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Sample records for growth hormone-releasing peptide-6

  1. Growth Hormone-Releasing Peptide 6 Enhances the Healing Process and Improves the Esthetic Outcome of the Wounds

    Yssel Mendoza Marí

    2016-01-01

    Full Text Available In addition to its cytoprotective effects, growth hormone-releasing peptide 6 (GHRP-6 proved to reduce liver fibrotic induration. CD36 as one of the GHRP-6 receptors appears abundantly represented in cutaneous wounds granulation tissue. The healing response in a scenario of CD36 agonistic stimulation had not been previously investigated. Excisional full-thickness wounds (6 mmØ were created in the dorsum of Wistar rats and topically treated twice a day for 5 days. The universal model of rabbit’s ears hypertrophic scars was implemented and the animals were treated daily for 30 days. Treatments for both species were based on a CMC jelly composition containing GHRP-6 400 μg/mL. Wounds response characterization included closure dynamic, RT-PCR transcriptional profile, histology, and histomorphometric procedures. The rats experiment indicated that GHRP-6 pharmacodynamics involves attenuation of immunoinflammatory mediators, their effector cells, and the reduction of the expression of fibrotic cytokines. Importantly, in the hypertrophic scars rabbit’s model, GHRP-6 intervention dramatically reduced the onset of exuberant scars by activating PPARγ and reducing the expression of fibrogenic cytokines. GHRP-6 showed no effect on the reversion of consolidated lesions. This evidence supports the notion that CD36 is an active and pharmacologically approachable receptor to attenuate wound inflammation and accelerate its closure so as to improve wound esthetic.

  2. Growth hormone-releasing peptides.

    Ghigo, E; Arvat, E; Muccioli, G; Camanni, F

    1997-05-01

    Growth hormone-releasing peptides (GHRPs) are synthetic, non-natural peptides endowed with potent stimulatory effects on somatotrope secretion in animals and humans. They have no structural homology with GHRH and act via specific receptors present either at the pituitary or the hypothalamic level both in animals and in humans. The GHRP receptor has recently been cloned and, interestingly, it does not show sequence homology with other G-protein-coupled receptors known so far. This evidence strongly suggests the existence of a natural GHRP-like ligand which, however, has not yet been found. The mechanisms underlying the GHRP effect are still unclear. At present, several data favor the hypothesis that GHRPs could act by counteracting somatostatinergic activity both at the pituitary and the hypothalamic level and/or, at least partially, via a GHRH-mediated mechanism. However, the possibility that GHRPs act via an unknown hypothalamic factor (U factor) is still open. GHRP-6 was the first hexapeptide to be extensively studied in humans. More recently, a heptapeptide, GHRP-1, and two other hexapeptides, GHRP-2 and Hexarelin, have been synthesized and are now available for human studies. Moreover, non-peptidyl GHRP mimetics have been developed which act via GHRP receptors and their effects have been clearly demonstrated in animals and in humans in vivo. Among non-peptidyl GHRPs, MK-0677 seems the most interesting molecule. The GH-releasing activity of GHRPs is marked and dose-related after intravenous, subcutaneous, intranasal and even oral administration. The effect of GHRPs is reproducible and undergoes partial desensitization, more during continuous infusion, less during intermittent administration: in fact, prolonged administration of GHRPs increases IGF-1 levels both in animals and in humans. The GH-releasing effect of GHRPs does not depend on sex but undergoes age-related variations. It increases from birth to puberty, persists at a similar level in adulthood and

  3. Growth Hormone-Releasing Hormone in Diabetes

    Leonid Evsey Fridlyand

    2016-10-01

    Full Text Available Growth hormone-releasing hormone (GHRH is produced by the hypothalamus and stimulates growth hormone synthesis and release in the anterior pituitary gland. In addition GHRH is an important regulator of cellular functions in many cells and organs. Expression of GHRH G-Protein Coupled Receptor (GHRHR has been demonstrated in different peripheral tissues and cell types including pancreatic islets. Among the peripheral activities, recent studies demonstrate a novel ability of GHRH analogs to increase and preserve insulin secretion by beta-cells in isolated pancreatic islets, which makes them potentially useful for diabetes treatment. This review considers the role of GHRHR in the beta-cell and addresses the unique engineered GHRH agonists and antagonists for treatment of Type 2 diabetes mellitus. We discuss the similarity of signaling pathways activated by GHRHR in pituitary somatotrophs and in pancreatic beta-cells and possible ways as to how the GHRHR pathway can interact with glucose and other secretagogues to stimulate insulin secretion. We also consider the hypothesis that novel GHRHR agonists can improve glucose metabolism in Type 2 diabetes by preserving the function and survival of pancreatic beta-cells. Wound healing and cardioprotective action with new GHRH agonists suggesting that they may prove useful in ameliorating certain diabetic complications. These findings highlight the future potential therapeutic effectiveness of modulators of GHRHR activity for the development of new therapeutic approaches in diabetes and its complications.

  4. Effect of growth hormone-releasing factor on growth hormone release in children with radiation-induced growth hormone deficiency

    Lustig, R.H.; Schriock, E.A.; Kaplan, S.L.; Grumbach, M.M.

    1985-01-01

    Five male children who received cranial irradiation for extrahypothalamic intracranial neoplasms or leukemia and subsequently developed severe growth hormone (GH) deficiency were challenged with synthetic growth hormone-releasing factor (GRF-44), in an attempt to distinguish hypothalamic from pituitary dysfunction as a cause of their GH deficiency, and to assess the readily releasable GH reserve in the pituitary. In response to a pulse of GRF-44 (5 micrograms/kg intravenously), mean peak GH levels rose to values higher than those evoked by the pharmacologic agents L-dopa or arginine (6.4 +/- 1.3 ng/mL v 1.5 +/- 0.4 ng/mL, P less than .05). The peak GH value occurred at a mean of 26.0 minutes after administration of GRF-44. These responses were similar to those obtained in children with severe GH deficiency due to other etiologies (peak GH 6.3 +/- 1.7 ng/mL, mean 28.0 minutes). In addition, there was a trend toward an inverse relationship between peak GH response to GRF-44 and the postirradiation interval. Prolactin and somatomedin-C levels did not change significantly after the administration of a single dose of GRF-44. The results of this study support the hypothesis that cranial irradiation in children can lead to hypothalamic GRF deficiency secondary to radiation injury of hypothalamic GRF-secreting neurons. This study also lends support to the potential therapeutic usefulness of GRF-44 or an analog for GH deficiency secondary to cranial irradiation

  5. Algorithmic complexity of growth hormone release in humans

    Prank, K.; Wagner, M.; Brabant, G. [Medical School Hannover (Germany)

    1996-12-31

    Most hormones are secreted in an pulsatile rather than in a constant manner. This temporal pattern of pulsatile hormone release plays an important role in the regulation of cellular function and structure. In healthy humans growth hormone (GH) secretion is characterized by distinct pulses whereas patients bearing a GH producing tumor accompanied with excessive secretion (acromegaly) exhibit a highly irregular pattern of GH release. It has been hypothesized that this highly disorderly pattern of GH release in acromegaly arises from random events in the GH-producing tumor under decreased normal control of GH secretion. Using a context-free grammar complexity measure (algorithmic complexity) in conjunction with random surrogate data sets we demonstrate that the temporal pattern of GH release in acromegaly is not significantly different from a variety of stochastic processes. In contrast, normal subjects clearly exhibit deterministic structure in their temporal patterns of GH secretion. Our results support the hypothesis that GH release in acromegaly is due to random events in the GH-producing tumorous cells which might become independent from hypothalamic regulation. 17 refs., 1 fig., 2 tabs.

  6. Potent agonists of growth hormone-releasing hormone. Part I.

    Zarandi, M; Serfozo, P; Zsigo, J; Bokser, L; Janaky, T; Olsen, D B; Bajusz, S; Schally, A V

    1992-03-01

    Analogs of the 29 amino acid sequence of growth hormone-releasing hormone (GH-RH) with agmatine (Agm) in position 29 have been synthesized by the solid phase method, purified, and tested in vitro and in vivo. The majority of the analogs contained desaminotyrosine (Dat) in position 1, but a few of them had Tyr1, or N-MeTyr1. Some peptides contained one or more additional L- or D-amino acid substitutions in positions 2, 12, 15, 21, 27, and/or 28. Compared to the natural sequence of GH-RH(1-29)NH2, [Dat1,Ala15]GH-RH(1-28)Agm (MZ-3-191) and [D-Ala2,Ala15]GH-RH(1-28)Agm (MZ-3-201) were 8.2 and 7.1 times more potent in vitro, respectively. These two peptides contained Met27. Their Nle27 analogs, [Dat1,Ala15,Nle27]GH-RH(1-28)Agm(MZ-2-51), prepared previously (9), and [D-Ala2,Ala15,Nle28]GH-RH(1-28)Agm(MZ-3-195) showed relative in vitro potencies of 10.5 and 2.4, respectively. These data indicate that replacement of Met27 by Nle27 enhanced the GH-releasing activity of the analog when the molecule contained Dat1-Ala2 residues at the N-terminus, but peptides containing Tyr1-D-Ala2 in addition to Nle27 showed decreased potencies. Replacement of Ser28 with Asp in multi-substituted analogs of GH-RH(1-28)Agm resulted in a decrease in in vitro potencies compared to the parent compound. Thus, the Ser28-containing MZ-2-51, and [Dat1,Ala15,D-Lys21,Nle27]GH-RH(1-28)Agm, its Asp28 homolog (MZ-3-149), possessed relative activities of 10.5 and 5.6, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

  7. Preliminary studies of plasma growth hormone releasing activity during medical therapy of acromegaly

    Hagen, T.C.; Lawrence, A.M.; Kirsteins, L.

    1978-01-01

    The in vitro growth hormone releasing activity of plasma obtained from six acromegalic subjects was measured before and during therapy. In five subjects, plasmas were obtained before and during successful medical therapy with medroxyprogesterone acetate (MPA). The sixth subject was sampled before and after transphenoidal Sr 90 -induced hypopituitarism. All subjects had a decrement in fasting growth hormone levels with respective therapies (29-88%). The in vitro growth hormone released from Rhesus monkey anterior pituitaries was assessed after incubating one lateral half in control plasma (pre-therapy) and the contralateral pituitary half in plasma obtained during or after therapy. Studies with plasmas obtained from the five patients successfully treated with MPA showed a decrease in growth hormone releasing activity during therapy in all (18-57%). Plasma obtained after Sr 90 pituitary ablation in the sixth subject had 35% more growth hormone releasing activity than obtained before therapy. These results suggest that active acromegalics who respond to MPA with significantly lowered growth hormone levels may actually achieve this response because of a decrease in growth hormone releasing factor measured peripherally. The opposite response in one acromegalic subject, following Sr 90 pituitary ablation and hypopituitarism, suggests that growth hormone releasing factor secretion may increase when growth hormone levels are lowered by ablative therapy. (orig.) [de

  8. Growth hormone-releasing factor stimulates proliferation of somatotrophs in vitro

    Billestrup, Nils; Swanson, L W; Vale, W

    1986-01-01

    The mitogenic effect of the hypothalamic peptides growth hormone-releasing factor (GRF) and somatostatin on cultured growth hormone (GH)-producing cells (somatotrophs) was studied. Using autoradiographic detection of [3H]thymidine uptake and immunocytochemical identification of GH-producing cells...

  9. Pituitary mammosomatotroph adenomas develop in old mice transgenic for growth hormone-releasing hormone

    Asa, S L; Kovacs, K; Stefaneanu, L

    1990-01-01

    It has been shown that mice transgenic for human growth hormone-releasing hormone (GRH) develop hyperplasia of pituitary somatotrophs and mammosomatotrophs, cells capable of producing both growth hormone and prolactin, by 8 months of age. We now report for the first time that old GRH-transgenic...

  10. Endurance exercise modulates levodopa induced growth hormone release in patients with Parkinson's disease.

    Müller, Thomas; Welnic, Jacub; Woitalla, Dirk; Muhlack, Siegfried

    2007-07-11

    Acute levodopa (LD) application and exercise release human growth hormone (GH). An earlier trial showed, that combined stimulus of exercise and LD administration is the best provocative test for GH response in healthy participants. Objective was to show this combined effect of LD application and exercise on GH response and to investigate the impact on LD metabolism in 20 previously treated patients with Parkinson's disease (PD). We measured GH- and LD plasma concentrations following soluble 200 mg LD/50 mg benserazide administration during endurance exercise and rest on two separate consecutive days. GH concentrations significantly increased on both days, but GH release was significantly delayed during rest. LD metabolism was not altered due to exercise in a clinical relevant manner. Exercise induced a significant faster LD stimulated GH release in comparison with the rest condition. We did not find the supposed increase of LD induced GH release by endurance exercise. We assume, that only a limited amount of GH is available for GH release in the anterior pituitary following an acute 200 mg LD administration. GH disposal also depends on growth hormone releasing hormone (GHRH), which is secreted into hypothalamic portal capillaries. During the exercise condition, the resulting higher blood pressure supports blood flow and thus GHRH transport towards the GH producing cells in the pituitary. This might additionally have caused the significant faster GH release during exercise.

  11. Levels of human and rat hypothalamic growth hormone-releasing factor as determined by specific radioimmunoassay systems

    Audhya, T.; Manzione, M.M.; Nakane, T.; Kanie, N.; Passarelli, J.; Russo, M.; Hollander, C.S.

    1985-01-01

    Polyclonal antibodies to synthetic human pancreatic growth hormone-releasing factor [hpGRF(1-44)NH 2 ] and rat hypothalamic growth hormone-releasing factor [rhGRF(1-43)OH] were produced in rabbits. A subsequent booster injection by the conventional intramuscular route resulted in high-titer antibodies, which at a 1:20,000 dilution were used to develop highly sensitive and specific radioimmunoassays for these peptides. The antibody to hpGRF(1-44)NH 2 is directed against the COOH-terminal region of the molecule, as shown by its cross reactivity with various hpGRF analogues. Serial dilutions of human and rat hypothalamic extracts demonstrated parallelism with the corresponding species-specific standard and 125 I-labeled tracer. There was no cross reactivity with other neuropeptides, gastrointestinal peptides, or hypothalamic extracts of other species. Age-related changes in hypothalamic GRF content were present in rats, with a gradual increase from 2 to 16 weeks and a correlation between increasing body weight and GRF content. These radioimmunoassays will serve as important tools for understanding the regulation of growth hormone secretion in both human and rat

  12. A role for central nervous growth hormone-releasing hormone signaling in the consolidation of declarative memories.

    Manfred Hallschmid

    Full Text Available Contributions of somatotropic hormonal activity to memory functions in humans, which are suggested by clinical observations, have not been systematically examined. With previous experiments precluding a direct effect of systemic growth hormone (GH on acute memory formation, we assessed the role of central nervous somatotropic signaling in declarative memory consolidation. We examined the effect of intranasally administered growth hormone releasing-hormone (GHRH; 600 µg that has direct access to the brain and suppresses endogenous GHRH via an ultra-short negative feedback loop. Twelve healthy young men learned word-pair associates at 2030 h and were administered GHRH and placebo, respectively, at 2100 h. Retrieval was tested after 11 hours of wakefulness. Compared to placebo, intranasal GHRH blunted GH release within 3 hours after substance administration and reduced the number of correctly recalled word-pairs by ∼12% (both P<0.05. The impairment of declarative memory consolidation was directly correlated to diminished GH concentrations (P<0.05. Procedural memory consolidation as examined by the parallel assessment of finger sequence tapping performance was not affected by GHRH administration. Our findings indicate that intranasal GHRH, by counteracting endogenous GHRH release, impairs hippocampal memory processing. They provide first evidence for a critical contribution of central nervous somatotropic activity to hippocampus-dependent memory consolidation.

  13. Prolactin, thyrotropin, and growth hormone release during stress associated with parachute jumping.

    Noel, G L; Dimond, R C; Earll, J M; Frantz, A G

    1976-05-01

    Prolactin, growth hormone, and thyrotropin (TSH) release during the stress of parachute jumping has been evaluated in 14 male subjects. Subjects were studied at several times before and immediately after their first military parachute jump. All three hormones had risen significantly 1 to 14 min after the jump, compared to mean levels measured immediately beforehand. Earlier studies of physical exercise by ourselves and others would suggest that emotional stress played a role in producing changes of this magnitude. We conclude that prolactin, TSH, and growth hormone are released in physiologically significant amounts in association with the stress of parachute jumping.

  14. Diseases associated with growth hormone-releasing hormone receptor (GHRHR) mutations.

    Martari, Marco; Salvatori, Roberto

    2009-01-01

    The growth hormone (GH)-releasing hormone (GHRH) receptor (GHRHR) belongs to the G protein-coupled receptors family. It is expressed almost exclusively in the anterior pituitary, where it is necessary for somatotroph cells proliferation and for GH synthesis and secretion. Mutations in the human GHRHR gene (GHRHR) can impair ligand binding and signal transduction, and have been estimated to cause about 10% of autosomal recessive familial isolated growth hormone deficiency (IGHD). Mutations reported to date include five splice donor site mutations, two microdeletions, two nonsense mutations, seven missense mutations, and one mutation in the promoter. These mutations have an autosomal recessive mode of inheritance, and heterozygous individuals do not show signs of IGHD, although the presence of an intermediate phenotype has been hypothesized. Conversely, patients with biallelic mutations have low serum insulin-like growth factor-1 and GH levels (with absent or reduced GH response to exogenous stimuli), resulting--if not treated--in proportionate dwarfism. This chapter reviews the biology of the GHRHR, the mutations that affect its gene and their effects in homozygous and heterozygous individuals. Copyright © 2009 Elsevier Inc. All rights reserved.

  15. Structural and functional divergence of growth hormone-releasing hormone receptors in early sarcopterygians: lungfish and Xenopus.

    Janice K V Tam

    Full Text Available The evolutionary trajectories of growth hormone-releasing hormone (GHRH receptor remain enigmatic since the discovery of physiologically functional GHRH-GHRH receptor (GHRHR in non-mammalian vertebrates in 2007. Interestingly, subsequent studies have described the identification of a GHRHR(2 in chicken in addition to the GHRHR and the closely related paralogous receptor, PACAP-related peptide (PRP receptor (PRPR. In this article, we provide information, for the first time, on the GHRHR in sarcopterygian fish and amphibians by the cloning and characterization of GHRHRs from lungfish (P. dolloi and X. laevis. Sequence alignment and phylogenetic analyses demonstrated structural resemblance of lungfish GHRHR to their mammalian orthologs, while the X. laevis GHRHR showed the highest homology to GHRHR(2 in zebrafish and chicken. Functionally, lungfish GHRHR displayed high affinity towards GHRH in triggering intracellular cAMP and calcium accumulation, while X. laevis GHRHR(2 was able to react with both endogenous GHRH and PRP. Tissue distribution analyses showed that both lungfish GHRHR and X. laevis GHRHR(2 had the highest expression in brain, and interestingly, X. laevis(GHRHR2 also had high abundance in the reproductive organs. These findings, together with previous reports, suggest that early in the Sarcopterygii lineage, GHRHR and PRPR have already established diverged and specific affinities towards their cognate ligands. GHRHR(2, which has only been found in xenopus, zebrafish and chicken hitherto, accommodates both GHRH and PRP.

  16. Growth hormone releasing hormone (GHRH) signaling modulates intermittent hypoxia-induced oxidative stress and cognitive deficits in mouse.

    Nair, Deepti; Ramesh, Vijay; Li, Richard C; Schally, Andrew V; Gozal, David

    2013-11-01

    Intermittent hypoxia (IH) during sleep, such as occurs in obstructive sleep apnea (OSA), leads to degenerative changes in the hippocampus, and is associated with spatial learning deficits in adult mice. In both patients and murine models of OSA, the disease is associated with suppression of growth hormone (GH) secretion, which is actively involved in the growth, development, and function of the central nervous system (CNS). Recent work showed that exogenous GH therapy attenuated neurocognitive deficits elicited by IH during sleep in rats. Here, we show that administration of the Growth Hormone Releasing Hormone (GHRH) agonist JI-34 attenuates IH-induced neurocognitive deficits, anxiety, and depression in mice along with reduction in oxidative stress markers such as MDA and 8-hydroxydeoxyguanosine, and increases in hypoxia inducible factor-1α DNA binding and up-regulation of insulin growth factor-1 and erythropoietin expression. In contrast, treatment with a GHRH antagonist (MIA-602) during intermittent hypoxia did not affect any of the IH-induced deleterious effects in mice. Thus, exogenous GHRH administered as the formulation of a GHRH agonist may provide a viable therapeutic intervention to protect IH-vulnerable brain regions from OSA-associated neurocognitive dysfunction. Sleep apnea, characterized by chronic intermittent hypoxia (IH), is associated with substantial cognitive and behavioral deficits. Here, we show that administration of a GHRH agonist (JI-34) reduces oxidative stress, increases both HIF-1α nuclear binding and downstream expression of IGF1 and erythropoietin (EPO) in hippocampus and cortex, and markedly attenuates water maze performance deficits in mice exposed to intermittent hypoxia during sleep. © 2013 International Society for Neurochemistry.

  17. Effects of hyperthyroidism and hypothyroidism on rat growth hormone release induced by thyrotropin-releasing hormone.

    Chihara, K; Kato, Y; Ohgo, S; Iwasaki, Y; Maeda, K

    1976-06-01

    The effect of synthetic thyrotropin-releasing hormone (TRH) on the release of growth hormone (GH) and thyroid-stimulating hormone (TSH) was investigated in euthyroid, hypothyroid, and hyperthyroid rats under urethane anesthesia. In euthyroid control rats, intravenous injection of TRH (200 ng/100 g BW) resulted in a significant increase in both plasma GH and TSH. In rats made hypothyroid by treatment with propylthiouracil or by thyroidectomy, basal GH and TSH levels were significantly elevated with exaggerated responses to TRH. In contrast, plasma GH and TSH responses to TRH were both significantly inhibited in rats made hyperthyroid by L-thyroxine (T4) treatment. These results suggest that altered thyroid status influences GH release as well as TSH secretion induced by TRH in rats.

  18. Effects of an Antagonistic Analog of Growth Hormone-Releasing Hormone on Endometriosis in a Mouse Model and In Vitro.

    Köster, Frank; Jin, Li; Shen, Yuanming; Schally, Andrew V; Cai, Ren-Zhi; Block, Norman L; Hornung, Daniela; Marschner, Gabriele; Rody, Achim; Engel, Jörg B; Finas, Dominique

    2017-11-01

    Endometriosis is a benign gynecologic disorder causing dysmenorrhea, pelvic pain, and subfertility. Receptors for the growth hormone-releasing hormone (GHRH) were found in endometriotic tissues. Antagonists of GHRH have been used to inhibit the growth of endometriotic endometrial stromal cells. In this study, the GHRH receptor splice variant (SV) 1 was detected in human endometrial tissue samples by Western blots and quantitative reverse transcription polymerase chain reaction (qRT-PCR). The highest messenger RNA (mRNA) and protein levels of SV1 were found in eutopic endometrium from patients with endometriosis compared to ectopic endometriotic tissues and endometrium from normal patients. The highest expression for GHRH mRNA was found by qRT-PCR in ectopic endometriosis lesions. In an in vivo mouse model with human endometrial explants from patients with endometriosis, 10 μg MIA-602 per day resulted in significantly smaller human endometrial xenotransplants after 4 weeks compared to mice treated with vehicle. The endometrial tissues expressed SV1 before and after xenotransplantation. The proliferation of endometrial stromal cells as well as the endometriosis cell lines 12-Z and 49-Z was decreased by exposure to 1 μM MIA-602 after 72 hours. The protein levels of epithelial growth factor receptors in 12-Z and 49-Z cell lines were reduced 48 and 72 hours after the administration of 1 μM MIA-602. MIA-602 decreased the activation of the MAP-kinases ERK-1/2. Our study demonstrates the presence of SV1 receptor as a target for treatment with GHRH antagonist in endometriosis. Endometrial tissues respond to MIA-602 with inhibition of proliferation in vitro and in vivo. The use of MIA-602 could be an effective supplement to the treatment strategies in endometriosis.

  19. Role of the new growth hormone-releasing secretagogues in the diagnosis of some hypothalamopituitary pathologies.

    Casanueva, F F; Micic, D; Pombo, M; Leal, A; Bokser, L; Zugaza, J L; Dieguez, C

    1996-08-01

    Growth hormone (GH)-releasing hormone (GHRH) and somatostatin have a dominant role in regulating GH secretion. However, results of studies using the new class of GH secretogogues, particularly GHRP-6, indicate that there may also be other, as yet undefined, hypothalamic mechanisms involved. Studies in adults with hypothalamopituitary disconnection (functional pituitary stalk transection), show GHRP-6-mediated GH release to be completely blocked, indicating a main action at the hypothalamic rather than the pituitary level. The synergistic effect of GHRH plus GHRP-6 administration on GH release seen in normal adults (and virtually unaffected by age, obesity, or sex) is also absent in these patients, providing further support for this conclusion. Studies of the effects of GHRP-6 in children with GH deficiency due to perinatal pituitary stalk transection have produced similar findings. It is suggested that the combined GHRH plus GHRH-6 test should be a promising tool for diagnosing GH deficiency states in both children and adults, and may identify a subgroup of patients with GH deficiency caused by interruption of the hypothalamopituitary connection.

  20. Identification of CJC-1295, a growth-hormone-releasing peptide, in an unknown pharmaceutical preparation.

    Henninge, John; Pepaj, Milaim; Hullstein, Ingunn; Hemmersbach, Peter

    2010-01-01

    Several peptide drugs are being manufactured illicitly, and in some cases they are being made available to the public before entering or completing clinical trials. At the request of Norwegian police and customs authorities, unknown pharmaceutical preparations suspected to contain peptide drugs are regularly subjected to analysis. In 2009, an unknown pharmaceutical preparation was submitted for analysis by liquid chromatography-high resolution tandem mass spectrometry (LC-HRMS/MS). The preparation was found to contain a 29 amino acid peptide with a C-terminal amide function. Based on the interpretation of mass spectrometric data, an amino acid sequence was proposed. The sequence is consistent with a peptide currently marketed under the name CJC-1295. CJC-1295 is a releasing factor for growth hormone and is therefore considered a Prohibited Substance under Section S2 of the WADA Prohibited List. This substance has potential performance-enhancing effects, it is readily available, and there is reason to believe that it is being used within the bodybuilding community. Copyright © 2010 John Wiley & Sons, Ltd.

  1. Growth hormone-releasing hormone as an agonist of the ghrelin receptor GHS-R1a.

    Casanueva, Felipe F; Camiña, Jesus P; Carreira, Marcos C; Pazos, Yolanda; Varga, Jozsef L; Schally, Andrew V

    2008-12-23

    Ghrelin synergizes with growth hormone-releasing hormone (GHRH) to potentiate growth hormone (GH) response through a mechanism not yet fully characterized. This study was conducted to analyze the role of GHRH as a potential ligand of the ghrelin receptor, GHS-R1a. The results show that hGHRH(1-29)NH(2) (GHRH) induces a dose-dependent calcium mobilization in HEK 293 cells stably transfected with GHS-R1a an effect not observed in wild-type HEK 293 cells. This calcium rise is also observed using the GHRH receptor agonists JI-34 and JI-36. Radioligand binding and cross-linking studies revealed that calcium response to GHRH is mediated by the ghrelin receptor GHS-R1a. GHRH activates the signaling route of inositol phosphate and potentiates the maximal response to ghrelin measured in inositol phosphate turnover. The presence of GHRH increases the binding capacity of (125)I-ghrelin in a dose dependent-fashion showing a positive binding cooperativity. In addition, confocal microscopy in CHO cells transfected with GHS-R1a tagged with enhanced green fluorescent protein shows that GHRH activates the GHS-R1a endocytosis. Furthermore, the selective GHRH-R antagonists, JV-1-42 and JMR-132, act also as antagonists of the ghrelin receptor GHS-R1a. Our findings suggest that GHRH interacts with ghrelin receptor GHS-R1a, and, in consequence, modifies the ghrelin-associated intracellular signaling pathway. This interaction may represent a form of regulation, which could play a putative role in the physiology of GH regulation and appetite control.

  2. Synthetic Growth Hormone-Releasing Peptides (GHRPs: A Historical Appraisal of the Evidences Supporting Their Cytoprotective Effects

    Jorge Berlanga-Acosta

    2017-02-01

    Full Text Available Background: Growth hormone-releasing peptides (GHRPs constitute a group of small synthetic peptides that stimulate the growth hormone secretion and the downstream axis activity. Mounting evidences since the early 1980s delineated unexpected pharmacological cardioprotective and cytoprotective properties for the GHRPs. However, despite intense basic pharmacological research, alternatives to prevent cell and tissue demise before lethal insults have remained as an empty niche in the clinical armamentarium. Here, we have rigorously reviewed the investigational development of GHRPs and their clinical niching perspectives. Methodology: PubMed/MEDLINE databases, including original research and review articles, were explored. The search design was date escalated from 1980 and included articles in English only. Results and Conclusions: GHRPs bind to two different receptors (GHS-R1a and CD36, which redundantly or independently exert relevant biological effects. GHRPs’ binding to CD36 activates prosurvival pathways such as PI-3K/AKT1, thus reducing cellular death. Furthermore, GHRPs decrease reactive oxygen species (ROS spillover, enhance the antioxidant defenses, and reduce inflammation. These cytoprotective abilities have been revealed in cardiac, neuronal, gastrointestinal, and hepatic cells, representing a comprehensive spectrum of protection of parenchymal organs. Antifibrotic effects have been attributed to some of the GHRPs by counteracting fibrogenic cytokines. In addition, GHRP family members have shown a potent myotropic effect by promoting anabolia and inhibiting catabolia. Finally, GHRPs exhibit a broad safety profile in preclinical and clinical settings. Despite these fragmented lines incite to envision multiple pharmacological uses for GHRPs, especially as a myocardial reperfusion damage-attenuating candidate, this family of “drugable” peptides awaits for a definitive clinical niche.

  3. Synthetic Growth Hormone-Releasing Peptides (GHRPs): A Historical Appraisal of the Evidences Supporting Their Cytoprotective Effects.

    Berlanga-Acosta, Jorge; Abreu-Cruz, Angel; Herrera, Diana García-Del Barco; Mendoza-Marí, Yssel; Rodríguez-Ulloa, Arielis; García-Ojalvo, Ariana; Falcón-Cama, Viviana; Hernández-Bernal, Francisco; Beichen, Qu; Guillén-Nieto, Gerardo

    2017-01-01

    Growth hormone-releasing peptides (GHRPs) constitute a group of small synthetic peptides that stimulate the growth hormone secretion and the downstream axis activity. Mounting evidences since the early 1980s delineated unexpected pharmacological cardioprotective and cytoprotective properties for the GHRPs. However, despite intense basic pharmacological research, alternatives to prevent cell and tissue demise before lethal insults have remained as an empty niche in the clinical armamentarium. Here, we have rigorously reviewed the investigational development of GHRPs and their clinical niching perspectives. PubMed/MEDLINE databases, including original research and review articles, were explored. The search design was date escalated from 1980 and included articles in English only. GHRPs bind to two different receptors (GHS-R1a and CD36), which redundantly or independently exert relevant biological effects. GHRPs' binding to CD36 activates prosurvival pathways such as PI-3K/AKT1, thus reducing cellular death. Furthermore, GHRPs decrease reactive oxygen species (ROS) spillover, enhance the antioxidant defenses, and reduce inflammation. These cytoprotective abilities have been revealed in cardiac, neuronal, gastrointestinal, and hepatic cells, representing a comprehensive spectrum of protection of parenchymal organs. Antifibrotic effects have been attributed to some of the GHRPs by counteracting fibrogenic cytokines. In addition, GHRP family members have shown a potent myotropic effect by promoting anabolia and inhibiting catabolia. Finally, GHRPs exhibit a broad safety profile in preclinical and clinical settings. Despite these fragmented lines incite to envision multiple pharmacological uses for GHRPs, especially as a myocardial reperfusion damage-attenuating candidate, this family of "drugable" peptides awaits for a definitive clinical niche.

  4. Antiproliferative effect of growth hormone-releasing hormone (GHRH antagonist on ovarian cancer cells through the EGFR-Akt pathway

    Varga Jozsef

    2010-05-01

    Full Text Available Abstract Background Antagonists of growth hormone-releasing hormone (GHRH are being developed for the treatment of various human cancers. Methods MTT assay was used to test the proliferation of SKOV3 and CaOV3. The splice variant expression of GHRH receptors was examined by RT-PCR. The expression of protein in signal pathway was examined by Western blotting. siRNA was used to block the effect of EGFR. Results In this study, we investigated the effects of a new GHRH antagonist JMR-132, in ovarian cancer cell lines SKOV3 and CaOV3 expressing splice variant (SV1 of GHRH receptors. MTT assay showed that JMR-132 had strong antiproliferative effects on SKOV3 and CaOV3 cells in both a time-dependent and dose-dependent fashion. JMR-132 also induced the activation and increased cleaved caspase3 in a time- and dose-dependent manner in both cell lines. In addition, JMR-132 treatments decreased significantly the epidermal growth factor receptor (EGFR level and the phosphorylation of Akt (p-Akt, suggesting that JMR-132 inhibits the EGFR-Akt pathway in ovarian cancer cells. More importantly, treatment of SKOV3 and CaOV3 cells with 100 nM JMR-132 attenuated proliferation and the antiapoptotic effect induced by EGF in both cell lines. After the knockdown of the expression of EGFR by siRNA, the antiproliferative effect of JMR-132 was abolished in SKOV3 and CaOV3 cells. Conclusions The present study demonstrates that the inhibitory effect of the GHRH antagonist JMR-132 on proliferation is due, in part, to an interference with the EGFR-Akt pathway in ovarian cancer cells.

  5. Evaluation of in vivo [corrected] biological activity of new agmatine analogs of growth hormone-releasing hormone (GH-RH)

    Bokser, L; Zarandi, M; Schally, A V

    1990-01-01

    The effects of agmatine analogs of growth hormone releasing hormone (GH-RH) were compared to GH-RH(1-29)-NH2 after intravenous (iv) and subcutaneous (sc) administration to pentobarbital-anesthetized male rats. After the iv injection, the analogs [desNH2-Tyr1,Ala15,Nle27] GH-RH(1-28)Agm (MZ-2-51); [desNH2-Tyr1,D-Lys12,Ala15,Nle27] GH-RH(1-28)Agm (MZ-2-57); [desNH2-Tyr1,Ala15,D-Lys21,Nle27] GH-RH(1-28)Agm (MZ-2-75) and [desNH2-Tyr1, D-Lys12,21, Ala15, Nle27] GH-RH(1-28)Agm (MZ-2-87) showed a potency equivalent to 4.4, 1.9, 1.07 and 1.03 times that of GH-RH (1-29)-NH2, respectively, at 5 min and 5.6, 1.8, 1.9 and 1.8 times higher, respectively, at 15 min. After sc administration, analogs MZ-2-51, MZ-2-57 and MZ-2-75 showed to be 34.3, 14.3 and 10.5 times more potent than the parent hormone at 15 min and 179.1, 88.9 and 45.0 times more active, respectively, at 30 min. In addition, MZ-2-51 had prolonged GH-releasing activity as compared to the standard. We also compared the activity of MZ-2-51 and MZ-2-57 with their homologous L-Arg and D-Arg analogs [desNH2-Tyr1,Ala15,Nle27] GH-RH(1-29)-NH2 (MZ-2-117), [des-NH2Tyr1,D-Lys12, Ala15, Nle27] GH-RH(1-29)NH2 (MZ-2-123) and [desNH2-Tyr1,D-Lys12,Ala15, Nle27,D-Arg29] GH-RH(1-29)NH2 (MZ-2-135) after intramuscular (im) injection. MZ-2-51 induced a somewhat greater GH release than MZ-2-117 at 15 min, both responses being larger than the controls (p less than 0.01) at 15 and 30 min. MZ-2-57, MZ-2-123 and MZ-2-135 given i.m. were able to stimulate GH release only at 15 minutes (p less than 0.05). Animals injected i.m. with MZ-2-51, but not with MZ-2-117, showed GH levels significantly higher than the control group (p less than 0.05) at 60 min. GH-RH(1-29)NH2 had low activity intramuscularly when tested at a dose of 2.5 micrograms. No toxic effects were observed after the iv administration of 1 mg/kg of Agm GH-RH analogs. These results indicate that our Agm analogs are active iv, sc and im and that the substitutions made in these

  6. Differential effects of 18- and 24-Gy cranial irradiation on growth rate and growth hormone release in children with prolonged survival after acute lymphocytic leukemia

    Cicognani, A.; Cacciari, E.; Vecchi, V.; Cau, M.; Balsamo, A.; Pirazzoli, P.; Tosi, M.T.; Rosito, P.; Paolucci, G.

    1988-01-01

    To evaluate the effects of two different doses of cranial irradiation on growth and growth hormone (GH) release, we studied 61 children with acute lymphocytic leukemia who had survived at least five years in continuous complete remission. Forty-three children received 24 Gy (group 1) and 18 children received 18 Gy (group 2). Height was evaluated at diagnosis, at the end of treatment, and 6, 12, and 24 months later. Growth hormone release was evaluated by arginine and levodopa tests after the end of treatment. After diagnosis, the height SD score decreased significantly in both groups; two years after the end of treatment, only group 1 showed an SD score for height that was still significantly lower than at diagnosis. Group 1 showed impaired GH responses to the tests and, compared with controls, group 1 in fact included a percentage of subjects with a normal response to levodopa (ie, greater than 8 micrograms/L) that was significantly lower (56.4% vs 83.3%) and a percentage of nonresponders to both tests that was significantly higher (21.6% vs 0%). These data indicate that only patients treated with lower cranial irradiation dosage (18 Gy) had complete growth recovery and normal GH responses to pharmacologic tests

  7. Evaluation of growth hormone release and human growth hormone treatment in children with cranial irradiation-associated short stature

    Romshe, C.A.; Zipf, W.B.; Miser, A.; Miser, J.; Sotos, J.F.; Newton, W.A.

    1984-01-01

    We studied nine children who had received cranial irradiation for various malignancies and subsequently experienced decreased growth velocity. Their response to standard growth hormone stimulation and release tests were compared with that in seven children with classic GH deficiency and in 24 short normal control subjects. With arginine and L-dopa stimulation, six of nine patients who received radiation had a normal GH response (greater than 7 ng/ml), whereas by design none of the GH deficient and all of the normal children had a positive response. Only two of nine patients had a normal response to insulin hypoglycemia, with no significant differences in the mean maximal response of the radiation and the GH-deficient groups. Pulsatile secretion was not significantly different in the radiation and GH-deficient groups, but was different in the radiation and normal groups. All subjects in the GH-deficient and radiation groups were given human growth hormone for 1 year. Growth velocity increased in all, with no significant difference in the response of the two groups when comparing the z scores for growth velocity of each subject's bone age. We recommend a 6-month trial of hGH in children who have had cranial radiation and are in prolonged remission with a decreased growth velocity, as there is no completely reliable combination of GH stimulation or release tests to determine their response

  8. Growth hormone-releasing peptide-biotin conjugate stimulates myocytes differentiation through insulin-like growth factor-1 and collagen type I.

    Lim, Chae Jin; Jeon, Jung Eun; Jeong, Se Kyoo; Yoon, Seok Jeong; Kwon, Seon Deok; Lim, Jina; Park, Keedon; Kim, Dae Yong; Ahn, Jeong Keun; Kim, Bong-Woo

    2015-09-01

    Based on the potential beneficial effects of growth hormone releasing peptide (GHRP)-6 on muscle functions, a newly synthesized GHRP-6-biotin conjugate was tested on cultured myoblast cells. Increased expression of myogenic marker proteins was observed in GHRP-6-biotin conjugate-treated cells. Additionally, increased expression levels of insulin-like growth factor-1 and collagen type I were observed. Furthermore, GHRP-6-biotin conjugate-treated cells showed increased metabolic activity, as indicated by increased concentrations of energy metabolites, such as ATP and lactate, and increased enzymatic activity of lactate dehydrogenase and creatine kinase. Finally, binding protein analysis suggested few candidate proteins, including desmin, actin, and zinc finger protein 691 as potential targets for GHRP6-biotin conjugate action. These results suggest that the newly synthesized GHRP-6-biotin conjugate has myogenic stimulating activity through, at least in part, by stimulating collagen type I synthesis and several key proteins. Practical applications of the GHRP-6-biotin conjugate could include improving muscle condition.

  9. Plasma growth hormone response to human growth hormone releasing factor in rats administered with chlorpromazine and antiserum against somatostatin. Effects of hypo- and hyperthyroidism.

    Wakabayashi, I; Tonegawa, Y; Ihara, T; Hattori, M; Shibasaki, T; Ling, N

    1985-10-01

    The effect of hypo- and hyperthyroidism on the plasma growth hormone (GH) response to synthetic human growth hormone releasing factor (GRF) was determined in conscious, freely moving rats pretreated with chlorpromazine and antiserum against somatostatin. Chlorpromazine plus somatostatin antiserum pretreated rats gave consistent response to GRF which was not observed in untreated rats. Chlorpromazine alone has no effect on GH secretion induced by GRF in rat pituitary monolayer culture. In rats made hypothyroid by thyroidectomy, both basal and peak plasma GH responses to a small (0.25 microgram/kg bw) and a moderate dose of GRF (1 microgram/kg bw) were significantly reduced as compared to controls. In rats made hyperthyroid by the administration of thyroxine, basal and peak plasma GH responses to a small but not to a moderate dose of GRF were significantly reduced as compared to controls. A reduced plasma GH response to a small dose of GRF was observed 8 days after the cessation of thyroxine administration. The pituitary GH reserve was markedly reduced in hypothyroid but not in hyperthyroid rats as compared to their respective controls. These results indicate that plasma GH response to GRF is reduced both in hypo- and hyperthyroidism. The mechanism involved in the phenomenon appears to be different between the two conditions.

  10. The interrelationships of thyroid and growth hormones: effect of growth hormone releasing hormone in hypo- and hyperthyroid male rats.

    Root, A W; Shulman, D; Root, J; Diamond, F

    1986-01-01

    Growth hormone (GH) and the thyroid hormones interact in the hypothalamus, pituitary and peripheral tissues. Thyroid hormone exerts a permissive effect upon the anabolic and metabolic effects of GH, and increases pituitary synthesis of this protein hormone. GH depresses the secretion of thyrotropin and the thyroid hormones and increases the peripheral conversion of thyroxine to triiodothyronine. In the adult male rat experimental hypothyroidism produced by ingestion of propylthiouracil depresses the GH secretory response to GH-releasing hormone in vivo and in vitro, reflecting the lowered pituitary stores of GH in the hypothyroid state. Short term administration of large amounts of thyroxine with induction of the hyperthyroid state does not affect the in vivo GH secretory response to GH-releasing hormone in this animal.

  11. Galanin does not affect the growth hormone-releasing hormone-stimulated growth hormone secretion in patients with hyperthyroidism.

    Giustina, A; Bussi, A R; Legati, F; Bossoni, S; Licini, M; Schettino, M; Zuccato, F; Wehrenberg, W B

    1992-12-01

    Patients with hyperthyroidism have reduced spontaneous and stimulated growth hormone (GH) secretion. The aim of our study was to evaluate the effects of galanin, a novel neuropeptide which stimulates GH secretion in man, on the GH response to GHRH in patients with hyperthyroidism. Eight untreated hyperthyroid patients with Graves' disease (6F, 2M, aged 25-50 years) and six healthy volunteers (3F, 3M, aged 27-76 years) underwent from -10 to 30 min in random order: (i) porcine galanin, iv, 500 micrograms in 100 ml saline; or (ii) saline, iv, 100 ml. A bolus of human GHRH(1-29)NH2, 100 micrograms, was injected iv at 0 min. Hyperthyroid patients showed blunted GH peaks after GHRH+saline (10.2 +/- 2.5 micrograms/l) compared to normal subjects (20.7 +/- 4.8 micrograms/l, p hyperthyroid subjects (12.5 +/- 3 micrograms/l) compared to normal subjects (43.8 +/- 6 micrograms/l, p hyperthyroidism suggests that hyperthyroxinemia may either increase the somatostatin release by the hypothalamus or directly affect the pituitary GH secretory capacity.

  12. Acute effects of clonidine and growth-hormone-releasing hormone on growth hormone secretion in patients with hyperthyroidism.

    Giustina, A; Buffoli, M G; Bussi, A R; Wehrenberg, W B

    1991-01-01

    Patients with hyperthyroidism have reduced growth hormone (GH) responses to pharmacological stimuli and reduced spontaneous nocturnal GH secretion. The stimulatory effect of clonidine on GH secretion has been suggested to depend on an enhancement of hypothalamic GH-releasing hormone (GHRH) release. The aim of our study was to evaluate the effects of clonidine and GHRH on GH secretion in patients with hyperthyroidism. Eight hyperthyroid females with recent diagnosis of Graves' disease (age range 20-55 years, body mass index range 19.2-26.2 kg/m2) and 6 healthy female volunteers (age range 22-35 years, body mass index range 19-25 kg/m2) underwent two experimental trials at no less than 7-day intervals: (a) an intravenous infusion of clonidine 150 micrograms in 10 ml of saline, or (b) a bolus intravenous injection of human GHRH (1-29)NH2, 100 micrograms in 1 ml of saline. Hyperthyroid patients showed blunted GH peaks after clonidine (7.1 +/- 1.7 micrograms/l) as compared to normal subjects receiving clonidine (28.5 +/- 4.9 micrograms/l, p less than 0.05). GH peaks after GHRH were also significantly lower in hyperthyroid subjects (8.0 +/- 1.7 micrograms/l) as compared to normal subjects receiving GHRH (27.5 +/- 4.4 micrograms/l, p less than 0.05). No significant differences in the GH values either after clonidine or GHRH were observed in the two groups of subjects examined. Our data demonstrate that the GH responses to clonidine as well as to GHRH in patients with hyperthyroidism are inhibited in a similar fashion with respect to normal subjects.(ABSTRACT TRUNCATED AT 250 WORDS)

  13. [The changes of ghrelin, growth hormone, growth hormone releasing hormone and their clinical significances in patients with chronic obstructive pulmonary disease].

    Xu, Zhi-song; Bao, Zi-yu; Wang, Zhi-ying; Yang, Guo-jun; Zhu, Dong-fang; Zhang, Li; Tan, Rong-mei

    2012-07-01

    To investigate the changes of plasma ghrelin, growth hormone (GH) and growth hormone releasing hormone (GHRH) and gastric ghrelin in patients with chronic obstructive pulmonary disease (COPD) and to explore their clinical significances. Plasma ghrelin, GH, GHRH, TNFα, IL-6 and C reactive protein (CRP) were measured in 40 COPD patients and 20 controls with chronic bronchitis. Correlated factors of plasma ghrelin, TNFα, IL-6, CRP were analyzed. Body composition was assessed with bioelectrical impedance analysis. The expression of gastric ghrelin in patients with COPD was detected. Plasma ghrelin was higher in the underweight patients than in the normal weight patients and in the controls [(1.78 ± 0.46) ng/L, (1.39 ± 0.46) ng/L, (1.36 ± 0.39) ng/L, respectively]. Plasma GH was lower in the underweight patients than in the normal weight patients and in the controls [(4.12 ± 0.83) µg/L, (5.17 ± 0.72)µg/L, (6.49 ± 1.13) µg/L, respectively]. Plasma GHRH was lower in the underweight patients than in the normal weight patients and in the controls [(20.43 ± 4.41) ng/L, (23.47 ± 3.97) ng/L, (27.48 ± 10.06) ng/L, respectively]. Plasma ghrelin was higher in the underweight patients than in the controls (P 0.05). Plasma ghrelin was positively correlated with TNFα and IL-6 in the underweight patients. The gastric expression of ghrelin showed no evident difference between the patients with COPD and the controls. The plasma GH in COPD patients may not be correlated with ghrelin. The plasma ghrelin level may be a useful indicator for malnutrition in COPD patients. Plasma ghrelin might be involved in the pathogenesis of CODP by affecting the body energy metabolism.

  14. Does growth hormone releasing factor desensitize the somatotroph? Interpretation of responses of growth hormone during and after 10-hour infusion of GRF 1-29 amide in man.

    Davis, J R; Sheppard, M C; Shakespear, R A; Lynch, S S; Clayton, R N

    1986-02-01

    It is unclear whether growth hormone releasing factor (GRF) administration in vivo may desensitize the somatotroph. To investigate this possibility we have examined the effects of 10-h infusion of the equipotent 1-29 amide analogue of hpGRF on serum GH levels and on the subsequent GH response to a bolus dose of GRF (1-29). Four normal adult males received an intravenous infusion of 1-29 GRF (1 microgram/kg/h) from 0800 to 1800 h, with blood samples taken at 10 min intervals. A 100 micrograms intravenous bolus dose of GRF was given at 1800 h, and sampling continued for a further 90 min. GH levels were near or below the limit of detection (0.5 mU/l) throughout the control 10 h period. During GRF infusion there was increased GH release with pulses of irregular frequency and amplitude (up to 80 mU/l) continuing throughout the entire infusion period. There was no apparent reduction in total GH released towards the latter part of the infusion. On the control day, 100 micrograms GRF bolus increased mean (+/- SEM) GH from 0.82 +/- 0.21 mU/l to a peak of 59.0 +/- 44.8 mU/l (P less than 0.002). Following 10-GRF infusion, responses to bolus injection of GRF were reduced, but variable. In two subjects a small rise in GH levels occurred (basal 6.4 and 7.2 rising to peak values of 11.2 and 23.0 mU/l respectively). In the other two subjects, GH levels fell but in these the GRF bolus had coincided with a GH peak. The loss of GRF responsiveness after GRF infusion may be due to 'desensitization'.(ABSTRACT TRUNCATED AT 250 WORDS)

  15. Kisspeptin stimulates growth hormone release by utilizing Neuropeptide Y pathways and is dependent on the presence of ghrelin

    Although kisspeptin is the primary stimulator of gonadotropin releasing hormone secretion and therefore the hypothalamic-pituitary gonadal axis, new findings suggest kisspeptin can also regulate additional neuroendocrine processes including release of growth hormone (GH). Central delivery of kisspep...

  16. Synthesis of human pancreatic growth hormone-releasing factor and two omission analogs by segment-coupling method in aqueous solution

    Blake, J.; Westphal, M.; Li, C.H. (Laboratory of Molecular Endocrinology, University of California, San Francisco, USA)

    1984-01-01

    The human growth hormone-releasing factor (GRF) peptides (GlyS/sup 15/)-GRF-(1-15) (IV), trifluoroacetyl-GRF-(20-44) (VI), trifluoroacetyl-GRF-(18-44) (VIII), and trifluoroacetyl-GRF-(16-44) (X) were synthesized by the solidphase method. Each of the peptides was reacted with citraconic anhydride and the trifluoroacetyl group was removed by reaction with 10% hydrazine in water. The citraconylated GRF-(1-15) peptide was coupled to the (20-44), (18-44) or (16-44) peptides by reaction with silver nitrate/N-hydroxysuccinimide to give GRF-(1-15)-(20-44) (XII), GRF-(1-15)-(18-44) (XIII), or GRF-(1-44), respectively. GRF-(1-44) was shown to stimulate the release of rat growth hormone from rat pituitary cells with an ED/sub 50/=8.8 x 10/sup -11/M. Peptides XII and XIII were inactive, either as agonists or as antagonists of the action of GRF-(1-44).

  17. Androgen-dependent somatotroph function in a hypogonadal adolescent male: evidence for control of exogenous androgens on growth hormone release

    Mauras, N.; Blizzard, R.M.; Rogol, A.D.

    1989-01-01

    A 14(10/12)-year-old white male with primary gonadal failure following testicular irradiation for acute lymphocytic leukemia was evaluated for poor growth. He had received 2400 rad of prophylactic cranial irradiation. The growth velocity had decelerated from 7 to 3.2 cm/yr over 3 years. His bone age was 12(0/12) years (by TW2-RUS), and his peak growth hormone (GH) response to provocative stimuli was 1.4 ng/mL. The 24-hour GH secretion was studied by drawing blood every 20 minutes for 24 hours. The resulting GH profile was analyzed by a computerized pulse detection algorithm, CLUSTER. Timed serum GH samples were also obtained after a 1 microgram/kg IV bolus injection of the GH releasing factor (GRH). The studies showed a flat 24-hour profile and a peak GH response to GRH of 3.9 ng/ml. Testosterone enanthate treatment was started, 100 mg IM every 4 weeks. Ten months after the initiation of therapy the calculated growth rate was 8.6 cm/yr. The 24-hour GH study and GRH responses were repeated at the time, showing a remarkably normal 24-hour GH secretory pattern and a peak GH response to GRH of 14.4 ng/mL. Testosterone therapy was discontinued, and 4 months later similar studies were repeated. A marked decrease in the mean 24-hour GH secretion and mean peak height occurred, but with maintenance of the GH pulse frequency. The GH response to GRH was intermediate, with a peak of 8 ng/mL. There was no further growth during those 4 months despite open epiphyses

  18. Effect of aging on GHRF-induced growth hormone release from anterior pituitary cells in primary culture

    Spik, K.W.; Boyd, R.L.; Sonntag, W.E.

    1991-01-01

    Five criteria were developed to validate the primary cell culture model for comparison of GRF-induced release of growth hormone in pituitary tissue from aging animals. Pituitaries from young (5-mo), middle-aged (14-mo), and old (24-mo) male Fischer 344 rats were dispersed using either trypsin/trypsin inhibitor or dispase and compared with respect to the number of pituitary cells recovered, cell viability, 3H-leucine incorporation into total protein, time course for recovery of optimal response to GRF, and the dose-relationship for GRF-induced release of growth hormone 2, 4, and 6 days after dispersal. Results indicated that direct comparison of cellular responses between tissues from young, middle-aged, and old rats in primary cell culture is confounded by variations in time for recovery of optimal responses, the effects of the enzymes used for dispersal, and the methods used to express the data

  19. Effects of long-term treatment with growth hormone-releasing peptide-2 in the GHRH knockout mouse.

    Alba, Maria; Fintini, Danilo; Bowers, Cyril Y; Parlow, A F; Salvatori, Roberto

    2005-11-01

    Growth hormone (GH) secretagogues (GHS) stimulate GH secretion in vivo in humans and in animals. They act on the ghrelin receptor, expressed in both the hypothalamus and the pituitary. It is unknown whether GHSs act predominantly by increasing the release of hypothalamic GH-releasing hormone (GHRH) or by acting directly on the somatotroph cells. We studied whether a potent GHS could stimulate growth in the absence of endogenous GHRH. To this end, we used GHRH knockout (GHRH-KO) mice. These animals have proportionate dwarfism due to severe GH deficiency (GHD) and pituitary hypoplasia due to reduced somatotroph cell mass. We treated male GHRH-KO mice for 6 wk (from week 1 to week 7 of age) with GH-releasing peptide-2 (GHRP-2, 10 microg s.c. twice a day). Chronic treatment with GHRP-2 failed to stimulate somatotroph cell proliferation and GH secretion and to promote longitudinal growth. GHRP-2-treated mice showed an increase in total body weight compared with placebo-treated animals, due to worsening of the body composition alterations typical of GHD animals. These data demonstrate that GHRP-2 failed to reverse the severe GHD caused by lack of GHRH.

  20. Relationship between nitric oxide- and calcium-dependent signal transduction pathways in growth hormone release from dispersed goldfish pituitary cells.

    Chang, John P; Sawisky, Grant R; Davis, Philip J; Pemberton, Joshua G; Rieger, Aja M; Barreda, Daniel R

    2014-09-15

    Nitric oxide (NO) and Ca(2+) are two of the many intracellular signal transduction pathways mediating the control of growth hormone (GH) secretion from somatotropes by neuroendocrine factors. We have previously shown that the NO donor sodium nitroprusside (SNP) elicits Ca(2+) signals in identified goldfish somatotropes. In this study, we examined the relationships between NO- and Ca(2+)-dependent signal transduction mechanisms in GH secretion from primary cultures of dispersed goldfish pituitary cells. Morphologically identified goldfish somatotropes stained positively for an NO-sensitive dye indicating they may be a source of NO production. In 2h static incubation experiments, GH release responses to the NO donor S-nitroso-N-acetyl-d,l-penicillamine (SNAP) were attenuated by CoCl2, nifedipine, verapamil, TMB-8, BHQ, and KN62. In column perifusion experiments, the ability of SNP to induce GH release was impaired in the presence of TMB-8, BHQ, caffeine, and thapsigargin, but not ryanodine. Caffeine-elicited GH secretion was not affected by the NO scavenger PTIO. These results suggest that NO-stimulated GH release is dependent on extracellular Ca(2+) availability and voltage-sensitive Ca(2+) channels, as well as intracellular Ca(2+) store(s) that possess BHQ- and/or thapsigargin-inhibited sarcoplasmic/endoplasmic reticulum Ca(2+)-ATPases, as well as TMB-8- and/or caffeine-sensitive, but not ryanodine-sensitive, Ca(2+)-release channels. Calmodulin kinase-II also likely participates in NO-elicited GH secretion but caffeine-induced GH release is not upstream of NO production. These findings provide insights into how NO actions many integrate with Ca(2+)-dependent signalling mechanisms in goldfish somatotropes and how such interactions may participate in the GH-releasing actions of regulators that utilize both NO- and Ca(2+)-dependent transduction pathways. Copyright © 2014 Elsevier Inc. All rights reserved.

  1. Determination of growth hormone releasing peptides (GHRP) and their major metabolites in human urine for doping controls by means of liquid chromatography mass spectrometry.

    Thomas, Andreas; Höppner, Sebastian; Geyer, Hans; Schänzer, Wilhelm; Petrou, Michael; Kwiatkowska, Dorota; Pokrywka, Andrzej; Thevis, Mario

    2011-08-01

    A family of small peptides has reached the focus of doping controls representing a comparably new strategy for cheating sportsmen. These growth hormone releasing peptides (GHRP) are orally active and induce an increased production of endogenous growth hormone (GH). While the established test for exogenous GH fails, the misuse of these prohibited substances remains unrecognized. The present study provides data for the efficient extraction of a variety of known drug candidates (GHRP-1, GHRP-2, GHRP-4, GHRP-5, GHRP-6, alexamorelin, ipamorelin, and hexarelin) from human urine with subsequent mass spectrometric detection after liquid chromatographic separation. The used method potentially enables the retrospective evaluation of the acquired data for unknown metabolites by means of a non-targeted approach with high-resolution/high-accuracy full-scan mass spectrometry with additional higher collision energy dissociation experiments. This is of great importance due to the currently unknown metabolism of most of the targets and, thus, the method is focused on the intact peptidic drugs. Only the already characterised major metabolite of GHRP-2 (D-Ala-D-2-naphthylAla-L-Ala, as well as its stable isotope-labelled analogue) was synthesised and implemented in the detection assay. Method validation for qualitative purpose was performed with respect to specificity, precision (<20%), intermediate precision (<20%), recovery (47-95%), limit of detection (0.2-1 ng/mL), linearity, ion suppression and stability. Two stable isotope-labelled internal standards were used (deuterium-labelled GHRP-4 and GHRP-2 metabolite). The proof-of-principle was obtained by the analysis of excretion study urine samples obtained from a single oral administration of 10 mg of GHRP-2. Here, the known metabolite was detectable over 20 h after administration while the intact drug was not observed.

  2. Diagnostic challenges and management of a patient with acromegaly due to ectopic growth hormone-releasing hormone secretion from a bronchial carcinoid tumour

    Nikolaos Kyriakakis

    2017-01-01

    Full Text Available A male patient presented at the age of 30 with classic clinical features of acromegaly and was found to have elevated growth hormone levels, not suppressing during an oral glucose tolerance test. His acromegaly was originally considered to be of pituitary origin, based on a CT scan, which was interpreted as showing a pituitary macroadenoma. Despite two trans-sphenoidal surgeries, cranial radiotherapy and periods of treatment with bromocriptine and octreotide, his acromegaly remained active clinically and biochemically. A lung mass was discovered incidentally on a chest X-ray performed as part of a routine pre-assessment for spinal surgery 5 years following the initial presentation. This was confirmed to be a bronchial carcinoid tumour, which was strongly positive for growth hormone-releasing hormone (GHRH and somatostatin receptor type 2 by immunohistochemistry. The re-examination of the pituitary specimens asserted the diagnosis of pituitary GH hyperplasia. Complete resolution of the patient’s acromegaly was achieved following right lower and middle lobectomy. Seventeen years following the successful resection of the bronchial carcinoid tumour the patient remains under annual endocrine follow-up for monitoring of the hypopituitarism he developed after the original interventions to his pituitary gland, while there has been no evidence of active acromegaly or recurrence of the carcinoid tumour. Ectopic acromegaly is extremely rare, accounting for <1% of all cases of acromegaly. Our case highlights the diagnostic challenges differentiating between ectopic acromegaly and acromegaly of pituitary origin and emphasises the importance of avoiding unnecessary pituitary surgery and radiotherapy. The role of laboratory investigations, imaging and histology as diagnostic tools is discussed.

  3. The effect of short-term cortisol changes on growth hormone responses to the pyridostigmine-growth-hormone-releasing-hormone test in healthy adults and patients with suspected growth hormone deficiency

    Andersen, M; Støving, R K; Hangaard, J

    1998-01-01

    BACKGROUND AND AIMS: The interaction between cortisol and growth hormone (GH)-levels may significantly influence GH-responses to a stimulation test. In order to systematically analyse the interaction in a paired design, it is necessary to use a test, which has been proven safe and reliable...... such as the pyridostigmine-growth-hormone-releasing-hormone (PD-GHRH) test. Three groups of subjects with a different GH-secretory capacity were included. STUDY A: Eight healthy adults were tested seven times, once with placebo throughout the examination and six times with the PD-GHRH test following no glucocorticoid......-responses to a PD-GHRH test were reduced in all individuals during acute stress-appropriate cortisol levels and the percentage reduction in GH-levels was independent of the GH-secretory capacity. Clinically, we found that peak GH-responses were not significantly affected by a short break in conventional HC therapy...

  4. Growth hormone-releasing hormone promotes survival of cardiac myocytes in vitro and protects against ischaemia-reperfusion injury in rat heart.

    Granata, Riccarda; Trovato, Letizia; Gallo, Maria Pia; Destefanis, Silvia; Settanni, Fabio; Scarlatti, Francesca; Brero, Alessia; Ramella, Roberta; Volante, Marco; Isgaard, Jorgen; Levi, Renzo; Papotti, Mauro; Alloatti, Giuseppe; Ghigo, Ezio

    2009-07-15

    The hypothalamic neuropeptide growth hormone-releasing hormone (GHRH) stimulates GH synthesis and release in the pituitary. GHRH also exerts proliferative effects in extrapituitary cells, whereas GHRH antagonists have been shown to suppress cancer cell proliferation. We investigated GHRH effects on cardiac myocyte cell survival and the underlying signalling mechanisms. Reverse transcriptase-polymerase chain reaction analysis showed GHRH receptor (GHRH-R) mRNA in adult rat ventricular myocytes (ARVMs) and in rat heart H9c2 cells. In ARVMs, GHRH prevented cell death and caspase-3 activation induced by serum starvation and by the beta-adrenergic receptor agonist isoproterenol. The GHRH-R antagonist JV-1-36 abolished GHRH survival action under both experimental conditions. GHRH-induced cardiac cell protection required extracellular signal-regulated kinase (ERK)1/2 and phosphoinositide-3 kinase (PI3K)/Akt activation and adenylyl cyclase/cAMP/protein kinase A signalling. Isoproterenol strongly upregulated the mRNA and protein of the pro-apoptotic inducible cAMP early repressor, whereas GHRH completely blocked this effect. Similar to ARVMs, in H9c2 cardiac cells, GHRH inhibited serum starvation- and isoproterenol-induced cell death and apoptosis through the same signalling pathways. Finally, GHRH improved left ventricular recovery during reperfusion and reduced infarct size in Langendorff-perfused rat hearts, subjected to ischaemia-reperfusion (I/R) injury. These effects involved PI3K/Akt signalling and were inhibited by JV-1-36. Our findings suggest that GHRH promotes cardiac myocyte survival through multiple signalling mechanisms and protects against I/R injury in isolated rat heart, indicating a novel cardioprotective role of this hormone.

  5. Effects of growth hormone-releasing hormone on sleep and brain interstitial fluid amyloid-β in an APP transgenic mouse model.

    Liao, Fan; Zhang, Tony J; Mahan, Thomas E; Jiang, Hong; Holtzman, David M

    2015-07-01

    Alzheimer's disease (AD) is a neurodegenerative disorder characterized by impairment of cognitive function, extracellular amyloid plaques, intracellular neurofibrillary tangles, and synaptic and neuronal loss. There is substantial evidence that the aggregation of amyloid β (Aβ) in the brain plays a key role in the pathogenesis of AD and that Aβ aggregation is a concentration dependent process. Recently, it was found that Aβ levels in the brain interstitial fluid (ISF) are regulated by the sleep-wake cycle in both humans and mice; ISF Aβ is higher during wakefulness and lower during sleep. Intracerebroventricular infusion of orexin increased wakefulness and ISF Aβ levels, and chronic sleep deprivation significantly increased Aβ plaque formation in amyloid precursor protein transgenic (APP) mice. Growth hormone-releasing hormone (GHRH) is a well-documented sleep regulatory substance which promotes non-rapid eye movement sleep. GHRHR(lit/lit) mice that lack functional GHRH receptor have shorter sleep duration and longer wakefulness during light periods. The current study was undertaken to determine whether manipulating sleep by interfering with GHRH signaling affects brain ISF Aβ levels in APPswe/PS1ΔE9 (PS1APP) transgenic mice that overexpress mutant forms of APP and PSEN1 that cause autosomal dominant AD. We found that intraperitoneal injection of GHRH at dark onset increased sleep and decreased ISF Aβ and that delivery of a GHRH antagonist via reverse-microdialysis suppressed sleep and increased ISF Aβ. The diurnal fluctuation of ISF Aβ in PS1APP/GHRHR(lit/lit) mice was significantly smaller than that in PS1APP/GHRHR(lit/+) mice. However despite decreased sleep in GHRHR deficient mice, this was not associated with an increase in Aβ accumulation later in life. One of several possibilities for the finding is the fact that GHRHR deficient mice have GHRH-dependent but sleep-independent factors which protect against Aβ deposition. Copyright © 2014

  6. Inhibition of growth of experimental prostate cancer with sustained delivery systems (microcapsules and microgranules) of the luteinizing hormone-releasing hormone antagonist SB-75.

    Korkut, E; Bokser, L; Comaru-Schally, A M; Groot, K; Schally, A V

    1991-02-01

    Inhibitory effects of the sustained delivery systems (microcapsules and microgranules) of a potent antagonist of luteinizing hormone-releasing hormone N-Ac-[3-(2-naphthyl)-D-alanine1, 4-chloro-D-phenylalanine2, 3-(3-pyridyl)-D-alanine3, D-citrulline6, D-alanine10]LH-RH (SB-75) on the growth of experimental prostate cancers were investigated. In the first experiment, three doses of a microcapsule preparation releasing 23.8, 47.6, and 71.4 micrograms of antagonist SB-75 per day were compared with microcapsules of agonist [D-Trp6]LH-RH liberating 25 micrograms/day in rats bearing Dunning R3327H transplantable prostate carcinoma. During 8 weeks of treatment, tumor growth was decreased by [D-Trp6]LH-RH and all three doses of SB-75 as compared to untreated controls. The highest dose of SB-75 (71.4 micrograms/day) caused a greater inhibition of prostate cancer growth than [D-Trp6]LH-RH as based on measurement of tumor volume and percentage change in tumor volume. Doses of 23.8 and 47.6 micrograms of SB-75 per day induced a partial and submaximal decrease, respectively, in tumor weight and volume. Tumor doubling time was the longest (50 days) with the high dose of SB-75 vs. 15 days for controls. The body weights were unchanged. The weights of testes, seminal vesicles, and ventral prostate were greatly reduced in all three groups that received SB-75, and testosterone levels were decreased to nondetectable values in the case of the two higher doses of SB-75. LH levels were also diminished. Similar results were obtained in the second experiment, in which the animals were treated for a period of 8 weeks with microgranules of SB-75. Therapy with microgranules of SB-75 significantly decreased tumor growth as measured by the final tumor volume, the percentage change from the initial tumor volume, and the reduction in tumor weight. The results indicate that antagonist SB-75, released from sustained delivery systems, can produce a state of chemical castration and effectively

  7. Synthesis and in vitro and in vivo activity of analogs of growth hormone-releasing hormone (GH-RH) with C-terminal agmatine.

    Zarandi, M; Csernus, V; Bokser, L; Bajusz, S; Groot, K; Schally, A V

    1990-12-01

    In the search for more active analogs of human growth hormone-releasing hormone (GH-RH), 37 new compounds were synthesized by solid phase methodology, purified, and tested biologically. Most of the analogs contained a sequence of 27 amino acids and N-terminal desaminotyrosine (Dat) and C-terminal agmatine (Agm), which are not amino acids. In addition to Dat in position 1 and Agm in position 29, the majority of the analogs had Ala15 and Nle27 substitutions and one or more additional L- or D-amino acid modifications. [Dat1, Ala15, Nle27]GH-RH(1-28)Agm (MZ-2-51) was the most active analog. Its in vitro GH-releasing potency was 10.5 times higher than that of GH-RH(1-29)NH2 and in the i.v. in vivo assay, MZ-2-51 was 4-5 times more active than the standard. After s.c. administration to rats. MZ-2-51 showed an activity 34 times higher at 15 min and 179 times greater at 30 min than GH-RH(1-29)NH2 and also displayed a prolonged activity. D-Tyr10, D-Lys12, and D-Lys21 homologs of MZ-2-51 also showed enhanced activities. Thus, [Dat1, D-Tyr10, Ala15, Nle27]GH-RH(1-28)Agm (MZ-2-159), [Dat1, D-Lys12, Ala15, Nle27]GH-RH(1-28)AGM (MZ-2-57), and [Dat1, Ala15, D-Lys21, Nle27]GH-RH(1-28)Agm (MZ-2-75) were 4-6 times more active in vitro than GH-RH(1-29)NH2. In vivo, after i.v. administration, analog MZ-2-75 was equipotent and analogs MZ-2-159 and MZ-2-57 about twice as potent as the standard.(ABSTRACT TRUNCATED AT 250 WORDS)

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

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

    1995-01-01

    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...... 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...

  9. Growth Hormone-Releaser Diet Attenuates Cognitive Dysfunction in Klotho Mutant Mice via Insulin-Like Growth Factor-1 Receptor Activation in a Genetic Aging Model

    Seok Joo Park

    2014-09-01

    Full Text Available BackgroundIt has been recognized that a defect in klotho gene expression accelerates the degeneration of multiple age-sensitive traits. Accumulating evidence indicates that aging is associated with declines in cognitive function and the activity of growth hormone (GH/insulin-like growth factor-1 (IGF-1.MethodsIn this study, we examined whether a GH-releaser diet could be effective in protecting against cognitive impairment in klotho mutant mice.ResultsThe GH-releaser diet significantly induced the expression of IGF-1 and IGF-1 receptors in the hippocampus of klotho mutant mice. Klotho mutant mice showed significant memory impairments as compared with wild-type mice. In addition, the klotho mutation significantly decreased the expression of cell survival/antiapoptotic factors, including phospho-Akt (p-Akt/phospho-glycogen synthase kinase3β (p-GSK3β, phospho-extracellular signal-related kinase (p-ERK, and Bcl-2, but significantly increased those of cell death/proapoptotic factors, such as phospho-c-jun N-terminal kinase (p-JNK, Bax, and cleaved caspase-3 in the hippocampus. Treatment with GH-releaser diet significantly attenuated both decreases in the expression of cell survival/antiapoptotic factors and increases in the expression of cell death/proapoptotic factors in the hippocampus of klotho mutant mice. In addition, klotho mutation-induced oxidative stress was significantly attenuated by the GH-releaser diet. Consequently, a GH-releaser diet significantly improved memory function in the klotho mutant mice. GH-releaser diet-mediated actions were significantly reversed by JB-1, an IGF-1 receptor antagonist.ConclusionThe results suggest that a GH-releaser diet attenuates oxidative stress, proapoptotic changes and consequent dysfunction in klotho mutant mice by promoting IGF-1 expression and IGF-1 receptor activation.

  10. Effects of polybrominated diphenyl ethers (PBDEs) and their derivatives on protein disulfide isomerase activity and growth hormone release of GH3 cells.

    Hashimoto, Shoko; Yoshimura, Hiromi; Okada, Kazushi; Uramaru, Naoto; Sugihara, Kazumi; Kitamura, Shigeyuki; Imaoka, Susumu

    2012-03-19

    Polybrominated diphenyl ethers (PBDEs) have been used in a variety of consumer products such as flame retardants and recently have been known to be widespread environmental pollutants, which probably affect biological functions of mammalian cells. However, the risk posed by PBDE metabolites has not been clarified. Our previous study suggested that bisphenol A (BPA), an endocrine-disrupting chemical, binds to protein disulfide isomerase (PDI) and inhibits its activity. PDI is an isomerase enzyme in the endoplasmic reticulum and facilitates the formation or cleavage of disulfide bonds. PDI consists of a, b, b', and a' domains and the c region, with the a and a' domains having isomerase active sites. In the present study, we tested the effects of 10 kinds of PBDE compounds and their metabolites on PDI. OH-PBDEs specifically inhibited the isomerase activity of PDI, with 4'-OH-PBDE more effective than 2' (or 2)-OH-PBDEs. 4'-OH-PBDE inhibited the isomerase activity of the b'a'c fragment but not that of ab and a'c, suggesting that the b' domain of PDI is essential for the inhibition by 4'-OH-PBDE. We also investigated the effects of these chemicals on the production of growth hormone (GH) in GH3 cells. In GH3 cells, levels of mRNA and protein of GH stimulated by T(3) were reduced by 4'-OH-PBDE and 4'-MeO-PBDE. The reduction in GH expression caused by these compounds was not changed by the overexpression or knockdown of PDI in GH3 cells, while these manipulations of PDI levels significantly suppressed the expression of GH. These results suggest that the biological effects of PBDEs differed depending on their brominated and hydroxylated positions. © 2011 American Chemical Society

  11. Analogues of luteinizing hormone-releasing hormone containing cytotoxic groups.

    Janáky, T; Juhász, A; Bajusz, S; Csernus, V; Srkalovic, G; Bokser, L; Milovanovic, S; Redding, T W; Rékási, Z; Nagy, A

    1992-02-01

    In an attempt to produce better cytotoxic analogues, chemotherapeutic antineoplastic radicals including an alkylating nitrogen mustard derivative of D-phenylalanine (D-melphalan), reactive cyclopropane, anthraquinone derivatives [2-(hydroxymethyl)anthraquinone and the anticancer antibiotic doxorubicin], and an antimetabolite (methotrexate) were coupled to suitably modified agonists and antagonists of luteinizing hormone-releasing hormone (LH-RH). Analogues with D-lysine6 and D-ornithine6 or N epsilon-(2,3-diaminopropionyl)-D-lysine and N delta-(2,3-diaminopropionyl)-D-ornithine were used as carriers for one or two cytotoxic moieties. The enhanced biological activities produced by the incorporation of D amino acids into position 6 of the agonistic analogues were further increased by the attachment of hydrophobic cytotoxic groups, resulting in compounds with 10-50 times higher activity than LH-RH. Most of the monosubstituted agonistic analogues showed high affinities for the membrane receptors of human breast cancer cells, while the receptor binding affinities of peptides containing two cytotoxic side chains were lower. Antagonistic carriers [Ac-D-Nal(2)1,D-Phe(4Cl)2,D-Trp3,Arg5,D-Lys6,D-Ala10] LH-RH [where Nal(2) is 3-(2-naphthyl)alanine], [Ac-D-Nal(2)1,D-Phe(4Cl)2,D-Trp3,Arg5,N epsilon-(2,3-diaminopropionyl)-D-Lys6,D-Ala10]LH-RH, and their D-Pal(3)3 homologs [Pal(3) is 3-(3-pyridyl)alanine] as well as [Ac-D-Nal(2)1,D-Phe(4Cl)2,D-Pal(3)3,Tyr5,N epsilon-(2,3-diamino-propionyl)-D-Lys6,D-Ala10]LH-RH were linked to cytotoxic compounds. The hybrid molecules inhibited ovulation in rats at doses of 10 micrograms and suppressed LH release in vitro. The receptor binding of cytotoxic analogues was decreased compared to the precursor peptides, although analogues with 2-(hydroxymethyl)anthraquinone hemiglutarate had high affinities. All of the cytotoxic analogues tested inhibited [3H]thymidine incorporation into DNA in cultures of human breast and prostate cancer cell lines

  12. The growth hormone-releasing hormone (GHRH) antagonist JV-1-36 inhibits proliferation and survival of human ectopic endometriotic stromal cells (ESCs) and the T HESC cell line.

    Annunziata, Marta; Grande, Cristina; Scarlatti, Francesca; Deltetto, Francesco; Delpiano, Elena; Camanni, Marco; Ghigo, Ezio; Granata, Riccarda

    2010-08-01

    To determine the effect of the GHRH antagonist JV-1-36 on proliferation and survival of primary ectopic human endometriotic stromal cells (ESCs) and the T HESC cell line. Prospective laboratory study. University hospital. 22 women with endometriosis (aged 34.8+/-5.7 years) undergoing therapeutic laparoscopy. Eutopic (n=10) and ectopic (n=22) endometrial tissues were collected from women who underwent therapeutic laparoscopic surgery for endometriosis (stage III/IV). Expression of GHRH, GHRH receptor (GHRH-R) and GHRH-R splice variant (SV) 1 mRNA was determined by reverse-transcription polymerase chain reaction (RT-PCR). The ESC proliferation was assessed by 5-bromo-2-deoxyuridine incorporation, cell survival by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide (MTT) and Trypan blue assay. The T HESC survival was evaluated by MTT, cyclic adenosine monophosphate (cAMP) levels by ELISA, extracellular signal-regulated kinases 1 and 2 (ERK1/2) phosphorylation by Western blot, and insulin-like growth factor (IGF)-2 mRNA by real-time PCR. The ESCs and T HESCs, but not normal endometrial tissues, expressed GHRH-R mRNA; SV1 mRNA was determined in normal endometrial tissues, ESCs, and T HESCs; GHRH mRNAwas found in T HESCs; JV-1-36 inhibited ESC proliferation and ESC and T HESC survival. In T HESCs, JV-1-36 reduced cAMP production and ERK1/2 phosphorylation but had no effect on IGF-2 mRNA expression. The GHRH antagonist JV-1-36 inhibits endometriotic cell proliferation and survival, suggesting that GHRH antagonist may represent promising tools for treatment of endometriosis. Copyright (c) 2010 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  13. Radioimmunological and clinical studies with luteinizing hormone releasing hormone (LRH)

    Dahlen, H.G.

    1986-01-01

    Radioimmunoassay for Luteinizing Hormone Releasing Hormone (LRH) has been established, tested and applied. Optimal conditions for the performance with regards to incubation time, incubation temperature, concentration of antiserum and radiolabelled LRH have been established. The specificity of the LRH immunoassay was investigated. Problems with direct measurement of LRH in plasmas of radioimmunoassay are encountered. The LRH distribution in various tissues of the rat are investigated. By means of a system for continuous monitoring of LH and FSH in women the lowest effective dose of LRH causing a significant release of LH and FSH could be established. (Auth.)

  14. Hypothalamic growth hormone releasing factor deficiency following cranial irradiation

    Ahmed, S.R.; Shalet, S.M.

    1984-01-01

    The effect of synthetic human pancreatic tumour GH releasing factor (hp GRF1-44) on GH release has been studied in 10 patients with radiation-induced GH deficiency and four normal subjects. All 10 patients showed subnormal GH responses to both an ITT (median peak GH 3.2 mU/1) and to arginine stimulation (median peak GH 2.9 mU/1), although the remainder of pituitary function was intact. Following an acute intravenous bolus (100 μg) of hp GRF1-44, there was no GH response in two patients and a subnormal but definite GH response in a further four. The remaining four patients showed a significant GH response (median peak GH level 29 mU/1; range 22-57 mU/1) to hp GRF1-44, similar in magnitude and timing to that seen in th four normals. This strongly suggests that in these four subjects, the discrepancy in GH responses to hp GRF1-44, ITT and to arginine was a result of radiation-induced hypothalamic damage leading to a deficiency of endogenous GRF. The availability of synthetic hp GRF capable of stimulating GH secretion means that the distinction between hypothalamic and pituitary causes of GH deficiency will be of considerable therapeutic importance in the future. (author)

  15. contribution of growth hormone-releasing hormone and

    The strategy used was to stimulate GH secretion in 8 young ... treatment with two oral doses of 50 mg atenolol (to inhibit .... had normal baseline thyroid-stimulating hormone (TSH) ..... production rate of 14% per decade has been documented.'".

  16. contribution of growth hormone-releasing hormone and ...

    and have competed with integrated PHC. ... the horizontal and vertical fibres into a sustainable web. ... The Impact of the Expanded Program 011 Immunizalio11 and the Polio ... Endocrine-Diabetes Unit, Department of Medicine, University of Cape Town ... thes~ elderly subjects by means of GHRH priming, and the failure of ...

  17. Highly potent metallopeptide analogues of luteinizing hormone-releasing hormone

    Bajusz, S.; Janaky, T.; Csernus, V.J.; Bokser, L.; Fekete, M.; Srkalovic, G.; Redding, T.W.; Schally, A.V.

    1989-01-01

    Metal complexes related to the cytotoxic complexes cisplatin [cis-diamminedichloroplatinum(II)] and transbis(salicylaldoximato)copper(II) were incorporated into suitably modified luteinizing hormone-releasing hormone (LH-RH) analogues containing D-lysine at position 6. Some of the metallopeptides thus obtained proved to be highly active LH-RH agonists or antagonists. Most metallopeptide analogues of LH-RH showed high affinities for the membrane receptors of rat pituitary and human breast cancer cells. Some of these metallopeptides had cytotoxic activity against human breast cancer and prostate cancer and prostate cancer cell lines in vitro. Such cytostatic metallopeptides could be envisioned as targeted chemotherapeutic agents in cancers that contain receptors for LH-RH-like peptides

  18. Highly potent metallopeptide analogues of luteinizing hormone-releasing hormone.

    Bajusz, S; Janaky, T; Csernus, V J; Bokser, L; Fekete, M; Srkalovic, G; Redding, T W; Schally, A V

    1989-08-01

    Metal complexes related to the cytotoxic complexes cisplatin [cis-diamminedichloroplatinum(II)] and transbis(salicylaldoximato)copper(II) were incorporated into suitably modified luteinizing hormone-releasing hormone (LH-RH) analogues containing D-lysine at position 6. Some of the metallopeptides thus obtained proved to be highly active LH-RH agonists or antagonists. For instance, SB-40, a PtCl2-containing metallopeptide in which platinum is coordinated to an N epsilon-(DL-2,3-diaminopropionyl)-D-lysine residue [D-Lys(DL-A2pr] at position 6, showed 50 times higher LH-releasing potency than the native hormone. SB-95, [Ac-D-Nal(2)1,D-Phe(pCl)2, D-Pal(3)2, Arg5,D-Lys[DL-A2pr(Sal2Cu)]6,D-Ala10]LH-RH, where Nal(2) is 3-(2-naphthyl)alanine, Pal(3) is 3-(3-pyridyl)alanine, and copper(II) is coordinated to the salicylideneimino moieties resulting from condensation of salicylaldehyde with D-Lys(DL-A2pr)6, caused 100% inhibition of ovulation at a dose of 3 micrograms in rats. Most metallopeptide analogues of LH-RH showed high affinities for the membrane receptors of rat pituitary and human breast cancer cells. Some of these metallopeptides had cytotoxic activity against human breast cancer and prostate cancer cell lines in vitro (this will be the subject of a separate paper on cytotoxicity evaluation). Such cytostatic metallopeptides could be envisioned as targeted chemotherapeutic agents in cancers that contain receptors for LH-RH-like peptides.

  19. Biosynthesis and the conjugation of magnetite nanoparticles with luteinizing hormone releasing hormone (LHRH)

    Obayemi, J.D. [Department of Materials Science and Engineering, African University of Science and Technology (AUST) Abuja, Federal Capital Territory (Nigeria); Department of Materials Science and Engineering, Kwara State University, Malete, Kwara State (Nigeria); Dozie-Nwachukwu, S. [Department of Materials Science and Engineering, African University of Science and Technology (AUST) Abuja, Federal Capital Territory (Nigeria); Sheda Science and Technology Complex (SHESTCO) Abuja, Federal Capital Territory (Nigeria); Danyuo, Y. [Department of Materials Science and Engineering, African University of Science and Technology (AUST) Abuja, Federal Capital Territory (Nigeria); Department of Electronics and Electricals Engineering, Nigerian Turkish Nile University, Abuja (Nigeria); Odusanya, O.S. [Department of Materials Science and Engineering, African University of Science and Technology (AUST) Abuja, Federal Capital Territory (Nigeria); Sheda Science and Technology Complex (SHESTCO) Abuja, Federal Capital Territory (Nigeria); Anuku, N. [Department of Chemistry, Bronx Community College, New York, NY 10453 (United States); Princeton Institute of Science and Technology of Materials (PRISM), Princeton, NJ 08544 (United States); Malatesta, K. [Princeton Institute of Science and Technology of Materials (PRISM), Princeton, NJ 08544 (United States); Department of Mechanical and Aerospace Engineering, Princeton University, NJ 08544 (United States); Soboyejo, W.O., E-mail: soboyejo@princeton.edu [Department of Materials Science and Engineering, African University of Science and Technology (AUST) Abuja, Federal Capital Territory (Nigeria); Princeton Institute of Science and Technology of Materials (PRISM), Princeton, NJ 08544 (United States); Department of Mechanical and Aerospace Engineering, Princeton University, NJ 08544 (United States)

    2015-01-01

    This paper presents the results of an experimental study of the biosynthesis of magnetite nanoparticles (BMNPs) with particle sizes between 10 nm and 60 nm. The biocompatible magnetic nanoparticles are produced from Magnetospirillum magneticum (M.M.) bacteria that respond to magnetic fields. M.M. bacteria were cultured and used to synthesize magnetite nanoparticles. This was done in an enriched magnetic spirillum growth medium (EMSGM) at different pH levels. The nanoparticle concentrations were characterized with UV–Visible (UV–Vis) spectroscopy, while the particle shapes were elucidated via transmission electron microscopy (TEM). The structure of the particles was studied using X-ray diffraction (XRD), while the hydrodynamic radii, particle size distributions and polydispersity of the nanoparticles were characterized using dynamic light scattering (DLS). Carbodiimide reduction was also used to functionalize the BMNPs with a molecular recognition unit (luteinizing hormone releasing hormone, LHRH) that attaches specifically to receptors that are over-expressed on the surfaces of most breast cancer cell types. The resulting nanoparticles were examined using Fourier Transform Infrared (FTIR) spectroscopy and quantitative image analysis. The implications of the results are then discussed for the potential development of magnetic nanoparticles for the specific targeting and treatment of breast cancer. - Highlights: • Biosynthesis of MNPs with clinically relevant sizes between 10 and 60 nm. • New insights into the effects of pH and processing time on nanoparticle shapes and sizes. • Successful conjugation of biosynthesized magnetite nanoparticles to LHRH ligands. • Conjugated BMNPs that are monodispersed with potential biomedical relevance. • Magnetic properties of biosynthesized MNPs suggest potential for MRI enhancement.

  20. Biosynthesis and the conjugation of magnetite nanoparticles with luteinizing hormone releasing hormone (LHRH)

    Obayemi, J.D.; Dozie-Nwachukwu, S.; Danyuo, Y.; Odusanya, O.S.; Anuku, N.; Malatesta, K.; Soboyejo, W.O.

    2015-01-01

    This paper presents the results of an experimental study of the biosynthesis of magnetite nanoparticles (BMNPs) with particle sizes between 10 nm and 60 nm. The biocompatible magnetic nanoparticles are produced from Magnetospirillum magneticum (M.M.) bacteria that respond to magnetic fields. M.M. bacteria were cultured and used to synthesize magnetite nanoparticles. This was done in an enriched magnetic spirillum growth medium (EMSGM) at different pH levels. The nanoparticle concentrations were characterized with UV–Visible (UV–Vis) spectroscopy, while the particle shapes were elucidated via transmission electron microscopy (TEM). The structure of the particles was studied using X-ray diffraction (XRD), while the hydrodynamic radii, particle size distributions and polydispersity of the nanoparticles were characterized using dynamic light scattering (DLS). Carbodiimide reduction was also used to functionalize the BMNPs with a molecular recognition unit (luteinizing hormone releasing hormone, LHRH) that attaches specifically to receptors that are over-expressed on the surfaces of most breast cancer cell types. The resulting nanoparticles were examined using Fourier Transform Infrared (FTIR) spectroscopy and quantitative image analysis. The implications of the results are then discussed for the potential development of magnetic nanoparticles for the specific targeting and treatment of breast cancer. - Highlights: • Biosynthesis of MNPs with clinically relevant sizes between 10 and 60 nm. • New insights into the effects of pH and processing time on nanoparticle shapes and sizes. • Successful conjugation of biosynthesized magnetite nanoparticles to LHRH ligands. • Conjugated BMNPs that are monodispersed with potential biomedical relevance. • Magnetic properties of biosynthesized MNPs suggest potential for MRI enhancement

  1. Ghrelin stimulates growth hormone release from the pituitary via hypothalamic growth hormone-releasing hormone neurons in the cichlid, Oreochromis niloticus

    Ghrelin, a gastric peptide, is implicated in a multiplicity of biological functions, including energy homeostasis and reproduction. Neuronal systems that are involved in energy homeostasis as well as reproduction traverse the hypothalamus, however, the mechanism by which they control energy homeosta...

  2. Nervus terminalis, olfactory nerve, and optic nerve representation of luteinizing hormone-releasing hormone in primates.

    Witkin, J W

    1987-01-01

    The luteinizing hormone-releasing hormone (LHRH) system was examined immunocytochemically in olfactory bulbs of adult monkeys, including two New World species (squirrel monkey, Saimiri sciureus and owl monkey, Aotus trivirgatus) and one Old World species (cynomolgus macaque, Macaca fasciculata), and in the brain and nasal region of a fetal rhesus macaque Macaca mulatta. LHRH neurons and fibers were found sparsely distributed in the olfactory bulbs in all adult monkeys. There was more LHRH in the accessory olfactory bulb (which is absent in Old World monkeys). In the fetal macaque there was a rich distribution of LHRH neurons and fibers along the pathway of the nervus terminalis, anterior and ventral to the olfactory bulb, and in the nasal septum, with fibers branching into the olfactory epithelium. In addition, there were LHRH neurons and fibers in the optic nerve.

  3. Highly potent antagonists of luteinizing hormone-releasing hormone free of edematogenic effects.

    Bajusz, S; Kovacs, M; Gazdag, M; Bokser, L; Karashima, T; Csernus, V J; Janaky, T; Guoth, J; Schally, A V

    1988-03-01

    To eliminate the undesirable edematogenic effect of the luteinizing hormone-releasing hormone (LH-RH) antagonists containing basic D amino acids at position 6, exemplified by [Ac-D-Phe(pCl)1,2,D-Trp3,D-Arg6,D-Ala10]LH-RH [Phe(pCl) indicates 4-chlorophenylalanine], analogs with D-ureidoalkyl amino acids such as D-citrulline (D-Cit) or D-homocitrulline (D-Hci) at position 6 were synthesized and tested in several systems in vitro and in vivo. HPLC analysis revealed that the overall hydrophobicity of the D-Cit/D-Hci6 analogs was similar to that of the basic D-Arg6 antagonists. In vitro, most of the analogs completely inhibited LH-RH-mediated luteinizing hormone release in perfused rat pituitary cell systems at an antagonist to LH-RH molar ratio of 5:1. In vivo, the most active peptides, [Ac-D-Nal(2)1,D-Phe(pCl)2,D-Trp3,D-Cit6,D-Ala10]LH-RH [Nal(2) indicates 3-(2-naphthyl)alanine] and its D-Hci6 analog, caused 100% inhibition of ovulation in cycling rats in doses of 3 micrograms and suppressed the luteinizing hormone level in ovariectomized female rats for 47 hr when administered at doses of 25 micrograms. Characteristically, these peptides did not exert any edematogenic effects even at 1.5 mg/kg. These properties of the D-Cit/D-Hci6 antagonists may make them useful clinically.

  4. Exaggerated gonadotropin response to luteinizing hormone-releasing hormone in amenorrheic runners.

    Yahiro, J; Glass, A R; Fears, W B; Ferguson, E W; Vigersky, R A

    1987-03-01

    Most studies of exercise-induced amenorrhea have compared amenorrheic athletes (usually runners) with sedentary control subjects. Such comparisons will identify hormonal changes that develop as a result of exercise training but cannot determine which of these changes play a role in causing amenorrhea. To obviate this problem, we assessed reproductive hormone status in a group of five amenorrheic runners and compared them to a group of six eumenorrheic runners matched for body fatness, training intensity, and exercise performance. Compared to the eumenorrheic runners, the amenorrheic runners had lower serum estradiol concentrations, similar basal serum luteinizing hormone and follicle-stimulating hormone concentrations, and exaggerated responses of serum gonadotropins after administration of luteinizing hormone-releasing hormone (100 micrograms intravenous bolus). Serum prolactin levels, both basally and after thyrotropin-releasing hormone administration (500 micrograms intravenous bolus) or treadmill exercise, was similar in the two groups, as were serum thyroid function tests (including thyrotropin response to thyrotropin-releasing hormone). Changes in serum cortisol levels after short-term treadmill exercise were similar in both groups, and serum testosterone levels increased after exercise only in the eumenorrheic group. In neither group did such exercise change serum luteinizing hormone, follicle-stimulating hormone, or thyrotropin levels. We concluded that exercise-induced amenorrhea is not solely related to the development of increased prolactin output after exercise training. The exaggerated gonadotropin response to luteinizing hormone-releasing hormone seen in amenorrheic runners in comparison with matched eumenorrheic runners is consistent with a hypothalamic etiology for the menstrual dysfunction, analogous to that previously described in "stress-induced" or "psychogenic" amenorrhea.

  5. Lack of stimulation of 24-hour growth hormone release by hypocaloric diet in obesity

    Rasmussen, M H; Juul, A; Kjems, L L

    1995-01-01

    . This suggests a reversible defect in GH release, rather than a persistent preexisting disorder. It is hypothesized that enhanced bioavailability of IGF-I, acting in concert with elevated proinsulin and insulin levels, may account for the lack of stimulation of 24-hr GH release by the hypocaloric diet in obese...... subjects. We conclude that the increase in 24-h spontaneous GH release and IGFBP-1 levels observed in normal subjects during the last 24 h of a 96-h VLCD is abolished in obese subjects. The lack of short term hypocaloric stimulation of spontaneous GH release may promote the retention of body fat...

  6. Growth hormone-releasing factor induces c-fos expression in cultured primary pituitary cells

    Billestrup, Nils; Mitchell, R L; Vale, W

    1987-01-01

    GH-releasing factor (GRF) and somatostatin regulates the secretion and biosynthesis of GH as well as the proliferation of GH-producing cells. In order to further characterize the mitogenic effect of GRF, we studied the expression of the proto-oncogene c-fos in primary pituitary cells. Maximal...... induction of c-fos mRNA was observed 20-60 min after stimulation with 5 nM GRF, returning to basal levels after 2 h. Somatostatin-14 (5 nM) partially inhibited the GRF induced c-fos expression. Forskolin and phorbol 12, 13 dibutyrate induced c-fos gene in cultured primary pituitary cells with similar...

  7. Pituitary adenomas in mice transgenic for growth hormone-releasing hormone

    Asa, S L; Kovacs, K; Stefaneanu, L

    1992-01-01

    It has been shown that mice transgenic for human GH-releasing hormone (GRH) develop hyperplasia of pituitary somatotrophs, lactotrophs, and mammosomatotrophs, cells capable of producing both GH and PRL, by 8 months of age. We now report that GRH transgenic mice 10-24 months of age develop pituitary...... adenomas, which we characterized by histology, immunohistochemistry, in situ hybridization, and electron microscopy. Of 13 animals examined, all developed GH-immunoreactive neoplasms that had diffuse positivity for GH mRNA by in situ hybridization. Eleven also contained PRL immunoreactivity; in situ...

  8. Adenohypophysial changes in mice transgenic for human growth hormone-releasing factor

    Stefaneanu, L; Kovacs, K; Horvath, E

    1989-01-01

    The effect of protracted GH-releasing factor (GRF) stimulation on adenohypophysial morphology was investigated in six mice transgenic for human GRF (hGRF). All animals had significantly higher plasma levels of GH and GRF and greater body weights than controls. Eight-month-old mice were killed...... of their ultrastructural features, contained secretory granules heavily labeled for GH by immunogold technique; PRL labeling varied from cell to cell, with the predominance of a weak immunostaining and was colocalized with GH in secretory granules. These results indicate that chronic exposure to GRF excess leads...

  9. Luteinizing hormone-releasing hormone analogue (Buserelin) treatment for central precocious puberty: a multi-centre trial.

    Werther, G A; Warne, G L; Ennis, G; Gold, H; Silink, M; Cowell, C T; Quigley, C; Howard, N; Antony, G; Byrne, G C

    1990-02-01

    A multi-centre open trial of Buserelin, a luteinizing hormone-releasing hormone (LHRH) analogue, was conducted in 13 children with central precocious puberty. Eleven children (eight girls and three boys), aged 3.4-10.2 years at commencement, completed the required 12 month period of treatment. Initially all patients received the drug by intranasal spray in a dose of 1200 micrograms/day, but by the end of the 12 month period two were having daily subcutaneous injections and three were receiving an increased dose intranasally. The first month of treatment was associated in one boy with increased aggression and masturbation, and in the girls with an increase in the prevalence of vaginal bleeding. Thereafter, however, both behavioural abnormalities and menstruation were suppressed. Median bone age increased significantly during the study, but without any significant change in the ratio of height age to bone age. The median predicted adult height for the group therefore did not alter significantly over the twelve months of the study. Buserelin treatment caused a reduction in the peak luteinizing hormone and follicle-stimulating hormone (FSH) responses to LHRH, mostly to prepubertal levels, and also suppressed basal FSH. In the first weeks of treatment, the girls' serum oestradiol levels rose significantly and then fell to prepubertal or early pubertal levels. A similar pattern was seen for serum testosterone levels. Serum somatomedin-C levels, however, showed little fluctuation over the course of the study. Buserelin treatment was safe and well accepted, and offers the promise of improved linear growth potential in precocious puberty.

  10. Short-chain analogs of luteinizing hormone-releasing hormone containing cytotoxic moieties.

    Janáky, T; Juhász, A; Rékási, Z; Serfözö, P; Pinski, J; Bokser, L; Srkalovic, G; Milovanovic, S; Redding, T W; Halmos, G

    1992-11-01

    Five hexapeptide and heptapeptide analogs of luteinizing hormone-releasing hormone (LH-RH) were synthesized for use as carriers for cytotoxic compounds. These short analogs were expected to enhance target selectivity of the antineoplastic agents linked to them. Native LH-RH-(3-9) and LH-RH-(4-9) containing D-lysine and D-ornithine at position 6 were amidated with ethylamine and acylated on the N terminus. The receptor-binding affinity of one hexapeptide carrier AJ-41 (Ac-Ser-Tyr-D-Lys-Leu-Arg-Pro-NH-Et) to human breast cancer cell membranes was similar to that of [D-Trp6]LH-RH. Alkylating nitrogen mustards (melphalan, Ac-melphalan), anthraquinone derivatives including anticancer antibiotic doxorubicin, antimetabolite (methotrexate), and cisplatin-like platinum complex were linked to these peptides through their omega-amino group at position 6. The hybrid molecules showed no LH-RH agonistic activity in vitro and in vivo but had nontypical antagonistic effects on pituitary cells in vitro at the doses tested. These analogs showed a wide range of receptor-binding affinities to rat pituitaries and cell membranes of human breast cancer and rat Dunning prostate cancer. Several of these conjugates exerted some cytotoxic effects on MCF-7 breast cancer cell line.

  11. Synthesis and in vitro anti-cancer evaluation of luteinizing hormone-releasing hormone-conjugated peptide.

    Deng, Xin; Qiu, Qianqian; Ma, Ke; Huang, Wenlong; Qian, Hai

    2015-11-01

    Luteinizing hormone-releasing hormone (LHRH) is a decapeptide hormone released from the hypothalamus and shows high affinity binding to the LHRH receptors. It is reported that several cancer cells also express LHRH receptors such as breast, ovarian, prostatic, bladder and others. In this study, we linked B1, an anti-cancer peptide, to LHRH and its analogs to improve the activity against cancer cells with LHRH receptor. Biological evaluation revealed that TB1, the peptide contains triptorelin sequence, present favorable anti-cancer activity as well as plasma stability. Further investigations disclosed that TB1 trigger apoptosis by activating the mitochondria-cytochrome c-caspase apoptotic pathway, it also exhibited the anti-migratory effect on cancer cells.

  12. Serum Testosterone Levels in Prostate Cancer Patients Undergoing Luteinizing Hormone-Releasing Hormone Agonist Therapy.

    Morote, Juan; Comas, Inma; Planas, Jacques; Maldonado, Xavier; Celma, Ana; Placer, José; Ferrer, Roser; Carles, Joan; Regis, Lucas

    2018-04-01

    Serum testosterone measurement is recommended to assess the efficacy of androgen deprivation therapy (ADT) and to diagnose castration resistance in patients with prostate cancer (PCa). Currently, the accepted castrate level of serum testosterone is 50 ng/dL. Liquid chromatography and tandem mass spectrometry (LC MSMS) is the appropriate method to measure testosterone, especially at low levels. However, worldwide, chemiluminescent assays (CLIAs) are used in clinical laboratories, despite their lack of accuracy and reproducibility, because they are automatable, fast, sensitive, and inexpensive. We compared serum testosterone levels measured using LC MSMS and CLIAs in 126 patients with PCa undergoing luteinizing hormone-releasing hormone (LHRH) agonist therapy. The median serum testosterone level was 14.0 ng/dL (range, 2.0-67.0 ng/dL) with LC MSMS and 31.9 ng/dL (range, 10.0-91.6 ng/dL) with CLIA (P  50 ng/dL in 3 patients (2.4%). These ranges were found in 34 (27%), 72 (57.1%), and 20 (15.9%) patients when testosterone was measured using CLIA (P < .001). The castrate level of serum testosterone using LC MSMS and CLIA was 39.8 ng/dL (95% confidence interval [CI], 37.1-43.4 ng/dL) and 66.5 ng/dL (95% CI, 62.3-71.2 ng/dL), respectively. We found that CLIA overestimated the testosterone levels in PCa patients undergoing LHRH agonist therapy. Thus, the castration level was incorrectly considered inadequate with CLIA in almost 15% of patients. The true castration level of serum testosterone using an appropriate method is < 50 ng/dL. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. Action of luteinizing hormone-releasing hormone in rat ovarian cells: Hormone production and signal transduction

    Wang, Jian.

    1989-01-01

    The present study was conducted to investigate the hypothesis that the breakdown of membrane phosphoinositides may participate in the actions of luteinizing hormone-releasing hormone (LHRH) on hormone production in rat granulosa cells. In cells prelabeled with ({sup 3}H)inositol or ({sup 3}H)arachidonic acid (AA), treatment with LHRH increased the formation of radiolabeled inositol 1,4,5-trisphosphate (IP{sub 3}) and diacylglycerol (DG), and the release of radiolabeled AA. Since IP{sub 3} induces intracellular Ca{sup 2+} mobilization, changes in the cytosolic free calcium ion concentrations ((Ca{sup 2+})i) induced by LHRH were studied in individual cells using fura-2 microspectrofluorimetry. Alterations in (Ca{sup 2+})i induced by LHRH were rapid and transient, and could be completely blocked by a LHRH antagonist. Sustained perifusion of LHRH resulted in a desensitization of the (Ca{sup 2+})i response to LHRH. LHRH treatment accelerated (Ca{sup 2+})i depletion in the cells perifused with Ca{sup 2+} free medium, indicating the involvement of intracellular Ca{sup 2+} pool(s) in (Ca{sup 2+})i changes. The actions of LHRH on the regulation of progesterone (P{sub 4}) and prostaglandin E{sub 2} (PGE{sub 2}) production were also examined. LHRH increased basal P{sub 4} production and attenuated FSH induced P{sub 4} production. Both basal and FSH stimulated PGE{sub 2} formation were increased by LHRH. Since LHRH also increased the formation of DG that stimulates the activity of protein kinase C, an activator of protein kinase C (12-0-tetradecanolyphorbol-13-acetate: TPA) was used with the Ca{sup 2+} ionophore A23187 and melittin (an activator of phospholipase A{sub 2}) to examine the roles of protein kinase C, Ca{sup 2+} and free AA, respectively, in LHRH action.

  14. Steroid hormone release as well as renal water and electrolyte excretion of mice expressing PKB/SGK-resistant GSK3.

    Boini, Krishna M; Bhandaru, Madhuri; Mack, Andreas; Lang, Florian

    2008-09-01

    activity in the regulation of steroid hormone release, renal water and electrolyte excretion and blood pressure control.

  15. Growth hormone stimulation test - series (image)

    The growth hormone (GH) is a protein hormone released from the anterior pituitary gland under the control of the hypothalamus. In children, GH has growth-promoting effects on the body. It stimulates the ...

  16. Lower testosterone levels with luteinizing hormone-releasing hormone agonist therapy than with surgical castration: new insights attained by mass spectrometry

    van der Sluis, Tim M.; Bui, Hong N.; Meuleman, Eric J. H.; Heijboer, Annemieke C.; Hartman, Jeroen F.; van Adrichem, Nick; Boevé, Egbert; de Ronde, Willem; van Moorselaar, R. Jeroen A.; Vis, André N.

    2012-01-01

    Androgen deprivation therapy by bilateral orchiectomy (surgical castration) or luteinizing hormone-releasing hormone agonist therapy (medical castration) is recommended for advanced or metastatic prostate cancer. Both methods aim at reducing serum testosterone concentrations to a castrate level

  17. Hedgehog signaling activation induces stem cell proliferation and hormone release in the adult pituitary gland.

    Pyczek, Joanna; Buslei, Rolf; Schult, David; Hölsken, Annett; Buchfelder, Michael; Heß, Ina; Hahn, Heidi; Uhmann, Anja

    2016-04-25

    Hedgehog (HH) signaling is known to be essential during the embryonal development of the pituitary gland but the knowledge about its role in the adult pituitary and in associated tumors is sparse. In this report we investigated the effect of excess Hh signaling activation in murine pituitary explants and analyzed the HH signaling status of human adenopituitary lobes and a large cohort of pituitary adenomas. Our data show that excess Hh signaling led to increased proliferation of Sox2(+) and Sox9(+) adult pituitary stem cells and to elevated expression levels of adrenocorticotropic hormone (Acth), growth hormone (Gh) and prolactin (Prl) in the adult gland. Inhibition of the pathway by cyclopamine reversed these effects indicating that active Hh signaling positively regulates proliferative processes of adult pituitary stem cells and hormone production in the anterior pituitary. Since hormone producing cells of the adenohypophysis as well as ACTH-, GH- and PRL-immunopositive adenomas express SHH and its target GLI1, we furthermore propose that excess HH signaling is involved in the development/maintenance of hormone-producing pituitary adenomas. These findings advance the understanding of physiological hormone regulation and may open new treatment options for pituitary tumors.

  18. ATP-modulated K+ channels sensitive to antidiabetic sulfonylureas are present in adenohypophysis and are involved in growth hormone release.

    Bernardi, H; De Weille, J R; Epelbaum, J; Mourre, C; Amoroso, S; Slama, A; Fosset, M; Lazdunski, M

    1993-01-01

    The adenohypophysis contains high-affinity binding sites for antidiabetic sulfonylureas that are specific blockers of ATP-sensitive K+ channels. The binding protein has a M(r) of 145,000 +/- 5000. The presence of ATP-sensitive K+ channels (26 pS) has been demonstrated by electrophysiological techniques. Intracellular perfusion of adenohypophysis cells with an ATP-free medium to activate ATP-sensitive K+ channels induces a large hyperpolarization (approximately 30 mV) that is antagonized by an...

  19. The impact of blood glucose levels on stimulated adrenocorticotropin hormone and growth hormone release in healthy subjects

    Jakobsdottir, S.; Twisk, J.W.R.; Drent, M.L.

    2009-01-01

    Objective In studies investigating the influence of glucose levels on the pituitary function the methods used have been variable and mainly focused on the change in function as a reaction to unphysiological low or high blood glucose levels. In the present study the impact of physiological and

  20. Is radiation-induced ovarian failure in rhesus monkeys preventable by luteinizing hormone-releasing hormone agonists?: Preliminary observations

    Ataya, K.; Pydyn, E.; Ramahi-Ataya

    1995-01-01

    With the advent of cancer therapy, increasing numbers of cancer patients are achieving long term survival. Impaired ovarian function after radiation therapy has been reported in several studies. Some investigators have suggested that luteinizing hormone-releasing hormone agonists (LHRHa) can prevent radiation-induced ovarian injury in rodents. Adult female rhesus monkeys were given either vehicle or Leuprolide acetate before, during, and after radiation. Radiation was given in a dose of 200 rads/day for a total of 4000 rads to the ovaries. Frequent serum samples were assayed for estradiol (E 2 ) and FSH. Ovariectomy was performed later. Ovaries were processed and serially sectioned. Follicle count and size distribution were determined. Shortly after radiation started, E 2 dropped to low levels, at which it remained, whereas serum FSH level, which was low before radiation, rose soon after starting radiation. In monkeys treated with a combination of LHRHa and radiation, FSH started rising soon after the LHRHa-loaded minipump was removed (after the end of radiation). Serum E 2 increased after the end of LHRHa treatment in the non-irradiated monkey, but not in the irradiated monkey. Follicle counts were not preserved in the LHRHa-treated monkeys that received radiation. The data demonstrated no protective effect of LHRHa treatment against radiation-induced ovarian injury in this rhesus monkey model. 58 refs., 2 figs., 1 tab

  1. Ontogenesis of neurons producing luteinizing hormone-releasing hormone (LHRH) in the nervus terminalis of the rat.

    Schwanzel-Fukuda, M; Morrell, J I; Pfaff, D W

    1985-08-15

    Immunoreactive luteinizing hormone-releasing hormone (LHRH) was first detected at 15 days of gestation in ganglion cells associated with the peripheral, intracranial, and central parts of the nervus terminalis of the rat. LHRH was not detected in any other structure of the central nervous system at this age. In the 17-day-old fetal rat, 62% of the total LHRH-reactive neuronal population was found in ganglion cells of the nervus terminalis. At this same age, immunoreactive beta-luteinizing hormone (beta-LH) was first seen in gonadotropes of the anterior pituitary gland. At 19 days of gestation, 31% of the total number of LHRH-reactive neurons observed in the rat brain was found in the nervus terminalis, and immunoreactive processes were first seen in the organum vasculosum of the lamina terminalis and in the median eminence. Our data indicate that from 15 to 19 days of gestation the nervus terminalis is a principal source of LHRH in the fetal rat. Presence of the decapeptide in the nervus terminalis prior to appearance of beta-LH in the anterior pituitary suggests a possible role for LHRH in this system on maturation of the gonadotropes and differentiation of the brain-pituitary-gonadal axis.

  2. Menstruation recovery after chemotherapy and luteinizing hormone-releasing hormone agonist plus tamoxifen therapy for premenopausal patients with breast cancer.

    Sakurai, Kenichi; Matsuo, Sadanori; Enomoto, Katsuhisa; Amano, Sadao; Shiono, Motomi

    2011-01-01

    Little is known about the period required for menstruation recovery after long-term luteinizing hormone-releasing hormone (LH-RH) agonist plus tamoxifen therapy following chemotherapy. In this study we investigated the period required for menstruation recovery after the therapy. The subjects comprised 105 premenopausal breast cancer patients who had undergone surgery. All patients were administered an LH-RH agonist for 24 months and tamoxifen for 5 years following the postoperative adjuvant chemotherapy, and the status of menstruation recovery was examined. Menstruation resumed in 16 cases (15.2%) after the last LH-RH agonist treatment session. The mean period from the last LH-RH agonist treatment to the recovery of menstruation was 6.9 months. The rate of menstruation recovery was 35.5% in patients aged 40 years or younger and 8.0% in those aged 41 years or older, and it was significantly higher in those aged 40 years or younger. The period until menstruation recovery tended to be longer in older patients at the end of treatment. This study showed that menstruation resumed after treatment at higher rates in younger patients. However, because it is highly likely that ovarian function will be destroyed by the treatment even in young patients, it is considered necessary to explain the risk to patients and obtain informed consent before introducing this treatment modality.

  3. Decapeptides as effective agonists from L-amino acids biologically equivalent to the luteinizing hormone-releasing hormone

    Folkers, K.; Bowers, C.Y.; Tang, P.L.; Kubota, M.

    1986-01-01

    Apparently, no agonist has been found that is comparable in potency to the luteinizing hormone-releasing hormone (LHRH) for release of LH and follicle-stimulating hormone (FSH) without substitutions with unnatural or D forms of natural amino acids. Of 139 known agonist analogs of LHRH, two were active in the range of 65%. The four LHRHs known to occur in nature involve a total of six amino acids (Tyr, His, Leu, Trp, Arg, Gln) in positions 5, 7, and 8. There are 16 possible peptides with these six amino acids in positions 5, 7, and 8, of which 4 are the known LHRHs, and 2 more were synthesized. The authors have synthesized the 10 new peptides and assayed 11 in vivo and in vitro, and they found not only 1 but a total of 5 that have activity equivalent to or greater than that of LHRH for the release of LH and/or FSH under at least one assay condition. These five are as follows: [His 5 ,Trp 7 ,Gln 8 ]LHRH; [His 5 ,Trp 7 ,Leu 8 ]LHRH; [His 5 ,Trp 7 ]LHRH; [Trp 7 ]LHRH; [His 5 ]LHRH. These structures are a basis for the design of antagonists without Arg 8 toward avoiding histamine release. Complete inhibition of LH and FSH release in vivo may be induced by joint use of Arg 8 and Gln 8 or Leu 8 antagonists. These potent agonists, related to LHRH, may be therapeutically useful in disorders of reproduction, the central nervous system, and for the control of hormone-dependent carcinomas. Radioreceptor assays and radioimmunoassays were utilized

  4. Highly potent analogues of luteinizing hormone-releasing hormone containing D-phenylalanine nitrogen mustard in position 6.

    Bajusz, S; Janaky, T; Csernus, V J; Bokser, L; Fekete, M; Srkalovic, G; Redding, T W; Schally, A V

    1989-08-01

    The nitrogen mustard derivatives of 4-phenylbutyric acid and L-phenylalanine, called chlorambucil (Chl) and melphalan (Mel), respectively, have been incorporated into several peptide hormones, including luteinizing hormone-releasing hormone (LH-RH). The alkylating analogues of LH-RH were prepared by linking Chl, as an N-acyl moiety, to the complete amino acid sequence of agonistic and antagonistic analogues. These compounds, in particular the antagonistic analogues, showed much lower potency than their congeners carrying other acyl groups. To obtain highly potent alkylating analogues of LH-RH, the D enantiomer of Mel was incorporated into position 6 of the native hormone and some of its antagonistic analogues. Of the peptides prepared, [D-Mel6]LH-RH (SB-05) and [Ac-D-Nal(2)1,D-Phe(pCl)2,D-Pal(3)3,Arg5,D-Mel6,D-Ala10++ +]LH-RH [SB-86, where Nal(2) is 3-(2-naphthyl)alanine and Pal(3) is 3-(3-pyridyl)alanine] possessed the expected high agonistic and antagonistic activities, respectively, and also showed high affinities for the membrane receptors of rat pituitary cells, human breast cancer cells, human prostate cancer cells, and rat Dunning R-3327 prostate tumor cells. These two analogues exerted cytotoxic effects on human and rat mammary cancer cells in vitro. Thus these two D-Mel6 analogues seem to be particularly suitable for the study of how alkylating analogues of LH-RH could interfere with intracellular events in certain cancer cells.

  5. Highly potent analogues of luteinizing hormone-releasing hormone containing D-phenylalanine nitrogen mustard in position 6

    Bajusz, S.; Janaky, T.; Csernus, V.J.; Bokser, L.; Fekete, M.; Srkalovic, G.; Redding, T.W.; Schally, A.V.

    1989-01-01

    The nitrogen mustard derivatives of 4-phenylbutyric acid and L-phenylalanine, called chlorambucil (Chl) and melphalan (Mel), respectively, have been incorporated into several peptide hormones, including luteinizing hormone-releasing hormone (LH-RH). The alkylating analogues of LH-RH were prepared by linking Chl, as an N-acyl moiety, to the complete amino acid sequence of agonistic and antagonistic analogues. These compounds, in particular the antagonistic analogues, showed much lower potency than their congeners carrying other acyl groups. To obtain highly potent alkylating analogues of LH-RH, the D enantiomer of Mel was incorporated into position 6 of the native hormone and some of its antagonistic analogues. Of the peptides prepared, [D-Mel 6 ]LH-RH (SB-05) and [Ac-D-Nal(2) 1 ,D-Phe(pCl) 2 ,D-Pal(3) 3 ,Arg 5 ,D-Mel 6 ,D-Ala 10 ]LH-RH [SB-86, where Nal(2) is 3-(2-naphthyl)alanine and Pal(3) is 3-(3-pyridyl)alanine] possessed the expected high agonistic and antagonistic activities, respectively, and also showed high affinities for the membrane receptors of rat pituitary cells, human breast cancer cells, human prostate cancer cells, and rat Dunning R-3327 prostate tumor cells. These two analogues exerted cytotoxic effects on human and rat mammary cancer cells in vitro. Thus these two D-Mel 6 analogues seem to be particularly suitable for the study of how alkylating analogues of LH-RH could interfere with intracellular events in certain cancer cells

  6. In vitro effect of Δ9-tetrahydrocannabinol to stimulate somatostatin release and block that of luteinizing hormone-releasing hormone by suppression of the release of prostaglandin E2

    Rettori, V.; Aguila, M.C.; McCann, S.M.; Gimeno, M.F.; Franchi, A.M.

    1990-01-01

    Previous in vivo studies have shown that Δ 9 -tetrahydrocannabinol (THC), the principal active ingredient in marijuana, can suppress both luteinizing hormone (LH) and growth hormone (GH) secretion after its injection into the third ventricle of conscious male rats. The present studies were deigned to determine the mechanism of these effects. Various doses of THC were incubated with either stalk median eminence fragments (MEs) or mediobasal hypothalamic (MBH) fragments in vitro. Although THC (10 nM) did not alter basal release of LH-releasing hormone (LHRH) from MEs in vitro, it completely blocked the stimulatory action of dopamine or nonrepinephrine on LHRH release. The effective doses to block LHRH release were associated with a blockade of synthesis and release of prostaglandin E 2 (PGE 2 ) from MBH in vitro. In contrast to the suppressive effect of THC on LHRH release, somatostatin release from MEs was enhanced in a dose-related manner with a minimal effective dose of 1 nM. Since PGE 2 suppresses somatostatin release, this enhancement may also be related to the suppressive effect of THC on PGE 2 synthesis and release. The authors speculate that these actions are mediated by the recently discovered THC receptors in the tissue. The results indicate that the suppressive effect of THC on LH release is mediated by a blockade of LHRH release, whereas the suppressive effect of the compound on growth hormone release is mediated, at least in part, by a stimulation of somatostatin release

  7. In vitro effect of. Delta. sup 9 -tetrahydrocannabinol to stimulate somatostatin release and block that of luteinizing hormone-releasing hormone by suppression of the release of prostaglandin E sub 2

    Rettori, V.; Aguila, M.C.; McCann, S.M. (Univ. of Texas Southwestern Medical Center at Dallas (United States)); Gimeno, M.F.; Franchi, A.M. (Centro de Estudios Farmacologicos y de Principios Naturales, Buenos Aires (Argentina))

    1990-12-01

    Previous in vivo studies have shown that {Delta}{sup 9}-tetrahydrocannabinol (THC), the principal active ingredient in marijuana, can suppress both luteinizing hormone (LH) and growth hormone (GH) secretion after its injection into the third ventricle of conscious male rats. The present studies were deigned to determine the mechanism of these effects. Various doses of THC were incubated with either stalk median eminence fragments (MEs) or mediobasal hypothalamic (MBH) fragments in vitro. Although THC (10 nM) did not alter basal release of LH-releasing hormone (LHRH) from MEs in vitro, it completely blocked the stimulatory action of dopamine or nonrepinephrine on LHRH release. The effective doses to block LHRH release were associated with a blockade of synthesis and release of prostaglandin E{sub 2} (PGE{sub 2}) from MBH in vitro. In contrast to the suppressive effect of THC on LHRH release, somatostatin release from MEs was enhanced in a dose-related manner with a minimal effective dose of 1 nM. Since PGE{sub 2} suppresses somatostatin release, this enhancement may also be related to the suppressive effect of THC on PGE{sub 2} synthesis and release. The authors speculate that these actions are mediated by the recently discovered THC receptors in the tissue. The results indicate that the suppressive effect of THC on LH release is mediated by a blockade of LHRH release, whereas the suppressive effect of the compound on growth hormone release is mediated, at least in part, by a stimulation of somatostatin release.

  8. A nonpeptidyl growth hormone secretagogue.

    Smith, R G; Cheng, K; Schoen, W R; Pong, S S; Hickey, G; Jacks, T; Butler, B; Chan, W W; Chaung, L Y; Judith, F

    1993-06-11

    A nonpeptidyl secretagogue for growth hormone of the structure 3-amino-3-methyl-N-(2,3,4,5-tetrahydro-2-oxo-1-([2'-(1H-tetrazol-5 -yl) (1,1'-biphenyl)-4-yl]methyl)-1H-1-benzazepin-3(R)-yl)-butanamid e (L-692,429) has been identified. L-692,429 synergizes with the natural growth hormone secretagogue growth hormone-releasing hormone and acts through an alternative signal transduction pathway. The mechanism of action of L-692,429 and studies with peptidyl and nonpeptidyl antagonists suggest that this molecule is a mimic of the growth hormone-releasing hexapeptide His-D-Trp-Ala-Trp-D-Phe-Lys-NH2 (GHRP-6). L-692,429 is an example of a nonpeptidyl specific secretagogue for growth hormone.

  9. Prolonged inhibition of luteinizing hormone and testosterone levels in male rats with the luteinizing hormone-releasing hormone antagonist SB-75.

    Bokser, L; Bajusz, S; Groot, K; Schally, A V

    1990-09-01

    Inhibitory effects of the potent antagonist of luteinizing hormone-releasing hormone N-Ac-[3-(2-naphthyl)-D-alanine1,4-chloro-D-phenylalanine2,3- (3-pyridyl)-D- alanine3,D-citrulline6,D-alanine10]luteinizing hormone-releasing hormone (SB-75) free of edematogenic effects were investigated in male rats. In a study to determine the effect on luteinizing hormone levels in castrated male rats, SB-75 was injected s.c. in doses of 0.625, 1.25, 2.5, 5.0, and 10 micrograms. Blood samples were taken at different intervals for 48 hr. All doses of SB-75 significantly decreased luteinizing hormone levels for greater than 6 hr (P less than 0.01); this inhibition lasted for greater than 24 hr (P less than 0.01) with a dose of 5.0 micrograms and greater than 48 hr with 10 micrograms (P less than 0.05). Serum testosterone levels were also measured in intact male rats injected with SB-75 in doses of 25, 50, and 100 micrograms. All doses produced a dramatic fall in testosterone to castration levels 6 hr after injection (P less than 0.01); this inhibition of serum testosterone was maintained for greater than 72 hr, but only the 100-micrograms dose could keep testosterone in the castration range for greater than 24 hr (P less than 0.01). In another study using a specific RIA, we obtained the pharmacokinetic release pattern of SB-75 from two sustained delivery formulations of SB-75 pamoate microgranules and examined their effect on serum testosterone. After a single i.m. injection of 20 mg of one batch of microgranules, a large peak corresponding to SB-75 at 45.8 ng/ml was observed, corresponding to the "burst" effect. Levels of the analog decreased to 19.6 ng/ml on day 2, gradually reached a concentration of 4.7 ng/ml on day 7, and kept declining thereafter. Testosterone levels were reduced on day 1 (P less than 0.01) and were maintained at low values for greater than 7 days (P less than 0.05). In rats injected with 10 mg of SB-75 pamoate microgranules of the second batch, SB-75 serum

  10. USE OF MOLECULAR BIOLOGICAL TECHNIQUES TO EVALUATE EFFECT OF ENDOGENOUS HORMONES AND A XENOBIOTIC PESTICIDE ON GROWTH OF SHEEPSHEAD MINNOW

    We have developed a teleost model to screen physiological effects of endocrine disrupting chemicals (EDCs) on somatic growth. Growth is largely controlled by the endocrine system via the growth-hormone releasing hormone (GRF) - growth hormone (GH) - insulin-like growth factor (IG...

  11. alpha-difluoromethylornithine modifies gonadotropin-releasing hormone release and follicle-stimulating hormone secretion in the immature female rat.

    Thyssen, S M; Becú-Villalobos, D; Lacau-Mengido, I M; Libertun, C

    1997-06-01

    Polyamines play an essential role in tissue growth and differentiation, in body weight increment, in brain organization, and in the molecular mechanisms of hormonal action, intracellular signaling, and cell-to-cell communication. In a previous study, inhibition of their synthesis by alpha-difluoromethylornithine (DFMO), a specific and irreversible inhibitor of ornithine decarboxylase, during development in female rats, was followed by prolonged high follicle-stimulating hormone (FSH) serum level and a delayed puberty onset. Those changes were relatively independent of body mass and did not impair posterior fertility. The present work studies the mechanisms and site of action of polyamine participation in FSH secretion during development. DFMO was injected in female rats between Days 1 and 9 on alternate days. At 10 days of age, hypothalami from control and DFMO rats were perifused in vitro, and basal and potassium-induced gonadotropin-releasing hormone (GnRH) release were measured. The response to membrane depolarization was altered in DFMO hypothalami. Increased GnRH release in response to a low K+ concentration was evidenced. Adenohypophyses of the same treated prepubertal rats were perifused in vitro and the response to GnRH pulses was checked. In DFMO-treated rats, higher FSH release was observed, with no changes in LH or PRL secretion. Finally, pituitary GnRH receptor number in adenohypophyseal membranes from treated and control groups was quantified. A significant reduction in specific binding was evident in hypophyses from DFMO-treated rats when compared with binding in the control group. In summary, DFMO treatment in a critical developmental period in the female rat impacts the immature GnRH neuronal network and immature gonadotropes. A delay in maturation is evidenced by a higher sensitivity to secretagogs in both pituitary glands and hypothalamic explants. These events could explain the prolonged high FSH serum levels and delayed puberty onset seen in

  12. Regular Yoga Practice Improves Antioxidant Status, Immune Function, and Stress Hormone Releases in Young Healthy People: A Randomized, Double-Blind, Controlled Pilot Study.

    Lim, Sung-Ah; Cheong, Kwang-Jo

    2015-09-01

    The aim of the present study is to highlight the beneficial effects of yoga practice on bio-parameters, such as oxidative stress, antioxidant components, immune functions, and secretion of stress hormones, in healthy young people. This study was conducted on healthy volunteers recruited from among university students, who were divided into two groups: a control (no yoga intervention, n=13) group and a yoga (n=12) group. Yoga practice was with an instructor for 90 minutes once a week spread over 12 weeks, with recommendations to practice daily at home for 40 minutes with the help of a DVD. The yoga program consisted of yoga body poses (asanas), exercises involving awareness, voluntary regulation of breath (pranayama), and meditational practices. Whole blood samples were collected when the volunteers had fasted for 8 hours at 0 and 12 weeks. The oxidative stress/antioxidant components, immune-related cytokines, and stress hormones were evaluated in serum or plasma. Serum levels of nitric oxide, F2-isoprostane, and lipid peroxide were significantly decreased by yoga practice (pstress and improved antioxidant levels of the body. Moreover, yoga beneficially affected stress hormone releases as well as partially improved immune function.

  13. Protective effects of D-Trp6-luteinising hormone-releasing hormone microcapsules against cyclophosphamide-induced gonadotoxicity in female rats.

    Bokser, L; Szende, B; Schally, A V

    1990-06-01

    The possible protective effect of an agonist of luteinising hormone-releasing hormone (LH-RH) against the ovarian damage caused by cyclophosphamide was investigated in rats. D-Trp6-LH-RH microcapsules were injected once a month for 3 months, in a dose calculated to release 25 micrograms day-1. Control animals received the injection vehicle. Sixty days after the first injection of microcapsules, cyclophosphamide was given at a loading dose of 50 mg kg-1 followed by 5 mg kg-1 day-1 for 30 days, while the treatment with D-Trp6-LH-RH was continued. When the ovaries were examined 3 months and 5 months after discontinuation of treatment, a significant reduction in the total number of follicles (P less than 0.01) was found in non-pretreated animals given cyclophosphamide. This reduction affected mainly follicles larger than 100 microns. An irreversible disintegration and destruction of granulosa cells was also observed in this group. In animals pretreated with D-Trp6-LH-RH, administration of cyclophosphamide caused no reduction in the number and diameter of follicles. Thus, the treatment with D-Trp6-LH-RH microcapsules before and during chemotherapy prevented the ovarian injury inflicted by cyclophosphamide. The suppression of gonadal function by LH-RH analogues could be possibly utilised for the protection of the ovaries against damage caused by cytotoxic drugs.

  14. Effects of ionizing radiation and pretreatment with [D-Leu6,des-Gly10] luteinizing hormone-releasing hormone ethylamide on developing rat ovarian follicles

    Jarrell, J.; YoungLai, E.V.; McMahon, A.; Barr, R.; O'Connell, G.; Belbeck, L.

    1987-01-01

    To assess the effects of a gonadotropin-releasing hormone agonist, [D-Leu6,des-Gly10] luteinizing hormone-releasing hormone ethylamide, in ameliorating the damage caused by ionizing radiation, gonadotropin-releasing hormone agonist was administered to rats from day 22 to 37 of age in doses of 0.1, 0.4, and 1.0 microgram/day or vehicle and the rats were sacrificed on day 44 of age. There were no effects on estradiol, progesterone, luteinizing, or follicle-stimulating hormone, nor an effect on ovarian follicle numbers or development. In separate experiments, rats treated with gonadotropin-releasing hormone agonist in doses of 0.04, 0.1, 0.4, or 1.0 microgram/day were either irradiated or sham irradiated on day 30 and all groups sacrificed on day 44 of age. Irradiation produced a reduction in ovarian weight and an increase in ovarian follicular atresia. Pretreatment with the agonist prevented the reduction in ovarian weight and numbers of primordial and preantral follicles but not healthy or atretic antral follicles. Such putative radioprotection should be tested on actual reproductive performance

  15. SIRT1 Regulates Thyroid-Stimulating Hormone Release by Enhancing PIP5Kgamma Activity through Deacetylation of Specific Lysine Residues in Mammals.

    Sayaka Akieda-Asai

    Full Text Available BACKGROUND: SIRT1, a NAD-dependent deacetylase, has diverse roles in a variety of organs such as regulation of endocrine function and metabolism. However, it remains to be addressed how it regulates hormone release there. METHODOLOGY/PRINCIPAL FINDINGS: Here, we report that SIRT1 is abundantly expressed in pituitary thyrotropes and regulates thyroid hormone secretion. Manipulation of SIRT1 level revealed that SIRT1 positively regulated the exocytosis of TSH-containing granules. Using LC/MS-based interactomics, phosphatidylinositol-4-phosphate 5-kinase (PIP5Kgamma was identified as a SIRT1 binding partner and deacetylation substrate. SIRT1 deacetylated two specific lysine residues (K265/K268 in PIP5Kgamma and enhanced PIP5Kgamma enzyme activity. SIRT1-mediated TSH secretion was abolished by PIP5Kgamma knockdown. SIRT1 knockdown decreased the levels of deacetylated PIP5Kgamma, PI(4,5P(2, and reduced the secretion of TSH from pituitary cells. These results were also observed in SIRT1-knockout mice. CONCLUSIONS/SIGNIFICANCE: Our findings indicated that the control of TSH release by the SIRT1-PIP5Kgamma pathway is important for regulating the metabolism of the whole body.

  16. Enhanced Anti-Tumoral Activity of Methotrexate-Human Serum Albumin Conjugated Nanoparticles by Targeting with Luteinizing Hormone-Releasing Hormone (LHRH) Peptide

    Taheri, Azade; Dinarvand, Rassoul; Atyabi, Fatemeh; Ahadi, Fatemeh; Nouri, Farank Salman; Ghahremani, Mohammad Hossein; Ostad, Seyed Nasser; Borougeni, Atefeh Taheri; Mansoori, Pooria

    2011-01-01

    Active targeting could increase the efficacy of anticancer drugs. Methotrexate-human serum albumin (MTX-HSA) conjugates, functionalized by luteinizing hormone-releasing hormone (LHRH) as targeting moieties, with the aim of specifically targeting the cancer cells, were prepared. Owing to the high expression of LHRH receptors in many cancer cells as compared to normal cells, LHRH was used as the targeting ligand in this study. LHRH was conjugated to MTX-HSA nanoparticles via a cross-linker. Three types of LHRH targeted nanoparticles with a mean particle size between 120–138 nm were prepared. The cytotoxicity of LHRH targeted and non-targeted nanoparticles were determined on the LHRH positive and negative cell lines. The internalization of the targeted and non-targeted nanoparticles in LHRH receptor positive and negative cells was investigated using flow cytometry analysis and fluorescence microscopy. The cytotoxicity of the LHRH targeted nanoparticles on the LHRH receptor positive cells were significantly more than non-targeted nanoparticles. LHRH targeted nanoparticles were also internalized by LHRH receptor positive cells significantly more than non-targeted nanoparticles. There were no significant differences between the uptake of targeted and non-targeted nanoparticles to the LHRH receptor negative cells. The active targeting procedure using LHRH targeted MTX-HSA nanoparticles could increase the anti-tumoral activity of MTX. PMID:21845098

  17. A radioreceptor assay of luteinizing hormone-releasing hormone receptor and characterization of LHRH binding to pituitary receptors in Shao duck

    Yang Peixin; Wu Meiwen; Chen Ziyuan

    2000-01-01

    The properties of Shao duck pituitary luteinizing hormone-releasing hormone (LHRH) receptors were analyzed in pituitary membrane preparation and isolated pituitary cells prepared by enzymatic dispersion with collagenase and trypsin, by using a super-agonist analog of (D-Lys 6 ) LHRH. High binding of 125 I-(D-Lys 6 ) LHRH to 10 6 cultured cells of Shao duck was observed after a 90 minute incubation at 4 degree C, while binding was significantly reduced after a 24h incubation. Binding of the radioligand was a function of tissue concentration of Shao duck pituitary membrane preparation, with a positive correlation over the range of 1-2 pituitary per-tube. Specific binding for 125 I-(D-Lys 6 ) LHRH increased with the increase in the amount of 125 I-(D-Lys 6 ) LHRH. The Scatchard analysis of data revealed a linear relationship between the amount of specific binding and the ratio of specific binding to free 1 '2 5 I(D-Lys 6 )LHRH, indicating a single class of high affinity sites. Equilibrium dissociation constant (Kd) was 0.34 nM in pituitary membrane preparation and 0.43 nM in isolated pituitary cells. Both Kd values were near and the maximum binding capacity (B max ) was great in isolated cells, suggesting no significant loss of the LHRH receptor population caused by the enzymatic procedure employed for cell dispersion in the present study. Addition of 9D-Lys 6 ) LHRH displaced bound 125 I-(D-Lys 6 ) LHRH. These results demonstrated the presence and provided characterization of LHRH receptors in Shao duck pituitary

  18. Electromagnetic field effect or simply stress? Effects of UMTS exposure on hippocampal longterm plasticity in the context of procedure related hormone release.

    Nora Prochnow

    Full Text Available Harmful effects of electromagnetic fields (EMF on cognitive and behavioural features of humans and rodents have been controversially discussed and raised persistent concern about adverse effects of EMF on general brain functions. In the present study we applied radio-frequency (RF signals of the Universal Mobile Telecommunications System (UMTS to full brain exposed male Wistar rats in order to elaborate putative influences on stress hormone release (corticosteron; CORT and adrenocorticotropic hormone; ACTH and on hippocampal derived synaptic long-term plasticity (LTP and depression (LTD as electrophysiological hallmarks for memory storage and memory consolidation. Exposure was computer controlled providing blind conditions. Nominal brain-averaged specific absorption rates (SAR as a measure of applied mass-related dissipated RF power were 0, 2, and 10 W/kg over a period of 120 min. Comparison of cage exposed animals revealed, regardless of EMF exposure, significantly increased CORT and ACTH levels which corresponded with generally decreased field potential slopes and amplitudes in hippocampal LTP and LTD. Animals following SAR exposure of 2 W/kg (averaged over the whole brain of 2.3 g tissue mass did not differ from the sham-exposed group in LTP and LTD experiments. In contrast, a significant reduction in LTP and LTD was observed at the high power rate of SAR (10 W/kg. The results demonstrate that a rate of 2 W/kg displays no adverse impact on LTP and LTD, while 10 W/kg leads to significant effects on the electrophysiological parameters, which can be clearly distinguished from the stress derived background. Our findings suggest that UMTS exposure with SAR in the range of 2 W/kg is not harmful to critical markers for memory storage and memory consolidation, however, an influence of UMTS at high energy absorption rates (10 W/kg cannot be excluded.

  19. In Vitro Fertilization Using Luteinizing Hormone-Releasing Hormone Injections Resulted in Healthy Triplets without Increased Attack Rates in a Hereditary Angioedema Case

    Ceyda Tunakan Dalgıç

    2018-01-01

    Full Text Available Hereditary angioedema due to C1-inhibitor deficiency (C1-INH-HAE is a rare, autosomal dominant disorder. The management of pregnant patients with C1-INH-HAE is a challenge for the physician. Intravenous plasma-derived nanofiltered C1-INH (pdC1INH is the only recommended option throughout pregnancy, postpartum, and breastfeeding period. In order to increase pregnancy rates, physicians use fertilization therapies increasing endogen levels of estrogens. Therefore, these techniques can provoke an increase in the number and severity of edema attacks in C1-INH-HAE. Our patient is a 32-year-old female, diagnosed with C1-INH-HAE type 1 since 2004. She had been taking danazol 50–200 mg/day for 9 years. Due to her pregnancy plans in 2013, danazol was discontinued. PdC1INH was prescribed regularly for prophylactic purpose. Triplet pregnancy occurred by in vitro fertilization using luteinizing hormone-releasing hormone (LHRH injections. In our patient, LHRH injections were done four times without causing any severe attack during in vitro fertilization. Angioedema did not worsen during pregnancy and delivery due to the prophylactic use of intravenous pdC1INH in our patient. According to the attack frequency and severity, there was no difference between the three pregnancy trimesters. To our knowledge, this is the first published case of C1-INH-HAE receiving in vitro fertilization therapies without any angioedema attacks during pregnancy and delivery and eventually having healthy triplets with the prophylactic use of intravenous pdC1INH.

  20. Radioimmunoassay for 6-D-tryptophan analog of luteinizing hormone-releasing hormone: measurement of serum levels after administration of long-acting microcapsule formulations

    Mason-Garcia, M.; Vigh, S.; Comaru-Schally, A.M.; Redding, T.W.; Somogyvari-Vigh, A.; Horvath, J.; Schally, A.V.

    1985-01-01

    A sensitive and specific radioimmunoassay for [6-D-tryptophan]luteinizing hormone-releasing hormone ([D-Trp 6 ]LH-RH) was developed and used for following the rate of liberation of [D-Trp 6 ]LH-RH from a long-acting delivery systems based on a microcapsule formulation. Rabbit antibodies were generated against [D-Trp 6 ]LH-RH conjugated to bovine serum albumin with glutaraldehyde. Crossreactivity with LH-RH was less than 1%; there was no significant cross-reactivity with other peptides. The minimal detectable dose of [D-Trp 6 ]LH-RH was 2 pg per tube. In tra- and interassay coefficients of variation were 8% and 10%, respectively. The radioimmunoassay was suitable for direct determination of [D-Trp 6 ]LH-RH in serum, permitting the study of blood levels of the analog after single injections into normal men and after one-a-month administration of microcapsules to rats. In men, 90 min after subcutaneous injection of 250 μg of the peptide, serum [D-Trp 6 ]LH-RH rose to 6-12 ng/ml. Luteinizing hormone was increased 90 min and 24 hr after the administration of the analog. Several batches of microcapsules were tested in rats and the rate of release of [D-Trp 6 ]LH-RH was followed. The improved batch of microcapsules of [D-Trp 6 ]LH-RH increased serum concentrations of the analog for 30 days or longer after intramuscular injection

  1. Immunocytochemical localization of luteinizing hormone-releasing hormone (LHRH) in the nervus terminalis and brain of the big brown bat, Eptesicus fuscus.

    Oelschläger, H A; Northcutt, R G

    1992-01-15

    Little is known about the immunohistochemistry of the nervous system in bats. This is particularly true of the nervus terminalis, which exerts strong influence on the reproductive system during ontogeny and in the adult. Luteinizing hormone-releasing hormone (LHRH) was visualized immunocytochemically in the nervus terminalis and brain of juvenile and adult big brown bats (Eptesicus fuscus). The peripheral LHRH-immunoreactive (ir) cells and fibers (nervus terminalis) are dispersed along the basal surface of the forebrain from the olfactory bulbs to the prepiriform cortex and the interpeduncular fossa. A concentration of peripheral LHRH-ir perikarya and fibers was found at the caudalmost part of the olfactory bulbs, near the medioventral forebrain sulcus; obviously these cells mediate between the bulbs and the remaining forebrain. Within the central nervous system (CNS), LHRH-ir perikarya and fibers were distributed throughout the olfactory tubercle, diagonal band, preoptic area, suprachiasmatic and supraoptic nuclei, the bed nuclei of stria terminalis and stria medullaris, the anterior lateral and posterior hypothalamus, and the tuber cinereum. The highest concentration of cells was found within the arcuate nucleus. Fibers were most concentrated within the median eminence, infundibular stalk, and the medial habenula. The data obtained suggest that this distribution of LHRH immunoreactivity may be characteristic for microchiropteran (insectivorous) bats. The strong projections of LHRH-containing nuclei in the basal forebrain (including the arcuate nucleus) to the habenula, may indicate close functional contact between these brain areas via feedback loops, which could be important for the processing of thermal and other environmental stimuli correlated with hibernation.

  2. Treatment of idiopathic hypogonadotropic hypogonadism in men with luteinizing hormone-releasing hormone: a comparison of treatment with daily injections and with the pulsatile infusion pump.

    Shargil, A A

    1987-03-01

    Thirty husbands in childless couples, aged 24 to 35 years, were treated with luteinizing hormone-releasing hormone (LH-RH) for idiopathic hypogonadotropic hypogonadism (IHH) of peripubertal (incomplete) type. They were azoospermic or oligospermic, with less than 1.5 X 10(6)/ml nonmotile spermatozoa. The diagnosis of IHH was based on clinical and laboratory features and testicular biopsy specimen study and was further supported by results of stimulation tests and gonadotropin-releasing hormone (GnRH) test. Two treatment modalities were used: subcutaneous injections of 500 micrograms LH-RH twice daily; and perpetual subcutaneous injection, via portable infusion pump, of 25 ng/kg LH-RH, at 90-minute intervals. Two patients required a short second period of pulsatile treatment to cause a second pregnancy of their spouses. The pump proved to yield better results, compared with intermittent injections, in respect to endocrine responses, spermatogenesis, and fertility capacity. Normal levels of luteinizing hormone and follicle-stimulating hormone were reached in 2 to 3 weeks and normal testosterone levels in 8 to 10 weeks from the start of treatment. Sperm counts rose to greater than 60 X 10(6)/ml viable spermatozoa with less than 15% of abnormal forms in 3 to 5 months, and the wives conceived. Of a total of 18 deliveries of healthy infants, 12 offspring were identified genetically with their fathers. Four women were still pregnant at the conclusion of the study. The pump was well tolerated, without special operational problems to the patients. Pulsatile treatment is therefore recommended in the treatment of well-diagnosed and carefully selected cases of incomplete IHH.

  3. Non-invasive treatments of luteinizing hormone-releasing hormone for inducing spermiation in American (Bufo americanus) and Gulf Coast (Bufo valliceps) toads.

    Rowson, Angela D.; Obringer, Amy R.; Roth, Terri L.

    2001-01-01

    As many as 20% of all assessed amphibian species are threatened with extinction, and captive breeding programs are becoming important components of conservation strategies for this taxon. For some species, exogenous hormone administration has been integrated into breeding protocols to improve propagation. However, most treatments are administered by an intraperitoneal injection that can be associated with some risks. The general goal of this study was to identify a non-invasive method of applying luteinizing hormone-releasing hormone (LHRH), which reliably induces sperm release in toads. Specific objectives were to 1) test the spermiation response after topical application of different LHRH doses to the abdominal seat region, 2) evaluate the effects of adding the absorption enhancers dimethyl sulfoxide (DMSO), acetone, and glyceryl monocaprylate (GMC) to the LHRH, 3) assess the spermiation response after oral delivery of LHRH in a mealworm vehicle, and 4) compare sperm characteristics and spermiation responses to treatments in two different toad species. Male American (n = 9) and Gulf Coast (n = 7) toads were rotated systematically through a series of treatments. Urine was collected and evaluated for the presence of sperm at 0, 3, 7, 12, and 24 hours post-treatment. There were no statistical differences in spermiation induction or sperm characteristics between American and Gulf Coast toads after the treatments. Oral administration of 100 &mgr;g LHRH was occasionally successful in inducing spermiation, but results appeared largely unreliable. Ventral dermal application of 100 or 10 &mgr;g LHRH in 40% DMSO were more effective (P Zoo Biol 20:63-74, 2001. Copyright 2001 Wiley-Liss, Inc.

  4. Total Androgen Blockade Versus a Luteinizing Hormone-Releasing Hormone Agonist Alone in Men With High-Risk Prostate Cancer Treated With Radiotherapy

    Nanda, Akash; Chen, M.-H.; Moran, Brian J.; Braccioforte, Michelle H.; Dosoretz, Daniel; Salenius, Sharon; Katin, Michael; Ross, Rudi; D'Amico, Anthony V.

    2010-01-01

    Purpose: To assess whether short-course total androgen blockade vs. a luteinizing hormone-releasing hormone (LHRH) agonist alone affects the risk of prostate cancer-specific mortality (PCSM) in men with localized but high-risk disease treated with radiotherapy. Methods and Materials: The study cohort comprised 628 men with T1-T4, N0, M0 prostate cancer with high-risk disease (prostate-specific antigen level >20 ng/mL, Gleason score ≥8, or clinical category ≥T3) treated with 45 Gy of external beam radiotherapy followed by a brachytherapy boost in addition to receiving a median of 4.3 (interquartile range [IQR], 3.6-6.4) months of hormonal blockade with an LHRH agonist plus an antiandrogen or monotherapy with an LHRH agonist. Fine and Gray's multivariable regression analysis was used to determine whether combination androgen suppression therapy (AST) vs. monotherapy affected the risk of PCSM, adjusting for treatment year, duration of AST, age, and known prognostic factors. Results: After a median follow-up of 4.9 (IQR, 3.5-6.5) years, men receiving combination AST had a lower risk of PCSM than those treated with monotherapy (adjusted hazard ratio [AHR], 0.18; 95% confidence interval [CI], 0.04-0.90; p = 0.04). An increasing prostate-specific antigen level (AHR, 2.70; 95% CI, 1.64-4.45; p < 0.001) and clinical category T3/4 disease (AHR, 29.6; 95% CI, 2.88-303.5; p = 0.004) were also associated with an increased risk of PCSM. Conclusions: In men with localized but high-risk prostate cancer treated with external beam radiotherapy and brachytherapy, short-course AST with an LHRH agonist plus an antiandrogen is associated with a decreased risk of PCSM when compared with monotherapy with an LHRH agonist.

  5. Hypothalamic growth hormone-releasing hormone (GHRH) cell number is increased in human illness, but is not reduced in Prader-Willi syndrome or obesity

    Goldstone, Anthony P.; Unmehopa, Unga A.; Swaab, Dick F.

    2003-01-01

    Acute illness leads to increased GH, but reduced IGF-I secretion, while both are reduced in chronic illness. Prader-Willi syndrome (PWS) is a genetic obesity syndrome, with GH deficiency a feature independent of obesity. Reduced GH secretion may result from decreased hypothalamic release of

  6. Cranial irradiation for cerebral and nasopharyngeal tumours in children: evidence for the production of a hypothalmic defect in growth hormone release

    Blacklay, A.; Grossman, A.; Ross, R.J.M.; Savage, M.O.; Davies, P.S.W.; Plowman, P.N.; Besser, G.M.; Coy, D.H.

    1986-01-01

    A synthetic 29-amino acid analogue of human pancreatic GH-releasing hormone (GHRH(1-29)NH 2 ) has recently been shown to stimulate the release of GH in normal subjects. The authors have studied the GH reponse to GHRH(1-29)NH 2 in nine children irradiated for brain and nasopharyngeal tumours, who were not growing and were deficient in GH as assessed by insulin-induced hypoglycaemia. Serum GH rose in response to GHRH(1-29)NH 2 in all the children, and in five the peak serum GH response was > 20 mu./1. The data suggest that when hypothalamo-pituitary irradiation results in GH deficiency, this is due to a failure of the synthesis or delivery of endogenous GHRH from the hypothalamus to the pituitary cells. It also suggests that it may be possible to treat such children using synthetic GHRH in place of exogenous GH. (author)

  7. Effect of long-term administration of an analog of growth hormone-releasing factor on the GH response in rats.

    Karashima, T; Olsen, D; Schally, A V

    1987-06-22

    The effect of the repeated or continuous administration of an analog of GH releasing factor (GH-RF), D-Tyr-1, D-Ala-2, Nle-27, GH-RF(1-29)-NH2 (DBO-29), on the subsequent response to this peptide was investigated in pentobarbital-anesthetized male rats. A sc administration of this analog induced a greater and more prolonged GH release than doses 10 times larger of GH-RF(1-29). The GH increase after sc injection of 10 micrograms/kg bw of the analog was greater than that induced by iv administration of 2 micrograms/kg bw of GH-RF(1-44). Pretreatment with 10 micrograms/kg bw of the analog did not affect the pituitary response to a strong stimulus (20 micrograms/kg bw) of GH-RF(1-44), 24 h later. Pretreatment with the analog in doses of 10 micrograms/kg bw, sc twice a day, 5 days per week for 4 weeks, significantly diminished the GH release in response to a sc injection of the analog (10 micrograms/kg bw), as compared to vehicle-pretreated controls (P less than 0.01). On the other hand, a continuous sc administration of 0.4 micrograms/h of the analog to intact rats for 7 days did not result in a decrease in GH response to a sc injection of the analog (10 micrograms/kg bw). Since the rats injected repeatedly with the analog for 4 weeks still showed a marked, although somewhat reduced response, analogs of this type may be useful clinically.

  8. Effect of priming injections of luteinizing hormone-releasing hormone on spermiation and ovulation in Gϋnther's Toadlet, Pseudophryne guentheri

    Silla Aimee J

    2011-05-01

    Full Text Available Abstract Background In the majority of vertebrates, gametogenesis and gamete-release depend on the pulsatile secretion of luteinizing hormone-releasing hormone (LHRH from the hypothalamus. Studies attempting to artificially stimulate ovulation and spermiation may benefit from mimicking the naturally episodic secretion of LHRH by administering priming injections of a synthetic analogue (LHRHa. This study investigated the impact of low-dose priming injections of LHRHa on gamete-release in the Australian toadlet Pseudophryne guentheri. Methods Toadlets were administered a single dose of two micrograms per. gram LHRHa without a priming injection (no priming, or preceded by one (one priming or two (two priming injections of 0.4 micrograms per. gram LHRHa. Spermiation responses were evaluated at 3, 7 and 12 hrs post hormone administration (PA, and sperm number and viability were quantified using fluorescent microscopy. Oocyte yields were evaluated by stripping females at 10-11 hrs PA. A sub-sample of twenty eggs per female was then fertilised (with sperm obtained from testis macerates and fertilisation success determined. Results No priming induced the release of the highest number of spermatozoa, with a step-wise decrease in the number of spermatozoa released in the one and two priming treatments respectively. Peak sperm-release occurred at 12 hrs PA for all priming treatments and there was no significant difference in sperm viability. Females in the control treatment failed to release oocytes, while those administered an ovulatory dose without priming exhibited a poor ovulatory response. The remaining two priming treatments (one and two priming successfully induced 100% of females to expel an entire clutch. Oocytes obtained from the no, or two priming treatments all failed to fertilise, however oocytes obtained from the one priming treatment displayed an average fertilisation success of 97%. Conclusion Spermiation was most effectively induced in

  9. Acromegaly caused by a growth hormonereleasing hormone secreting carcinoid tumour of the lung : the effect of octreotide treatment

    De Heide, L. J. M.; Van den Berg, G.; Wolthuis, A.; Van Schelven, W. D.

    2007-01-01

    in acromegaly, the overproduction of growth hormone is usually caused by a pituitary adenoma. We report a 74-year-old woman with acromegaly caused by ectopic overproduction of growth hormone-releasing hormone (GHRH), a rare diagnosis. The GHRH appeared to be produced by a carcinoid tumour of the

  10. Role of fibroblast growth factor 19 in the control of glucose homeostasis

    Schaap, Frank G.

    2012-01-01

    Purpose of review Fibroblast growth factor 19 (FGF19) is a postprandial hormone released from the small intestine. FGF19 improves glucose tolerance when overexpressed in mice with impaired glucose tolerance or diabetes. This review summarizes the recent advances in our understanding of the biology

  11. Orally active growth hormone secretagogues: state of the art and clinical perspectives.

    Ghigo, E; Arvat, E; Camanni, F

    1998-04-01

    Growth hormone secretagogues (GHS) are synthetic, non-natural peptidyl and nonpeptidyl molecules with potent stimulatory effect on somatotrope secretion. They have no structural homology with growth hormone-releasing hormone (GHRH) and act via a specific receptor, which has now been cloned and is present at both the pituitary and hypothalamic level. This evidence strongly suggests the existence of a still unknown natural GHS-like ligand. Several data favour the hypothesis that GHS could counteract somatostatinergic activity at both the pituitary and hypothalamic level and/or, at least partially, via a GHRH-mediated mechanism. However, the possibility that they act via an unknown hypothalamic factor remains open. GH-releasing peptide-6 (GHRP-6) is the first hexapeptide studied extensively in humans. More recently, peptidyl superanalogues GHRP-1, GHRP-2 and hexarelin, and nonpeptidyl mimetics, such as the spiroindoline derivative MK-677, have been synthesized and their effects have been studied in humans. The GH-releasing activity of GHS is marked, dose related and reproducible after intravenous, subcutaneous, intranasal and even oral administration. The effect of GHS is partially desensitized but prolonged, intermittent oral administration increases insulin-like growth factor I (IGF-I) levels. The GH-releasing effect of GHS undergoes age-related variations; it increases from birth to puberty, remains similar in adulthood and decreases with ageing. The effect of GHS on GH release is synergistic with that of GHRH, while it is only partially refractory to inhibitory influences, which nearly abolish the effect of GHRH. GHS maintain their GH-releasing activity in some somatotrope hypersecretory states such as acromegaly, anorexia nervosa, hyperthyroidism and critical illness. The GH response to GHS has been reported clear although reduced in GH deficiency, obesity and hypothyroidism, while it is strongly reduced in patients with pituitary stalk disconnection or Cushing

  12. Effects of short-term glucocorticoid deprivation on growth hormone (GH) response to GH-releasing peptide-6: Studies in normal men and in patients with adrenal insufficiency

    Pinto, Ana Claudia de Assis Rocha [UNIFESP; Dias-da-Silva, Magnus Régios [UNIFESP; Martins, Manoel R. [UNIFESP; Brunner, Elisa [UNIFESP; Lengyel, Ana Maria Judith [UNIFESP

    2000-01-01

    There are no data in the literature about the effects of glucocorticoid deprivation on GH-releasing peptide-g (GHRP-6)-induced GH release. the aims of this study were to evaluate GH responsiveness to GHRP-6 1) after metyrapone administration in normal men, and 2) in patients with chronic hypocortisolism after glucocorticoid withdrawal for 72 h. in normal subjects, metyrapone ingestion did not alter significantly GH responsiveness to GHRP-6 [n = 8; peak, 39.3 +/- 7.1 mu g/L; area under the cur...

  13. Passive immunization of fetal rats with antiserum to luteinizing hormone-releasing hormone (LHRH) or transection of the central roots of the nervus terminalis does not affect rat pups' preference for home nest.

    Schwanzel-Fukuda, M; Pfaff, D W

    1987-01-01

    Luteinizing hormone-releasing hormone (LHRH) is found immunocytochemically in cell bodies and fibers of the nervus terminalis, a cranial nerve which courses from the nasal septum through the cribriform plate of the ethmoid bone (medial to the olfactory and vomeronasal nerves) and enters the forebrain, caudal to the olfactory bulbs. Immunoreactive LHRH is first detected in the nervus terminalis of the fetal rat at 15 days of gestation, preceding its detection by immunocytochemistry in any other area of the brain, including the median eminence, and preceding detection of immunoreactive luteinizing hormone (LH) in the anterior pituitary. During development of the rat fetus, the nervus terminalis is the principal source of LHRH in the nervous system from days 15 through 19 of a 21 day gestation period. We tested the notion that the LHRH system of the nervus terminalis is important for olfactory performance by examining the effects of administration of antisera to LHRH during fetal development (versus saline controls), or medial olfactory peduncle transections, in the neonatal rat, which would sever the central projections of the nervus terminalis (versus lateral peduncle transection, complete transection of the olfactory peduncles and the central nervus terminalis or controls) on preferences of rat pups for home nest. The hypothesis that LHRH is important for this chemosensory response was not confirmed. Neither antisera to LHRH nor medical olfactory peduncle transection disrupted preference for home shavings. Only complete olfactory peduncle transection had a significant effect compared to unoperated and sham-operated controls.

  14. Growth

    John R. Jones; George A. Schier

    1985-01-01

    This chapter considers aspen growth as a process, and discusses some characteristics of the growth and development of trees and stands. For the most part, factors affecting growth are discussed elsewhere, particularly in the GENETICS AND VARIATION chapter and in chapters in PART 11. ECOLOGY. Aspen growth as it relates to wood production is examined in the WOOD RESOURCE...

  15. Parallel studies of His-DTrp-Ala-Trp-DPhe-Lys-NH2 and human pancreatic growth hormone-releasing factor-44-NH2 in rat primary pituitary cell monolayer culture.

    Sartor, O; Bowers, C Y; Chang, D

    1985-03-01

    His-DTrp-Ala-Trp-DPhe-Lys-NH2 (GH-RP-6) is a synthetic hexapeptide that specifically releases GH both in vivo and in vitro in pituitary incubates. In this study, for the first time, GH-RP-6 was studied in primary pituitary cell monolayer culture. Parallel studies were performed with human pancreatic GH-releasing factor-44 (hpGRF-44). Culture conditions optimal for GH-RP-6 were not optimal for hpGRF-44. Both peptides released GH in a dose- and time-dependent manner. In this assay system, the ED50 for GH-RP-6 was 9 nM, and the ED50 for hp-GRF-44 was 1.6 nM. Calcium-blocking agents inhibited the GH responses of both peptides as well as basal GH release. Pretreatment with GH-RP-6 decreased the subsequent response to both GH-RP-6 and hpGRF-44. hpGRF-44 down regulated itself but not GH-RP-6. Rat sera potentiated the GH response of hpGRF-44 but not that of GH-RP-6. GH-RP-6 and hpGRF-44 GH responses were additive. These results suggest that GH-RP-6 and hpGRF-44 stimulate GH release via different somatotroph receptors.

  16. Regulation of hormone release by cultured cells from a thyrotropin-growth hormone-secreting pituitary tumor. Direct inhibiting effects of 3,5,3'-triiodothyronine and dexamethasone on thyrotropin secretion.

    Lamberts, S W; Oosterom, R; Verleun, T; Krenning, E P; Assies, H

    1984-08-01

    The regulation of TSH and GH secretion was investigated in cultured tumor cells prepared from a mixed TSH/GH secreting pituitary tumor. The tumor tissue had been removed transsphenoidally from a patient with hyperthyroidism and inappropriately high serum TSH levels and acromegaly. TSH and GH secretion by cultured cells were stimulated in a parallel way by TRH (300 nM) and LHRH (50 nM), but were unaffected by bromocriptine (10 nM). Exposure of the tumor cells to dexamethasone (0.1 microM) or T3 (50 nM) had differential effects on hormone secretion. GH secretion was greatly stimulated by dexamethasone, but unaffected by T3. TSH secretion was inhibited both by T3 and by dexamethasone. So, T3 and glucocorticoids inhibit TSH release by the human pituitary tumor cells studied at least partly by means of a direct effect.

  17. Características testiculares de touros imunizados com vacina anti-hormônio liberador do hormônio luteinizante Testicular characteristics of bulls immunosterilized with anti-luteinizing hormone-releasing hormone vaccine

    Ricardo Zanella

    2009-10-01

    Full Text Available O objetivo deste trabalho foi avaliar a ação imunoesterilizadora de uma vacina anti-hormônio liberador de hormônio luteinizante (LHRH, composta por ovalbumina-LHRH-7 e tiorredoxina-LHRH-7, em touros mestiços Nelore. Vinte e seis touros, com dois anos de idade, foram distribuídos aleatoriamente em dois grupos de 13 animais. No grupo I, os animais receberam uma dose e dois reforços da vacina nos dias 0, 141, e 287 do experimento. No grupo II, os animais não receberam nenhum tratamento (controle. Para avaliar o efeito da vacina nos touros, foi realizada a mensuração da circunferência escrotal no início do experimento e no dia do abate, 741 dias depois. Por ocasião do abate, também foi coletada uma amostra dos testículos para avaliação histológica. O grupo imunizado apresentou circunferência escrotal ao abate de 22±5,98 cm, menor do que a do grupo controle que foi de 35,6±2,4 cm. Na análise histológica dos animais do grupo imunizado, foi observada degeneração testicular com ausência de espermatozoides em 85% dos animais avaliados, os outros 15% apresentaram redução no número de espermatozoides, em comparação aos animais do grupo controle. A vacina anti-LHRH, com fusão de proteínas, é efetiva na castração imunológica de touros e deve ser considerada como alternativa para utilização na produção bovina extensiva no Brasil.The objective of this study was to evaluate the immunosterilization action of the anti-luteinizing hormone-releasing hormone (LHRH vaccine, composed with ovalbumin-LHRH-7 and thioredoxin-LHRH-7, in Nelore-cross bulls. Twenty-six 2-year old bulls were randomly assigned in two groups of 13 animals each. The animals of group I received a primary and two booster injections of the vaccine on days 0, 141, and 287 of the experiment. In group II, the control group, the bulls did not receive any type of treatment. Scrotal circumference was measured in the beginning of the experiment and at slaughter

  18. Dominant dwarfism in transgenic rats by targeting human growth hormone (GH) expression to hypothalamic GH-releasing factor neurons.

    Flavell, D M; Wells, T; Wells, S E; Carmignac, D F; Thomas, G B; Robinson, I C

    1996-01-01

    Expression of human growth hormone (hGH) was targeted to growth hormone-releasing (GRF) neurons in the hypothalamus of transgenic rats. This induced dominant dwarfism by local feedback inhibition of GRF. One line, bearing a single copy of a GRF-hGH transgene, has been characterized in detail, and has been termed Tgr (for Transgenic growth-retarded). hGH was detected by immunocytochemistry in the brain, restricted to the median eminence of the hypothalamus. Low levels were also detected in the...

  19. Receptors for luteinizing hormone-releasing hormone (LHRH) in Dunning R3327 prostate cancers and rat anterior pituitaries after treatment with a sustained delivery system of LHRH antagonist SB-75.

    Srkalovic, G; Bokser, L; Radulovic, S; Korkut, E; Schally, A V

    1990-12-01

    Membrane receptors for LHRH were evaluated in Dunning R3327 prostate cancers and rat anterior pituitaries. The receptors were characterized both in untreated animals and after in vivo treatment with microcapsules of the agonist D-Trp6-LHRH and a sustained delivery system releasing different doses (23.8, 47.6, 71.4 micrograms/day) of LHRH antagonist [Ac-D-Nal(2)1-D-Phe(4Cl)2-D-Pal(3)3,D-Cit6, D-Ala10]-LHRH (SB-75). The therapy, which lasted 8 weeks, strongly inhibited tumor growth. A group of normal Sprague-Dawley male rats was also treated for 6 weeks with microcapsules of SB-75 releasing 25 micrograms/day. In the Dunning tumors from the control group, ligand [125I, D-Trp6]-LHRH was bound to two classes of binding sites [dissociation constant, class a (Kda) = 1.01 +/- 0.30 x 10(-9) M; Kdb = 1.71 +/- 0.41 x 10(-6) M; maximal binding capacity of receptors, class a (Bmaxa) = 48.66 +/- 22.13 fmol/mg of protein; Bmaxb = 92.10 +/- 29.40 pmol/mg of protein] in both kinetic and equilibrium studies. Treatment with D-Trp6-LHRH produced down-regulation of membrane receptors for LHRH in Dunning tumors. Microcapsules of SB-75 resulted in dose-dependent up-regulation of binding sites for LHRH in Dunning tumors. Analysis of the binding data showed that interaction of labeled D-Trp6-LHRH with binding sites in anterior pituitaries was consistent with the presence of a single class of noncooperative receptors (Kd = 43.75 x 10(-9) M; Bmax = 5.25 pmol/mg membrane proteins). Prolonged treatment with microcapsules of D-Trp6-LHRH reduced both Bmax and Kd. Lower doses of SB-75 (23.8 and 47.6 micrograms/day) produced up-regulation, whereas the highest dose (71.4 micrograms/day) resulted in down-regulation of binding sites for LHRH in rat pituitaries. In normal Sprague-Dawley rats, treatment with microcapsules of SB-75 (25 micrograms/day) for 6 weeks produced a slight increase in the number of available binding sites (Bmax = 2.35 +/- 0.82 pmol/mg membrane protein) and a moderate decrease in

  20. Radioimmunoassay for luteinizing hormone releasing hormone in plasma

    Saito, Shiro; Musa, Kimitaka; Oshima, Ichiyo; Yamamoto, Suzuyo; Funato, Toyohiko

    1975-01-01

    A sensitive and specific double antibody radioimmunoassay has been developed capable of measuring LH-RH in extracted human plasma. Thyrotropin releasing hormone, lysine vasopressin and most of LH-RH analogues did not appear to affect the assay. Hypothalamic extract and some of the LH-RH analogues produced displacement curves which were parallel to the curve obtained with the synthetic LH-RH. Sensitivity of the radioimmunoassay was about 3 pg per assay tube. The coefficient of variation of intraassays was 6.4%, while that of interassays was 9.6%. Exogenous LH-RH could be quantitatively extracted by acidic ethanol when varying amounts of synthetic LH-RH were added to the plasma. Immunoreactivity of LH-RH was preserved in plasma for 2 hrs in the cold but was gradually reduced thereafter. The plasma levels of LH-RH were 20 pg/ml or less in normal adults and not detectable in children. Aged males over 60 yr and postmenopausal women showed a tendency to have higher levels of plasma LH-RH. The plasma LH-RH level was significantly higher in midcycle than in the follicular or luteal stages. The disappearance rate of LH-RH from the circulation after intravenous injection could be represented as half-times of 4-6 min. Between 0.2-0.4% of the injected dose was excreted into urine within 1 hr. These results indicate that the determination of LH-RH might be a useful tool for elucidating hypothalamic-pituitary-gonad interactions. (auth.)

  1. Human anti-luteinizing hormone-releasing hormone antibodies in patients treated with synthetic luteinizing hormone-releasing hormone

    Meakin, J.L.; Keogh, E.J.; Martin, C.E.

    1985-01-01

    One hundred sixty-three patients who were given synthetic LH-RH therapeutically underwent monitoring of serum IgG anti-LH-RH antibodies. Five of the patients showed specific binding to antibodies. Development of anti-LH-RH antibodies was not limited to those patients with a congenital deficiency of LH-RH. Urticarial responses occurred in four patients, only one of whom had IgG antibodies. Patients who had IgG antibodies or an urticarial response underwent monitoring of their serum IgE anti-LH-RH antibodies, but none had a positive binding response. The refractory state which has been reported in patients in whom similar antibodies to LH-RH develop was not invariably observed among these patients

  2. Effects of spaceflight on hypothalamic peptide systems controlling pituitary growth hormone dynamics

    Sawchenko, P. E.; Arias, C.; Krasnov, I.; Grindeland, R. E.; Vale, W.

    1992-01-01

    Possible effects of reduced gravity on central hypophysiotropic systems controlling growth hormone (GH) secretion were investigated in rats flown on Cosmos 1887 and 2044 biosatellites. Immunohistochemical (IHC)staining for the growth hormone-releasing factor (GRF), somatostatin (SS), and other hypothalamic hormones was performed on hypothalami obtained from rats. IHC analysis was complemented by quantitative in situ assessments of mRNAs encoding the precursors for these hormones. Data obtained suggest that exposure to microgravity causes a preferential reduction in GRF peptide and mRNA levels in hypophysiotropic neurons, which may contribute to impared GH secretion in animals subjected to spaceflight. Effects of weightlessness are not mimicked by hindlimb suspension in this system.

  3. Growth hormone and tesamorelin in the management of HIV-associated lipodystrophy

    Bedimo R

    2011-07-01

    Full Text Available Roger BedimoInfectious Disease section, VA North Texas Health Care System, TX, USAAbstract: HIV-infected patients on highly active antiretroviral therapy (HAART develop a complex of body composition changes known, including peripheral fat loss (lipoatrophy and central fat accumulation (lipohypertrophy. These changes may cause significant patient distress, which could in turn interfere with adherence to antiretroviral therapy. Treatment options – including antiretroviral switch, insulin sensitizers, and surgical approaches – have been associated with limited success and potential complications. The observation that low growth hormone levels are associated with central fat accumulation among HIV patients has led to the development of tesamorelin (a growth hormone releasing hormone analog for the management of central fat accumulation. Randomized controlled trials have shown that administration of tesamorelin is safe and effective in reducing central fat accumulation among HIV-infected patients. This effect is transient, however, and its association with improved cardiovascular risk remains unclear.Keywords: HAART, HIV, tesamorelin, lipodystrophy

  4. Growth hormone response to GRF 1-44 in children following cranial irradiation for central nervous system tumors

    Oberfield, S.E.; Kirkland, J.L.; Frantz, A.; Allen, J.C.; Levine, L.S.

    1987-01-01

    The growth hormone (GH) responses to (A) GRF 1-44, 1 microgram/kg i.v., (B) L-dopa and either arginine, insulin, or glucagon, and (C) exercise were evaluated in 10 children (3 girls, 7 boys; ages 10 years to 15 years, 8 months), 2-10.75 years following cranial irradiation for medulloblastoma (8 patients), pineoblastoma (1 patient), and a fourth ventricular ependymoma (1 patient). Nine of the 10 children had abnormal growth rates. All children were euthyroid at the time of the study. The mean 0-60-min peak GH response to GRF (10.06 +/- 2.6 ng/ml) in the patients was less than the mean peak GH response (29 +/- 2.3 ng/ml) in the control children (n = 7). In 6 patients (5 with poor growth rates), a decreased GH response was noted to GRF and all other tests. Of the remaining patients, all with poor growth rates, two patients demonstrated an adequate response to GRF and pharmacologic testing; one patient had a normal GH response to GRF with a low GH response to pharmacologic testing; and one patient had a low response to GRF, despite a normal response to both exercise and pharmacologic testing. The decrease in mean peak GH response to GRF in the patient population confirms that radiation to the hypothalamic-pituitary region produces abnormalities in growth hormone release. Furthermore, in these patients, discordant GH responses to GRF and pharmacologic or physiologic tests can be observed. The abnormality in growth hormone release may result from a hypothalamic dysfunction in GRF release and/or damage to GH secretory pituicytes

  5. The Dwarfs of Sindh: severe growth hormone (GH) deficiency caused by a mutation in the GH-releasing hormone receptor gene.

    Baumann, G; Maheshwari, H

    1997-11-01

    We report the discovery of a cluster of severe familial dwarfism in two villages in the Province of Sindh in Pakistan. Dwarfism is proportionate and occurs in members of a kindred with a high degree of consanguinity. Only the last generation is affected, with the oldest dwarf being 28 years old. The mode of inheritance is autosomal recessive. Phenotype analysis and endocrine testing revealed isolated growth hormone deficiency (GHD) as the reason for growth failure. Linkage analysis for the loci of several candidate genes yielded a high lod score for the growth hormone-releasing hormone receptor (GHRH-R) locus on chromosome 7. Amplification and sequencing of the GHRH-R gene in affected subjects demonstrated an amber nonsense mutation (GAG-->TAG; Glu50-->Stop) in exon 3. The mutation, in its homozygous form, segregated 100% with the dwarf phenotype. It predicts a truncation of the GHRH-R in its extracellular domain, which is likely to result in a severely disabled or non-existent receptor protein. Subjects who are heterozygous for the mutation show mild biochemical abnormalities in the growth hormone-releasing hormone (GHRH)--growth hormone--insulin-like growth factor axis, but have only minimal or no growth retardation. The occurrence of an offspring of two dwarfed parents indicates that the GHRH-R is not necessary for fertility in either sex. We conclude that Sindh dwarfism is caused by an inactivating mutation in the GHRH-R gene, resulting in the inability to transmit a GHRH signal and consequent severe isolated GHD.

  6. Neurofibromin regulates somatic growth through the hypothalamic–pituitary axis

    Hegedus, Balazs; Yeh, Tu-Hsueh; Lee, Da Yong; Emnett, Ryan J.; Li, Jia; Gutmann, David H.

    2008-01-01

    To study the role of the neurofibromatosis-1 (NF1) gene in mammalian brain development, we recently generated mice in which Nf1 gene inactivation occurs in neuroglial progenitor cells using the brain lipid binding protein (BLBP) promoter. We found that Nf1BLBPCKO mice exhibit significantly reduced body weights and anterior pituitary gland sizes. We further demonstrate that the small anterior pituitary size reflects loss of neurofibromin expression in the hypothalamus, leading to reduced growth hormone releasing hormone, pituitary growth hormone (GH) and liver insulin-like growth factor-1 (IGF1) production. Since neurofibromin both negatively regulates Ras activity and positively modulates cAMP levels, we examined the signaling pathway responsible for these abnormalities. While BLBP-mediated expression of an activated Ras molecule did not recapitulate the body weight and hypothalamic/pituitary defects, treatment of Nf1BLBPCKO mice with rolipram to increase cAMP levels resulted in a partial restoration of the body weight phenotype. Furthermore, conditional expression of the Ras regulatory GAP domain of neurofibromin also did not rescue the body weight or Igf1 mRNA defects in Nf1BLBPCKO mice. Collectively, these data demonstrate a critical role for neurofibromin in hypothalamic–pituitary axis function and provide further insights into the short stature and GH deficits seen in children with NF1. PMID:18614544

  7. Arid1b haploinsufficient mice reveal neuropsychiatric phenotypes and reversible causes of growth impairment.

    Celen, Cemre; Chuang, Jen-Chieh; Luo, Xin; Nijem, Nadine; Walker, Angela K; Chen, Fei; Zhang, Shuyuan; Chung, Andrew S; Nguyen, Liem H; Nassour, Ibrahim; Budhipramono, Albert; Sun, Xuxu; Bok, Levinus A; McEntagart, Meriel; Gevers, Evelien F; Birnbaum, Shari G; Eisch, Amelia J; Powell, Craig M; Ge, Woo-Ping; Santen, Gijs We; Chahrour, Maria; Zhu, Hao

    2017-07-11

    Sequencing studies have implicated haploinsufficiency of ARID1B , a SWI/SNF chromatin-remodeling subunit, in short stature (Yu et al., 2015), autism spectrum disorder (O'Roak et al., 2012), intellectual disability (Deciphering Developmental Disorders Study, 2015), and corpus callosum agenesis (Halgren et al., 2012). In addition, ARID1B is the most common cause of Coffin-Siris syndrome, a developmental delay syndrome characterized by some of the above abnormalities (Santen et al., 2012; Tsurusaki et al., 2012; Wieczorek et al., 2013). We generated Arid1b heterozygous mice, which showed social behavior impairment, altered vocalization, anxiety-like behavior, neuroanatomical abnormalities, and growth impairment. In the brain, Arid1b haploinsufficiency resulted in changes in the expression of SWI/SNF-regulated genes implicated in neuropsychiatric disorders. A focus on reversible mechanisms identified Insulin-like growth factor (IGF1) deficiency with inadequate compensation by Growth hormone-releasing hormone (GHRH) and Growth hormone (GH), underappreciated findings in ARID1B patients. Therapeutically, GH supplementation was able to correct growth retardation and muscle weakness. This model functionally validates the involvement of ARID1B in human disorders, and allows mechanistic dissection of neurodevelopmental diseases linked to chromatin-remodeling.

  8. Inhibition of rat pituitary growth hormone (GH) release by subclinical levels of lead

    Camoratto, A.M.; White, L.M.; Lau, Y.S.; Moriarty, C.M.

    1990-01-01

    Lead toxicity has been associated with short stature in children. Since growth hormone is a major regulator of growth, the effects of chronic exposure to subclinical lead levels on pituitary function were assessed. Timed pregnant rats were given 125 ppm lead (as lead nitrate) in their drinking water beginning on day 5 of gestation. After weaning, pups were continued on lead until sacrifice at 7 weeks of age. The average blood lead level at this time was 18.9 ug/dl (range 13.7-27.8). On the day of sacrifice the pituitary was removed, hemisected and incubated with vehicle or 40 nM hGRH (human growth hormone releasing hormone). Pituitaries from chronically lead-treated pups were 64% less responsive to GRH than controls. In contrast, no difference in responsiveness was observed in pituitaries from the dams. The specific binding of GRH was also examined. Control animals showed a dose-dependent displacement of 125I-GRH by unlabeled ligand (10-1000 nM). In the pituitaries of lead-treated pups binding of labeled ligand was markedly reduced by unlabeled GRH (less than 100 nM). Chronic exposure to lead had no effect on serum GH or prolactin levels or on pituitary content of GH. These data suggest that one mechanism by which lead can affect growth is by inhibition of GH release

  9. Lead (Pb) attenuation of plasma growth hormone output

    Berry, W.D.; Moriarty, C.M. [Auburn Univ., AL (United States); Lau, Y.S. [Univ. of Missouri, Kansas City, MO (United States); Edwards, G.L. [Univ. of Georgia, Athens, GA (United States)

    1996-03-08

    Lead (Pb) induced growth retardation may occur through disruption of the hypothalamic-pituitary-growth hormone (GH) axis. Episodic GH secretion and GH response to exogenous growth hormone releasing hormone (GHRH) were measured in rats chronically exposed to Pb. Male rats received lead nitrate (1000 ppm) in their drinking water from 21 through 49 days of age gained less weight than non-Pb treated controls (242{plus_minus}3 g vs 309{plus_minus}8 g, P{le}0.01). Mean blood Pb was 40 {plus_minus} 5 ug/dl in Pb treated rats vs. nondetectable in controls. Total food intake was increased by Pb treatment (340 vs 260 g/rat). Mean plasma GH levels were significantly reduced by Pb treatment (40.21 {plus_minus} 7 vs 71.53 {plus_minus} 11 ng/mlP= 0.025). However, the temporal pattern of episodic GH release was maintained in the Pb-treated rats. This indicates that Pb does not disrupt the timing of GHRH and somatostatin (SS) release from the hypothalamus but may alter the relative levels of GHRH and SS released. Pb treated rats also retained the ability to secrete GH in response to exogenous GHRH. However, response to GHRH tended to be lower in the Pb treated rats. The greatest effect of Pb was seen at the highest dose of GHRH 5 {mu}g/kg GHRH dose (485.6 {plus_minus} 103 vs. 870.2 {plus_minus} 317 ng/ml; P =0.2). This suggests that Pb disrupts GH synthesis, signal transduction, or secretory mechanisms in the somatotrope.

  10. Delayed growth

    ... Slow rate of growth; Retarded growth and development; Growth delay Images Toddler development References Cooke DW, Divall SA, Radovick S. Normal and aberrant growth in children. In: Melmed S, Polonsky KS, Larsen PR, ...

  11. Secretion of Growth Hormone in Response to Muscle Sensory Nerve Stimulation

    Grindeland, Richard E.; Roy, R. R.; Edgerton, V. R.; Gosselink, K. L.; Grossman, E. J.; Sawchenko, P. E.; Wade, Charles E. (Technical Monitor)

    1994-01-01

    Growth hormone (GH) secretion is stimulated by aerobic and resistive exercise and inhibited by exposure to actual or simulated (bedrest, hindlimb suspension) microgravity. Moreover, hypothalamic growth hormone-releasing factor (GRF) and preproGRF mRNA are markedly decreased in spaceflight rats. These observations suggest that reduced sensory input from inactive muscles may contribute to the reduced secretion of GH seen in "0 G". Thus, the aim of this study was to determine the effect of muscle sensory nerve stimulation on secretion of GH. Fed male Wistar rats (304 +/- 23 g) were anesthetized (pentobarbital) and the right peroneal (Pe), tibial (T), and sural (S) nerves were cut. Electrical stimulation of the distal (D) or proximal (P) ends of the nerves was implemented for 15 min. to mimic the EMG activity patterns of ankle extensor muscles of a rat walking 1.5 mph. The rats were bled by cardiac puncture and their anterior pituitaries collected. Pituitary and plasma bioactive (BGH) and immunoactive (IGH) GH were measured by bioassay and RIA.

  12. GHRH, PRP-PACAP and GHRHR Target Sequencing via an Ion Torrent Personal Genome Machine Reveals an Association with Growth in Orange-Spotted Grouper (Epinephelus coioides

    Liang Guo

    2015-11-01

    Full Text Available Growth hormone-releasing hormone (GHRH and the receptor, GHRHR, constitute important components of the hypothalamus-pituitary growth axis and act on the downstream growth hormone (GH. PACAP-related peptide/pituitary adenylate cyclase activating polypeptide (PRP-PACAP is a paralog of GHRH. These genes all play key roles in development and growth patterns. To improve the quality of cultured fish strains, natural genetic variation must be examined and understood. A mixed linear model has been widely used in association mapping, taking the population structures and pairwise kinship patterns into consideration. In this study, a mass cross population of orange-spotted grouper (Epinephelus coioides was examined. These candidate genes were found to harbor low nucleotide diversity (θw from 0.00154 to 0.00388 and linkage disequilibrium levels (delay of 50% within 2 kbp. Association mapping was employed, and two single-nucleotide polymorphisms (KR269823.1:g.475A>C and KR269823.1:g.2143T>C were found to be associated with growth (false discovery rate Q < 0.05, explaining 9.0%–17.0% of the phenotypic variance. The association of KR269823.1:g.2143T>C was also found via haplotype-based association (p < 0.05. The identified associations offer new insights into gene functions, and the associated single-nucleotide polymorphisms (SNPs may be used for breeding purposes.

  13. The dwarf phenotype in GH240B mice, haploinsufficient for the autism candidate gene Neurobeachin, is caused by ectopic expression of recombinant human growth hormone.

    Nuytens, Kim; Tuand, Krizia; Fu, Quili; Stijnen, Pieter; Pruniau, Vincent; Meulemans, Sandra; Vankelecom, Hugo; Creemers, John W M

    2014-01-01

    Two knockout mouse models for the autism candidate gene Neurobeachin (Nbea) have been generated independently. Although both models have similar phenotypes, one striking difference is the dwarf phenotype observed in the heterozygous configuration of the GH240B model that is generated by the serendipitous insertion of a promoterless human growth hormone (hGH) genomic fragment in the Nbea gene. In order to elucidate this discrepancy, the dwarfism present in this Nbea mouse model was investigated in detail. The growth deficiency in Nbea+/- mice coincided with an increased percentage of fat mass and a decrease in bone mineral density. Low but detectable levels of hGH were detected in the pituitary and hypothalamus of Nbea+/- mice but not in liver, hippocampus nor in serum. As a consequence, several members of the mouse growth hormone (mGH) signaling cascade showed altered mRNA levels, including a reduction in growth hormone-releasing hormone mRNA in the hypothalamus. Moreover, somatotrope cells were less numerous in the pituitary of Nbea+/- mice and both contained and secreted significantly less mGH resulting in reduced levels of circulating insulin-like growth factor 1. These findings demonstrate that the random integration of the hGH transgene in this mouse model has not only inactivated Nbea but has also resulted in the tissue-specific expression of hGH causing a negative feedback loop, mGH hyposecretion and dwarfism.

  14. The dwarf phenotype in GH240B mice, haploinsufficient for the autism candidate gene Neurobeachin, is caused by ectopic expression of recombinant human growth hormone.

    Kim Nuytens

    Full Text Available Two knockout mouse models for the autism candidate gene Neurobeachin (Nbea have been generated independently. Although both models have similar phenotypes, one striking difference is the dwarf phenotype observed in the heterozygous configuration of the GH240B model that is generated by the serendipitous insertion of a promoterless human growth hormone (hGH genomic fragment in the Nbea gene. In order to elucidate this discrepancy, the dwarfism present in this Nbea mouse model was investigated in detail. The growth deficiency in Nbea+/- mice coincided with an increased percentage of fat mass and a decrease in bone mineral density. Low but detectable levels of hGH were detected in the pituitary and hypothalamus of Nbea+/- mice but not in liver, hippocampus nor in serum. As a consequence, several members of the mouse growth hormone (mGH signaling cascade showed altered mRNA levels, including a reduction in growth hormone-releasing hormone mRNA in the hypothalamus. Moreover, somatotrope cells were less numerous in the pituitary of Nbea+/- mice and both contained and secreted significantly less mGH resulting in reduced levels of circulating insulin-like growth factor 1. These findings demonstrate that the random integration of the hGH transgene in this mouse model has not only inactivated Nbea but has also resulted in the tissue-specific expression of hGH causing a negative feedback loop, mGH hyposecretion and dwarfism.

  15. Pulsatile luteinising hormone releasing hormone for ovulation induction in subfertility associated with polycystic ovary syndrome

    Bayram, N.; van Wely, M.; Vandekerckhove, P.; Lilford, R.; van der Veen, F.

    2000-01-01

    BACKGROUND: In normal menstrual cycles, gonadotrophin releasing hormone (GnRH) secretion is pulsatile, with intervals of 60-120 minutes in the follicular phase. Treatment with pulsatile GnRH infusion by the intra-venous or subcutaneous route using a portable pump has been used successfully in

  16. The effect of ovarian steroid feedback upon radioimmunoreactive luteinizing hormone releasing hormone in the hypothalamus

    Yanaihara, Takumi; Arai, Kiyoshi; Kanazawa, Motomi; Okinaga, Shoichi; Yanaihara, Noboru

    1975-01-01

    A radioimmunoassay (RIA) method for luteinizing hormone (LH) releasing hormone (RH) utilizing rabbit antiserum against synthetic (Glu 1 )-LH-RH coupled with human serum albumin at the N-terminus, is described. This assay system for LH-RH also cross-reacted with several LH-RH analogues or fragments, but not with pituitary trophic hormones. The assay was performed on the hypothalamic extracts of adult ovariectomized rats and female immature rats which had been treated with estradiol. The FSH and LH levels in the pituitary gland and serum of the same animals were determined by RIA. The radioimmunoreactive LH-RH content of the stalk median eminence markedly increased seven days after ovariectomy. The serum levels and the pituitary contents of FSH and LH of the same rats were also significantly augmented. In immature rats, the hypothalamic content of LH-RH, as measured by RIA, was significantly increased one hour after the injection of estradiol. The FSH and LH levels in the pituitary showed a significant rise after 7 hours. (auth.)

  17. Diacylglycerol acyltransferase-1 (DGAT1 inhibition perturbs postprandial gut hormone release.

    Hua V Lin

    Full Text Available Diacylglycerol acyltransferase-1 (DGAT1 is a potential therapeutic target for treatment of obesity and related metabolic diseases. However, the degree of DGAT1 inhibition required for metabolic benefits is unclear. Here we show that partial DGAT1 deficiency in mice suppressed postprandial triglyceridemia, led to elevations in glucagon-like peptide-1 (GLP-1 and peptide YY (PYY only following meals with very high lipid content, and did not protect from diet-induced obesity. Maximal DGAT1 inhibition led to enhanced GLP-1 and PYY secretion following meals with physiologically relevant lipid content. Finally, combination of DGAT1 inhibition with dipeptidyl-peptidase-4 (DPP-4 inhibition led to further enhancements in active GLP-1 in mice and dogs. The current study suggests that targeting DGAT1 to enhance postprandial gut hormone secretion requires maximal inhibition, and suggests combination with DPP-4i as a potential strategy to develop DGAT1 inhibitors for treatment of metabolic diseases.

  18. Hedgehog signaling activation induces stem cell proliferation and hormone release in the adult pituitary gland

    Joanna Pyczek; Rolf Buslei; David Schult; Annett Hölsken; Michael Buchfelder; Ina Heß; Heidi Hahn; Anja Uhmann

    2016-01-01

    Hedgehog (HH) signaling is known to be essential during the embryonal development of the pituitary gland but the knowledge about its role in the adult pituitary and in associated tumors is sparse. In this report we investigated the effect of excess Hh signaling activation in murine pituitary explants and analyzed the HH signaling status of human adenopituitary lobes and a large cohort of pituitary adenomas. Our data show that excess Hh signaling led to increased proliferation of Sox2(+) and S...

  19. Simultaneous measurement of hormone release and secretagogue binding by individual pituitary cells

    Smith, P.F.; Neill, J.D.

    1987-01-01

    The quantitative relationship between receptor binding and hormone secretion at the single-cell level was investigated in the present study by combining a reverse hemolytic plaque assay for measurement of luteinizing hormone (LH) secretion from individual pituitary cells with an autoradiographic assay of 125 I-labeled gonadontropin-releasing hormone (GnRH) agonist binding to the same cells. In the plaque assay, LH secretion induces complement-mediated lysis of the LH-antibody-coated erythrocytes around the gonadotropes, resulting in areas of lysis (plaques). LH release from individual gonadotropes was quantified by comparing radioimmunoassayable LH release to hemolytic area in similarly treated cohort groups of cells; plaque area was linearly related to the amount of LH secreted. Receptor autoradiography was performed using 125 I-labeled GnRH-A (a superagonist analog of GnRH) both as the ligand and as the stimulant for LH release in the plaque assay. The grains appeared to represent specific and high-affinity receptors for GnRH because (i) no pituitary cells other than gonadotropes bound the labeled ligand and (ii) grain development was progressively inhibited by coincubation with increasing doses of unlabeled GnRH-A. The authors conclude that GnRH receptor number for any individual gonadotrope is a weak determinant of the amount of LH it can secrete; nevertheless, full occupancy of all its GnRH receptors is required for any gonadotrope to reach its full LH-secretory capacity. Apparently the levels of other factors comprising the steps along the secretory pathway determine the secretory capacity of an individual cell

  20. Inhibition of parathyroid hormone release by maitotoxin, a calcium channel activator

    Fitzpatrick, L.A.; Yasumoto, T.; Aurbach, G.D.

    1989-01-01

    Maitotoxin, a toxin derived from a marine dinoflagellate, is a potent activator of voltage-sensitive calcium channels. To further test the hypothesis that inhibition of PTH secretion by calcium is mediated via a calcium channel we studied the effect of maitotoxin on dispersed bovine parathyroid cells. Maitotoxin inhibited PTH release in a dose-dependent fashion, and inhibition was maximal at 1 ng/ml. Chelation of extracellular calcium by EGTA blocked the inhibition of PTH by maitotoxin. Maitotoxin enhanced the effects of the dihydropyridine calcium channel agonist (+)202-791 and increased the rate of radiocalcium uptake in parathyroid cells. Pertussis toxin, which ADP-ribosylates and inactivates a guanine nucleotide regulatory protein that interacts with calcium channels in the parathyroid cell, did not affect the inhibition of PTH secretion by maitotoxin. Maitotoxin, by its action on calcium channels allows entry of extracellular calcium and inhibits PTH release. Our results suggest that calcium channels are involved in the release of PTH. Inhibition of PTH release by maitotoxin is not sensitive to pertussis toxin, suggesting that maitotoxin may act distal to the site interacting with a guanine nucleotide regulatory protein, or maitotoxin could interact with other ions or second messengers to inhibit PTH release

  1. Melatonin improves memory acquisition under stress independent of stress hormone release

    Rimmele, U; Spillmann, M; Bärtschi, C; Wolf, O T; Weber, C S; Ehlert, Ulrike; Wirtz, P H

    2009-01-01

    RATIONALE: Animal studies suggest that the pineal hormone melatonin influences basal stress hormone levels and dampens hormone reactivity to stress. OBJECTIVES: We investigated whether melatonin also has a suppressive effect on stress-induced catecholamine and cortisol release in humans. As stress hormones affect memory processing, we further examined a possible accompanying modulation of memory function. MATERIALS AND METHODS: Fifty healthy young men received a single oral dose of either 3...

  2. Luteinizing hormone-releasing hormone (LHRH) and its analogs for contraception in women: a review.

    Thau, R B

    1984-02-01

    In animals, LHRH agonists have multiple sites of action including the pituitary, the gonads, and the reproductive tract. In humans, the major antifertility action of this class of peptides is believed to be mediated via the pituitary. Studies in women have indicated that potent LHRH agonists can block ovulation when administered once daily. In the volunteers who have used these agents no serious side effects were observed, although some women experienced irregular bleeding or amenorrhea. It is anticipated that formal clinical trials could be conducted in the near future to determine the efficacy of continuous LHRH agonist administration. Early attempts to use an LHRH agonist to produce luteal insufficiency, luteolysis, or interruption of pregnancy have either been unsuccessful or the results are still too preliminary to ascertain whether these approaches warrant further trials. LHRH antagonists are believed to act by inhibiting the action of LHRH on the pituitary. Although some of these peptides are known to be active in women, very large doses have been required. Recently several investigators have produced LHRH antagonists with increased potency. In the near future, it should be possible to determine whether these peptides should be considered as potential contraceptives in men or in women.

  3. Growth Disorders

    ... too little of it may be very short. Treatment with growth hormone can stimulate growth. People can also have too much growth hormone. Usually the cause is a pituitary gland tumor, which is not cancer. Too much growth hormone can cause gigantism in children, where their bones and their body ...

  4. Response to growth hormone treatment and final height after cranial or craniospinal irradiation

    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

  5. Response to growth hormone treatment and final height after cranial or craniospinal irradiation

    Sulmont, V.; Brauner, R.; Fontoura, M.; Rappaport, R. (Hospital des Enfants Malades, Paris (France). Pediatric Endocrinology Unit and INSERM U30)

    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.

  6. Inhibition of growth hormone and prolactin secretion by a serine proteinase inhibitor

    Rappay, G.; Nagy, I.; Makara, G.B.; Horvath, G.; Karteszi, M.; Bacsy, E.; Stark, E.

    1984-01-01

    The action of the tripeptide aldehyde t-butyloxycarbonyl-DPhe-Pro-Arg-H (boc-fPR-H), belonging to a family of serine proteinase inhibitors, on the release of immunoreactive prolactin (iPRL) and growth hormone (iGH) has been studied. In rat anterior pituitary cell cultures and pituitary quarters 1 mM boc-fPR-H inhibited basal iPRL and iGH release. Thyroliberin-induced iPRL release by cultured cells was also markedly inhibited with a concomitant accumulation of intracellular iPRL. During the short- and long-term exposure of cells to boc-fPR-H there were no changes in total cell protein contents and in activities of some lysosomal marker enzymes. The marked inhibition of basal as well as stimulated hormone release in the presence of the enzyme inhibitor might suggest that at least a portion of the hormones is released via a proteolytic enzyme-dependent process

  7. Effects of growth hormone treatment on the pituitary expression of GHRH receptor mRNA in uremic rats.

    Ferrando, Susana; Rodríguez, Julián; Santos, Fernando; Weruaga, Ana; Fernández, Marta; Carbajo, Eduardo; García, Enrique

    2002-09-01

    A decreased ability of pituitary cells to secrete growth hormone (GH) in response to growth hormone releasing hormone (GHRH) stimulation has been shown in young uremic rats. The aim of the current study was to examine the effect of uremia and GH treatment on pituitary GHRH receptor expression. Pituitary GHRH receptor mRNA levels were analyzed by RNase protection assay in young female rats made uremic by subtotal nephrectomy, either untreated (UREM) or treated with 10 IU/kg/day of GH (UREM-GH), and normal renal function animals fed ad libitum (SAL) or pair-fed with the UREM group (SPF). Rats were sacrificed 14 days after the second stage nephrectomy. Renal failure was confirmed by concentrations (X +/- SEM) of serum urea nitrogen (mmol/L) and creatinine (micromol/L) in UREM (20 +/- 1 and 89.4 +/- 4.5) and UREM-GH (16 +/- 1 and 91.4 +/- 6.9) that were much higher (P growth retarded as shown by a daily longitudinal tibia growth rate below (P growth rate acceleration (213 +/- 6 microm/day). GHRH receptor mRNA levels were no different among the SAL (0.43 +/- 0.03), SPF (0.43 +/- 0.08) and UREM (0.44 +/- 0.04) groups, whereas UREM-GH rats had significantly higher values (0.72 +/- 0.07). The status of pituitary GHRH receptor is not modified by nutritional deficit or by severe uremia causing growth retardation. By contrast, the growth promoting effect of GH administration is associated with stimulated GHRH receptor gene expression.

  8. The growth hormone-insulin-like growth factor axis in glycogen storage disease type 1: evidence of different growth patterns and insulin-like growth factor levels in patients with glycogen storage disease type 1a and 1b.

    Melis, Daniela; Pivonello, Rosario; Parenti, Giancarlo; Della Casa, Roberto; Salerno, Mariacarolina; Balivo, Francesca; Piccolo, Pasquale; Di Somma, Carolina; Colao, Annamaria; Andria, Generoso

    2010-04-01

    To investigate the growth hormone (GH)-insulin-like growth factor (IGF) system in patients with glycogen storage disease type 1 (GSD1). This was a prospective, case-control study. Ten patients with GSD1a and 7 patients with GSD1b who were given dietary treatment and 34 sex-, age-, body mass index-, and pubertal stage-matched control subjects entered the study. Auxological parameters were correlated with circulating GH, either at basal or after growth hormone releasing hormone plus arginine test, insulin-like growth factors (IGF-I and IGF-II), and anti-pituitary antibodies (APA). Short stature was detected in 10.0% of patients with GSD1a, 42.9% of patients with GSD1b (P = .02), and none of the control subjects. Serum IGF-I levels were lower in patients with GSD1b (P = .0001). An impaired GH secretion was found in 40% of patients with GSD1a (P = .008), 57.1% of patients with GSD1b (P = .006), and none of the control subjects. Short stature was demonstrated in 3 of 4 patients with GSD1b and GH deficiency. The prevalence of APA was significantly higher in patients with GSD1b than in patients with GSD1a (P = .02) and control subjects (P = .03). The GH response to the provocative test inversely correlated with the presence of APA (P = .003). Compared with levels in control subjects, serum IGF-II and insulin levels were higher in both groups of patients, in whom IGF-II levels directly correlated with height SD scores (P = .003). Patients with GSD1a have an impaired GH secretion associated with reference range serum IGF-I levels and normal stature, whereas in patients with GSD1b, the impaired GH secretion, probably because of the presence of APA, was associated with reduced IGF-I levels and increased prevalence of short stature. The increased IGF-II levels, probably caused by increased insulin levels, in patients with GSD1 are presumably responsible for the improved growth pattern observed in patients receiving strict dietary treatment. Copyright 2010 Mosby, Inc. All

  9. Agenesis of internal carotid artery associated with isolated growth hormone deficiency: a case report and literature review.

    Stagi, Stefano; Traficante, Giovanna; Lapi, Elisabetta; Pantaleo, Marilena; Becciani, Sabrina; Mortilla, Marzia; Seminara, Salvatore; de Martino, Maurizio

    2015-10-19

    Agenesis of the internal carotid artery (ICA) is a rare congenital abnormality, sporadically reported to be associated with a combined congenital hypopituitarism. Nevertheless, only a few cases have been extensively described, and none of these have been characterized by an isolated growth hormone (GH) deficiency. Here, we describe a 17-year old boy referred to our hospital for fatigue, decreased muscle strength and severe headache reported after the cessation of rhGH treatment for a GH deficiency diagnosed at the age of 2 years and 3 months. Magnetic resonance imaging (MRI) showed an adenohypophyseal hypoplasia with a lack of posterior pituitary hyperintensity, whereas MRI angiography indicated the absence of a normal flow void in the left ICA. Endocrinological tests confirmed the GH deficiency (GH peak after growth-hormone-releasing hormone (GHRH) + arginine: 2.42 ng/mL) with a very low IGF-I value (31 ng/mL) and normal function of other pituitary axes. To the best of our knowledge this is the first confirmed case of an isolated GH deficiency in a patient with ICA agenesis. The presence of an isolated pituitary deficit is unlike to be considered only as an effect of hemodynamic mechanism, suggesting a role for genetic factor(s) as a common cause of these two rare birth defects. Further studies could clarify this issue and the underlying mechanisms to better understand the etiopathogenetic characteristics of this disorder.

  10. Nutritional status in the neuroendocrine control of growth hormone secretion: the model of anorexia nervosa.

    Scacchi, Massimo; Pincelli, Angela Ida; Cavagnini, Francesco

    2003-07-01

    Growth hormone (GH) plays a key role not only in the promotion of linear growth but also in the regulation of intermediary metabolism, body composition, and energy expenditure. On the whole, the hormone appears to direct fuel metabolism towards the preferential oxidation of lipids instead of glucose and proteins, and to convey the energy derived from metabolic processes towards the synthesis of proteins. On the other hand, body energy stores and circulating energetic substrates take an important part in the regulation of somatotropin release. Finally, central and peripheral peptides participating in the control of food intake and energy expenditure (neuropeptide Y, leptin, and ghrelin) are also involved in the regulation of GH secretion. Altogether, nutritional status has to be regarded as a major determinant in the regulation of the somatotropin-somatomedin axis in animals and humans. In these latter, overweight is associated with marked impairment of spontaneous and stimulated GH release, while acute dietary restriction and chronic undernutrition induce an amplification of spontaneous secretion together with a clear-cut decrease in insulin-like growth factor I (IGF-I) plasma levels. Thus, over- and undernutrition represent two conditions connoted by GH hypersensitivity and GH resistance, respectively. Anorexia nervosa (AN) is a psychiatric disorder characterized by peculiar changes of the GH-IGF-I axis. In these patients, low circulating IGF-I levels are associated with enhanced GH production rate, highly disordered mode of somatotropin release, and variability of GH responsiveness to different pharmacological challenges. These abnormalities are likely due not only to the lack of negative IGF-I feedback, but also to a primary hypothalamic alteration with increased frequency of growth hormone releasing hormone discharges and decreased somatostatinergic tone. Given the reversal of the above alterations following weight recovery, these abnormalities can be seen as

  11. growth stimulant

    Effects of timing and duration of supplementation of LIVFIT VET ® (growth stimulant) as substitute for fish meal on the growth performance, haematology and clinical enzymes concentration of growing pigs.

  12. Insulin-like growth factors: assay methods and their implications

    Guyda, H.J.; Posner, B.I.; Schiffrin, A.; Rappaport, R.; Postel-Vinay, M.C.; Corvol, M.T.

    1981-01-01

    The insulin-like growth factors (IGF's) are small molecular weight peptides (6-10 x 10 3 daltons) that circulate in blood plasma almost entirely bound to macromolecular carrier proteins. The growth-promoting and insulin-like activities of IGF's can be explained by the observed ability of these peptides to interact with the IGF receptor on the one hand and with the insulin receptor on the other. These observations have led to the establishment of radioreceptor assays (RRA's), competitive protein binding assays (CPBA's), and more recently radioimmunoassays (RIA's) for the IGF's that have different specificities. Because of their ease of performance and sensitivity, the radioligand assays have largely supplanted the biological assays originally utilized to identify and characterize these anabolic peptides. In this report the authors' studies are summarised which utilize a slightly acidic IGF which has been purified on the basis of its insulin-like activity in an insulin RRA and which was termed ILAs. They refer to purified insulin-like peptides that have the properties of a somatomedin by the generic term insulin-like growth factor (IGF). Somatomedin (SM) activity will be utilized to connote that activity in plasma or serum determined by bioassay. The competitive dose-response curves for IGF peptides in the insulin RRA as well as those in the ILAs RRA are presented. A combination of bioassays, RRA and RIA were employed to assess somatomedin activity and IGF peptide levels in a number of clinical circumstances. The correlations are discussed. (Auth.)

  13. Growth references

    Buuren, S. van

    2007-01-01

    A growth reference describes the variation of an anthropometric measurement within a group of individuals. A reference is a tool for grouping and analyzing data and provides a common basis for comparing populations.1 A well known type of reference is the age-conditional growth diagram. The

  14. Growth hormone secretagogue receptor (GHS-R1a) knockout mice exhibit improved spatial memory and deficits in contextual memory.

    Albarran-Zeckler, Rosie G; Brantley, Alicia Faruzzi; Smith, Roy G

    2012-06-15

    Although the hormone ghrelin is best known for its stimulatory effect on appetite and regulation of growth hormone release, it is also reported to have beneficial effects on learning and memory formation in mice. Nevertheless, controversy exists about whether endogenous ghrelin acts on its receptors in extra-hypothalamic areas of the brain. The ghrelin receptor (GHS-R1a) is co-expressed in neurons that express dopamine receptor type-1 (DRD1a) and type-2 (DRD2), and we have shown that a subset of GHS-R1a, which are not occupied by the agonist (apo-GHSR1a), heterodimerize with these two receptors to regulate dopamine signaling in vitro and in vivo. To determine the consequences of ghsr ablation on brain function, congenic ghsr -/- mice on the C57BL6/J background were subjected to a battery of behavioral tests. We show that the ghsr -/- mice exhibit normal balance, movement, coordination, and pain sensation, outperform ghsr +/+ mice in the Morris water maze, but show deficits in contextual fear conditioning. Copyright © 2012 Elsevier B.V. All rights reserved.

  15. Two siblings with isolated GH deficiency due to loss-of-function mutation in the GHRHR gene: successful treatment with growth hormone despite late admission and severe growth retardation.

    Sıklar, Zeynep; Berberoğlu, Merih; Legendre, Maria; Amselem, Serge; Evliyaoğlu, Olcay; Hacıhamdioğlu, Bülent; Savaş Erdeve, Senay; Oçal, Gönül

    2010-01-01

    Patients with growth hormone releasing hormone receptor (GHRHR) mutations exhibit pronounced dwarfism and are phenotypically and biochemically indistinguishable from other forms of isolated growth hormone deficiency (IGHD). We presented here two siblings with clinical findings of IGHD due to a nonsense mutation in the GHRHR gene who reached their target height in spite of late GH treatment. Two female siblings were admitted to our clinic with severe short stature at the age of 13.8 (patient 1) and 14.8 years (patient 2). On admission, height in patient 1 was 107 cm (-8.6 SD) and 117 cm (-6.7 SD) in patient 2. Bone age was delayed in both patients (6 years and 9 years). Clinical and biochemical analyses revealed a diagnosis of complete IGHD (peak GH levels on stimulation test was 0.06 ng/mL in patient 1 and 0.16 ng/mL in patient 2). Patients were given recombinant human GH treatment. Genetic analysis of the GH and GHRHR genes revealed that both patientscarried the GHRHR gene mutation p.Glu72X (c.214 G>T) in exon 3 in homozygous (or hemizygous) state. After seven years of GH treatment, the patients reached a final height appropriate for their target height. Final height was 151 cm (-1.5 SD) in patient 1 and 153 cm (-1.2 SD) in patient 2. In conclusion, genetic analysis is indicated in IGHD patients with severe growth failure and a positive family history. In spite of the very late diagnosis in these two patients who presented with severe growth deficit due to homozygous loss-of-function mutations in GHRHR, their final heights reached the target height.

  16. Role of Protein and Amino Acids in Infant and Young Child Nutrition: Protein and Amino Acid Needs and Relationship with Child Growth.

    Uauy, Ricardo; Kurpad, Anura; Tano-Debrah, Kwaku; Otoo, Gloria E; Aaron, Grant A; Toride, Yasuhiko; Ghosh, Shibani

    2015-01-01

    Over a third of all deaths of children under the age of five are linked to undernutrition. At a 90% coverage level, a core group of ten interventions inclusive of infant and young child nutrition could save one million lives of children under 5 y of age (15% of all deaths) (Lancet 2013). The infant and young child nutrition package alone could save over 220,000 lives in children under 5 y of age. High quality proteins (e.g. milk) in complementary, supplementary and rehabilitation food products have been found to be effective for good growth. Individual amino acids such as lysine and arginine have been found to be factors linked to growth hormone release in young children via the somatotropic axis and high intakes are inversely associated with fat mass index in pre-pubertal lean girls. Protein intake in early life is positively associated with height and weight at 10 y of age. This paper will focus on examining the role of protein and amino acids in infant and young child nutrition by examining protein and amino acid needs in early life and the subsequent relationship with stunting.

  17. Growth hormone (GH)-releasing activity of chicken GH-releasing hormone (GHRH) in chickens.

    Harvey, S; Gineste, C; Gaylinn, B D

    2014-08-01

    Two peptides with sequence similarities to growth hormone releasing hormone (GHRH) have been identified by analysis of the chicken genome. One of these peptides, chicken (c) GHRH-LP (like peptide) was previously found to poorly bind to chicken pituitary membranes or to cloned and expressed chicken GHRH receptors and had little, if any, growth hormone (GH)-releasing activity in vivo or in vitro. In contrast, a second more recently discovered peptide, cGHRH, does bind to cloned and expressed cGHRH receptors and increases cAMP activity in transfected cells. The possibility that this peptide may have in vivo GH-releasing activity was therefore assessed. The intravenous (i.v.) administration of cGHRH to immature chickens, at doses of 3-100 μg/kg, significantly increased circulating GH concentrations within 10 min of injection and the plasma GH levels remained elevated for at least 30 min after the injection of maximally effective doses. The plasma GH responses to cGHRH were comparable with those induced by human (h) or porcine (p) GHRH preparations and to that induced by thyrotropin releasing hormone (TRH). In marked contrast, the i.v. injection of cGHRH-LP had no significant effect on circulating GH concentrations in immature chicks. GH release was also increased from slaughterhouse chicken pituitary glands perifused for 5 min with cGHRH at doses of 0.1 μg/ml or 1.0 μg/ml, comparable with GH responses to hGHRH1-44. In contrast, the perifusion of chicken pituitary glands with cGHRH-LP had no significant effect on GH release. In summary, these results demonstrate that cGHRH has GH-releasing activity in chickens and support the possibility that it is the endogenous ligand of the cGHRH receptor. Copyright © 2014 Elsevier Inc. All rights reserved.

  18. Growth Problems

    ... Development Infections Diseases & Conditions Pregnancy & Baby Nutrition & Fitness Emotions & Behavior School & Family Life First Aid & Safety Doctors & ... hypothyroidism is feeling tired or sluggish. A blood test measuring thyroid ... not affect intelligence or brain function. The cause of growth hormone ...

  19. Growth Disorders

    ... the changes your body goes through during puberty. Puberty is the stage of your life when sexual development happens, like breast development and menstrual periods in girls and growth of the penis and testicles in boys. One of the body ...

  20. Population growth and economic growth.

    Narayana, D L

    1984-01-01

    This discussion of the issues relating to the problem posed by population explosion in the developing countries and economic growth in the contemporary world covers the following: predictions of economic and social trends; the Malthusian theory of population; the classical or stationary theory of population; the medical triage model; ecological disaster; the Global 2000 study; the limits to growth; critiques of the Limits to Growth model; nonrenewable resources; food and agriculture; population explosion and stabilization; space and ocean colonization; and the limits perspective. The Limits to Growth model, a general equilibrium anti-growth model, is the gloomiest economic model ever constructed. None of the doomsday models, the Malthusian theory, the classical stationary state, the neo-Malthusian medical triage model, the Global 2000 study, are so far reaching in their consequences. The course of events that followed the publication of the "Limits to Growth" in 1972 in the form of 2 oil shocks, food shock, pollution shock, and price shock seemed to bear out formally the gloomy predictions of the thesis with a remarkable speed. The 12 years of economic experience and the knowledge of resource trends postulate that even if the economic pressures visualized by the model are at work they are neither far reaching nor so drastic. Appropriate action can solve them. There are several limitations to the Limits to Growth model. The central theme of the model, which is overshoot and collapse, is unlikely to be the course of events. The model is too aggregative to be realistic. It exaggerates the ecological disaster arising out of the exponential growth of population and industry. The gross underestimation of renewable resources is a basic flaw of the model. The most critical weakness of the model is its gross underestimation of the historical trend of technological progress and the technological possiblities within industry and agriculture. The model does correctly emphasize

  1. Suppression of GHS-R in AgRP neurons mitigates diet-induced obesity by activating thermogenesis

    Ghrelin, an orexigenic hormone released primarily from the gut, signals the hypothalamus to stimulate growth hormone release, enhance appetite and promote weight gain. The ghrelin receptor, aka Growth Hormone Secretagogue Receptor (GHS-R), is highly expressed in the brain, with highest expression in...

  2. Excessive growth.

    Narayanaswamy, Vasudha; Rettig, Kenneth R; Bhowmick, Samar K

    2008-09-01

    Tall stature and excessive growth syndrome are a relatively rare concern in pediatric practice. Nevertheless, it is important to identify abnormal accelerated growth patterns in children, which may be the clue in the diagnosis of an underlying disorder. We present a case of pituitary gigantism in a 2 1/2-year-old child and discuss the signs, symptoms, laboratory findings, and the treatment. Brief discussions on the differential diagnosis of excessive growth/tall stature have been outlined. Pituitary gigantism is very rare in the pediatrics age group; however, it is extremely rare in a child that is less than 3 years of age. The nature of pituitary adenoma and treatment options in children with this condition have also been discussed.

  3. Dietary intake, growth and development of children with ADHD in a randomized clinical trial of Ritalin and Melatonin co-administration: Through circadian cycle modification or appetite enhancement?

    Mostafavi, Seyed-Ali; Mohammadi, Mohammad Reza; Hosseinzadeh, Payam; Eshraghian, Mohammad Reza; Akhondzadeh, Shahin; Hosseinzadeh-Attar, Mohammad Javad; Ranjbar, Elham; Kooshesh, Seyed Mohammad-Ali; Keshavarz, Seyed-Ali

    2012-01-01

    It is postulated that ritalin may adversely affect sleep, appetite, weight and growth of some children with ADHD. Therefore, we aimed to evaluate melatonin supplementation effects on dietary intake, growth and development of children with ADHD treated with ritalin through circadian cycle modification and appetite mechanisms. After obtaining consent from parents, 50 children aged 7-12 with combined form of AD/HD were randomly divided into two groups based on gender blocks: one received melatonin (3 or 6 mg based on weight) combined with ritalin (1mg/kg) and the other took placebo combined with ritalin (1mg/kg) in a double blind randomized clinical trial. Three-day food record, and standard weight and height of children were evaluated prior to the treatment and 8 weeks after the treatment. Children's appetite and sleep were evaluated in weeks 0, 2, 4 and 8. Hypotheses were then analyzed using SPSS17. Paired sample t-test showed significant changes in sleep latency (23.15±15.25 vs. 17.96±11.66; p=0.047) and total sleep disturbance score (48.84±13.42 vs. 41.30±9.67; p=0.000) before and after melatonin administration, respectively. However, appetite and food intake did not change significantly during the study. Sleep duration and appetite were significantly correlated in melatonin group (Pearson r=0.971, p=0.029). Mean height (138.28±16.24 vs. 141.35±16.78; P=0.000) and weight (36.73±17.82 vs. 38.97±17.93; P=0.005) were significantly increased in melatonin treated children before and after the trial. Administration of melatonin along with ritalin improves height and weight growth of children. These effects may be attributed to circadian cycle modification, increasing sleep duration and the consequent more growth hormone release during sleep.

  4. Cow body condition affects the hormonal release of ovarian cells and their responses to gonadotropic and metabolic hormones

    Sirotkin, A. V.; Makarevich, A. V.; Laurinčík, Jozef; Alawasel, S.; Harrath, A. H.

    2018-01-01

    Roč. 110, č. 3 (2018), s. 142-147 ISSN 0093-691X R&D Projects: GA MŠk EF15_003/0000460 Institutional support: RVO:67985904 Keywords : ovary * body condition * progesterone Subject RIV: EB - Genetics ; Molecular Biology OBOR OECD: Developmental biology Impact factor: 1.986, year: 2016

  5. Luteinizing hormone-releasing hormone inactivation by purified pituitary plasma membranes: effects of receptor-binding studies.

    Clayton, R N; Shakespear, R A; Duncan, J A; Marshall, J C

    1979-05-01

    Inactivation of LHRH by purified bovine pituitary plasma membranes was studied in vitro. After incubation of [125I]iodo-LHRH with plasma membranes, the amount of tracer bound to the pellet was measured, and the integrity of the unbound tracer in the supernatant was assessed. Reduction in ability to bind to anti-LHRH serum and to rebind to plasma membranes together with altered electrophoretic mobility on polyacrylamide gels showed that the unbound [125I]iodo-LHRH was inactivated. LHRH inactivation occurred rapidly and was dependent upon membrane concentration and incubation temperature. These results indicate that hormone inactivation must be taken into account in the interpretation of LHRH-receptor interactions. During 37 C incubations, the apparent absence of specific LHRH binding can be explained by inactivation of tracer hormone. Significant LHRH inactivation also occurred at 0 C, which in part explains the insensitivity of LHRH receptor assays. Assessment of LHRH inactivation by different particulate subcellular fractions of pituitary tissue showed that the inactivating enzyme was associated with the plasma membranes; other organelles did not alter LHRH. The enzyme appeared to be an integral part of the plasma membrane structure, since enzymic activity could not be removed by washing without reducing specific LHRH binding. Additionally, reduction of LHRH inactivation by the inhibitors Bacitracin and Trasylol and by magnesium was also accompanied by reduced LHRH binding. Previous studies have shown that the majority of LHRH binding to pituitary plasma membranes is to the low affinity site (approximately 10(-6) M), but the significance of this binding has been uncertain. Our findings indicate that low affinity binding probably represents binding of LHRH to the inactivating enzyme. The LHRH analog, D-Ser6(TBu), des Gly10, ethylamide, has greater biological activity than LHRH and is not inactivated to a significant extent by pituitary plasma membranes. The enhanced biological activity of the analog, therefore, may be due to its resistance to inactivation by enzymes on the pituitary cell surface. The membrane-associated inactivating enzyme could play an important role in vivo in determining the concentration of intact LHRH available at the receptor site which initiates gonadotropin release.

  6. Stress hormone release is a key component of the metabolic response to lipopolysaccharide (LPS): studies in hypopituitary and healthy subjects

    Bach, Ermina; Møller, Andreas Buch; Jørgensen, Jens Otto Lunde

    2016-01-01

    OBJECTIVE: Lipopolysaccharide (LPS) generates acute and chronic inflammatory and metabolic responses during acute illness and in the pathogenesis of the metabolic syndrome, type 2 diabetes and cardiovascular disease, but it is unclear whether these responses depend on intact pituitary release...... but not in HP. LPS increased whole body palmitate fluxes (3-fold) and decreased palmitate specific activity 40-50 % in CTR, but not in HP. G(0)/G(1) Switch Gene 2 (G0S2 - an inhibitor of lipolysis) adipose tissue mRNA was decreased in CTR. LPS increased phenylalanine fluxes significantly more in CTR, whereas...

  7. The nervus terminalis of the guinea pig: a new luteinizing hormone-releasing hormone (LHRH) neuronal system.

    Schwanzel-Fukuda, M; Silverman, A J

    1980-05-15

    Immunoreactive LHRH-like material has been found in the cells and fibers of the nervus terminalis in fetal and adult guinea pig brains. LHRH-containing neurons and axons are seen in the nasal mucosa intermingled with fibers of the olfactory nerves, in ganglia along the ventromedial surfaces of the olfactory bulbs and forebrain, and in clusters surrounding perforating branches of the anterior cerebral artery in the regions of the septal nuclei and olfactory tubercle. Nonreactive neurons are found adjacent to the LHRH-positive cells in all of the ganglia. LHRH-immunoreactive cells and axons of the nervus terminalis are in intimate contact with cerebral blood vessels and the cerebrospinal fluid along the intracranial course of this nerve, deep to the meninges. The possible involvement of these structures in the neural mechanisms of sexual behavior and the neurohormonal regulation of reproductive function are discussed.

  8. Effect of gonadotropin secretion rate on the radiosensitivity of the rat luteinizing hormone-releasing hormone neuron and gonadotroph

    Winterer, J.; Barnes, K.M.; Lichter, A.S.; Deluca, A.M.; Loriaux, D.L.; Cutler, G.B. Jr.

    1988-01-01

    To test the hypothesis that the functional state of hypothalamic LHRH neurons and pituitary gonadotrophs might alter their radiosensitivity, we determined the experimental conditions under which the gonadotropin response to castration could be impaired by a single dose of cranial irradiation. Single doses of cranial irradiation greater than 2000 rads were lethal to unshielded rats. Shielding of the oropharynx and esophagus allowed the animals to survive doses up to 5000 rads. Doses between 2000 and 5000 rads had no effect on basal gonadotropin levels for as long as 3 months after irradiation. Irradiation caused a dose- and time-dependent impairment, however, in the gonadotropin response to castration. Impairment of the gonadotropin levels of castrate animals occurred in animals that were irradiated either before or after castration. However, rats irradiated in the castrate state showed a decreased susceptibility to irradiation damage. Additionally, stimulation of the pituitary by LHRH agonist (LHRHa) 3 h before irradiation significantly reduced the impairment of gonadotropin secretion 12-20 weeks after irradiation (P less than 0.05). Thus, increased functional activity of the rat hypothalamus or pituitary at the time of irradiation, induced by either castration or acute LHRHa administration, was associated with some protection against the gonadotropin-lowering effect of irradiation. Based upon these data, we hypothesize that stimulation of gonadotropin secretion at the time of therapeutic cranial irradiation in humans might protect against subsequent impairment of gonadotropin secretion

  9. Glucose-induced incretin hormone release and inactivation are differently modulated by oral fat and protein in mice

    Gunnarsson, P Thomas; Winzell, Maria Sörhede; Deacon, Carolyn F

    2006-01-01

    Monounsaturated fatty acids, such as oleic acid (OA), and certain milk proteins, especially whey protein (WP), have insulinotropic effects and can reduce postprandial glycemia. This effect may involve the incretin hormones glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like pepti...

  10. Effect of dietary macronutrients on postprandial incretin hormone release and satiety in obese and normal-weight women.

    Wikarek, Tomasz; Chudek, Jerzy; Owczarek, Aleksander; Olszanecka-Glinianowicz, Magdalena

    2014-01-28

    The aim of the present study was to assess the effect of dietary macronutrients on postprandial incretin responses and satiety and hunger sensation in obese and normal-weight women. A total of eleven obese and nine normal-weight women were recruited for the assessment of plasma concentrations of glucagon-like peptide-1 (GLP-1), glucose-dependent insulinotropic polypeptide (GIP) and insulin and the sensation of satiety and hunger using a visual analogue scale before and during a 6 h period after administration of three different macronutrient test meals. The AUCtotal GLP-1 and AUCtotal GIP values were decreased in obese women after the consumption of a fatty meal and all the test meals, respectively. However, the AUCtotal insulin value after a carbohydrate meal was greater in the obese group. The AUCtotal satiety value was decreased only after the intake of the protein meal in obese women when compared with normal-weight women. After the consumption of the fatty meal, a significant positive correlation between maximum satiety sensation and the AUCtotal GLP-1 value in the obese group and that between minimum hunger sensation and the AUCtotal GLP-1 value in the normal-weight group were observed. In conclusion, the findings of the present study suggest that: (1) satiety sensation after consumption of carbohydrate and protein meals in the obese group is related to the postprandial insulin response, while after consumption of a fatty meal, it is related to the postprandial GLP-1 release; (2) the postprandial GIP response does not influence the sensation of satiety and hunger; (3) the reduced GLP-1 release after the intake of a fatty meal in obese individuals may explain impaired satiety sensation; (4) the impaired postprandial GIP response is not related to the consumption of macronutrients and may be the early indicator of incretin axis dysfunction in obese women.

  11. In vivo and in vitro effects of chromium VI on anterior pituitary hormone release and cell viability

    Quinteros, Fernanda A.; Poliandri, Ariel H.B.; Machiavelli, Leticia I.; Cabilla, Jimena P.; Duvilanski, Beatriz H.

    2007-01-01

    Hexavalent chromium (Cr VI) is a highly toxic metal and an environmental pollutant. Different studies indicate that Cr VI exposure adversely affects reproductive functions. This metal has been shown to affect several tissues and organs but Cr VI effects on pituitary gland have not been reported. Anterior pituitary hormones are central for the body homeostasis and have a fundamental role in reproductive physiology. The aim of this study was to evaluate the effect of Cr VI at the pituitary level both in vivo and in vitro. We showed that Cr VI accumulates in the pituitary and hypothalamus, and decreases serum prolactin levels in vivo but observed no effects on LH levels. In anterior pituitary cells in culture, the effect of Cr VI on hormone secretion followed the same differential pattern. Besides, lactotrophs were more sensitive to the toxicity of the metal. As a result of oxidative stress generation, Cr VI induced apoptosis evidenced by nuclear fragmentation and caspase 3 activation. Our results indicate that the anterior pituitary gland can be a target of Cr VI toxicity in vivo and in vitro, thus producing a negative impact on the hypothalamic-pituitary-gonadal axis and affecting the normal endocrine function

  12. In vivo and in vitro effects of chromium VI on anterior pituitary hormone release and cell viability.

    Quinteros, Fernanda A; Poliandri, Ariel H B; Machiavelli, Leticia I; Cabilla, Jimena P; Duvilanski, Beatriz H

    2007-01-01

    Hexavalent chromium (Cr VI) is a highly toxic metal and an environmental pollutant. Different studies indicate that Cr VI exposure adversely affects reproductive functions. This metal has been shown to affect several tissues and organs but Cr VI effects on pituitary gland have not been reported. Anterior pituitary hormones are central for the body homeostasis and have a fundamental role in reproductive physiology. The aim of this study was to evaluate the effect of Cr VI at the pituitary level both in vivo and in vitro. We showed that Cr VI accumulates in the pituitary and hypothalamus, and decreases serum prolactin levels in vivo but observed no effects on LH levels. In anterior pituitary cells in culture, the effect of Cr VI on hormone secretion followed the same differential pattern. Besides, lactotrophs were more sensitive to the toxicity of the metal. As a result of oxidative stress generation, Cr VI induced apoptosis evidenced by nuclear fragmentation and caspase 3 activation. Our results indicate that the anterior pituitary gland can be a target of Cr VI toxicity in vivo and in vitro, thus producing a negative impact on the hypothalamic-pituitary-gonadal axis and affecting the normal endocrine function.

  13. [Role of estrogen-sensitive neurons in the arcuate region of the hypothalamus in the mechanism of luteinizing hormone release].

    Babichev, V N; Ignatkov, V Ia

    1978-01-01

    Experiments were conducted on rats; estradiol brought to the arcuate region of the hypothalamus by means of microionophoresis led to the increase of the region of the hypothalamus by means of microionophoresis led to the increase of the blood luteinizing hormone (LH) level during the following stages of the estral cycle-diestrus 1, diestrus 2, and the first half day of the proestrus; as to the second half of the proestrus day--estradiol decreased its level. Changes in the LH level in the hypophysis under the influence of the microionophoretic introduction of estradiol into the arcuate region occurred during the second half of the day of diestrus 2 (reduction), and during the estrus (elevation). In the majority of cases a rise of the blood level was combined with the neuron activation in the arcuate region under the influence of estradiol.

  14. Regulation of Thyroid-stimulating Hormone Release from the Pituitary by Thyroxine during Metamorphosis in Xenopus laevis

    Environmentally-relevant chemicals such as perchlorate have the ability to disrupt the hypothalamo-pituitary-thyroid (HPT) axis of exposed individuals. Larval anurans are a particularly suitable model species for studying the effects of thyroid-disrupting chemicals (TDCs) becaus...

  15. Potentiating effects of GHRH analogs on the response to chemotherapy

    Schally, Andrew V; Perez, Roberto; Block, Norman L; Rick, Ferenc G

    2015-01-01

    Growth hormone releasing hormone (GHRH) from hypothalamus nominatively stimulates growth hormone release from adenohypophysis. GHRH is also produced by cancers, acting as an autocrine/paracrine growth factor. This growth factor function is seen in lymphoma, melanoma, colorectal, liver, lung, breast, prostate, kidney, bladder cancers. Pituitary type GHRH receptors and their splice variants are also expressed in these malignancies. Synthetic antagonists of the GHRH receptor inhibit proliferatio...

  16. Simulating Population Growth.

    Byington, Scott

    1997-01-01

    Presents a strategy to help students grasp the important implications of population growth. Involves an interactive demonstration that allows students to experience exponential and logistic population growth followed by a discussion of the implications of population-growth principles. (JRH)

  17. AMSAA Reliability Growth Guide

    Broemm, William

    2000-01-01

    ... has developed reliability growth methodology for all phases of the process, from planning to tracking to projection. The report presents this methodology and associated reliability growth concepts.

  18. Green growth in fisheries

    Nielsen, Max; Ravensbeck, Lars; Nielsen, Rasmus

    2014-01-01

    harming the environment. Fishery is an environment-dependent sector and it has been argued that there is no potential for green growth in the sector owing to global overexploitation, leaving no scope for production growth. The purpose of this paper is to explain what green growth is and to develop......Climate change and economic growth have gained a substantial amount of attention over the last decade. Hence, in order to unite the two fields of interest, the concept of green growth has evolved. The concept of green growth focuses on how to achieve growth in environment-dependent sectors, without...... a conceptual framework. Furthermore, the aim is to show that a large green growth potential actually exists in fisheries and to show how this potential can be achieved. The potential green growth appears as value-added instead of production growth. The potential can be achieved by reducing overcapacity...

  19. The relationship between N-terminal prosomatostatin, all-cause and cardiovascular mortality in patients with type 2 diabetes mellitus (ZODIAC-35)

    van Dijk, Peter R; Landman, Gijs W D; van Essen, Larissa; Struck, Joachim; Groenier, Klaas H; Bilo, Henk J G; Bakker, Stephan J L; Kleefstra, Nanne

    2015-01-01

    BACKGROUND: The hormone somatostatin inhibits growth hormone release from the pituitary gland and is theoretically linked to diabetes and diabetes related complications. This study aimed to investigate the relationship between levels of the stable somatostatin precursor, N-terminal prosomatostatin

  20. The relationship between N-terminal prosomatostatin, all-cause and cardiovascular mortality in patients with type 2 diabetes mellitus (ZODIAC-35)

    van Dijk, Peter R; Landman, Gijs W D; van Essen, Larissa; Struck, Joachim; Groenier, Klaas H; Bilo, Henk J G; Bakker, Stephan J L; Kleefstra, Nanne

    2015-01-01

    Background: The hormone somatostatin inhibits growth hormone release from the pituitary gland and is theoretically linked to diabetes and diabetes related complications. This study aimed to investigate the relationship between levels of the stable somatostatin precursor, N-terminal prosomatostatin

  1. Globalization, Growth and Poverty

    One-pagers are a publication of IDRC's “Globalization, Growth and Poverty” Program Initiative, and are based on ... countries, mainly the fast-growing economies of East Asia. ... had no significant overall impact on investment and growth. Other.

  2. Measuring multifactor productivity growth

    Wölfl, A.; Hájková, Dana

    -, 2007/5 (2007), s. 1-45 Institutional research plan: CEZ:AV0Z70850503 Keywords : multifactor productivity growth * GDP growth * measuring Subject RIV: AH - Economics http://www.oecd.org/dataoecd/61/17/39522985.pdf

  3. Growth hormone test

    ... is called acromegaly . In children it is called gigantism . Too little growth hormone can cause a slow ... growth due to excess GH during childhood, called gigantism. (A special test is done to confirm this ...

  4. CDC Child Growth Charts

    U.S. Department of Health & Human Services — CDC child growth charts consist of a series of percentile curves that illustrate the distribution of selected body measurements in U.S. children. Pediatric growth...

  5. Growth hormone stimulation test

    ... this page: //medlineplus.gov/ency/article/003377.htm Growth hormone stimulation test To use the sharing features on this page, please enable JavaScript. The growth hormone (GH) stimulation test measures the ability of ...

  6. Normal growth and development

    ... page: //medlineplus.gov/ency/article/002456.htm Normal growth and development To use the sharing features on this page, please enable JavaScript. A child's growth and development can be divided into four periods: ...

  7. Pituitary tumor evaluation

    Albertson, B.; Binney, S.

    1995-01-01

    This paper describes research on the following: the structure of 10 B 10 -ovine corticotropin releasing hormone and 10 B 10 -growth hormone releasing hormone; the BNCT effect on AtT-20 cell 10 B 10 -CRH incubations in vitro; BNCT effects on GH 4 C 1 cell 10 B 10 growth hormone releasing factor incubation in vitro; and competitive inhibition of AtT-20 cell BNCT effect

  8. Systemic Crises and Growth

    Romain Ranciere; Aaron Tornell; Frank Westermann

    2005-01-01

    In this paper, we document the fact that countries that have experienced occasional financial crises have, on average, grown faster than countries with stable financial conditions. We measure the incidence of crisis with the skewness of credit growth, and find that it has a robust negative effect on GDP growth. This link coexists with the negative link between variance and growth typically found in the literature. To explain the link between crises and growth we present a model where contract...

  9. Urban tree growth modeling

    E. Gregory McPherson; Paula J. Peper

    2012-01-01

    This paper describes three long-term tree growth studies conducted to evaluate tree performance because repeated measurements of the same trees produce critical data for growth model calibration and validation. Several empirical and process-based approaches to modeling tree growth are reviewed. Modeling is more advanced in the fields of forestry and...

  10. Unemployment and endogenous growth

    van Schaik, A.B.T.M.; de Groot, H.L.F.

    1995-01-01

    In this paper we develop a two-sector endogenous growth model with a dual labour market, based on efficiency wages. Growth is driven by intentional R&D performed in the high-tech and high-wage sector. It is examined how a change in rivalry among firms affects simultaneously growth and unemployment.

  11. Toddler Growth and Development

    ... the AAP Schedule of Well-Child Care Visits . ​​ Toddler Growth & Development Physical Skills Walks alone Pulls toys behind when ... 18 to 23 Month Old Language Delays in Toddlers: Information for Parents ... Physical Appearance and Growth: Your 1 Year Old Physical Appearance and Growth: ...

  12. Growth Charts (For Parents)

    ... Staying Safe Videos for Educators Search English Español Growth Charts KidsHealth / For Parents / Growth Charts What's in ... Problem? Print en español Tablas de crecimiento About Growth Charts Look at any class picture, and you' ...

  13. Growth hormone, growth factors, and acromegaly

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

    1987-01-01

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

  14. Dietary intake, growth and development of children with ADHD in a randomized clinical trial of Ritalin and Melatonin co-administration: Through circadian cycle modification or appetite enhancement?

    Seyed-Ali Mostafavi

    2012-09-01

    Full Text Available Objective: It is postulated that ritalin may adversely affect sleep, appetite, weight and growth of some children with ADHD. Therefore, we aimed to evaluate melatonin supplementation effects on dietary intake, growth and development of children with ADHD treated with ritalin through circadian cycle modification and appetite mechanisms.Method: After obtaining consent from parents, 50 children aged 7-12 with combined form of AD/HD were randomly divided into two groups based on gender blocks: one received melatonin (3 or 6 mg based on weight combined with ritalin (1mg/kg and the other took placebo combined with ritalin (1mg/kg in a double blind randomized clinical trial. Three-day food record, and standard weight and height of children were evaluated prior to the treatment and 8 weeks after the treatment. Children’s appetite and sleep were evaluated in weeks 0, 2, 4 and 8. Hypotheses were then analyzed using SPSS17.Results: Paired sample t-test showed significant changes in sleep latency (23.15±15.25 vs. 17.96±11.66; p=0.047 and total sleep disturbance score (48.84±13.42 vs. 41.30±9.67; p=0.000 before and after melatonin administration, respectively. However, appetite and food intake did not change significantly during the study. Sleep duration and appetite were significantly correlated in melatonin group (Pearson r=0.971, p=0.029. Mean height (138.28±16.24 vs. 141.35±16.78; P=0.000 and weight (36.73±17.82 vs. 38.97±17.93; P=0.005 were significantly increased in melatonin treated children before and after the trial.Conclusion: Administration of melatonin along with ritalin improves height and weight growth of children. These effects may be attributed to circadian cycle modification, increasing sleep duration and the consequent more growth hormone release during sleep.

  15. Lung growth and development.

    Joshi, Suchita; Kotecha, Sailesh

    2007-12-01

    Human lung growth starts as a primitive lung bud in early embryonic life and undergoes several morphological stages which continue into postnatal life. Each stage of lung growth is a result of complex and tightly regulated events governed by physical, environmental, hormonal and genetic factors. Fetal lung liquid and fetal breathing movements are by far the most important determinants of lung growth. Although timing of the stages of lung growth in animals do not mimic that of human, numerous animal studies, mainly on sheep and rat, have given us a better understanding of the regulators of lung growth. Insight into the genetic basis of lung growth has helped us understand and improve management of complex life threatening congenital abnormalities such as congenital diaphragmatic hernia and pulmonary hypoplasia. Although advances in perinatal medicine have improved survival of preterm infants, premature birth is perhaps still the most important factor for adverse lung growth.

  16. Adult growth hormone deficiency

    Vishal Gupta

    2011-01-01

    Full Text Available Adult growth hormone deficiency (AGHD is being recognized increasingly and has been thought to be associated with premature mortality. Pituitary tumors are the commonest cause for AGHD. Growth hormone deficiency (GHD has been associated with neuropsychiatric-cognitive, cardiovascular, neuromuscular, metabolic, and skeletal abnormalities. Most of these can be reversed with growth hormone therapy. The insulin tolerance test still remains the gold standard dynamic test to diagnose AGHD. Growth hormone is administered subcutaneously once a day, titrated to clinical symptoms, signs and IGF-1 (insulin like growth factor-1. It is generally well tolerated at the low-doses used in adults. Pegylated human growth hormone therapy is on the horizon, with a convenient once a week dosing.

  17. Aid and growth regressions

    Hansen, Henrik; Tarp, Finn

    2001-01-01

    This paper examines the relationship between foreign aid and growth in real GDP per capita as it emerges from simple augmentations of popular cross country growth specifications. It is shown that aid in all likelihood increases the growth rate, and this result is not conditional on ‘good’ policy....... investment. We conclude by stressing the need for more theoretical work before this kind of cross-country regressions are used for policy purposes.......This paper examines the relationship between foreign aid and growth in real GDP per capita as it emerges from simple augmentations of popular cross country growth specifications. It is shown that aid in all likelihood increases the growth rate, and this result is not conditional on ‘good’ policy...

  18. City Population Growth and Economic Growth

    Freire-Gibb, L. Carlos

    2008-01-01

    This article looks at the relationship between city population growth (intimately related to population proximity), and economic development. The hypothesis is that wherever dynamic and inclusive networks exist, there are more opportunities for economic development in this place. When these types...... of networks choose a tool (project, policy) to implement in the city, success will be more likely. Furthermore, virtuous circles will arise. The author gives an overview of two historical cases in urban growth, in Europe (1200-1800) and the U.S.A. (1800 to today)....

  19. Earthquakes and economic growth

    Fisker, Peter Simonsen

    2012-01-01

    This study explores the economic consequences of earthquakes. In particular, it is investigated how exposure to earthquakes affects economic growth both across and within countries. The key result of the empirical analysis is that while there are no observable effects at the country level, earthquake exposure significantly decreases 5-year economic growth at the local level. Areas at lower stages of economic development suffer harder in terms of economic growth than richer areas. In addition,...

  20. Luxury-based Growth

    Shiro Kuwahara

    2006-01-01

    Assuming that there exists a preference for luxury goods and a knowledge spillover from luxury goods production to goods production, this paper constructs an endogenous economic growth model. The model predicts two steady states: one is a steady positive growth state with regard to luxury goods production, and the other is a zero growth state in the absence of luxury goods production. Thus, this study examines the polarization of economies based on luxury goods consumption

  1. Robust Growth Determinants

    Doppelhofer, Gernot; Weeks, Melvyn

    2011-01-01

    This paper investigates the robustness of determinants of economic growth in the presence of model uncertainty, parameter heterogeneity and outliers. The robust model averaging approach introduced in the paper uses a flexible and parsi- monious mixture modeling that allows for fat-tailed errors compared to the normal benchmark case. Applying robust model averaging to growth determinants, the paper finds that eight out of eighteen variables found to be significantly related to economic growth ...

  2. Thailand's growth rebalancing

    Jitsuchon, Somchai; Sussangkarn, Chalongphob

    2009-01-01

    This paper reviews Thailand's structural changes, the 1997 crisis experience, and recovery and lessons from the crisis. The paper then discusses the impacts of the subprime crisis on the Thai economy and the policy responses to date. The paper ends by discussing strategies to rebalance growth by reducing the dependence on exports as the main growth engine. The recovery from the 1997 crisis left Thailand more dependent than ever on exports as the main engine of growth, with the ratio of export...

  3. Smart Growth and Transportation

    Describes the relationship between smart growth and transportation, focusing smart and sustainable street design, transit-oriented development, parking management, sustainable transportation planning, and related resources.

  4. FDI- Economic Growth Nexus

    Bujac, Andreea Ioana; Corado Cretu, Emanuel

    2017-01-01

    Conducting a systematic literature review on the topic of FDI and Economic Growth and investigating this relationship, along with the determinants of an economy that attract FDI and the externalities resulting from Foreign activities, it is found that FDI does have a positive effect on a host...... country’s economic growth but only with the preexistence of certain determinants which facilitate the absorption capacity of the host country on reaping the spillover effects (externalities) of FDI. Lastly, a framework was built to illustrate the interaction between FDI, Determinants and condition...... of the host economy, barriers to growth, economic growth and externalities....

  5. Aid, growth, and development

    Arndt, Channing; Jones, Edward Samuel; Tarp, Finn

    2010-01-01

    The micro-macro paradox has been revived. Despite broadly positive evaluations at the micro- and meso-levels, recent literature doubts the ability of foreign aid to foster economic growth and development. This paper assesses the aid-growth literature and, taking inspiration from the program...... evaluation literature, we re-examine key hypotheses. In our findings, aid has a positive and statistically significant causal effect on growth over the long run, with confidence intervals conforming to levels suggested by growth theory. Aid remains a key tool for enhancing the development prospects of poor...

  6. Optimising growth in phenylketonuria

    Dokoupil, Katharina; Gokmen-Ozel, Hulya; Lammardo, Anna Maria

    2012-01-01

    populations. We reviewed the literature searching for evidence regarding PKU and growth as well as possible links between dietary management of PKU and growth. The search retrieved only limited evidence on the effect of PKU and its dietary management on growth. Physical development in PKU remains an under....... Protein requirements in dietary management of PKU are met mostly from Phe-free protein substitutes with the intake of natural protein restricted to patient tolerance. Several reports have suggested that growth in early childhood in PKU is sub-optimal, relative to non-PKU control groups or reference...

  7. Triplet ultrasound growth parameters.

    Vora, Neeta L; Ruthazer, Robin; House, Michael; Chelmow, David

    2006-03-01

    To create ultrasound growth curves for normal growth of fetal triplets using statistical methodology that properly accounts for similarities of growth of fetuses within a mother as well as repeated measurements over time for each fetus. In this longitudinal study, all triplet pregnancies managed at a single tertiary center from 1992-2004 were reviewed. Fetuses with major anomalies, prior selective reduction, or fetal demise were excluded. Data from early and late gestation in which there were fewer than 30 fetal measurements available for analysis were excluded. We used multilevel models to account for variation in growth within a single fetus over time, variations in growth between multiple fetuses within a single mother, and variations in fetal growth between mothers. Medians (50th), 10th, and 90th percentiles were estimated by the creation of multiple quadratic growth models from bootstrap samples adapting a previously published method to compute prediction intervals. Estimated fetal weight was derived from Hadlock's formula. One hundred fifty triplet pregnancies were identified. Twenty-seven pregnancies were excluded for the following reasons: missing records (23), fetal demise (3), and fetal anomaly (1). The study group consisted of 123 pregnancies. The gestational age range was restricted to 14-34 weeks. Figures and tables were developed showing medians, 10th and 90th percentiles for estimated fetal weight, femur length, biparietal diameter, abdominal circumference, and head circumference. Growth curves for triplet pregnancies were derived. These may be useful for identification of abnormal growth in triplet fetuses. III.

  8. Incentives and Earnings Growth

    Frederiksen, Anders

    2013-01-01

    The career prospects of newly recruited employees differ substantially within an organization. The stars experience considerable growth in earnings; others can hardly maintain their entry salaries. This article sheds light on the mechanisms generating the observed heterogeneity in earnings growth...... by investigating the effects that explicit short-run incentives and implicit incentives have on earnings growth. The model’s predictions are tested using personnel records from a large bank and are found to be consistent with the observed earnings growth during the first half of the employees’ careers....

  9. Sustainable growth in Europe

    Andreini, P.

    1993-01-01

    The measures till now adopted did not stop environmental deterioration in Europe and the growth of economic activities in the future will make the situation more and more heavy. The European Communities (EEC) Cabinet launched a long term program for a sustainable growth in Europe, which could conciliate economic needs with environmental protection. This paper presents the first part of the program

  10. Nutrition and growth

    Forbes, G.B.

    1977-07-01

    Longitudinal growth data on children who developed obesity during childhood reveal a distinct tendency for height gain to accelerate coincident with or after the onset of excessive weight gain. The magnitude of the relative height increment is related to the degree of overweight. Overnutrition accelerates growth, just as undernutrition retards it.

  11. Growth Modulation in Achondroplasia.

    McClure, Philip K; Kilinc, Eray; Birch, John G

    2017-09-01

    Achondroplasia is the most common skeletal dysplasia with a rate of nearly 1/10,000. The development of lower extremity deformity is well documented, and various modes of correction have been reported. There are no reports on the use of growth modulation to correct angular deformity in achondroplasia. Medical Records from 1985 to 2015 were reviewed for the diagnosis of achondroplasia and growth modulation procedures. Patients who had been treated for angular deformity of the legs by growth modulation were identified. A detailed analysis of their medical record and preoperative and final lower extremity radiographs was completed. Four patients underwent growth modulation procedures, all to correct existing varus deformity of the legs. Three of the 4 patients underwent bilateral distal femoral and proximal tibial growth modulation. The remaining patient underwent tibial correction only. Two of the 4 patients had a combined proximal fibular epiphysiodesis. All limbs had some improvement of alignment; however, 1 patient went on to bilateral osteotomies. Only 1 limb corrected to a neutral axis with growth modulation alone at last follow-up, initial implantation was done before 5 years of age. Growth modulation is an effective means for deformity correction in the setting of achondroplasia. However implantation may need to be done earlier than would be typical for patients without achondroplasia. Osteotomy may still be required after growth modulation for incomplete correction.

  12. Empowering growth in Pakistan?

    K.A. Siegmann (Karin Astrid); H. Majid (Hadia)

    2014-01-01

    textabstractPakistan's Vision 2025 connects a policy commitment to greater gender equality with inclusive growth. It prioritises a "good quality of life and high living standard for all citizens across regions, gender" and to "achieve an annual average growth rate of 7 to 8 per cent that is

  13. Strategic growth options

    Kulatilaka, N.; Perotti, E.C.

    1998-01-01

    We provide a strategic rationale for growth options under uncertainty and imperfect corn-petition. In a market with strategic competition, investment confers a greater capability to take advantage of future growth opportunities. This strategic advantage leads to the capture of a greater share of the

  14. Modeling Exponential Population Growth

    McCormick, Bonnie

    2009-01-01

    The concept of population growth patterns is a key component of understanding evolution by natural selection and population dynamics in ecosystems. The National Science Education Standards (NSES) include standards related to population growth in sections on biological evolution, interdependence of organisms, and science in personal and social…

  15. Cluster growth kinetics

    Dubovik, V.M.; Gal'perin, A.G.; Rikhvitskij, V.S.; Lushnikov, A.A.

    2000-01-01

    Processes of some traffic blocking coming into existence are considered as probabilistic ones. We study analytic solutions for models for the dynamics of both cluster growth and cluster growth with fragmentation in the systems of finite number of objects. Assuming rates constancy of both coalescence and fragmentation, the models under consideration are linear on the probability functions

  16. SLOWER BUT HEALTHIER GROWTH

    LAN XINZHEN

    2010-01-01

    @@ China's economic growth has slowed,economic statistics released on July 15 show,confirming market expectations.But officials said the country's economy is still on track. The recovery has gained traction in China,which registered a double-digit growth of 11.1 percent in the first half of this year.

  17. Trade, Growth, and Poverty

    Dollar, David; Kraay, Aart

    2001-01-01

    The evidence from individual cases and from cross-country analysis supports the view that globalization leads to faster growth and poverty reduction in poor countries. To determine the effect of globalization on growth, poverty, and inequality, the authors first identify a group of developing countries that are participating more in globalization. China, India, and several other large coun...

  18. Measures of Student Growth

    Texas Education Agency, 2016

    2016-01-01

    Beginning in the 2017-2018 school year, appraisal systems in Texas, whether the state-recommended system or a locally developed system, will need to include a measure of student growth at the individual teacher level. Student growth measures how much a student progresses academically during his or her time with a particular teacher. It takes into…

  19. Aid and Growth

    Arndt, Channing; Jones, Edward Samuel; Tarp, Finn

    , are being drawn on the basis of fragile evidence. This paper first assesses the aid-growth literature with a focus on recent contributions. The aid-growth literature is then framed, for the first time, in terms of the Rubin Causal Model, applied at the macroeconomic level. Our results show that aid has......The micro-macro paradox has been revived. Despite broadly positive evaluations at the micro and meso-levels, recent literature has turned decidedly pessimistic with respect to the ability of foreign aid to foster economic growth. Policy implications, such as the complete cessation of aid to Africa...... a positive and statistically significant causal effect on growth over the long run with point estimates at levels suggested by growth theory. We conclude that aid remains an important tool for enhancing the development prospects of poor nations....

  20. Rejuveniles and Growth

    Barnett, Richard C.; Bhattacharya, Joydeep

    Rejuveniles are "people who cultivate tastes and mind-sets tradi- tionally associated with those younger than themselves." (Noxon, 2006) In this paper, we study a standard AK growth model of overlapping generations populated by rejuve- niles. For our purposes, rejuveniles are old agents who derive...... utility from "keeping up" their consumption with that of the current young. We find that such cross-generational keeping up is capable of generating interesting equilibrium growth dynamics, including growth cycles. No such growth dynamics is possible either in the baseline model, one where...... no such generational consumption externality exists, or for almost any other form of keeping up. Steady-state growth in a world with rejuveniles may be higher than that obtained in the baseline model....

  1. Aid Effectiveness on Growth

    Doucouliagos, Hristos; Paldam, Martin

    The AEL (aid effectiveness literature) is econo¬metric studies of the macroeconomic effects of development aid. It contains about 100 papers of which 68 are reduced form estimates of theeffect of aid on growth in the recipient country. The raw data show that growth is unconnected to aid......, but the AEL has put so much structure on the data that all results possible have emerged. The present meta study considers both the best-set of the 68 papers and the all-set of 543 regressions published. Both sets have a positive average aid-growth elasticity, but it is small and insignificant: The AEL has...... betweenstudies is real. In particular, the aid-growth association is stronger for Asian countries, and the aid-growth association is shown to have been weaker in the 1970s....

  2. Aid and Growth

    Tarp, Finn; Mekasha, Tseday Jemaneh

    2013-01-01

    Recent litterature in the meta-analysis category where results from a range of studies are brought together throws doubt on the ability of foreign aid to foster economic growth and development. This article assesses what meta-analysis has to contribute to the litterature on the effectiveness...... of foreign aid in terms of growth impact. We re-examine key hypotheses, and find that the effect of aid on growth is positive and statistically significant. This significant effect is genuine, and not an artefact of publication selection. We also show why our results differ from those published elsewhere....

  3. Aid and Growth

    Mekasha, Tseday Jemaneh; Tarp, Finn

    Some recent literature in the meta-analysis category where results from a range of studies are brought together throws doubt on the ability of foreign aid to foster economic growth and development. This paper assesses what meta-analysis has to say about the effectiveness of foreign aid in terms...... of the growth impact. We re-examine key hypotheses, and find that the effect of aid on growth is positive and statistically significant. This significant effect is genuine, and not an artefact of publication selection. We also show why our results differ from those published elsewhere....

  4. Environment and Growth

    Horii, Ryo; Ikefuji, Masako

    . In a less developed country, this link, which we call “limits to growth,” emerges as the “poverty-environment trap,” which explains the persistent international inequality both in terms of income and environment. This link also threatens the sustainability of the world’s economic growth, particularly when...... the emission of greenhouse gases raises the risk of natural disasters. Stronger environmental policies are required to overcome this link. While there is a trade-off between the environment and growth in the short run, we show that an appropriate policy can improve both in the long run....

  5. Normal and abnormal growth plate

    Kumar, R.; Madewell, J.E.; Swischuk, L.E.

    1987-01-01

    Skeletal growth is a dynamic process. A knowledge of the structure and function of the normal growth plate is essential in order to understand the pathophysiology of abnormal skeletal growth in various diseases. In this well-illustrated article, the authors provide a radiographic classification of abnormal growth plates and discuss mechanisms that lead to growth plate abnormalities

  6. Growth assessment in diagnosis of Fetal Growth Restriction. Review.

    Albu, A R; Horhoianu, I A; Dumitrascu, M C; Horhoianu, V

    2014-06-15

    The assessment of fetal growth represents a fundamental step towards the identification of the true growth restricted fetus that is associated to important perinatal morbidity and mortality. The possible ways of detecting abnormal fetal growth are taken into consideration in this review and their strong and weak points are discussed. An important debate still remains about how to discriminate between the physiologically small fetus that does not require special surveillance and the truly growth restricted fetus who is predisposed to perinatal complications, even if its parameters are above the cut-off limits established. In this article, we present the clinical tools of fetal growth assessment: Symphyseal-Fundal Height (SFH) measurement, the fetal ultrasound parameters widely taken into consideration when discussing fetal growth: Abdominal Circumference (AC) and Estimated Fetal Weight (EFW); several types of growth charts and their characteristics: populational growth charts, standard growth charts, individualized growth charts, customized growth charts and growth trajectories.

  7. Plant Growth Promoting Rhizobacteria

    IAS Admin

    known to improve plant growth in many ways when compared to ... roles in agricultural productivity. ... Sustainable agriculture: Sustainable agriculture involves the successful management of agricultural re- ... For the first time Kloepper et al.

  8. Planar elliptic growth

    Mineev, Mark [Los Alamos National Laboratory

    2008-01-01

    The planar elliptic extension of the Laplacian growth is, after a proper parametrization, given in a form of a solution to the equation for areapreserving diffeomorphisms. The infinite set of conservation laws associated with such elliptic growth is interpreted in terms of potential theory, and the relations between two major forms of the elliptic growth are analyzed. The constants of integration for closed form solutions are identified as the singularities of the Schwarz function, which are located both inside and outside the moving contour. Well-posedness of the recovery of the elliptic operator governing the process from the continuum of interfaces parametrized by time is addressed and two examples of exact solutions of elliptic growth are presented.

  9. Floods and Mold Growth

    Mold growth may be a problem after flooding. Excess moisture in the home is cause for concern about indoor air quality primarily because it provides breeding conditions for pests, molds and other microorganisms.

  10. Environmentally Sustainable Economic Growth

    Stelian Brad

    2016-05-01

    Full Text Available Economic growth and sustainable development are important issues for social prosperity. Sustainable development strives for moderate and responsible use within the economic activity of the limited resources of our planet, whereas economic growth does not limit the resource exploitation and energy, being mainly focused on productivity increase. From this perspective, both conceptual and operational contradictions occur between the two pillars of prosperity. This paper looks to these contradictions and proposes some streams of intervention such as economic growth and environmental sustainability to operate in harmony. A structured framework for innovative problem solving is considered in this respect. Results of this research show that it is possible to induce smart measures in the economic system for directing businesses towards new paradigms where economic growth is possible without negative effects on environmental sustainability.

  11. Growth and Your Newborn

    ... drink alcohol, or use illegal drugs during pregnancy. Nutrition during pregnancy . Good nutrition is essential for a baby's growth in the uterus and beyond. A poor diet during pregnancy can affect how much a newborn weighs and ...

  12. Globalization, Growth and Poverty

    One-pagers are a publication of IDRC's “Globalization, Growth and Poverty” Program Initiative, and are based on findings from the ... Does exporting matter for the poor in South Africa? ... strategies to promote employment and higher wages in.

  13. Globalization, Growth and Poverty

    One-pagers are a publication of IDRC's “Globalization, Growth and Poverty” Program Initiative, and are ... great disparities, with earnings among urban workers with higher education being four or five times larger than those of illiterate rural.

  14. Growth of dopamine crystals

    Patil, Vidya, E-mail: vidya.patil@ruparel.edu; Patki, Mugdha, E-mail: mugdha.patki@ruparel.edu [D. G. Ruparel College, Senapati Bapat Marg, Mahim, Mumbai – 400 016 (India)

    2016-05-06

    Many nonlinear optical (NLO) crystals have been identified as potential candidates in optical and electro-optical devices. Use of NLO organic crystals is expected in photonic applications. Hence organic nonlinear optical materials have been intensely investigated due to their potentially high nonlinearities, and rapid response in electro-optic effect compared to inorganic NLO materials. There are many methods to grow organic crystals such as vapor growth method, melt growth method and solution growth method. Out of these methods, solution growth method is useful in providing constraint free crystal. Single crystals of Dopamine have been grown by evaporating the solvents from aqueous solution. Crystals obtained were of the size of orders of mm. The crystal structure of dopamine was determined using XRD technique. Images of crystals were obtained using FEG SEM Quanta Series under high vacuum and low KV.

  15. Intrauterine Growth Restriction

    ... org editorial staff Categories: Family Health, Infants and Toddlers, Pregnancy and Childbirth, WomenTags: Amniocentesis, Delivery - Cesarean, female, Growth and Development, Obstetrical, Obstetrical ultrasound, Pregnant Women, prenatal care September ...

  16. Growth in liquid media.

    Elbing, Karen; Brent, Roger

    2002-08-01

    The procedure for inoculating overnight (starter) cultures of E. coli from a single colony is described along with considerations for growing larger cultures. Also included are two methods for monitoring cell growth using a spectrophotometer or a hemacytometer.

  17. Armenia's Economic Growth Sustainability

    Hayakawa, Tatsuji

    2015-01-01

    Armenia enjoyed 15 years of uninterrupted high economic growth prior to the global financial crisis in 2009. Investment, particularly in the mining and metallurgy sectors, played a key role as a driver of economic growth. Remittances,mostly from Russia, had an effect in sustaining consumption and boosting construction. Armenia has shown some weaknesses in the external sector, due to demands for natural gas, mineral products, machinery, and equipment. Armenia's exports and FDI suffer from the ...

  18. Macroeconomics and Growth Policies

    Jayati Ghosh

    2007-01-01

    This United Nations Background Note on Macroeconomics and Growth provides practical guidance on how to operationalize alternative equitable and employment-generating macroeconomic and growth policies in National Development Strategies. This Policy Note has been developed in cooperation with UN agencies, and has been officially reviewed by distinguished academics/ development specialists such as Jose Antonio Ocampo, Jomo K.S. and Nobel Laureate Joseph Stiglitz.

  19. SMEs, Growth, and Poverty

    Beck, Thorsten; Demirgüç-Kunt, Asli

    2004-01-01

    This Note explores the relationship between the size of the small and medium-size enterprise (SME) sector and economic growth and poverty reduction. A new study finds no support for the widely held belief that SMEs promote higher growth and lower pover ty. But it does provide some support for the view that the quality of the business environment facing all firms, large and small, influen...

  20. FGF growth factor analogs

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

    2012-07-24

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

  1. Entrepreneurship, Information, and Growth

    Bunten, Devin; Weiler, Stephan; Weiler, Stephan; Zahran, Sammy

    2016-01-01

    We examine the contribution to economic growth of entrepreneurial “marketplace information” within a regional endogenous growth framework. Entrepreneurs are posited to provide an input to economic growth through the information revealed by their successes and failures. We empirically identify this information source with the regional variation in establishment births and deaths, which create geographic information asymmetries that influence subsequent entrepreneurial activity and economic growth. We find that local establishment birth and death rates are significantly and positively correlated with subsequent entrepreneurship for US counties. To account for the potential endogeneity caused by forward-looking entrepreneurs, we utilize instruments based on historic mining activity. We find that the information spillover component of local establishment birth and death rates have significant positive effects on subsequent entrepreneurship and employment growth for US counties and metropolitan areas. With the help of these intruments, we show that establishment births have a positive and significant effect on future employment growth within all counties, and that in line with the information hypothesis, local establishment death rates have a similar positive effect within metropolitan counties. PMID:27516625

  2. Bacterial growth kinetics

    Boonkitticharoen, V.; Ehrhardt, J.C.; Kirchner, P.T.

    1989-01-01

    Quantitative measurement of bacterial growth may be made using a radioassay technique. This method measures, by scintillation counting, the 14 CO 2 derived from the bacterial metabolism of a 14 C-labeled substrate. Mathematical growth models may serve as reliable tools for estimation of the generation rate constant (or slope of the growth curve) and provide a basis for evaluating assay performance. Two models, i.e., exponential and logistic, are proposed. Both models yielded an accurate fit to the data from radioactive measurement of bacterial growth. The exponential model yielded high precision values of the generation rate constant, with an average relative standard deviation of 1.2%. Under most conditions the assay demonstrated no changes in the slopes of growth curves when the number of bacteria per inoculation was changed. However, the radiometric assay by scintillation method had a growth-inhibiting effect on a few strains of bacteria. The source of this problem was thought to be hypersensitivity to trace amounts of toluene remaining on the detector

  3. Endogenous growth and the environment

    Withagen, C.A.A.M.; Vellinga, N.

    2001-01-01

    This paper examines the relationship between environmental policy and growth, from the perspective of endogenous growth theory. In particular three standard endogenous growth models are supplemented with environmental issues, such as pollution and exhaustibility of natural resources. It is found

  4. Endogenous growth and environmental policy

    Withagen, C.A.A.M.; Vellinga, N.

    2001-01-01

    This paper examines the relationship between environmental policy and growth, from the perspective of endogenous growth theory. In particular three standard endogenous growth models are supplemented with environmental issues, such as pollution and exhaustibility of natural resources. It is found

  5. Plasma and tissue insulin-like growth factor-I receptor (IGF-IR) as a prognostic marker for prostate cancer and anti-IGF-IR agents as novel therapeutic strategy for refractory cases: a review.

    Ozkan, Emine Elif

    2011-09-15

    Cancer database analysis indicates that prostate cancer is one of the most seen cancers in men meanwhile composing the leading cause of morbidity and mortality among developed countries. Current available therapies are surgery, radiotherapy and androgene ablation for prostate carcinoma. The response rate is as high nearly 90% however, most of these recur or become refractory and androgene independent (AI). Therefore recent studies intensified on molecular factors playing role on development of prostate carcinoma and novel treatment strategies targetting these factors and their receptors. Insulin-like growth factor-I (IGF-I) and its primary receptor insulin-like growth factor receptor-I (IGF-IR) are among these factors. Biologic functions and role in malign progression are primarily achieved via IGF-IR which is a type 2 tyrosine kinase receptor. IGF-IR plays an important role in mitogenesis, angiogenesis, transformation, apoptosis and cell motility. It also generates intensive proliferative signals leading to carcinogenesis in prostate tissue. So IGF-IR and its associated signalling system have provoked considerable interest over recent years as a novel therapeutic target in cancer. In this paper it is aimed to sum up the lately published literature searching the relation of IGF-IR and prostate cancer in terms of incidence, pathologic features, and prognosis. This is followed by a discussion of the different possible targets within the IGF-1R system, and drugs developed to interact at each target. A systems-based approach is then used to review the in vitro and in vivo data in the published literature of the following compounds targeting IGF-1R components using specific examples: growth hormone releasing hormone antagonists (e.g. JV-1-38), growth hormone receptor antagonists (e.g. pegvisomant), IGF-1R antibodies (e.g. CP-751,871, AVE1642/EM164, IMC-A12, SCH-717454, BIIB022, AMG 479, MK-0646/h7C10), and IGF-1R tyrosine kinase inhibitors (e.g. BMS-536942, BMS-554417

  6. Rapid population growth.

    1972-01-01

    At the current rate of population growth, world population by 2000 is expected to reach 7 billion or more, with developing countries accounting for some 5.4 billion, and economically advanced nations accounting for 1.6 billion. 'Population explosion' is the result of falling mortality rates and continuing high birth rates. Many European countries, and Japan, have already completed what is termed as demographic transition, that is, birth rates have fallen to below 20 births per 1000 population, death rates to 10/1000 population, and annual growth rates are 1% or less; annual growth rates for less developed countries ranged from 2 to 3.5%. Less developed countries can be divided into 3 groups: 1) countries with both high birth and death rates; 2) countries with high birth rates and low death rates; and 3) countries with intermediate and declining birth rates and low death rates. Rapid population growth has serious economic consequences. It encourages inequities in income distribution; it limits rate of growth of gross national product by holding down level of savings and capital investments; it exerts pressure on agricultural production and land; and it creates unemployment problems. In addition, the quality of education for increasing number of chidren is adversely affected, as high proportions of children reduce the amount that can be spent for the education of each child out of the educational budget; the cost and adequacy of health and welfare services are affected in a similar way. Other serious consequences of rapid population growth are maternal death and illness, and physical and mental retardation of children of very poor families. It is very urgent that over a billion births be prevented in the next 30 years to reduce annual population growth rate from the current 2% to 1% per year.

  7. Population growth and consumption.

    Chalkley, K

    1997-04-01

    The relationship between population growth, resource consumption, and environmental degradation is complex. The rise in "greenhouse gases" that will cause climatic change is clearly due to human activity, and pollutants are often concentrated in densely populated areas. However, even an area with a negative population growth, such as Russia, can experience severe environmental degradation due to poor management. Consumption patterns have the most effect on ozone depletion, while population growth threatens biodiversity of and within species through the destruction of ecosystems. Migration joins population growth and social factors, such as land inequality, as major causes of deforestation, and global demand for water is expected to increase faster than the rate of population growth. Coastal development and over-fishing threaten to deplete the oceans, while soil quality is threatened by inappropriate land use. Estimates of the earth's carrying capacity range from less than 3 billion to more than 44 billion people, indicating how difficult it is to assess this figure. Development efforts throughout the world may lead to human gains that will ultimately be negated by environmental losses. These factors have led to growing support for environmentally sustainable development.

  8. The Growth Delusion

    Bob Lloyd

    2009-08-01

    Full Text Available Concern for the environment and a move towards “sustainable development” has assisted progress in a wide range of renewable energy technologies in recent years. The science suggests that a transition from fossil fuels to sustainable sources of energy in a time frame commensurate with the demise of the fossil fuels and prevention of runaway climate change is needed. However, while the movement towards sustainable energy technologies is underway, the World does not want to give up the idea of continuing economic growth. In recent times the financial collapse of October 2008 has given rise to yet another set of pleas from corporations and politicians alike to restart the growth machine. The transition to renewable energy technologies will be difficult to achieve as nowhere within existing economic and political frameworks are the limits to when growth will be curtailed being set. It is possible that the irrational insistence on endless growth as a non negotiable axiom, by a large proportion of the world’s population, may in fact be akin to the similarly irrational belief, by a similarly large proportion of the world’s population, that a supernatural being controls our existence and destiny. The irrationality of religion has recently been examined by Richard Dawkins in “The God Delusion”. Dawkins’ book is used as a starting point to investigate similarities between a belief in God and a belief in continuous growth.

  9. From Limits to Growth to Limitless Growth

    Garry Jacobs

    2012-04-01

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

  10. Experimental intrauterine growth retardation.

    van Marthens, E; Harel, S; Zamenshof, S

    1975-01-01

    The effects of experimental intrauterine growth retardation on subsequent fetal development, especially with respect to brain development, were studied in a new animal model. The rabbit was chosen since it has a perinatal pattern of brain development similar to that of the human. Experimental ischemia was induced during the last trimester by ligation of spiral arterioles and the differential effects on fetal development at term (30th gestational day) are reported. Specific brain regions were examined for wet weight, total cell number (DNA) and total protein content. Highly significant decreases in all these parameters were found in both the cortex and cerebellum following experimental intrauterine growth retardation; these two organs were differentially affected. The prospects and advantages of using this animal model for the study of the postnatal "catch-up growth" are discussed.

  11. Urban growth management

    Jørgensen, Gertrud; Alexander Sick Nielsen, Thomas; Grünfelder, Julien

    2011-01-01

    , and finally urban attractivity policies. Effective regional bodies are needed to deal with urban expansion and peri-urbanisation at a relevant scale; European rural and agricultural policies makes up the main ‘policy complex’ targeting the non-urban area including its land uses; while lastly leverage of urban...... urban growth and curb urban sprawl in a wider sense. Methodology The main methodology of the paper is a desk-research based review of policy options supplemented with field study and interviews in selected cased study regions. This paper consists of two parts. The first part is based on literature...... there are contradictions in the evidence presented in the literature, we believe that it may be safely said that urban growth management policies have an influence on urban growth under certain preconditions including: sufficient time for implementation and continuity of efforts; choice of appropriate policy measures...

  12. New microbial growth factor

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

    1977-01-01

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

  13. Moral Personality Growth

    Jana Kalin

    1998-12-01

    Full Text Available Learning in terms of personality growth is a life-long process, just as personality growth itself is a life-long process. Kalin presents a number of psychological theories and their impact on moral development - which is an integral part of personality growth. The paper further treats the formation and changing of beliefs, and the role of education in the two processes. Great emphasis is put on cognitive theories; Kalin explains those formulated by L. Kohlberg and J. Rest. In discussing the process of shaping and changing one's views, special emphasis is put on the environment, or rather the social group an individual belongs to, and on the influence of personality traits and experience. The paper juxtaposes the influence - strengths and weaknesses - of the psychology of persuasion and education on forming and changing one's views, taken into consideration that views consist of cognitive, emotive and conative dimensions.

  14. The double Laplacian growth

    Loutsenko, I.; Yermolayeva, O.

    2008-06-01

    The dynamics of the idealized Laplacian growth (or the Hele-Shaw problem) can be approximated by the Poiselle flow which in appropriate units takes the form of the Darcy law. In this paper we account for the liquid inertia in the Hele-Shaw problem at zero surface tension limit. The Laplace dynamics for the pressure is extended here with one more for the velocity potential for which we call this growth process the Double Laplacian. The application of the conformal mappings technique leads to doubled dynamics for both the conformal map and the complex potential, which is presented in the paper for the radial and the planar growth. We apply the stability analysis and discuss the integrability for the stated problem. (author)

  15. Recovery of pituitary-gonadal function in male and female rats after prolonged administration of a potent antagonist of luteinizing hormone-releasing hormone (SB-75).

    Bokser, L; Srkalovic, G; Szepeshazi, K; Schally, A V

    1991-08-01

    The reversibility of the antifertility effects induced by long-term administration of the LH-RH antagonistic analog [Ac-D-Nal(2)1, D-Phe(4Cl)2, D-Pal(3)3, D-Cit6, D-Ala10]-LH-RH (SB-75) was investigated in male and female rats. Male rats were implanted with osmotic minipumps releasing 50 micrograms of SB-75/day for 60 days. The control rats were implanted with minipumps containing only vehicle. The treatment with the antagonist caused a significant decrease in the weights of the testes, seminal vesicles and ventral prostates (p less than 0.01) and reduced serum LH and testosterone levels (p less than 0.01). The histology of the testes from the treated rats showed that spermatogenesis was totally depressed. No mature elongated or round spermatids were found in the seminiferous tubules, spermatocytes being the most advanced germ cell form in 100% of the testicular tubules. These changes indicate that a total spermatogenetic arrest occurred in the treated animals. Ninety days after cessation of treatment with the LH-RH antagonist, there was a complete recovery of the weights of the testes, seminal vesicles and ventral prostates and LH and testosterone returned to control levels. Histological studies revealed a complete recovery of spermatogenesis, with 99.2% of seminiferous tubules containing mature elongated spermatids. Immediately after the discontinuation of treatment with SB-75, a significant down-regulation of the pituitary LH-RH receptors was found, but 90 days later, this phenomenon was completely reversed. Female rats were injected every 3 weeks for 6 weeks with SB-75 microcapsules, at a dose calculated to release 27 micrograms/day of the antagonist. The treatment with SB-75 disrupted the normal estrous cycle. Body weights were not affected, but ovarian and uterine weights were significantly decreased (p less than 0.01 and p less than 0.05, respectively) in the animals treated with the antagonist. Treated rats had significantly lower LH (p less than 0.05) and estradiol (p less than 0.01) levels than controls. The histology of the ovaries from the SB-75-treated group showed that the ratio of small to large maturing follicles increased significantly (p less than 0.01) and corpora lutea were absent. Two months after the cessation of treatment, a complete recovery in the organ weights and in hormonal levels was observed and no histological differences were found between the ovaries in treated and untreated rats. These collective results indicate that the suppression of gonadal function induced by the treatment with LH-RH antagonist SB-75 is completely reversible both in male and female animals.(ABSTRACT TRUNCATED AT 400 WORDS)

  16. Receptors for luteinizing hormone-releasing hormone (LHRH) in benign prostatic hyperplasia (BPH) as potential molecular targets for therapy with LHRH antagonist cetrorelix.

    Rozsa, Bernadett; Nadji, Mehrdad; Schally, Andrew V; Dezso, Balazs; Flasko, Tibor; Toth, Gyorgy; Mile, Melinda; Block, Norman L; Halmos, Gabor

    2011-04-01

    The majority of men will develop symptoms of benign prostatic hyperplasia (BPH) after 70 years of age. Various studies indicate that antagonists of LHRH, such as cetrorelix, exert direct inhibitory effects on BPH mediated by specific LHRH receptors. Our aim was to investigate the mRNA for LHRH and LHRH receptors and the expression of LHRH receptors in specimens of human BPH. The expression of mRNA for LHRH (n=35) and LHRH receptors (n=55) was investigated by RT-PCR in surgical specimens of BPH, using specific primers. The characteristics of binding sites for LHRH on 20 samples were determined by ligand competition assays. The LHRH receptor expression was also examined in 64 BPH specimens by immunohistochemistry. PCR products for LHRH were found in 18 of 35 (51%) BPH tissues and mRNA for LHRH receptors was detected in 39 of 55 (71%) BPH specimens. Eighteen of 20 (90%) samples showed a single class of high affinity binding sites for [D-Trp(6) ]LHRH with a mean K(d) of 4.04 nM and a mean B(max) of 527.6 fmol/mg membrane protein. LHRH antagonist cetrorelix showed high affinity binding to LHRH receptors in BPH. Positive immunohistochemical reaction for LHRH receptors was present in 42 of 64 (67%) BPH specimens. A high incidence of LHRH receptors in BPH supports the use of LHRH antagonists such as cetrorelix, for treatment of patients with lower urinary tract symptoms from BPH. Copyright © 2010 Wiley-Liss, Inc.

  17. Effect of a hormone-releasing intrauterine system (Mirena® on aromatase and Cox-2 expression in patients with adenomyosis submitted or not, to endometrial resection

    Maia R

    2012-04-01

    Full Text Available Hugo Maia Jr1,2, Clarice Haddad1, Julio Casoy1, Rebeca Maia1, Nathanael Pinheiro3, Elsimar M Coutinho11Centro de Pesquisa e Assistência em Reprodução Humana (CEPARH, 2Itaigara Memorial Day Hospital, 3IMAGEPAT, Salvador, Bahia, BrazilObjective: To investigate the effect of a levonorgestrel-releasing intrauterine system (Mirena® on aromatase and cyclooxygenase-2 (Cox-2 expression in the endometrium of patients with adenomyosis who were submitted to endometrial resection at the time of insertion, compared to a group not submitted to endometrial resection and a group of controls with adenomyosis not submitted to any previous hormonal treatment.Patients and methods: Patients with adenomyosis (n = 89 were included in this study. Twenty-two patients had been using Mirena® for 5 years but had not been submitted to endometrial resection prior to insertion of the device. Twenty-four patients were submitted to endometrial resection at the time of Mirena® insertion. The remaining 43 patients with adenomyosis had undergone no previous hormonal treatment and served as a control group. Cox-2 and aromatase expression were determined in the endometrium by immunohistochemistry.Results: Use of Mirena® for 5 years reduced aromatase expression in the endometrium; however, this reduction was significantly greater in the uteri previously submitted to endometrial resection. The reduction in Cox-2 expression was significant only in the uteri submitted to endometrial resection followed by the insertion of Mirena®.Conclusion: Endometrial resection followed by the insertion of Mirena® was associated with greater rates of amenorrhea in patients with adenomyosis, which in turn were associated with a more effective inhibition of aromatase and Cox-2 expression in the endometrium.Keywords: aromatase, Mirena®, adenomyosis, Cox-2, endometrium, levonorgestrel

  18. Synaptology of luteinizing hormone-releasing hormone (LHRH)-immunoreactive cells in the nervus terminalis of the gray short-tailed opossum (Monodelphis domestica).

    Zheng, L M; Pfaff, D W; Schwanzel-Fukuda, M

    1990-05-08

    Light and electron microscopic immunocytochemistry were used to examine the structure of LHRH neurons and fibers in the nervus terminalis of the gray short-tailed opossum (Monodelphis domestica). LHRH-immunoreactive neurons and fibers form a loose plexus within the fascicular network of the ganglion terminale on the median surface of the olfactory bulb. There are at least two populations of LHRH-immunoreactive neurons within the network of the ganglion terminale: fusiform and round neurons similar to those described in the forebrain. At the ultrastructural level, axosomatic and axodendritic contacts were seen between LHRH-immunoreactive and nonimmunoreactive elements in the ganglion terminale. These contacts were classified as 1) synaptic input, with asymmetric synapses seen between a nonimmunoreactive axon terminal and a LHRH-immunoreactive cell body or a nonimmunoreactive axon terminal and a LHRH-immunoreactive dendritic process. 2) synaptic output, with symmetric synapses seen between LHRH-immunoreactive and nonimmunoreactive processes. This study is the first systematic examination of the ultrastructure of the LHRH-immunoreactive neurons and their synaptic contacts in the nervus terminalis. The possible integrative roles for this LHRH-immunoreactive system are discussed.

  19. Inhibition of sup 125 I organification and thyroid hormone release by interleukin-1, tumor necrosis factor-alpha, and interferon-gamma in human thyrocytes in suspension culture

    Sato, K.; Satoh, T.; Shizume, K.; Ozawa, M.; Han, D.C.; Imamura, H.; Tsushima, T.; Demura, H.; Kanaji, Y.; Ito, Y. (Institute of Clinical Endocrinology, Tokyo (Japan))

    1990-06-01

    To elucidate the mechanism of decreased 131I uptake by the thyroid gland in patients with subacute thyroiditis and painless thyroiditis, human thyroid follicles were cultured with interleukin-1 (IL-1), tumor necrosis factor-alpha (TNF alpha), and/or interferon-gamma (IFN gamma), and the effects of these cytokines on thyroid function were studied in vitro. When human thyrocytes were cultured in RPMI-1640 medium containing 0.5% fetal calf serum and TSH for 5-8 days, the cells incorporated 125I, synthesized de novo (125I)iodotyrosines and (125I)iodothyronines, and secreted (125I)T4 and (125I)T3 into the medium. IL-1 alpha and IL-1 beta inhibited 125I incorporation and (125I)iodothyronine release in a concentration-dependent manner. The minimal inhibitory effect was detected at 10 pg/ml. Electron microscopic examination revealed a marked decrease in lysosome formation in IL-1-treated thyrocytes. TNF alpha and IFN gamma also inhibited thyroid function in a concentration-dependent manner. Furthermore, when thyrocytes were cultured with IL-1, TNF alpha and IFN gamma, these cytokines more than additively inhibited thyroid function. Although the main mechanism of 131I uptake suppression in the thyroid gland in subacute thyroiditis is due to cellular damage and suppression of TSH release, our present findings suggest that IL-1, TNF alpha, and IFN gamma produced in the inflammatory process within the thyroid gland further inhibit iodine incorporation and at least partly account for the decreased 131I uptake by the thyroid gland in destruction-induced hyperthyroidism.

  20. The effect of luteinizing hormone releasing hormone (LH-RH) and estrogen on RNA synthesis in anterior pituitary and different brain regions of rats

    Biro, J.

    1978-01-01

    Estradiol-17beta caused a marked reduction of RNA content in the cortex, hippocampus, brain stem, hypothalamus and RNA synthesis in the pituitary. LH-RH had facilitatory effect on the cortical and inhibitory influence on the hypothalamic RNA synthesis in vitro, and suppressed the pituitary RNA synthesis both in vivo and in vitro. The possible regulatory role of the LH-RH in the nucleic acid metabolism is discussed. (author)

  1. Inhibition of 125I organification and thyroid hormone release by interleukin-1, tumor necrosis factor-alpha, and interferon-gamma in human thyrocytes in suspension culture

    Sato, K.; Satoh, T.; Shizume, K.; Ozawa, M.; Han, D.C.; Imamura, H.; Tsushima, T.; Demura, H.; Kanaji, Y.; Ito, Y.

    1990-01-01

    To elucidate the mechanism of decreased 131I uptake by the thyroid gland in patients with subacute thyroiditis and painless thyroiditis, human thyroid follicles were cultured with interleukin-1 (IL-1), tumor necrosis factor-alpha (TNF alpha), and/or interferon-gamma (IFN gamma), and the effects of these cytokines on thyroid function were studied in vitro. When human thyrocytes were cultured in RPMI-1640 medium containing 0.5% fetal calf serum and TSH for 5-8 days, the cells incorporated 125I, synthesized de novo [125I]iodotyrosines and [125I]iodothyronines, and secreted [125I]T4 and [125I]T3 into the medium. IL-1 alpha and IL-1 beta inhibited 125I incorporation and [125I]iodothyronine release in a concentration-dependent manner. The minimal inhibitory effect was detected at 10 pg/ml. Electron microscopic examination revealed a marked decrease in lysosome formation in IL-1-treated thyrocytes. TNF alpha and IFN gamma also inhibited thyroid function in a concentration-dependent manner. Furthermore, when thyrocytes were cultured with IL-1, TNF alpha and IFN gamma, these cytokines more than additively inhibited thyroid function. Although the main mechanism of 131I uptake suppression in the thyroid gland in subacute thyroiditis is due to cellular damage and suppression of TSH release, our present findings suggest that IL-1, TNF alpha, and IFN gamma produced in the inflammatory process within the thyroid gland further inhibit iodine incorporation and at least partly account for the decreased 131I uptake by the thyroid gland in destruction-induced hyperthyroidism

  2. Stochastic ontogenetic growth model

    West, B. J.; West, D.

    2012-02-01

    An ontogenetic growth model (OGM) for a thermodynamically closed system is generalized to satisfy both the first and second law of thermodynamics. The hypothesized stochastic ontogenetic growth model (SOGM) is shown to entail the interspecies allometry relation by explicitly averaging the basal metabolic rate and the total body mass over the steady-state probability density for the total body mass (TBM). This is the first derivation of the interspecies metabolic allometric relation from a dynamical model and the asymptotic steady-state distribution of the TBM is fit to data and shown to be inverse power law.

  3. Time for Growth

    Boerner, Lars; Severgnini, Battista

    This paper studies the impact of the early adoption of one of the most important high-technology machines in history, the public mechanical clock, on long-run growth in Europe. We avoid endogeneity by considering the relationship between the adoption of clocks with two sets of instruments: distance...... from the first adopters and the appearance of repeated solar eclipses. The latter instrument is motivated by the predecessor technologies of mechanical clocks, astronomic instruments that measured the course of heavenly bodies. We find significant growth rates between 1500 and 1700 in the range of 30...

  4. Inequality, Tolerance, and Growth

    Bjørnskov, Christian

    This paper argues for the importance of individuals' tolerance of inequality for economic growth. By using the political ideology of governments as a measure of revealed tolerance of inequality, the paper shows that controlling for ideology improves the accuracy with which the effects of inequality...... are measured. Results show that inequality reduces growth but more so in societies where people perceive it as being relatively unfair. Further results indicate that legal quality and social trust are likely transmission channels for the effects of inequality....

  5. Inequality, Tolerance, and Growth

    Bjørnskov, Christian

    2004-01-01

    This paper argues for the importance of individuals' tolerance of inequality for economic growth. By using the political ideology of governments as a measure of revealed tolerance of inequality, the paper shows that controlling for ideology improves the accuracy with which the effects of inequality...... are measured. Results show that inequality reduces growth but more so in societies where people perceive it as being relatively unfair. Further results indicate that legal quality and social trust are likely transmission channels for the effects of inequality....

  6. Gaussian radial growth

    Jónsdóttir, Kristjana Ýr; Jensen, Eva B. Vedel

    The growth of planar and spatial objects is often modelled using one-dimensional size parameters, e.g. volume, area or average radius. We take a more detailed approach and model how the boundary of a growing object expands in time. We mainly consider star-shaped planar objects. The model can...... be regarded as a dynamic deformable template model. The limiting shape of the object may be circular but this is only one possibility among a range of limiting shapes. An application to tumour growth is presented. Two extensions of the model, involving time series and Lévy bases, respectively, are briefly...

  7. Intrauterine growth restriction

    Bernardita Donoso Bernales

    2012-07-01

    Full Text Available It is estimated that the true prevalence of intrauterine growth restriction is 3-10% of all pregnancies, making this fetal condition one of the most frequent obstetric problems, together with premature labor and premature rupture of membranes. The article stresses the importance of early diagnosis because of the associated risks.

  8. Crystal growth and doping

    Paorici, C.

    1980-01-01

    Section 1 contains a self-consistent review of the basic growth features. After a short introduction concerning the driving force acting in a crystallization process, three main topics are broadly discussed: (i) interface kinetics; (ii) transport kinetics, and (iii) growth stability conditions. On point (i), after definition of the nature of interface, using Temkin's model, the growth mechanisms predicted by Burton, Cabrera and Frank (BCF) and bidimensional nucleation theories are fully developed. On points (ii) and (iii), the differential equations of the constitutional (concentration) and thermal fields are presented and discussed in terms of relevant approximations, suitable boundary conditions and limit values expected in order to have growth stability. Section 2 reports various experimental procedures for growing bulk crystals from the melt, from solutions and from the vapour phase. The basic concepts of Section 1 are amply employed for a critical discussion of possibilities, advantages and drawbacks of the methods described. Along the same lines, in Section 3 the principal epitaxial deposition procedures are highlighted. Section 4 contains a brief account of doping and of stoichiometry-defect control procedures. There is a long, carefully chosen list of bibliographical references. (author)

  9. [Growth of the neurocranium].

    Hodacová, Z; Skalská, H

    1998-01-01

    The present study demonstrates the results of evaluation of growth changes of the neurocranium in a set of 98 human skulls of immature individuals aged 6-18/20/ years from the XIII.-XVIII. century. Craniometric values were matched with the corresponding values measured on the skulls of the same age groups from the IX. century and IX.-XII. centuries.

  10. Carboxydotrophic growth of

    Geelhoed, J.; Henstra, A.M.; Stams, A.J.M.

    2016-01-01

    This study shows that Geobacter sulfurreducensgrows on carbon monoxide (CO) as electron donor with fumarateas electron acceptor. Geobacter sulfurreducens wastolerant to high CO levels, with up to 150 kPa in the headspacetested. During growth, hydrogen was detected in very slightamounts (~5 Pa). In

  11. Economic Growth Models Transition

    Coralia Angelescu

    2006-03-01

    Full Text Available The transitional recession in countries of Eastern Europe has been much longer than expected. The legacy and recent policy mistakes have both contributed to the slow progress. As structural reforms and gradual institution building have taken hold, the post-socialist economics have started to recover, with some leading countries building momentum toward faster growth. There is a possibility that in wider context of globalization several of these emerging market economies will be able to catch up with the more advanced industrial economies in a matter of one or two generations. Over the past few years, most candidate countries have made progress in the transition to a competitive market economy, macroeconomic stabilization and structural reform. However their income levels have remained far below those in the Member States. Measured by per capita income in purchasing power standards, there has been a very limited amount of catching up over the past fourteen years. Prior, the distinctions between Solow-Swan model and endogenous growth model. The interdependence between transition and integration are stated in this study. Finally, some measures of macroeconomic policy for sustainable growth are proposed in correlation with real macroeconomic situation of the Romanian economy. Our study would be considered the real convergence for the Romanian economy and the recommendations for the adequate policies to achieve a fast real convergence and sustainable growth.

  12. Economic Growth Models Transition

    Coralia Angelescu

    2006-01-01

    Full Text Available The transitional recession in countries of Eastern Europe has been much longer than expected. The legacy and recent policy mistakes have both contributed to the slow progress. As structural reforms and gradual institution building have taken hold, the post-socialist economics have started to recover, with some leading countries building momentum toward faster growth. There is a possibility that in wider context of globalization several of these emerging market economies will be able to catch up with the more advanced industrial economies in a matter of one or two generations. Over the past few years, most candidate countries have made progress in the transition to a competitive market economy, macroeconomic stabilization and structural reform. However their income levels have remained far below those in the Member States. Measured by per capita income in purchasing power standards, there has been a very limited amount of catching up over the past fourteen years. Prior, the distinctions between Solow-Swan model and endogenous growth model. The interdependence between transition and integration are stated in this study. Finally, some measures of macroeconomic policy for sustainable growth are proposed in correlation with real macroeconomic situation of the Romanian economy. Our study would be considered the real convergence for the Romanian economy and the recommendations for the adequate policies to achieve a fast real convergence and sustainable growth.

  13. Aid, Growth, and Development

    Arndt, Channing; Jones, Edward Samuel; Tarp, Finn

    ) ability to pay, and (iv) level of interaction with public officials. Moreover, when informal firms become formal the probability of paying bribes increases. Becoming formal is also associated with a revenue growth premium that is not driven by self-selection of well-performing firms. On average...

  14. Fibroblast growth factor 23

    Dr Olaleye

    Systemic phosphate homeostasis is maintained through several hormonal mechanisms which involve fibroblast growth factor 23 (FGF-23), α-klotho, vitamin D and parathyroid hormone. FGF-23 is known to be the major regulator of phosphate balance (Mirams et al., 2004). FGF-23 is a phosphaturic hormone, which is.

  15. Perspectives on population growth.

    1996-09-01

    Assume that everyone has the same information on population growth. There are many different opinions on what that information means and what should be done about it. Some people worry about current rates of growth, especially in the context of growing per capita consumption, and believe that all reasonable steps should be taken to reduce rates and stabilize population size. Others believe that growing populations can be accommodated by reducing consumption in rich countries, that technological progress will supply the new resources needed, that the development needed to support a larger population can be sustained, that large population size fosters prosperity, or that birth rates are falling and current growth is just temporary. These are all valid positions worthy of at least debate. Interest groups commonly acknowledgement population growth as a significant issue, but offer no response to it. Sometimes the issue goes unrecognized because it conflicts with a more highly valued personal agenda item. Finally, some responses come from confusion and anger rather than reasoning or self-interest. The proponents of these latter arguments bring nothing constructive to the debate.

  16. Consumption growth accounting

    Dietzenbacher, Erik; de Groot, Olaf J.; Los, Bart

    The methodology in this paper combines an input-output structural decomposition approach with the supply-side perspective of mainstream growth accounting. In explaining the intertemporal change in consumption per worker, three sets of effects are distinguished. First, contributions due to several

  17. Global Green Growth Institute

    Müller, Anders Riel

    2017-01-01

    Har man fulgt historien om Venstres gruppeformand Lars Løkkes rejser på 1. klasse i forbindelse med formandsposten for Global Green Growth Institute (GGGI) er der sikkert nogle der undrer sig over, hvad GGGI er for en størrelse. Medierne præsenterer GGGI som en international klimaorganisation, der...

  18. Geometrical approach to tumor growth

    Escudero, Carlos

    2006-01-01

    Tumor growth has a number of features in common with a physical process known as molecular beam epitaxy. Both growth processes are characterized by the constraint of growth development to the body border, and surface diffusion of cells/particles at the growing edge. However, tumor growth implies an approximate spherical symmetry that makes necessary a geometrical treatment of the growth equations. The basic model was introduced in a former article [C. Escudero, Phys. Rev. E 73, 020902(R) (200...

  19. Epidermal growth factor and growth in vivo

    Rhodes, J.A.

    1986-01-01

    Epidermal growth factor (EGF) causes a dose-dependent thickening of the epidermis in suckling mice. The cellular mechanisms underlying this thickening were analyzed by measuring the effect of EGF on the cell-cycle. Neonatal mice were given daily injections of either 2ug EGF/g body weight/day or an equivalent volume of saline, and on the seventh day received a single injection of 3 H-thymidine. At various times the mice were perfused with fixative; 1um sections of skin were stained with a modification of Harris' hematoxylin and were autoradiographed. The sections were analyzed using three methods based on the dependence on time after injection of 3 H-thymidine of: frequency of labelled mitoses, labelling index, and reciprocal grains/nucleus. It was found that EGF caused a two-fold increase in the cell production rate. The effect of exogenous EGF on the morphology of gastric mucosa and incisors of suckling mice was also studied. The gastric mucosa appeared thicker in EGF-treated animals, but the effect was not statistically significant. In contrast to its effect on epidermis and gastric mucosa, EGF caused a significant, dose-dependent decrease in the size of the incisors. Because the mouse submandibular salivary gland is the major source of EGF the effect of sialoadenectomy on female reproductive functions was examined. Ablation of the submandibular gland had no effect on: length of estrus cycle, ability of the female to produce litters, length of the gestation period, litter size, and weight of the litter at birth. There was also no effect on survival of the offspring or on age at which the eyelids separated

  20. Unsustainable growth, unsustainable capitalism

    Næss, Petter

    2006-01-01

    problems, but serve to further highlight the difficulties of changing capitalism towards sustainability. In a profit-oriented economy, capital accumulation is a prime driving force, and non-growth for the economy at large tends to result in serious economic and social crises. On the other hand, a de...... according to which the powers and mechanisms of the natural world are considered totally controllable by humans as if they were mere epiphenomena of the human world. On the other hand, the assumptions of certain ecological economists about the possibility of steady-state capitalism disregard the relation...... between capital and surplus value, which constitutes a strong mechanism driving the capitalist economy toward limitless growth....

  1. Growth and Poverty

    Arndt, Channing; Leyaro, Vincent; Mahrt, Kristi

    2017-01-01

    This chapter considers the evolution of welfare of the Tanzanian population using a multi-dimensional approach. It also employs a detailed economy-wide model of the Tanzanian economy to explore growth and monetary poverty reduction scenarios from 2007 to 2015. This approach permits assessment...... of the coherence of observed trends in macroeconomic variables and projects consumption poverty outcomes to 2015. In the multi-dimensional approach, we find that real gains have been achieved. On monetary poverty, our model broadly reproduces key macroeconomic features of the past eight years. We find...... that published consumption poverty reductions for 2007 to 2011/12 from the most recent assessment fall within a reasonable to optimistic range. And, the simulations generate broader based growth across the income distribution compared with the recent assessment. Looking forward, the simulations from 2012 to 2105...

  2. Old-growth Policy

    Diane Vosick

    2007-12-01

    Full Text Available Most federal legislation and policies (e.g., the Wilderness Act, Endangered Species Act, National Forest Management Act fail to speak directly to the need for old-growth protection, recruitment, and restoration on federal lands. Various policy and attitudinal barriers must be changed to move beyond the current situation. For example, in order to achieve the goal of healthy old growth in frequent-fire forests, the public must be educated regarding the evolutionary nature of these ecosystems and persuaded that collaborative action rather than preservation and litigation is the best course for the future of these forests. Land managers and policy makers must be encouraged to look beyond the single-species management paradigm toward managing natural processes, such as fire, so that ecosystems fall within the natural range of variability. They must also see that, given their recent evidence of catastrophic fires, management must take place outside the wildland-urban interface in order to protect old-growth forest attributes and human infrastructure. This means that, in some wilderness areas, management may be required. Land managers, researchers, and policy makers will also have to agree on a definition of old growth in frequent-fire landscapes; simply adopting a definition from the mesic Pacific Northwest will not work. Moreover, the culture within the federal agencies needs revamping to allow for more innovation, especially in terms of tree thinning and wildland fire use. Funding for comprehensive restoration treatments needs to be increased, and monitoring of the Healthy Forest Initiative and Healthy Forest Restoration Act must be undertaken.

  3. Analyzing growth trajectories

    McKeague, I. W.; López-Pintado, S.; Hallin, M.; Šiman, Miroslav

    2011-01-01

    Roč. 2, č. 6 (2011), s. 322-329 ISSN 2040-1744 R&D Projects: GA MŠk(CZ) 1M06047 Institutional research plan: CEZ:AV0Z10750506 Keywords : data depth contours * growth curves * nonparametric Bayes Subject RIV: BB - Applied Statistics, Operational Research Impact factor: 1.556, year: 2011 http://library.utia.cas.cz/separaty/2011/SI/siman-0376411.pdf

  4. Globalization, Growth and Poverty

    One-pagers are a publication of IDRC's “Globalization, Growth and Poverty” Program Initiative, ... was among the largest in the world, at 90 percent of the entire value of ... the workforce—including young adults, women, and the elderly who are ... UN ECLAC, 2010. 0. 1. 2. 3. 4. 5. 0. 10. 20. 30. 40. 50. 60. 70. 80. 90+. C o n.

  5. Valuation relationships under growth

    Benavides Franco, Julián

    2003-01-01

    One of the most important topics on valuation is the appropriate relationships between cash flows and rate of returns. I review those relationships under the premise, by Myers (1974), of the cost of debt as the right discount for the tax shield. Different hypotheses have been advanced for the tax shield risk, each one producing different valuation results, especially when growth is present. The consequences of some common mistakes on valuation are explored. One difference between the results ...

  6. DETERMINANTS OF ECONOMIC GROWTH

    Bartosz Totleben

    2013-01-01

    The article is examines the impact of macroeconomic indicators, in particular: human capital, government spending, innovation, political and social stability, on economic growth. In total 12 different indicators describing the economical, political and social conditions are taken into account. The study considers 102 countries between years 1960 and 2012 and two methods of estimation are performed: generalized method of moments (GMM) and fixed effects (FE). The results show the positive impac...

  7. Geography, Depreciation, and Growth

    Solomon M. Hsiang; Amir S. Jina

    2015-01-01

    It has been proposed that geography influences economic growth for many reasons. Previous analyses of comparative development seem to have sidestepped the question of location-dependent depreciation. However the construction of new measures of tropical cyclone exposure enables us to consider the potential impact of this single source of capital depreciation. Using an estimate of asset destruction due to tropical cyclones, we identify the "sandcastle depreciation" rate, and find support for lo...

  8. Can Growth Be Green?

    Gough, Ian

    2015-01-01

    This short article, based on a presentation at the London School of Economics, criticizes the common opinion that "green growth" offers a relatively painless - some even say pain-free - transition path for capitalist economies. After a brief summary of the daunting arithmetic entailed in combining fast decarbonization with continuing growth, the article advances 3 propositions. First, market-based carbon mitigation programs, such as carbon trading, cannot be sufficient and must be coupled with other policy pillars that foster transformative investment and widespread regulation. Second, a political economy of climate policy needs to draw on the lessons of comparative social policy research, which emphasizes the role of international pressures, interests, institutions, and ideas. Taking these into account gives a more realistic perspective on climate policy making in today's neoliberal world. Third, more radical policies on both consumption and production are called for, to ensure that carbon mitigation is not pursued at the expense of equity and social welfare. These include policies to restrain high-carbon luxury consumption and a transition toward shorter paid working time. The conclusion is that a realistic program of green growth will be immensely difficult and entail radical political change. © SAGE Publications 2015.

  9. Facilitating post traumatic growth

    Cox Helen

    2004-07-01

    Full Text Available Abstract Background Whilst negative responses to traumatic injury have been well documented in the literature, there is a small but growing body of work that identifies posttraumatic growth as a salient feature of this experience. We contribute to this discourse by reporting on the experiences of 13 individuals who were traumatically injured, had undergone extensive rehabilitation and were discharged from formal care. All participants were injured through involvement in a motor vehicle accident, with the exception of one, who was injured through falling off the roof of a house. Methods In this qualitative study, we used an audio-taped in-depth interview with each participant as the means of data collection. Interviews were transcribed verbatim and analysed thematically to determine the participants' unique perspectives on the experience of recovery from traumatic injury. In reporting the findings, all participants' were given a pseudonym to assure their anonymity. Results Most participants indicated that their involvement in a traumatic occurrence was a springboard for growth that enabled them to develop new perspectives on life and living. Conclusion There are a number of contributions that health providers may make to the recovery of individuals who have been traumatically injured to assist them to develop new views of vulnerability and strength, make changes in relationships, and facilitate philosophical, physical and spiritual growth.

  10. Crystal Growth Technology

    Scheel, Hans J.; Fukuda, Tsuguo

    2004-06-01

    This volume deals with the technologies of crystal fabrication, of crystal machining, and of epilayer production and is the first book on industrial and scientific aspects of crystal and layer production. The major industrial crystals are treated: Si, GaAs, GaP, InP, CdTe, sapphire, oxide and halide scintillator crystals, crystals for optical, piezoelectric and microwave applications and more. Contains 29 contributions from leading crystal technologists covering the following topics: General aspects of crystal growth technology Silicon Compound semiconductors Oxides and halides Crystal machining Epitaxy and layer deposition Scientific and technological problems of production and machining of industrial crystals are discussed by top experts, most of them from the major growth industries and crystal growth centers. In addition, it will be useful for the users of crystals, for teachers and graduate students in materials sciences, in electronic and other functional materials, chemical and metallurgical engineering, micro-and optoelectronics including nanotechnology, mechanical engineering and precision-machining, microtechnology, and in solid-state sciences.

  11. [Hormones and hair growth].

    Trüeb, R M

    2010-06-01

    With respect to the relationship between hormones and hair growth, the role of androgens for androgenetic alopecia (AGA) and hirsutism is best acknowledged. Accordingly, therapeutic strategies that intervene in androgen metabolism have been successfully developed for treatment of these conditions. Clinical observations of hair conditions involving hormones beyond the androgen horizon have determined their role in regulation of hair growth: estrogens, prolactin, thyroid hormone, cortisone, growth hormone (GH), and melatonin. Primary GH resistance is characterized by thin hair, while acromegaly may cause hypertrichosis. Hyperprolactinemia may cause hair loss and hirsutism. Partial synchronization of the hair cycle in anagen during late pregnancy points to an estrogen effect, while aromatase inhibitors cause hair loss. Hair loss in a causal relationship to thyroid disorders is well documented. In contrast to AGA, senescent alopecia affects the hair in a diffuse manner. The question arises, whether the hypothesis that a causal relationship exists between the age-related reduction of circulating hormones and organ function also applies to hair and the aging of hair.

  12. Multiple growth regimes: Insights from unified growth theory

    Galor, Oded

    2007-01-01

    Unified Growth Theory uncovers the forces that contributed to the existence of multiple growth regimes and the emergence of convergence clubs. It suggests that differential timing of take-offs from stagnation to growth segmented economies into three fundamental regimes: slow growing economies in a Malthusian regime, fast growing countries in a sustained growth regime, and economies in the transition between these regimes. In contrast to existing research that links regime switching thresholds...

  13. Gambling on growth.

    Feeney, A

    1990-01-01

    When the assumption is made that economic growth must be increased by 10% to accommodate population increases and to reduce poverty, the question is raised as to whether or not sustainable development is possible. The human population increased 3 times since 1900, and global economic activity has increased 7 times faster than population. Use of fossil fuels has increased by 30 times, and industrial production has increased by 50 times. The by-products of population growth and economic activity are loss of tropical rainforests; species extinction; desertification in Africa, India, and the US; toxic and radioactive pollution; and greenhouse warming and ozone depletion. The atmosphere's stability and human habitation is threatened. Sustainable development, as defined by the World Commission on Environment and Development (WCED) in "Our Common Future," is meeting present needs but not at the expense of future needs. Economic growth must proceed at different rates in different countries to close the gap between the rich and poor. Economic expansion has been criticized by the president of Negative Population Growth and the Environmental Defense Fund's coordinator of reform for the World Bank's environmental policies and Third World countries. US government response during the Reagan administration has been indifference, while support has come from the World Resources Institute, the Worldwatch Institute, the US National Wildlife Federation, and the Population Reference Bureau. Recent support has come from signers of the "G-7 Summit" and from IBM and the Dow Chemical Company. A few shared tenets are 1) that economic development is not sustainable, 2) environmental reforms are necessary to make development sustainable, 3) a trade-off is needed to increase Third World energy use, and 4) population must be stabilized. Many proposals have been offered including reducing population to 2 billion, or 40% of the current level. Reducing poverty globally is an environmentally sound

  14. Growth arrest despite growth hormone replacement, post-craniopharyngioma surgery.

    DeVile, C J; Hayward, R D; Neville, B G; Grant, D B; Stanhope, R

    1995-01-01

    Children with growth failure, whether secondary to an endocrinopathy such as growth hormone deficiency or secondary to neurological handicap with poor nutrient intake, grow at a subnormal rate but it is most unusual for a child to have complete growth arrest. PMID:7745571

  15. Growth throughout childhood of children born growth restricted

    Beukers, Fenny; Rotteveel, Joost; van Weissenbruch, Mirjam M.; Ganzevoort, Wessel; van Goudoever, Johannes B.; van Wassenaer-Leemhuis, Aleid G.

    2017-01-01

    Many studies that examine growth in growth-restricted children at birth do not discriminate between fetal growth restriction (FGR) and small for gestational age (SGA). These terms however are not synonymous. In SGA, stunting and increased weight gain have been reported. We do not know if this holds

  16. Entrepreneurial Diversity and Economic Growth

    I. Verheul (Ingrid); A.J. van Stel (André)

    2007-01-01

    textabstractMost studies investigating the relationship between entrepreneurship and economic growth treat entrepreneurs as a homogeneous group. This study investigates the impact of entrepreneurial diversity on national economic growth. Using data for 36 countries participating in the Global

  17. Market Acceptance of Smart Growth

    This report finds that smart growth developments enjoy market acceptance because of stability in prices over time. Housing resales in smart growth developments often have greater appreciation than their conventional suburban counterparts.

  18. Your Baby's Growth: 12 Months

    ... Safe Videos for Educators Search English Español Your Baby's Growth: 12 Months KidsHealth / For Parents / Your Baby's ... doubled his or her birth weight. Is My Baby Growing Normally? Babies' growth begins to slow as ...

  19. Tax Havens, Growth, and Welfare

    Chu, Hsun; Lai, Ching-Chong; Cheng, Chu-Chuan

    2013-01-01

    This paper develops an endogenous growth model featuring tax havens, and uses it to examine how the existence of tax havens affects the economic growth rate and social welfare in high-tax countries. We show that the presence of tax havens generates two conflicting channels in determining the growth effect. First, the public investment effect states that tax havens may erode tax revenues and in turn decrease the government’s infrastructure expenditure, thereby reducing growth. Second, the t...

  20. Corporate Stability and Economic Growth

    He, Kathy S.; Morck, Randall; Yeung, Bernard

    2003-01-01

    Greater instability in a country's list of top corporations is associated with faster economic growth. This faster growth is primarily due to faster growth in total factor productivity in industrialized countries, and faster capital accumulation in developing countries. These findings are consistent with the view that economic growth is more closely tied to the rise of new large firms than to the prosperity of established large firms. Although a stable list of leading corporations is highly c...

  1. The poverty elasticity of growth

    Heltberg, Rasmus

    2002-01-01

    How much does economic growth contribute to poverty reduction? I discuss analytical and empirical approches to assess the poverty elasticity of growth, and emphasize that the relationship between growth and poverty change is non-constant. For a given poverty measure, it depends on initial inequality and on the location of the poverty line relative to mean income. In most cases, growth is more important for poverty reduction than changes in inequality, but this does not tender inequality unimp...

  2. Economic growth and business cycles

    Canton, E.J.F.

    1997-01-01

    This thesis contains five essays on economic growth and business cycles. The main focus is on the interaction between economic growth and the cycle: is cyclical variability good or bad for the long-run rate of economic growth? The introduction aims to provide some empirical evidence for an

  3. PUBLIC GOODS, CORRUPTION AND GROWTH???

    Ratbek Dzhumashev

    2006-01-01

    In this paper, we analyse implications of corruption on growth. We extend existing growth models by incorporating ubiquitous corruption as a by-product of the public sector. Corruption affects both taxation and public good provision, and therefore causes income redistribution and inefficiencies in the public sector. These effects of corruption lead to lower growth through distortions of investment incentives and resources allocation.

  4. Advanced dendritic web growth development

    Hopkins, R. H.

    1985-01-01

    A program to develop the technology of the silicon dendritic web ribbon growth process is examined. The effort is being concentrated on the area rate and quality requirements necessary to meet the JPL/DOE goals for terrestrial PV applications. Closed loop web growth system development and stress reduction for high area rate growth is considered.

  5. Regulators of growth plate maturation

    Emons, Joyce Adriana Mathilde

    2010-01-01

    Estrogen is known to play an important role in longitudinal bone growth and growth plate maturation, but the mechanism by which estrogens exert their effect is not fully understood. In this thesis this role is further explored. Chapter 1 contains a general introduction to longitudinal bone growth

  6. Development and validation of a bioanalytical LC-MS method for the quantification of GHRP-6 in human plasma.

    Gil, Jeovanis; Cabrales, Ania; Reyes, Osvaldo; Morera, Vivian; Betancourt, Lázaro; Sánchez, Aniel; García, Gerardo; Moya, Galina; Padrón, Gabriel; Besada, Vladimir; González, Luis Javier

    2012-02-23

    Growth hormone-releasing peptide 6 (GHRP-6, His-(DTrp)-Ala-Trp-(DPhe)-Lys-NH₂, MW=872.44 Da) is a potent growth hormone secretagogue that exhibits a cytoprotective effect, maintaining tissue viability during acute ischemia/reperfusion episodes in different organs like small bowel, liver and kidneys. In the present work a quantitative method to analyze GHRP-6 in human plasma was developed and fully validated following FDA guidelines. The method uses an internal standard (IS) of GHRP-6 with ¹³C-labeled Alanine for quantification. Sample processing includes a precipitation step with cold acetone to remove the most abundant plasma proteins, recovering the GHRP-6 peptide with a high yield. Quantification was achieved by LC-MS in positive full scan mode in a Q-Tof mass spectrometer. The sensitivity of the method was evaluated, establishing the lower limit of quantification at 5 ng/mL and a range for the calibration curve from 5 ng/mL to 50 ng/mL. A dilution integrity test was performed to analyze samples at higher concentration of GHRP-6. The validation process involved five calibration curves and the analysis of quality control samples to determine accuracy and precision. The calibration curves showed R² higher than 0.988. The stability of the analyte and its internal standard (IS) was demonstrated in all conditions the samples would experience in a real time analyses. This method was applied to the quantification of GHRP-6 in plasma from nine healthy volunteers participating in a phase I clinical trial. Copyright © 2011 Elsevier B.V. All rights reserved.

  7. Evidence Supporting a Role for Constitutive Ghrelin Receptor Signaling in Fasting-Induced Hyperphagia in Male Mice.

    Fernandez, Gimena; Cabral, Agustina; Andreoli, María F; Labarthe, Alexandra; M'Kadmi, Céline; Ramos, Jorge G; Marie, Jacky; Fehrentz, Jean-Alain; Epelbaum, Jacques; Tolle, Virginie; Perello, Mario

    2018-02-01

    Ghrelin is a potent orexigenic peptide hormone that acts through the growth hormone secretagogue receptor (GHSR), a G protein-coupled receptor highly expressed in the hypothalamus. In vitro studies have shown that GHSR displays a high constitutive activity, whose physiological relevance is uncertain. As GHSR gene expression in the hypothalamus is known to increase in fasting conditions, we tested the hypothesis that constitutive GHSR activity at the hypothalamic level drives the fasting-induced hyperphagia. We found that refed wild-type (WT) mice displayed a robust hyperphagia that continued for 5 days after refeeding and changed their food intake daily pattern. Fasted WT mice showed an increase in plasma ghrelin levels, as well as in GHSR expression levels and ghrelin binding sites in the hypothalamic arcuate nucleus. When fasting-refeeding responses were evaluated in ghrelin- or GHSR-deficient mice, only the latter displayed an ∼15% smaller hyperphagia, compared with WT mice. Finally, fasting-induced hyperphagia of WT mice was significantly smaller in mice centrally treated with the GHSR inverse agonist K-(D-1-Nal)-FwLL-NH2, compared with mice treated with vehicle, whereas it was unaffected in mice centrally treated with the GHSR antagonists D-Lys3-growth hormone-releasing peptide 6 or JMV2959. Taken together, genetic models and pharmacological results support the notion that constitutive GHSR activity modulates the magnitude of the compensatory hyperphagia triggered by fasting. Thus, the hypothalamic GHSR signaling system could affect the set point of daily food intake, independently of plasma ghrelin levels, in situations of negative energy balance. Copyright © 2018 Endocrine Society.

  8. Great growth debate: an argument for rational growth policies

    Bond, E; Koven, A

    1978-05-01

    The argument for rational growth policies in Canada advocates an expanding economy as the only one able to compensate both winners and losers. A constant growth rate--whether it is positive, negative, or zero--cannot work. A desirable growth rate must be flexible in the long term, which means that policies for zero growth must select only parts of the economy. On one hand, the creation of aritifical needs by advertising, urban expansion, and demographic growth in over-populated countries should be halted. On the other hand, we must expand necessary human welfare services. Zero growth does not mean that we must go back to poverty, asceticism, and constraint. An optimum growth policy will aim for moderation in all things. (Abstract, edited)

  9. Growth hormone in intra-uterine growth retarded newborns.

    Setia, Sajita; Sridhar, M G; Bhat, Vishnu; Chaturvedula, Latha

    2007-11-01

    To study growth hormone levels in IUGR and healthy controls and its association with birth weight and ponderal index. We studied 50 Intra uterine growth retarded (IUGR) and 50 healthy newborns born at term by vaginal delivery in JIPMER, Pondicherry, India. Cord blood was collected at the time of delivery for measurement of growth hormone. When compared with healthy newborns, IUGR newborns had higher growth hormone levels (mean +/- SD, 23.5 +/- 15.6 vs 16.2 +/- 7.61 ngm/ml, P = 0.019). A negative correlation was identified between growth hormone levels and birth weight (r2 = - 0.22, P = 0.03) and ponderal index (r2 = - 0.36, P = 0.008). Correlation of growth hormone levels was much more confident with ponderal index than with birth weight. At birth IUGR infants display increased growth hormone levels which correlate with ponderal index much more confidently than with birth weight.

  10. Biofuels, poverty, and growth

    Arndt, Channing; Benfica, Rui; Tarp, Finn

    2010-01-01

    and accrual of land rents to smallholders, compared with the more capital-intensive plantation approach. Moreover, the benefits of outgrower schemes are enhanced if they result in technology spillovers to other crops. These results should not be taken as a green light for unrestrained biofuels development...... Mozambique's annual economic growth by 0.6 percentage points and reduces the incidence of poverty by about 6 percentage points over a 12-year phase-in period. Benefits depend on production technology. An outgrower approach to producing biofuels is more pro-poor, due to the greater use of unskilled labor...

  11. Aid and sectoral growth

    Selaya, Pablo; Thiele, Rainer

    2010-01-01

    This article examines empirically the proposition that aid to poor countries is detrimental for external competitiveness, giving rise to Dutch disease type effects. At the aggregate level, aid is found to have a positive effect on growth. A sectoral decomposition shows that the effect is (i......) significant and positive in the tradable and the nontradable sectors, and (ii) equally strong in both sectors. The article thus provides no empirical support for the hypothesis that aid reduces external competitiveness in developing countries. A possible reason for this finding is the existence of large idle...

  12. Modeling urban fire growth

    Waterman, T.E.; Takata, A.N.

    1983-01-01

    The IITRI Urban Fire Spread Model as well as others of similar vintage were constrained by computer size and running costs such that many approximations/generalizations were introduced to reduce program complexity and data storage requirements. Simplifications were introduced both in input data and in fire growth and spread calculations. Modern computational capabilities offer the means to introduce greater detail and to examine its practical significance on urban fire predictions. Selected portions of the model are described as presently configured, and potential modifications are discussed. A single tract model is hypothesized which permits the importance of various model details to be assessed, and, other model applications are identified

  13. Growth, Development and Sustainability

    Irina-Virginia Dragulanescu

    2013-11-01

    Full Text Available Describing the relationship of interdependence through the materials balance, will be argued how the economy is a subset of the environment and the environment the natural limit to any economic initiative, or the limits imposed by the laws of thermodynamics. The theoretical debate moves, then, from the concept of growth to that of development, understood this in its three dimensions: economic, social, environmental. Bring the different environmental positions in four versions of sustainability, with the gained awareness that it’s “a spectrum of overlapping sustainability positions from very weak to very strong”.

  14. Urban Growth and Transportation

    Gilles Duranton; Matthew A. Turner

    2012-01-01

    We estimate the effects of major roads and public transit on the growth of major cities in the US between 1980 and 2000. We find that a 10% increase in a city’s stock of roads causes about a 2% increase in its population and employment and a small decrease in its share of poor households over this 20 year period. We also find that a 10% increase in a city’s stock of large buses causes about a 0.8% population increase and a small increase in the share of poor households over this period. To es...

  15. Developing principles of growth

    Neergaard, Helle; Fleck, Emma

    of the principles of growth among women-owned firms. Using an in-depth case study methodology, data was collected from women-owned firms in Denmark and Ireland, as these countries are similar in contextual terms, e.g. population and business composition, dominated by micro, small and medium-sized enterprises....... Extending on principles put forward in effectuation theory, we propose that women grow their firms according to five principles which enable women’s enterprises to survive in the face of crises such as the current financial world crisis....

  16. Ion beam assisted film growth

    Itoh, T

    2012-01-01

    This volume provides up to date information on the experimental, theoretical and technological aspects of film growth assisted by ion beams.Ion beam assisted film growth is one of the most effective techniques in aiding the growth of high-quality thin solid films in a controlled way. Moreover, ion beams play a dominant role in the reduction of the growth temperature of thin films of high melting point materials. In this way, ion beams make a considerable and complex contribution to film growth. The volume will be essential reading for scientists, engineers and students working in thi

  17. Leverage, Investment, and Firm Growth

    Larry Lang; Eli Ofek; Rene M. Stulz

    1995-01-01

    We show that there is a negative relation between leverage and future growth at the firm level and, for diversified firms, at the segment level. Further, this negative relation between leverage and growth holds for firms with low Tobin's q, but not for high-q firms or firms in high-q industries. Therefore, leverage does not reduce growth for firms known to have good investment opportunities, but is negatively related to growth for firms whose growth opportunities are either not recognized by ...

  18. Probabilistic Mass Growth Uncertainties

    Plumer, Eric; Elliott, Darren

    2013-01-01

    Mass has been widely used as a variable input parameter for Cost Estimating Relationships (CER) for space systems. As these space systems progress from early concept studies and drawing boards to the launch pad, their masses tend to grow substantially, hence adversely affecting a primary input to most modeling CERs. Modeling and predicting mass uncertainty, based on historical and analogous data, is therefore critical and is an integral part of modeling cost risk. This paper presents the results of a NASA on-going effort to publish mass growth datasheet for adjusting single-point Technical Baseline Estimates (TBE) of masses of space instruments as well as spacecraft, for both earth orbiting and deep space missions at various stages of a project's lifecycle. This paper will also discusses the long term strategy of NASA Headquarters in publishing similar results, using a variety of cost driving metrics, on an annual basis. This paper provides quantitative results that show decreasing mass growth uncertainties as mass estimate maturity increases. This paper's analysis is based on historical data obtained from the NASA Cost Analysis Data Requirements (CADRe) database.

  19. FACET Emittance Growth

    Frederico, J; Hogan, M.J.; Nosochkov, Y.; Litos, M.D.; Raubenheimer, T.; /SLAC

    2011-04-05

    FACET, the Facility for Advanced Accelerator and Experimental Tests, is a new facility being constructed in sector 20 of the SLAC linac primarily to study beam driven plasma wakefield acceleration. The FACET beamline consists of a chicane and final focus system to compress the 23 GeV, 3.2 nC electron bunches to {approx}20 {micro}m long and {approx}10 {micro}m wide. Simulations of the FACET beamline indicate the short-duration and large, 1.5% rms energy spread beams may suffer a factor of four emittance growth from a combination of chromaticity, incoherent synchrotron radiation (ISR), and coherent synchrotron radiation (CSR). Emittance growth is directly correlated to head erosion in plasma wakefield acceleration and is a limiting factor in single stage performance. Studies of the geometric, CSR, and ISR components are presented. Numerical calculation of the rms emittance can be overwhelmed by long tails in the simulated phase space distributions; more useful definitions of emittance are given. A complete simulation of the beamline is presented as well, which agrees with design specifications.

  20. China urges rapid growth

    Hendry, S.

    1993-01-01

    This time last year China's paramount leader, Deng Xiaoping, launched the country on another bout of fast-paced economic growth and restructuring. After three years of riding out political and economic clampdown, foreign chemical companies were jerked awake by major changes in China's chemical industry. As the state becomes less involved with managing the economy, unleashing 12% gross national product growth, closer involvement with domestic factories has become attractive and essential. MCI officials say government funds will now be channeled toward clearing energy and transport bottlenecks, and chemical enterprises will be given more chance to turn a profit. They will be allowed to issue shares, seek foreign investment partners themselves, and bypass trading companies like China National Import-Export Corp. (Sinochem), the former state monopoly. Foreign analysts question whether China's finances and oil resources can support expansion. Even if they can, Cai estimates that ethylene imports will remain around the present level of 1 million tons. To further guarantee chemical supplies, China has invested in urea and polypropylene plants in the US and polystyrene plant in Hong Kong

  1. FACET Emittance Growth

    Frederico, Joel

    2011-01-01

    FACET, the Facility for Advanced Accelerator and Experimental Tests, is a new facility being constructed in sector 20 of the SLAC linac primarily to study beam driven plasma wakefield acceleration. The FACET beamline consists of a chicane and final focus system to compress the 23 GeV, 3.2 nC electron bunches to ∼20 (micro)m long and ∼10 (micro)m wide. Simulations of the FACET beamline indicate the short-duration and large, 1.5% rms energy spread beams may suffer a factor of four emittance growth from a combination of chromaticity, incoherent synchrotron radiation (ISR), and coherent synchrotron radiation (CSR). Emittance growth is directly correlated to head erosion in plasma wakefield acceleration and is a limiting factor in single stage performance. Studies of the geometric, CSR, and ISR components are presented. Numerical calculation of the rms emittance can be overwhelmed by long tails in the simulated phase space distributions; more useful definitions of emittance are given. A complete simulation of the beamline is presented as well, which agrees with design specifications.

  2. Molecular mechanisms of crystal growth

    Pina, C. M.

    2000-01-01

    In this paper I present an example of the research that the Mineral Surface Group of the Munster University is conducting in the field of Crystal Growth. Atomic Force Microscopy (Am) in situ observations of different barite (BaSO4) faces growing from aqueous solutions, in combination with computer simulations of the surface attachment of growth units allows us to test crystal growth models. Our results demonstrate the strong structural control that a crystal can exert on its own growth, revealing also the limitation of the classical crystal growth theories (two dimensional nucleation and spiral growth models) in providing a complete explanation for the growth behaviour at a molecular scale. (Author) 6 refs

  3. Springer Handbook of Crystal Growth

    Dhanaraj, Govindhan; Prasad, Vishwanath; Dudley, Michael

    2010-01-01

    Over the years, many successful attempts have been made to describe the art and science of crystal growth. Most modern advances in semiconductor and optical devices would not have been possible without the development of many elemental, binary, ternary, and other compound crystals of varying properties and large sizes. The objective of the Springer Handbook of Crystal Growth is to present state-of-the-art knowledge of both bulk and thin-film crystal growth. The goal is to make readers understand the basics of the commonly employed growth processes, materials produced, and defects generated. Almost 100 leading scientists, researchers, and engineers from 22 different countries from academia and industry have been selected to write chapters on the topics of their expertise. They have written 52 chapters on the fundamentals of bulk crystal growth from the melt, solution, and vapor, epitaxial growth, modeling of growth processes and defects, techniques of defect characterization as well as some contemporary specia...

  4. Geometrical approach to tumor growth.

    Escudero, Carlos

    2006-08-01

    Tumor growth has a number of features in common with a physical process known as molecular beam epitaxy. Both growth processes are characterized by the constraint of growth development to the body border, and surface diffusion of cells and particles at the growing edge. However, tumor growth implies an approximate spherical symmetry that makes necessary a geometrical treatment of the growth equations. The basic model was introduced in a former paper [C. Escudero, Phys. Rev. E 73, 020902(R) (2006)], and in the present work we extend our analysis and try to shed light on the possible geometrical principles that drive tumor growth. We present two-dimensional models that reproduce the experimental observations, and analyze the unexplored three-dimensional case, for which interesting conclusions on tumor growth are derived.

  5. Rapid growth within India

    Hayes, D.

    2000-01-01

    The Indian government has published (in Hydrocarbon Vision 2025) its ideas for a long term strategy for its oil industry which is currently growing at an unprecedented rate. Increasing domestic production and investment in oil exploration and production overseas figure strongly in the plan. At present, India has a refining surplus but with an annual growth of 8-10%, this will disappear in the next 2-3 years. The report recommends that India should maintain 90% self-sufficiency in refining. The report sees development of the domestic oil industry as globally competitive and helping safeguard India's assets. The capability of India's refineries, current upgrading, the newer refineries and plans for new projects are all mentioned

  6. 2010 responsible growth report

    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. Employment without Growth

    Nørgaard, Jørgen

    work over more income and consumption. Lower work input to production can take many differnet forms, such as job sharing, lowering production efficiency, reduction in labor force, etc. In this light it seems ridiculous to argue for certain economic development course on the ground that it will create...... more work. There are no indication that growth at Western economies increases satisfaction or happiness. A new look at the full economy divides it into professional economy and amateur economy, and it is suggested that a reversal of the trend hitherto to draw still more of the whole economy...... into the professional sphere, GDP, could contribute at the same time to a better satisfaction and a more sustainable development....

  8. Growth outside the core.

    Zook, Chris; Allen, James

    2003-12-01

    Growth in an adjacent market is tougher than it looks; three-quarters of the time, the effort fails. But companies can change those odds dramatically. Results from a five-year study of corporate growth conducted by Bain & Company reveal that adjacency expansion succeeds only when built around strong core businesses that have the potential to become market leaders. And the best place to look for adjacency opportunities is inside a company's strongest customers. The study also found that the most successful companies were able to consistently, profitably outgrow their rivals by developing a formula for pushing out the boundaries of their core businesses in predictable, repeatable ways. Companies use their repeatability formulas to expand into any number of adjacencies. Some companies make repeated geographic moves, as Vodafone has done in expanding from one geographic market to another over the past 13 years, building revenues from $1 billion in 1990 to $48 billion in 2003. Others apply a superior business model to new segments. Dell, for example, has repeatedly adapted its direct-to-customer model to new customer segments and new product categories. In other cases, companies develop hybrid approaches. Nike executed a series of different types of adjacency moves: it expanded into adjacent customer segments, introduced new products, developed new distribution channels, and then moved into adjacent geographic markets. The successful repeaters in the study had two common characteristics. First, they were extraordinarily disciplined, applying rigorous screens before they made an adjacency move. This discipline paid off in the form of learning curve benefits, increased speed, and lower complexity. And second, in almost all cases, they developed their repeatable formulas by studying their customers and their customers' economics very, very carefully.

  9. International growth of neuropsychology.

    Ponsford, Jennie

    2017-11-01

    Twenty-five years ago, the field of neuropsychology was well established in North America, Europe, and Australia, with less presence elsewhere. This article discusses the development of neuropsychology over the last 25 years in other regions. The growth of neuropsychology in Asia, Africa, the Middle East, Central and South America, and New Zealand is reviewed. Sources drawn on include a 2016 edition of The Clinical Neuropsychologist describing the practice of neuropsychology in 18 countries; papers on the profession of neuropsychology in Latin America (Arango-Lasprilla, Stevens, Paredes, Ardila, & Rivera, 2016), the history of neuropsychology in Asia (Lee, Wang, & Collinson, 2016), and neuropsychology in Central America (Judd, 2017); INSNET; and personal communications. There has been tremendous variability in the development of neuropsychology across these regions over the last 25 years. Obstacles to the growth of neuropsychology have included economic constraints on health care provision, limited availability of appropriate assessment and treatment methods, linguistic diversity and illiteracy, stigma toward and/or lack of awareness of neuropsychological disorders, lack of graduate training and clinical supervision, absence of accreditation of neuropsychologists as a clinical profession, poor pay, and diminished visibility of the field within the regional culture. Despite these obstacles, neuropsychological research and practice is establishing itself in these regions and has grown significantly over the last quarter century. Major challenges remain in establishing awareness of the significance of and developing culturally appropriate methods of assessing and rehabilitating cognitive aspects of brain disorders, training programs, recognition as a profession, and dedicated funding for neuropsychology positions. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

  10. Thermodynamics of firms' growth

    Zambrano, Eduardo; Hernando, Alberto; Hernando, Ricardo; Plastino, Angelo

    2015-01-01

    The distribution of firms' growth and firms' sizes is a topic under intense scrutiny. In this paper, we show that a thermodynamic model based on the maximum entropy principle, with dynamical prior information, can be constructed that adequately describes the dynamics and distribution of firms' growth. Our theoretical framework is tested against a comprehensive database of Spanish firms, which covers, to a very large extent, Spain's economic activity, with a total of 1 155 142 firms evolving along a full decade. We show that the empirical exponent of Pareto's law, a rule often observed in the rank distribution of large-size firms, is explained by the capacity of economic system for creating/destroying firms, and that can be used to measure the health of a capitalist-based economy. Indeed, our model predicts that when the exponent is larger than 1, creation of firms is favoured; when it is smaller than 1, destruction of firms is favoured instead; and when it equals 1 (matching Zipf's law), the system is in a full macroeconomic equilibrium, entailing ‘free’ creation and/or destruction of firms. For medium and smaller firm sizes, the dynamical regime changes, the whole distribution can no longer be fitted to a single simple analytical form and numerical prediction is required. Our model constitutes the basis for a full predictive framework regarding the economic evolution of an ensemble of firms. Such a structure can be potentially used to develop simulations and test hypothetical scenarios, such as economic crisis or the response to specific policy measures. PMID:26510828

  11. [Economic growth with zero population growth and with declining population].

    Kurz, R

    1982-05-01

    The effects of both zero population growth and a declining population on economic growth are considered. Although the neoclassical theory of economic growth leads to optimistic results in such cases, the author suggests that this theory cannot be used as a basis for political action. The need for further research into the economic effects of a stationary or declining population is stressed. (summary in ENG)

  12. Growth assessment in diagnosis of Fetal Growth Restriction. Review

    Albu, AR; Horhoianu, IA; Dumitrascu, MC; Horhoianu, V

    2014-01-01

    Abstract The assessment of fetal growth represents a fundamental step towards the identification of the true growth restricted fetus that is associated to important perinatal morbidity and mortality. The possible ways of detecting abnormal fetal growth are taken into consideration in this review and their strong and weak points are discussed. An important debate still remains about how to discriminate between the physiologically small fetus that does not require special surveillance and the t...

  13. Growth Mechanism of Microbial Colonies

    Zhu, Minhui; Martini, K. Michael; Kim, Neil H.; Sherer, Nicholas; Lee, Jia Gloria; Kuhlman, Thomas; Goldenfeld, Nigel

    Experiments on nutrient-limited E. coli colonies, growing on agar gel from single cells reveal a power-law distribution of sizes, both during the growth process and in the final stage when growth has ceased. We developed a Python simulation to study the growth mechanism of the bacterial population and thus understand the broad details of the experimental findings. The simulation takes into account nutrient uptake, metabolic function, growth and cell division. Bacteria are modeled in two dimensions as hard circle-capped cylinders with steric interactions and elastic stress dependent growth characteristics. Nutrient is able to diffuse within and between the colonies. The mechanism of microbial colony growth involves reproduction of cells within the colonies and the merging of different colonies. We report results on the dynamic scaling laws and final state size distribution, that capture in semi-quantitative detail the trends observed in experiment. Supported by NSF Grant 0822613.

  14. SECTORAL SHARES AND ECONOMIC GROWTH

    Ahmad, Nisar; Naveed, Amjad; Naz, Amber

    2013-01-01

    believe that structural change is an unimportant side effect of the economic development. On the contrary, economists associated with the World Bank and some others posit that growth is brought about by the changes in sectoral composition. The objective of this study is to empirically test...... the relationship between sectoral shares and economic growth by using the panel data for 20 developed countries. The results of the granger causality suggest that both services and agriculture sectors do granger cause economic growth, whereas industrial sector does not granger cause growth. Reverse causality does...... not hold for any of the three sectors. The results of Barro and Non-Barro regressions along with the set of control variables have suggested that services sector is negatively affecting growth, whereas both industrial and agriculture shares are positively affect economic growth....

  15. Hopper Growth of Salt Crystals.

    Desarnaud, Julie; Derluyn, Hannelore; Carmeliet, Jan; Bonn, Daniel; Shahidzadeh, Noushine

    2018-06-07

    The growth of hopper crystals is observed for many substances, but the mechanism of their formation remains ill understood. Here we investigate their growth by performing evaporation experiments on small volumes of salt solutions. We show that sodium chloride crystals that grow very fast from a highly supersaturated solution form a peculiar form of hopper crystal consisting of a series of connected miniature versions of the original cubic crystal. The transition between cubic and such hopper growth happens at a well-defined supersaturation where the growth rate of the cubic crystal reaches a maximum (∼6.5 ± 1.8 μm/s). Above this threshold, the growth rate varies as the third power of supersaturation, showing that a new mechanism, controlled by the maximum speed of surface integration of new molecules, induces the hopper growth of cubic crystals in cascade.

  16. Growth patterns and annual growth cycle of Acacia karroo Hayne in ...

    ... karroo; alice; botany; compensatory growth; condition; development; eastern cape; emergence; environmental conditions; field study; growth cycle; growth initiation; growth patterns; growth strategy; leaf growth; plant growth; savanna; shoot growth; soil depth; soil moisture; south africa; university of fort hare; water stress ...

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

    Vandenburgh, Herman H.

    1993-01-01

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

  18. Population growth and infant mortality

    Fabella, Christina

    2008-01-01

    The relationship between population growth and economic outcomes is an issue of great policy significance. In the era of the Millennium Development Goals, poverty and its correlates have become the compelling issues. Economic growth may not automatically translate into reductions in poverty and its correlates (may not trickle down) if income distribution is at the same time worsening. We therefore investigate the direct effect of population growth on infant mortality for various income catego...

  19. Financing Asia’s Growth

    Estrada, Gemma; Noland, Marcus; Park, Donghyun; Ramayandi, Arief

    2015-01-01

    Recent key challenges highlight the need to revisit Asia's financial development. These include the region's growth slowdown since the global crisis, compounded by a less benign external environment; internal structural challenges, such as population aging; and the maturing of much of the region into middle-income status. The evolving shift in the region's growth paradigm from one based primarily on investment to one based on both investment and productivity growth also underscores the urgenc...

  20. Linking Ethics and Economic Growth

    Foss, Nicolai Juul

    2012-01-01

    Hunt (2012) builds on his work concerning ethics and resource-advantage theory to link personal ethical standards, societal norms, and economic growth but offers few details concerning the precise mechanisms that link ethics and growth. This comment suggests a number of such mechanisms – for exam...... – for example, the influence of prevailing ethical norms on the aggregate elasticity of substitution and, therefore, total factor productivity and growth....

  1. Stochastic models for tumoral growth

    Escudero, Carlos

    2006-01-01

    Strong experimental evidence has indicated that tumor growth belongs to the molecular beam epitaxy universality class. This type of growth is characterized by the constraint of cell proliferation to the tumor border, and surface diffusion of cells at the growing edge. Tumor growth is thus conceived as a competition for space between the tumor and the host, and cell diffusion at the tumor border is an optimal strategy adopted for minimizing the pressure and helping tumor development. Two stoch...

  2. Growth curves for Laron syndrome.

    Laron, Z; Lilos, P; Klinger, B

    1993-01-01

    Growth curves for children with Laron syndrome were constructed on the basis of repeated measurements made throughout infancy, childhood, and puberty in 24 (10 boys, 14 girls) of the 41 patients with this syndrome investigated in our clinic. Growth retardation was already noted at birth, the birth length ranging from 42 to 46 cm in the 12/20 available measurements. The postnatal growth curves deviated sharply from the normal from infancy on. Both sexes showed no clear pubertal spurt. Girls co...

  3. Electricity regulation and economic growth

    Costa, M. Teresa (Maria Teresa), 1951-; Garcia-Quevedo, Jose; Trujillo-Baute, Elisa

    2018-01-01

    The main objective of this paper is to analyse the effect of electricity regulation on economic growth. Although the relationship between electricity consumption and economic growth has been extensively analysed in the empirical literature, this framework has not been used to estimate the effect of electricity regulation on economic growth. Understanding this effect is essential for the assessment of regulatory policy. Specifically, we assess the effects of two major areas of regulation, rene...

  4. Political Instability and Economic Growth

    Alberto Alesina; Sule Ozler; Nouriel Roubini; Phillip Swagel

    1992-01-01

    This paper investigates the relationship between political instability and per capita GDP growth in a sample of 113 countries for the period 1950-1982. We define ?political instability? as the propensity of a government collapse, and we estimate a model in which political instability and economic growth are jointly determined. The main result of this paper is that in countries and time periods with a high propensity of government collapse, growth is significantly lower than otherwise. This ef...

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

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

    2015-07-01

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

  6. Gene regulation by growth factors

    Metz, R.; Gorham, J.; Siegfried, Z.; Leonard, D.; Gizang-Ginsberg, E.; Thompson, M.A.; Lawe, D.; Kouzarides, T.; Vosatka, R.; MacGregor, D.; Jamal, S.; Greenberg, M.E.; Ziff, E.B.

    1988-01-01

    To coordinate the proliferation and differentiation of diverse cell types, cells of higher eukaryotes communicate through the release of growth factors. These peptides interact with specific transmembrane receptors of other cells and thereby generate intracellular messengers. The many changes in cellular physiology and activity that can be induced by growth factors imply that growth factor-induced signals can reach the nucleus and control gene activity. Moreover, current evidence also suggests that unregulated signaling along such pathways can induce aberrant proliferation and the formation of tumors. This paper reviews investigations of growth factor regulation of gene expression conducted by the authors' laboratory

  7. Growth, Employment and Structural Change

    Aggarwal, Aradhna

    2016-01-01

    This paper studies the decomposition of GSDP growth per capita in Punjab via-a-vis 15 other states in India during 1993–94 and 2011–12 in terms of employment and productivity growth. Specifically, it focuses on the role of employment growth and structural change in employment on economic growth...... but structural shifts have paid off well in terms of diversification of the economy and their contribution to labour productivity especially for manufacturing. Overall employment effect had been negative but this was essentially due to contraction in the labour force; the employment rate effect turned out...

  8. Quality, Export and Economic Growth

    Madsen, Erik Strøjer; Pedersen, Kurt

    1998-01-01

    in an international context. The paper, therefore, addresses the complicated interactions between economic growth, export performance and quality. The contribution of the paper, compared to other growth accounting research, is the inclusion of quality data, quality being a significant mirror of technological...... development. The countries covered by the research represent a wide variation in terms of economic development, from poor LDC's to the most developed industrial nations. The empirical results reveal a probable strong relationship between quality/price and export growth as well as economic growth. This new...

  9. Variations in growth pattern and predictablity of liveweight growth of ...

    The prediction equations results for rate of liveweight growth showed that of the four models used, the quadratic function was the best predictor of liveweight growth, as indicated by the highest and significant R2 value of 90.7 %. This was closely followed by the linear function which had a significant R2 value of 88.1 %.

  10. Can extrauterine growth approximate intrauterine growth? Should it?

    Sauer, Pieter J. J.

    Most studies evaluating the growth of preterm infants use the so-called intrauterine growth curve and reference fetus as standards. These curves might not be the optimal standards, however, for several reasons. The curves were constructed from small numbers of infants with uncertainty about

  11. Growth of the Pamir

    Gloaguen, R.; Ratschbacher, L.

    2009-04-01

    We aim to establish the Late Cenozoic deformation field of the Pamir by localizing and characterizing active and neotectonic deformation structures, and setting up the drainage-basin, river-capture, river- reversal, and regional erosion history. The project thus aims to record the short-term, upper crustal response to active intra-continental subduction, orocline formation, and erosion. Our hypothesis is that the neotectonics is governed by subduction beneath the frontal part of the orocline, E-W extension in the intra-plateau Karakul-lake rift, and transtension (east) and transpression (west) along the lateral margins of the orocline, a result of oroclinal formation, rotation of the Indian indenter, and focused precipitation caused by the Westerlies. The model for the evolution of the drainage system involves: growth of the Pamir by N-ward propagating deformation, establishing E-trending belts of shortening and rivers/drainages; diversion and blocking of these rivers by the development of the lateral boundaries of the orocline that resulted in river capture and reversal. Even the present-day Panj (Amu Darya) is affected by ongoing uplift: tilted river terraces, wind gaps, and abnormal intersection of streams of different order indicate that large parts of the river have changed flow direction. The determination of a number of geomorphic indices with remote sensing techniques help us to identify areas experiencing tectonic deformation.

  12. Posttraumatic growth in psychosis

    Yael Mazor

    2016-12-01

    Full Text Available Objective: Recent research has shown high rates of exposure to trauma among people with serious mental illness (SMI. In addition studies suggest that psychosis and mental illness-related experiences can be extremely traumatic. While some individuals develop full blown PTSD related to these experiences, it has been noted that some may also experience posttraumatic growth (PTG. However, few studies have examined PTG as a possible outcome in people who have experienced psychosis. Method: To further understand the relationships between psychosis and PTG, 121 participants were recruited from community mental health rehabilitation centers and administered trauma and psychiatric questionnaires. Results: High levels of traumatic exposure were found in the sample. Regarding our main focus of study we observed that people who endured psychosis can experience PTG, and that PTG is mediated by meaning making and coping self-efficacy appraisal. Psychotic symptoms were found to be a major obstacle to meaning making, coping self-efficacy, and PTG, whereas negative symptoms were found to be significantly related to PTG when mediated by meaning making and coping self-efficacy. Conclusion: The current research provides preliminary evidence for potential role of meaning making and coping self-efficacy as mediators of PTG in the clinical, highly traumatized population of people with SMI who have experienced psychosis. This may have both research as well as clinical practice relevance for the field of psychiatric rehabilitation.

  13. ECOLOGICAL GROWTH BOUNDARIES

    Anna BLUSZCZ

    2017-01-01

    Full Text Available The trends of the society for the continuous growth, combined with the demographic changes, today have led to the important ecological problems on a global scale, which include, among others: the increased use of non-renewable natu-ral resources, an increase of the greenhouse gas emissions, contamination of soil, water, air and the progressive degra-dation of ecosystems. In the face of such serious threats the global initiatives of all countries are important to limit the results of the excessive consumption. The aim of the article is to present the methods of measurement of the consump-tion level of natural resources by the societies and the examination of relationships between the level of development of the societies and the use of resources. The popular measure – the ecological footprint – was used as a measurement method for the consumption of the today’s generations in relation to the regenerative possibilities of the natural envi-ronment. On the other hand, as the assessment method for the level of development of societies – the Human Develop-ment Index (HDI, including three basic areas: the life expectancy, GDP level per capita and education was used. The results of the research indicate that the current trend of the unlimited consumption of the highly developed countries takes place at the expense of the future generations.

  14. The initial growth stage in PVT growth of aluminum nitride

    Heimann, P.; Epelbaum, B.M.; Bickermann, M.; Winnacker, A. [Department of Materials Science 6, University of Erlangen-Nuernberg, Martensstr. 7, 91058 Erlangen (Germany); Nagata, S. [Functional Materials Development Center, Research Laboratories, JFE Mineral Company, Ltd., 1, Niihama-cho, Chuou-ku, Chiba-shi, Chiba 260-0826 (Japan)

    2006-06-15

    The main issue in homoepitaxial growth of aluminum nitride (AlN) on native seed substrates is the formation of an aluminum oxynitride (AlON) layer at temperatures between 1850-1950 C leading to polycrystalline growth. On the contrary, heteroepitaxial growth of AlN on silicon carbide (SiC) is relatively easy to achieve due to natural formation of a thin molten layer of (Al{sub 2}OC{sub x}) on the seed surface and consequent growth of AlN via the molten buffer layer. Optimization of the seeding process can be achieved by use of ultra-pure starting material. Another critical issue of AlN growth on SiC is cracking of the grown layer upon cooling as a result of different thermal expansion coefficients. (copyright 2006 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  15. Corruption and economic growth with non constant labor force growth

    Brianzoni, Serena; Campisi, Giovanni; Russo, Alberto

    2018-05-01

    Based on Brianzoni et al. [1] in the present work we propose an economic model regarding the relationship between corruption in public procurement and economic growth. We extend the benchmark model by introducing endogenous labor force growth, described by the logistic equation. The results of previous studies, as Del Monte and Papagni [2] and Mauro [3], show that countries are stuck in one of the two equilibria (high corruption and low economic growth or low corruption and high economic growth). Brianzoni et al. [1] prove the existence of a further steady state characterized by intermediate levels of capital per capita and corruption. Our aim is to investigate the effects of the endogenous growth around such equilibrium. Moreover, due to the high number of parameters of the model, specific attention is given to the numerical simulations which highlight new policy measures that can be adopted by the government to fight corruption.

  16. Extracellular matrix organization modulates fibroblast growth and growth factor responsiveness.

    Nakagawa, S; Pawelek, P; Grinnell, F

    1989-06-01

    To learn more about the relationship between extracellular matrix organization, cell shape, and cell growth control, we studied DNA synthesis by fibroblasts in collagen gels that were either attached to culture dishes or floating in culture medium during gel contraction. After 4 days of contraction, the collagen density (initially 1.5 mg/ml) reached 22 mg/ml in attached gels and 55 mg/ml in floating gels. After contraction, attached collagen gels were well organized; collagen fibrils were aligned in the plane of cell spreading; and fibroblasts had an elongated, bipolar morphology. Floating collagen gels, however, were unorganized; collagen fibrils were arranged randomly; and fibroblasts had a stellate morphology. DNA synthesis by fibroblasts in contracted collagen gels was suppressed if the gels were floating in medium but not if the gels were attached, and inhibition was independent of the extent of gel contraction. Therefore, growth of fibroblasts in contracted collagen gels could be regulated by differences in extracellular matrix organization and cell shape independently of extracellular matrix density. We also compared the responses of fibroblasts in contracted collagen gels and monolayer culture to peptide growth factors including fibroblast growth factor, platelet-derived growth factor, transforming growth factor-beta, and interleukin 1. Cells in floating collagen gels were generally unresponsive to any of the growth factors. Cells in attached collagen gels and monolayer culture were affected similarly by fibroblast growth factor but not by the others. Our results indicate that extracellular matrix organization influenced not only cell growth, but also fibroblast responsiveness to peptide growth factors.

  17. Growth at adolescence. Clinical correlates.

    Daniel, W A

    1985-03-01

    Several highly significant changes occur within a relatively short period of time during adolescence. Great alteration in physique, developmental progress in thinking, and psychologic gains toward attaining ego identity take place but not always synchronously. Attention is paid to physical changes because they are visible and are of intense concern to adolescents, but physicians and other professionals should remember cognitive and psychosocial growth are affected by physical growth, and vice versa. Often there is a temporary disequilibrium in the relationship of these three areas of growth, and this can affect one or another part of the developmental pattern. It is therefore necessary to remind ourselves of the diversity of adolescent growth, and of adolescents, when caring for a young patient and be cognizant of growth in areas other than physical. More and more children with congenital or acquired handicaps are living to become adolescents and perhaps adults. Handicaps can be limited to one of the three major areas of growth or involve them all in varying degrees. For example, sickle cell disease, Crohn's disease, or ulcerative colitis may postpone physical growth for a significant period; this lack of pubertal change can affect psychosocial development but usually does not impair cognitive growth. Mental retardation may have no apparent effect on physical growth but can handicap the adolescent's psychosocial development. Growth still occurs in a sequential pattern but often it seems that handicapped youngsters reach a developmental milestone by a series of "detours." Physicians must recognize these lags or differences and try to facilitate progress, promote self-esteem, and provide understanding. Much can be done with anticipatory guidance. Adolescence often provides the opportunity to overcome past damage or, in some instances, to start anew on a more optimal program for physical and psychosocial growth. Young adolescent boys and girls usually look to the

  18. Nutritional catch-up growth.

    Gat-Yablonski, Galia; Pando, Rakefet; Phillip, Moshe

    2013-01-01

    Malnutrition, marked by variant nutrient deficiencies, is considered a leading cause of stunted growth worldwide. In developing countries, malnutrition is caused mainly by food shortage and infectious diseases. Malnutrition may also be found in the developed world, where it is due mostly to prematurity, chronic diseases, and anorexia nervosa. In most cases, when food consumption is corrected, spontaneous catch-up (CU) growth occurs. However, CU growth is not always complete, leading to growth deficits. Therefore, it is important to understand the mechanisms that govern this process. Using a rat model of food restriction followed by refeeding, we established a nutrition-induced CU growth model. Levels of leptin and insulin-like growth factor-1 were found to significantly decrease when food was restricted and to increase already 1 day after refeeding. Gene expression analysis of the growth plate revealed that food restriction specifically affects transcription factors such as the hypoxia inducible factor-1 and its downstream targets on the one hand, and global gene expression, indicating epigenetic regulation, on the other. Food restriction also reduced the level of several microRNAs, including the chondrocyte-specific miR-140, which led to an increase in its target, SIRT1, a class III histone deacetylase. These findings may explain the global changes in gene expression observed under nutritional manipulation. We suggest that multiple levels of regulation, including transcription factors, epigenetic mechanisms, and microRNAs respond to nutritional cues and offer a possible explanation for some of the effects of food restriction on epiphyseal growth plate growth. The means whereby these components sense changes in nutritional status are still unknown. Deciphering the role of epigenetic regulation in growth may pave the way for the development of new treatments for children with growth disorders. Copyright © 2013 S. Karger AG, Basel.

  19. Entrepreneurship Education and Economic Growth

    Pedersen, Jonna; Lindquist, Carl Rickard

    . This paper addresses the presumptions behind the project. The presumptions in relation to entrepreneurship demonstrate that the effort should target both growth entrepreneurs and SMEs in a wide sense; there is a need for growth entrepreneurs with ambitions to generate breakthrough innovation as well...

  20. Ecological economics and economic growth.

    Victor, Peter A

    2010-01-01

    Boulding's 1966 paper on the economics of spaceship Earth established the framework for ecological economics and an understanding of economic growth. In ecological economics, economies are conceptualized as open subsystems of the closed biosphere and are subject to biophysical laws and constraints. Economic growth measured as an increase in real gross domestic product (GDP) has generally been associated with increases in the use of energy and materials and the generation of wastes. Scale, composition, and technology are the proximate determinants of environmental impacts. They are often reduced to two: scale (GDP) and intensity (impact per unit GDP). New work described in this paper defines "green" growth as intensity that declines faster than scale increases. Similarly, "brown" growth occurs when intensity declines more slowly than increases in scale, and "black" growth happens when both scale and intensity increase. These concepts are then related to the environmental Kuznets curve, which can be understood as a transition from brown to green growth. Ecological economics provides a macroperspective on economic growth. It offers broad policy principles, and it challenges the primacy of economic growth as a policy objective, but many important questions remain.

  1. Technical Education and Economic Growth

    First page Back Continue Last page Graphics. Technical Education and Economic Growth. Technical Education and Economic Growth. Review of the Present Status. Expanding no.s and impairment of quality; Faculty shortage; Grim situation at Masters and PhD levels; Regional imbalance; Absence of International flavour ...

  2. Chemical Control of Plant Growth.

    Agricultural Research Center (USDA), Beltsville, MD.

    Seven experiments are presented in this Science Study Aid to help students investigate the control of plant growth with chemicals. Plant growth regulators, weed control, and chemical pruning are the topics studied in the experiments which are based on investigations that have been and are being conducted at the U. S. Agricultural Research Center,…

  3. Growth curves for Laron syndrome.

    Laron, Z; Lilos, P; Klinger, B

    1993-01-01

    Growth curves for children with Laron syndrome were constructed on the basis of repeated measurements made throughout infancy, childhood, and puberty in 24 (10 boys, 14 girls) of the 41 patients with this syndrome investigated in our clinic. Growth retardation was already noted at birth, the birth length ranging from 42 to 46 cm in the 12/20 available measurements. The postnatal growth curves deviated sharply from the normal from infancy on. Both sexes showed no clear pubertal spurt. Girls completed their growth between the age of 16-19 years to a final mean (SD) height of 119 (8.5) cm whereas the boys continued growing beyond the age of 20 years, achieving a final height of 124 (8.5) cm. At all ages the upper to lower body segment ratio was more than 2 SD above the normal mean. These growth curves constitute a model not only for primary, hereditary insulin-like growth factor-I (IGF-I) deficiency (Laron syndrome) but also for untreated secondary IGF-I deficiencies such as growth hormone gene deletion and idiopathic congenital isolated growth hormone deficiency. They should also be useful in the follow up of children with Laron syndrome treated with biosynthetic recombinant IGF-I. PMID:8333769

  4. ICT, Innovation and Productivity Growth

    Fosse, Henrik; Jacobsen, Joannes; Sørensen, Anders

    This CEBR report presents new evidence which suggests that investments in Information and Communication Technology (ICT) further productivity growth in Danish firms by stimulating innovation activities.......This CEBR report presents new evidence which suggests that investments in Information and Communication Technology (ICT) further productivity growth in Danish firms by stimulating innovation activities....

  5. The Growth-Inequality Association:

    Bjørnskov, Christian

    2008-01-01

    This note suggests that the association between income inequality and economic growth rates might arguably depend on the political ideology of incumbent governments. Estimates indicate that under leftwing governments, inequality is negatively associated with growth while the association is positive...... under rightwing governments. This may provide a qualification to recent studies of inequality....

  6. Forces Influencing Rural Community Growth.

    Rainey, Kenneth D.

    The paper briefly focuses on two questions: Can the recent growth trend be expected to continue into the future? and What does this imply as far as public policy and programs are concerned? Statistics on growth in the seventies suggest three possibilities: a change in the functions of metropolitan and nonmetropolitan areas; the decline of the city…

  7. Mould growth on building materials

    Fog Nielsen, K.

    Mould growth in buildings is associated with adverse health effects among the occupants of the building. However actual growth only occurs in damp and water-damaged materials, and is an increasing problem in Denmark, due to less robust constructions, inadequate maintenance, and too little...

  8. Growth Hormone and Endocrinopathies

    Kim, K W; Choe, K O; Park, C Y; Lee, H; Son, H Y; Huh, K B; Ryu, K J [Yonsei University College of Medicine, Seoul (Korea, Republic of)

    1979-03-15

    This is an analysis of 39 patients studied at the Yonsei Medical Center from January, 1976 to March 1979. Of these 35 patient were suspected of having hypothalamic insufficiency and subjected to the L-Dopa stimulation test to observe growth hormone secretary function while four acromegaly patient received the glucose loading test and L-Dopa stimulation test. The results are as follows: 1) The basal level of GH in the various disease was as follows: a) The basal level was lower than the control level but was not statistically significant b) In diabetes the mean value tended to higher than the control level but was not significant statistically c) In all four acromegaly patients the GH level was significantly higher than the control level 2) Of 13 patients with diabetes, nine had diabetic retinopathy, and of those nine, six showed increased L-Dopa response. However, of the four non retinopathic DM patients, only one showed increased response to L-Dopa. 3) Two patients out of ten with Sheehan's syndrome responded to L-Dopa stimulation. 4) One Patient of eight with pituitary chromophobe adenoma responded to L-Dopa stimulation. 5) Four acromegaly patients revealed 3 acidophilic adenoma and one chromophobe adenoma histologically. Of patients receiving the L-Dopa stimulation test. Two showed a paradoxical response. Two patients who received the glucose loading test showed suppressed response. 6) Of two craniopharyngioma patients, one showed increased GH response after L-Dopa stimulation. Increased response of GH after L-Dopa stimulation was seen in one two craniopharyngioma patients and also in one of two patients with short structure.

  9. Growth Hormone and Endocrinopathies

    Kim, K. W.; Choe, K. O.; Park, C. Y.; Lee, H.; Son, H. Y.; Huh, K. B.; Ryu, K. J. [Yonsei University College of Medicine, Seoul (Korea, Republic of)

    1979-03-15

    This is an analysis of 39 patients studied at the Yonsei Medical Center from January, 1976 to March 1979. Of these 35 patient were suspected of having hypothalamic insufficiency and subjected to the L-Dopa stimulation test to observe growth hormone secretary function while four acromegaly patient received the glucose loading test and L-Dopa stimulation test. The results are as follows: 1) The basal level of GH in the various disease was as follows: a) The basal level was lower than the control level but was not statistically significant b) In diabetes the mean value tended to higher than the control level but was not significant statistically c) In all four acromegaly patients the GH level was significantly higher than the control level 2) Of 13 patients with diabetes, nine had diabetic retinopathy, and of those nine, six showed increased L-Dopa response. However, of the four non retinopathic DM patients, only one showed increased response to L-Dopa. 3) Two patients out of ten with Sheehan's syndrome responded to L-Dopa stimulation. 4) One Patient of eight with pituitary chromophobe adenoma responded to L-Dopa stimulation. 5) Four acromegaly patients revealed 3 acidophilic adenoma and one chromophobe adenoma histologically. Of patients receiving the L-Dopa stimulation test. Two showed a paradoxical response. Two patients who received the glucose loading test showed suppressed response. 6) Of two craniopharyngioma patients, one showed increased GH response after L-Dopa stimulation. Increased response of GH after L-Dopa stimulation was seen in one two craniopharyngioma patients and also in one of two patients with short structure.

  10. Growth Hormone and Endocrinopathies

    Kim, K. W.; Choe, K. O.; Park, C. Y.; Lee, H.; Son, H. Y.; Huh, K. B.; Ryu, K. J.

    1979-01-01

    This is an analysis of 39 patients studied at the Yonsei Medical Center from January, 1976 to March 1979. Of these 35 patient were suspected of having hypothalamic insufficiency and subjected to the L-Dopa stimulation test to observe growth hormone secretary function while four acromegaly patient received the glucose loading test and L-Dopa stimulation test. The results are as follows: 1) The basal level of GH in the various disease was as follows: a) The basal level was lower than the control level but was not statistically significant b) In diabetes the mean value tended to higher than the control level but was not significant statistically c) In all four acromegaly patients the GH level was significantly higher than the control level 2) Of 13 patients with diabetes, nine had diabetic retinopathy, and of those nine, six showed increased L-Dopa response. However, of the four non retinopathic DM patients, only one showed increased response to L-Dopa. 3) Two patients out of ten with Sheehan's syndrome responded to L-Dopa stimulation. 4) One Patient of eight with pituitary chromophobe adenoma responded to L-Dopa stimulation. 5) Four acromegaly patients revealed 3 acidophilic adenoma and one chromophobe adenoma histologically. Of patients receiving the L-Dopa stimulation test. Two showed a paradoxical response. Two patients who received the glucose loading test showed suppressed response. 6) Of two craniopharyngioma patients, one showed increased GH response after L-Dopa stimulation. Increased response of GH after L-Dopa stimulation was seen in one two craniopharyngioma patients and also in one of two patients with short structure.

  11. Stochastic models for tumoral growth

    Escudero, Carlos

    2006-02-01

    Strong experimental evidence has indicated that tumor growth belongs to the molecular beam epitaxy universality class. This type of growth is characterized by the constraint of cell proliferation to the tumor border and the surface diffusion of cells at the growing edge. Tumor growth is thus conceived as a competition for space between the tumor and the host, and cell diffusion at the tumor border is an optimal strategy adopted for minimizing the pressure and helping tumor development. Two stochastic partial differential equations are reported in this paper in order to correctly model the physical properties of tumoral growth in (1+1) and (2+1) dimensions. The advantage of these models is that they reproduce the correct geometry of the tumor and are defined in terms of polar variables. An analysis of these models allows us to quantitatively estimate the response of the tumor to an unfavorable perturbation during growth.

  12. Dietary arginine and linear growth

    van Vught, Anneke J A H; Dagnelie, Pieter C; Arts, Ilja C W

    2013-01-01

    Child Intervention Study during 2001-2 (baseline), and at 3-year and 7-year follow-up, were used. Arginine intake was estimated via a 7 d precoded food diary at baseline and 3-year follow-up. Data were analysed in a multilevel structure in which children were embedded within schools. Random intercept......The amino acid arginine is a well-known growth hormone (GH) stimulator and GH is an important modulator of linear growth. The aim of the present study was to investigate the effect of dietary arginine on growth velocity in children between 7 and 13 years of age. Data from the Copenhagen School...... and slopes were defined to estimate the association between arginine intake and growth velocity, including the following covariates: sex; age; baseline height; energy intake; puberty stage at 7-year follow-up and intervention/control group. The association between arginine intake and growth velocity...

  13. Population growth, poverty and health.

    Kibirige, J S

    1997-07-01

    One of the most popular explanations for the many problems that face Africa is population growth. Africa's population has doubled since 1960. Africa has the highest fertility rate in the world and the rate of population growth is higher than in any other region. At the same time, Africa faces a social and economic situation that is viewed by many as alarming. Among the problems that devastate Africa is that of persistent poor health. Africa has lower life expectancy, higher mortality rates and is affected by more disease and illness conditions than any other region. Focusing on sub-Saharan Africa, this paper examines the relationship between population growth, poverty and poor health. While most analyses have focused on population growth as an original cause of poverty and underdevelopment, this paper argues that while both population growth and poor health play a significant role in exacerbating the problem of poverty, they are themselves primary consequences of poverty rather than its cause.

  14. Growth morphologies of crystal surfaces

    Xiao, Rong-Fu; Alexander, J. Iwan D.; Rosenberger, Franz

    1991-03-01

    We have expanded our earlier Monte Carlo model [Phys. Rev. A 38, 2447 (1988); J. Crystal Growth 100, 313 (1990)] to three dimensions and included reevaporation after accommodation and growth on dislocation-induced steps. We found again that, for a given set of growth parameters, the critical size, beyond which a crystal cannot retain its macroscopically faceted shape, scales linearly with the mean free path in the vapor. However, the three-dimensional (3D) the systems show increased shape stability compared to corresponding 2D cases. Extrapolation of the model results to mean-free-path conditions used in morphological stability experiments leads to order-of-magnitude agreement of the predicted critical size with experimental findings. The stability region for macroscopically smooth (faceted) surfaces in the parameter space of temperature and supersaturation depends on both the surface and bulk diffusion. While surface diffusion is seen to smooth the growth morphology on the scale of the surface diffusion length, bulk diffusion is always destabilizing. The atomic surface roughness increases with increase in growth temperature and supersaturation. That is, the tendency of surface kinetics anisotropies to stabilize the growth shape is reduced through thermal and kinetic roughening. It is also found that the solid-on-solid assumption, which can be advantageously used at low temperatures and supersaturations, is insufficient to describe the growth dynamics of atomically rough interfaces where bulk diffusion governs the process. For surfaces with an emerging screw dislocation, we find that the spiral growth mechanism dominates at low temperatures and supersaturations. The polygonization of a growth spiral decreases with increasing temperature or supersaturation. When the mean free path in the nutrient is comparable to the lattice constant, the combined effect of bulk and surface diffusion reduces the terrace width of a growth spiral in its center region. At elevated

  15. Growth of maize coleoptiles in the presence of natural and synthetic growth regulators. Growth correlations

    Ewa Raczek

    2014-01-01

    Full Text Available The effect of natural (IAA, FC, ABA and synthetic (2,4-D growth substances on the increase of the fresh weight of maize coleoptile segments and change of the pH of the incubation medium, accepted here as criteria of maize coleoptile growth, was studied. The growth of maize coleoptiles depended on the concentration of the growth substances, as well as, on the composition of the incubation medium. The highest stimulation of coleoptile growth was seen with FC at a concentration of 10-4M, whereas ABA at 10-3 M gave the highest inhibition of maize coleoptile fresh weight increase and caused alkalization of the medium. The presence of K+ ions in the incubation medium enhanced the stimulatory effect of IAA and FC on the increase of the coleoptile fresh weight, whereas the presence of these ions and phosphate buffer abolished the growth-promoting effect of IAA and FC. The best correlation of the "fresh weight" and "pH" effects was found in the case of the growth of maize coleoptiles in the presence of FC (rxy = 0.67. The inhibition of maize coleoptile growth in the presence of high concentrations of IAA can be explained by the destructive effect of natural auxin at these concentrations on the integrity of mitochondrial membranes, and therefore on the normal functioning of mitochondria.

  16. The relative value of growth.

    Mass, Nathaniel J

    2005-04-01

    Most executives would say that adding a point of growth and gaining a point of operating-profit margin contribute about equally to shareholder value. Margin improvements hit the bottom line immediately, while growth compounds value over time. But the reality is that the two are rarely equivalent. Growth often is far more valuable than managers think. For some companies, convincing the market that they can grow by just one additional percentage point can be worth six, seven, or even ten points of margin improvement. This article presents a new strategic metric, called the relative value of growth (RVG), which gives managers a clear picture of how growth projects and margin improvement initiatives affect shareholder value. Using basic balance sheet and income sheet data, managers can determine their companies' RVGs, as well as those of their competitors. Calculating RVGs gives managers insights into which corporate strategies are working to deliver value and whether their companies are pulling the most powerful value-creation levers. The author examines a number of well-known companies and explains what their RVG numbers say about their strategies. He reviews the unspoken assumption that growth and profits are incompatible over the long term and shows that a fair number of companies are effective at delivering both. Finally, he explains how managers can use the RVG framework to help them define strategies that balance growth and profitability at both the corporate and business unit levels.

  17. Sociological explanations of economic growth.

    Marsh, R M

    1988-01-01

    Even if questions of how resources are distributed within and between societies are the main concern, it is necessary to continue to grapple with the issue of the causes of economic growth since economic growth and level of development continue to be among the most important causes of inequality, poverty, unemployment, and the quality of life. This paper's dependent variable is the economic growth rate of 55 less developed countries (LDCs) over 2 time periods. 1970-78 and 1965-84. The causal model consists of control variables--level of development and domestic investment in 1965--and a variety of independent variables drawn from major sociological theories of economic growth published during the last 3 decades. Multiple regression analysis shows that, net of the effects of the 2 control variables, the variables which have the strongest effect on economic growth are: 1) direct foreign investment, which has a negative effect, 2) the proportion of the population in military service, and 3) the primary school enrollment ratio, both of which have positive effects on economic growth. On the other hand, variables drawn from some theories receive no empirical support. The mass media of communications, ethnolinguistic heterogeneity, democracy and human rights, income inequality, and state-centric theory's key variable, state strength, all fail to show any significant impact on economic growth rates when the control variables and the significant independent variables are held constant. The theoretical implications of these findings are discussed.

  18. Growth factors and new periodontology

    Paknejad M

    1999-06-01

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

  19. Pro Poor Growth in Cameroon

    Samuel Fambon

    2017-06-01

    Full Text Available The purpose of this paper is to analyze the relationship between economic growth, poverty and income distribution in Cameroon, using both the data derived from three Cameroonian household surveys and the Poverty Equivalent Growth Rate (PEGR methodology developed by Kakwani et al. (2004, The study found that economic growth in Cameroon was pro poor over the period 1996–2007, which suggests that instead of increasing the economic growth rate alone, the poverty equivalent growth rate should also be maximized to achieve the poverty reduction objective, meaning that on the one hand, the growth rate should be boosted, and on the other, the distribution of income should also be concurrently improved. A decomposition of changes in poverty using the Kakwani (1997 approach reveal that the growth component dominates the redistribution component in the reduction of poverty. This suggests that the fall in absolute poverty over the survey period may be attributed to an increase in average household income, and not to the redistributive policies of the government.

  20. Towards Sustainable Growth Business Models

    Kamp-Roelands, N.; Balkenende, J.P.; Van Ommen, P.

    2012-03-15

    The Dutch Sustainable Growth Coalition (DSGC) has the following objectives: The DSGC aims to pro-actively drive sustainable growth business models along three lines: (1) Shape. DSGC member companies aim to connect economic profitability with environmental and social progress on the basis of integrated sustainable growth business models; (2) Share. DSGC member companies aim for joint advocacy of sustainable growth business models both internationally and nationally; and (3) Stimulate. DSGC member companies aim to stimulate and influence the policy debate on enabling sustainable growth - with a view to finding solutions to the environmental and social challenges we are facing. This is their first report. The vision, actions and mission of DSGC are documented in the Manifesto in Chapter 2 of this publication. Chapter 3 contains an overview of key features of an integrated sustainable growth business model and the roadmap towards such a model. In Chapter 4, project examples of DSGC members are presented, providing insight into the hands-on reality of implementing the good practices. Chapter 5 offers an overview of how the Netherlands provides an enabling environment for sustainable growth business models. Chapter 6 offers the key conclusions.

  1. Growth Data - Characterization of Sexual Growth Dimorphism in Sablefish

    National Oceanic and Atmospheric Administration, Department of Commerce — Sexual growth dimorphism (SGD) is a common phenomenon in nature. Numerous marine fishes exhibit SGD, with females often growing faster and attaining larger sizes...

  2. Ghrelin: much more than a hunger hormone

    Ghrelin is a multifaceted gut hormone that activates its receptor, growth hormone secretagogue receptor (GHS-R). Ghrelin's hallmark functions are its stimulatory effects on growth hormone release, food intake and fat deposition. Ghrelin is famously known as the 'hunger hormone'. However, ample recen...

  3. Disruption of PC1/3 expression in mice causes dwarfism and multiple neuroendocrine peptide processing defects

    Zhu, Xiaorong; Zhou, An; Dey, Arunangsu

    2002-01-01

    vertebrates and invertebrates. Disruption of the gene-encoding mouse PC1/3 has now been accomplished and results in a syndrome of severe postnatal growth impairment and multiple defects in processing many hormone precursors, including hypothalamic growth hormone-releasing hormone (GHRH), pituitary...

  4. Juvenile eye growth, when completed?

    Fledelius, Hans C; Christensen, Anders S; Fledelius, Christian

    2014-01-01

    PURPOSE: To test Sorsby's classical statement of axial eye growth as completed at the age of 13 years, with a view also to differentiating between basic eye growth and juvenile elongation associated with eventual refractive change towards myopia. METHODS: (i) A total of 160 healthy eyes close...... about age 13 as general limit found support from the cross-sectional data, which suggested stable emmetropic eye size from about 11-12 years, with an average apparently outgrown male emmetropic value of 23.5 mm versus females' 22.9 mm. The longitudinal data, however, showed emmetropic growth also beyond...

  5. The biophysics of neuronal growth

    Franze, Kristian; Guck, Jochen

    2010-01-01

    For a long time, neuroscience has focused on biochemical, molecular biological and electrophysiological aspects of neuronal physiology and pathology. However, there is a growing body of evidence indicating the importance of physical stimuli for neuronal growth and development. In this review we briefly summarize the historical background of neurobiophysics and give an overview over the current understanding of neuronal growth from a physics perspective. We show how biophysics has so far contributed to a better understanding of neuronal growth and discuss current inconsistencies. Finally, we speculate how biophysics may contribute to the successful treatment of lesions to the central nervous system, which have been considered incurable until very recently.

  6. A Model of Controlled Growth

    Bressan, Alberto; Lewicka, Marta

    2018-03-01

    We consider a free boundary problem for a system of PDEs, modeling the growth of a biological tissue. A morphogen, controlling volume growth, is produced by specific cells and then diffused and absorbed throughout the domain. The geometric shape of the growing tissue is determined by the instantaneous minimization of an elastic deformation energy, subject to a constraint on the volumetric growth. For an initial domain with C}^{2,α boundary, our main result establishes the local existence and uniqueness of a classical solution, up to a rigid motion.

  7. Epitaxial growth of hybrid nanostructures

    Tan, Chaoliang; Chen, Junze; Wu, Xue-Jun; Zhang, Hua

    2018-02-01

    Hybrid nanostructures are a class of materials that are typically composed of two or more different components, in which each component has at least one dimension on the nanoscale. The rational design and controlled synthesis of hybrid nanostructures are of great importance in enabling the fine tuning of their properties and functions. Epitaxial growth is a promising approach to the controlled synthesis of hybrid nanostructures with desired structures, crystal phases, exposed facets and/or interfaces. This Review provides a critical summary of the state of the art in the field of epitaxial growth of hybrid nanostructures. We discuss the historical development, architectures and compositions, epitaxy methods, characterization techniques and advantages of epitaxial hybrid nanostructures. Finally, we provide insight into future research directions in this area, which include the epitaxial growth of hybrid nanostructures from a wider range of materials, the study of the underlying mechanism and determining the role of epitaxial growth in influencing the properties and application performance of hybrid nanostructures.

  8. VT Designated Growth Center Boundary

    Vermont Center for Geographic Information — Growth centers aim to align public infrastructure and private building investments with a local framework of policies and regulations to ensure that 20 years of...

  9. Corruption, Growth, and Public Finances

    Vito Tanzi; Hamid R Davoodi

    2000-01-01

    The paper discusses some channels through which corruption affects growth such as the impact of corruption on enterprises, on the allocation of talent, and on investment. It also discusses the impact of corruption on some aspects of public finance.

  10. The Market for Smart Growth

    Based on several studies of market demand, the authors determined that consumer demand for smart growth would translate into more than 600,000 houses out of the approximately 2 million new housing units built in 2007.

  11. Your Baby's Growth: 5 Months

    ... Safe Videos for Educators Search English Español Your Baby's Growth: 5 Months KidsHealth / For Parents / Your Baby's ... a cause for concern. How Much Will My Baby Grow? By 5 months, your baby's birth weight ...

  12. Investor Protections and Economic Growth

    Haidar, Jamal Ibrahim

    2009-01-01

    Using objective measures of investor protections in 170 countries, I establish that the level of investor protection matters for cross-country differences in GDP growth: countries with stronger protections tend to grow faster than those with poor investor protections.

  13. Traffic fatalities and economic growth

    2003-04-01

    As countries develop death rates usually fall, especially for diseases that affect the young and result in substantial life-years lost. Deaths due to traffic accidents are a notable exception: the growth in motor vehicles that accompanies economic gr...

  14. National Survey of Family Growth

    U.S. Department of Health & Human Services — The National Survey of Family Growth (NSFG) gathers information on family life, marriage and divorce, pregnancy, infertility, use of contraception, and men's and...

  15. Limits to the growth debate

    Gordon, L.

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

  16. Military Expenditure, Threats, and Growth

    Aizenman, Joshua; Glick, Reuven

    2003-01-01

    This paper clarifies one of the puzzling results of the economic growth literature: the impact of military expenditure is frequently found to be non-significant or negative, yet most countries spend a large fraction of their GDP on defense and the military. We start by empirical evaluation of the non- linear interactions between military expenditure, external threats, corruption, and other relevant controls. While growth falls with higher levels of military spending, given the values of the o...

  17. Retail payments and economic growth

    Hasan, Iftekhar; De Renzis, Tania; Schmiedel , Heiko

    2012-01-01

    This paper examines the fundamental relationship between retail payments and overall economic growth. Using data from across 27 European markets over the period 1995–2009, the results confirm that migration to efficient electronic retail payments stimulates overall economic growth, consumption and trade. Among different payment instruments, this relationship is strongest for card payments, followed by credit transfers and direct debits. Cheque payments are found to have a relatively low macro...

  18. Growth, unemployment and wage inertia

    Raurich, Xavier; Sorolla, Valeri

    2014-01-01

    We introduce wage setting via efficiency wages in the neoclassical one-sector growth model to study the growth effects of wage inertia. We compare the dynamic equilibrium of an economy with wage inertia with the equilibrium of an economy without wage inertia. We show that wage inertia affects the long run employment rate and that the transitional dynamics of the main economic variables will be different because wages are a state variable when wage inertia is introduced. In particular, we show...

  19. International Outsourcing and Productivity Growth

    Martin Falk; Yvonne Wolfmayr

    2008-01-01

    This study investigates the impact of international outsourcing to low? and high income countries on total factor productivity growth based on manufacturing industry data for 14 OECD countries from 1995 ? 2000. We find that the broad measure of international outsourcing of material inputs to low income countries is significantly negatively related to productivity growth. Furthermore, while the narrow measure of international outsourcing of materials is not significant, purchased services from...

  20. Human Development and Economic Growth

    Ranis, Gustav

    2004-01-01

    Recent literature has contrasted Human Development, described as the ultimate goal of the development process, with economic growth, described as an imperfect proxy for more general welfare, or as a means toward enhanced human development. This debate has broadened the definitions and goals of development but still needs to define the important interrelations between human development (HD) and economic growth (EG). To the extent that greater freedom and capabilities improve economic performan...

  1. [Saarland Growth Study: sampling design].

    Danker-Hopfe, H; Zabransky, S

    2000-01-01

    The use of reference data to evaluate the physical development of children and adolescents is part of the daily routine in the paediatric ambulance. The construction of such reference data is based on the collection of extensive reference data. There are different kinds of reference data: cross sectional references, which are based on data collected from a big representative cross-sectional sample of the population, longitudinal references, which are based on follow-up surveys of usually smaller samples of individuals from birth to maturity, and mixed longitudinal references, which are a combination of longitudinal and cross-sectional reference data. The advantages and disadvantages of the different methods of data collection and the resulting reference data are discussed. The Saarland Growth Study was conducted for several reasons: growth processes are subject to secular changes, there are no specific reference data for children and adolescents from this part of the country and the growth charts in use in the paediatric praxis are possibly not appropriate any more. Therefore, the Saarland Growth Study served two purposes a) to create actual regional reference data and b) to create a database for future studies on secular trends in growth processes of children and adolescents from Saarland. The present contribution focusses on general remarks on the sampling design of (cross-sectional) growth surveys and its inferences for the design of the present study.

  2. Phenomenology of stochastic exponential growth

    Pirjol, Dan; Jafarpour, Farshid; Iyer-Biswas, Srividya

    2017-06-01

    Stochastic exponential growth is observed in a variety of contexts, including molecular autocatalysis, nuclear fission, population growth, inflation of the universe, viral social media posts, and financial markets. Yet literature on modeling the phenomenology of these stochastic dynamics has predominantly focused on one model, geometric Brownian motion (GBM), which can be described as the solution of a Langevin equation with linear drift and linear multiplicative noise. Using recent experimental results on stochastic exponential growth of individual bacterial cell sizes, we motivate the need for a more general class of phenomenological models of stochastic exponential growth, which are consistent with the observation that the mean-rescaled distributions are approximately stationary at long times. We show that this behavior is not consistent with GBM, instead it is consistent with power-law multiplicative noise with positive fractional powers. Therefore, we consider this general class of phenomenological models for stochastic exponential growth, provide analytical solutions, and identify the important dimensionless combination of model parameters, which determines the shape of the mean-rescaled distribution. We also provide a prescription for robustly inferring model parameters from experimentally observed stochastic growth trajectories.

  3. Placental Adaptations in Growth Restriction

    Zhang, Song; Regnault, Timothy R.H.; Barker, Paige L.; Botting, Kimberley J.; McMillen, Isabella C.; McMillan, Christine M.; Roberts, Claire T.; Morrison, Janna L.

    2015-01-01

    The placenta is the primary interface between the fetus and mother and plays an important role in maintaining fetal development and growth by facilitating the transfer of substrates and participating in modulating the maternal immune response to prevent immunological rejection of the conceptus. The major substrates required for fetal growth include oxygen, glucose, amino acids and fatty acids, and their transport processes depend on morphological characteristics of the placenta, such as placental size, morphology, blood flow and vascularity. Other factors including insulin-like growth factors, apoptosis, autophagy and glucocorticoid exposure also affect placental growth and substrate transport capacity. Intrauterine growth restriction (IUGR) is often a consequence of insufficiency, and is associated with a high incidence of perinatal morbidity and mortality, as well as increased risk of cardiovascular and metabolic diseases in later life. Several different experimental methods have been used to induce placental insufficiency and IUGR in animal models and a range of factors that regulate placental growth and substrate transport capacity have been demonstrated. While no model system completely recapitulates human IUGR, these animal models allow us to carefully dissect cellular and molecular mechanisms to improve our understanding and facilitate development of therapeutic interventions. PMID:25580812

  4. Anticavitation and Differential Growth in Elastic Shells

    Moulton, Derek E.; Goriely, Alain

    2010-01-01

    infinite growth or resorption is imposed at the inner surface of the shell. However, void collapse can occur in a limiting sense when radial and circumferential growth are properly balanced. Growth functions which diverge or vanish at a point arise

  5. Economic growth and gender equality | IDRC - International ...

    And conversely, does gender equality impact economic growth? ... change and growth in the economy on women's employment opportunities and the type ... sectors and their overall effect on development outcomes, such as economic growth ...

  6. Student Augmentation for Crystal Growth Research

    Prasad, V

    1999-01-01

    ... intelligent modeling, design and control of crystal growth processes. One doctoral student worked on integrating the radiation heat transfer model into MASTRAPP, the crystal growth model developed by the Consortium for Crystal Growth Research...

  7. Best practices for rural smart growth.

    2010-07-01

    Smart growth is a development strategy that encompasses economic, environmental and social objectives to manage : the growth of a community. The basic principles of smart growth are to: : Mix land uses. : Take advantage of compact building de...

  8. Growth and Economic Opportunities for Women: Strengthening ...

    Asian outlook: New growth dependent on new productivity. There is no doubt that Canada is tying its future growth prospects to Asia. View moreAsian outlook: New growth dependent on new productivity ...

  9. Understanding "Inclusive Growth": Advancing the global agenda ...

    2013-03-27

    Mar 27, 2013 ... Increasingly, the concept of "inclusive growth," where the benefits of economic growth are ... Growth is less likely to be sustainable with high and/or growing inequalities, and ... A global vision for small business in Egypt.

  10. Nutritionally-Induced Catch-Up Growth

    Galia Gat-Yablonski

    2015-01-01

    Full Text Available Malnutrition is considered a leading cause of growth attenuation in children. When food is replenished, spontaneous catch-up (CU growth usually occurs, bringing the child back to its original growth trajectory. However, in some cases, the CU growth is not complete, leading to a permanent growth deficit. This review summarizes our current knowledge regarding the mechanism regulating nutrition and growth, including systemic factors, such as insulin, growth hormone, insulin- like growth factor-1, vitamin D, fibroblast growth factor-21, etc., and local mechanisms, including autophagy, as well as regulators of transcription, protein synthesis, miRNAs and epigenetics. Studying the molecular mechanisms regulating CU growth may lead to the establishment of better nutritional and therapeutic regimens for more effective CU growth in children with malnutrition and growth abnormalities. It will be fascinating to follow this research in the coming years and to translate the knowledge gained to clinical benefit.

  11. Determinants of economic growth in BRIC countries

    Rajjev K. Goel

    2011-01-01

    We study economic growth in four emerging economies - Brazil, Russia, India, and China (BRIC). Questions addressed are: (a) How do medium term growth determinants differ from short term determinants? (b) What are differences between growth effects of aggregate versus disaggregated exports? And (c) Does lower institutional quality hinder growth? Results show that while BRIC nations have higher growth, there are significant within-group differences. China and Russia mostly showed higher growth,...

  12. Stem secondary growth of tundra shrubs

    Campioli, Matteo; Leblans, Niki; Michelsen, Anders

    2012-01-01

    Our knowledge of stem secondary growth of arctic shrubs (a key component of tundra net primary production, NPP) is very limited. Here, we investigated the impact of the physical elements of the environment on shrub secondary growth by comparing annual growth rates of model species from similar...... growth (stem apical growth, stem length, and apical growth of stem plus leaves), in some cases even with opposite responses. Thus caution should be taken when estimating the impact of the environment on shrub growth from apical growth only. Integration of our data set with the (very limited) previously...

  13. Growth and Predictors of Growth Restraint in Moderately Preterm Children Aged 0 to 4 Years

    Bocca-Tjeertes, I.F.; Kerstjens, J.M.; Reijneveld, S.A.; de Winter, A.F.; Bos, A.F.

    2011-01-01

    OBJECTIVE: To describe growth in moderately preterm-born children, determine the prevalence of growth restraint at the age of 4, and identify predictors of growth restraint. We hypothesized that growth in moderately preterm-born children differs from growth in term-born children and that growth

  14. Green growth in the Netherlands

    Balde, K.; Boelens, A.; Brinksma, E.; Edens, B.; Hiethaar, S.; Klein, P.; Schenau, S.

    2011-04-01

    In 2009 the Ministerial Council Meeting of the Organisation for Economic Co-operation and Development (OECD) committed itself to a green growth strategy. Such a strategy fosters economic growth and development while ensuring that natural resources can continue to provide the ecosystem services on which our well-being relies. It also endorses investment, competition and innovation which will underpin sustained growth and give rise to new economic opportunities. Green growth provides both a policy strategy for implementing this economic transformation and a monitoring framework with a proposed set of indicators. This report presents an overview of the state of green growth in the Netherlands. It should be regarded as a benchmark for a more thorough and comprehensive assessment of green growth in the future. It is based on the set of indicators proposed by the OECD in their intermediate report of February 2011. Data relevant to the Dutch situation are presented for twenty of these indicators, illustrating the observed trends. The indicators are grouped in four themes. For the first theme, environmental efficiency of production, on the whole the indicators show increased efficiency. However, indicators such as greenhouse gas intensity, energy efficiency and material intensity show only relative decoupling, which on its own is not enough to ensure green growth. In addition, the increase in environmental efficiency is partly explained by substitution of imports for domestic production, which is not conducive to green growth on a global scale: the efficiency gains in domestic production, for example, are offset by increases in foreign greenhouse gas emissions. Water use and agricultural nutrient surpluses are the only indicators where absolute decoupling has occurred. The second theme contains indicators regarding the natural assets base. This group of indicators provides a mixed picture. Natural gas reserves are decreasing and the overall level of threat to animal

  15. Phytochrome, plant growth and flowering

    King, R. W.; Bagnall, D. J.

    1994-01-01

    Attempts to use artificially lit cabinets to grow plants identical to those growing in sunlight have provided compelling evidence of the importance of light quality for plant growth. Changing the balance of red (R) to far-red (FR) radiation, but with a fixed photosynthetic input can shift the phytochrome photoequilibrium in a plant and generate large differences in plant growth. With FR enrichment the plants elongate, and may produce more leaf area and dry matter. Similar morphogenic responses are also obtained when light quality is altered only briefly (15-30 min) at the end-of-the-day. Conversely, for plants grown in natural conditions the response of plant form to selective spectral filtering has again shown that red and far-red wavebands are important as found by Kasperbauer and coworkers. Also, where photosynthetic photon flux densities (PPFD) of sunlight have been held constant, the removal of far-red alone alters plant growth. With FR depletion plants grown in sunlight are small, more branched and darker green. Here we examine the implications for plant growth and flowering when the far-red composition of incident radiation in plant growth chambers is manipulated.

  16. Universality in stochastic exponential growth.

    Iyer-Biswas, Srividya; Crooks, Gavin E; Scherer, Norbert F; Dinner, Aaron R

    2014-07-11

    Recent imaging data for single bacterial cells reveal that their mean sizes grow exponentially in time and that their size distributions collapse to a single curve when rescaled by their means. An analogous result holds for the division-time distributions. A model is needed to delineate the minimal requirements for these scaling behaviors. We formulate a microscopic theory of stochastic exponential growth as a Master Equation that accounts for these observations, in contrast to existing quantitative models of stochastic exponential growth (e.g., the Black-Scholes equation or geometric Brownian motion). Our model, the stochastic Hinshelwood cycle (SHC), is an autocatalytic reaction cycle in which each molecular species catalyzes the production of the next. By finding exact analytical solutions to the SHC and the corresponding first passage time problem, we uncover universal signatures of fluctuations in exponential growth and division. The model makes minimal assumptions, and we describe how more complex reaction networks can reduce to such a cycle. We thus expect similar scalings to be discovered in stochastic processes resulting in exponential growth that appear in diverse contexts such as cosmology, finance, technology, and population growth.

  17. Phytochrome, plant growth and flowering

    King, R.W.; Bagnall, D.J. [CSIRO, Canberra (Australia)

    1994-12-31

    Attempts to use artificially lit cabinets to grow plants identical to those growing in sunlight have provided compelling evidence of the importance of light quality for plant growth. Changing the balance of red (R) to far-red (FR) radiation, but with a fixed photosynthetic input can shift the phytochrome photoequilibrium in a plant and generate large differences in plant growth. With FR enrichment the plants elongate, and may produce more leaf area and dry matter. Similar morphogenic responses are also obtained when light quality is altered only briefly (15-30 min) at the end-of-the-day. Conversely, for plants grown in natural conditions the response of plant form to selective spectral filtering has again shown that red and far-red wavebands are important as found by Kasperbauer and coworkers. Also, where photosynthetic photon flux densities (PPFD) of sunlight have been held constant, the removal of far-red alone alters plant growth. As shown for chrysanthemum, with FR depletion plants grown in sunlight are small, more branched and darker green. We examine the implications for plant growth and flowering when the far-red composition of incident radiation in plant growth chambers is manipulated.

  18. American growth and Napoleonic Wars

    Vergil Hasan

    2013-01-01

    Full Text Available Four years after the French Revolution, in 1793 a series of wars among France and other major powers of Europe began and they lasted until 1815. There is disagreement among economic historians about the effects of these wars on the trend of US economic growth. This paper aims to answer the following question. Did America as a neutral nation take advantage of economic possibilities caused by Europe at war through trade? To put it differently, this paper questions whether there was an export-led growth due to the war. To answer this question, we re-examined the export-led growth hypothesis for the period 1790-1860 using the ARDL methodology. Based on this methodology, a cointegrated relationship is found among the variables of real GDP, labor, exports and exchange rates. The results suggest that the economic growth of the US was not export-driven. In addition, parallel to the results of unit root tests with structural breaks, the coefficient of the dummy variable was statistically significant in the long run, implying that the war did have a significant effect on the economic growth trend of the US.

  19. SME Cooperation on Innovation & Growth

    Brink, Tove; Neville, Mette

    2016-01-01

    The research in this paper reveals how cooperation of SMEs can enable innovation and growth. The research is conducted in a four-year period with 24 SMEs participating from different industry branches. The research is now in the late part of the 3rd. year starting in 2013 and finished January 2017....... Preliminary findings are revealed here and discussed with the SMEs. Shorter-term cooperation and especially longer-term collaboration is important for SMEs to enable innovation and growth. The content of collaboration is based on the cross-disciplinary trinity of organisational- and managerial development......, business model development and financial development. The trinity requires time to get the specific insight on application for each SME. An enhanced contribution is made to the field of SMEs, to academia and to public bodies to understand the needed initiatives to support SMEs for innovation and growth...

  20. Filamentous Growth in Eremothecium Fungi

    Oskarsson, Therese

    , this thesis deals with some of the aspects of hyphal growth, which is an important virulence factor for pathogenic fungi infecting both humans and plants. Hyphal establishment through continuous polar growth is a complex process, requiring the careful coordination of a large subset of proteins involved......-regulatory activity of AgGts1, the protein could have additional actin organizing properties. In the second and third part, this thesis addresses the use of A. gossypii and its relative E. cymbalariae as model organisms for filamentous growth. A series of assays analyzed the capability of Eremothecium genus fungi...... of molecular tools for E. cymbalariae to enable a faster and more efficient approach for genetic comparisons between Eremothecium genus fungi....

  1. Energy consumption and economic growth

    Brookes, L G

    1972-10-01

    A mathematical model relating Gross National Product (GNP) per capita to useful energy consumed per capita is demonstrated to predict the shift in this relationship actually experienced in the U.K. and the U.S. over a period of years. World GNP growths in the recent past are used to forecast GNP growth to the year 2030 and also (via the model) the necessary fuel consumption for such growth; likewise, potential production of fossil fuels (exclusive of tar sands and oil shale) is shown to 2030, based on two different assumptions about total world reserves. Fossil fuel ceases to meet world requirements for energy at some time between 1985 and 1995. The most likely candidate for filling the gap is nuclear power.

  2. Employment growth and regional development

    Eriksson, Rikard; Hansen, Høgni Kalsø; Winther, Lars

    2017-01-01

    This paper explores the potential drivers behind uneven regional development in the context of employment growth in Denmark and Sweden. In particular, we are interested in the roles of urbanization, industrial change and the rise of the new economy as manifested in the growth of the two economies...... in 2002–2007. The aim of this paper is, therefore, to analyse the impact of a number of key industrial sectors on regional employment growth in the two countries. The empirical analysis is based on longitudinal matched employer–employee data retrieved from official registers in each economy from 2002...... economies, we find that, although in general these economies react relatively similarly to changes, embarking on a narrower analysis of the individual sectors reveals marked national differences. This indicates that context matters in the analysis of regional economic dynamics in terms of structure, system...

  3. Nerve growth factor promotes human hemopoietic colony growth and differentiation

    Matsuda, H.; Coughlin, M.D.; Bienenstock, J.; Denburg, J.A.

    1988-01-01

    Nerve growth factor (NGF) is a neurotropic polypeptide necessary for the survival and growth of some central neurons, as well as sensory afferent and sympathetic neurons. Much is now known of the structural and functional characteristics of NGF, whose gene has recently been clones. Since it is synthesized in largest amounts by the male mouse submandibular gland, its role exclusively in nerve growth is questionable. These experiments indicate that NGF causes a significant stimulation of granulocyte colonies grown from human peripheral blood in standard hemopoietic methylcellulose assays. Further, NGF appears to act in a relatively selective fashion to induce the differentiation of eosinophils and basophils/mast cells. Depletion experiments show that the NGF effect may be T-cell dependent and that NGF augments the colony-stimulating effect of supernatants from the leukemic T-cell (Mo) line. The hemopoietic activity of NGF is blocked by 125 I-polyclonal and monoclonal antibodies to NGF. The authors conclude that NGF may indirectly act as a local growth factor in tissues other than those of the nervous system by causing T cells to synthesize or secrete molecules with colony-stimulating activity. In view of the synthesis of NGF in tissue injury, the involvement of basophils/mast cells and eosinophils in allergic and other inflammatory processes, and the association of mast cells with fibrosis and tissue repair, they postulate that NGF plays an important biological role in a variety of repair processes

  4. Surfactant-Mediated Growth Revisited

    Meyerheim, H. L.; Sander, D.; Popescu, R.; Pan, W.; Kirschner, J.; Popa, I.

    2007-01-01

    The x-ray structure analysis of the oxygen-surfactant-mediated growth of Ni on Cu(001) identifies up to 0.15 monolayers of oxygen in subsurface octahedral sites. This questions the validity of the general view that surfactant oxygen floats on top of the growing Ni film. Rather, the surfactant action is ascribed to an oxygen-enriched zone extending over the two topmost layers. Surface stress measurements support this finding. Our results have important implications for the microscopic understanding of surfactant-mediated growth and the change of the magnetic anisotropy of the Ni films

  5. Monitoring crack growth using thermography

    Djedjiga, Ait Aouita; Abdeldjalil, Ouahabi

    2008-01-01

    The purpose of this work is to present a novel strategy for real-time monitoring crack growth of materials. The process is based on the use of thermal data extracted along the horizontal axis of symmetry of single edge notch tension (SENT) specimens, during fatigue tests. These data are exploited using an implemented program to detect in situ the growth of fatigue crack, with the critical size and propagation speed of the crack. This technique has the advantage to be applicable to a wide range of materials regardless of their electrical conductivity and their surface texture. (authors)

  6. Innovation, resources and economic growth

    Curzio, A.Q.; Fortis, M.; Zoboli, R.

    1994-01-01

    The book is concerned with the following items: 1. Technological Creativity and Institutions, 2. Innovation at Work in an Historical-Economic Perspective: Energy and Industrial Materials, 3. Scientific Revolutions and Strategies of Economic Supremacy: Advanced Materials and Biotechnologies, 4. Economic Growth and Agro-Food Policies in Key Problem Regions: Former USSR and LDCs, 5. Economic Growth and Natural Resources at Risk: Climate Change, Forests and Water and in Conclusion: Innovation and Resources in a Global Policy Perspective. Only one chapter have regard to energy problems: Energie efficient technologies: past and future perspectives. (UA)

  7. The gendered politics of growth

    Neergaard, Helle; Bøllingtoft, Anne

    Based on a review of existing research on growth and gender, this paper challenges the traditional financial and economic assumptions about new venture growth. It proposes that there are numerous ways in which a new venture may 'grow' other than growing the business organically and that women...... simply choose other strategic avenues for growing their business that do not produce performance data measurable in traditional ways. Nevertheless, they contribute considerably to turning the wheels of the economy, wherefore it is necessary to produce an understanding of their choices which goes beyond...

  8. The Simplest Unified Growth Theory

    Strulik, Holger; Weisdorf, Jacob Louis

    This paper provides a unified growth theory, i.e. a model that explains the very long-run economic and demographic development path of industrialized economies, stretching from the pre-industrial era to present-day and beyond. Making strict use of Malthus' (1798) so-called preventive check...... hypothesis - that fertility rates vary inversely with the price of food - the current study offers a new and straightforward explanation for the demographic transition and the break with the Malthusian era. The current framework lends support to existing unified growth theories and is well in tune...

  9. Growth Factors and Tension-Induced Skeletal Muscle Growth

    Vandenburgh, Herman H.

    1994-01-01

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

  10. When economic growth is less than exponential

    Groth, Christian; Koch, Karl-Josef; Steger, Thomas

    2010-01-01

    This paper argues that growth theory needs a more general notion of "regularity" than that of exponential growth. We suggest that paths along which the rate of decline of the growth rate is proportional to the growth rate itself deserve attention. This opens up for considering a richer set...

  11. When Economic Growth is Less than Exponential

    Groth, Christian; Koch, Karl-Josef; Steger, Thomas M.

    This paper argues that growth theory needs a more general notion of "regularity" than that of exponential growth. We suggest that paths along which the rate of decline of the growth rate is proportional to the growth rate itself deserve attention. This opens up for considering a richer set...

  12. The Growth Opportunity Channel of Debt Structure

    Giambona, E.; Golec, J.

    2013-01-01

    This paper studies the importance of growth opportunities for debt structure decisions. High growth firms use more unsecured debt to preserve financial flexibility (in the form of untapped secured debt capacity) in connection with future growth opportunities: the growth opportunity channel of debt

  13. Nonlinear Growth Curves in Developmental Research

    Grimm, Kevin J.; Ram, Nilam; Hamagami, Fumiaki

    2011-01-01

    Developmentalists are often interested in understanding change processes, and growth models are the most common analytic tool for examining such processes. Nonlinear growth curves are especially valuable to developmentalists because the defining characteristics of the growth process such as initial levels, rates of change during growth spurts, and…

  14. The relative volume growth of minimal submanifolds

    Markvorsen, Steen; Palmer, V.

    2002-01-01

    The volume growth of certain well-defined subsets of minimal submanifolds in riemannian spaces are compared with the volume growth of balls and spheres ill space forms of constant curvature.......The volume growth of certain well-defined subsets of minimal submanifolds in riemannian spaces are compared with the volume growth of balls and spheres ill space forms of constant curvature....

  15. Energy, economic growth, and human welfare

    Schurr, S.H.

    1984-01-01

    The subject is covered in sections, entitled: economic growth and human welfare; world-wide economic growth; economic growth and energy consumption; assessing the future; caution advised; energy supply and economic growth; supply as constraint; sound policies needed. (U.K.)

  16. Obesity, growth hormone and weight loss

    Rasmussen, Michael Højby

    2009-01-01

    Growth hormone (GH) is the most important hormonal regulator of postnatal longitudinal growth in man. In adults GH is no longer needed for longitudinal growth. Adults with growth hormone deficiency (GHD) are characterised by perturbations in body composition, lipid metabolism, cardiovascular risk...

  17. Understanding "Inclusive Growth": Advancing the global agenda ...

    27 mars 2013 ... Increasingly, the concept of "inclusive growth," where the benefits of economic growth are enjoyed across societies, is being recognized and advanced by many countries. Growth is less likely to be sustainable with high and/or growing inequalities, and inequality can hamper growth.

  18. Evaluating growth performance of young stands

    A. L. Roe; R. E. Benson

    1966-01-01

    A simple procedure for evaluating the diameter growth of young stands in relation to potential growth is described. A comparison technique is developed which contrasts relative diameter of crop trees to the relative diameter growth of the last decade to show the condition and trend of growth in the stand. The method is objective, easy to use, and has several...

  19. Homeorhetic hormones, metabolites and accelerated growth ...

    Blood samples were drawn from surgically implanted catheters in the caudal aorta and vena cava during normal growth, maintenance (zero) growth and accelerated growth.These samples were assayed for glucose, free fatty acids, glycerol, alanine, lysine, growth hormone, insulin and thyroxine. It was found that during the ...

  20. Fibroblast growth factor receptors in breast cancer.

    Wang, Shuwei; Ding, Zhongyang

    2017-05-01

    Fibroblast growth factor receptors are growth factor receptor tyrosine kinases, exerting their roles in embryogenesis, tissue homeostasis, and development of breast cancer. Recent genetic studies have identified some subtypes of fibroblast growth factor receptors as strong genetic loci associated with breast cancer. In this article, we review the recent epidemiological findings and experiment results of fibroblast growth factor receptors in breast cancer. First, we summarized the structure and physiological function of fibroblast growth factor receptors in humans. Then, we discussed the common genetic variations in fibroblast growth factor receptors that affect breast cancer risk. In addition, we also introduced the potential roles of each fibroblast growth factor receptors isoform in breast cancer. Finally, we explored the potential therapeutics targeting fibroblast growth factor receptors for breast cancer. Based on the biological mechanisms of fibroblast growth factor receptors leading to the pathogenesis in breast cancer, targeting fibroblast growth factor receptors may provide new opportunities for breast cancer therapeutic strategies.

  1. Advanced bone age as an indicator facilitates the diagnosis of precocious puberty

    Yue-Qin Xu

    Full Text Available Abstract Objective: Diagnosis of central precocious puberty has always been challenging in clinical practice. As an important method in the diagnosis of central precocious puberty, luteinizing hormone-releasing hormone stimulation test is complex and time-consuming. In many cases, clinical traits are inconsistent with luteinizing hormone-releasing hormone stimulation test results, therefore not reliable for diagnosis. In this study, the authors intended to find an indicator that predicts the results of the luteinizing hormone-releasing hormone stimulation test among subjects with early pubertal signs. Methods: Cases of 382 girls with early breast development before 8 years old and luteinizing hormone-releasing hormone stimulation test before 9 years old were included and underwent follow-up tests. Patients with peak luteinizing hormone level ≥5 IU/L were considered positive in the luteinizing hormone-releasing hormone stimulation test. Anthropometric data, body mass index, bone age evaluation, blood hormones levels of luteinizing hormone, estradiol, follicle-stimulating hormone, and uterine and ovarian volumes were analyzed. Results: Subjects with positive results in the initial test demonstrated early bone maturation, accelerated growth, and elevated basal blood luteinizing hormone, estradiol, and follicle-stimulating hormone levels, when compared with subjects with negative results in the initial test. Subjects with positive results in the follow-up test presented a more advanced bone age and more accelerated linear growth, when compared with subjects with negative results in the follow-up test. Conclusions: According to the statistical analysis, advanced bone age is the most effective predictor of the result of luteinizing hormone-releasing hormone stimulation test.

  2. Emittance growth in rf linacs

    Jameson, R.A.

    1979-01-01

    As the space-charge limit is approached, the current that can be accelerated in an rf linac and the output emittance that can be expected are discussed. The role of the envelope equations to estimate limits is outlined. The results of numerical experiments to explore general properties of emittance growth are given

  3. Exhaustible resources and economic growth

    Campbell, H.F.

    1984-09-01

    This study examines the effect of a booming natural resource sector on regional economic growth, with particular attention to the impact of regional government policy on mineral rent taxation and the allocation of resource revenues. The author's approach is first to document the relevant theory and then apply it to the case of the uranium industry in Saskatchewan

  4. Knowledge Spillovers and Economic Growth

    A.J. van Stel (André); H.R. Nieuwenhuijsen

    2002-01-01

    textabstractThe importance of knowledge spillovers for achieving innovation and economic growth is widely recognized. It is not straightforward which type of spillovers is most effective: intra-sectoral spillovers or inter-sectoral spillovers. We investigate this controversy using a model of

  5. Intrauterine growth restriction - part 2.

    Sharma, Deepak; Farahbakhsh, Nazanin; Shastri, Sweta; Sharma, Pradeep

    2016-12-01

    Small for gestational age (SGA) infants have been classically defined as having birth weight less than two standard deviations below the mean or less than the 10th percentile of a population-specific birth weight for specific gestational age, whereas intrauterine growth restriction (IUGR) has been defined as a rate of foetal growth that is less than normal for the population and for the growth potential of a specific infant. SGA infants have more frequent problems such as perinatal asphyxia, hypothermia, hypoglycaemia, polycythaemia and many more when compared with their appropriate for gestational age counterpart. They too have growth retardation and various major and subtle neurodevelopmental handicaps, with higher rates of perinatal and neonatal mortality. With the advent of newer technologies, even though the perinatal diagnosis of these SGA/IUGR foetuses has increased, but still perinatal morbidity and mortality rates are higher than normal foetuses and infants. In this part, we have covered neonatal IUGR classification, postnatal diagnosis, short-term and long-term complications faced by these IUGR infants.

  6. Effective growth paths for SMEs

    Wakkee, I.A.M.; van der Veen, M.; Eurlings, W.

    2015-01-01

    How firms grow forms a key question in the research on small and medium-sized enterprises (SMEs). Based on a survey amongst 1,535 SMEs, we show that the presence of growth capability factors, such as, innovation capacity, financing capacity and human capital, offers inadequate explanation for

  7. Globalization and limit to growth

    Gros, D.

    2009-01-01

    A global financial crisis is not the only concern the world should have. From oil and other commodities new challenges arise, that could be difficult to face properly and could provide another limit to growth. This Malthusian feature of the 21. century emerges clearly if one focuses on climate change. [it

  8. Growth and photosynthesis of lettuce

    Holsteijn, van H.M.C.

    1981-01-01

    Butterhead lettuce is an important glass-house crop in the poor light period in The Netherlands. Fundamental data about the influence of temperature, light and CO 2 on growth and photosynthesis are important e.g. to facilitate selection criteria for new cultivars. In

  9. Financial Liberalization and Economic Growth

    Bumann, S.; Hermes, N.; Lensink, B.W.

    2013-01-01

    This study provides a systematic analysis of the empirical literature on the relationship between financial liberalization and economic growth by conducting a meta-analysis, based on 441 t-statistics reported in 60 empirical studies. We focus on explaining the heterogeneity of results in our sample

  10. Dynamic dewetting through micropancake growth

    Seddon, James Richard Thorley; Bliznyuk, O.; Bliznyuk, Olesya; Kooij, Ernst S.; Poelsema, Bene; Zandvliet, Henricus J.W.; Lohse, Detlef

    2010-01-01

    We experimentally investigate the dynamics of nanometer-high, micrometer-wide gassy layers at the interface between a hydrophobic solid and bulk water. These micropancakes grow laterally in time, on the timescale of an hour, leading to partial dewetting of the solid. The growth is directional,

  11. Numerical prediction of rose growth

    Bernsen, E.; Bokhove, Onno; van der Sar, D.M.

    2006-01-01

    A new mathematical model is presented for the prediction of rose growth in a greenhouse. Given the measured ambient environmental conditions, the model consists of a local photosynthesis model, predicting the photosynthesis per unit leaf area, coupled to a global greenhouse model, which predicts the

  12. Intangible capital and economic growth

    Chen, Wen

    2016-01-01

    Modern economic growth stems in good part from investments in knowledge-based intangible assets, such as research and development (R&D), organisational know-how, product design, branding and marketing. By capitalising expenditures on these intangibles as business investments, this thesis

  13. Cultural diversity and economic growth

    Ager, Philipp; Brückner, Markus

    2013-01-01

    We exploit the large inflow of immigrants to the US during the 1870–1920 period to examine the effects that within-county changes in the cultural composition of the US population had on output growth. We construct measures of fractionalization and polarization to distinguish between the different...

  14. Growth of the zebrafish heart

    de Pater, E.M.

    2010-01-01

    Outline of this thesis In order to find new genetic factors, which are involved in cardiac growth we performed a forward genetic screen and we report the outcome of this screen in chapter 2. We screened at 5 days post fertilization (dpf) for mutants with either an enlarged heart or reduced heart

  15. Mudcake growth: Model and implications

    Liu, Q.; Santamarina, Carlos

    2017-01-01

    cementing, and to prevent partial differential sticking. We developed a robust mud cake growth model for water-based mud based on wide stress-range constitutive equations within a Lagrangian reference system to avoid non-natural moving boundary solutions

  16. Growth charts of human development

    Van Buuren, Stef

    2014-01-01

    This article reviews and compares two types of growth charts for tracking human development over age. Both charts assume the existence of a continuous latent variable, but relate to the observed data in different ways. The D-score diagram summarizes developmental indicators into a single aggregate

  17. Employment Growth and International Trade

    Ibsen, Rikke; Warzynski, Frederic; Westergård-Nielsen, Niels Chr.

    In this paper, we use a detailed dataset containing information about all international trade transactions of the population of Danish ?rms over more than a decade to analyze the relationship between export and import decisions and employment growth. We further distinguish between imports of ?nal...

  18. Stochastic theory of grain growth

    Hu Haiyun; Xing Xiusan.

    1990-11-01

    The purpose of this note is to set up a stochastic theory of grain growth and to derive the statistical distribution function and the average value of the grain radius so as to match them with the experiment further. 8 refs, 1 fig

  19. Multimodel ensembles of wheat growth

    Martre, Pierre; Wallach, Daniel; Asseng, Senthold

    2015-01-01

    , but such studies are difficult to organize and have only recently begun. We report on the largest ensemble study to date, of 27 wheat models tested in four contrasting locations for their accuracy in simulating multiple crop growth and yield variables. The relative error averaged over models was 24...

  20. Growth with Time Zone Differences

    Toru Kikuchi; Sugata Marjit

    2010-01-01

    We propose a two-country growth model of intermediate business-services trade that captures the role of time zone differences. It is shown that a time-saving improvement in intermediate business-services trade involving production in different time zones can have a permanent impact on productivity.

  1. Growth Pattern of Atherosclerotic Calcifications

    Larsen, Lene Lillemark; Ganz, Melanie; Dam, Erik

    2008-01-01

    of the calcifications are matched longitudinally using thin plate spline registration and area overlap calculations. The growth of the calcifications is measured by the distribution of the geometry statistics of the calcifications. The method was evaluated on 135 subjects with a total number of 611 calcifications. Our...

  2. Carboxydotrophic growth of Geobacter sulfurreducens

    Geelhoed, J.S.; Henstra, A.M.; Stams, A.J.M.

    2016-01-01

    This study shows that Geobacter sulfurreducens grows on carbon monoxide (CO) as electron donor with fumarate as electron acceptor. Geobacter sulfurreducens was tolerant to high CO levels, with up to 150 kPa in the headspace tested. During growth, hydrogen was detected in very slight amounts (∼5

  3. Modeling Population Growth and Extinction

    Gordon, Sheldon P.

    2009-01-01

    The exponential growth model and the logistic model typically introduced in the mathematics curriculum presume that a population grows exclusively. In reality, species can also die out and more sophisticated models that take the possibility of extinction into account are needed. In this article, two extensions of the logistic model are considered,…

  4. Growth Enterprise Board on Track

    2008-01-01

    @@ In Premier Wen Jiabao's Government Work Report to the NPC,he said,"China will establish a stock market for high growth enterprises this year,accelerate development of the bond market and steadily develop the futures market."But he didn't layout a fixed timetable.

  5. Simulating the growth of tafoni

    Huinink, H.P.; Pel, L.; Kopinga, K.

    2004-01-01

    Throughout the world, large caves in rocks (tafoni) are found, which originate from salt weathering. The mechanisms that control their development are poorly understood. The growth of tafoni has been studied with a model that describes how a rock surface, containing a small pit, disintegrates by

  6. Two-sector disequilibrium growth

    J.G.M. van Marrewijk (Charles); J.B.L.M. Verbeek (Jos)

    1994-01-01

    textabstractWe investigate the effects of (i) profit distribution to either laborers or capital-owners, (ii) sector-specific or efficient rationing schemes, and (iii) government consumption in a two-sector disequilibrium growth model with sluggish real wage rate adjustment (which affects capital

  7. The Growth Opportunities For SMC?

    Madsen, Erik Strøjer; Smith, Valdemar; Bentzen, Jan Børsen

    2006-01-01

    The extensive empirical literature on the validity of Gibrat's law does not in general verify the law as it finds that firms' growth rates are negatively correlated with both firm size and age. However, some studies find that Gibrat's law holds for sub-samples of firms such as large firms or firms...

  8. Ketogenic Diet: Effects on Growth

    J Gordon Millichap

    2002-12-01

    Full Text Available The effects of the ketogenic diet on growth of 237 children (130 males, 107 females treated for intractable epilepsy has been evaluated in a prospective cohort study (average follow-up 308 days at the Johns Hopkins Hospital, Baltimore, MD.

  9. Height Growth of Mahogany Seedlings

    C. B. Briscoe; R. W. Nobles

    1962-01-01

    Since the recognition of natural hybridization of small-leaf (West Indies) mahogany (Swietenia mahagoni Jacq.) with bigleaf (Honduras) mahogany (S. macrophylla King) there has been conjecture about their relative growth rates. One would expect small-leaf to be the fastest growing on dry sites, the hybrids to be fastest on intermediate sites, and bigleaf to excel on wet...

  10. Model uncertainty in growth empirics

    Prüfer, P.

    2008-01-01

    This thesis applies so-called Bayesian model averaging (BMA) to three different economic questions substantially exposed to model uncertainty. Chapter 2 addresses a major issue of modern development economics: the analysis of the determinants of pro-poor growth (PPG), which seeks to combine high

  11. ECONOMIC gROWTH, GLOBALIZATION AND TRADE

    Nuno Carlos LEITÃO

    2012-01-01

    The purpose of this article is to investigate the relationship between economic growth, globalization and trade. The manuscript uses the assumptions of the economic growth exogenous and endogenous models. It introduces new proxies for explain the economic growth as in intra-industry trade, foreign direct investment and globalization index. The results indicate that economic growth is a dynamic process. The intra-industry has a positive impact on economic growth. This paper confirms relevan...

  12. Money and Growth: An Alternative Approach.

    Ireland, Peter N

    1994-01-01

    This paper takes an alternative approach to the topic of money and growth by developing a model in which the effects of sustained capital accumulation on an evolving system of payments, in addition to the conventional effects of sustained inflation on growth, are examined. While the effects of inflation on growth are small, the effects of growth on the monetary system are substantial. The results are consistent with ideas about money and growth contained in work that predates that of James To...

  13. Cointegration growth, poverty and inequality in Sudan

    Mohamed Hassan, Hisham

    2008-01-01

    This analytical review explores the links between growth, poverty and inequality in Sudan for the period 1956-2003. This paper build upon different models to investigate empirically the relationship between economic growth - as measured by GDP per capita growth- and inequality as measured by Gini coefficient (the growth, inequality and poverty triangle hypotheses), using data from the national and international sources. The paper tries to answer the following questions: i) whether growth, ine...

  14. Is Urban Economic Growth Inclusive in India?

    Tripathi, Sabyasachi

    2013-01-01

    This paper measures the overall inclusive growth of a city by considering changing trends in the key economic variables based on ‘Borda ranking’ and establishes a relationship between city economic growth and overall city inclusive growth. By using data of 52 large cities in India, this paper finds that higher urban economic growth is associated with an increase in urban inequality, a reduction in urban poverty, and a lower level of overall inclusive growth of a city.

  15. Education Vouchers, Growth and Income Inequality

    Buly A Cardak

    2004-01-01

    This paper uses a growth model with public and private education alternatives to investigate the implications of education voucher for economic growth and the evolution of income inequality. The results indicate that introducing education vouchers can increase economic growth. families that switch from public to private education due to vouchers experience higher incomes, leading to growth in the tax base which in turn raises public education expenditures and increases the growth of the whole...

  16. Ellipsometry of anodic film growth

    Smith, C.G.

    1978-08-01

    An automated computer interpretation of ellisometer measurements of anodic film growth was developed. Continuous mass and charge balances were used to utilize more fully the time dependence of the ellipsometer data and the current and potential measurements. A multiple-film model was used to characterize the growth of films which proceeds via a dissolution--precipitation mechanism; the model also applies to film growth by adsorption and nucleation mechanisms. The characteristic parameters for film growth describe homogeneous and heterogeneous crystallization rates, film porosities and degree of hydration, and the supersaturation of ionic species in the electrolyte. Additional descriptions which may be chosen are patchwise film formation, nonstoichiometry of the anodic film, and statistical variations in the size and orientation of secondary crystals. Theories were developed to describe the optical effects of these processes. An automatic, self-compensating ellipsometer was used to study the growth in alkaline solution of anodic films on silver, cadmium, and zinc. Mass-transport conditions included stagnant electrolyte and forced convection in a flow channel. Multiple films were needed to characterize the optical properties of these films. Anodic films grew from an electrolyte supersatuated in the solution-phase dissolution product. The degree of supersaturation depended on transport conditions and had a major effect on the structure of the film. Anodic reaction rates were limited by the transport of charge carriers through a primary surface layer. The primary layers on silver, zinc, and cadmium all appeared to be nonstoichiometric, containing excess metal. Diffusion coefficients, transference numbers, and the free energy of adsorption of zinc oxide were derived from ellipsometer measurements. 97 figures, 13 tables, 198 references.

  17. Growth hormone and the heart.

    Cittadini, A; Longobardi, S; Fazio, S; Saccà, L

    1999-01-01

    Until a few years ago, growth hormone (GH) and insulin-like growth factor-1 (IGF-1) were considered essential only to the control of linear growth, glucose homeostasis, and for the maintenance of skeletal muscle mass. A large body of evidence recently coming from animal and human studies has unequivocally proven that the heart is a target organ for the GH/IGF-1 axis. Specifically GH exerts both direct and indirect cardiovascular actions. Among the direct effects, the ability of GH to trigger cardiac tissue growth plays a pivotal role. Another direct effect is to augment cardiac contractility, independent of myocardial growth. Direct effects of GH also include the improvement of myocardial energetics and mechanical efficiency. Indirect effects of GH on the heart include decreased peripheral vascular resistance (PVR), expansion of blood volume, increased glomerular filtration rate, enhanced respiratory activity, increased skeletal muscle performance, and psychological well-being. Among them, the most consistently found is the decrease of PVR. GH may also raise preload through its sodium-retaining action and its interference with the hormonal system that regulates water and electrolyte metabolism. Particularly important is the effect of GH on skeletal muscle mass and performance. Taking into account that heart failure is characterized by left ventricular dilation, reduced cardiac contractility, and increase of wall stress and peripheral vascular resistance, GH may be beneficial for treatment of heart failure. Animal studies and preliminary human trials have confirmed the validity of the GH approach to the treatment of heart failure. Larger placebo-controlled human studies represent the main focus of future investigations.

  18. Canada's population: growth and dualism.

    Beaujot, R P

    1978-04-01

    In Canada the current 1.3% population growth rate is causing some concern. Those concerned argue that such a rate of growth in combination with high levels of consumption could jeopardize the country's resource base and its comfortable style of living. Many Canadians are questioning high levels of immigration, for now that the fertility level is below replacement level, net immigration contributes substantially to population growth (over 1/3 in 1976). The growing proportion of non-Europeans among recent immigrants is causing resentment, and, in a tight job market, immigrants are regarded as threats to the World War 2 baby boom cohort who are now at working ages. The baby boom generation also puts stress on housing and health services, and it will increase the need for pension checks as it ages. Although French fertility is no longer high and immigration is no longer dominated by the British, the French group's 200-year struggle to preserve its identity continues on in the current effort of the Quebec government to enforce the use of French language by law within that province. Geography and climate dictate another demographic fact that divides the country and pervades its history. In addition to intense regionalism, uneven population distribution is responsible for 2 other concerns: the rapid growth of several already large cities and depopulation of many small communities. Focus in this discussion is on Canada's population growth in the past and as projected for the future, historical and current fertility, mortality and immigration trends, the search for a new immigration policy, the impact of the baby boom generation on the population's age structure and the problems this creates, and recent shifts in population distribution and in the country's ethnic and linguistic makeup. The population policy proposals evolved thus far involve to a great extent the use of immigration as a lever for achieving given population objectives.

  19. Physiological factors influencing capillary growth.

    Egginton, S

    2011-07-01

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

  20. Method of Promoting Single Crystal Growth During Melt Growth of Semiconductors

    Su, Ching-Hua (Inventor)

    2013-01-01

    The method of the invention promotes single crystal growth during fabrication of melt growth semiconductors. A growth ampoule and its tip have a semiconductor source material placed therein. The growth ampoule is placed in a first thermal environment that raises the temperature of the semiconductor source material to its liquidus temperature. The growth ampoule is then transitioned to a second thermal environment that causes the semiconductor source material in the growth ampoule's tip to attain a temperature that is below the semiconductor source material's solidus temperature. The growth ampoule so-transitioned is then mechanically perturbed to induce single crystal growth at the growth ampoule's tip.

  1. Crossover from Nonequilibrium Fractal Growth to Equilibrium Compact Growth

    Sørensen, Erik Schwartz; Fogedby, Hans C.; Mouritsen, Ole G.

    1988-01-01

    Solidification controlled by vacancy diffusion is studied by Monte Carlo simulations of a two-dimensional Ising model defined by a Hamiltonian which models a thermally driven fluid-solid phase transition. The nonequilibrium morphology of the growing solid is studied as a function of time as the s...... as the system relaxes into equilibrium described by a temperature. At low temperatures the model exhibits fractal growth at early times and crossover to compact solidification as equilibrium is approached....

  2. Tax Evasion and Economic Growth in an Endogenous Growth Model

    加藤, 秀弥; KATO, Hideya

    2004-01-01

    This paper presents an endogenous growth model with tax evasion where government expenditures affect production. An individual evades a tax so as to maximize his or her utility, the tax authority controls the detection probability to maximize net tax revenue, and the government chooses the income tax rate to maximize individuals’ utility. The main conclusions are as follows. First, the optical income tax rate with tax evasion is higher than that without tax evasion. Second, the rise in a ...

  3. ELEMENTS OF THE NEOCLASSICAL GROWTH THEORY

    Florina Popa

    2014-12-01

    Full Text Available One of the relevant components of the contemporary economic science is the economic growth theory, the economic background of the time leading to new guidelines of the research. The neoclassical growth theory - the core of modern analysis - explains how the capital accumulation and technological changes affect the economy, significant for the analysis of the economic growth process being the Solow’s neoclassical growth model. The paper brief describes the elements of the economic growth model developed by Solow, both for the situation when it allows the explanation of extensive growth and that wherein the growth is of intensive nature, as a result of the intervention of exogenous technical progress – a determinant of factors productivity growth. It is highlighted the importance of the exogenous neoclassical model, proposed by Solow, who showed the determinant role of the technical progress in the economic growth phenomenon.

  4. Trajectories and models of individual growth

    Arseniy Karkach

    2006-11-01

    Full Text Available It has long been recognized that the patterns of growth play an important role in the evolution of age trajectories of fertility and mortality (Williams, 1957. Life history studies would benefit from a better understanding of strategies and mechanisms of growth, but still no comparative research on individual growth strategies has been conducted. Growth patterns and methods have been shaped by evolution and a great variety of them are observed. Two distinct patterns - determinate and indeterminate growth - are of a special interest for these studies since they present qualitatively different outcomes of evolution. We attempt to draw together studies covering growth in plant and animal species across a wide range of phyla focusing primarily on the noted qualitative features. We also review mathematical descriptions of growth, namely empirical growth curves and growth models, and discuss the directions of future research.

  5. Physiological roles revealed by ghrelin and ghrelin receptor deficient mice

    Ghrelin is a hormone made in the stomach and known primarily for its growth hormone releasing and orexigenic properties. Nevertheless, ghrelin through its receptor, the GHS-R1a, has been shown to exert many roles including regulation of glucose homeostasis, memory & learning, food addiction and neur...

  6. CHAPTER 1

    Dr Olaleye

    important gut-brain signal for appetite control and energy balance. ... induction of growth hormone release from the somatotroph cells of the anterior ... Copyright 2015 African Association of Physiological Sciences -ISSN: 2315-9987; e-ISSN: 2449-108X All rights reserved ..... Ghrelin administration on left ventricular function,.

  7. Somatostatin in the rat periventricular nucleus: sex differences and effect of gonadal steroids

    Vugt, van H.H.; Heijning, van de B.J.M.; Beek, van der E.M.

    2008-01-01

    In the rat, the sexual dimorphism in growth hormone release is driven by sex steroids, and is suggested to result mainly from differences in somatostatin (SOM) release patterns from the median eminence. We studied the effect of gonadal steroids on SOM peptide-containing cells in the periventricular

  8. The role of releasing hormones in the diagnosis of hypopituitarism ...

    Luteinising hormone-releasing factor and thyrotrophinreleasing factor were used in conjunction with the insulin tolerance test in 9 patients with known or suspected panhypopituitarism. It appears that growth hormone and luteinising hormone fail early in panhypopituitarism. Cortisol and thyroid-stimulating hormone ...

  9. Dynamics of anisotropic tissue growth

    Bittig, Thomas; Juelicher, Frank [Max Planck Institute for the Physics of Complex Systems, Noethnitzer Strasse 38, 01187 Dresden (Germany); Wartlick, Ortrud; Kicheva, Anna; Gonzalez-Gaitan, Marcos [Department of Biochemistry and Department of Molecular Biology, Geneva University, Sciences II, Quai Ernest-Ansermet 30, 1211 Geneva 4 (Switzerland)], E-mail: Marcos.Gonzalez@biochem.unige.ch, E-mail: julicher@pks.mpg.de

    2008-06-15

    We study the mechanics of tissue growth via cell division and cell death (apoptosis). The rearrangements of cells can on large scales and times be captured by a continuum theory which describes the tissue as an effective viscous material with active stresses generated by cell division. We study the effects of anisotropies of cell division on cell rearrangements and show that average cellular trajectories exhibit anisotropic scaling behaviors. If cell division and apoptosis balance, there is no net growth, but for anisotropic cell division the tissue undergoes spontaneous shear deformations. Our description is relevant for the study of developing tissues such as the imaginal disks of the fruit fly Drosophila melanogaster, which grow anisotropically.

  10. Environmental impact of population growth

    Naylor, Rosamond; Matson, Pamela

    Earth's population currently numbers 5.4 billion; even given optimistic assumptions for reduction in growth rates, the number will double by the middle of the next century with most of the increase in the developing countries. Rapid population growth in the developing world raises the fundamental dilemma of how to alleviate chronic hunger and poverty in the short run while preserving the atmosphere and ecosystem services required for long-term human and biospheric sustenance. This dilemma, and the compromises required to solve it, were discussed by twenty-five researchers from five countries at the Aspen Global Change Institute 1992 Summer Science Session III, Food, Conservation, and Global Environmental Change: Is Compromise Possible?, held from August 16 to 28, in Aspen, Colo.

  11. Inhomogeneous microstructural growth by irradiation

    Krishan, K.; Singh, Bachu Narain; Leffers, Torben

    1985-01-01

    In the present paper we discuss the development of heterogeneous microstructure for uniform irradiation conditions. It is shown that microstructural inhomogeneities on a scale of 0.1 μm can develop purely from kinematic considerations because of the basic structure of the rate equations used...... to describe such evolution. Two aspects of the growth of such inhomogeneities are discussed. Firstly, it is shown that a local variation in the sink densities of the various microstructural defects will tend to enhance the inhomogeneity rather than remove it. Secondly, such inhomogeneities will lead to point...... defect fluxes that result in a spatial growth of the inhomogeneous region, which will be stopped only when the microstructural density around this region becomes large. The results have important implications in the formation of denuded zones and void formation in metals....

  12. Maintaining flexibility pushes NYSEG's growth

    German, M.I.

    1997-01-01

    New York State Electric and Gas Corporation (NYSEG) recorded 1996 as one of its most successful years of natural gas expansion activity. In this landmark year, they opened their first storage facility, built more than 100 miles of new gas transmission and distribution pipelines, added nine new municipal franchises, and another 2+ Bcf of new gas load. The economy in NYSEG's service territory is not as robust as other LDCs enjoy elsewhere in the nation, yet they have created a significant momentum of growth that will continue through the end of the decade. It's due to the corporate strategy, which is straightforward in name and nature: Growth By Building On Our Unique Strengths. Their unique strengths dictate this strategy, which, in turn, demands that they focus intently on the performance of the core business. The paper discusses examples of how this strategy is being implemented

  13. Growth kinetics in multicomponent fluids

    Chen, S.; Lookman, T.

    1995-01-01

    The hydrodynamic effects on the late-stage kinetics in spinodal decomposition of multicomponent fluids are examined using a lattice Boltzmann scheme with stochastic fluctuations in the fluid and at the interface. In two dimensions, the three- and four-component immiscible fluid mixture (with a 1024 2 lattice) behaves like an off-critical binary fluid with an estimated domain growth of t 0.4 +/= 0.03 rather than t 1/3 as previously estimated, showing the significant influence of hydrodynamics. In three dimensions (with a 256 3 lattice), we estimate the growth as t 0.96 +/= 0.05 for both critical and off-critical quenches, in agreement with phenomenological theory

  14. Vascular Morphodynamics During Secondary Growth.

    de Reuille, Pierre Barbier; Ragni, Laura

    2017-01-01

    Quantification of vascular morphodynamics during secondary growth has been hampered by the scale of the process. Even in the tiny model plant Arabidopsis thaliana, the xylem can include more than 2000 cells in a single cross section, rendering manual counting impractical. Moreover, due to its deep location, xylem is an inaccessible tissue, limiting live imaging. A novel method to visualize and measure secondary growth progression has been proposed: "the Quantitative Histology" approach. This method is based on a detailed anatomical atlas, and image segmentation coupled with machine learning to automatically extract cell shapes and identify cell type. Here we present a new version of this approach, with a user-friendly interface implemented in the open source software LithoGraphX.

  15. Institutions, Entrepreneurship, and Economic Growth

    Bjørnskov, Christian; Foss, Nicolai Juul

    2016-01-01

    sample limitations, omitted variable biases, causality issues, and response heterogeneity. We argue that theories in management research, such as the resource-based view, transaction cost economics, and strategic entrepreneurship theory, can fill some of the conceptual and theoretical gaps.......We review the literature that links institutions, entrepreneurship, and economic growth outcomes, focusing in particular on empirical research. Most of the literature has an economics orientation, but we also review relevant literature from other social sciences, including management research...

  16. Population growth and economic development.

    Corbridge, S

    1989-01-01

    The Malthusian and neo-Malthusian approaches to the role of population growth in economic development and resource depletion are briefly outlined. Three arguments are then presented that emphasize demographic determinism, empirical evidence, and cause and effect. The author concludes that non-coercive family planning programs may have a role to play in countries that are unable to reduce inequalities, particularly for the poor and for women.

  17. Poverty, governance and economic growth

    Kefi Mohamed Karim

    2013-07-01

    Full Text Available The objective of this paper is to study the effect of governance and povrety on economic growth of a set of eight developing countries during the period 2000-2009, using a dynamic and static panel data model and a simultaneous equations model. The key findings generated from these three empirical tests stipulate a negative effect of governance on povrety and a positive effect of political instability and corruption on poverty

  18. Clean versus Dirty Economic Growth

    Palokangas, Tapio

    2012-01-01

    This document considers an economy with many regions and two engines of growth: horizontal R&D, which increases the number of polluting product lines; and vertical R&D, which improves productivity in these lines. Pollution in any region decreases welfare in all regions. Any group of regions can form a jurisdiction where a common policy maker controls pollution. Large jurisdictions, which can better internalize externality through pollution, perform vertical R&D. Because jurisdictions face dec...

  19. Reduced Deforestation and Economic Growth

    Patrick Doupe

    2014-01-01

    The clearing of forests for agricultural land and other marketable purposes is a well-trodden path of economic development. With these private benefits from deforestation come external costs: emissions from deforestation currently account for 12 per cent of global carbon emissions. A widespread intervention in reducing emissions from deforestation will affect the paths of agricultural expansion and economic growth of lower income nations. To investigate these processes, this paper presents a ...

  20. Green attitude and economic growth

    Ott, Ingrid; Soretz, Susanne

    2015-01-01

    We analyse the interdependence between green attitude and equilibrium development of environmental quality in an endogenous growth model. Individuals take only part of their impact on pollution into account, hence there is a negative externality of capital accumulation on environmental quality. Increasing wealth or increasing pollution enhance green attitude and reduce the externality, because individuals care more about the environment if their income is higher or if pollution is more obviou...