the Endocrine Society.

  2. Diminished concentrations of insulin-like growth factor I in cystic fibrosis

    DEFF Research Database (Denmark)

    Laursen, Erik; Juul, A; Lanng, S

    1995-01-01

    on IGF-I in cystic fibrosis are sparse and conflicting. From 1990-3, 235 of our 240 patients (114 males, 121 females, median age 16.2 years, ranged 0.1-44.0 years) had IGF-I measured once by radioimmunoassay. IGF-I was significantly reduced compared with a healthy Scandinavian control population: mean...

  3. Insulin-Like Growth Factor-I as intraovarian regulator of hyaluronic acid synthesis

    Czech Academy of Sciences Publication Activity Database

    Nagyová, Eva; Procházka, Radek

    č. 28 (2002), s. 31 ISSN 1476-3990. [Society for Reproduction and Fertility-Annual Conference. 00.06.2002-00.06.2002, Leeds] R&D Projects: GA AV ČR IAA5045102 Keywords : insulin Subject RIV: EB - Genetics ; Molecular Biology

  4. Evaluation of insulin-like growth factor-I gene polymorphism in ...

    African Journals Online (AJOL)

    This study aimed to detect the genetic polymorphism of IGF-1 in different Egyptian sheep and goat breeds. The amplified fragments at 320-bp were digested with HaeIII endonuclease and the results show the presence of three different genotypes: CC (15.71%), CG (29.29%) and GG (55.0%). The nucleotide sequence ...

  5. Serum insulin-like growth factor-I adult reference values for an ...

    African Journals Online (AJOL)

    Considering the importance of IGF-I local normal range, the aim of this study was to determine reference values for IGF-I (Immulite 2000) in a Brazilian adult population from the city of Rio de Janeiro. This study included samples of blood taken from 484 healthy subjects (251 men, 233 women) aged 18 to 70. The subjects ...

  6. Plasma dehydroepiandrosterone sulphate and insulin-like growth factor I levels in obstructive sleep apnoea syndrome.

    Science.gov (United States)

    Makino, Shinya; Fujiwara, Masayoshi; Handa, Hiroshi; Fujie, Tatsuro; Aoki, Yoshiyuki; Hashimoto, Kozo; Terada, Yoshio; Sugimoto, Tamotsu

    2012-04-01

    We aimed to assess whether obstructive sleep apnoea syndrome (OSAS) affects plasma IGF-1 and dehydroepiandrosterone sulphate (DHEA-S) levels in men, factors implicated in the development of age-related metabolic disorders. We conducted a cross-sectional and longitudinal clinical study. We measured plasma IGF-1 and DHEA-S levels in 191 non-drug-treated Japanese men (34 primary snorers (PS), 88 patients with mild-to-moderate OSAS and 69 patients severe OSAS ). Plasma IGF-1 and DHEA-S were negatively correlated with age. Plasma IGF-1 was also negatively correlated with plasma glucose, HOMA-IR and systolic blood pressure and apnoea parameters such as the apnoea-hypopnea index, minimum oxygen saturation and slow-wave sleep (SWS) time. Plasma DHEA-S was associated with plasma glucose, HbA1c and free fatty acid and was negatively correlated with SWS time. To eliminate the influence of age, PS, patients with mild-to-moderate OSAS and severe OSAS were divided into three groups by age: young (plasma IGF-1 or DHEA-S levels, respectively, than did the corresponding snorers and mild-to-moderate OSAS groups. Continuous positive airway pressure therapy for generally 16-18 months increased plasma IGF-1 levels in patients with severe OSAS aged Plasma DHEA-S levels were increased in patients with severe OSAS aged plasma IGF-1 and DHEA-S levels in younger, but not elderly Japanese men, which is potentially associated with the development of metabolic abnormalities. © 2012 Blackwell Publishing Ltd.

  7. Serum insulin-like growth factor-I adult reference values for an ...

    African Journals Online (AJOL)

    use

    2011-12-07

    Dec 7, 2011 ... 2Laboratório de Morfometria, Metabolismo e Doença Cardiovascular, Instituto de Biologia Roberto Alcantara Gomes,. Universidade do Estado do Rio de Janeiro, Rio de Janeiro, Brazil. 3Departamento de Tecnologias da Informação e Educação em Saúde, Faculdade de Ciências Médicas,. Universidade ...

  8. Effect of modeled microgravity on radiation-induced adaptive response of root growth in Arabidopsis thaliana

    International Nuclear Information System (INIS)

    Deng, Chenguang; Wang, Ting; Wu, Jingjing; Xu, Wei; Li, Huasheng; Liu, Min

    2017-01-01

    Highlights: • The radio-adaptive response (RAR) of A. thaliana root growth is modulated in microgravity. • The DNA damage repairs in RAR are regulated by microgravity. • The phytohormone auxin plays a regulatory role in the modulation of microgravity on RAR of root growth. - Abstract: Space particles have an inevitable impact on organisms during space missions; radio-adaptive response (RAR) is a critical radiation effect due to both low-dose background and sudden high-dose radiation exposure during solar storms. Although it is relevant to consider RAR within the context of microgravity, another major space environmental factor, there is no existing evidence as to its effects on RAR. In the present study, we established an experimental method for detecting the effects of gamma-irradiation on the primary root growth of Arabidopsis thaliana, in which RAR of root growth was significantly induced by several dose combinations. Microgravity was simulated using a two-dimensional rotation clinostat. It was shown that RAR of root growth was significantly inhibited under the modeled microgravity condition, and was absent in pgm-1 plants that had impaired gravity sensing in root tips. These results suggest that RAR could be modulated in microgravity. Time course analysis showed that microgravity affected either the development of radio-resistance induced by priming irradiation, or the responses of plants to challenging irradiation. After treatment with the modeled microgravity, attenuation in priming irradiation-induced expressions of DNA repair genes (AtKu70 and AtRAD54), and reduced DNA repair efficiency in response to challenging irradiation were observed. In plant roots, the polar transportation of the phytohormone auxin is regulated by gravity, and treatment with an exogenous auxin (indole-3-acetic acid) prevented the induction of RAR of root growth, suggesting that auxin might play a regulatory role in the interaction between microgravity and RAR of root growth.

  9. Altered growth response to exogenous auxin and gibberellic acid by gravistimulation in pulvini of Avena sativa

    Science.gov (United States)

    Brock, T. G.; Kaufman, P. B.

    1988-01-01

    Pulvini of excised segments from oats (Avena sativa L. cv Victory) were treated unilaterally with indoleacetic acid (IAA) or gibberellic acid (GA3) with or without gravistimulation to assess the effect of gravistimulation on hormone action. Optimum pulvinus elongation growth (millimeters) and segment curvature (degrees) over 24 hours were produced by 100 micromolar IAA in vertical segments. The curvature response to IAA at levels greater than 100 micromolar, applied to the lower sides of gravistimulated (90 degrees) pulvini, was significantly less than the response to identical levels in vertical segments. Furthermore, the bending response of pulvini to 100 micromolar IAA did not vary significantly over a range of presentation angles between 0 and 90 degrees. In contrast, the response to IAA at levels less than 10 micromolar, with gravistimulation, was approximately the sum of the responses to gravistimulation alone and to IAA without gravistimulation. This was observed over a range of presentation angles. Also, GA3 (0.3-30 micromolar) applied to the lower sides of horizontal segments significantly enhanced pulvinus growth and segment curvature, although exogenous GA3 over a range of concentrations had no effect on pulvinus elongation growth or segment curvature in vertical segments. The response to GA3 (10 micromolar) plus IAA (1.0 or 100 micromolar) was additive for either vertical or horizontal segments. These results indicate that gravistimulation produces changes in pulvinus responsiveness to both IAA and GA3 and that the changes are unique for each growth regulator. It is suggested that the changes in responsiveness may result from processes at the cellular level other than changes in hormonal sensitivity.

  10. Growth temperature exerts differential physiological and transcriptional responses in laboratory and wine strains of Saccharomyces cerevisiae.

    Science.gov (United States)

    Pizarro, Francisco J; Jewett, Michael C; Nielsen, Jens; Agosin, Eduardo

    2008-10-01

    Laboratory strains of Saccharomyces cerevisiae have been widely used as a model for studying eukaryotic cells and mapping the molecular mechanisms of many different human diseases. Industrial wine yeasts, on the other hand, have been selected on the basis of their adaptation to stringent environmental conditions and the organoleptic properties that they confer to wine. Here, we used a two-factor design to study the responses of a standard laboratory strain, CEN.PK113-7D, and an industrial wine yeast strain, EC1118, to growth temperatures of 15 degrees C and 30 degrees C in nitrogen-limited, anaerobic, steady-state chemostat cultures. Physiological characterization revealed that the growth temperature strongly impacted the biomass yield of both strains. Moreover, we found that the wine yeast was better adapted to mobilizing resources for biomass production and that the laboratory yeast exhibited higher fermentation rates. To elucidate mechanistic differences controlling the growth temperature response and underlying adaptive mechanisms between the strains, DNA microarrays and targeted metabolome analysis were used. We identified 1,007 temperature-dependent genes and 473 strain-dependent genes. The transcriptional response was used to identify highly correlated gene expression subnetworks within yeast metabolism. We showed that temperature differences most strongly affect nitrogen metabolism and the heat shock response. A lack of stress response element-mediated gene induction, coupled with reduced trehalose levels, indicated that there was a decreased general stress response at 15 degrees C compared to that at 30 degrees C. Differential responses among strains were centered on sugar uptake, nitrogen metabolism, and expression of genes related to organoleptic properties. Our study provides global insight into how growth temperature affects differential physiological and transcriptional responses in laboratory and wine strains of S. cerevisiae.

  11. Growth on ATP Elicits a P-Stress Response in the Picoeukaryote Micromonas pusilla.

    Directory of Open Access Journals (Sweden)

    LeAnn P Whitney

    Full Text Available The surface waters of oligotrophic oceans have chronically low phosphate (Pi concentrations, which renders dissolved organic phosphorus (DOP an important nutrient source. In the subtropical North Atlantic, cyanobacteria are often numerically dominant, but picoeukaryotes can dominate autotrophic biomass and productivity making them important contributors to the ocean carbon cycle. Despite their importance, little is known regarding the metabolic response of picoeukaryotes to changes in phosphorus (P source and availability. To understand the molecular mechanisms that regulate P utilization in oligotrophic environments, we evaluated transcriptomes of the picoeukaryote Micromonas pusilla grown under Pi-replete and -deficient conditions, with an additional investigation of growth on DOP in replete conditions. Genes that function in sulfolipid substitution and Pi uptake increased in expression with Pi-deficiency, suggesting cells were reallocating cellular P and increasing P acquisition capabilities. Pi-deficient M. pusilla cells also increased alkaline phosphatase activity and reduced their cellular P content. Cells grown with DOP were able to maintain relatively high growth rates, however the transcriptomic response was more similar to the Pi-deficient response than that seen in cells grown under Pi-replete conditions. The results demonstrate that not all P sources are the same for growth; while M. pusilla, a model picoeukaryote, may grow well on DOP, the metabolic demand is greater than growth on Pi. These findings provide insight into the cellular strategies which may be used to support growth in a stratified future ocean predicted to favor picoeukaryotes.

  12. Response to three years of growth hormone therapy in girls with Turner syndrome

    Directory of Open Access Journals (Sweden)

    Hong Kyu Park

    2013-03-01

    Full Text Available PurposeShort stature is the most common finding in patients with Turner syndrome. Improving the final adult height in these patients is a challenge both for the patients and physicians. We investigated the clinical response of patients to growth hormone treatment for height improvement over the period of three years.MethodsReview of medical records from 27 patients with Turner syndrome treated with recombinant human growth hormone for more than 3 years was done. Differences in the changes of height standard deviation scores according to karyotype were measured and factors influencing the height changes were analyzed.ResultsThe response to recombinant human growth hormone was an increase in the height of the subjects to a mean value of 1.1 standard deviation for subjects with Turner syndrome at the end of the 3-year treatment. The height increment in the first year was highest. The height standard deviation score in the third year was negatively correlated with the age at the beginning of the recombinant human growth hormone treatment. Different karyotypes in subjects did not seem to affect the height changes.ConclusionEarly growth hormone administration in subjects with Turner syndrome is helpful to improve height response to the treatment.

  13. Placental restriction of fetal growth reduces cutaneous responses to antigen after sensitization in sheep.

    Science.gov (United States)

    Wooldridge, Amy L; Bischof, Robert J; Meeusen, Els N; Liu, Hong; Heinemann, Gary K; Hunter, Damien S; Giles, Lynne C; Kind, Karen L; Owens, Julie A; Clifton, Vicki L; Gatford, Kathryn L

    2014-04-01

    Prenatal and early childhood exposures are implicated as causes of allergy, but the effects of intrauterine growth restriction on immune function and allergy are poorly defined. We therefore evaluated effects of experimental restriction of fetal growth on immune function and allergic sensitization in adolescent sheep. Immune function (circulating total red and white blood cells, neutrophils, lymphocytes, monocytes, eosinophils, and basophils, and the antibody response to Clostridial vaccination) and responses to house dust mite (HDM) allergen and ovalbumin (OVA) antigen sensitization (specific total Ig, IgG1, and IgE antibodies, and cutaneous hypersensitivity) were investigated in adolescent sheep from placentally restricted (PR, n = 23) and control (n = 40) pregnancies. Increases in circulating HDM-specific IgE (P = 0.007) and OVA-specific IgE (P = 0.038) were greater in PR than control progeny. PR did not alter total Ig, IgG1, or IgM responses to either antigen. PR increased OVA-specific but not HDM-specific IgA responses in females only (P = 0.023). Multiple birth increased Ig responses to OVA in a sex-specific manner. PR decreased the proportion of positive cutaneous hypersensitivity responders to OVA at 24 h (P = 0.030) but had no effect on cutaneous responses to HDM. Acute wheal responses to intradermal histamine correlated positively with birth weight in singletons (P = 0.023). Intrauterine growth restriction may suppress inflammatory responses in skin downstream of IgE induction, without impairment in antibody responses to a nonpolysaccharide vaccine. Discord between cutaneous and IgE responses following sensitization suggests new mechanisms for prenatal allergy programming.

  14. Relationship between hyperthermic killing and the mitogenic response to serum and growth factors

    International Nuclear Information System (INIS)

    Lin, P.P.; Hahn, G.M.

    1987-01-01

    The possibility that hyperthermic killing involves disruption of the mitogenic response to serum and growth factors was investigated. Subconfluent HA-1 (Chinese Hamster Ovary) cells were made quiescent by 24 hour incubation in serum-free media. Quiescent cells were stimulated with either serum or the growth factors FGF, insulin, and transferrin. DNA synthesis was measured by /sup 3/H-thymidine incorporation. Twenty-four hour incubation in serum-free media did not sensitize HA-1 cells to heat. Survival after 45 0 C heating was similar to survival of exponentially growing cells. The mitogenic response to serum and growth factors was assayed after 45 0 C heating. This correlated well with survival. Preliminary experiments using flow cytometry indicated that clonogenically live cells could be stimulated to progress from G/sub 1/ to G/sub 2/ whereas clonogenically dead (but metabolically alive) cells could not be stimulated

  15. Growth and physiological responses to varied environments among populations of Pinus ponderosa

    Science.gov (United States)

    Jianwei Zhang; Bert M. Cregg

    2005-01-01

    We investigated population responses in physiology, morphology, and growth of mature Pinus ponderosa trees to an environmental gradient across Nebraska, USA. Ten populations from western Nebraska and eastern Wyoming were grown in three 26-year-old provenance tests from the warmest and wettest site in the east (Plattsmouth) to the intermediate site in...

  16. Growth and physiological response of tall oat grass to salinity stress ...

    African Journals Online (AJOL)

    In order to evaluate the responses of tall oat grass plants to increasing salinity, we measured plant growth, ion contents, photosynthetic gas exchange, lipid peroxidation, and proline accumulation in four salt concentrations. Two tall oatgrass genotypes, ZXY03P-367 and ZXY03P-443, were grown for 14 days in greenhouse ...

  17. GROWTH RESPONSE OF SYMBODINIUM SPP. TO COMBINED TEMPERATURE AND UV RADIATION

    Science.gov (United States)

    Rogers, J.E. and D. Marcovich. In press. Growth Response of a Coral Symbiont, Symbiodinium sp., to Combined Temperature and UV Radiation Exposure (Abstract). To be presented at the ASLO 2004 Summer Meeting: The Changing Landscapes of Oceans and Freshwater, 13-18 June 2004, Savann...

  18. Plant Growth in Controlled Environments in Response to Characteristics of Nutrient Solutions

    Science.gov (United States)

    Raper, C. D., Jr.

    1982-01-01

    Emphasis was given to environmental factors that alter the flux of carbohydrate from the shoot to the root system to support the absorption of nitrogen and the subsequent interaction between nitrogen uptake and whole plant growth. Only the nitrate form of nitrogen was utilized in order to establish base line responses for evaluation of future studies utilizing both ammonium and nitrate.

  19. Growth and grazing responses of two chloroplast-retaining dinoflagellates: effect of irradiance and prey species

    DEFF Research Database (Denmark)

    Jakobsen, Hans Henrik; Hansen, P.J.; Larsen, J.

    2000-01-01

    The effect of irradiance on growth and grazing responses of 2 phagotrophic dinoflagellates, Gymnodinium gracilentum Campbell 1973 and Amphidinium poecilochroum Larsen 1985, was studied. While G. gracilentum belongs to the plankton, A. poecilochroum is a benthic species that primarily feeds on prey...

  20. Growth and nutrition response of young sweetgum plantations to repeated nitrogen fertilization on two site types

    Science.gov (United States)

    D. Andrew Scott; James A. Burger; Donald J. Kaczmarek; Michael B. Kane

    2004-01-01

    Short-rotation intensive tree culture is being investigated in the southern United States as a method of producing hardwood fiber, but little is known about the early productivity and nutritional needs of these systems, especially on different site types. We studied the growth and foliar nutrition response of two sweetgum (Liquidambar styraciflua L...

  1. Physiological and Growth Responses of Midrotation Loblolly Pine to Treatments of Fire, Herbicide, and Fertilizer

    Science.gov (United States)

    Emily J. Goodwin; Lisa M. Marino McInnis; Hans M. Williams; Brian P. Oswald; Kenneth W. Farrish

    2004-01-01

    The objectives of this study were to examine the effects of fertilizer and understory vegetation control (herbicide and prescribed fire) on mature tree physiology and to link observed physiological responses with tree growth. Photosynthetic rate (photosynthesis), transpiration, stomatal conductance, stem diameter, and crown area were measured in two midrotation...

  2. Growth and physiological response of tall oat grass to salinity stress

    African Journals Online (AJOL)

    Jane

    2011-07-20

    Jul 20, 2011 ... In order to evaluate the responses of tall oat grass plants to increasing salinity, we measured plant growth, ion contents, photosynthetic ... population, the need to develop salt-tolerant crops is increasing. Thus, we need to ... (Rengel, 1992) and this can cause nutrient deficiencies. Growing plant in increasing ...

  3. Growth pattern responses to photoperiod across latitudes in a northern damselfly.

    Science.gov (United States)

    Sniegula, Szymon; Nilsson-Örtman, Viktor; Johansson, Frank

    2012-01-01

    Latitudinal clines in temperature and seasonality impose strong seasonal constraints on ectotherms. Studies of population differentiation in phenotypic plasticity of life history traits along latitudinal gradients are important for understanding how organisms have adapted to seasonal environments and predict how they respond to climate changes. Such studies have been scarce for species with a northern distribution. Larvae of the northern damselfly Coenagrion johanssoni originating from semivoltine central, partivoltine northern, and partivoltine northernmost Swedish populations were reared in the laboratory. To investigate whether larvae use photoperiodic cues to induce compensatory growth along this latitudinal gradient, larvae were reared under two different photoperiods corresponding to a northern and southern latitude. In addition, field adult size was assessed to test the strength of possible compensatory growth mechanisms under natural conditions and hatchling size was measured to test for maternal effects. We hypothesized that populations originating from lower latitudes would be more time constrained than high-latitude populations because they have a shorter life cycle. The results showed that low-latitude populations had higher growth rates in summer/fall. In general northern photoperiods induced higher growth rates, but this plastic response to photoperiod was strongest in the southernmost populations and negligible in the northernmost population. During spring, central populations grew faster under the southern rather than the northern photoperiod. On the other hand, northern and northernmost populations did not differ between each other and grew faster in the northern rather than in the southern photoperiod. Field sampled adults did not differ in size across the studied regions. We found a significant differentiation in growth rate across latitudes and latitudinal difference in growth rate response to photoperiod. Importantly, growth responses measured

  4. Tree Growth Response to Drought Along a Depth to Groundwater Gradient in Northern Wisconsin

    Science.gov (United States)

    Ciruzzi, D. M.; Loheide, S. P., II

    2017-12-01

    Understanding complex spatial and temporal patterns of drought-induced forest stress requires knowledge of the physiological drivers and ecosystem attributes that lead to or inhibit tree mortality. Prevailing meteorological conditions leading to drought may have lesser effect on vegetation that has evolved to avoid drought by accessing deeper soil moisture reserves or shallow groundwater to meet evapotranspiration demand. This is especially true in arid and semi-arid regions, yet groundwater use by trees is rarely explored in temperate systems and the extent to which groundwater use reduces drought vulnerability in these climates and regions is unknown. We explored responses of radial growth in temperate tress to wet and dry years across a depth to groundwater gradient from 1 to 9 meters in sandy forests in northern Wisconsin. The spatial patterns of tree growth in this watershed show areas where tree growth is influenced by depth to groundwater. Preliminary results showed trees in areas of shallower groundwater with low variability in tree growth and indicated that tree growth remains consistent during both wet and dry years. Conversely, trees in areas of deeper groundwater showed higher variability in tree growth during wet and dry years. We hypothesize that even in this humid region, the sandy soils do not retain sufficient moisture leading to potentially frequent water stress in trees and reductions in productivity. However, where and when accessible, we suspect trees use shallow groundwater to sustain evapotranspiration and maintain consistent growth during dry periods.

  5. Response to long-term growth hormone therapy in patients affected by RASopathies and growth hormone deficiency: Patterns of growth, puberty and final height data.

    Science.gov (United States)

    Tamburrino, Federica; Gibertoni, Dino; Rossi, Cesare; Scarano, Emanuela; Perri, Annamaria; Montanari, Francesca; Fantini, Maria Pia; Pession, Andrea; Tartaglia, Marco; Mazzanti, Laura

    2015-11-01

    RASopathies are developmental disorders caused by heterozygous germline mutations in genes encoding proteins in the RAS-MAPK signaling pathway. Reduced growth is a common feature. Several studies generated data on growth, final height (FH), and height velocity (HV) after growth hormone (GH) treatment in patients with these disorders, particularly in Noonan syndrome, the most common RASopathy. These studies, however, refer to heterogeneous cohorts in terms of molecular information, GH status, age at start and length of therapy, and GH dosage. This work reports growth data in 88 patients affected by RASopathies with molecularly confirmed diagnosis, together with statistics on body proportions, pubertal pattern, and FH in 33, including 16 treated with GH therapy for proven GH deficiency. Thirty-three patients showed GH deficiency after pharmacological tests, and were GH-treated for an average period of 6.8 ± 4.8 years. Before starting therapy, HV was -2.6 ± 1.3 SDS, and mean basal IGF1 levels were -2.0 ± 1.1 SDS. Long-term GH therapy, starting early during childhood, resulted in a positive height response compared with untreated patients (1.3 SDS in terms of height-gain), normalizing FH for Ranke standards but not for general population and Target Height. Pubertal timing negatively affected pubertal growth spurt and FH, with IGF1 standardized score increased from -2.43 to -0.27 SDS. During GH treatment, no significant change in bone age velocity, body proportions, or cardiovascular function was observed. © 2015 Wiley Periodicals, Inc.

  6. Climate Response of Tree Radial Growth at Different Timescales in the Qinling Mountains.

    Directory of Open Access Journals (Sweden)

    Changfeng Sun

    Full Text Available The analysis of the tree radial growth response to climate is crucial for dendroclimatological research. However, the response relationships between tree-ring indices and climatic factors at different timescales are not yet clear. In this study, the tree-ring width of Huashan pine (Pinus armandii from Huashan in the Qinling Mountains, north-central China, was used to explore the response differences of tree growth to climatic factors at daily, pentad (5 days, dekad (10 days and monthly timescales. Correlation function and linear regression analysis were applied in this paper. The tree-ring width showed a more sensitive response to daily and pentad climatic factors. With the timescale decreasing, the absolute value of the maximum correlation coefficient between the tree-ring data and precipitation increases as well as temperature (mean, minimum and maximum temperature. Compared to the other three timescales, pentad was more suitable for analysing the response of tree growth to climate. Relative to the monthly climate data, the association between the tree-ring data and the pentad climate data was more remarkable and accurate, and the reconstruction function based on the pentad climate was also more reliable and stable. We found that the major climatic factor limiting Huashan pine growth was the precipitation of pentads 20-35 (from April 6 to June 24 rather than the well-known April-June precipitation. The pentad was also proved to be a better timescale for analysing the climate and tree growth in the western and eastern Qinling Mountains. The formation of the earlywood density of Chinese pine (Pinus tabulaeformis from Shimenshan in western Qinling was mainly affected by the maximum temperature of pentads 28-32 (from May 16 to June 9. The maximum temperature of pentads 28-33 (from May 16 to June 14 was the major factor affecting the ring width of Chinese pine from Shirenshan in eastern Qinling.

  7. Model of avascular tumor growth and response to low dose exposure

    Science.gov (United States)

    Rodriguez Aguirre, J. M.; Custidiano, E. R.

    2011-12-01

    A single level cellular automata model is described and used to simulate early tumor growth, and the response of the tumor cells under low dose radiation affects. In this model the cell cycle of the population of normal and cancer cells is followed. The invasion mechanism of the tumor is simulated by a local factor that takes into account the microenvironment hardness to cell development, in a picture similar to the AMTIH model. The response of normal and cancer cells to direct effects of radiation is tested for various models and a model of bystander response is implemented.

  8. Model of avascular tumor growth and response to low dose exposure

    International Nuclear Information System (INIS)

    Rodriguez Aguirre, J M; Custidiano, E R

    2011-01-01

    A single level cellular automata model is described and used to simulate early tumor growth, and the response of the tumor cells under low dose radiation affects. In this model the cell cycle of the population of normal and cancer cells is followed. The invasion mechanism of the tumor is simulated by a local factor that takes into account the microenvironment hardness to cell development, in a picture similar to the AMTIH model. The response of normal and cancer cells to direct effects of radiation is tested for various models and a model of bystander response is implemented.

  9. Growth promotion of Lactuca sativa in response to volatile organic compounds emitted from diverse bacterial species.

    Science.gov (United States)

    Fincheira, Paola; Venthur, Herbert; Mutis, Ana; Parada, Maribel; Quiroz, Andrés

    2016-12-01

    Agrochemicals are currently used in horticulture to increase crop production. Nevertheless, their indiscriminate use is a relevant issue for environmental and legal aspects. Alternative tools for reducing fertilizers and synthetic phytohormones are being investigated, such as the use of volatile organic compounds (VOCs) as growth inducers. Some soil bacteria, such as Pseudomonas and Bacillus, stimulate Arabidopsis and tobacco growth by releasing VOCs, but their effects on vegetables have not been investigated. Lactuca sativa was used as model vegetable to investigate bacterial VOCs as growth inducers. We selected 10 bacteria strains, belonging to Bacillus, Staphylococcus and Serratia genera that are able to produce 3-hydroxy-2-butanone (acetoin), a compound with proven growth promoting activity. Two-day old-seedlings of L. sativa were exposed to VOCs emitted by the selected bacteria grown in different media cultures for 7 days. The results showed that the VOCs released from the bacteria elicited an increase in the number of lateral roots, dry weight, root growth and shoot length, depending on the media used. Three Bacillus strains, BCT53, BCT9 and BCT4, were selected according to its their growth inducing capacity. The BCT9 strain elicited the greatest increases in dry weight and primary root length when L. sativa seedlings were subjected to a 10-day experiment. Finally, because acetoin only stimulated root growth, we suggest that other volatiles could be responsible for the growth promotion of L. sativa. In conclusion, our results strongly suggest that bacteria volatiles can be used as growth-inducers as alternative or complementary strategies for application in horticulture species. Copyright © 2016 Elsevier GmbH. All rights reserved.

  10. Growth, photosynthesis, and antioxidant responses of Vigna unguiculata L. treated with hydrogen peroxide

    Directory of Open Access Journals (Sweden)

    Syed Aiman Hasan

    2016-12-01

    Full Text Available Cowpea (Vigna unguiculata L. is an important legume well grown in semiarid and arid environment. Hydrogen peroxide solutions (0.1, 0.5, 1.0, and 1.5 mM have been used to optimize growth and photosynthetic performance of cowpea plant at two growth stages [30 and 45 DAS (days of sowing]. Foliar application of H2O2 at 0.5 > 1.0 mM solution at 29 DAS optimally promoted the photosynthetic attributes [leaf chlorophyll content, net photosynthetic rate (PN, water use efficiency, and maximum quantum yield of PSII (Fv/Fm] and growth performance [root and shoot length; fresh and dry weight] of plants where the responses were more significant at the later growth stage. It was favored by activity of enzymes as carbonic anhydrase [CA; E.C. 4.2.1.1] and nitrate reductase [NR, E.C. 1.6.6.1] and those of antioxidant enzymes viz. peroxidase [POX; EC 1.11.1.7], catalase [CAT; EC 1.11.1.6], and superoxide dismutase [SOD; EC 1.15.1.1] and leaf proline content. Strengthened root system and antioxidant activity, particularly leaf proline level appeared to be the key factor for efficient photosynthesis and growth responses.

  11. Growth Response of Two Phaseolus mungo L. Cultivars Induced by Arbuscular Mycorrhizal Fungi and Trichoderma viride

    Directory of Open Access Journals (Sweden)

    Navnita Sharma

    2016-01-01

    Full Text Available The present investigation aimed to quantify the difference in response of two Phaseolus mungo L. cultivars (i.e., UH-1 and IPU-94-1 to Glomus mosseae (G, that is, Funneliformis mosseae, Acaulospora laevis (A, and Trichoderma viride (T, in different combinations or alone. All the treatments were inoculated with Bradyrhizobium japonicum to ensure nodulation as soil used in the experiment was sterilized. After 120 days of inoculation, plants were analyzed for chlorophyll content, nodulation, mycorrhization, leaf area, and protein content. Results indicate variation in growth response of two cultivars with different treatments. Triple inoculation of plants with G + A + T proved to be the best treatment for growth followed by G + T in both cultivars. Our work allowed the selection of P. mungo L. cultivar UH-1 as highly mycorrhizal responsive as compared to IPU-94-1 and G. mosseae to be an efficient bioinoculant as compared to A. laevis for growth enhancement of P. mungo. Further characterization of P. mungo genotypes will enhance our knowledge of physiological and genetic mechanism behind increase in plant growth and yield due to AM symbiosis.

  12. Target of Rapamycin (TOR) Regulates Growth in Response to Nutritional Signals.

    Science.gov (United States)

    Weisman, Ronit

    2016-10-01

    All organisms can respond to the availability of nutrients by regulating their metabolism, growth, and cell division. Central to the regulation of growth in response to nutrient availability is the target of rapamycin (TOR) signaling that is composed of two structurally distinct complexes: TOR complex 1 (TORC1) and TOR complex 2 (TORC2). The TOR genes were first identified in yeast as target of rapamycin, a natural product of a soil bacterium, which proved beneficial as an immunosuppressive and anticancer drug and is currently being tested for a handful of other pathological conditions including diabetes, neurodegeneration, and age-related diseases. Studies of the TOR pathway unraveled a complex growth-regulating network. TOR regulates nutrient uptake, transcription, protein synthesis and degradation, as well as metabolic pathways, in a coordinated manner that ensures that cells grow or cease growth in response to nutrient availability. The identification of specific signals and mechanisms that stimulate TOR signaling is an active and exciting field of research that has already identified nitrogen and amino acids as key regulators of TORC1 activity. The signals, as well as the cellular functions of TORC2, are far less well understood. Additional open questions in the field concern the relationships between TORC1 and TORC2, as well as the links with other nutrient-responsive pathways. Here I review the main features of TORC1 and TORC2, with a particular focus on yeasts as model organisms.

  13. Is there an association between root architecture and mycorrhizal growth response?

    Science.gov (United States)

    Maherali, Hafiz

    2014-10-01

    The symbiosis between arbuscular mycorrhizal (AM) fungi and plants is evolutionarily widespread. The response of plant growth to inoculation by these fungi (mycorrhizal growth response; MGR) is highly variable, ranging from positive to negative. Some of this variation is hypothesized to be associated with root structure and function. Specifically, species with a coarse root architecture, and thus a limited intrinsic capacity to absorb soil nutrients, are expected to derive the greatest growth benefit from inoculation with AM fungi. To test this hypothesis, previously published literature and phylogenetic information were combined in a meta-analysis to examine the magnitude and direction of relationships among several root architectural traits and MGR. Published studies differed in the magnitude and direction of relationships between root architecture and MGR. However, when combined, the overall relationship between MGR and allocation to roots, root diameter, root hair length and root hair density did not differ significantly from zero. These findings indicate that possessing coarse roots is not necessarily a predictor of plant growth response to AM fungal colonization. Root architecture is therefore unlikely to limit the evolution of variation in MGR. © 2014 The Authors. New Phytologist © 2014 New Phytologist Trust.

  14. Response of alpine vegetation growth dynamics to snow cover phenology on the Tibetan Plateau

    Science.gov (United States)

    Wang, X.; Wu, C.

    2017-12-01

    Alpine vegetation plays a crucial role in global energy cycles with snow cover, an essential component of alpine land cover showing high sensitivity to climate change. The Tibetan Plateau (TP) has a typical alpine vegetation ecosystem and is rich of snow resources. With global warming, the snow of the TP has undergone significant changes that will inevitably affect the growth of alpine vegetation, but observed evidence of such interaction is limited. In particular, a comprehensive understanding of the responses of alpine vegetation growth to snow cover variability is still not well characterized on TP region. To investigate this, we calculated three indicators, the start (SOS) and length (LOS) of growing season, and the maximum of normalized difference vegetation index (NDVImax) as proxies of vegetation growth dynamics from the Moderate Resolution Imaging Spectroradiometer (MODIS) data for 2000-2015. Snow cover duration (SCD) and melt (SCM) dates were also extracted during the same time frame from the combination of MODIS and the Interactive Multi-sensor Snow and Ice Mapping System (IMS) data. We found that the snow cover phenology had a strong control on alpine vegetation growth dynamics. Furthermore, the responses of SOS, LOS and NDVImax to snow cover phenology varied among plant functional types, eco-geographical zones, and temperature and precipitation gradients. The alpine steppes showed a much stronger negative correlation between SOS and SCD, and also a more evidently positive relationship between LOS and SCD than other types, indicating a longer SCD would lead to an earlier SOS and longer LOS. Most areas showed positive correlation between SOS and SCM, while a contrary response was also found in the warm but drier areas. Both SCD and SCM showed positive correlations with NDVImax, but the relationship became weaker with the increase of precipitation. Our findings provided strong evidences between vegetation growth and snow cover phenology, and changes in

  15. Salt Stress Responses of Pigeon Pea (Cajanus Cajan) on Growth, Yield and Some Biochemical Attributes

    International Nuclear Information System (INIS)

    Tayyab, A.; Azeem, M.; Ahmad, N; Ahmad, R.; Qasim, M.

    2016-01-01

    Growth responses of leguminous plants to salinity vary considerably among species. Pigeon pea (Cajanus cajan (L.) Millsp.) is a sub-tropical crop, grown worldwide particularly in South Asia for edible and fodder purposes, while little is known about its salinity tolerance. In order to investigate the effect of salinity, plants were established at six different levels of sea salt concentrations i.e. 0.5, 1.6, 2.8, 3.5, 3.8 and 4.3 (EC/sub e/ dS.m/sup -1/). Plant growth was measured using vegetative (height, fresh and dry biomass, moisture, relative growth rate (RGR) and specific shoot length (SSL)), reproductive (number of flowers, pods, seeds and seed weight) and some biochemical parameters (chlorophylls, carotenoids, sugars and proteins). Pigeon pea showed a salt sensitive growth response, however, it survived up to 3.5 (EC/sub e/ dS.m/sup -1/) sea salt salinity. Plant height, biomass, SSL and RGR linearly decreased under saline conditions. Leaf pigments increased (chlorophylls) or maintained (carotenoids) at 1.6 dS.m/sup -1/ and subsequently decreased in higher salinity. Low moisture content and succulence along with more accumulation of soluble sugars and proteins may be attributed to leaf osmotic adjustments at low salinity. Salinity adversely affect reproductive growth of C. cajan where production of flowers, pods, number of seeds and seed weight were significantly reduced. Present study provides basic information related to plant growth, seed yield and some biochemical attributes, which suggest C. cajan as a salt sensitive leguminous crop. However, detailed information is required to understand the eco-physiological responses of this plant under field and green house conditions. (author)

  16. Growth Responses of Fish During Chronic Exposure of Metal Mixture under Laboratory Conditions

    Directory of Open Access Journals (Sweden)

    Saima Naz and Muhammad Javed

    2013-07-01

    Full Text Available Growth responses of five fish species viz. Catla catla, Labeo rohita, Cirrhina mrigala, Ctenopharyngodon idella and Hypophthalmichthys molitrix were determined, separately, under chronic exposure of binary mixture of metals (Zn+Ni at sub-lethal concentrations (1/3rd of LC50 for 12 weeks. Randomized complete block design (RCBD was followed to conduct this research work. The groups (10 fish each of Catla catla, Labeo rohita, Cirrhina mrigala, Ctenopharyngodon idella and Hypophthalmichthys molitrix having almost similar weights were investigated for their growth responses and metals bioaccumulation patterns in their body organs during chronic exposure of Zn+Ni mixture. The bioaccumulation of metals in the fish body organs viz. gills, liver, kidney, fins, bones, muscle and skin were also determined before and after growth trails under the stress of metals mixture. The exposure of fish to sub-lethal concentrations of mixture caused significant impacts on the average wet weight increments of five fish species. Ctenopharyngodon idella and Labeo rohita attained significantly higher weights, followed by that of Hypophthalmichthys molitrix, Cirrhina mrigala and Catla catla. However, the growth of metals mixture exposed fish species was significantly lesser than that of control fish (un-stressed. Significantly variable condition factor values reflected the degree of fish well-beings that correlated directly with fish growth and metal exposure concentration. Any significant change in feed intake, due to stress, is reflected in terms of fish growth showing the impacts of metal mixture on fish growth were either additive or antagonist / synergistic. Accumulation of all the metals in fish body followed the general order: liver>kidney>gills> skin >muscle> fins >bones.

  17. Growth response of Lebanon cedar (Cedrus libani) plantations to thinning intensity in Western Turkey.

    Science.gov (United States)

    Carus, Serdar; Catal, Yilmaz

    2010-09-01

    This paper presents the growth response of 25 yr old Lebanon cedar (Cedrus libani A. Rich.) plantation to thinnings of different intensities in Isparta in western Turkey. The thinning intensity was measured by using the residual basal area (%) as parameter. In spring of 2005, three treatments were tested; light, moderate and heavy thinning with respectively 10, 25 and 35% of basal area removed. The statistical design of the experiment was a randomized incomplete block with two blocks and three treatments. Variables such as diameter at breast height (diameter) and height were measured. Growth rate ratios of diameter in moderately thinned and heavily thinned stands were 1.02 and 1.03, respectively. Basal area growth rates in moderately thinned and heavily thinned plots were 0.93 and 1.05, respectively. The largest values for the mean tree were observed with the heaviest thinning treatment. Absolute diameter increment was positively correlated with initial diameter in all plots. Relative diameter growth was negatively correlated with initial diameter. Growth rate interpretations were supported by analysis of variance using Duncan's test of range multiple. The results obtained show significant differences between treatments for tree height growth, for the two inventories carried out (2005, 2008). However diameter basal area and volume were no found between treatments for tree.

  18. Geographic variation in Pacific herring growth in response to regime shifts in the North Pacific Ocean

    Science.gov (United States)

    Ito, Shin-ichi; Rose, Kenneth A.; Megrey, Bernard A.; Schweigert, Jake; Hay, Douglas; Werner, Francisco E.; Aita, Maki Noguchi

    2015-11-01

    Pacific herring populations at eight North Pacific Rim locations were simulated to compare basin-wide geographic variations in age-specific growth due to environmental influences on marine productivity and population-specific responses to regime shifts. Temperature and zooplankton abundance from a three-dimensional lower-trophic ecosystem model (NEMURO: North Pacific Ecosystem Model for Understanding Regional Oceanography) simulation from 1948 to 2002 were used as inputs to a herring bioenergetics growth model. Herring populations from California, the west coast of Vancouver Island (WCVI), Prince William Sound (PWS), Togiak Alaska, the western Bering Sea (WBS), the Sea of Okhotsk (SO), Sakhalin, and Peter the Great Bay (PGB) were examined. The half-saturation coefficients of herring feeding were calibrated to climatological conditions at each of the eight locations to reproduce averaged size-at-age data. The depth of averaging used for water temperature and zooplankton, and the maximum consumption rate parameter, were made specific to each location. Using the calibrated half-saturation coefficients, the 1948-2002 period was then simulated using daily values of water temperature and zooplankton densities interpolated from monthly model output. To detect regime shifts in simulated temperatures, zooplankton and herring growth rates, we applied sequential t-test analyses on the 54 years of hindcast simulation values. The detected shifts of herring age-5 growth showed closest match (69%) to the regime shift years (1957/58, 1970/71, 1976/77, 1988/89, 1998/99). We explored relationships among locations using cluster and principal component analyses. The first principal component of water temperature showed good correspondence to the Pacific Decadal Oscillation and all zooplankton groups showed a pan-Pacific decrease after the 1976/77 regime shift. However, the first principal component of herring growth rate showed decreased growth at the SO, PWS, WCVI and California

  19. Larval Helicoverpa zea Transcriptional, Growth and Behavioral Responses to Nicotine and Nicotiana tabacum

    Directory of Open Access Journals (Sweden)

    Linus Gog

    2014-09-01

    Full Text Available The polyphagous feeding habits of the corn earworm, Helicoverpa zea (Boddie, underscore its status as a major agricultural pest with a wide geographic distribution and host plant repertoire. To study the transcriptomic response to toxins in diet, we conducted a microarray analysis of H. zea caterpillars feeding on artificial diet, diet laced with nicotine and Nicotiana tabacum (L. plants. We supplemented our analysis with growth and aversion bioassays. The transcriptome reflects an abundant expression of proteases, chitin, cytochrome P450 and immune-related genes, many of which are shared between the two experimental treatments. However, the tobacco treatment tended to elicit stronger transcriptional responses than nicotine-laced diet. The salivary factor glucose oxidase, known to suppress nicotine induction in the plant, was upregulated by H. zea in response to tobacco but not to nicotine-laced diet. Reduced caterpillar growth rates accompanied the broad regulation of genes associated with growth, such as juvenile hormone epoxide hydrolase. The differential expression of chemosensory proteins, such as odorant binding-protein-2 precursor, as well as the neurotransmitter nicotinic-acetylcholine-receptor subunit 9, highlights candidate genes regulating aversive behavior towards nicotine. We suggest that an observed coincidental rise in cannibalistic behavior and regulation of proteases and protease inhibitors in H. zea larvae signify a compensatory response to induced plant defenses.

  20. Time dependent physiological characterization of yeast oxidative stress response and growth modulation of protein kinase/phosphatase mutants

    DEFF Research Database (Denmark)

    Altintas, Ali; Workman, Christopher

    2013-01-01

    .25, 0.50 and 1.0 mM). Understanding the growth physiology of S. cerevisiae allows us to estimate the link between genotype and stress-response phenotype. Growth physiology parameters, such as growth rate, diauxic shift times, stress-induced stasis times, were measured in fermentative batch cultures...

  1. Recognizing Non-Stationary Climate Response in Tree Growth for Southern Coastal Alaska, USA

    Science.gov (United States)

    Wiles, G. C.; Jarvis, S. K.; D'Arrigo, R.; Vargo, L. J.; Appleton, S. N.

    2012-12-01

    Stationarity in growth response of trees to climate over time is assumed in dendroclimatic studies. Recent studies of Alaskan yellow-cedar (Chamaecyparis nootkatensis (D. Don) Spach) have identified warming-induced early loss of insulating snowpack and frost damage as a mechanism that can lead to decline in tree growth, which for this species is documented over the last century. A similar stress may be put on temperature-sensitive mountain hemlock (Tsuga mertensiana (Bong.) Carrière) trees at low elevations, which in some cases show a decline in tree growth with warming temperatures. One of the challenges of using tree-ring based SAT, SST, PDO and PNA-related reconstructions for southern coastal Alaska has been understanding the response of tree-ring chronologies to the warming temperatures over the past 50 years. Comparisons of tree growth with long meteorological records from Sitka Alaska that extend back to 1830 suggest many mountain hemlock sites at low elevations are showing decreasing ring-widths, at mid elevations most sites show a steady increasing growth tracking warming, and at treeline a release is documented. The recognition of this recent divergence or decoupling of tree-ring and temperature trends allows for divergence-free temperature reconstructions using trees from moderate elevations. These reconstructions now provide a better perspective for comparing recent warming to Medieval warming and a better understanding of forest dynamics as biomes shift in response to the transition from the Little Ice Age to contemporary warming. Reconstructed temperatures are consistent with well-established, entirely independent tree-ring dated ice advances of land-terminating glaciers along the Gulf of Alaska providing an additional check for stationarity in the reconstructed interval.

  2. Determination of Wheat Yield Response Factor to Deficit Irrigation at Different Growth Stages

    Directory of Open Access Journals (Sweden)

    N. A. Ebrahimi Pak

    2012-12-01

    Full Text Available This study was conducted to determine the yield response factor (Ky of wheat with respect to deficit irrigation at different growth stages. The experiment was conducted in Shahrekord in three crop growing seasons using randomized complete blocks design with 3 replications. Treatments consisted of five levels of deficit irrigation: E0 (full irrigation, E1 (85%, E2 (70% and E3 (55% of potential evapotranspiration of wheat and E4 (no irrigation, and were assigned to six growth stages: T1 (establishment, T2 (tillering, T3 (head development, T4 (flowering, T5 (milk ripeness and T6 (maturity harvest. Potential evapotranspiration was measured using a lysimeter, which was in conditions (soil texture and structure and plant growth similar to the field. After harvesting the plants, grain yield was measured and wheat yield response factor was calculated. Results of combined analysis of variance showed that grain yield was significantly affected by deficit irrigation at establishment, tillering, head development, flowering and milk ripeness stages. The highest and the lowest grain yields (6354 and 2203 kg/ha, respectively were obtained in E0 and E4 treatments, respectively. Potential evapotranspiration of wheat was 641 mm in this area. Yield response factors (ky were 0.55-0.76 in T1 growth stage, 0.58-0.97 in T2, 0.70-1.43 in T3, 0.75-1.45 in T4, 0.68-0.95 in T5 and 0.52-0.58 in T6. In general, in all plant growth stages, actual and relative yields decrease as relative evapotranspiration decreases.

  3. Pretreatment Growth Rate Predicts Radiation Response in Vestibular Schwannomas

    Energy Technology Data Exchange (ETDEWEB)

    Niu, Nina N. [Department of Radiation Oncology, Harvard Medical School, Massachusetts General Hospital, Boston, Massachusetts (United States); Harvard Medical School, Department of Medicine, Brigham and Women' s Hospital, Boston, Massachusetts (United States); Niemierko, Andrzej [Department of Radiation Oncology, Harvard Medical School, Massachusetts General Hospital, Boston, Massachusetts (United States); Larvie, Mykol [Harvard Medical School, Department of Radiology, Massachusetts General Hospital, Boston, Massachusetts (United States); Curtin, Hugh [Harvard Medical School, Department of Radiology, Massachusetts Eye and Ear Infirmary, Boston, Massachusetts (United States); Loeffler, Jay S. [Department of Radiation Oncology, Harvard Medical School, Massachusetts General Hospital, Boston, Massachusetts (United States); McKenna, Michael J. [Harvard Medical School, Department of Otolaryngology, Massachusetts Eye and Ear Infirmary, Boston, Massachusetts (United States); Shih, Helen A., E-mail: hshih@partners.org [Department of Radiation Oncology, Harvard Medical School, Massachusetts General Hospital, Boston, Massachusetts (United States)

    2014-05-01

    Purpose: Vestibular schwannomas (VS) are often followed without initial therapeutic intervention because many tumors do not grow and radiation therapy is associated with potential adverse effects. In an effort to determine whether maximizing initial surveillance predicts for later treatment response, the predictive value of preirradiation growth rate of VS on response to radiation therapy was assessed. Methods and Materials: Sixty-four patients with 65 VS were treated with single-fraction stereotactic radiation surgery or fractionated stereotactic radiation therapy. Pre- and postirradiation linear expansion rates were estimated using volumetric measurements on sequential magnetic resonance images (MRIs). In addition, postirradiation tumor volume change was classified as demonstrating shrinkage (ratio of volume on last follow-up MRI to MRI immediately preceding irradiation <80%), stability (ratio 80%-120%), or expansion (ratio >120%). The median pre- and postirradiation follow-up was 20.0 and 27.5 months, respectively. Seven tumors from neurofibromatosis type 2 (NF2) patients were excluded from statistical analyses. Results: In the 58 non-NF2 patients, there was a trend of correlation between pre- and postirradiation volume change rates (slope on linear regression, 0.29; P=.06). Tumors demonstrating postirradiation expansion had a median preirradiation growth rate of 89%/year, and those without postirradiation expansion had a median preirradiation growth rate of 41%/year (P=.02). As the preirradiation growth rate increased, the probability of postirradiation expansion also increased. Overall, 24.1% of tumors were stable, 53.4% experienced shrinkage, and 22.5% experienced expansion. Predictors of no postirradiation tumor expansion included no prior surgery (P=.01) and slower tumor growth rate (P=.02). The control of tumors in NF2 patients was only 43%. Conclusions: Radiation therapy is an effective treatment for VS, but tumors that grow quickly preirradiation may be

  4. Short stature in partially corrected X-linked severe combined immunodeficiency--suboptimal response to growth hormone.

    Science.gov (United States)

    De Ravin, Suk See; Shum, Elaine; Zarember, Kol A; Rezvani, Geoffrey; Rosenfeld, Ron G; Stratakis, Constantine A; Malech, Harry L

    2008-11-01

    X-linked severe combined immunodeficiency (XSCID) results from defects in the common cytokine receptor gamma chain (gamma c) required for signaling by receptors for interleukin (IL)-2, -4, -7, -9, -15, and -21. Following haploidentical bone marrow transplant without myelo-conditioning for XSCID, most patients achieve partial reconstitution often limited to T lymphocytes. Many partially corrected patients manifest extreme short stature (severe growth failure in XSCID may be related to the underlying gamma c defect. To evaluate the GH/insulin-like growth factor-I (IGF-I) axis in three children with XSCID and partial immune reconstitution with profound growth failure. The IGF-I generation test was performed by administering recombinant GH subcutaneously for 5 days, and measuring serum levels for IGF-I before GH injection, and on days 5 and 8. Study of the somatotropic axis revealed profoundly diminished IGF-I production following rGH challenge in all three patients. The data indicate that the GH/IGF-I axis in these partially corrected XSCID patients with severe short stature is profoundly impaired, and supports previous studies suggesting that the underlying gamma c defect may contribute to the severe growth failure in XSCID. This supports a role for defective gamma c in the extreme short stature of XSCID, and raises the possibility of recombinant IGF-I treatment to bypass this defect.

  5. Linking functional response and bioenergetics to estimate juvenile salmon growth in a reservoir food web

    Science.gov (United States)

    Haskell, Craig A.; Beauchamp, David A.; Bollens, Stephen M.

    2017-01-01

    Juvenile salmon (Oncorhynchus spp.) use of reservoir food webs is understudied. We examined the feeding behavior of subyearling Chinook salmon (O. tshawytscha) and its relation to growth by estimating the functional response of juvenile salmon to changes in the density of Daphnia, an important component of reservoir food webs. We then estimated salmon growth across a broad range of water temperatures and daily rations of two primary prey, Daphnia and juvenile American shad (Alosa sapidissima) using a bioenergetics model. Laboratory feeding experiments yielded a Type-II functional response curve: C = 29.858 P *(4.271 + P)-1 indicating that salmon consumption (C) of Daphnia was not affected until Daphnia densities (P) were < 30 · L-1. Past field studies documented Daphnia densities in lower Columbia River reservoirs of < 3 · L-1 in July but as high as 40 · L-1 in August. Bioenergetics modeling indicated that subyearlings could not achieve positive growth above 22°C regardless of prey type or consumption rate. When feeding on Daphnia, subyearlings could not achieve positive growth above 20°C (water temperatures they commonly encounter in the lower Columbia River during summer). At 16–18°C, subyearlings had to consume about 27,000 Daphnia · day-1 to achieve positive growth. However, when feeding on juvenile American shad, subyearlings had to consume 20 shad · day-1 at 16–18°C, or at least 25 shad · day-1 at 20°C to achieve positive growth. Using empirical consumption rates and water temperatures from summer 2013, subyearlings exhibited negative growth during July (-0.23 to -0.29 g · d-1) and August (-0.05 to -0.07 g · d-1). By switching prey from Daphnia to juvenile shad which have a higher energy density, subyearlings can partially compensate for the effects of higher water temperatures they experience in the lower Columbia River during summer. However, achieving positive growth as piscivores requires subyearlings to feed at

  6. Loss of CSL Unlocks a Hypoxic Response and Enhanced Tumor Growth Potential in Breast Cancer Cells

    Directory of Open Access Journals (Sweden)

    Eike-Benjamin Braune

    2016-05-01

    Full Text Available Notch signaling is an important regulator of stem cell differentiation. All canonical Notch signaling is transmitted through the DNA-binding protein CSL, and hyperactivated Notch signaling is associated with tumor development; thus it may be anticipated that CSL deficiency should reduce tumor growth. In contrast, we report that genetic removal of CSL in breast tumor cells caused accelerated growth of xenografted tumors. Loss of CSL unleashed a hypoxic response during normoxic conditions, manifested by stabilization of the HIF1α protein and acquisition of a polyploid giant-cell, cancer stem cell-like, phenotype. At the transcriptome level, loss of CSL upregulated more than 1,750 genes and less than 3% of those genes were part of the Notch transcriptional signature. Collectively, this suggests that CSL exerts functions beyond serving as the central node in the Notch signaling cascade and reveals a role for CSL in tumorigenesis and regulation of the cellular hypoxic response.

  7. Growth and physiological responses of some Capsicum frutescens varieties to copper stress

    Science.gov (United States)

    Jadid, Nurul; Maziyah, Rizka; Nurcahyani, Desy Dwi; Mubarokah, Nilna Rizqiyah

    2017-06-01

    Copper (Cu) is an essential micronutrient participating in various physiological processes. However, excessive uptake of this micronutrient could potentially affect plant growth and development as well as plant productivity. In this present work, growth and physiological responses of some Capsicum frustescens varieties to Cu stress were determined. Three C. frutescens varieties used in this work were var. Bara, CF 291, and Genie. In addition, these varieties were treated with different concentration of Cu (0, 30, 70, and 120 ppm). The growth and physiological responses measured in this work included plant height, root length, malondialdehyde (MDA), and chlorophyll. The result showed that all varieties tested relatively displayed plant growth reduction including plant height and root length. Likewise, an increase of MDA level, a major bioindicator for oxidative damage was also found in all varieties following exposure to elevated Cu concentration. Finally, the chlorophyll content was also affected indicated by a decreased amount of chlorophyll, especially in var. CF291. The overall results demonstrated that elevated Cu concentration might decrease C. frutescens productivity where among the three varieties tested, var CF 291 seemed to be the most sensitive varieties to Cu stress.

  8. TCP Transcription Factors at the Interface between Environmental Challenges and the Plant's Growth Responses.

    Science.gov (United States)

    Danisman, Selahattin

    2016-01-01

    Plants are sessile and as such their reactions to environmental challenges differ from those of mobile organisms. Many adaptions involve growth responses and hence, growth regulation is one of the most crucial biological processes for plant survival and fitness. The plant-specific TEOSINTE BRANCHED 1, CYCLOIDEA, PCF1 (TCP) transcription factor family is involved in plant development from cradle to grave, i.e., from seed germination throughout vegetative development until the formation of flowers and fruits. TCP transcription factors have an evolutionary conserved role as regulators in a variety of plant species, including orchids, tomatoes, peas, poplar, cotton, rice and the model plant Arabidopsis. Early TCP research focused on the regulatory functions of TCPs in the development of diverse organs via the cell cycle. Later research uncovered that TCP transcription factors are not static developmental regulators but crucial growth regulators that translate diverse endogenous and environmental signals into growth responses best fitted to ensure plant fitness and health. I will recapitulate the research on TCPs in this review focusing on two topics: the discovery of TCPs and the elucidation of their evolutionarily conserved roles across the plant kingdom, and the variety of signals, both endogenous (circadian clock, plant hormones) and environmental (pathogens, light, nutrients), TCPs respond to in the course of their developmental roles.

  9. TCP Transcription Factors at the Interface between Environmental Challenges and the Plant’s Growth Responses

    Science.gov (United States)

    Danisman, Selahattin

    2016-01-01

    Plants are sessile and as such their reactions to environmental challenges differ from those of mobile organisms. Many adaptions involve growth responses and hence, growth regulation is one of the most crucial biological processes for plant survival and fitness. The plant-specific TEOSINTE BRANCHED 1, CYCLOIDEA, PCF1 (TCP) transcription factor family is involved in plant development from cradle to grave, i.e., from seed germination throughout vegetative development until the formation of flowers and fruits. TCP transcription factors have an evolutionary conserved role as regulators in a variety of plant species, including orchids, tomatoes, peas, poplar, cotton, rice and the model plant Arabidopsis. Early TCP research focused on the regulatory functions of TCPs in the development of diverse organs via the cell cycle. Later research uncovered that TCP transcription factors are not static developmental regulators but crucial growth regulators that translate diverse endogenous and environmental signals into growth responses best fitted to ensure plant fitness and health. I will recapitulate the research on TCPs in this review focusing on two topics: the discovery of TCPs and the elucidation of their evolutionarily conserved roles across the plant kingdom, and the variety of signals, both endogenous (circadian clock, plant hormones) and environmental (pathogens, light, nutrients), TCPs respond to in the course of their developmental roles. PMID:28066483

  10. Effect of two phyto hormone producer rhizobacteria on the bermuda grass growth response and tolerance to phenanthrene

    International Nuclear Information System (INIS)

    Guerrero-Zuniga, A.; Rojas-Contreras, A.; Rodriguez-Dorantes, A.; Montes-Villafan, S.

    2009-01-01

    Plant growth-promoting rhizobacteria (PGPR) are free-living bacteria that have the ability to relieve environmental stress in plants, increasing the plant growth potential. Of importance to phytoremediation, PGPR stimulate plant root development and enhance root growth.This study evaluated the growth response and the tolerance to phenanthrene of Bermuda grass: Cynodon dactylon inoculated with two phytohormone producer rhizobacteria: strains II and III, isolated from a contaminated soil with petroleum hydrocarbons. (Author)

  11. Effect of two phyto hormone producer rhizobacteria on the bermuda grass growth response and tolerance to phenanthrene

    Energy Technology Data Exchange (ETDEWEB)

    Guerrero-Zuniga, A.; Rojas-Contreras, A.; Rodriguez-Dorantes, A.; Montes-Villafan, S.

    2009-07-01

    Plant growth-promoting rhizobacteria (PGPR) are free-living bacteria that have the ability to relieve environmental stress in plants, increasing the plant growth potential. Of importance to phytoremediation, PGPR stimulate plant root development and enhance root growth.This study evaluated the growth response and the tolerance to phenanthrene of Bermuda grass: Cynodon dactylon inoculated with two phytohormone producer rhizobacteria: strains II and III, isolated from a contaminated soil with petroleum hydrocarbons. (Author)

  12. Dose-response regressions for algal growth and similar continuous endpoints: Calculation of effective concentrations

    DEFF Research Database (Denmark)

    Christensen, Erik R.; Kusk, Kresten Ole; Nyholm, Niels

    2009-01-01

    We derive equations for the effective concentration giving 10% inhibition (EC10) with 95% confidence limits for probit (log-normal), Weibull, and logistic dose -responsemodels on the basis of experimentally derived median effective concentrations (EC50s) and the curve slope at the central point (50......% inhibition). For illustration, data from closed, freshwater algal assays are analyzed using the green alga Pseudokirchneriella subcapitata with growth rate as the response parameter. Dose-response regressions for four test chemicals (tetraethylammonium bromide, musculamine, benzonitrile, and 4...

  13. Penile growth in response to hormone treatment in children with micropenis

    OpenAIRE

    Rajendra B Nerli; Ajay Kumar Guntaka; Pravin B Patne; Murigendra B Hiremath

    2013-01-01

    Introduction: Micropenis is defined as a stretched penile length 2.5 standard deviations less than the mean for age without the presence of any other penile anomalies, such as hypospadias. The term refers to a specific disorder that has a known set of causative factors and defined treatment modalities. The purpose of this study was to determine the effect of hormonal therapy on the gonadal response and penile growth in children who presented with micropenis. Materials and Methods: Childr...

  14. Towards an integrative computational model for simulating tumor growth and response to radiation therapy

    Science.gov (United States)

    Marrero, Carlos Sosa; Aubert, Vivien; Ciferri, Nicolas; Hernández, Alfredo; de Crevoisier, Renaud; Acosta, Oscar

    2017-11-01

    Understanding the response to irradiation in cancer radiotherapy (RT) may help devising new strategies with improved tumor local control. Computational models may allow to unravel the underlying radiosensitive mechanisms intervening in the dose-response relationship. By using extensive simulations a wide range of parameters may be evaluated providing insights on tumor response thus generating useful data to plan modified treatments. We propose in this paper a computational model of tumor growth and radiation response which allows to simulate a whole RT protocol. Proliferation of tumor cells, cell life-cycle, oxygen diffusion, radiosensitivity, RT response and resorption of killed cells were implemented in a multiscale framework. The model was developed in C++, using the Multi-formalism Modeling and Simulation Library (M2SL). Radiosensitivity parameters extracted from literature enabled us to simulate in a regular grid (voxel-wise) a prostate cell tissue. Histopathological specimens with different aggressiveness levels extracted from patients after prostatectomy were used to initialize in silico simulations. Results on tumor growth exhibit a good agreement with data from in vitro studies. Moreover, standard fractionation of 2 Gy/fraction, with a total dose of 80 Gy as a real RT treatment was applied with varying radiosensitivity and oxygen diffusion parameters. As expected, the high influence of these parameters was observed by measuring the percentage of survival tumor cell after RT. This work paves the way to further models allowing to simulate increased doses in modified hypofractionated schemes and to develop new patient-specific combined therapies.

  15. Differential oxidative and antioxidative response of duckweed Lemna minor toward plant growth promoting/inhibiting bacteria.

    Science.gov (United States)

    Ishizawa, Hidehiro; Kuroda, Masashi; Morikawa, Masaaki; Ike, Michihiko

    2017-09-01

    Bacteria colonizing the plant rhizosphere are believed to positively or negatively affect the host plant productivity. This feature has inspired researchers to engineer such interactions to enhance crop production. However, it remains to be elucidated whether rhizobacteria influences plant oxidative stress vis-a-vis other environmental stressors, and whether such influence is associated with their growth promoting/inhibiting ability. In this study, two plant growth-promoting bacteria (PGPB) and two plant growth-inhibiting bacteria (PGIB) were separately inoculated into axenic duckweed (Lemna minor) culture under laboratory conditions for 4 and 8 days in order to investigate their effects on plant oxidative stress and antioxidant activities. As previously characterized, the inoculation of PGPB and PGIB strains accelerated and reduced the growth of L. minor, respectively. After 4 and 8 days of cultivation, compared to the PGPB strains, the PGIB strains induced larger amounts of O 2 •- , H 2 O 2 , and malondialdehyde (MDA) in duckweed, although all bacterial strains consistently increased O 2 •- content by two times more than that in the aseptic control plants. Activities of five antioxidant enzymes were also elevated by the inoculation of PGIB, confirming the severe oxidative stress condition in plants. These results suggest that the surface attached bacteria affect differently on host oxidative stress and its response, which degree correlates negatively to their effects on plant growth. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  16. Growth responses to elevated temperatures and the importance of ontogenetic niche shifts in Bromeliaceae.

    Science.gov (United States)

    Müller, Lilian-Lee B; Albach, Dirk C; Zotz, Gerhard

    2018-01-01

    Epiphytic bromeliads represent a major component of Neotropical forests, but the potential effect of climate change on these plants is unclear. We investigated whether and how bromeliads are affected by the predicted 3°C temperature rise by the end of the century. We conducted growth experiments with 17 epiphytic bromeliad species at different temperatures to determine their fundamental thermal niches. By comparing those with niches for germination, we tested whether ontogenetic niche shift or niche contraction occurs in Bromeliaceae. Applying a classical growth analysis, we assessed the relative importance of the underlying growth components on interspecific variations in growth. Members of two bromeliad subfamilies differed in their response to elevated temperatures: Tillandsioideae may be negatively affected, whereas Bromelioideae moved closer to their thermal optimum. Across different ontogenetic stages, thermal niche characteristics revealed both niche shift and niche contraction. Interspecific variation in growth was driven almost exclusively by net assimilation rate at all temperatures. We conclude that the vulnerability of tropical plants to a future increase in temperature may be more variable than suggested by previous studies. We emphasize the importance of assessing niche breadth over multiple life stages and the need for better microclimatic data to link laboratory data with field conditions. © 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.

  17. Effect of copper exposure on growth, condition indices and biomarker response in juvenile sole Solea senegalensis

    Directory of Open Access Journals (Sweden)

    Vanessa Fonseca

    2009-03-01

    Full Text Available Juvenile Solea senegalensis were exposed to different concentrations of waterborne copper (Cu for 15 days in static conditions with continuous aerated artificial salt water at 20°C (± 0.8°C with a normal photoperiod (10 h/14 h light/dark and daily feeding. Several measures of exposure and effects were determined: 1 biomarkers - metallothioneins and lipid peroxidation level; 2 mass indices - growth rate and morphometric condition indices; and 3 biochemical condition indices - RNA:DNA ratio and lipid and protein content in fish tissues. Copper exposure triggered the response of the biomarkers and resulted in reduced growth and condition (RNA:DNA and lipid content, but the morphometric indices did not vary. The physiological costs of Cu contamination on condition suggested that lipid reserves were allocated as an energy source to enable exposed fish to respond to Cu toxicity as well as to maintain positive growth rates and protein synthesis throughout the experiment, although with lower growth rates than the control fish. This study showed the importance of selecting suitable biomarkers according to contaminant source, fish species and their life-history stage. In addition, the use of several biomarkers of exposure, growth and specific condition indices can improve fish health determination and should be considered in evaluations of the effects of environmental contaminants on fish.

  18. Protein Crystal Growth Under Forced Solution Flow: Experimental Setup and General Response of Lysozyme

    Science.gov (United States)

    Vekilov, P. G.; Rosenberger, F.

    1998-01-01

    We have experimentally studied the effects of solution flow on the growth kinetics of the protein lysozyme. To this end, we have expanded our interferometry setup by a novel crystallization cell and solution recirculation system. This combination permits monitoring of interface morphology and kinetics with a depth resolution of 200 A at bulk flow rates of up to 2000 micron/s. Particular attention was paid to the prevention of protein denaturation that is often associated with the pumping of protein solutions. We found that at bulk flow rates it less than 250 microns/s the average growth rate and step velocity, R(sub avg) and upsilon(sub avg) increase with increasing it. This can be quantitatively understood in terms of the enhanced, convective solute supply to the interface. With high-purity solutions, it u greater than 250 microns/s lead to growth deceleration, and, at low supersaturations sigma, to growth cessation. When solutions containing approx. 1% of other protein impurities were used, growth deceleration occurred at any u greater than 0 and cessation in the low sigma experiments was reached at about half the it causing cessation with pure solution. The flow-induced changes in R(sub avg) and upsilon(sub avg) including growth cessation, were reversible and reproducible, independent of the direction of the u-changes and solution purity. Hence, we attribute the deceleration to the convection-enhanced supply of impurities to the interface, which at higher flow rates overpowers the effects of enhanced interfacial solute concentration. Most importantly, we found that convective transport leads to a significant reduction in kinetics fluctuations, in agreement with our earlier expectations for the lysozyme system. This supports our hypothesis that these long-term fluctuations represent an intrinsic response feature of the coupled bulk transport-interfacial kinetics system in the mixed growth control regime.

  19. Early vs. asymptotic growth responses of herbaceous plants to elevated CO[sub 2

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, S.C.; Jasienski, M.; Bazzaz, F.A. (Harvard Univ., Cambridge, MA (United States). Dept. of Organismic and Evolutionary Biology)

    1999-07-01

    Although many studies have examined the effects of elevated carbon dioxide on plant growth,'' the dynamics of growth involve at least two parameters, namely, an early rate of exponential size increase and an asymptotic size reached late in plant ontogeny. The common practice of quantifying CO[sub 2] responses as a single response ratio thus obscures two qualitatively distinct kinds of effects. The present experiment examines effects of elevated CO[sub 2] on both early and asymptotic growth parameters in eight C[sub 3] herbaceous plant species (Abutilon theophrasti, Cassia obtusifolia, Plantago major, Rumex crispus, Taraxacum officinale, Dactylis glomerata, Lolium multiflorum, and Panicum dichotomoflorum). Plants were grown for 118--172 d in a factorial design of CO[sub 2] (350 and 700 [micro]L/L) and plant density (individually grown vs. high-density monocultures) under edaphic conditions approximating those of coastal areas in Massachusetts. For Abutilon theophrasti, intraspecific patterns of plant response were also assessed using eight genotypes randomly sampled from a natural population and propagated as inbred lines.

  20. Trade-Offs in Arbuscular Mycorrhizal Symbiosis: Disease Resistance, Growth Responses and Perspectives for Crop Breeding

    Directory of Open Access Journals (Sweden)

    Catherine N. Jacott

    2017-11-01

    Full Text Available There is an increasing need to develop high-yielding, disease-resistant crops and reduce fertilizer usage. Combining disease resistance with efficient nutrient assimilation through improved associations with symbiotic microorganisms would help to address this. Arbuscular mycorrhizal fungi (AMF form symbiotic relationships with most terrestrial plants, resulting in nutritional benefits and the enhancement of stress tolerance and disease resistance. Despite these advantages, arbuscular mycorrhizal (AM interactions are not normally directly considered in plant breeding. Much of our understanding of the mechanisms of AM symbiosis comes from model plants, which typically exhibit positive growth responses. However, applying this knowledge to crops has not been straightforward. In many crop plants, phosphate uptake and growth responses in AM-colonized plants are variable, with AM plants exhibiting sometimes zero or negative growth responses and lower levels of phosphate acquisition. Host plants must also balance the ability to host AMF with the ability to resist pathogens. Advances in understanding the plant immune system have revealed similarities between pathogen infection and AM colonization that may lead to trade-offs between symbiosis and disease resistance. This review considers the potential trade-offs between AM colonization, agronomic traits and disease resistance and highlights the need for translational research to apply fundamental knowledge to crop improvement.

  1. Maize maintains growth in response to decreased nitrate supply through a highly dynamic and developmental stage-specific transcriptional response

    KAUST Repository

    Plett, Darren

    2015-06-02

    Elucidation of the gene networks underlying the response to N supply and demand will facilitate the improvement of the N uptake efficiency of plants. We undertook a transcriptomic analysis of maize to identify genes responding to both a non-growth-limiting decrease in NO3- provision and to development-based N demand changes at seven representative points across the life cycle. Gene co-expression networks were derived by cluster analysis of the transcript profiles. The majority of NO3--responsive transcription occurred at 11 (D11), 18 (D18) and 29 (D29) days after emergence, with differential expression predominating in the root at D11 and D29 and in the leaf at D18. A cluster of 98 probe sets was identified, the expression pattern of which is similar to that of the high-affinity NO3- transporter (NRT2) genes across the life cycle. The cluster is enriched with genes encoding enzymes and proteins of lipid metabolism and transport, respectively. These are candidate genes for the response of maize to N supply and demand. Only a few patterns of differential gene expression were observed over the entire life cycle; however, the composition of the classes of the genes differentially regulated at individual time points was unique, suggesting tightly controlled regulation of NO3--responsive gene expression. © 2015 Society for Experimental Biology, Association of Applied Biologists and John Wiley & Sons Ltd.

  2. Development temperature has persistent effects on muscle growth responses in gilthead sea bream.

    Directory of Open Access Journals (Sweden)

    Daniel Garcia de la serrana

    Full Text Available Initially we characterised growth responses to altered nutritional input at the transcriptional and tissue levels in the fast skeletal muscle of juvenile gilthead sea bream. Fish reared at 21-22°C (range were fed a commercial diet at 3% body mass d(-1 (non-satiation feeding, NSF for 4 weeks, fasted for 4d (F and then fed to satiation (SF for 21d. 13 out of 34 genes investigated showed consistent patterns of regulation between nutritional states. Fasting was associated with a 20-fold increase in MAFbx, and a 5-fold increase in Six1 and WASp expression, which returned to NSF levels within 16h of SF. Refeeding to satiation was associated with a rapid (<24 h 12 to 17-fold increase in UNC45, Hsp70 and Hsp90α transcripts coding for molecular chaperones associated with unfolded protein response pathways. The growth factors FGF6 and IGF1 increased 6.0 and 4.5-fold within 16 h and 24 h of refeeding respectively. The average growth in diameter of fast muscle fibres was checked with fasting and significant fibre hypertrophy was only observed after 13d and 21d SF. To investigate developmental plasticity in growth responses we used the same experimental protocol with fish reared at either 17.5-18.5°C (range (LT or 21-22°C (range (HT to metamorphosis and then transferred to 21-22°C. There were persistent effects of development temperature on muscle growth patterns with 20% more fibres of lower average diameter in LT than HT group of similar body size. Altering the nutritional input to the muscle to stimulate growth revealed cryptic changes in the expression of UNC45 and Hsp90α with higher transcript abundance in the LT than HT groups, whereas there were no differences in the expression of MAFbx and Six1. It was concluded that myogenesis and gene expression patterns during growth are not fixed, but can be modified by temperature during the early stages of the life cycle.

  3. Growth and Photosynthetic Responses to Salinity of the Salt-marsh Shrub Atriplex portulacoides

    Science.gov (United States)

    Redondo-Gómez, Susana; Mateos-Naranjo, Enrique; Davy, Anthony J.; Fernández-Muñoz, Francisco; Castellanos, Eloy M.; Luque, Teresa; Figueroa, M. Enrique

    2007-01-01

    Background and Aims Atriplex (Halimione) portulacoides is a halophytic, C3 shrub. It is virtually confined to coastal salt marshes, where it often dominates the vegetation. The aim of this study was to investigate its growth responses to salinity and the extent to which these could be explained by photosynthetic physiology. Methods The responses of young plants to salinity in the range 0–700 mol m−3 NaCl were investigated in a glasshouse experiment. The performance of plants was examined using classical growth analysis, measurements of gas exchange (infrared gas analysis), determination of chlorophyll fluorescence characteristics (modulated fluorimeter) and photosynthetic pigment concentrations; total ash, sodium, potassium and nitrogen concentrations, and relative water content were also determined. Key Results Plants accumulated Na+ approximately in proportion to external salinity. Salt stimulated growth up to an external concentration of 200 mol m−3 NaCl and some growth was maintained at higher salinities. The main determinant of growth response to salinity was unit leaf rate. This was itself reflected in rates of CO2 assimilation, which were not affected by 200 mol m−3 but were reduced at higher salinities. Reductions in net photosynthetic rate could be accounted for largely by lower stomatal conductance and intercellular CO2 concentration. Apart from possible effects of osmotic shock at the beginning of the experiment, salinity did not have any adverse effect on photosystem II (PSII). Neither the quantum efficiency of PSII (ΦPSII) nor the chlorophyll fluorescence ratio (Fv/Fm) were reduced by salinity, and lower mid-day values recovered by dawn. Mid-day Fv/Fm was in fact depressed more at low external sodium concentration, by the end of the experiment. Conclusions The growth responses of the hygro-halophyte A. portulacoides to salinity appear largely to depend on changes in its rate of photosynthetic gas exchange. Photosynthesis appears to be limited

  4. Divergence between growth hormone responses to insulin-induced hypoglycaemia and growth hormone-releasing hormone in patients with non-functioning pituitary macroadenomas and hyperprolactinaemia

    NARCIS (Netherlands)

    Beentjes, JAM; Sluiter, WJ; Dullaart, RPF

    1996-01-01

    OBJECTIVE The GH responses to the insulin tolerance test (ITT) and growth hormone-releasing hormone (GHRH) may yield different results in patients with pituitary lesions. The GH responses to these stimuli were compared in patients with untreated non-functioning pituitary macroadenomas, who represent

  5. Does fungal endophyte infection improve tall fescue's growth response to fire and water limitation?

    Directory of Open Access Journals (Sweden)

    Sarah L Hall

    Full Text Available Invasive species may owe some of their success in competing and co-existing with native species to microbial symbioses they are capable of forming. Tall fescue is a cool-season, non-native, invasive grass capable of co-existing with native warm-season grasses in North American grasslands that frequently experience fire, drought, and cold winters, conditions to which the native species should be better-adapted than tall fescue. We hypothesized that tall fescue's ability to form a symbiosis with Neotyphodium coenophialum, an aboveground fungal endophyte, may enhance its environmental stress tolerance and persistence in these environments. We used a greenhouse experiment to examine the effects of endophyte infection (E+ vs. E-, prescribed fire (1 burn vs. 2 burn vs. unburned control, and watering regime (dry vs. wet on tall fescue growth. We assessed treatment effects for growth rates and the following response variables: total tiller length, number of tillers recruited during the experiment, number of reproductive tillers, tiller biomass, root biomass, and total biomass. Water regime significantly affected all response variables, with less growth and lower growth rates observed under the dry water regime compared to the wet. The burn treatments significantly affected total tiller length, number of reproductive tillers, total tiller biomass, and total biomass, but treatment differences were not consistent across parameters. Overall, fire seemed to enhance growth. Endophyte status significantly affected total tiller length and tiller biomass, but the effect was opposite what we predicted (E->E+. The results from our experiment indicated that tall fescue was relatively tolerant of fire, even when combined with dry conditions, and that the fungal endophyte symbiosis was not important in governing this ecological ability. The persistence of tall fescue in native grassland ecosystems may be linked to other endophyte-conferred abilities not measured here

  6. Hypoxia inhibits growth, proliferation, and increases response to chemotherapy in retinoblastoma cells.

    Science.gov (United States)

    Yang, Qian; Tripathy, Arushi; Yu, Wayne; Eberhart, Charles G; Asnaghi, Laura

    2017-09-01

    Retinoblastoma is a malignant tumor of the retina and the most frequent intraocular cancer in children. Low oxygen tension (hypoxia) is a common phenomenon in advanced retinoblastomas, but its biological effect on retinoblastoma growth is not clearly understood. Here we studied how hypoxia altered retinoblastoma gene expression and modulated growth and response to chemotherapy. The hypoxic marker lysyl oxidase (LOX) was expressed in 8 of 12 human retinoblastomas analyzed by immunohistochemistry, suggesting that a hypoxic microenvironment is present in up to two thirds of the cases. WERI Rb1 and Y79 retinoblastoma lines were exposed to 1% or 5% pO 2 , cobalt chloride (CoCl 2 ), or to normoxia (21% pO 2 ) for up to 8 days. Both 1% and 5% pO 2 inhibited growth of both lines by more than 50%. Proliferation was reduced by 25-50% when retinoblastoma cells were exposed to 1% vs 21% pO 2 , as determined by Ki67 assay. Surprisingly, Melphalan, Carboplatin, and Etoposide produced greater reduction in growth and survival of hypoxic cells than normoxic ones. Gene expression profile analysis of both lines, exposed for 48 h to 1%, 5%, or 21% pO 2 , showed that glycolysis and glucose transport were the most up-regulated pathways, whereas oxidative phosphorylation was the most down-regulated pathway in hypoxia as compared to normoxia. These data support a role for hypoxia in suppressing growth, proliferation, and enhancing response of retinoblastoma cells to chemotherapy, possibly by impairing energy production through activation of glycolysis and inhibition of mitochondrial respiration. Targeting glucose metabolism or enhancing delivery of chemotherapeutic agents to hypoxic regions may improve treatment of advanced retinoblastomas. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Response to growth hormone treatment and final height after cranial or craniospinal irradiation

    International Nuclear Information System (INIS)

    Sulmont, V.; Brauner, R.; Fontoura, M.; Rappaport, R.

    1990-01-01

    Growth hormone (GH) deficiency (GHD) induced by cranial irradiation has become a frequent indication of hGH substitutive therapy. This study analyses the growth response to hGH therapy and the factors involved in the decrease in growth velocity observed after cranial irradiation. One hundred children given cranial radiation for pathology distant from the hypothalamo-pituitary area were studied. Fifty-six of them received hGH therapy for GHD resulting in decreased growth velocity. The initial annual height gain in the cranial-irradiated group was comparable to that of patients treated for idiopathic GHD; additional spinal irradiation significantly reduced the growth response. Twenty-eight hGH-treated patients reached final heights which were compared to those of 2 untreated irradiated groups, one with GHD (n=27) and the other with normal GH secretion (n=17). The height SD score changes observed in hGH therapy were +0.3 in the cranial (n=10) and -1.2 SD in the craniospinal (n=18) groups. GH deficiency had contributed to a mean height loss of 1 SD and spinal irradiation to a loss of 1.4SD. The small effect of hGH therapy on final height is probably linked to the small bone age retardation at onset of hGH therapy and to the fact that irradiated children entered puberty at a younger age in terms of chronological age and bone age than the idiopathic GHD patients. These data suggest that the results of gGH therapy in irradiated children might be improved with higher and more fractionated hGH doses and, in some patients, by delaying puberty using luteinizing hormone releasing hormone analogs

  8. Coupled dynamics of energy budget and population growth of tilapia in response to pulsed waterborne copper.

    Science.gov (United States)

    Chen, Wei-Yu; Lin, Chia-Jung; Ju, Yun-Ru; Tsai, Jeng-Wei; Liao, Chung-Min

    2012-11-01

    The impact of environmentally pulsed metal exposure on population dynamics of aquatic organisms remains poorly understood and highly unpredictable. The purpose of our study was to link a dynamic energy budget model to a toxicokinetic/toxicodynamic (TK/TD). We used the model to investigate tilapia population dynamics in response to pulsed waterborne copper (Cu) assessed with available empirical data. We mechanistically linked the acute and chronic bioassays of pulsed waterborne Cu at the scale of individuals to tilapia populations to capture the interaction between environment and population growth and reproduction. A three-stage matrix population model of larva-juvenile-adult was used to project offspring production through two generations. The estimated median population growth rate (λ) decreased from 1.0419 to 0.9991 under pulsed Cu activities ranging from 1.6 to 2.0 μg L(-1). Our results revealed that the influence on λ was predominately due to changes in the adult survival and larval survival and growth functions. We found that pulsed timing has potential impacts on physiological responses and population abundance. Our study indicated that increasing time intervals between first and second pulses decreased mortality and growth inhibition of tilapia populations, indicating that during long pulsed intervals tilapia may have enough time to recover. Our study concluded that the bioenergetics-based matrix population methodology could be employed in a life-cycle toxicity assessment framework to explore the effect of stage-specific mode-of-actions in population response to pulsed contaminants.

  9. Global responses of Methanococcus maripaludis to specific nutrient limitations and growth rate.

    Science.gov (United States)

    Hendrickson, Erik L; Liu, Yuchen; Rosas-Sandoval, Guillermina; Porat, Iris; Söll, Dieter; Whitman, William B; Leigh, John A

    2008-03-01

    Continuous culture, transcriptome arrays, and measurements of cellular amino acid pools and tRNA charging levels were used to determine the response of Methanococcus maripaludis to leucine limitation. For comparison, the responses to phosphate and H2 limitations were measured as well. In addition, the effect of growth rate was determined. Leucine limitation resulted in a broad response. tRNA(Leu) charging decreased, but only small increases in mRNA were seen for amino acid biosynthesis genes. However, the cellular levels of free isoleucine and valine showed significant increases, indicating a coordinate regulation of branched-chain amino acids at a post-mRNA level. Leucine limitation also resulted in increased mRNA abundance for ribosomal protein genes, increased rRNA abundance, and decreased mRNA abundance for genes of methanogenesis. In contrast, phosphate limitation induced a specific response, a marked increase in mRNA levels for a phosphate transporter. Some mRNA levels responded to more than one factor; for example, transcripts for flagellum synthesis genes decreased under conditions of leucine limitation and increased under H2 limitation. Increased growth rate resulted in increased mRNA levels for ribosomal protein genes, increased rRNA abundance, and increased mRNA for a gene encoding an S-layer protein.

  10. Heterologous humoral immune response in patients treated with human growth hormone from different sources

    Energy Technology Data Exchange (ETDEWEB)

    Cardoso, A.I.; Llera, A.S.; Iacono, R.F. (and others) (Inst. de Estudios de la Inmunidad Humoral, Buenos Aires (Argentina))

    1993-07-01

    The existence of homologous anti-human growth hormone (anti-hGH) and heterologous anti-bovine growth hormone (anti-bGH) humoral immune responses in hypopituitary patients under hGH therapy has been reported previously. In order to study the influence of the hormone source, both responses were compared by radiobinding assays performed with [[sup 125]I]hGH or [[sup 125]I]bGH as tracers. 57 hypopituitary patients treated with extractive hGH, recombinant methionyl hGH or authentic recombinant hGH were studied. A very low incidence of heterologous antibodies was found in patients under recombinant hGH therapy, contrary to the high incidence observed in patients treated with extractive hGH preparations. In addition, immunochemical studies performed with a synthetic peptide (hGH 44-128) indicated that this peptide exhibited, in the anti-bGH/[[sup 125]I]bGH radioimmunoassay system, higher reactivity than the native hGH, suggesting that such fragment resembled an altered conformation of the hormone. The high heterologous response elicited only by the extractive hGH along with the behaviour of the hGH 44-128 fragment supports the fact that the extraction and purification procedures in extractive preparations may alter slightly the structure of the hGH molecule and trigger a heterologous immune response. 16 refs., 4 figs., 1 tab.

  11. Heterologous humoral immune response in patients treated with human growth hormone from different sources

    International Nuclear Information System (INIS)

    Cardoso, A.I.; Llera, A.S.; Iacono, R.F.

    1993-01-01

    The existence of homologous anti-human growth hormone (anti-hGH) and heterologous anti-bovine growth hormone (anti-bGH) humoral immune responses in hypopituitary patients under hGH therapy has been reported previously. In order to study the influence of the hormone source, both responses were compared by radiobinding assays performed with [ 125 I]hGH or [ 125 I]bGH as tracers. 57 hypopituitary patients treated with extractive hGH, recombinant methionyl hGH or authentic recombinant hGH were studied. A very low incidence of heterologous antibodies was found in patients under recombinant hGH therapy, contrary to the high incidence observed in patients treated with extractive hGH preparations. In addition, immunochemical studies performed with a synthetic peptide (hGH 44-128) indicated that this peptide exhibited, in the anti-bGH/[ 125 I]bGH radioimmunoassay system, higher reactivity than the native hGH, suggesting that such fragment resembled an altered conformation of the hormone. The high heterologous response elicited only by the extractive hGH along with the behaviour of the hGH 44-128 fragment supports the fact that the extraction and purification procedures in extractive preparations may alter slightly the structure of the hGH molecule and trigger a heterologous immune response. 16 refs., 4 figs., 1 tab

  12. Comparison between the growth response to growth hormone (GH) therapy in children with partial GH insensitivity or mild GH deficiency.

    Science.gov (United States)

    Cardoso, Daniela F; Martinelli, Carlos Eduardo; Campos, Viviane C; Gomes, Elenilde S; Rocha, Ivina E S; Oliveira, Carla R P; Vicente, Taisa A R; Pereira, Rossana M C; Pereira, Francisco A; Cartaxo, Carla K A; Milani, Soraya L S; Oliveira, Mario C P; Melo, Enaldo V; Oliveira, Andre L P; Aguiar-Oliveira, Manuel H

    2014-02-01

    GH therapy is still controversial, except in severe GH deficiency (SGHD). The objective of this study was to compare the response to growth hormone (GH) therapy in children with partial GH insensitivity (PGHIS) and mild GH deficiency (MGHD) with those with SGHD. Fifteen PGHIS, 11 MGHD, and 19 SGHD subjects, followed up for more than one year in the Brazilian public care service, were evaluated regarding anthropometric and laboratory data at the beginning of treatment, after one year (1st year) on treatment, and at the last assessment (up to ten years in SGHD, up to four years in MGHD, and up to eight years in PGHIS). Initial height standard deviation score (SDS) in SGHD was lower than in MGHD and PGHIS. Although the increase in 1 st year height SDS in comparison to initial height SDS was not different among the groups, height-SDS after the first year of treatment remained lower in SGHD than in MGHD. There was no difference in height-SDS at the last assessment of the children among the three groups. GH therapy, in the entire period of observation, caused a trend towards lower increase in height SDS in PGHIS than SGHD but similar increases were observed in MGHD and SGHD. GH therapy increases height in PGHIS and produces similar height effects in MGHD and SGHD.

  13. Effect of fat supplementation on leptin, insulin-like growth factor I, growth hormone, and insulin in cattle

    OpenAIRE

    Becú-Villalobos, Damasia; García-Tornadú, Isabel; Shroeder, Guillermo; Salado, Eloy E.; Gagliostro, Gerardo; Delavaud, Carole; Chilliard, Yves; Lacau-Mengido, Isabel M.

    2007-01-01

    We investigated the effect of fat supplementation on plasma levels of hormones related to metabolism, with special attention to leptin, in cows in early lactation and in feedlot steers. In experiment 1, 34 lactating cows received no fat or else 0.5 or 1.0 kg of partially hydrogenated oil per day in addition to their basal diet from day 20 before the expected calving date to day 70 postpartum. In experiment 2, part of the corn in the basal concentrate was replaced with 0.7 kg of the same oil s...

  14. Timing of Drought Triggers Distinct Growth Responses in Holm Oak: Implications to Predict Warming-Induced Forest Defoliation and Growth Decline

    Directory of Open Access Journals (Sweden)

    J. Julio Camarero

    2015-05-01

    Full Text Available Droughts negatively impact forests by reducing growth and increasing defoliation leading to forest dieback as the climate becomes warmer and drier. However, the timing and severity of droughts determine how differently or intensively water shortage affects primary (shoot and leaf formation and secondary growth (stem radial growth based on tree-ring widths. We compare the impact of two severe droughts (2005, 2012, showing different climatic characteristics on the growth responses of three Mediterranean holm oak stands in northeastern Spain. We also quantify climate trends and drought severity. Then, we use remote sensing data to infer how those droughts impacted forest productivity. Both droughts were characterized by warm and dry spring conditions leading to reduced budburst, low shoot production, asynchrony in primary growth and decreased productivity and scarce radial growth, particularly in 2005. However, defoliation peaked in 2012 when radial growth showed minimum values and early spring and late summer temperatures reached maximum values. We discuss how uncoupled and resilient are the responses of primary and secondary growth to drought. Finally, these findings are used to gain insight into the drought-related drivers of defoliation in Spanish holm oak forests.

  15. Thermal Responses of Growth and Toxin Production in Four Prorocentrum Species from the Central Red Sea

    KAUST Repository

    Aynousah, Arwa

    2017-06-01

    Harmful algae studies, in particular toxic dinoflagellates, and their response to global warming in the Red Sea are still limited. This study was aimed to be the first to characterize the identity, thermal responses and toxin production of four Prorocentrum strains isolated from the Central Red Sea, Saudi Arabia. Morphological and molecular phylogenetic analysis identified the strains as P. elegans, P. rhathymum and P. emarginatum. However, the identity of strain P. sp.6 is currently unresolved, albeit sharing close affinity with P. leve. Growth experiments showed that all species could grow at 24-32°C, but only P. sp.6 survived the 34°C treatment. The optimum temperatures (Topt) estimated from the Gaussian model corresponded to 27.17, 29.33, 26.87, and 27.64°C for P. sp.6, P. elegans, P. rhathymum and P. emarginatum, respectively. However, some discrepancy with the Topt derived from the growth performance were observed for P. elegans and P. emarginatum, as thermal responses differed from the typical Gaussian fit. The Prorocentrum species examined showed a sharp decrease after the optimum temperature resulting in very high activation energies for the fall slope, especially for P. elegans and P. emarginatum. The minimum critical temperature limit for growth was not detected within the range of temperatures examined. Subsequently, high performance liquid chromatography coupled with mass spectrometry (HPLC-MS) analysis revealed all species as non okadaic acid (OA, common toxin of the Prorocentrum genus) producers at any temperature treatment. However, other forms of toxin (i.e. fast acting toxins) not examined here could be produced. Therefore, further investigations are required. The results of this study provided significant contribution to our knowledge regarding the presence, thermal response and toxin production of four Prorocentrum species from the Central Red Sea, Saudi Arabia.

  16. First-year response to rhGH therapy in children with CKD: a National Cooperative Growth Study Report.

    Science.gov (United States)

    Mahan, John D; Warady, Bradley A; Frane, James; Rosenfeld, Ron G; Swinford, Rita D; Lippe, Barbara; Davis, D Aaron

    2010-06-01

    A clear definition of the appropriate growth response during recombinant human growth hormone (rhGH) treatment has never been established in the pediatric chronic kidney disease (CKD) population. We present here data from Genentech's National Cooperative Growth Study (NCGS) on the first-year growth response in prepubertal children with CKD. Using NCGS data, we constructed response curves for the first year of rhGH therapy in 270 (186 males, 84 females) naïve-to-treatment, prepubertal children with CKD prior to transplant or dialysis. Data from both genders were combined because gender was not significantly related to height velocity (p = 0.51). Response to rhGH was expressed as height velocity (HV) in cm/year. Mean, mean + or - 1SD, and mean - 2SD for HV during the first year of rhGH treatment as well as pretreatment HV were plotted versus age. Age-specific HV plots for rhGH-treated children with CKD are presented. At all ages, the first-year mean HV was greater than the mean pretreatment HV. The mean - 2SD for HV in children on rhGH treatment was similar to the mean pretreatment HV. These growth plots will be useful to clinicians for assessing a patient's first-year growth response. We propose that a HV below the mean - 1SD is an inadequate response. These curves may help identify patients with a suboptimal growth response due to confounding medical factors and/or non-compliance.

  17. Transcriptional responses of three model diatoms to nitrate limitation of growth

    Directory of Open Access Journals (Sweden)

    Sara J Bender

    2014-03-01

    Full Text Available Diatoms are among the most diverse groups of phytoplankton in the ocean. Despite their widely recognized influence on ocean ecosystems and global biogeochemistry, little is known about the impact of this diversity on large-scale processes. Here, we examined the ramifications of between-species diversity by documenting the transcriptional response of three diatoms - Thalassiosira pseudonana, Fragilariopsis cylindrus, and Pseudo-nitzschia multiseries - to the onset of nitrate limitation of growth, a common limiting nutrient in the ocean. The three species shared 5,583 clusters of orthologous genes based on OrthoMCL clustering of publically available diatom genomes. These clusters represent 30-54% of the predicted genes in each diatom genome. Less than 5% of genes within these core clusters displayed the same transcriptional responses across species when growth was limited by nitrate availability. Orthologs, such as those involved in nitrogen uptake and assimilation, as well as carbon metabolism, were differently expressed across the three species. The two pennate diatoms, F. cylindrus and P. multiseries, shared 3,839 clusters without orthologs in the genome of the centric diatom T. pseudonana. A majority of these pennate-clustered genes, as well as the non-orthologous genes in each species, had minimal annotation information, but were often significantly differentially expressed under nitrate limitation, indicating their potential importance in the response to nitrogen availability. Despite these variations in the specific transcriptional response of each diatom, overall transcriptional patterns suggested that all three diatoms displayed a common physiological response to nitrate limitation that consisted of a general reduction in carbon fixation and carbohydrate and fatty acid metabolism and an increase in nitrogen recycling. Characterization of these finely tuned responses will help to better predict which types of diatoms will bloom under which

  18. Fern Stomatal Responses to ABA and CO2Depend on Species and Growth Conditions.

    Science.gov (United States)

    Hõrak, Hanna; Kollist, Hannes; Merilo, Ebe

    2017-06-01

    Changing atmospheric CO 2 levels, climate, and air humidity affect plant gas exchange that is controlled by stomata, small pores on plant leaves and stems formed by guard cells. Evolution has shaped the morphology and regulatory mechanisms governing stomatal movements to correspond to the needs of various land plant groups over the past 400 million years. Stomata close in response to the plant hormone abscisic acid (ABA), elevated CO 2 concentration, and reduced air humidity. Whether the active regulatory mechanisms that control stomatal closure in response to these stimuli are present already in mosses, the oldest plant group with stomata, or were acquired more recently in angiosperms remains controversial. It has been suggested that the stomata of the basal vascular plants, such as ferns and lycophytes, close solely hydropassively. On the other hand, active stomatal closure in response to ABA and CO 2 was found in several moss, lycophyte, and fern species. Here, we show that the stomata of two temperate fern species respond to ABA and CO 2 and that an active mechanism of stomatal regulation in response to reduced air humidity is present in some ferns. Importantly, fern stomatal responses depend on growth conditions. The data indicate that the stomatal behavior of ferns is more complex than anticipated before, and active stomatal regulation is present in some ferns and has possibly been lost in others. Further analysis that takes into account fern species, life history, evolutionary age, and growth conditions is required to gain insight into the evolution of land plant stomatal responses. © 2017 American Society of Plant Biologists. All Rights Reserved.

  19. Growth and physiological responses of maize (Zea mays L.) to porous silica nanoparticles in soil

    Energy Technology Data Exchange (ETDEWEB)

    Suriyaprabha, R.; Karunakaran, G.; Yuvakkumar, R.; Prabu, P.; Rajendran, V., E-mail: veerajendran@gmail.com [K. S. Rangasamy College of Technology, Centre for Nano Science and Technology (India); Kannan, N. [K. S. Rangasamy College of Arts and Science, Department of Biotechnology (India)

    2012-12-15

    The present study aims to explore the effect of high surface area (360.85 m{sup 2} g{sup -1}) silica nanoparticles (SNPs) (20-40 nm) extracted from rice husk on the physiological and anatomical changes during maize growth in sandy loam soil at four concentrations (5-20 kg ha{sup -1}) in comparison with bulk silica (15-20 kg ha{sup -1}). The plant responses to nano and bulk silica treatments were analyzed in terms of growth characteristics, phyto compounds such as total protein, chlorophyll, and other organic compounds (gas chromatography-mass spectroscopy), and silica accumulation (high-resolution scanning electron microscopy). Growth characteristics were much influenced with increasing concentration of SNPs up to 15 kg ha{sup -1} whereas at 20 kg ha{sup -1}, no significant increments were noticed. Silica accumulation in leaves was high at 10 and 15 kg ha{sup -1} (0.57 and 0.82 %) concentrations of SNPs. The observed physiological changes show that the expression of organic compounds such as proteins, chlorophyll, and phenols favored to maize treated with nanosilica especially at 15 kg ha{sup -1} compared with bulk silica and control. Nanoscale silica regimes at 15 kg ha{sup -1} has a positive response of maize than bulk silica which help to improve the sustainable farming of maize crop as an alternative source of silica fertilizer.

  20. Genotypic Differences in Growth and Physiological Responses to Transplanting and Direct Seeding Cultivation in Rice

    Directory of Open Access Journals (Sweden)

    Song Chen

    2009-06-01

    Full Text Available The field experiments were conducted to investigate the growth and physiological responses of six super hybrid rice combinations to two planting methods, transplanting (TP and direct seeding (DS during 2006–2007 and 2007–2008. The 1000-grain weight and number of tillers per plant at the early growth stage, the maximum quantum yield of PSII (Fv/Fm and transpiration rate (Tr were higher in DS plants than in TP ones, whereas the grain yield, number of panicles per square meter, seed setting rate, net photosynthetic rate (Pn and stomatal conductance were lower in DS plants. However, little difference was detected in number of grains per panicle, stem (shoot and leaf weight between the combinations in the two planting methods. The responses of plant growth and physiological traits to planting method differed greatly among the six combinations. In both planting methods, Chouyou 58 and Yongyou 6 had the highest and lowest panicle biomass and Pn, respectively. The higher yield of Chunyou 58 was associated with more numbers of panicles per square meter and grains per panicle in both planting methods. The results indicate that lower grain yield in DS relative to TP is attributed to more excessive tillers at the early stage, lower leaf biomass and photosynthetic rate at the late stage.

  1. Growth responses of maritime sand dune plant species to arbuscular mycorrhizal fungi

    Directory of Open Access Journals (Sweden)

    Mariusz Tadych

    2014-08-01

    Full Text Available In a pot experiment conducted in a greenhouse, the response of 6 plant species dominating in the succession of vegetation of a deflation hollow of the Łeba Bar to inoculation with arbuscular mycorrhizal fungi (AMF was investigated. The inoculum was a mixture of soil, roots and spores of 5 species of AMF with the dominant species Glomus aggregatum. Except for Corynephorus canescens and Festuca rubra subsp. arenaria, both the growth and the dry matter of above-ground parts of plants of Agrostis stolonifera, Ammophila arenaria, Corynephorus canescens, Juncus articulatus and J. balticus inoculated with AMF were higher than those growing in soils lacking infection propagules of these fungi. Inoculation with AMF decreased the dry matter of root: shoot ratios in 5 plant species. This property was not determined in Festuca rubra subsp. arenaria due to the death of all control plants. The level of mycorrhizal infection was low and did not correlate with the growth responses found. The high growth reaction of Juncus spp. to AMF found in this study suggests that the opinion of non-mycotrophy or low dependence of plants of Juncaceae on AMF was based on results of investigations of plants growing in wet sites known to inhibit the formation of mycorrhizae.

  2. Responses of crop yield growth to global temperature and socioeconomic changes.

    Science.gov (United States)

    Iizumi, Toshichika; Furuya, Jun; Shen, Zhihong; Kim, Wonsik; Okada, Masashi; Fujimori, Shinichiro; Hasegawa, Tomoko; Nishimori, Motoki

    2017-08-10

    Although biophysical yield responses to local warming have been studied, we know little about how crop yield growth-a function of climate and technology-responds to global temperature and socioeconomic changes. Here, we present the yield growth of major crops under warming conditions from preindustrial levels as simulated by a global gridded crop model. The results revealed that global mean yields of maize and soybean will stagnate with warming even when agronomic adjustments are considered. This trend is consistent across socioeconomic assumptions. Low-income countries located at low latitudes will benefit from intensive mitigation and from associated limited warming trends (1.8 °C), thus preventing maize, soybean and wheat yield stagnation. Rice yields in these countries can improve under more aggressive warming trends. The yield growth of maize and soybean crops in high-income countries located at mid and high latitudes will stagnate, whereas that of rice and wheat will not. Our findings underpin the importance of ambitious climate mitigation targets for sustaining yield growth worldwide.

  3. Neural Responses to Injury: Prevention, Protection and Repair; Volume 7: Role Growth Factors and Cell Signaling in the Response of Brain and Retina to Injury

    National Research Council Canada - National Science Library

    Bazan, Nicolas

    1996-01-01

    ...: Prevention, Protection, and Repair, Subproject: Role of Growth Factors and Cell Signaling in the Response of Brain and Retina to Injury, are as follows: Species Rat(Albino Wistar), Number Allowed...

  4. Multiple phosphorylation events control chicken ovalbumin upstream promoter transcription factor I orphan nuclear receptor activity.

    Science.gov (United States)

    Gay, Frédérique; Baráth, Peter; Desbois-Le Péron, Christine; Métivier, Raphaël; Le Guével, Rémy; Birse, Darcy; Salbert, Gilles

    2002-06-01

    Chicken ovalbumin upstream promoter transcription factor I (COUP-TFI) is an orphan member of the nuclear hormone receptor superfamily that comprises key regulators of many biological functions, such as embryonic development, metabolism, homeostasis, and reproduction. Although COUP-TFI can both actively silence gene transcription and antagonize the functions of various other nuclear receptors, the COUP-TFI orphan receptor also acts as a transcriptional activator in certain contexts. Moreover, COUP-TFI has recently been shown to serve as an accessory factor for some ligand-bound nuclear receptors, suggesting that it may modulate, both negatively and positively, a wide range of hormonal responses. In the absence of any identified cognate ligand, the mechanisms involved in the regulation of COUP-TFI activity remain unclear. The elucidation of several putative phosphorylation sites for MAPKs, PKC, and casein kinase II within the sequence of this orphan receptor led us to investigate phosphorylation events regulating the various COUP-TFI functions. After showing that COUP-TFI is phosphorylated in vivo, we provide evidence that in vivo inhibition of either MAPK or PKC signaling pathway leads to a specific and pronounced decrease in COUP-TFI-dependent transcriptional activation of the vitronectin gene promoter. Focusing on the molecular mechanisms underlying the MAPK- and PKC-mediated regulation of COUP-TFI activity, we show that COUP-TFI can be directly targeted by PKC and MAPK. These phosphorylation events differentially modulate COUP-TFI functions: PKC-mediated phosphorylation enhances COUP-TFI affinity for DNA and MAPK-mediated phosphorylation positively regulates the transactivation function of COUP-TFI, possibly through enhancing specific coactivator recruitment. These data provide evidence that COUP-TFI is likely to integrate distinct signaling pathways and raise the possibility that multiple extracellular signals influence biological processes controlled by COUP-TFI.

  5. Growth response of four freshwater algal species to dissolved organic nitrogen of different concentration and complexity

    DEFF Research Database (Denmark)

    Fiedler, Dorothea; Graeber, Daniel; Badrian, Maria

    2015-01-01

    1. Dissolved organic nitrogen (DON) compounds dominate the nitrogen pool of many lakes, but their importance as nitrogen sources for freshwater phytoplankton is not fully understood. Previous growth experiments demonstrated the availability of urea and amino acids but often at unnaturally high...... cases matched by nitrate. 4. Urea was also utilised over a longer time period than any other compound, including nitrate. The assumed delay in availability with increasing compound complexity was not supported by this experiment. 5. The studied species differed in their temporal response...... and their compound preferences. Therefore, DON composition can influence biomass and structure of phytoplankton communities. 6. These experiments demonstrate the importance of the main DON compounds for phytoplankton growth when no inorganic nitrogen is available. DON should in future be included in nitrogen budget...

  6. Membrane-localized ubiquitin ligase ATL15 functions in sugar-responsive growth regulation in Arabidopsis.

    Science.gov (United States)

    Aoyama, Shoki; Terada, Saki; Sanagi, Miho; Hasegawa, Yoko; Lu, Yu; Morita, Yoshie; Chiba, Yukako; Sato, Takeo; Yamaguchi, Junji

    2017-09-09

    Ubiquitin ligases play important roles in regulating various cellular processes by modulating the protein function of specific ubiquitination targets. The Arabidopsis Tóxicos en Levadura (ATL) family is a group of plant-specific RING-type ubiquitin ligases that localize to membranes via their N-terminal transmembrane-like domains. To date, 91 ATL isoforms have been identified in the Arabidopsis genome, with several ATLs reported to be involved in regulating plant responses to environmental stresses. However, the functions of most ATLs remain unknown. This study, involving transcriptome database analysis, identifies ATL15 as a sugar responsive ATL gene in Arabidopsis. ATL15 expression was rapidly down-regulated in the presence of sugar. The ATL15 protein showed ubiquitin ligase activity in vitro and localized to plasma membrane and endomembrane compartments. Further genetic analyses demonstrated that the atl15 knockout mutants are insensitive to high glucose concentrations, whereas ATL15 overexpression depresses plant growth. In addition, endogenous glucose and starch amounts were reciprocally affected in the atl15 knockout mutants and the ATL15 overexpressors. These results suggest that ATL15 protein plays a significant role as a membrane-localized ubiquitin ligase that regulates sugar-responsive plant growth in Arabidopsis. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. Modulations of the chicken cecal microbiome and metagenome in response to anticoccidial and growth promoter treatment.

    Directory of Open Access Journals (Sweden)

    Jessica L Danzeisen

    Full Text Available With increasing pressures to reduce or eliminate the use of antimicrobials for growth promotion purposes in production animals, there is a growing need to better understand the effects elicited by these agents in order to identify alternative approaches that might be used to maintain animal health. Antibiotic usage at subtherapeutic levels is postulated to confer a number of modulations in the microbes within the gut that ultimately result in growth promotion and reduced occurrence of disease. This study examined the effects of the coccidiostat monensin and the growth promoters virginiamycin and tylosin on the broiler chicken cecal microbiome and metagenome. Using a longitudinal design, cecal contents of commercial chickens were extracted and examined using 16S rRNA and total DNA shotgun metagenomic pyrosequencing. A number of genus-level enrichments and depletions were observed in response to monensin alone, or monensin in combination with virginiamycin or tylosin. Of note, monensin effects included depletions of Roseburia, Lactobacillus and Enterococcus, and enrichments in Coprococcus and Anaerofilum. The most notable effect observed in the monensin/virginiamycin and monensin/tylosin treatments, but not in the monensin-alone treatments, was enrichments in Escherichia coli. Analysis of the metagenomic dataset identified enrichments in transport system genes, type I fimbrial genes, and type IV conjugative secretion system genes. No significant differences were observed with regard to antimicrobial resistance gene counts. Overall, this study provides a more comprehensive glimpse of the chicken cecum microbial community, the modulations of this community in response to growth promoters, and targets for future efforts to mimic these effects using alternative approaches.

  8. Modulations of the chicken cecal microbiome and metagenome in response to anticoccidial and growth promoter treatment.

    Science.gov (United States)

    Danzeisen, Jessica L; Kim, Hyeun Bum; Isaacson, Richard E; Tu, Zheng Jin; Johnson, Timothy J

    2011-01-01

    With increasing pressures to reduce or eliminate the use of antimicrobials for growth promotion purposes in production animals, there is a growing need to better understand the effects elicited by these agents in order to identify alternative approaches that might be used to maintain animal health. Antibiotic usage at subtherapeutic levels is postulated to confer a number of modulations in the microbes within the gut that ultimately result in growth promotion and reduced occurrence of disease. This study examined the effects of the coccidiostat monensin and the growth promoters virginiamycin and tylosin on the broiler chicken cecal microbiome and metagenome. Using a longitudinal design, cecal contents of commercial chickens were extracted and examined using 16S rRNA and total DNA shotgun metagenomic pyrosequencing. A number of genus-level enrichments and depletions were observed in response to monensin alone, or monensin in combination with virginiamycin or tylosin. Of note, monensin effects included depletions of Roseburia, Lactobacillus and Enterococcus, and enrichments in Coprococcus and Anaerofilum. The most notable effect observed in the monensin/virginiamycin and monensin/tylosin treatments, but not in the monensin-alone treatments, was enrichments in Escherichia coli. Analysis of the metagenomic dataset identified enrichments in transport system genes, type I fimbrial genes, and type IV conjugative secretion system genes. No significant differences were observed with regard to antimicrobial resistance gene counts. Overall, this study provides a more comprehensive glimpse of the chicken cecum microbial community, the modulations of this community in response to growth promoters, and targets for future efforts to mimic these effects using alternative approaches.

  9. In Pichia pastoris, growth rate regulates protein synthesis and secretion, mating and stress response.

    Science.gov (United States)

    Rebnegger, Corinna; Graf, Alexandra B; Valli, Minoska; Steiger, Matthias G; Gasser, Brigitte; Maurer, Michael; Mattanovich, Diethard

    2014-04-01

    Protein production in yeasts is related to the specific growth rate μ. To elucidate on this correlation, we studied the transcriptome of Pichia pastoris at different specific growth rates by cultivating a strain secreting human serum albumin at μ = 0.015 to 0.15 h(-1) in glucose-limited chemostats. Genome-wide regulation revealed that translation-related as well as mitochondrial genes were upregulated with increasing μ, while autophagy and other proteolytic processes, carbon source-responsive genes and other targets of the TOR pathway as well as many transcriptional regulators were downregulated at higher μ. Mating and sporulation genes were most active at intermediate μ of 0.05 and 0.075 h(-1) . At very slow growth (μ = 0.015 h(-1) ) gene regulation differs significantly, affecting many transporters and glucose sensing. Analysis of a subset of genes related to protein folding and secretion reveals that unfolded protein response targets such as translocation, endoplasmic reticulum genes, and cytosolic chaperones are upregulated with increasing growth rate while proteolytic degradation of secretory proteins is downregulated. We conclude that a high μ positively affects specific protein secretion rates by acting on multiple cellular processes. © 2014 The Authors. Biotechnology Journal published by Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim. This is an open access article under the terms of the Creative Commons Attribution-Non-Commercial-NoDerivs Licence, which permits use and distribution in any medium, provided the original work is properly cited, the use is non- commercial and no modifications or adaptations are made.

  10. Anthropogenic nitrogen deposition alters growth responses of European beech (Fagus sylvativa L.) to climate change.

    Science.gov (United States)

    Hess, Carsten; Niemeyer, Thomas; Fichtner, Andreas; Jansen, Kirstin; Kunz, Matthias; Maneke, Moritz; von Wehrden, Henrik; Quante, Markus; Walmsley, David; von Oheimb, Goddert; Härdtle, Werner

    2018-02-01

    Global change affects the functioning of forest ecosystems and the services they provide, but little is known about the interactive effects of co-occurring global change drivers on important functions such as tree growth and vitality. In the present study we quantified the interactive (i.e. synergistic or antagonistic) effects of atmospheric nitrogen (N) deposition and climatic variables (temperature, precipitation) on tree growth (in terms of tree-ring width, TRW), taking forest ecosystems with European beech (Fagus sylvatica L.) as an example. We hypothesised that (i) N deposition and climatic variables can evoke non-additive responses of the radial increment of beech trees, and (ii) N loads have the potential to strengthen the trees' sensitivity to climate change. In young stands, we found a synergistic positive effect of N deposition and annual mean temperature on TRW, possibly linked to the alleviation of an N shortage in young stands. In mature stands, however, high N deposition significantly increased the trees' sensitivity to increasing annual mean temperatures (antagonistic effect on TRW), possibly due to increased fine root dieback, decreasing mycorrhizal colonization or shifts in biomass allocation patterns (aboveground vs. belowground). Accordingly, N deposition and climatic variables caused both synergistic and antagonistic effects on the radial increment of beech trees, depending on tree age and stand characteristics. Hence, the nature of interactions could mediate the long-term effects of global change drivers (including N deposition) on forest carbon sequestration. In conclusion, our findings illustrate that interaction processes between climatic variables and N deposition are complex and have the potential to impair growth and performance of European beech. This in turn emphasises the importance of multiple-factor studies to foster an integrated understanding and models aiming at improved projections of tree growth responses to co-occurring drivers

  11. 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. © 2013.

  12. Severe short stature and Wolf-Hirschhorn syndrome: response to growth hormone in two cases without growth hormone deficiency.

    Science.gov (United States)

    Austin, Devon E; Gunn, Alistair J; Jefferies, Craig A

    2015-02-01

    Wolf-Hirschhorn syndrome (WHS) is a rare congenital disorder occurring in approximately 1/50 000 births, with marked pre- and postnatal growth failure. WHS results from the hemizygous deletion encompassing the 4p16.3 region. This report of two children with WHS shows that growth hormone treatment in selected children with WHS and severe short stature may have a substantial effect on long-term growth.

  13. Transpiration Response and Growth in Pearl Millet Parental Lines and Hybrids Bred for Contrasting Rainfall Environments

    Directory of Open Access Journals (Sweden)

    Susan Medina

    2017-10-01

    Full Text Available Under conditions of high vapor pressure deficit (VPD and soil drying, restricting transpiration is an important avenue to gain efficiency in water use. The question we raise in this article is whether breeding for agro-ecological environments that differ for the rainfall have selected for traits that control plant water use. These are measured in pearl millet materials bred for zones varying in rainfall (8 combinations of parent and F1-hybrids, 18 F1-hybrids and then 40 F1-hybrids. In all cases, we found an agro-ecological variation in the slope of the transpiration response to increasing VPD, and parental line variation in the transpiration response to soil drying within hybrids/parent combinations. The hybrids adapted to lower rainfall had higher transpiration response curves than those from the highest rainfall zones, but showed no variation in how transpiration responded to soil drying. The genotypes bred for lower rainfall zones showed lower leaf area, dry matter, thicker leaves, root development, and exudation, than the ones bred for high rainfall zone when grown in the low VPD environment of the greenhouse, but there was no difference in their root length neither on the root/shoot index in these genotypes. By contrast, when grown under high VPD conditions outdoors, the lower rainfall hybrids had the highest leaf, tiller, and biomass development. Finally, under soil drying the genotypes from the lower rainfall accumulated less biomass than the ones from higher rainfall zone, and so did the parental lines compared to the hybrids. These differences in the transpiration response and growth clearly showed that breeding for different agro-ecological zones also bred for different genotype strategies in relation to traits related to plant water use.Highlights:• Variation in transpiration response reflected breeding for agro-ecological zones• Different growth strategies depended on the environmental conditions• Different ideotypes reflected

  14. Dietary supplementation of probiotics affects growth, immune response and disease resistance of Cyprinus carpio fry.

    Science.gov (United States)

    Gupta, Akhil; Gupta, Paromita; Dhawan, Asha

    2014-12-01

    The effects of dietary Bacillus coagulans (MTCC 9872), Bacillus licheniformis (MTCC 6824) and Paenibacillus polymyxa (MTCC 122) supplementation on growth performance, non-specific immunity and protection against Aeromonas hydrophila infection were evaluated in common carp, Cyprinus carpio fry. Laboratory maintained B. coagulans, B. licheniformis and P. polymyxa were used to study antagonistic activity against fish pathogenic bacteria by agar well diffusion assay. Healthy fish fry were challenged by this bacterium for determination of its safety. Fish were fed for 80 days with control basal diet (B0) and experimental diets containing B. coagulans (B1), B. licheniformis (B2) and P. polymyxa (B3) at 10(9) CFU/g diet. Fish fry (mean weight 0.329 ± 0.01 g) were fed these diets and growth performance, various non-specific immune parameters and disease resistance study were conducted at 80 days post-feeding. The antagonism study showed inhibition zone against A. hydrophila and Vibrio harveyi. All the probiotic bacterial strains were harmless to fish fry as neither mortality nor morbidities were observed of the challenge. The growth-promoting influences of probiotic supplemented dietary treatments were observed with fish fry and the optimum survival, growth and feed utilization were obtained with P. polymyxa (B3) supplemented diet. Study of different non-specific innate immunological parameters viz. lysozyme activity, respiratory burst assay and myeloperoxidase content showed significant (p fry fed B3 diet at 10(9) CFU/g. The challenge test showed dietary supplementation of B. coagulans, B. licheniformis and P. polymyxa significantly (p fry against bacterial challenge. These results collectively suggests that P. polymyxa is a potential probiotic species and can be used in aquaculture to improve growth, feed utilization, non-specific immune responses and disease resistance of fry common carp, C. carpio. Copyright © 2014. Published by Elsevier Ltd.

  15. Dopamine-Responsive Growth-Hormone Deficiency and Central Hypothyroidism in Sepiapterin Reductase Deficiency.

    Science.gov (United States)

    Zielonka, Matthias; Makhseed, Nawal; Blau, Nenad; Bettendorf, Markus; Hoffmann, Georg Friedrich; Opladen, Thomas

    2015-01-01

    Sepiapterin reductase (SR) deficiency is a rare autosomal recessively inherited error of tetrahydrobiopterin (BH4) biosynthesis, resulting in disturbed dopaminergic and serotonergic neurotransmission. The clinical phenotype is characterized by dopa-responsive movement disorders including muscular hypotonia, dystonia, and parkinsonism. Due to the rarity of the disease, the phenotype of SR deficiency is far from being completely understood. Here, we report a 7-year-old boy, who was referred for diagnostic evaluation of combined psychomotor retardation, spastic tetraplegia, extrapyramidal symptoms, and short stature. Due to discrepancy between motor status and mental condition, analyses of biogenic amines and pterins in CSF were performed, leading to the diagnosis of SR deficiency. The diagnosis was confirmed by a novel homozygous mutation c.530G>C; p.(Arg177Pro) in exon 2 of the SPR gene. Because of persistent short stature, systematic endocrinological investigations were initiated. Insufficient growth-hormone release in a severe hypoglycemic episode after overnight fasting confirmed growth-hormone deficiency as a cause of short stature. In addition, central hypothyroidism was present. A general hypothalamic affection could be excluded. Since dopamine is known to regulate growth-hormone excretion, IGF-1, IGF-BP3, and peripheral thyroid hormone levels were monitored under L-dopa/carbidopa supplementation. Both growth-hormone-dependent factors and thyroid function normalized under treatment. This is the first report describing growth-hormone deficiency and central hypothyroidism in SR deficiency. It extends the phenotypic spectrum of the disease and identifies dopamine depletion as cause for the endocrinological disturbances.

  16. [Growth response of Abies fargesii to climate in Shennongjia Mount of Hubei Province, Southeastern China].

    Science.gov (United States)

    Hou, Xin-yuan; Shi, Jiang-feng; Li, Ling-ling; Lu, Hua-yu

    2015-03-01

    A well-replicated Abies fargesii tree-ring width chronology in the Shennongjia Mount was developed to investigate its radial growth response to climate variables (e.g., monthly mean tempe- rature and total precipitation) and other growing season indicators (e.g., cumulative temperature, continuous days, initial and final dates). Correlation analyses showed that the tree-ring width was positively correlated to the mean temperatures of February, April and September, and negatively correlated to the total precipitation of September, prior September and prior December. The analyses between the chronology and other growing season parameters showed that tree growth responded positively to the cumulative temperature and continuous days of the growing season. The correlation was the highest when the growing season was defined as the days above the temperature threshold of 9.0 °C. Defined this way, the growing season typically started in late-May and ended in mid-September, lasting about 120 days. Correlation analyses were also conducted between the tree-ring growth and the initial and final dates of the growing season. Results showed that correlation was the highest for initial dates defined at 9.0 °C (with the coefficient of -0.25 and p-value close to 0.05), and for final dates defined at 9.3 °C (with the coefficient of 0.33 and p-value less than 0.05). All these results indicated that the sensitive temperature threshold for photosynthesis of A. fargesii was around 9.0 °C. The year 1978 marked an abrupt shift of climate in southeast China. We compared A. fargesii growth between pre-1978 and post-1978 periods. Results showed that as temperature rose, the growing season was lengthened with both earlier initial dates and later final dates. Longer growing season increased the A. fargesii growth in the Shennongjia Mount, southeastern China.

  17. Introduction of exogenous growth hormone receptors augments growth hormone-responsive insulin biosynthesis in rat insulinoma cells

    International Nuclear Information System (INIS)

    Billestrup, N.; Moeldrup, A.; Serup, P.; Nielsen, J.H.; Mathews, L.S.; Norstedt, G.

    1990-01-01

    The stimulation of insulin biosynthesis in the pancreatic insulinoma cell line RIN5-AH by growth hormone (GH) is initiated by GH binding to specific receptors. To determine whether the recently cloned rat hepatic GH receptor is able to mediate the insulinotropic effect of GH, the authors have transfected a GH receptor cDNA under the transcriptional control of the human metallothionein promoter into RIN5-AH cells. The transfected cells were found to exhibit an increased expression of GH receptors and to contain a specific GH receptor mRNA that was not expressed in the parent cell line. The expression of GH receptors in one clone (1.24) selected for detailed analysis was increased 2.6-fold compared to untransfected cells. The increased GH receptor expression was accompanied by an increased responsiveness to GH. Thus, the maximal GH-stimulated increase of insulin biosynthesis was 4.1-fold in 1.24 cells compared to 1.9-fold in the nontransfected RIN5-AH cells. The expression of the transfected receptor was stimulated 1.6- and 2.3-fold when cells were cultured in the presence of 25 or 50 μM Zn 2+ was associated with an increased magnitude of GH-stimulated insulin biosynthesis. A close stoichiometric relationship between the level of receptor expression and the level of GH-stimulated insulin biosynthesis was observed. They conclude from these results that the hepatic GH receptor is able to mediate the effect of GH on insulin biosynthesis in RIN5-AH cells

  18. Optimization of Growth Medium for Efficient Cultivation of Lactobacillus salivarius i 24 using Response Surface Method

    Directory of Open Access Journals (Sweden)

    Lim, C. H.

    2007-01-01

    Full Text Available Production of Lactobacillus salivarius i 24, a probiotic strain for chicken, was studied in batch fermentation using 500 mL Erlenmeyer flask. Response surface method (RSM was used to optimize the medium for efficient cultivation of the bacterium. The factors investigated were yeast extract, glucose and initial culture pH. A polynomial regression model with cubic and quartic terms was used for the analysis of the experimental data. Estimated optimal conditions of the factors for growth of L. salivarius i 24 were; 3.32 % (w/v glucose, 4.31 % (w/v yeast extract and initial culture pH of 6.10.

  19. ALTERATIONS TO PLBS AND PLANTLETS OF HYBRID CYMBIDIUM (ORCHIDACEAE IN RESPONSE TO PLANT GROWTH REGULATORS

    Directory of Open Access Journals (Sweden)

    Jaime A. TEIXEIRA DA SILVA

    2015-12-01

    Full Text Available A previous study examined, in detail, the morphological response of hybrid Cymbidium Twilight Moon ‘Day Light’ protocorm-like bodies (PLBs to 26 plant growth regulators (PGRs. In this study, flow cytometric analyses of the PLBs derived from several of these PGR treatments revealed changes in the ploidy of PLBs while the ploidy of plant leaves remained constant. The SPAD value of leaves of plants derived from PGR treatments changed significantly. The choice of PGR must be accompanied by careful scrutiny of the possible resulting changes to morphology and physiological parameters.

  20. Arabidopsis ZED1-related kinases mediate the temperature-sensitive intersection of immune response and growth homeostasis.

    Science.gov (United States)

    Wang, Zhicai; Cui, Dayong; Liu, Jing; Zhao, Jingbo; Liu, Cheng; Xin, Wei; Li, Yuan; Liu, Na; Ren, Dongtao; Tang, Dingzhong; Hu, Yuxin

    2017-07-01

    Activation of the immune response in plants antagonizes growth and development in the absence of pathogens, and such an autoimmune phenotype is often suppressed by the elevation of ambient temperature. However, molecular regulation of the ambient temperature-sensitive intersection of immune response and growth is largely elusive. A genetic screen identified an Arabidopsis mutant, zed1-D, by its high temperature-dependent growth retardation. A combination of molecular, cytological and genetic approaches was used to investigate the molecular basis behind the temperature-sensitive growth and immune response in zed1-D. A dominant mutation in HOPZ-ETI-DEFICIENT 1 (ZED1) is responsible for a high temperature-dependent autoimmunity and growth retardation in zed1-D. The autoimmune phenotype in zed1-D is dependent on the HOPZ-ACTIVATED RESISTANCE 1 (ZAR1). ZED1 and some ZED1-related kinases (ZRKs) are induced by elevated temperature and function cooperatively to suppress the immune response by modulating the transcription of SUPPRESSOR OF NPR1-1 CONSTITUTIVE 1 (SNC1) in the absence of pathogens. Our data reveal a previously unidentified role of ZRKs in the ambient temperature-sensitive immune response in the absence of pathogens, and thus reveals a possible molecular mechanism underlying the temperature-mediated intersection of immune response and growth in plants. © 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.