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Sample records for life cycle gonadotropin-releasing

  1. Antimüllerian hormone in gonadotropin releasing-hormone antagonist cycles

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    Arce, Joan-Carles; La Marca, Antonio; Mirner Klein, Bjarke

    2013-01-01

    To assess the relationships between serum antimüllerian hormone (AMH) and ovarian response and treatment outcomes in good-prognosis patients undergoing controlled ovarian stimulation using a gonadotropin-releasing hormone (GnRH) antagonist protocol.......To assess the relationships between serum antimüllerian hormone (AMH) and ovarian response and treatment outcomes in good-prognosis patients undergoing controlled ovarian stimulation using a gonadotropin-releasing hormone (GnRH) antagonist protocol....

  2. Neuroanatomical organization of gonadotropin-releasing hormone neurons during the oestrus cycle in the ewe

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    Malpaux Benoît

    2004-11-01

    Full Text Available Abstract Background During the preovulatory surge of gonadotropin-releasing hormone (GnRH, a very large amount of the peptide is released in the hypothalamo-hypophyseal portal blood for 24-36H00. To study whether this release is linked to a modification of the morphological organization of the GnRH-containing neurons, i.e. morphological plasticity, we conducted experiments in intact ewes at 4 different times of the oestrous cycle (before the expected LH surge, during the LH surge, and on day 8 and day 15 of the subsequent luteal phase. The cycle stage was verified by determination of progesterone and LH concentrations in the peripheral blood samples collected prior to euthanasia. Results The distribution of GnRH-containing neurons throughout the preoptic area around the vascular organ of the lamina terminalis was studied following visualisation using immunohistochemistry. No difference was observed in the staining intensity for GnRH between the different groups. Clusters of GnRH-containing neurons (defined as 2 or more neurons being observed in close contact were more numerous during the late follicular phase (43 ± 7 than during the luteal phase (25 ± 6, and the percentage of clusters was higher during the beginning of the follicular phase than during the luteal phase. There was no difference in the number of labelled neurons in each group. Conclusions These results indicate that the morphological organization of the GnRH-containing neurons in ewes is modified during the follicular phase. This transitory re-organization may contribute to the putative synchronization of these neurons during the surge. The molecular signal inducing this plasticity has not yet been identified, but oestradiol might play an important role, since in sheep it is the only signal which initiates the GnRH preovulatory surge.

  3. Premature luteinization during gonadotropin-releasing hormone antagonist cycles and its relationship with in vitro fertilization outcome.

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    Bosch, Ernesto; Valencia, Iván; Escudero, Ernesto; Crespo, Juana; Simón, Carlos; Remohí, José; Pellicer, Antonio

    2003-12-01

    To determine the prevalence and the effect of premature luteinization in GnRH antagonist IVF-ET cycles. Prospective observational study. In vitro fertilization-embryo transfer (IVF-ET) program at the Instituto Valenciano de Infertilidad. Eighty-one infertile patients undergoing controlled ovarian hyperstimulation with gonadotropins and GnRH antagonist for IVF-ET. Gonadotropin-releasing hormone (GnRH) antagonist was administered from stimulation day 6. Serum P, E(2), and LH were determined on the day of hCG administration. Cycles were grouped according to serum P level on the day of hCG administration ( or =1.2 ng/mL). Clinical pregnancy and implantation rates were determined. The incidence of premature luteinization was 38.3%. Total recombinant FSH dose and stimulation days differed significantly between the groups. Pregnancy rate (25.8% vs. 54.0%) and implantation rate (13.8% vs. 32.0%) were significantly lower in the premature luteinization group. Premature luteinization during GnRH antagonist IVF-ET cycles is a frequent event that is associated with lower pregnancy and implantation rates. Progesterone elevations are not related to serum LH levels and may reflect the mature granulosa cell response to high FSH exposure.

  4. Addition of gonadotropin releasing hormone agonist for luteal phase support in in-vitro fertilization: an analysis of 2739 cycles

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    Şimşek, Erhan; Kılıçdağ, Esra Bulgan; Aytaç, Pınar Çağlar; Çoban, Gonca; Şimşek, Seda Yüksel; Çok, Tayfun; Haydardedeoğlu, Bülent

    2015-01-01

    Objective Luteal phase is defective in in vitro fertilization (IVF) cycles, and many regimens were tried for the very best luteal phase support (LPS). Gonadotropin releasing hormone (GnRH) agonist use, which was administered as an adjunct to the luteal phase support in IVF cycles, was suggested to improve pregnancy outcome measures in certain randomized studies. We analyzed the effects of addition of GnRH agonist to standard progesterone luteal support on pregnancy outcome measures, particularly the live birth rates. Material and Methods This is a retrospective cohort study, including 2739 IVF cycles. Long GnRH agonist and antagonist stimulation IVF cycles with cleavage-stage embryo transfer were included. Cycles were divided into two groups: Group A included cycles with single-dose GnRH agonist plus progesterone LPS and Group B included progesterone only LPS. Live birth rates were the primary outcome measures of the analysis. Miscarriage rates and multiple pregnancy rates were the secondary outcome measures. Results Live birth rates were not statistically different in GnRH agonist plus progesterone (Group A) and progesterone only (Group B) groups in both the long agonist and antagonist stimulation arms (40.8%/41.2% and 32.8%/34.4%, p<0.05 respectively). Moreover, pregnancy rates, implantation rates, and miscarriage rates were found to be similar between groups. Multiple pregnancy rates in antagonist cycles were significantly higher in Group A than those in Group B (12.0% and 6.9%, respectively). Conclusion A beneficial effect of a single dose of GnRH agonist administration as a luteal phase supporting agent is yet to be determined because of the wide heterogeneity of data present in literature. Well-designed randomized clinical studies are required to clarify any effect of luteal GnRH agonist addition on pregnancy outcome measures with different doses, timing, and administration routes of GnRH agonists. PMID:26097392

  5. Impact of gonadotropin-releasing hormone antagonist addition on pregnancy rates in gonadotropin-stimulated intrauterine insemination cycles

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    Shikha Jain

    2016-01-01

    Full Text Available OBJECTIVES: The objective of the study is to evaluate the efficacy of gonadotropin-releasing hormone (GnRH antagonist in improving clinical pregnancy rate in gonadotropin-stimulated intrauterine insemination (IUI cycles in patients of unexplained infertility. STUDY DESIGN: This was a prospective, randomized case-controlled study. SETTINGS: The study was conducted in the infertility clinic of a tertiary care center. MATERIALS AND METHODS: Four hundred twenty-seven women undergoing IUI following controlled ovarian stimulation with gonadotropins (recombinant follicle-stimulating hormone [r-FSH] 75 IU/day were randomly divided into two groups. Women in Group I received GnRH antagonist (Cetrorelix 0.25 mg/day in a multiple dose flexible protocol. Women in Group II received r-FSH alone. Ovulatory trigger was given with human chorionic gonadotropin 5000 IU when dominant follicle was ≥18 mm. IUI was performed within 44-48 h. Both groups received similar luteal phase support. Primary outcome measure was clinical pregnancy rate. The trial was powered to detect an absolute increase in clinical pregnancy rate by 13% from an assumed 20% clinical pregnancy rate in the control group, with an alpha error level of 0.05 and a beta error level of 0.20. RESULTS: Clinical pregnancy rate in Groups I and II was 27.6% (n = 56 and 26.5% (n = 54, respectively (P=0.800. Ongoing pregnancy and multiple pregnancy rates were likewise similar between the groups. CONCLUSIONS: Addition of GnRH antagonist to gonadotropin-stimulated IUI cycles results in no significant difference in clinical pregnancy rate.

  6. Pregnancy rate in women with adenomyosis undergoing fresh or frozen embryo transfer cycles following gonadotropin-releasing hormone agonist treatment.

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    Park, Chan Woo; Choi, Min Hye; Yang, Kwang Moon; Song, In Ok

    2016-09-01

    To determine the preferred regimen for women with adenomyosis undergoing in vitro fertilization (IVF), we compared the IVF outcomes of fresh embryo transfer (ET) cycles with or without gonadotropin-releasing hormone (GnRH) agonist pretreatment and of frozen-thawed embryo transfer (FET) cycles following GnRH agonist treatment. This retrospective study included 241 IVF cycles of women with adenomyosis from January 2006 to January 2012. Fresh ET cycles without (147 cycles, group A) or with (105 cycles, group B) GnRH agonist pretreatment, and FET cycles following GnRH agonist treatment (43 cycles, group C) were compared. Adenomyosis was identified by using transvaginal ultrasound at the initial workup and classified into focal and diffuse types. The IVF outcomes were also subanalyzed according to the adenomyotic region. GnRH agonist pretreatment increased the stimulation duration (11.5±2.1 days vs. 9.9±2.0 days) and total dose of gonadotropin (3,421±1,141 IU vs. 2,588±1,192 IU), which resulted in a significantly higher number of retrieved oocytes (10.0±8.2 vs. 7.9±6.8, p=0.013) in group B than in group A. Controlled ovarian stimulation for freezing resulted in a significantly higher number of retrieved oocytes (14.3±9.2 vs. 10.0±8.2, p=0.022) with a lower dose of gonadotropin (2,974±1,112 IU vs. 3,421±1,141 IU, p=0.037) in group C than in group B. The clinical pregnancy rate in group C (39.5%) tended to be higher than those in groups B (30.5%) and A (25.2%) but without a significant difference. FET following GnRH agonist pretreatment tended to increase the pregnancy rate in patients with adenomyosis. Further large-scale prospective studies are required to confirm this result.

  7. Does the use of gonadotropin-releasing hormone antagonists in natural IVF cycles for poor responder patients cause more harm than benefit?

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    Aksoy, Senai; Yakin, Kayhan; Seyhan, Ayse; Oktem, Ozgur; Alatas, Cengiz; Ata, Baris; Urman, Bulent

    2016-06-01

    Poor ovarian response to controlled ovarian stimulation (COS) is one of the most critical factors that substantially limits the success of assisted reproduction techniques (ARTs). Natural and modified natural cycle IVF are two options that could be considered as a last resort. Blocking gonadotropin-releasing hormone (GnRH) actions in the endometrium via GnRH receptor antagonism may have a negative impact on endometrial receptivity. We analysed IVF outcomes in 142 natural (n = 30) or modified natural (n = 112) IVF cycles performed in 82 women retrospectively. A significantly lower proportion of natural cycles reached follicular aspiration compared to modified natural cycles (56.7% vs. 85.7%, p numbers of IVF cycles ending in embryo transfer (26.7% vs. 44.6%) was not statistically significant between natural cycle and modified natural IVF cycles. Clinical pregnancy (6.7% vs. 7.1%) and live birth rates per initiated cycle (6.7% vs. 5.4%) were similar between the two groups. Notably, the implantation rate was slightly lower in modified natural cycles (16% vs. 25%, p > 0.05). There was a trend towards higher clinical pregnancy (25% vs. 16%) and live birth (25% vs. 12%) rates per embryo transfer in natural cycles compared to modified natural cycles, but the differences did not reach statistical significance.

  8. New trends in combined use of gonadotropin-releasing hormone antagonists with gonadotropins or pulsatile gonadotropin-releasing hormone in ovulation induction and assisted reproductive technologies.

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    Gordon, K; Danforth, D R; Williams, R F; Hodgen, G D

    1992-10-01

    The use of gonadotropin-releasing hormone agonists as adjunctive therapy with gonadotropins for ovulation induction in in vitro fertilization and other assisted reproductive technologies has become common clinical practice. With the recent advent of potent gonadotropin-releasing hormone antagonists free from the marked histamine-release effects that stymied earlier compounds, an attractive alternative method may be available. We have established the feasibility of combining gonadotropin-releasing hormone antagonist-induced inhibition of endogenous gonadotropins with exogenous gonadotropin therapy for ovulation induction in a nonhuman primate model. Here, the principal benefits to be gained from using the gonadotropin-releasing hormone antagonist rather than the gonadotropin-releasing hormone agonist are the immediate inhibition of pituitary gonadotropin secretion without the "flare effect," which brings greater safety and convenience for patients and the medical team and saves time and money. We have also recently demonstrated the feasibility of combining gonadotropin-releasing hormone antagonist with pulsatile gonadotropin-releasing hormone therapy for the controlled restoration of gonadotropin secretion and gonadal steroidogenesis culminating in apparently normal (singleton) ovulatory cycles. This is feasible only with gonadotropin-releasing hormone antagonists because, unlike gonadotropin-releasing hormone agonists, they achieve control of the pituitary-ovarian axis without down regulation of the gonadotropin-releasing hormone receptor system. This capacity to override gonadotropin-releasing hormone antagonist-induced suppression of pituitary-ovarian function may allow new treatment modalities to be employed for women who suffer from chronic hyperandrogenemia with polycystic ovarian disease.

  9. PROGESTERONE/ESTRADIOL RATIO IN THE LATE FOLLICULAR PHASE OF LONG GONADOTROPIN-RELEASING HORMONE AGONIST CYCLES DID NOT DIFFER BETWEEN CONCEIVED AND NOT-CONCEIVED WOMEN

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    L. Safdarian

    2008-04-01

    Full Text Available There is a challenging debate on the effect of premature luteinization on the clinical outcome of ‘controlled ovarian hyperstimulation' (COH using long ‘gonadotropin-releasing hormone agonist' (GnRHa cycles. Premature luteinization is defined as late follicular progesterone/estradiol ratio more than 1 on the day of human chorionic gonadotropin (HCG administration. We carried out a retrospective case-control study on 75 conceived cases versus 75 not-conceived control women, receiving long GnRHa cycles in their first cycle of treatment. Premature luteinization developed in 15% of the case group vs. 22% of the control group. Neither the late follicular progesterone/estradiol (P/E2 ratio was significantly different between the two groups, nor the day 3 follicle stimulating hormone (FSH, serum estradiol level on the HCG day, total amount of human menopausal gonadotropins ampoules, number of follicles, retrieved oocytes and transferred embryos. Endometrial thickness was significantly more in the pregnant women than in the non-pregnant group. Premature luteinization seems not to adversely affect the clinical outcome of COH.

  10. Gonadotropin-releasing hormone agonist triggering is effective, even at a low dose, for final oocyte maturation in ART cycles: Case series.

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    Gülekli, Bülent; Göde, Funda; Sertkaya, Zerrin; Işık, Ahmet Zeki

    2015-01-01

    To investigate the efficacy of low-dose gonadotropin-releasing hormone (GnRH) agonist for final oocyte maturation in females undergoing assisted reproductive treatment (ART) cycles. Nine females undergoing ovarian stimulation in a GnRH antagonist protocol who received triptorelin 0.1 mg to trigger final oocyte maturation were included. Treatment outcomes of these patients were compared with those of controls, matched for age and oocyte number (n=14), who received 0.2 mg triptorelin at the same time. The luteal phase was supported with vaginal micronized progesterone and oral estradiol hemihydrate 2 mg twice daily. The mean (±) numbers of retrieved, metaphase II, and fertilized oocytes were 15.66±7.82, 14±7.28, and 10.11±5.86, respectively. The implantation and clinical pregnancy rates were 46.1% and 71.4%, respectively. Of the pregnancies, 2 were live births, 1 was a preterm birth (twins), 2 are on-going, and 2 ended as miscarriages. No case of OHSS was encountered. On comparison of the results of these patients (fresh cycles; n=7) with those of matched controls, there were no significant differences in terms of retrieved mature oocytes, implantation rates, or clinical pregnancy rates (p>0.05). These findings suggest that low-dose GnRH agonist triggering has similar efficacy as standard doses in terms of retrieved mature oocytes and clinical pregnancy rates in in vitro fertilization cycles.

  11. Comparison of gonadotropin-releasing hormone agonist with GnRH antagonist in polycystic ovary syndrome patients undergoing in vitro fertilization cycle: Retrospective analysis from a tertiary center and review of literature

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    Neeta Singh

    2014-01-01

    Full Text Available Introduction: Polycystic ovary syndrome (PCOS is one of the most common infertility factor for which women are enrolled in in vitro fertilization (IVF technique. In the recent years, gonadotropin releasing hormone antagonist protocol has emerged as the protocol of choice for controlled ovarian hyperstimulation in these patients. Objectives: The objective of the present study is to compare conventional long agonist protocol with fixed antagonist protocol in PCOS patients undergoing IVF cycle. Materials and Methods: Retrospective analysis of 4 years data of a single center from northern India. Totally 81 patients who had long agonist protocol were compared with 36 patients with similar baseline characteristics who had antagonist protocol. Result: Total dose of gonadotropin required was significantly lower (P - 0.004 in the antagonist group. There was no significant difference in pregnancy rate or incidence of ovarian hyperstimulation syndrome between two groups. Cycle cancellation due to arrest of follicular growth was significantly higher in the antagonist group (P - 0.027. Conclusion: More randomized control trials and meta-analysis are required before replacing conventional long agonist protocol with antagonist protocol in patients with polycystic ovary syndrome.

  12. Gonadotropin releasing hormone agonists: Expanding vistas

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    Navneet Magon

    2011-01-01

    Full Text Available Gonadotropin-releasing hormone (GnRH agonists are derived from native GnRH by amino acid substitution which yields the agonist resistant to degradation and increases its half-life. The hypogonadotropic hypogonadal state produced by GnRH agonists has been often dubbed as "pseudomenopause" or "medical oophorectomy," which are both misnomers. GnRH analogues (GnRH-a work by temporarily "switching off" the ovaries. Ovaries can be "switched off" for the therapy and therapeutic trial of many conditions which include but are not limited to subfertility, endometriosis, adenomyosis, uterine leiomyomas, precocious puberty, premenstrual dysphoric disorder, chronic pelvic pain, or the prevention of menstrual bleeding in special clinical situations. Rapidly expanding vistas of usage of GnRH agonists encompass use in sex reassignment of male to female transsexuals, management of final height in cases of congenital adrenal hyperplasia, and preserving ovarian function in women undergoing cytotoxic chemotherapy. Hypogonadic side effects caused by the use of GnRH agonists can be tackled with use of "add-back" therapy. Goserelin, leuprolide, and nafarelin are commonly used in clinical practice. GnRH-a have provided us a powerful therapeutic approach to the treatment of numerous conditions in reproductive medicine. Recent synthesis of GnRH antagonists with a better tolerability profile may open new avenues for both research and clinical applications. All stakeholders who are partners in women′s healthcare need to join hands to spread awareness so that these drugs can be used to realize their full potential.

  13. Dual trigger with combination of gonadotropin-releasing hormone agonist and human chorionic gonadotropin significantly improves the live-birth rate for normal responders in GnRH-antagonist cycles.

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    Lin, Ming-Huei; Wu, Frank Shao-Ying; Lee, Robert Kuo-Kuang; Li, Sheng-Hsiang; Lin, Shyr-Yeu; Hwu, Yuh-Ming

    2013-11-01

    To investigate whether dual triggering of final oocyte maturation with a combination of gonadotropin-releasing hormone (GnRH) agonist and human chorionic gonadotropin (hCG) can improve the live-birth rate for normal responders in GnRH-antagonist in vitro fertilization/intracytoplasmic sperm injection (IVF-ICSI) cycles. Retrospective cohort study. Infertility unit of a university-affiliated medical center. Normal responders to controlled ovarian hyperstimulation who were undergoing IVF-ICSI with a GnRH antagonist protocol. Standard dosage of hCG trigger (6,500 IU of recombinant hCG) versus dual trigger (0.2 mg of triptorelin and 6,500 IU of recombinant hCG). Live-birth, clinical pregnancy, and implantation rates per cycle. A total of 376 patients with 378 completed cycles with embryo transfer were enrolled (hCG trigger/control group: n = 187; dual trigger/study group: n = 191). The dual trigger group demonstrated statistically significantly higher implantation (29.6% vs. 18.4%), clinical pregnancy (50.7% vs. 40.1%), and live-birth (41.3% vs. 30.4%) rates as compared with the hCG trigger group. There was no statistically significant difference in terms of patient demographics, cycle parameters, or embryo quality. Dual trigger of final oocyte maturation with a GnRH-agonist and a standard dosage of hCG in normal responders statistically significantly improves implantation, clinical pregnancy, and live-birth rates in GnRH-antagonist IVF cycles. Copyright © 2013 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  14. Short versus Long Gonadotropin-Releasing Hormone Analogue Suppression Protocols in IVF/ICSI Cycles in Patients of Various Age Ranges.

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    Jianping Ou

    Full Text Available To compare the two GnRH-a protocols (long GnRH-a protocol and short GnRH-a protocol for ovarian stimulation in IVF/ICSI cycles in patients of various age ranges.A total of 5662 IVF-ET/ICSI cycles from 2010 to 2013 were retrospectively identified. The cycles were divided into two groups: a long protocol group and short protocol group. In each group, the patients were divided into four age ranges: 40 years. The duration of stimulation, total dose of Gn, implantation rate and pregnancy rate were compared.The total dose of Gn was significantly higher, and the duration of stimulation was significantly longer, in the long protocol group than in the short protocol group for all age ranges (P<0.05. If the patients were of the same age range, the number of oocytes retrieved, MII oocytes, and high-quality embryos in the long protocol group were all significantly greater than those in the short protocol group (P<0.05. In the long protocol group, the clinical pregnancy rates of the four age ranges were 52.76%, 44.33%, 36.15% and 13.33%, respectively, which were significantly higher than those in the short protocol group (33.33%, 24.58%, 22.49% and 8.72%, respectively; P<0.05. The same trend was also found in the implantation rates of the four age ranges. As the age increased, the clinical pregnancy and implantation rates, as well as the number of oocytes retrieved, MII oocytes, and high-quality embryos, of the long protocol group significantly decreased (P<0.05.Our study demonstrated that regardless of patient age, the long protocol was superior to the short protocol in terms of the number of retrieved oocytes, as well as the implantation and pregnancy rates.

  15. A high response to controlled ovarian stimulation induces premature luteinization with a negative impact on pregnancy outcomes in a gonadotropin-releasing hormone antagonist cycle.

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    Koo, Hwa Seon; Cha, Sun Hwa; Kim, Hye Ok; Song, In Ok; Min, Eung Gi; Yang, Kwang Moon; Park, Chan Woo

    2015-12-01

    The goal of this study was to investigate the relationship between serum progesterone (P4) levels on the day of human chorionic gonadotropin (hCG) administration and the pregnancy rate among women undergoing controlled ovarian stimulation for in vitro fertilization (IVF) or intracytoplasmic sperm injection-embryo transfer (ICSI-ET) using a flexible antagonist protocol. This prospective study included 200 IVF and ICSI-ET cycles in which a flexible antagonist protocol was used. The patients were divided into five distinct groups according to their serum P4 levels at the time of hCG administration (0.80, 0.85, 0.90, 0.95, and 1.00 ng/mL). The clinical pregnancy rate (CPR) was calculated for each P4 interval. Statistically significant differences were observed at a serum P4 level of 0.9 ng/mL. These data suggest that a serum P4 concentration of 0.9 ng/mL may represent the optimal threshold level for defining premature luteinization (PL) based on the presence of a significant negative impact on the CPR. The CPR for each round of ET was significantly lower in the PL group defined using this threshold (25.8% vs. 41.8%; p=0.019), and the number of oocytes retrieved was significantly higher than in the non-PL group (17.3±7.2 vs. 11.0±7.2; p=0.001). Elevated serum P4 levels on the day of hCG administration were associated with a reduced CPR, despite the retrieval of many oocytes. Measuring serum P4 values at the time of hCG administration is necessary in order to determine the optimal strategy for embryo transfer.

  16. Ghrelin decreases firing activity of gonadotropin-releasing hormone (GnRH neurons in an estrous cycle and endocannabinoid signaling dependent manner.

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    Imre Farkas

    Full Text Available The orexigenic peptide, ghrelin is known to influence function of GnRH neurons, however, the direct effects of the hormone upon these neurons have not been explored, yet. The present study was undertaken to reveal expression of growth hormone secretagogue receptor (GHS-R in GnRH neurons and elucidate the mechanisms of ghrelin actions upon them. Ca(2+-imaging revealed a ghrelin-triggered increase of the Ca(2+-content in GT1-7 neurons kept in a steroid-free medium, which was abolished by GHS-R-antagonist JMV2959 (10 µM suggesting direct action of ghrelin. Estradiol (1nM eliminated the ghrelin-evoked rise of Ca(2+-content, indicating the estradiol dependency of the process. Expression of GHS-R mRNA was then confirmed in GnRH-GFP neurons of transgenic mice by single cell RT-PCR. Firing rate and burst frequency of GnRH-GFP neurons were lower in metestrous than proestrous mice. Ghrelin (40 nM-4 μM administration resulted in a decreased firing rate and burst frequency of GnRH neurons in metestrous, but not in proestrous mice. Ghrelin also decreased the firing rate of GnRH neurons in males. The ghrelin-evoked alterations of the firing parameters were prevented by JMV2959, supporting the receptor-specific actions of ghrelin on GnRH neurons. In metestrous mice, ghrelin decreased the frequency of GABAergic mPSCs in GnRH neurons. Effects of ghrelin were abolished by the cannabinoid receptor type-1 (CB1 antagonist AM251 (1µM and the intracellularly applied DAG-lipase inhibitor THL (10 µM, indicating the involvement of retrograde endocannabinoid signaling. These findings demonstrate that ghrelin exerts direct regulatory effects on GnRH neurons via GHS-R, and modulates the firing of GnRH neurons in an ovarian-cycle and endocannabinoid dependent manner.

  17. Non-invasive assessment of the reproductive cycle in free-ranging female African elephants (Loxodonta africana treated with a gonadotropin-releasing hormone (GnRH vaccine for inducing anoestrus

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    Benavides Valades Gabriela

    2012-08-01

    Full Text Available Abstract Background In southern Africa, various options to manage elephant populations are being considered. Immunocontraception is considered to be the most ethically acceptable and logistically feasible method for control of smaller and confined populations. In this regard, the use of gonadotropin-releasing hormone (GnRH vaccine has not been investigated in female elephants, although it has been reported to be safe and effective in several domestic and wildlife species. The aims of this study were to monitor the oestrous cycles of free-ranging African elephant cows using faecal progestagen metabolites and to evaluate the efficacy of a GnRH vaccine to induce anoestrus in treated cows. Methods Between May 2009 - June 2010, luteal activity of 12 elephant cows was monitored non-invasively using an enzyme immunoassay detecting faecal 5alpha-reduced pregnanes (faecal progestagen metabolites, FPM on a private game reserve in South Africa. No bulls of breeding age were present on the reserve prior to and for the duration of the study. After a 3-month control period, 8 randomly-selected females were treated twice with 600 micrograms of GnRH vaccine (Improvac®, Pfizer Animal Health, Sandton, South Africa 5-7 weeks apart. Four of these females had been treated previously with the porcine zona pellucida (pZP vaccine for four years (2004-2007. Results All 12 monitored females (8 treated and 4 controls showed signs of luteal activity as evidenced by FPM concentrations exceeding individual baseline values more than once. A total of 16 oestrous cycles could be identified in 8 cows with four of these within the 13 to 17 weeks range previously reported for captive African elephants. According to the FPM concentrations the GnRH vaccine was unable to induce anoestrus in the treated cows. Overall FPM levels in samples collected during the wet season (mean 4.03 micrograms/gram dry faeces were significantly higher (P Conclusions The GnRH vaccination protocol failed

  18. Gonadotropin-releasing hormone in the ovary.

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    Metallinou, Chryssa; Asimakopoulos, Byron; Schröer, Andreas; Nikolettos, Nikos

    2007-12-01

    Gonadotropin-releasing hormone (GnRH) plays a pivotal role in the physiology of reproduction in mammals. GnRH acts by binding to the GnRH receptor (GnRHR). In humans, only 1 conventional GnRH receptor subtype (type I GnRH receptor) has been found. In the human genome, 2 forms of GnRH have been identified, GnRH-I (mammal GnRH) and GnRH-II (chicken GnRH II). Both forms and their common receptor are expressed, apart from the hypothalamus, in various compartments of the human ovary. Gonadal steroids, gonadotropins, and GnRH itself controls the regulation of the GnRH/GnRHR system gene expression in the human ovary. The 2 types of GnRH acting paracrinally/autocrinally influence ovarian steroidogenesis, decrease the proliferation, and induce apoptosis of ovarian cells. In this review, the biology of GnRH/GnRHR system in humans, the potential roles of GnRH, and the direct effects of GnRH analogues in ovarian cells are discussed.

  19. Basic understanding of gonadotropin-releasing hormone-agonist triggering.

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    Casper, Robert F

    2015-04-01

    A single bolus of human chorionic gonadotropin (hCG) at midcycle has been the gold standard for triggering final oocyte maturation and ovulation in assisted reproductive technology cycles. More recently, gonadotropin-releasing hormone (GnRH)-agonist (GnRH-a) triggering has been introduced. The GnRH-a trigger may allow a more physiologic surge of both luteinizing hormone (LH) and follicle-stimulating hormone, although whether the combined surge will result in improved oocyte and embryo quality remains to be seen. However, the short duration of the LH surge with the GnRH-a trigger (approximately 34 hours) has been shown to be beneficial for preventing ovarian hyperstimulation syndrome in GnRH antagonist in vitro fertilization (IVF) cycles when compared with the prolonged elevation of hCG (≥6 days) after exposure to an hCG bolus. This review discusses the physiologic basis for the use of a GnRH-a trigger in IVF cycles.

  20. Gonadotropin-releasing hormone agonist-induced pituitary apoplexy

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    Fergus Keane

    2016-06-01

    Full Text Available Pituitary apoplexy represents an uncommon endocrine emergency with potentially life-threatening consequences. Drug-induced pituitary apoplexy is a rare but important consideration when evaluating patients with this presentation. We describe an unusual case of a patient with a known pituitary macroadenoma presenting with acute-onset third nerve palsy and headache secondary to tumour enlargement and apoplexy. This followed gonadotropin-releasing hormone (GNRH agonist therapy used to treat metastatic prostate carcinoma. Following acute management, the patient underwent transphenoidal debulking of his pituitary gland with resolution of his third nerve palsy. Subsequent retrospective data interpretation revealed that this had been a secretory gonadotropinoma and GNRH agonist therapy resulted in raised gonadotropins and testosterone. Hence, further management of his prostate carcinoma required GNRH antagonist therapy and external beam radiotherapy. This case demonstrates an uncommon complication of GNRH agonist therapy in the setting of a pituitary macroadenoma. It also highlights the importance of careful, serial data interpretation in patients with pituitary adenomas. Finally, this case presents a unique insight into the challenges of managing a hormonal-dependent prostate cancer in a patient with a secretory pituitary tumour.

  1. Development of gonadotropin-releasing hormone secretion and pituitary response.

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    Glanowska, Katarzyna M; Burger, Laura L; Moenter, Suzanne M

    2014-11-05

    Acquisition of a mature pattern of gonadotropin-releasing hormone (GnRH) secretion from the CNS is a hallmark of the pubertal process. Little is known about GnRH release during sexual maturation, but it is assumed to be minimal before later stages of puberty. We studied spontaneous GnRH secretion in brain slices from male mice during perinatal and postnatal development using fast-scan cyclic voltammetry (FSCV) to detect directly the oxidation of secreted GnRH. There was good correspondence between the frequency of GnRH release detected by FSCV in the median eminence of slices from adults with previous reports of in vivo luteinizing hormone (LH) pulse frequency. The frequency of GnRH release in the late embryonic stage was surprisingly high, reaching a maximum in newborns and remaining elevated in 1-week-old animals despite low LH levels. Early high-frequency GnRH release was similar in wild-type and kisspeptin knock-out mice indicating that this release is independent of kisspeptin-mediated excitation. In vivo treatment with testosterone or in vitro treatment with gonadotropin-inhibitory hormone (GnIH) reduced GnRH release frequency in slices from 1-week-old mice. RF9, a putative GnIH antagonist, restored GnRH release in slices from testosterone-treated mice, suggesting that testosterone inhibition may be GnIH-dependent. At 2-3 weeks, GnRH release is suppressed before attaining adult patterns. Reduction in early life spontaneous GnRH release frequency coincides with the onset of the ability of exogenous GnRH to induce pituitary LH secretion. These findings suggest that lack of pituitary secretory response, not lack of GnRH release, initially blocks downstream activation of the reproductive system.

  2. Regulation of tonic gonadotropin release in prepubertal female hamsters

    Energy Technology Data Exchange (ETDEWEB)

    Smith, S.G.; Matt, K.S.; Prestowitz, W.F.; Stetson, M.H.

    1982-04-01

    Basal serum gonadotropin levels were monitored weekly in female hamsters from birth to 10 weeks of age. Hamsters raised on three different photoperiods presented uniform pre- and postpubertal patterns of serum LH and FSH, suggesting that gonadotropin release in the young hamster occurs independently of ambient photoperiod. In all groups, serum LH levels increased gradually in animals up to 4 weeks of age, after which levels plateaued at 50--100 ng/ml. Serum FSH was markedly elevated in 2- and 3-week-old hamsters (800--1200 ng/ml), but remained at 200--400 ng/ml in all other groups. We next examined the change in the responsiveness of the pituitary to exogenous gonadotropin-releasing hormone (GnRH) challenge. Female hamsters 2 days of age failed to respond to any dose (0.025--1000 ng) of GnRH, while 10-day old females responded in typical dose-dependent fashion. GnRH-stimulated LH release first occurred in 6-day-old hamsters and was maximal by day 9, whereas FSH release first occurred on day 8 and was maximal by day 9. The prepubertal pattern of gonadotropin release can, in part, be explained on the basis of the development of pituitary GnRH sensitivity, which occurs independently of photoperiod.

  3. Kisspeptin regulates gonadotropin-releasing hormone secretion in gonadotropin-releasing hormone/enhanced green fluorescent protein transgenic rats

    Institute of Scientific and Technical Information of China (English)

    Haogang Xue; Chunying Yang; Xiaodong Ge; Weiqi Sun; Chun Li; Mingyu Qi

    2013-01-01

    Kisspeptin is essential for activation of the hypothalamo-pituitary-gonadal axis. In this study, we established gonadotropin-releasing hormone/enhanced green fluorescent protein transgenic rats. Rats were injected with 1, 10, or 100 pM kisspeptin-10, a peptide derived from full-length kisspeptin, into the arcuate nucleus and medial preoptic area, and with the kisspeptin antagonist peptide 234 into the lateral cerebral ventricle. The results of immunohistochemical staining revealed that pulsatile luteinizing hormone secretion was suppressed after injection of antagonist peptide 234 into the lateral cerebral ventricle, and a significant increase in luteinizing hormone level was observed after kisspeptin-10 injection into the arcuate nucleus and medial preoptic area. The results of an enzyme-linked immunosorbent assay showed that luteinizing hormone levels during the first hour of kisspeptin-10 infusion into the arcuate nucleus were significantly greater in the 100 pM kisspeptin-10 group than in the 10 pM kisspeptin-10 group. These findings indicate that kisspeptin directly promotes gonadotropin-releasing hormone secretion and luteinizing hormone release in gonadotropin-releasing hormone/enhanced green fluorescent protein transgenic rats. The arcuate nucleus is a key component of the kisspeptin-G protein-coupled receptor 54 signaling pathway underlying regulating luteinizing hormone pulse secretion.

  4. Efficacy and safety of gonadotropin-releasing hormone agonists used in the treatment of prostate cancer

    Directory of Open Access Journals (Sweden)

    Choi S

    2011-12-01

    Full Text Available Seungtaek Choi, Andrew K LeeDepartment of Radiation Oncology, MD Anderson Cancer Center, Houston, TX, USAAbstract: Androgen deprivation therapy (ADT is the most effective systemic treatment for prostate cancer. ADT has been shown to have a high rate of response and to improve overall survival in patients with metastatic prostate cancer. In addition, multiple studies have shown that adding ADT to external beam radiation therapy leads to improvement in cure rates and overall survival in prostate cancer patients. The most commonly used ADT is gonadotropin-releasing hormone (GnRH agonist therapy. Although GnRH agonist therapy has significant benefits for patients with prostate cancer, it has also been shown to have significant side effects, including fatigue, hot flashes, decreased libido, decreased quality of life, obesity, diabetes mellitus, coronary artery disease, decreased bone mineral density, and increased risk of fractures. Therefore, it is crucial that the benefits of ADT be weighed against its potential adverse effects before its use.Keywords: androgen deprivation therapy, gonadotropin-releasing hormone agonists, prostate cancer

  5. Dual trigger with combination of gonadotropin-releasing hormone agonist and human chorionic gonadotropin significantly improves the live-birth rate for normal responders in GnRH-antagonist cycles

    National Research Council Canada - National Science Library

    Lin, Ming-Huei; Wu, Frank Shao-Ying; Lee, Robert Kuo-Kuang; Li, Sheng-Hsiang; Lin, Shyr-Yeu; Hwu, Yuh-Ming

    2013-01-01

    ...) agonist and human chorionic gonadotropin (hCG) can improve the live-birth rate for normal responders in GnRH-antagonist in vitro fertilization/intracytoplasmic sperm injection (IVF-ICSI) cycles...

  6. Estradiol potentiation of gonadotropin-releasing hormone responsiveness in the anterior pituitary is mediated by an increase in gonadotropin-releasing hormone receptors

    Energy Technology Data Exchange (ETDEWEB)

    Menon, M.; Peegel, H.; Katta, V.

    1985-02-15

    In order to investigate the mechanism by which 17 beta-estradiol potentiates the action of gonadotropin-releasing hormone on the anterior pituitary in vitro, cultured pituitary cells from immature female rats were used as the model system. Cultures exposed to estradiol at concentrations ranging from 10(-10) to 10(-6) mol/L exhibited a significant augmentation of luteinizing hormone release in response to a 4-hour gonadotropin-releasing hormone (10 mumol/L) challenge at a dose of 10(-9) mol/L compared to that of control cultures. The estradiol augmentation of luteinizing hormone release was also dependent on the duration of estradiol exposure. When these cultures were incubated with tritium-labeled L-leucine, an increase in incorporation of radiolabeled amino acid into total proteins greater than that in controls was observed. A parallel stimulatory effect of estradiol on iodine 125-labeled D-Ala6 gonadotropin-releasing hormone binding was observed. Cultures incubated with estradiol at different concentrations and various lengths of time showed a significant increase in gonadotropin-releasing hormone binding capacity and this increase was abrogated by cycloheximide. Analysis of the binding data showed that the increase in gonadotropin-releasing hormone binding activity was due to a change in the number of gonadotropin-releasing hormone binding sites rather than a change in the affinity. These results suggest that (1) estradiol treatment increases the number of pituitary receptors for gonadotropin-releasing hormone, (2) the augmentary effect of estradiol on luteinizing hormone release at the pituitary level might be mediated, at least in part, by the increase in the number of binding sites of gonadotropin-releasing hormone, and (3) new protein synthesis may be involved in estradiol-mediated gonadotropin-releasing hormone receptor induction.

  7. Spontaneous ovulation in in vitro fertilization-embryo transfer cycles using gonadotropin-releasing hormone antagonist:a large-sample retrospective study%GnRH拮抗剂方案在体外受精-胚胎移植周期中自发排卵风险的大样本量回顾性研究

    Institute of Scientific and Technical Information of China (English)

    罗璐; 陈明晖; 贾梦希; 王琼; 周灿权

    2016-01-01

    Objective To investigate the premature spontaneous ovulation rates in in vitro fertilization-embryo transfer (IVF-ET) cycles using gonadotropin-releasing hormone antagonist (GnRH-ant) and gonadotropin-releasing hormone agonist (GnRH-a), as well as the risk factors for premature spontaneous ovulation. Methods The rates of premature spontaneous ovulation in a total of 10 612 cycles using GnRH-ant or GnRH-a were compared. Matched case-controlled study and binary logistic regression model were conducted to analyze the risk factors for premature spontaneous ovulation. Results The spontaneous ovulation rate in the whole for GnRH-a cycles was 0.15%(13/8 514), compared with a 1.62%(34/2 098) in GnRH-ant cycles (P<0.01). Further matched controlled study and regression analyze found out that higher basal FSH level was a predominant risk and prediction factor for spontaneous ovulation (OR=1.20, P=0.009). Conclusions In GnRH-ant cycles, spontaneous ovulation rate is about 10 times than which in GnRH-a cycles. Diminished ovarian function is a predominate risk factor for premature spontaneous ovulation.%目的:探讨在体外受精-胚胎移植(IVF-ET)周期中促性腺激素释放激素拮抗剂(GnRH-ant)方案的自发排卵率,并分析自发排卵的高危因素。方法回顾性分析2012年1月至2015年12月中山大学附属第一医院在LVF-ET中使用GnRH-ant方案和促性腺激素释放激素激动剂(GnRH-a)长方案共10612个周期,计算GnRH-ant方案(2098个周期)的自发排卵总体情况,并与GnRH-a长方案(8514个周期)比较;进一步将GnRH-ant方案中发生自发排卵(自发排卵组)的周期(34个)与未发生自发排卵(未自发排卵组)的周期(136个)进行1∶4匹配的对照研究及二元logistic多因素回归分析,分析在GnRH-ant方案中发生自发排卵的高危因素。结果在总体人群中,GnRH-ant方案的自发排卵率为1.62%(34/2098),高于GnRH-a长方案的0.15%

  8. Clinical outcomes of prolonged gonadotropin-releasing hormone agonist(GnRH-a) therapy used in patients with good ovarian reserves and previous in vitro fertilization or intracytoplasmic sperm injection embryo transfer(IVF/ICSI-ET) failure cycle%超长方案在卵巢储备良好前次IVF/ICSI-ET失败患者中的应用分析

    Institute of Scientific and Technical Information of China (English)

    聂玲; 伍琼芳; 张寅; 陈晶晶

    2011-01-01

    Objective : To evaluate the clinical outcomes of prolonged gonadotropm-releasing hormone agonist therapy( GnRH-a) used in patients with good ovanan reserves and previous in vitro fertilization or intracytoplasmic sperm injection embryo transfer( IVF/ICSI-ET) failure cycle. Methods : Retrospective analyze a total of 246 patients with previous IVF-ET failure cycle and good ovarian reserve who underwent the secondary IVF-ET cycles. Patients were divided into two groups : the study group included 52 patients applied with prolonged protocol;the control group included 194 patients applied with long protocol. Results : The numher of oocytes retrieved and the duration of gonadotropin ( Gn) were significantly higher in the study group(P<0. 01). But there were no significant differences in the dose of Gn,total numher of good quality embryos, mean endometrium thickness on transfer day ,mean serum P level on human chorionic gonadotrophin ( HCG) day and severe ovarian hyperstimulation syndrome ( OHSS) rate between the two groups (P> 0. 05). The positive HCG rate and clinical pregnancy rate( CPR) increased obviously in the study group, respectively ( 79. l% vs 61. 1% , P =0. 03 ;69. 8% vs 54. 9% , P=O. 048 ) . And there was an mcreasing tendency in implantation rate ( 39. 5% vs 31. 5% , P = 0. 18 ) . Conclusion : Using prolonged gonadotropin-releasing hormone agonist therapy in patients with good ovarian reserves and previous IVF-ET failure cycle may make the endometrium receptivity better than using the long protocol, and improve obviously the clinical pregnancy outcomes. So the prolonged protocol is recommendable.%目的:评估超长降调节方案在卵巢储备良好前次IVF/ICSI-ET失败患者中的应用效果.方法:回顾分析246例卵巢储备功能良好前次IVF/ICSI-ET常规长方案失败再次行助孕治疗的患者,其中超长方案治疗52例为研究组,常规长方案治疗194例为对照组.结果:研究组Gn时间及

  9. Arg-Phe-amide-related peptides influence gonadotropin-releasing hormone neurons

    Institute of Scientific and Technical Information of China (English)

    Haluk Kelestimur; Emine Kacar; Aysegul Uzun; Mete Ozcan; Selim Kutlu

    2013-01-01

    The hypothalamic Arg-Phe-amide-related peptides, gonadotropin-inhibitory hormone and orthologous mammalian peptides of Arg-Phe-amide, may be important regulators of the hypothalamus-pituitary-gonadal reproductive axis. These peptides may modulate the effects of kisspeptins because they are presently recognized as the most potent activators of the hypothalamus-pituitary-gonadal axis. However, their effects on gonadotropin-releasing hormone neurons have not been investigated. In the current study, the GT1–7 cell line-expressing gonadotropin-releasing hormone was used as a model to explore the effects of Arg-Phe- amide-related peptides on kisspeptin activation. Intracellular calcium concentration was quantified using the calcium-sensitive dye, fura-2 acetoxymethyl ester. Gonadotropin-releasing hormone released into the medium was detected via enzyme-linked immunosorbent assay. Results showed that 100 nmol/L kisspeptin-10 significantly increased gonadotropin-releasing hormone levels (at 120 minutes of exposure) and intracellular calcium concentrations. Co-treatment of kisspeptin with 1 μmol/L gonadotropin-inhibitory hormone or 1 μmol/L Arg-Phe-amide-related peptide-1 significantly attenuated levels of kisspeptin-induced gonadotropin-releasing hormone but did not affect kisspeptin-induced elevations of intracellular calcium concentration. Overall, the results suggest that gonadotropin-inhibitory hormone and Arg-Phe-amide-related peptide-1 may have inhibitory effects on kisspeptin-activated gonadotropin-releasing hormone neurons independent of the calcium signaling pathway.

  10. The use of gonadotropin-releasing hormone antagonist post-ovulation trigger in ovarian hyperstimulation syndrome.

    Science.gov (United States)

    Chappell, Neil; Gibbons, William E

    2017-06-01

    The purpose of this paper is to assimilate all data pertaining to the use of gonadotropin-releasing hormone (GnRH) antagonists in in vitro fertilization cycles after ovulation trigger to reduce the symptoms of ovarian hyperstimulation syndrome (OHSS). A systematic review of the literature was performed to identify all studies performed on the use of a GnRH antagonist in IVF cycle post-ovulation trigger with patients at high risk for OHSS. Ten studies were identified and reviewed. Descriptions of the studies and their individual results are presented in the following manuscript. Due to significant heterogeneity among the studies, it was not possible to perform a group analysis. The use of GnRH antagonists post-ovulation trigger for treatment of OHSS has been considered for almost 20 years, though research into its use is sparse. Definitive conclusions and recommendations cannot be made at this time, though preliminary data from these trials demonstrate the potential for GnRH antagonists to play a role in the treatment of OHSS in certain patient populations.

  11. Life cycle assessment (LCA)

    DEFF Research Database (Denmark)

    Thrane, Mikkel; Schmidt, Jannick Andresen

    2004-01-01

    The chapter introduces Life Cycle Assessment (LCA) and its application according to the ISO 1404043 standards.......The chapter introduces Life Cycle Assessment (LCA) and its application according to the ISO 1404043 standards....

  12. Life cycle assessment (LCA)

    DEFF Research Database (Denmark)

    Thrane, Mikkel; Schmidt, Jannick Andresen

    2004-01-01

    The chapter introduces Life Cycle Assessment (LCA) and its application according to the ISO 1404043 standards.......The chapter introduces Life Cycle Assessment (LCA) and its application according to the ISO 1404043 standards....

  13. HIV Life Cycle

    Science.gov (United States)

    HIV Overview The HIV Life Cycle (Last updated 9/13/2016; last reviewed 9/8/2016) Key Points HIV gradually destroys the immune ... life cycle. What is the connection between the HIV life cycle and HIV medicines? Antiretroviral therapy (ART) ...

  14. Serum gonadotropins after gonadotropin-releasing hormone injection in bulls subjected to spacial restriction.

    Science.gov (United States)

    Gwazdauskas, F C; Bindas, E M; Anderson, G W; McGilliard, M L

    1984-12-01

    Response patterns of luteinizing hormone, follicle-stimulating hormone, and testosterone after injection of gonadotropin-releasing hormone were investigated in bulls grouped by weight (250 to 459 kg body weight) and confined five per pen in 9.2 or 6.4 m2 space per bull in two replicates. Blood samples were collected for 1 h prior to injection of 100 micrograms gonadotropin releasing hormone and 5 h after injection at 15-min intervals. Overall mean luteinizing hormone concentrations were not affected by spacial restriction or replicate. Interaction of treatment by time revealed that luteinizing hormone response curves were not similar. Restricted bulls had a higher response of luteinizing hormone to gonadotropin-releasing hormone. Follicle-stimulating hormone increased in all groups within 15 min and peaked at 219.4 ng/ml at 45 min. Both gonadotropin responses returned to preinjection concentrations by 4 h. Testosterone was affected by treatment, replicate, and time of sampling. Testosterone was higher in restricted bulls and higher in replicate 2. Mean testosterone peak following gonadotropin-releasing hormone was 3.86 ng/ml and occurred between 105 and 120 min which was approximately 90 min after the gonadotropin peaks. It appears that hormone responses to gonadotropin-releasing hormone were not depressed by spacial restriction, and additional spacial restriction of young bulls could be used commercially.

  15. 促性腺激素释放激素激动剂用于辅助生殖技术黄体支持的荟萃分析%Effect of luteal-phase gonadotropin-releasing hormone agonist administration on pregnancy outcome in IVF/ICSI cycles:a systematic review and Meta-analysis

    Institute of Scientific and Technical Information of China (English)

    余璐萍; 刘宁; 刘英

    2016-01-01

    目的系统评价促性腺激素释放激素激动剂(GnRH-a)用于辅助生殖技术(ART)黄体支持后,对妊娠结局产生的影响。方法计算机检索PubMed数据库、EMBASE数据库、Cochrane图书馆、随机对照试验(RCT)注册中心[WHO国际临床试验注册平台(ICTRP)和ClinicalTrials.gov]、中国生物医学文献数据库(CBM)、中国知网(CNKI)数据库及万方医学数据库中发表于2015年11月之前的原创性研究论文;收集在体外受精(IVF)或卵母细胞胞质内单精子注射(ICSI)中,GnRH-a应用于黄体支持的RCT文献。根据Cochrane系统评价方法,由2位评价员根据纳入及排除标准独立进行文献筛选、资料提取和质量评价后,采用Stata 13.0软件对符合质量标准的RCT文献进行荟萃分析,分析GnRH-a用于ART黄体支持后对妊娠结局产生的影响。结果共纳入11项研究,3406例患者,3280个周期。以采用标准黄体支持方案的研究人群为对照组,在标准黄体支持方案基础上加入GnRH-a的研究人群为试验组。试验组与对照组比较,出生率或继续妊娠率(RR=1.29,95%CI为1.11~1.51)、临床妊娠率(RR=1.24,95%CI为1.08~1.43)、多胎率(RR=1.95,95%CI为1.21~3.14)均明显增加。结论目前的证据表明,无论采用激动剂方案或拮抗剂方案降调,在黄体支持中加入GnRH-a均可增加出生率或继续妊娠率、临床妊娠率、多胎率,可为ART过程中的黄体支持提供新的治疗方案。%Objective To evaluate the potential efficacy and safety of gonadotropin-releasing hormone agonist(GnRH-a) administration in the luteal-phase on in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) cycles in assisted reproductive technology (ART). Methods The relevant papers published before November 2015 were electronically searched in PubMed, EMBASE, Cochrane Library, WHO ICTRP, ClinicalTrials.gov, CNKI, CBM and Wan

  16. Zebrafish adult-derived hypothalamic neurospheres generate gonadotropin-releasing hormone (GnRH) neurons

    Science.gov (United States)

    Cortés-Campos, Christian; Letelier, Joaquín; Ceriani, Ricardo; Whitlock, Kathleen E.

    2015-01-01

    ABSTRACT Gonadotropin-releasing hormone (GnRH) is a hypothalamic decapeptide essential for fertility in vertebrates. Human male patients lacking GnRH and treated with hormone therapy can remain fertile after cessation of treatment suggesting that new GnRH neurons can be generated during adult life. We used zebrafish to investigate the neurogenic potential of the adult hypothalamus. Previously we have characterized the development of GnRH cells in the zebrafish linking genetic pathways to the differentiation of neuromodulatory and endocrine GnRH cells in specific regions of the brain. Here, we developed a new method to obtain neural progenitors from the adult hypothalamus in vitro. Using this system, we show that neurospheres derived from the adult hypothalamus can be maintained in culture and subsequently differentiate glia and neurons. Importantly, the adult derived progenitors differentiate into neurons containing GnRH and the number of cells is increased through exposure to either testosterone or GnRH, hormones used in therapeutic treatment in humans. Finally, we show in vivo that a neurogenic niche in the hypothalamus contains GnRH positive neurons. Thus, we demonstrated for the first time that neurospheres can be derived from the hypothalamus of the adult zebrafish and that these neural progenitors are capable of producing GnRH containing neurons. PMID:26209533

  17. Ovarian hyperstimulation syndrome prevention strategies: use of gonadotropin-releasing hormone antagonists.

    Science.gov (United States)

    Griesinger, Georg

    2010-11-01

    The most serious complication of ovarian stimulation for in vitro fertilization is severe ovarian hyperstimulation syndrome (OHSS), a rare but potentially life-threatening condition. The present review discusses the place of gonadotropin-releasing hormone antagonists (GnRH-ant) in primary, secondary, and tertiary prevention of OHSS. Sound evidence indicates that the routine use of GnRH-ant instead of GnRH agonists (GnRHa) during ovarian stimulation drastically reduces the relative risk of OHSS. GnRH-ant are therefore useful for primary OHSS prevention, and an increased use of antagonists should help reduce the overall incidence of severe OHSS with its associated risks and complications. In patients on antagonist protocols identified to be at risk of developing severe OHSS, replacing human chorionic gonadotropin with GnRHa as a trigger of final oocyte maturation has been proposed as an effective measure of secondary prevention. A concept of combining GnRHa triggering with cryopreservation of all oocytes or embryos has yielded promising results as far as total avoidance of OHSS is concerned while providing a good chance of pregnancy for the patient in later frozen-thawed embryo transfers. In patients with early onset of OHSS, reinitiation of GnRH-ant in the luteal phase as a measure of tertiary prevention might lead to rapid regression of the syndrome; however only limited data on this new concept are available in the literature.

  18. Zebrafish adult-derived hypothalamic neurospheres generate gonadotropin-releasing hormone (GnRH neurons

    Directory of Open Access Journals (Sweden)

    Christian Cortés-Campos

    2015-09-01

    Full Text Available Gonadotropin-releasing hormone (GnRH is a hypothalamic decapeptide essential for fertility in vertebrates. Human male patients lacking GnRH and treated with hormone therapy can remain fertile after cessation of treatment suggesting that new GnRH neurons can be generated during adult life. We used zebrafish to investigate the neurogenic potential of the adult hypothalamus. Previously we have characterized the development of GnRH cells in the zebrafish linking genetic pathways to the differentiation of neuromodulatory and endocrine GnRH cells in specific regions of the brain. Here, we developed a new method to obtain neural progenitors from the adult hypothalamus in vitro. Using this system, we show that neurospheres derived from the adult hypothalamus can be maintained in culture and subsequently differentiate glia and neurons. Importantly, the adult derived progenitors differentiate into neurons containing GnRH and the number of cells is increased through exposure to either testosterone or GnRH, hormones used in therapeutic treatment in humans. Finally, we show in vivo that a neurogenic niche in the hypothalamus contains GnRH positive neurons. Thus, we demonstrated for the first time that neurospheres can be derived from the hypothalamus of the adult zebrafish and that these neural progenitors are capable of producing GnRH containing neurons.

  19. Consensus statement on the use of gonadotropin-releasing hormone analogs in children

    DEFF Research Database (Denmark)

    Carel, Jean-Claude; Eugster, Erica A; Rogol, Alan;

    2009-01-01

    OBJECTIVE: Gonadotropin-releasing hormone analogs revolutionized the treatment of central precocious puberty. However, questions remain regarding their optimal use in central precocious puberty and other conditions. The Lawson Wilkins Pediatric Endocrine Society and the European Society...... for Pediatric Endocrinology convened a consensus conference to review the clinical use of gonadotropin-releasing hormone analogs in children and adolescents. PARTICIPANTS: When selecting the 30 participants, consideration was given to equal representation from North America (United States and Canada) and Europe...... assembly for final review. If consensus could not be reached, conclusions were based on majority vote. All participants approved the final statement. CONCLUSIONS: The efficacy of gonadotropin-releasing hormone analogs in increasing adult height is undisputed only in early-onset (girls

  20. The effect of prolonged gonadotropin-releasing hormone agonist-induced down-regulation on pregnancy outcomes in frozen-thawed embryo transfer cycles for the patients with adenomyosis%促性腺激素释放激素激动剂超长降调节改善子宫腺肌病冻融胚胎移植妊娠结局的作用

    Institute of Scientific and Technical Information of China (English)

    冯云

    2011-01-01

    目的 评价促性腺激素释放激素激动剂(GnRH-a)超长垂体降调节对改善子宫腺肌病(AM)冻融胚胎移植(FET)周期妊娠结局的价值. 方法 将AM患者分为GnRH-a+人工周期组和单纯人工周期组,非AM患者行人工周期作为对照组.比较三组患者各项指标包括胚胎种植率、临床妊娠率、流产率、异位妊娠率差异. 结果 GnRH-a+人工周期子宫内膜准备方案明显提高AM患者FET周期胚胎种植率和临床妊娠率,而未增加流产率和异位妊娠率. 结论 GnRH-a超长降调节明显改善AM患者FET妊娠结局.%Objective:To evaluate the effect of prolonged gonadotropin-releasing hormone agonist (GnRH-a)-induced down-regulation on the outcomes of frozen-thawed embryo transfer (FET) cycles in the patients with adenomyosis.Methods:Patients with adenomyosis were divided into GnRH-a plus artificial cycle group (116 cycles) and simple artificial cycle group (106 cycles). Patients without adenomyosis who underwent artificial cycle before FET were grouped as controls (433 cycles). The pregnancy outcomes, including implantation rate, pregnancy rate, abortion rate and ectopic pregnancy rate of three groups were measured and compared.Results: GnRH-a down-regulation plus artificial cycle for endometrial preparation before FET significantly improved the implantation rate and pregnancy rate in adenomyosis patients, with no increase in the abortion rate or ectopic pregnancy rate.Conclusion: Prolonged GnRH-a therapy for down-regulation significantly improve the outcomes of FET cycles in adenomyosis patients.

  1. Life Cycle Environmental Management

    DEFF Research Database (Denmark)

    Pedersen, Claus Stig; Jørgensen, Jørgen; Pedersen, Morten Als

    1996-01-01

    processes. The discipline of life cycle environmental management (LCEM) focuses on the incorporation of environmental criteria from the life cycles of products and other company activities into the company management processes. This paper introduces the concept of LCEM as an important element...

  2. Life cycle management (LCM)

    DEFF Research Database (Denmark)

    2004-01-01

    The chapter gives an introduction to Life Cycle Management (LCM) and shows how LCM can be practiced in different contexts and at different ambition levels.......The chapter gives an introduction to Life Cycle Management (LCM) and shows how LCM can be practiced in different contexts and at different ambition levels....

  3. 76 FR 27888 - Implantation or Injectable Dosage Form New Animal Drugs; Gonadotropin Releasing Factor-Diphtheria...

    Science.gov (United States)

    2011-05-13

    ... drug regulations to reflect approval of a new animal drug application (NADA) filed by Pfizer, Inc. The NADA provides for the veterinary prescription use of gonadotropin releasing factor-diphtheria toxoid...-5755, filed NADA 141-322 that provides for the veterinary prescription use of IMPROVEST...

  4. 77 FR 4227 - Implantation or Injectable Dosage Form New Animal Drugs; Gonadotropin Releasing Factor Analog...

    Science.gov (United States)

    2012-01-27

    ... drug regulations to reflect approval of a supplemental new animal drug application (NADA) filed by Pfizer, Inc. The supplemental NADA extends the slaughter interval for intact male swine injected with..., filed a supplement to NADA 141-322 for IMPROVEST (gonadotropin releasing factor analog-diphtheria...

  5. HIV Life Cycle

    Science.gov (United States)

    ... Content HIV Replication Cycle Antiretroviral Drug Discovery and Development Need Help? Call 1-800-448-0440 (1 p.m. to 4 p.m. ET) Send us an email The HIV Life Cycle Last Reviewed: August 18, 2017 Key Points HIV gradually destroys the immune system by attacking and killing a type of white ...

  6. Negative Feedback Governs Gonadotrope Frequency-Decoding of Gonadotropin Releasing Hormone Pulse-Frequency

    OpenAIRE

    2009-01-01

    The synthesis of the gonadotropin subunits is directed by pulsatile gonadotropin-releasing hormone (GnRH) from the hypothalamus, with the frequency of GnRH pulses governing the differential expression of the common alpha-subunit, luteinizing hormone beta-subunit (LHbeta) and follicle-stimulating hormone beta-subunit (FSHbeta). Three mitogen-activated protein kinases, (MAPKs), ERK1/2, JNK and p38, contribute uniquely and combinatorially to the expression of each of these subunit genes. In this...

  7. Life Cycle Sustainability Dashboard

    DEFF Research Database (Denmark)

    Traverso, Marzia; Finkbeiner, Matthias; Jørgensen, Andreas

    2012-01-01

    One method to assess the sustainability performance of products is life cycle sustainability assessment (LCSA), which assesses product performance considering the environmental,economic, and social dimensions of the life cycle. The results of LCSA can be used to compare different products...... of sustainability is the communicability of the results by means of a graphical representation (a cartogram), characterized by a suitable chromatic scale and ranking score. The integration of LCSA and the dashboard of sustainability into a so-called Life Cycle Sustainability Dashboard (LCSD) is described here...... or to support decision making toward sustainable production and consumption. In both cases, LCSA results could be too disaggregated and consequently too difficult to understand and interpret by decision makers. As non-experts are usually the target audience of experts and scientists, and are also involved...

  8. Life Cycle Environmental Management

    DEFF Research Database (Denmark)

    Pedersen, Claus Stig; Jørgensen, Jørgen; Pedersen, Morten Als

    1996-01-01

    A precondition for environmentally conscious management is the awareness of the environmental impact potentials created by an industrial company. There is an obvious need for management tools to support the implementation of relevant environmental criteria into the industrial decision making...... processes. The discipline of life cycle environmental management (LCEM) focuses on the incorporation of environmental criteria from the life cycles of products and other company activities into the company management processes. This paper introduces the concept of LCEM as an important element...... of the complete set of environmental objects in an industrial manufacturing company....

  9. LIFE-CYCLE ASSESSMENT

    Science.gov (United States)

    Life Cycle Assessment, or LCA, is an environmental accounting and mangement approach that consider all the aspects of resource use and environmental releases associated with an industrial system from cradle-to-grave. Specifically, it is a holistic view of environmental interacti...

  10. Life Cycle Collection Management

    Directory of Open Access Journals (Sweden)

    Helen Shenton

    2003-09-01

    Full Text Available Life cycle collection management is a way of taking a long-term approach to the responsible stewardship of the British Library's collections and is one of the Library's strategic strands. It defines the different stages in a collection item's existence over time. These stages range from selection and acquisitions processing, cataloguing and press marking, through to preventive conservation, storage and retrieval. Life cycle collection management seeks to identify the costs of each stage in order to show the economic interdependencies between the phases over time. It thereby aims to demonstrate the long-term consequences of what the library takes into its collections, by making explicit the financial and other implications of decisions made at the beginning of the life cycle for the next 100 plus years. This paper describes the work over the past year at the British Library on this complex and complicated subject. It presents the emerging findings and suggests how it can be used for practical reasons (by individual curators and selectors and for economic, governance and political purposes. The paper describes the next steps in the project, for example, on a predictive data model. The British Library is seeking to benchmark itself against comparable organisations in this area. It intends to work with others on specific comparison for example, of life cycle costing of electronic and paper journals, as a prelude to eliding digital and 'traditional' formats.

  11. Mosquito Life Cycle

    Science.gov (United States)

    Knowing the stages of the mosquito's life will help you prevent mosquitoes around your home and help you choose the right pesticides for your needs, if you decide to use them. All mosquito species go through four distinct stages during their live cycle.

  12. Effects of a gonadotropin-releasing hormone vaccine on ovarian cyclicity and uterine morphology of an Asian elephant (Elephas maximus).

    Science.gov (United States)

    Boedeker, Nancy C; Hayek, Lee-Ann C; Murray, Suzan; de Avila, David M; Brown, Janine L

    2012-09-01

    This report describes the successful use of a gonadotropin-releasing hormone (GnRH) vaccine to suppress ovarian steroidogenic activity and to treat hemorrhage and anemia associated with reproductive tract pathology in a 59-year-old Asian elephant (Elephas maximus). The Repro-BLOC GnRH vaccine was administered subcutaneously as a series of 4 boosters of increasing dose from 3 to 30 mg of recombinant ovalbumin-GnRH fusion protein given at variable intervals after initial vaccination with 3 mg protein. Efficacy was confirmed over a year after initial vaccination based on complete ovarian cycle suppression determined by serum progestagen analyses. Estrous cycle suppression was associated with a significant increase in GnRH antibody binding and subsequent decrease in serum luteinizing hormone and follicle-stimulating hormone concentrations. Ultrasonographic examinations of the reproductive tract documented a reduction in uterine size and vascularity after immunization. The hematocrit level normalized soon after the initial intrauterine hemorrhage, and no recurrence of anemia has been detected. No substantive adverse effects were associated with GnRH vaccination. The results indicate that GnRH vaccination in elephants shows potential for contraception and management of uterine pathology in older elephants.

  13. Afferent neuronal control of type-I gonadotropin releasing hormone (GnRH neurons in the human

    Directory of Open Access Journals (Sweden)

    Erik eHrabovszky

    2013-09-01

    Full Text Available Understanding the regulation of the human menstrual cycle represents an important ultimate challenge of reproductive neuroendocrine research. However, direct translation of information from laboratory animal experiments to the human is often complicated by strikingly different and unique reproductive strategies and central regulatory mechanisms that can be present in even closely related animal species. In all mammals studied so far, type-I gonadotropin releasing hormone (GnRH synthesizing neurons form the final common output way from the hypothalamus in the neuroendocrine control of the adenohypophysis. Under various physiological and pathological conditions, hormonal and metabolic signals either regulate GnRH neurons directly or act on upstream neuronal circuitries to influence the pattern of pulsatile GnRH secretion into the hypophysial portal circulation. Neuronal afferents to GnRH cells convey important metabolic-, stress-, sex steroid-, lactational- and circadian signals to the reproductive axis, among other effects. This article gives an overview of the available neuroanatomical literature that described the afferent regulation of human GnRH neurons by peptidergic, monoaminergic and amino acidergic neuronal systems. Recent studies of human genetics provided evidence that central peptidergic signaling by kisspeptins and neurokinin B play particularly important roles in puberty onset and later, in the sex steroid-dependent feedback regulation of GnRH neurons. This review article places special emphasis on the topographic distribution, sexual dimorphism, aging-dependent neuroanatomical changes and plastic connectivity to GnRH neurons of the critically important human hypothalamic kisspeptin and neurokinin B systems.

  14. The Pneumocystis life cycle

    Directory of Open Access Journals (Sweden)

    Cécile-Marie Aliouat-Denis

    2009-05-01

    Full Text Available First recognised as "schizonts" of Trypanosoma cruzi, Pneumocystis organisms are now considered as part of an early-diverging lineage of Ascomycetes. As no robust long-term culture model is available, most data on the Pneumocystis cell cycle have stemmed from ultrastructural images of infected mammalian lungs. Although most fungi developing in animals do not complete a sexual cycle in vivo, Pneumocystis species constitute one of a few exceptions. Recently, the molecular identification of several key players in the fungal mating pathway has provided further evidence for the existence of conjugation and meiosis in Pneumocystisorganisms. Dynamic follow-up of stage-to-stage transition as well as studies of stage-specific proteins and/or genes would provide a better understanding of the still hypothetical Pneumocystislife cycle. Although difficult to achieve, stage purification seems a reasonable way forward in the absence of efficient culture systems. This mini-review provides a comprehensive overview of the historical milestones leading to the current knowledge available on the Pneumocystis life cycle.

  15. Improvement of chloride transport defect by gonadotropin-releasing hormone (GnRH in cystic fibrosis epithelial cells.

    Directory of Open Access Journals (Sweden)

    Nathalie Benz

    Full Text Available Cystic fibrosis (CF, the most common autosomal recessive disease in Caucasians, is due to mutations in the CFTR gene. F508del, the most frequent mutation in patients, impairs CFTR protein folding and biosynthesis. The F508del-CFTR protein is retained in the endoplasmic reticulum (ER and its traffic to the plasma membrane is altered. Nevertheless, if it reaches the cell surface, it exhibits a Cl(- channel function despite a short half-life. Pharmacological treatments may target the F508del-CFTR defect directly by binding to the mutant protein or indirectly by altering cellular proteostasis, and promote its plasma membrane targeting and stability. We previously showed that annexine A5 (AnxA5 directly binds to F508del-CFTR and, when overexpressed, promotes its membrane stability, leading to the restoration of some Cl(- channel function in cells. Because Gonadotropin-Releasing Hormone (GnRH increases AnxA5 expression in some cells, we tested it in CF cells. We showed that human epithelial cells express GnRH-receptors (GnRH-R and that GnRH induces an AnxA5 overexpression and an increased Cl(- channel function in F508del-CFTR cells, due to an increased stability of the protein in the membranes. Beside the numerous physiological implications of the GnRH-R expression in epithelial cells, we propose that a topical use of GnRH is a potential treatment in CF.

  16. The software life cycle

    CERN Document Server

    Ince, Darrel

    1990-01-01

    The Software Life Cycle deals with the software lifecycle, that is, what exactly happens when software is developed. Topics covered include aspects of software engineering, structured techniques of software development, and software project management. The use of mathematics to design and develop computer systems is also discussed. This book is comprised of 20 chapters divided into four sections and begins with an overview of software engineering and software development, paying particular attention to the birth of software engineering and the introduction of formal methods of software develop

  17. Gonadotropin-releasing hormone: regulation of the GnRH gene.

    Science.gov (United States)

    Lee, Vien H Y; Lee, Leo T O; Chow, Billy K C

    2008-11-01

    As the key regulator of reproduction, gonadotropin-releasing hormone (GnRH) is released by neurons in the hypothalamus, and transported via the hypothalamo-hypophyseal portal circulation to the anterior pituitary to trigger gonadotropin release for gonadal steroidogenesis and gametogenesis. To achieve appropriate reproductive function, mammals have precise regulatory mechanisms; one of these is the control of GnRH synthesis and release. In the past, the scarcity of GnRH neurons and their widespread distribution in the brain hindered the study of GnRH gene expression. Until recently, the development of GnRH-expressing cell lines with properties similar to those of in vivo GnRH neurons and also transgenic mice facilitated GnRH gene regulation research. This minireview provides a summary of the molecular mechanisms for the control of GnRH-I and GnRH-II gene expression. These include basal transcription regulation, which involves essential cis-acting elements in the GnRH-I and GnRH-II promoters and interacting transcription factors, and also feedback control by gonadotropins and gonadal sex steroids. Other physiological stimuli, e.g. insulin and melatonin, will also be discussed.

  18. Oxytocin/vasopressin and gonadotropin-releasing hormone from cephalopods to vertebrates.

    Science.gov (United States)

    Minakata, Hiroyuki

    2010-07-01

    Recent advances in peptide search methods have revealed two peptide systems that have been conserved through metazoan evolution. Members of the oxytocin/vasopressin-superfamily have been identified from protostomian and deuterostomian animals, indicating that the oxytocin/vasopressin hormonal system represents one of the most ancient systems. In most protostomian animals, a single member of the superfamily shares oxytocin-like and vasopressin-like actions. Co-occurrence of two members has been discovered in modern cephalopods, octopus, and cuttlefish. We propose that cephalopods have developed two peptides in the molluscan evolutionary lineage like vertebrates have established two lineages in the oxytocin/vasopressin superfamily. The existence of gonadotropin-releasing hormone (GnRH) in protostomian animals was initially suggested by immunohistochemical analysis using chordate GnRH antibodies. A peptide with structural features similar to those of chordate GnRHs was originally isolated from octopus, and an identical peptide has been characterized from squid and cuttlefish. Novel forms of GnRH-like molecules from other molluscs, an annelid, arthropods, and nematodes demonstrate somewhat conserved structures at the N-terminal regions; but structures of the C-terminal regions critical to gonadotropin-releasing activity are diverse. These findings may be important for the study of the molecular evolution of GnRH in protostomian animals.

  19. Treatment of canine pyometra with the gonadotropin-releasing hormone antagonist acyline: a case series.

    Science.gov (United States)

    Batista, Pablo R; Blanco, Paula G; Gobello, Cristina

    2015-03-01

    To describe the effect of the third-generation gonadotropin-releasing hormone antagonist acyline in the treatment of 4 diestrous bitches with the cystic endometrial hyperplasia-pyometra complex. The 4 bitches were treated with 330 μg/kg of subcutaneous acyline on day 0 and antibiotics, and followed up for 2 weeks. One closed-cervix case showed cervical dilatation 36 hours after treatment, and all the 4 animals showed resolution of clinical signs starting on day 3 posttreatment. Ultrasonographic uterine diameters and luminal contents decreased in the bitches having high progesterone serum concentrations before treatment but not in those with low levels. Serum progesterone importantly decreased from high to basal concentrations in the 3 "ultrasonographically cured" animals. No local or systemic side effects related to the treatment were observed. The gonadotropin-releasing hormone antagonist acyline may have a promising place for the medical treatment of cystic endometrial hyperplasia-pyometra complex in dogs. Copyright © 2015 Elsevier Inc. All rights reserved.

  20. Raloxifene Administration in Women Treated with Long Term Gonadotropin-releasing Hormone Agonist for Severe Endometriosis: Effects on Bone Mineral Density

    Science.gov (United States)

    Cho, Young Hwa; Um, Mi Jung; Kim, Suk Jin; Kim, Soo Ah

    2016-01-01

    Objectives To evaluate the efficacy of raloxifene in preventing bone loss associated with long term gonadotropin-releasing hormone agonist (GnRH-a) administration. Methods Twenty-two premenopausal women with severe endometriosis were treated with leuprolide acetate depot at a dosage of 3.75 mg/4 weeks, for 48 weeks. Bone mineral density (BMD) was evaluated at admission, and after 12 treatment cycles. Results At cycle 12 of GnRH-a plus raloxifene treatment, lumbar spine, trochanter femoral neck, and Ward's BMD differed from before the treatment. A year after treatment, the lumbar spine and trochanter decreased slightly, but were not significantly different. Conclusions Our study shows that the administration of GnRH-a plus raloxifene in pre-menopausal women with severe endometriosis, is an effective long-term treatment to prevent bone loss. PMID:28119898

  1. A regulator of G Protein signaling, RGS3, inhibits gonadotropin-releasing hormone (GnRH-stimulated luteinizing hormone (LH secretion

    Directory of Open Access Journals (Sweden)

    Musgrove Lois C

    2001-11-01

    Full Text Available Abstract Background Luteinizing hormone secreted by the anterior pituitary gland regulates gonadal function. Luteinizing hormone secretion is regulated both by alterations in gonadotrope responsiveness to hypothalamic gonadotropin releasing hormone and by alterations in gonadotropin releasing hormone secretion. The mechanisms that determine gonadotrope responsiveness are unknown but may involve regulators of G protein signaling (RGSs. These proteins act by antagonizing or abbreviating interaction of Gα proteins with effectors such as phospholipase Cβ. Previously, we reported that gonadotropin releasing hormone-stimulated second messenger inositol trisphosphate production was inhibited when RGS3 and gonadotropin releasing hormone receptor cDNAs were co-transfected into the COS cell line. Here, we present evidence for RGS3 inhibition of gonadotropin releasing hormone-induced luteinizing hormone secretion from cultured rat pituitary cells. Results A truncated version of RGS3 (RGS3T = RGS3 314–519 inhibited gonadotropin releasing hormone-stimulated inositol trisphosphate production more potently than did RSG3 in gonadotropin releasing hormone receptor-bearing COS cells. An RSG3/glutathione-S-transferase fusion protein bound more 35S-Gqα than any other member of the G protein family tested. Adenoviral-mediated RGS3 gene transfer in pituitary gonadotropes inhibited gonadotropin releasing hormone-stimulated luteinizing hormone secretion in a dose-related fashion. Adeno-RGS3 also inhibited gonadotropin releasing hormone stimulated 3H-inositol phosphate accumulation, consistent with a molecular site of action at the Gqα protein. Conclusions RGS3 inhibits gonadotropin releasing hormone-stimulated second messenger production (inositol trisphosphate as well as luteinizing hormone secretion from rat pituitary gonadotropes apparently by binding and suppressing the transduction properties of Gqα protein function. A version of RGS3 that is amino

  2. Assessing the adequacy of gonadotropin-releasing hormone agonist leuprolide to trigger oocyte maturation and management of inadequate response.

    Science.gov (United States)

    Chang, Frank E; Beall, Stephanie A; Cox, Jeris M; Richter, Kevin S; DeCherney, Alan H; Levy, Michael J

    2016-10-01

    To compare outcomes of in vitro fertilization (IVF) cycles with adequate versus inadequate response to the gonadotropin-releasing hormone (GnRH) agonist trigger rescued with the use of human chorionic gonadotropin (hCG) retrigger, and to identify risk factors associated with an inadequate trigger. Retrospective cohort study. Private practice. Women at high risk for ovarian hyperstimulation syndrome who underwent an autologous IVF cycle and used GnRH agonist to trigger oocyte maturation before oocyte retrieval. Patients were triggered with GnRH agonist for final oocyte maturation before retrieval. Patients with an inadequate response, defined by low post-trigger serum LH and P concentrations or failure to recover oocytes after aspiration of several follicles, were retriggered with hCG. Number of oocytes retrieved, fertilization rate, clinical pregnancy, and live birth. Two percent of patients triggered with GnRH agonist had an inadequate response and were retriggered with hCG. There was no statistically significant difference in clinical outcomes between the cycles that were retriggered with hCG and successful GnRH agonist triggers. Low body mass index, low baseline LH, and higher total dosage of gonadotropins required for stimulation were associated with an increased risk of having an inadequate response to the GnRH agonist trigger. A small minority of patients triggered with GnRH agonist had an inadequate response. Rescheduling of oocyte retrieval after hCG retrigger yielded similar IVF outcomes. Evaluation of trigger response based on serum LH and P concentrations is time dependent. Patient characteristics suggestive of hypothalamic hypofunction were predictive of an inadequate response to the GnRH agonist trigger. Copyright © 2016 American Society for Reproductive Medicine. All rights reserved.

  3. Ovarian hyperstimulation syndrome prevention strategies: oral contraceptive pills-dual gonadotropin-releasing hormone agonist suppression with step-down gonadotropin protocols.

    Science.gov (United States)

    Damario, Mark A

    2010-11-01

    The identification of patients at high risk for excessive responses to ovarian stimulation for in vitro fertilization and embryo transfer is essential in the tailoring of safe and effective treatment strategies. Known factors associated with increased sensitivity to gonadotropins include polycystic ovary syndrome, young age, prior ovarian hyperstimulation syndrome (OHSS), high baseline antral follicle count, and high baseline ovarian volume. Although several treatment strategies have been proposed for these patients, this report describes the experience using the dual suppression with gonadotropin step-down protocol. This protocol uses oral contraceptive pretreatment in combination with a long gonadotropin-releasing hormone agonist followed by a programmed step-down in gonadotropin dosing. Hormonal characteristics of dual suppression include an improved luteinizing hormone-to-follicle-stimulating hormone ratio and lower serum androgens, particularly dehydroepiandrosterone sulfate. Clinical characteristics of the protocol include a lower cancellation rate and favorable clinical and ongoing pregnancy rates per initiated cycle while mitigating the risk of OHSS.

  4. Molecular Mechanisms of Gonadotropin-Releasing Hormone Signaling: Integrating Cyclic Nucleotides into the Network

    Directory of Open Access Journals (Sweden)

    Craig Alexander McArdle

    2013-11-01

    Full Text Available Gonadotropin-releasing hormone (GnRH is the primary regulator of mammalian reproductive function in both males and females. It acts via G-protein coupled receptors on gonadotropes to stimulate synthesis and secretion of the gonadotropin hormones luteinizing hormone and follicle-stimulating hormone. These receptors couple primarily via G-proteins of the Gq/11 family, driving activation of phospholipase C and mediating GnRH effects on gonadotropin synthesis and secretion. There is also good evidence that GnRH causes activation of other heterotrimeric G-proteins (Gs and Gi with consequent effects on cyclic AMP production, as well as for effects on the soluble and particulate guanylyl cyclases that generate cGMP. Here we provide an overview of these pathways. We emphasise mechanisms underpinning pulsatile hormone signaling and the possible interplay of GnRH and autocrine or paracrine regulatory mechanisms in control of cyclic nucleotide signaling.

  5. Intraperitoneal administration of gonadotropin-releasing hormone-PE40 induces castration in male rats

    Institute of Scientific and Technical Information of China (English)

    Li Yu; Zhong-Fang Zhang; Chun-Xia Jing; Feng-Lin Wu

    2008-01-01

    AIM: To evaluate the long-term effects of gonadotropin-releasing hormone (GnRH)-based vaccine on levels of GnRH antibody and testosterone, and vaccine-induced immunocastration on sexual behavior of male rats.METHODS: The rats were treated with GnRH-PE40 intraperitoneally every other day for 12 wk. GnRH antibody and testosterone level in rat blood were determined by ELISA and radioimmunoassay, respectively. Morphological changes in testes and sexual behavior of rats were evaluated.RESULTS: GnRH-PE40 induced a high production in GnRH antibody, decreased the serum testosterone level, testis atrophy and sexual function in rats.CONCLUSION: Intraperitoneal administration of GnRH-PE40 produces structural and functional castration of male rat reproductive system by inducing anti-GnRH antibody.

  6. Optimizing subcutaneous injection of the gonadotropin-releasing hormone receptor antagonist degarelix.

    Science.gov (United States)

    Barkin, Jack; Burton, Shelley; Lambert, Carole

    2016-02-01

    The gonadotropin-releasing hormone (GnRH) receptor antagonist degarelix has several unique characteristics compared to luteinizing hormone-releasing hormone (LHRH) analogs used in the management of prostate cancer. Notable differences of GnRH receptor antagonists include no flare reaction, and a more rapid suppression of testosterone, luteinizing hormone (LH), follicle stimulating hormone (FSH) and prostate-specific antigen (PSA) compared to LHRH analogs. Despite emerging evidence supporting the use of GnRH receptor antagonists over the more widely used LHRH analogs in the management of prostate cancer, physicians may be reluctant to prescribe degarelix. They may be concerned about patient complaints about injection-site reactions (ISRs). The subcutaneous injection of degarelix has been associated with a higher rate of ISRs compared with the intramuscular injections of LHRH analogs. This "How I Do It" article describes techniques and strategies that have been developed by physicians and nurses to reduce the discomfort associated with the subcutaneous delivery of degarelix.

  7. Active immunization against gonadotropin-releasing hormone : an effective tool to block the fertility axis in mammals

    NARCIS (Netherlands)

    Turkstra, Jouwert Anne

    2005-01-01

    Gonadotropin releasing hormone (GnRH) plays a pivotal role in fertility and reproduction in mammals. It induces the release of luteinising hormone (LH) en follicle stimulating hormone (FSH) from the pituitary. These hormones are responsible for gonadal steroid production and indirectly for gametogen

  8. P-fimbriae of Escherichia coli as carriers for gonadotropin releasing hormone: development of a recombinant contraceptive vaccine

    NARCIS (Netherlands)

    Zee, van der A.; Noordegraaf, C.V.; Bosch, van den H.; Gielen, J.; Bergmans, H.; Hoekstra, W.; Die, van I.

    1995-01-01

    The demand for an effective and low cost means of fertility control of domestic animals has raised interest in the development of contraceptive vaccines. A promising candidate for a vaccine component is the brain peptide gonadotropin releasing hormone (GnRH), which plays a central role in the regula

  9. Role of gonadotropin-releasing hormone analogues in metastatic male breast cancer: results from a pooled analysis.

    Science.gov (United States)

    Di Lauro, Luigi; Pizzuti, Laura; Barba, Maddalena; Sergi, Domenico; Sperduti, Isabella; Mottolese, Marcella; Amoreo, Carla Azzurra; Belli, Franca; Vici, Patrizia; Speirs, Valerie; Santini, Daniele; De Maria, Ruggero; Maugeri-Saccà, Marcello

    2015-05-17

    Male breast cancer is a rare malignancy. Despite the lack of prospectively generated data from trials in either the adjuvant or metastatic setting, patients are commonly treated with hormone therapies. Much controversy exists over the use of gonadotropin-releasing hormone analogues in metastatic male breast cancer patients. We conducted this study to provide more concrete ground on the use of gonadotropin-releasing hormone analogues in this setting. We herein present results from a pooled analysis including 60 metastatic male breast cancer patients treated with either an aromatase inhibitor or cyproterone acetate as a monotherapy (23 patients) or combined with a gonadotropin-releasing hormone analogue (37 patients). Overall response rate was 43.5% in patients treated with monotherapy and 51.3% with combination therapy (p = 0.6). Survival outcomes favored combination therapy in terms of median progression-free survival (11.6 months versus 6 months; p = 0.05), 1-year progression-free survival rate (43.2% versus 21.7%; p = 0.05), median overall survival (29.7 months versus 22 months; p = 0.05), and 2-year survival rate (64.9% versus 43.5%; p = 0.05). In metastatic male breast cancer patients, the combined use of gonadotropin-releasing hormone analogues and aromatase inhibitors or antiandrogens seems to be associated with greater efficacy, particularly in terms of survival outcomes, compared with monotherapy. Collectively, these results encourage considering these agents in the metastatic setting.

  10. Acute injection and chronic perfusion of kisspeptin elicit gonadotropins release but fail to trigger ovulation in the mare.

    Science.gov (United States)

    Decourt, Caroline; Caraty, Alain; Briant, Christine; Guillaume, Daniel; Lomet, Didier; Chesneau, Didier; Lardic, Lionel; Duchamp, Guy; Reigner, Fabrice; Monget, Philippe; Dufourny, Laurence; Beltramo, Massimiliano; Dardente, Hugues

    2014-02-01

    Kisspeptin has emerged as the most potent gonadotropin-releasing hormone (GnRH) secretagogue and appears to represent the penultimate step in the central control of reproduction. In the sheep, we showed that kisspeptin could be used to manipulate gonadotropin secretion and control ovulation. Prompted by these results, we decided to investigate whether kisspeptin could be used as an ovulation-inducing agent in another photoperiodic domestic mammal, the horse. Equine kisspeptin-10 (eKp10) was administered intravenously as bolus injections or short- to long-term perfusions to Welsh pony mares, either during the anestrus season or at various stages of the cycle during the breeding season. In all the experimental conditions, eKp10 reliably increased peripheral concentrations of both luteinizing hormone and follicle-stimulating hormone. The nature of the response to eKp10 was consistent across experimental conditions and physiological states: the increase in gonadotropins was always rapid and essentially transient even when eKp10 was perfused for prolonged periods. Furthermore, eKp10 consistently failed to induce ovulation in the mare. To gain insights into the underlying mechanisms, we used acute injections or perfusions of GnRH. We also cloned the equine orthologues of the kisspeptin precursor and Kiss1r; this was justified by the facts that the current equine genome assembly predicted an amino acid difference between eKp10 and Kp10 in other species while an equine orthologue for Kiss1r was missing altogether. In light of these findings, potential reasons for the divergence in the response to kisspeptin between ewe and mare are discussed. Our data highlight that kisspeptin is not a universal ovulation-inducing agent.

  11. The estrogen myth: potential use of gonadotropin-releasing hormone agonists for the treatment of Alzheimer's disease.

    Science.gov (United States)

    Casadesus, Gemma; Garrett, Matthew R; Webber, Kate M; Hartzler, Anthony W; Atwood, Craig S; Perry, George; Bowen, Richard L; Smith, Mark A

    2006-01-01

    Estrogen and other sex hormones have received a great deal of attention for their speculative role in Alzheimer's disease (AD), but at present a direct connection between estrogen and the pathogenesis of AD remains elusive and somewhat contradictory. For example, on one hand there is a large body of evidence suggesting that estrogen is neuroprotective and improves cognition, and that hormone replacement therapy (HRT) at the onset of menopause reduces the risk of developing AD decades later. However, on the other hand, studies such as the Women's Health Initiative demonstrate that HRT initiated in elderly women increases the risk of dementia. While estrogen continues to be investigated, the disparity of findings involving HRT has led many researchers to examine other hormones of the hypothalamic-pituitary-gonadal axis such as luteinising hormone (LH) and follicle-stimulating hormone. In this review, we propose that LH, rather than estrogen, is the paramount player in the pathogenesis of AD. Notably, both men and women experience a 3- to 4-fold increase in LH with aging, and LH receptors are found throughout the brain following a regional pattern remarkably similar to those neuron populations affected in AD. With respect to disease, serum LH level is increased in women with AD relative to non-diseased controls, and levels of LH in the brain are also elevated in AD. Mechanistically, we propose that elevated levels of LH may be a fundamental instigator responsible for the aberrant reactivation of the cell cycle that is seen in AD. Based on these aforementioned aspects, clinical trials underway with leuprolide acetate, a gonadotropin-releasing hormone agonist that ablates serum LH levels, hold great promise as a ready means of treatment in individuals afflicted with AD.

  12. Life Cycle of Stars

    Science.gov (United States)

    1999-01-01

    In this stunning picture of the giant galactic nebula NGC 3603, the crisp resolution of NASA's Hubble Space Telescope captures various stages of the life cycle of stars in one single view. To the upper left of center is the evolved blue supergiant called Sher 25. The star has a unique circumstellar ring of glowing gas that is a galactic twin to the famous ring around the supernova 1987A. The grayish-bluish color of the ring and the bipolar outflows (blobs to the upper right and lower left of the star) indicates the presence of processed (chemically enriched) material. Near the center of the view is a so-called starburst cluster dominated by young, hot Wolf-Rayet stars and early O-type stars. A torrent of ionizing radiation and fast stellar winds from these massive stars has blown a large cavity around the cluster. The most spectacular evidence for the interaction of ionizing radiation with cold molecular-hydrogen cloud material are the giant gaseous pillars to the right of the cluster. These pillars are sculptured by the same physical processes as the famous pillars Hubble photographed in the M16 Eagle Nebula. Dark clouds at the upper right are so-called Bok globules, which are probably in an earlier stage of star formation. To the lower left of the cluster are two compact, tadpole-shaped emission nebulae. Similar structures were found by Hubble in Orion, and have been interpreted as gas and dust evaporation from possibly protoplanetary disks (proplyds). This true-color picture was taken on March 5, 1999 with the Wide Field Planetary Camera 2.

  13. The LifeCycle model

    DEFF Research Database (Denmark)

    Krink, Thiemo; Løvbjerg, Morten

    2002-01-01

    Adaptive search heuristics are known to be valuable in approximating solutions to hard search problems. However, these techniques are problem dependent. Inspired by the idea of life cycle stages found in nature, we introduce a hybrid approach called the LifeCycle model that simultaneously applies...

  14. Life Cycle of a Pencil.

    Science.gov (United States)

    Reeske, Mike

    2000-01-01

    Explains a project called "Life Cycle of a Pencil" which was developed by the National Science Teachers Association (NSTA) and the U.S. Environmental Protection Agency (USEPA). Describes the life cycle of a pencil in stages starting from the first stage of design to the sixth stage of product disposal. (YDS)

  15. Emissions from photovoltaic life cycles

    NARCIS (Netherlands)

    Fthenakis, V.M.; Kim, H.C.; Alsema, E.A.

    2008-01-01

    Photovoltaic (PV) technologies have shown remarkable progress recently in terms of annual production capacity and life cycle environmental performances, which necessitate timely updates of environmental indicators. Based on PV production data of 2004–2006, this study presents the life-cycle greenhou

  16. The LifeCycle model

    DEFF Research Database (Denmark)

    Krink, Thiemo; Løvbjerg, Morten

    2002-01-01

    Adaptive search heuristics are known to be valuable in approximating solutions to hard search problems. However, these techniques are problem dependent. Inspired by the idea of life cycle stages found in nature, we introduce a hybrid approach called the LifeCycle model that simultaneously applies...

  17. Life cycle of mobile devices

    Directory of Open Access Journals (Sweden)

    T.V. Rohal

    2011-12-01

    Full Text Available Article is devoted features of life cycle of mobile devices. The article highlighted a number of disadvantages associated with managing the life cycle of the product. Disadvantages include the orientation is not on the quality of mobile devices and their design, the obsolescence of digital products. The article drew attention to the need for process improvement life cycle management of mobile devices. For since this type of product is now the most popular among the population, consumers are interested, first of all, quality, and only then, look good.

  18. Introducing Life Cycle Impact Assessment

    DEFF Research Database (Denmark)

    Hauschild, Michael Zwicky; Huijbregts, Mark AJ

    2015-01-01

    methodology projects and presents the international scientific discussions and methodological consensus attempts in consecutive working groups under the auspices of the Society of Environmental Toxicology and Chemistry (SETAC) as well as the UNEP/ SETAC Life Cycle Initiative, and the (almost) parallel......This chapter serves as an introduction to the presentation of the many aspects of life cycle impact assessment (LCIA) in this volume of the book series ‘LCA Compendium’. It starts with a brief historical overview of the development of life cycle impact assessment driven by numerous national LCIA...

  19. Towards Life Cycle Sustainability Assessment

    Directory of Open Access Journals (Sweden)

    Marzia Traverso

    2010-10-01

    Full Text Available Sustainability is nowadays accepted by all stakeholders as a guiding principle for both public policy making and corporate strategies. However, the biggest challenge for most organizations remains in the real and substantial implementation of the sustainability concept. The core of the implementation challenge is the question, how sustainability performance can be measured, especially for products and processes. This paper explores the current status of Life Cycle Sustainability Assessment (LCSA for products and processes. For the environmental dimension well established tools like Life Cycle Assessment are available. For the economic and social dimension, there is still need for consistent and robust indicators and methods. In addition to measuring the individual sustainability dimensions, another challenge is a comprehensive, yet understandable presentation of the results. The “Life Cycle Sustainability Dashboard” and the “Life Cycle Sustainability Triangle” are presented as examples for communication tools for both experts and non expert stakeholders.

  20. Total Product Life Cycle (TPLC)

    Data.gov (United States)

    U.S. Department of Health & Human Services — The Total Product Life Cycle (TPLC) database integrates premarket and postmarket data about medical devices. It includes information pulled from CDRH databases...

  1. Studies on the Life Cycle

    African Journals Online (AJOL)

    The life cycle of the honeybee, Apis mellifera adansonii, was studied in mangrove area by monitoring the developmental .... honey, beeswax and other bee products (Malaka and Fasasi, 2005 .... decline of castes in the affected colony, thereby.

  2. Total Product Life Cycle (TPLC)

    Data.gov (United States)

    U.S. Department of Health & Human Services — The Total Product Life Cycle (TPLC) database integrates premarket and postmarket data about medical devices. It includes information pulled from CDRH databases...

  3. Life Cycle Costing: An Introduction

    DEFF Research Database (Denmark)

    Rödger, Jan-Markus; Kjær, Louise Laumann; Pagoropoulos, Aris

    2018-01-01

    The chapter gives an introduction to life cycle costing (LCC) and how it can be used to support decision-making. It can form the economic pillar in a full life cycle sustainability assessment, but often system delimitations differ depending on the goal and scope of the study. To provide a profound...... Life Cycle Assessment (LCA) in terms of system delimitation. Differences are explained and addressed, and an overview is given of the main cost categories to consider from different user perspectives. As inventory data is often sensitive in financial analyses, a list of relevant databases is provided...... understanding this chapter describes several approaches and terms, fundamental principles and different types of costs. A brief introduction is given to conventional LCC and societal LCC but the main focus is on environmental Life Cycle Costing (eLCC) as the LCC approach that is compatible with environmental...

  4. Enzymatic tracer damage during the gonadotropin releasing hormone radioimmunoassay: analytical and immunological assessment

    Energy Technology Data Exchange (ETDEWEB)

    O' Conner, J.L.; Lapp, C.A.; Clary, A.R.

    1985-09-23

    Hypothalamic supernatants from 60 day female rats were fractionated from Sephadex G-200 columns. The radioimmunoassay (RIA) for gonadotropin releasing hormone (GnRH) detected an apparently cross-reacting high molecular weight substance. The substance caused apparent displacement of iodinated GnRH binding in dose response fashion; however, no biological activity was observed in pituitary cell cultures. In order to determine whether the depressed binding might be caused by enzymatic degradation of iodinated GnRH during the RIA incubation, iodinated GnRH was preincubated under RIA conditions with either buffer or increasing concentrations of the GnRH cross-reacting material. Aliquots were subjected to polyacrylamide gel electrophoresis (PAGE) and the gels slices counted. Identical aliquots were subsequently used as iodinated hormone in the RIA of known quantities of synthetic GnRH. Tracer damage during the RIA-like preincubation period was reflected in the subsequent PAGE studies as decreased counts per minute in the intact GnRH peak and in the RIA studies as over-estimated quantification of the GnRH standards. This report describes such damage during the GnRH RIA and the data misinterpretations which result. 30 references, 6 figures, 1 table.

  5. Internalization and recycling of receptor-bound gonadotropin-releasing hormone agonist in pituitary gonadotropes

    Energy Technology Data Exchange (ETDEWEB)

    Schvartz, I.; Hazum, E.

    1987-12-15

    The fate of cell surface gonadotropin-releasing hormone (GnRH) receptors on pituitary cells was studied utilizing lysosomotropic agents and monensin. Labeling of pituitary cells with a photoreactive GnRH derivative, (azidobenzoyl-D-Lys6)GnRH, revealed a specific band of Mr = 60,000. When photoaffinity-labeled cells were exposed to trypsin immediately after completion of the binding, the radioactivity incorporated into the Mr = 60,000 band decreased, with a concomitant appearance of a proteolytic fragment (Mr = 45,000). This fragment reflects cell surface receptors. Following GnRH binding, the hormone-receptor complexes underwent internalization, partial degradation, and recycling. The process of hormone-receptor complex degradation was substantially prevented by lysosomotropic agents, such as chloroquine and methylamine, or the proton ionophore, monensin. Chloroquine and monensin, however, did not affect receptor recycling, since the tryptic fragment of Mr = 45,000 was evident after treatment with these agents. This suggests that recycling of GnRH receptors in gonadotropes occurs whether or not the internal environment is acidic. Based on these findings, we propose a model describing the intracellular pathway of GnRH receptors.

  6. Antibodies against gonadotropin-releasing hormone in patients with posterior laryngitis.

    Science.gov (United States)

    Pendleton, Hillevi; Alm, Ragnar; Nordin Fredrikson, Gunilla; Ohlsson, Bodil

    2013-01-01

    Patients with functional gastrointestinal disorders express antibodies against gonadotropin-releasing hormone (GnRH) in serum. One common cause of posterior laryngitis (PL) is extra-esophageal reflux, but a functional etiology has also been suggested. The aim of this study was to scrutinize patients with PL with regard to the presence of GnRH antibodies and to examine the association between antibodies and symptoms and reflux. Consecutive PL patients were included after examination. Serum was analyzed for the presence of antibodies using an enzyme-linked immunosorbent assay (ELISA) method and expressed as relative units (RU). Two age- and gender-matched healthy subjects per case served as controls. The prevalence of IgM GnRH antibodies in patients was 35% compared with 28% in controls (P = 0.06), with higher levels in patients (0.8 (0.3-2.2) RU) than in controls (0.2 (0.1-0.6) RU) (P = 0.007). The corresponding IgG antibody prevalences were 43% and 4%, respectively (P = 0.001), with no difference in levels (P = 0.70). There was no association between antibodies and clinical findings.

  7. Effect of gonadotropin-releasing hormone antagonist on primordial follicle survival in the primate ovary.

    Science.gov (United States)

    Attaman, Jill; Arbogast, Laura K; Friedman, Chad I; Danforth, Douglas R

    2014-01-01

    To examine the effects of gonadotropin-releasing hormone (GnRH) antagonist on primordial follicle reserve in the primate ovary. A prospective basic research study in which 10 juvenile cynomolgus monkeys (Macaca fascicularis) had 1 ovary surgically removed. Six animals were then treated with the GnRH antagonist antide (1.0 mg/kg/day) for 14 days, and 4 animals were treated with vehicle. After treatment the contralateral ovary was removed and both ovaries were prepared for assessment of primordial, primary, and secondary follicle numbers. Antide treatment resulted in a modest (13%) but significant decrease in primordial follicle number in juvenile macaques (p = 0.048, n = 6). Three animals demonstrated a marked reduction in primordial follicles (19%, 25%, 36%) and 3 animals had no (primordial follicles after antide treatment. Control animals demonstrated no change in primordial follicle number following vehicle treatment. Antide had no effect on primary, secondary, or early antral follicle numbers and did not affect circulating estradiol concentrations. In contrast to mice, in which GnRH antagonist treatment markedly reduces primordial follicle reserve, the effect of antide in nonhuman primates was less dramatic and somewhat variable. These data suggest there may be a subset of animals susceptible to the adverse effects of GnRH antagonist on primordial follicle survival.

  8. Gonadotropin-releasing hormone is prerequisite for the constitutive expression of pituitary annexin A5.

    Science.gov (United States)

    Yonezawa, Tomohiro; Watanabe, Aiko; Kurusu, Shiro; Kawaminami, Mitsumori

    2015-01-01

    Annexin A5 (ANXA5), a member of the structurally related family of annexin proteins, is expressed in pituitary gonadotropes. We previously reported that ANXA5 expression is stimulated by gonadotropin-releasing hormone (GnRH). In the present study, we investigated ANXA5 expression in the anterior pituitary gland of GnRH-deficient mutant hypogonadal (hpg) mice. RT-PCR demonstrated that luteinizing hormone β subunit (LHβ) and ANXA5 mRNA levels were both lower in the pituitary gland of hpg mice than in wild-type mice. Immunohistochemistry showed that ANXA5 expression throughout the pituitary gland was very low in hpg mice, suggesting that ANXA5 is diminished in gonadotropes and also in other cell types. Subcutaneous administration of a GnRH analogue, des-gly10 (Pro9)-GnRH ethylamide (1 μg/day for 7 days), augmented the expression of LHβ and ANXA5 in the pituitary gland in hpg mice. However, LHβ- and ANXA5-positive cells did not show exactly matched spatial distributions. These findings suggest that GnRH is necessary for constitutive ANXA5 expression in the pituitary gland, not only in gonadotropes but also in other pituitary gland cell types. A close relationship between ANXA5 and LHβ expression was confirmed. It is suggested that a significant role of ANXA5 in the physiologic secretion of LH.

  9. Ancient origins of metazoan gonadotropin-releasing hormone and their receptors revealed by phylogenomic analyses.

    Science.gov (United States)

    Plachetzki, David C; Tsai, Pei-San; Kavanaugh, Scott I; Sower, Stacia A

    2016-08-01

    The discovery of genes related to gonadotropin-releasing hormones (GnRH) and their receptors from diverse species has driven important advances in comparative endocrinology. However, our view of the evolutionary histories and nomenclature of these gene families has become inconsistent as several different iterations of GnRH and receptor relationships have been proposed. Whole genome sequence data are now available for most of the major lineages of animals, and an exhaustive view of the phylogenies of GnRH and their receptors is now possible. In this paper, we leverage data from publically available whole genome sequences to present a new phylogenomic analysis of GnRH and GnRH receptors and the distant relatives of each across metazoan phylogeny. Our approach utilizes a phylogenomics pipeline that searches data from 36 whole genome sequences and conducts phylogenetic analyses of gene trees. We provide a comprehensive analysis of the major groupings of GnRH peptides, related hormones and their receptors and provide some suggestions for a new nomenclature. Our study provides a framework for understanding the functional diversification of this family of neuromodulatory peptides and their receptors.

  10. Suppression of boar taint in cryptorchid pigs using a vaccine against the gonadotropin-releasing hormone.

    Science.gov (United States)

    Gutzwiller, A; Ampuero Kragten, S

    2013-12-01

    Thirteen unilaterally cryptorchid Large White pigs, which had been immunized at 4 and 8 weeks of age and a third time at 64 ± 4 kg body weight against the gonadotropin releasing hormone with the vaccine Improvac®, were slaughtered at the age of 170 ± 9 days at a body weight of 102 ± 12 kg. Twelve pigs tested negative in the olfactory test of the salivary gland; their descended testicles were small and their fat androstenone concentration was low compared to normally developed boars of a previous experiment which had been vaccinated twice with Improvac® according the manufacturer's recommendation. One cryptorchid boar, which tested positive in the olfactory test and whose testicular weight and fat androstenone concentration corresponded to values of unvaccinated boars of the same age, obviously had not responded to the vaccination. It is an open question if the vaccination protocol for normal boars is sufficient to prevent boar taint in the majority of cryptorchid pigs, too.

  11. Development of Gonadotropin-Releasing Hormone-Secreting Neurons from Human Pluripotent Stem Cells

    Directory of Open Access Journals (Sweden)

    Carina Lund

    2016-08-01

    Full Text Available Gonadotropin-releasing hormone (GnRH neurons regulate human puberty and reproduction. Modeling their development and function in vitro would be of interest for both basic research and clinical translation. Here, we report a three-step protocol to differentiate human pluripotent stem cells (hPSCs into GnRH-secreting neurons. Firstly, hPSCs were differentiated to FOXG1, EMX2, and PAX6 expressing anterior neural progenitor cells (NPCs by dual SMAD inhibition. Secondly, NPCs were treated for 10 days with FGF8, which is a key ligand implicated in GnRH neuron ontogeny, and finally, the cells were matured with Notch inhibitor to bipolar TUJ1-positive neurons that robustly expressed GNRH1 and secreted GnRH decapeptide into the culture medium. The protocol was reproducible both in human embryonic stem cells and induced pluripotent stem cells, and thus provides a translational tool for investigating the mechanisms of human puberty and its disorders.

  12. Morphological changes of gonadotropin-releasing hormone neurons in the rat preoptic area across puberty

    Institute of Scientific and Technical Information of China (English)

    Haogang Xue; Xiaodong Gai; Weiqi Sun; Chun Li; Quan Liu

    2014-01-01

    Gonadotropin-releasing hormone (GnRH) neurons in the preoptic area may undergo mor-phological changes during the pubertal period when their activities are upregulated. To clarify the regulatory mechanism of puberty onset, this study aimed to investigate the morphological changes of GnRH neurons in the preoptic area of GnRH-enhanced green lfuorescent protein transgenic rats. Under confocal laser microscopy, pubertal GnRH neurons exhibited an inverted Y distribution pattern. Prepubertal GnRH neurons were generally unipolar and bipolar, and were distinguished as smooth type cells with few small processes or irregular type cells with many spine-like processes in the proximal dendrites. The number of GnRH neurons in the preoptic area and spine-like processes were increased during the course of reproductive matu-ration. There was no signiifcant difference between male and female rats. Immunolfuorescence staining revealed synaptophysin punctae close to the distal end of GnRH neurons, indicating that some presynaptic terminals may form a synaptic linkage with these neurons.

  13. [Effect of bacterial endotoxin on migration of gonadotropin-releasing, hormone producing neurons in rat embryogenesis].

    Science.gov (United States)

    Sharova, V S; Izvol'skaia, M S; Voronova, S N; Zakharova, L A

    2011-01-01

    The effect of bacterial lipopolysaccharide endotoxin (LPS), immune system activator, on differentiation and migration of gonadotropin-releasing, hormone producing neurons in rat embryogenesis has been studied. Intraperitoneal introduction of LPS (18 jg/kg) to pregnant rats on the 12th day of pregnancy led to 50% decrease in total number of GRH-neurons in the forebrain of 17-day-old embryos and 17% decrease in 19-day-old embryos. At the same time, the number of GRH-neurons in the nasal area of the head of 17- and 19-day-old embryos increased by 40 and 50%, respectively, whereas it increased by 20% in olfactory bulbs of 17-day-old embryos and did not changed in olfactory bulbs of 19-day-old embryos. Neither the total number of neurons nor their distribution patterns were affected by the introduction of LPS into pregnant rats on the 15th day of pregnancy. Singular localization of GRH-neurons in embryo forebrain was observed after LPS administration, whereas the neurons were located by groups of 3-4 cells in rostral areas. Therefore, at the early stages of pregnancy, LPS was shown to suppress initial stages of differentiation and migration of GRH producing neurons. The effects observed in our study may be mediated by LPS-induced, proinflammatory cytokines.

  14. Gonadotropin-releasing hormone modulates cholesterol synthesis and steroidogenesis in SH-SY5Y cells.

    Science.gov (United States)

    Rosati, Fabiana; Sturli, Niccolò; Cungi, Maria Chiara; Morello, Matteo; Villanelli, Fabio; Bartolucci, Gianluca; Finocchi, Claudia; Peri, Alessandro; Serio, Mario; Danza, Giovanna

    2011-04-01

    Neurosteroids are involved in Central Nervous System development, brain functionality and neuroprotection but little is known about regulators of their biosynthesis. Recently gonadotropins, Gonadotropin-releasing Hormone (GnRH) and their receptors have been localized in different brain regions, such as hippocampus and cortex. Using human neuronal-like cells we found that GnRH up-regulates the expression of key genes of cholesterol and steroid synthesis when used in a narrow range around 1.0 nM. The expression of Hydroxysterol D24-reductase (seladin-1/DHCR24), that catalyzes the last step of cholesterol biosynthesis, is increased by 50% after 90 min of incubation with GnRH. StAR protein and P450 side chain cleavage (P450scc) are up-regulated by 3.3 times after 90 min and by 3.5 times after 3 h, respectively. GnRH action is mediated by LH and 1.0 nM GnRH enhances the expression of LHβ as well. A two fold increase of cell cholesterol is induced after 90 min of GnRH incubation and 17β-estradiol (E2) production is increased after 24, 48 and 72 h. These data indicate for the first time that GnRH regulates both cholesterol and steroid biosynthesis in human neuronal-like cells and suggest a new physiological role for GnRH in the brain.

  15. Life cycle and textiles recycling

    OpenAIRE

    2011-01-01

    Within the vision of development of European textile and clothing industry for 2020 from the standpoint of the European Technology Platform (ETP), the paper analyzes a segment which includes life cycle and recycling of textiles. It is the fact that the complexity of new textile and clothing product has caused the development of new-higher standards. For this reason in development of highly innovative products, today is included also quality assurance during his whole life cycle starting from ...

  16. Microdose gonadotropin-releasing hormone agonist in the absence of exogenous gonadotropins is not sufficient to induce multiple follicle development.

    Science.gov (United States)

    Chung, Karine; Fogle, Robin; Bendikson, Kristin; Christenson, Kamilee; Paulson, Richard

    2011-01-01

    Because the effectiveness of the "microdose flare" stimulation protocol often is attributed to the dramatic endogenous gonadotropin release induced by the GnRH agonist, the aim of this study was to determine whether use of microdose GnRH agonist alone could induce multiple ovarian follicle development in normal responders. Based on these data, the duration of gonadotropin rise is approximately 24 to 48 hours and is too brief to sustain continued multiple follicle growth.

  17. The soil life cycle

    NARCIS (Netherlands)

    Leeuwen, van J.P.

    2016-01-01

    Soil is one of the most important natural resource for life on Earth and provides important ecosystem services, such as food production, carbon sequestration, water regulation and contaminant attenuation. Soil quality, defined as the soil’s ability to provide these services, is drastically red

  18. Final adult height of girls with central precocious puberty or early and fast puberty could be improved by treatment of gonadotropin-releasing hormone analogs

    Institute of Scientific and Technical Information of China (English)

    陈秋莉

    2013-01-01

    Objective To assess the efficacy and impact factors of treatment with Gonadotropin-releasing hormone analogs(GnRHa) in central precocious puberty(CPP)or early and fast puberty(EFP)girls in a retrospective unicenter study

  19. Estrogenic environmental endocrine-disrupting chemical effects on reproductive neuroendocrine function and dysfunction across the life cycle.

    Science.gov (United States)

    Dickerson, Sarah M; Gore, Andrea C

    2007-06-01

    Endocrine disrupting chemicals (EDCs) are natural or synthetic compounds that interfere with the normal function of an organism's endocrine system. Many EDCs are resistant to biodegradation, due to their structural stability, and persist in the environment. The focus of this review is on natural and artificial EDCs that act through estrogenic mechanisms to affect reproductive neuroendocrine systems. This endocrine axis comprises the hypothalamic gonadotropin-releasing hormone (GnRH), pituitary gonadotropins, and gonadal steroid hormones, including estrogens. Although it is not surprising that EDCs that mimic or antagonize estrogen receptors may exert actions upon reproductive targets, the mechanisms for these effects are complex and involve all three levels of the hypothalamic-pituitary-gonadal (HPG) system. Nevertheless, considerable evidence links exposure to estrogenic environmental EDCs with neuroendocrine reproductive deficits in wildlife and in humans. The effects of an EDC are variable across the life cycle of an animal, and are particularly potent when exposure occurs during fetal and early postnatal development. As a consequence, abnormal sexual differentiation, disrupted reproductive function, or inappropriate sexual behavior may be detected later in life. This review will cover the effects of two representative classes of estrogenic EDCs, phytoestrogens and polychlorinated biphenyls (PCBs), on neuroendocrine reproductive function, from molecules to behavior, across the vertebrate life cycle. Finally, we identify the gaps of knowledge in this field and suggest future directions for study.

  20. Antifreeze life cycle assessment (LCA

    Directory of Open Access Journals (Sweden)

    Kesić Jelena

    2005-01-01

    Full Text Available Antifreeze based on ethylene glycol is a commonly used commercial product The classification of ethylene glycol as a toxic material increased the disposal costs for used antifreeze and life cycle assessment became a necessity. Life Cycle Assessment (LCA considers the identification and quantification of raw materials and energy inputs and waste outputs during the whole life cycle of the analyzed product. The objectives of LCA are the evaluation of impacts on the environment and improvements of processes in order to reduce and/or eliminate waste. LCA is conducted through a mathematical model derived from mass and energy balances of all the processes included in the life cycle. In all energy processes the part of energy that can be transformed into some other kind of energy is called exergy. The concept of exergy considers the quality of different types of energy and the quality of different materials. It is also a connection between energy and mass transformations. The whole life cycle can be described by the value of the total loss of exergy. The physical meaning of this value is the loss of material and energy that can be used. The results of LCA are very useful for the analyzed products and processes and for the determined conditions under which the analysis was conducted. The results of this study indicate that recycling is the most satisfactory solution for the treatment of used antifreeze regarding material and energy consumption but the re-use of antifreeze should not be neglected as a solution.

  1. Gonadotropin-releasing hormone agonists cotreatment during chemotherapy in borderline ovarian tumor and ovarian cancer patients

    Institute of Scientific and Technical Information of China (English)

    ZHU Hong-lan; WANG Yan; LI Xiao-ping; WANG Chao-hua; WANG Yue; CUI Heng; WANG Jian-liu

    2013-01-01

    Background Recently,conservative surgery is acceptable in young patients with borderline ovarian tumor and ovarian cancer.The preservation of these patients' future fertility has been the focus of recent interest.This study aimed to observe the effect of gonadotropin-releasing hormone agonists (GnRHa) cotreatment during chemotherapy in borderline ovarian tumor and ovarian cancer patients.Methods Sixteen patients who were treated with fertility preservation surgery for borderline ovarian tumor and ovarian cancer and then administered GnRHa during chemotherapy in Peking University People's Hospital from January 2006 to July 2010 were retrospectively analyzed.This group was compared with a control group of 16 women who were treated concurrently with similar chemotherapy (n=5) without GnRHa or were historical controls (n=11).The disease recurrence,the menstruation status and reproductive outcome were followed up and compared between the two groups.Results There were no significant differences between both groups regarding age,body weight,height,marriage status,classification of the tumors,stage of the disease,as were the cumulative doses of each chemotherapeutic agent.One (1/16) patient in the study group while 2 (2/16) patients in the control group relapsed 2 years after conclusion of the primary treatment (P >0.05).All of the 16 women in the study group compared with 11 of the 16 patients in the control group resumed normal menses 6 months after the termination of the treatment (P <0.05).There were 4 spontaneous pregnancies in the study group while 2 in the control group,all of the neonates were healthy.Conclusions GnRHa administration before and during chemotherapy in borderline ovarian tumor and ovarian cancer patients who had undergone fertility preservation operation may bring up higher rates of spontaneous resumption of menses and a better pregnancy rate.Long-term follow up and large scale clinical studies are required.

  2. Binding properties of solubilized gonadotropin-releasing hormone receptor: role of carboxylic groups

    Energy Technology Data Exchange (ETDEWEB)

    Hazum, E.

    1987-11-03

    The interaction of /sup 125/I-buserelin, a superactive agonist of gonadotropin-releasing hormone (GnRH), with solubilized GnRH receptor was studied. The highest specific binding of /sup 125/I-buserelin to solubilized GnRH receptor is evident at 4/sup 0/C, and equilibrium is reached after 2 h of incubation. The soluble receptor retained 100% of the original binding activity when kept at 4 or 22/sup 0/C for 60 min. Mono- and divalent cations inhibited, in a concentration-dependent manner, the binding of /sup 125/I-buserelin to solubilized GnRH receptor. Monovalent cations require higher concentrations than divalent cations to inhibit the binding. Since the order of potency with the divalent cations was identical with that of their association constants to dicarboxylic compounds, it is suggested that there are at least two carboxylic groups of the receptor that participate in the binding of the hormone. The carboxyl groups of sialic acid residues are not absolutely required for GnRH binding since the binding of /sup 125/I-buserelin to solubilized GnRH receptor was only slightly affected by pretreatment with neuraminidase and wheat germ agglutinin. The finding that polylysines stimulate luteinizing hormone (LH) release from pituitary cell cultures with the same efficacy as GnRH suggest that simple charge interactions can induce LH release. According to these results, the authors propose that the driving force for the formation of the hormone-receptor complex is an ionic interaction between the positively charged amino acid arginine in position 8 and the carboxyl groups in the binding site.

  3. Apoptotic death of prostate cancer cells by a gonadotropin-releasing hormone-II antagonist.

    Directory of Open Access Journals (Sweden)

    Sumi Park

    Full Text Available Gonadotropin-releasing hormone-I (GnRH-I has attracted strong attention as a hormonal therapeutic tool, particularly for androgen-dependent prostate cancer patients. However, the androgen-independency of the cancer in advanced stages has spurred researchers to look for new medical treatments. In previous reports, we developed the GnRH-II antagonist Trp-1 to inhibit proliferation and stimulate the autophagic death of various prostate cancer cells, including androgen-independent cells. We further screened many GnRH-II antagonists to identify molecules with higher efficiency. Here, we investigated the effect of SN09-2 on the growth of PC3 prostate cancer cells. SN09-2 reduced the growth of prostate cancer cells but had no effect on cells derived from other tissues. Compared with Trp-1, SN09-2 conspicuously inhibited prostate cancer cell growth, even at low concentrations. SN09-2-induced PC3 cell growth inhibition was associated with decreased membrane potential in mitochondria where the antagonist was accumulated, and increased mitochondrial and cytosolic reactive oxygen species. SN09-2 induced lactate dehydrogenase release into the media and annexin V-staining on the PC3 cell surface, suggesting that the antagonist stimulated prostate cancer cell death by activating apoptotic signaling pathways. Furthermore, cytochrome c release from mitochondria to the cytosol and caspase-3 activation occurred in a concentration- and time-dependent manner. SN09-2 also inhibited the growth of PC3 cells xenotransplanted into nude mice. These results demonstrate that SN09-2 directly induces mitochondrial dysfunction and the consequent ROS generation, leading to not only growth inhibition but also apoptosis of prostate cancer cells.

  4. Negative feedback governs gonadotrope frequency-decoding of gonadotropin releasing hormone pulse-frequency.

    Directory of Open Access Journals (Sweden)

    Stefan Lim

    Full Text Available The synthesis of the gonadotropin subunits is directed by pulsatile gonadotropin-releasing hormone (GnRH from the hypothalamus, with the frequency of GnRH pulses governing the differential expression of the common alpha-subunit, luteinizing hormone beta-subunit (LHbeta and follicle-stimulating hormone beta-subunit (FSHbeta. Three mitogen-activated protein kinases, (MAPKs, ERK1/2, JNK and p38, contribute uniquely and combinatorially to the expression of each of these subunit genes. In this study, using both experimental and computational methods, we found that dual specificity phosphatase regulation of the activity of the three MAPKs through negative feedback is required, and forms the basis for decoding the frequency of pulsatile GnRH. A fourth MAPK, ERK5, was shown also to be activated by GnRH. ERK5 was found to stimulate FSHbeta promoter activity and to increase FSHbeta mRNA levels, as well as enhancing its preference for low GnRH pulse frequencies. The latter is achieved through boosting the ultrasensitive behavior of FSHbeta gene expression by increasing the number of MAPK dependencies, and through modulating the feedforward effects of JNK activation on the GnRH receptor (GnRH-R. Our findings contribute to understanding the role of changing GnRH pulse-frequency in controlling transcription of the pituitary gonadotropins, which comprises a crucial aspect in regulating reproduction. Pulsatile stimuli and oscillating signals are integral to many biological processes, and elucidation of the mechanisms through which the pulsatility is decoded explains how the same stimulant can lead to various outcomes in a single cell.

  5. Gonadotropin-releasing hormone 2 suppresses food intake in the zebrafish, Danio rerio

    Directory of Open Access Journals (Sweden)

    Ryo eNishiguchi

    2012-10-01

    Full Text Available Gonadotropin-releasing hormone (GnRH is an evolutionarily conserved neuropeptide with 10 amino acid residues, of which several structural variants exist. A molecular form known as GnRH2 ([His5 Trp7 Tyr8]GnRH, also known as chicken GnRH II is widely distributed in vertebrates except for rodents, and has recently been implicated in the regulation of feeding behavior in goldfish. However, the influence of GnRH2 on feeding behavior in other fish has not yet been studied. In the present study, therefore, we investigated the role of GnRH2 in the regulation of feeding behavior in a zebrafish model, and examined its involvement in food intake after intracerebroventricular (ICV administration. ICV injection of GnRH2 at 0.1 and 1 pmol/g body weight (BW induced a marked decrease of food consumption in a dose-dependent manner during 30 min after feeding. Cumulative food intake was significantly decreased by ICV injection of GnRH2 at 1 pmol/g BW during the 30-min post-treatment observation period. The anorexigenic action of GnRH2 was completely blocked by treatment with the GnRH type I receptor antagonist Antide at 50 pmol/g BW. We also examined the effect of feeding condition on the expression level of the GnRH2 transcript in the hypothalamus. Levels of GnRH2 mRNA obtained from fish that had been provided excess food for 7 days were higher than those in fish that had been fed normally. These results suggest that, in zebrafish, GnRH2 acts as an anorexigenic factor, as is the case in goldfish.

  6. Direct regulation of gonadotropin release by neurokinin B in tilapia (Oreochromis niloticus).

    Science.gov (United States)

    Biran, Jakob; Golan, Matan; Mizrahi, Naama; Ogawa, Satoshi; Parhar, Ishwar S; Levavi-Sivan, Berta

    2014-12-01

    Neurokinin B (NKB) was recently identified as a key regulator of reproduction in mammals and fish. Fish were found to possess a specific novel neurokinin termed NKF. To study the role of NKB/NKF in the regulation of fish reproduction and to investigate the role of NKB/NKF and their receptors in the piscine pituitary, we have identified the NKB/tachikinin 3 receptor (tac3r) system in tilapia. Bioinformatics and phylogenetic analyses have demonstrated that the tilapia holds 1 putative tac3 gene and 2 NKB receptor genes (tac3ra and tac3rb) that clustered with other piscine Tac3 and NKB receptor lineages. Furthermore, we found that in African cichlids, NKB peptides differ from other vertebrate NKBs in their C-terminal sequence, possessing isoleucine instead of valine as the X in the NKB FXGLM-NH2-terminal consensus sequence. Signal transduction analysis demonstrated that tilapia NKB (tiNKB), tiNKF, and human NKB activated both CRE-luc and SRE-luc transcriptional activity of both tilapia and human NKB receptors. Two hours after ip injection of tiNKB, the plasma levels of both FSH and LH were increased, whereas tiNKF was more effective in increasing LH levels. However, tiNKB was more effective than tiNKF in increasing both FSH and LH from tilapia pituitary dispersed cells. Using in situ hybridization and fluorescent immunohistochemistry, we have shown that LH cells possess tac3, tac3ra, and tac3rb mRNAs, whereas FSH cells possess mainly tac3rb and tac3ra and tac3 to a much lesser extent. These results suggest that the members of the NKB/tac3r system may serve as paracrine/autocrine regulators of gonadotropin release in fish pituitary.

  7. Negative feedback governs gonadotrope frequency-decoding of gonadotropin releasing hormone pulse-frequency.

    Science.gov (United States)

    Lim, Stefan; Pnueli, Lilach; Tan, Jing Hui; Naor, Zvi; Rajagopal, Gunaretnam; Melamed, Philippa

    2009-09-29

    The synthesis of the gonadotropin subunits is directed by pulsatile gonadotropin-releasing hormone (GnRH) from the hypothalamus, with the frequency of GnRH pulses governing the differential expression of the common alpha-subunit, luteinizing hormone beta-subunit (LHbeta) and follicle-stimulating hormone beta-subunit (FSHbeta). Three mitogen-activated protein kinases, (MAPKs), ERK1/2, JNK and p38, contribute uniquely and combinatorially to the expression of each of these subunit genes. In this study, using both experimental and computational methods, we found that dual specificity phosphatase regulation of the activity of the three MAPKs through negative feedback is required, and forms the basis for decoding the frequency of pulsatile GnRH. A fourth MAPK, ERK5, was shown also to be activated by GnRH. ERK5 was found to stimulate FSHbeta promoter activity and to increase FSHbeta mRNA levels, as well as enhancing its preference for low GnRH pulse frequencies. The latter is achieved through boosting the ultrasensitive behavior of FSHbeta gene expression by increasing the number of MAPK dependencies, and through modulating the feedforward effects of JNK activation on the GnRH receptor (GnRH-R). Our findings contribute to understanding the role of changing GnRH pulse-frequency in controlling transcription of the pituitary gonadotropins, which comprises a crucial aspect in regulating reproduction. Pulsatile stimuli and oscillating signals are integral to many biological processes, and elucidation of the mechanisms through which the pulsatility is decoded explains how the same stimulant can lead to various outcomes in a single cell.

  8. Gonadotropin releasing hormone in the primitive vertebrate family Myxinidae: reproductive neuroanatomy and evolutionary aspects.

    Science.gov (United States)

    Sills, Eric Scott; Palermo, Gianpiero D

    2013-01-01

    The family Myxinidae embraces all hagfish species, and occupies an evolutionary niche intermediate between ancestral vertebrates and the gnathostomes (jawed vertebrates). Gonadotropin releasing hormone (GnRH) modulates neuroendocrine activity in vertebrates and works in the context of the hypothalamic-pituitary (H-P) axis. The appearance of this neuroendocrine axis marks one of the most crucial developmental achievements in vertebrate evolution, because it enabled further diversification in general growth, metabolism, osmoregulation and reproduction as jawed vertebrates evolved. GnRH studies in hagfish draw attention because such work may be considered as providing proxy data for similar investigations conducted upon long extinct species. Indeed, the fossil record reveals little anatomical difference between those hagfish living 300 million years ago and their modern descendants. Accordingly, the hagfish can offer important evolutionary lessons as they have some highly unusual characteristics not seen in any other vertebrate; they retain many representative features of an ancestral state from which all vertebrates originated. Indeed, because central control of reproduction is perhaps the most basic function of the vertebrate H-P axis, and given the importance of GnRH in this network, research on GnRH in hagfish can help elucidate the early evolution of the H-P system itself. Like all vertebrates, hagfish have a functional hypothalamic area and a pituitary gland, constituting a basic H-P axis. But what role does GnRH play in the reproductive system of this "living fossil"? How can understanding GnRH in hagfish help advance the knowledge of vertebrate neuroendocrinology? Here, information on neuroendocrine function and the role of GnRH specifically in this very basal vertebrate is reviewed.

  9. Gonadotropin-releasing hormone agonist use in men without a cancer registry diagnosis of prostate cancer

    Directory of Open Access Journals (Sweden)

    Kuo Yong-fang

    2008-07-01

    Full Text Available Abstract Background Use of gonadotropin-releasing hormone (GnRH agonists has become popular for virtually all stages of prostate cancer. We hypothesized that some men receive these agents after only a limited work-up for their cancer. Such cases may be missed by tumor registries, leading to underestimates of the total extent of GnRH agonist use. Methods We used linked Surveillance, Epidemiology and End-Results (SEER-Medicare data from 1993 through 2001 to identify GnRH agonist use in men with either a diagnosis of prostate cancer registered in SEER, or with a diagnosis of prostate cancer based only on Medicare claims (from the 5% control sample of Medicare beneficiaries residing in SEER areas without a registered diagnosis of cancer. The proportion of incident GnRH agonist users without a registry diagnosis of prostate cancer was calculated. Factors associated with lack of a registry diagnosis were examined in multivariable analyses. Results Of incident GnRH agonist users, 8.9% had no diagnosis of prostate cancer registered in SEER. In a multivariable logistic regression model, lack of a registry diagnosis of prostate cancer in GnRH agonist users was significantly more likely with increasing comorbidity, whereas it was less likely in men who had undergone either inpatient admission or procedures such as radical prostatectomy, prostate biopsy, or transurethral resection of the prostate. Conclusion Reliance solely on tumor registry data may underestimate the rate of GnRH agonist use in men with prostate cancer.

  10. Optimization of data life cycles

    Science.gov (United States)

    Jung, C.; Gasthuber, M.; Giesler, A.; Hardt, M.; Meyer, J.; Rigoll, F.; Schwarz, K.; Stotzka, R.; Streit, A.

    2014-06-01

    Data play a central role in most fields of science. In recent years, the amount of data from experiment, observation, and simulation has increased rapidly and data complexity has grown. Also, communities and shared storage have become geographically more distributed. Therefore, methods and techniques applied to scientific data need to be revised and partially be replaced, while keeping the community-specific needs in focus. The German Helmholtz Association project "Large Scale Data Management and Analysis" (LSDMA) aims to maximize the efficiency of data life cycles in different research areas, ranging from high energy physics to systems biology. In its five Data Life Cycle Labs (DLCLs), data experts closely collaborate with the communities in joint research and development to optimize the respective data life cycle. In addition, the Data Services Integration Team (DSIT) provides data analysis tools and services which are common to several DLCLs. This paper describes the various activities within LSDMA and focuses on the work performed in the DLCLs.

  11. Life cycle of remanufactured engines

    Institute of Scientific and Technical Information of China (English)

    YANG Ming; CHEN Ming

    2005-01-01

    The life cycle index of remanufactured engines was assessed by using the method of life cycle assessment (LCA). A remanufactured engine of a certain domestic brand was taken as researching object. Engine reproducing engineering was investigated from three aspects which were energy, material and environment. The application of LCA on remanufacturing engines was discussed in detail with a practical case. The results indicate that remanufackg CO2 , 6.09 kg CO, 1.01 kg NOx, 3. 985 kg SOx and 288. 725 kg solid waste. The remanufacturing of engines possesses great economic value and practicability.

  12. Menopause: A Life Cycle Transition.

    Science.gov (United States)

    Evarts, Barbara Kess; Baldwin, Cynthia

    1998-01-01

    Family therapists need to address the issue of menopause proactively to be of benefit to couples and families during this transitional period in the family life cycle. Physical, psychological, and psychosocial factors affecting the menopausal woman and her family, and ways to address these issues in counseling are discussed. (Author/EMK)

  13. Sourcing Life Cycle Inventory Data

    Science.gov (United States)

    The collection and validation of quality lifecycle inventory (LCI) data can be the most difficult and time-consuming aspect of developing a life cycle assessment (LCA). Large amounts of process and production data are needed to complete the LCI. For many studies, the LCA analyst ...

  14. The product life cycle revisited

    DEFF Research Database (Denmark)

    Ulhøi, John Parm

    1995-01-01

    Efter et introduktionsafsnit følger afsnit II, hvor der gives en historisk analyse af Life Cycle Assessment (LCA) og Environmental Impact Assessment (EIA). I afsnit III munder analysen ud i en vurdering af ligheder og forskelle mellem LCA analyser og EIA analyser, og en diskussion følger af...

  15. The product life cycle revisited

    DEFF Research Database (Denmark)

    Ulhøi, John Parm

    1995-01-01

    Efter et introduktionsafsnit følger afsnit II, hvor der gives en historisk analyse af Life Cycle Assessment (LCA) og Environmental Impact Assessment (EIA). I afsnit III munder analysen ud i en vurdering af ligheder og forskelle mellem LCA analyser og EIA analyser, og en diskussion følger af...

  16. Environmental life-cycle assessment

    Science.gov (United States)

    Kirchain, Randolph E., Jr.; Gregory, Jeremy R.; Olivetti, Elsa A.

    2017-07-01

    Concerns about the planet's health call for a careful evaluation of the environmental impact of materials choices. Life-cycle assessment is a tool that can help identify sustainable materials pathways by considering the burdens of materials both during production and as a product.

  17. Menopause: A Life Cycle Transition.

    Science.gov (United States)

    Evarts, Barbara Kess; Baldwin, Cynthia

    1998-01-01

    Family therapists need to address the issue of menopause proactively to be of benefit to couples and families during this transitional period in the family life cycle. Physical, psychological, and psychosocial factors affecting the menopausal woman and her family, and ways to address these issues in counseling are discussed. (Author/EMK)

  18. Sustainable Building Life Cycle Design

    Directory of Open Access Journals (Sweden)

    Ginzburg Alexander

    2016-01-01

    Full Text Available The current building life cycle management system in the Russian Federation is a family of discrete subsystems that exist independently for different building life cycle stages. In this situation building reliability and sustainable functioning are out of the question. The implementation of a united information model (BIM-model intended to describe building entire life cycle will allow to raise the sustainability, but this will happen only if goals and concerns of all participants of the project process are properly coordinated. An important figure of process sustainability is the organizational and technological reliability (OTR that describes the possibility of a system to reach a goal. In case of building life cycle design, the economical efficiency of a building can be considered as the goal. The required technical, ecological, organizational, and other parameters form a complex of constraints that determine the area of allowable values for building functioning. In its broad meaning, OTR may be understood as the probability of receiving an economical effect based on the value of organizational and economical reliability (OER.

  19. Glucocorticoid regulation of gonadotropin release from gonadotropes of ovine pituitary gland in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Nangalama, A.W.

    1989-01-01

    In order to understand the role of glucocorticoids in the regulation of gonadotropin release by the pituitary gland, the short-term effects of cortisol perifusion (1.5 h to 8 hrs) on GnRH-induced LH secretion were investigated. To determine the biochemical mechanism(s) by which cortisol can act to modulate GnRH-induced LH release, the interactions of cortisol and arachidonic acid in GnRH-stimulated LH release were examined. Cortisol perifusion for 1.5 hr had no effect on GnRH-induced LH release, but longer treatment periods (4 hr-8 hrs) significantly reduced GnRH-stimulated LH release (4.0 hr, p < 0.01; 6.0 hr, p < 0.001; 8.0 hr, p < 0.01). Treatment and animal effects were highly significant (p < 0.001). There were significant interactions (p < 0.001) between treatment and animal as determined by a two-way ANOVA. Cortisol treatment also produced progressive increases in basal LH secretion with time (1.5 hr, p < 0.05; 4.0 hr, p < 0.01; 6.0 hr, p < 0.01; 8.0 hr, p < 0.001). Incubation of pituitary tissue with arachidonic acid (AA) resulted in a linear dose-response of LH (p < 0.001). Cortisol infusion failed to inhibit GnRH-induced LH release in which 10{sup {minus}4}M AA was administered for 20 min before a 10 min, 10{sup {minus}10}M GnRH pulse. Like cortisol, chloroquine also failed to inhibit AA-induced LH release. Perifusion with 10{sup {minus}6}M cortisol for 6.0 hours significantly (p < 0.001) blocked GnRH-stimulated (H{sup 3})AA release 24% below the basal (100%) ({sup 3}H)AA secretion. Reduction of ({sup 3}H)AA release was accompanied by decreased GnRH-stimulated LH secretion.

  20. Conformation of an analog of human follicular gonadotropin releasing peptide TF14 in solution by 2D-NMR

    Institute of Scientific and Technical Information of China (English)

    吴宏伟; 翟纯; 王德心; 林克椿

    1996-01-01

    Since the discovery of hF-GRP, several analogs have been synthesized in order to see their effects on the gonadotropin releasing activity, either as agonists or antagonists to this peptide. TF14 is one of these analogs, whose 14th position in the primary sequence is Phe instead of Asn in hF-GRP, while its activity is doubled. 2D-NMR (TOCSY, ROESY) was used to determine the conformation of TF14 in solution. Compared with hF-GRP, the whole peptide is in a non-typical more extended conformation, which may give some due to the relation between structure and function of these two peptides.

  1. Functional Authentication of a Novel Gastropod Gonadotropin-Releasing Hormone Receptor Reveals Unusual Features and Evolutionary Insight

    OpenAIRE

    Kavanaugh, Scott I.; Tsai, Pei-San

    2016-01-01

    A gonadotropin-releasing hormone (GnRH)-like molecule was previously identified in a gastropod, Aplysia californica, and named ap-GnRH. In this study, we cloned the full-length cDNA of a putative ap-GnRH receptor (ap-GnRHR) and functionally authenticated this receptor as a bona fide ap-GnRHR. This receptor contains two potential translation start sites, each accompanied by a Kozak sequence, suggesting the translation of a long and a short form of the receptor is possible. The putative ap-GnRH...

  2. Efficacy of corifollitropin alfa followed by recombinant follicle-stimulating hormone in a gonadotropin-releasing hormone antagonist protocol for Korean women undergoing assisted reproduction.

    Science.gov (United States)

    Park, Hyo Young; Lee, Min Young; Jeong, Hyo Young; Rho, Yong Sook; Song, Sang Jin; Choi, Bum-Chae

    2015-06-01

    To evaluate the effect of a gonadotropin-releasing hormone (GnRH) antagonist protocol using corifollitropin alfa in women undergoing assisted reproduction. Six hundred and eighty-six in vitro fertilization-embryo transfer (IVF)/intracytoplasmic sperm injection (ICSI) cycles were analyzed. In 113 cycles, folliculogenesis was induced with corifollitropin alfa and recombinant follicle stimulating hormone (rFSH), and premature luteinizing hormone (LH) surges were prevented with a GnRH antagonist. In the control group (573 cycles), premature LH surges were prevented with GnRH agonist injection from the midluteal phase of the preceding cycle, and ovarian stimulation was started with rFSH. The treatment duration, quality of oocytes and embryos, number of embryo transfer (ET) cancelled cycles, risk of ovarian hyperstimulation syndrome (OHSS), and the chemical pregnancy rate were evaluated in the two ovarian stimulation protocols. There were no significant differences in age and infertility factors between treatment groups. The treatment duration was shorter in the corifollitropin alfa group than in the control group. Although not statistically significant, the mean numbers of matured (86.8% vs. 85.1%) and fertilized oocytes (84.2% vs. 83.1%), good embryos (62.4% vs. 60.3%), and chemical pregnancy rates (47.2% vs. 46.8%) were slightly higher in the corifollitropin alfa group than in the control group. In contrast, rates of ET cancelled cycles and the OHSS risk were slightly lower in the corifollitropin alfa group (6.2% and 2.7%) than in the control group (8.2% and 3.5%), although these differences were also not statistically significant. Although no significant differences were observed, the use of corifollitropin alfa seems to offer some advantages to patients because of its short treatment duration, safety, lower ET cancellation rate and reduced risk of OHSS.

  3. Postoperative Levonorgestrel-Releasing Intrauterine System Insertion After Gonadotropin-Releasing Hormone Agonist Treatment for Preventing Endometriotic Cyst Recurrence: A Prospective Observational Study.

    Science.gov (United States)

    Kim, Min Kyoung; Chon, Seung Joo; Lee, Jae Hoon; Yun, Bo Hyon; Cho, SiHyun; Choi, Young Sik; Lee, Byung Seok; Seo, Seok Kyo

    2017-01-01

    The aim of this study was to evaluate the effectiveness of postoperative levonorgestrel-releasing intrauterine system (LNG-IUS) insertion after gonadotropin-releasing hormone agonist (GnRH-a) treatment for preventing endometriotic cyst recurrence. The LNG-IUS was applied to 28 women who had undergone surgery for endometriosis followed by 6 cycles of GnRH-a treatment. Clinical characteristics, endometriosis recurrence, and adverse effects were analyzed. Student t test was performed for analysis. Before surgery, 20 (71.4%) patients had dysmenorrhea, and the mean pain score (visual analog scale [VAS]) was 4.26. The numbers of women diagnosed with stage III endometriosis and stage IV endometriosis were 15 (53.6%) and 13 (46.4%), respectively, according to the revised American Fertility Society scoring system. The mean cancer antigen 125 levels and VAS scores were significantly lower after treatment than before treatment (11.61 vs 75.66 U/mL, P < .0001 and 0.50 vs 4.26 U/mL, P < .0001, respectively). Of the 28 patients, 13 (46.4%) simultaneously had adenomyosis, and 2 (7.1%) underwent LNG-IUS removal because of unresolved vaginal bleeding and dysmenorrhea. Recurrence was noted in 2 (7.1%) women. Postoperative LNG-IUS insertion after GnRH-a treatment is an effective approach for preventing endometriotic cyst recurrence, especially in women who do not desire to conceive.

  4. Politics and the life cycle.

    Science.gov (United States)

    Kinder, Donald R

    2006-06-30

    The study of politics and the life cycle began with a rather single-minded focus on childhood and the family-on the idea, as Tocqueville famously put it, that the entire person could be "seen in the cradle of the child." Politics does begin in childhood, and parents do influence their offspring, but change takes place over the entire span of life. I take up the early emergence of partisanship and essentialism, the formation of generations, politically consequential transitions in adulthood, and the rising of politics and its final decline.

  5. Life cycle assessment of turbines

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2004-10-15

    This report forms part of the final reporting of the project 'LCA and turbines, which has been carried out as a cooperation between Vestas Wind Systems A/S and Tech-wise A/S on behalf of Elsam A/S. The goal of the project was to create a life cycle model for a big Vestas offshore turbine. Based on the offshore model an analysis has been prepared and this analysis will show the most significant environmental impacts a turbine will be subject to during its life cycle. Furthermore we have prepared a recommendation on how an improvement strategy on a selected area can be drafted. Finally, a preliminary environmental declaration of contents will be prepared for the turbine in question and 1 kWh generated from here. (BA)

  6. The regulation and function of fibroblast growth factor 8 and its function during gonadotropin-releasing hormone neuron development

    Directory of Open Access Journals (Sweden)

    Wilson CJ Chung

    2016-09-01

    Full Text Available Over the last few years, numerous studies solidified the hypothesis that fibroblast growth factor (FGF signaling regulates neuroendocrine progenitor cell proliferation, fate-specification, and cell survival, and therefore is critical for the regulation and maintenance of homeostasis of the body. One important example that underscores the involvement of FGF signaling during neuroendocrine cell development is gonadotropin-releasing hormone (GnRH neuron ontogenesis. Indeed, transgenic mice with reduced olfactory placode (OP Fgf8 expression do not have GnRH neurons. This observation indicates the requirement of FGF8 signaling for the emergence of the gonadotropin-releasing hormone (GnRH neuronal system in the embryonic OP, the putative birth place of GnRH neurons. Mammalian reproductive success depends on the presence of GnRH neurons to stimulate gonadotropin secretion from the anterior pituitary, which activates gonadal steroidogenesis and gametogenesis. Together, these observations are critical for understanding the function of GnRH neurons and their control of the hypothalamus-pituitary-gonadal (HPG axis to maintain fertility. Taken together, these studies illustrate that GnRH neuron emergence, and hence HPG-function is vulnerable to genomic and molecular signals that abnormally modify Fgf8 expression in the developing mouse OP. In this short review, we focus on research that is aimed at unraveling how androgen, all-trans retinoic acid and epigenetic modifies control mouse OP Fgf8 transcription in the context of GnRH neuronal development, and mammalian reproductive success.

  7. Life cycle management in product development

    DEFF Research Database (Denmark)

    Skelton, Kristen; Pattis, Anna

    The integration of Life Cycle Thinking (LCT) and Life Cycle Management (LCM) into business operations poses great challenges, as it requires a wider range of environmental responsibility often extending beyond a company's immediate control. Simultaneously, it offers many opportunities...

  8. The gonadotropin-releasing hormone antagonist protocol--the protocol of choice for the polycystic ovary syndrome patient undergoing controlled ovarian stimulation

    DEFF Research Database (Denmark)

    Kol, Shahar; Homburg, Roy; Alsbjerg, Birgit

    2012-01-01

    Polycystic ovary syndrome (PCOS) patients are prone to develop ovarian hyperstimulation syndrome (OHSS), a condition which can be minimized or completely eliminated by the use of a gonadotropin-releasing hormone agonist (GnRHa) trigger. In this commentary paper, we maintain that the gonadotropin-releasing...... hormone antagonist protocol should be the protocol of choice for the PCOS patient undergoing ovarian stimulation with gonadotropins for in vitro fertilization. If an excessive ovarian response is encountered, the clinician will always have two options: either to trigger final oocyte maturation...

  9. Effect of constant administration of a gonadotropin-releasing hormone agonist on reproductive activity in mares: preliminary evidence on suppression of ovulation during the breeding season.

    Science.gov (United States)

    Fitzgerald, B P; Peterson, K D; Silvia, P J

    1993-10-01

    During the breeding season, the effect of constant administration of an agonist analog of gonadotropin-releasing hormone (GnRH; goserelin acetate) on reproductive activity of mares was determined. Twenty-four mares undergoing estrous cycles were allocated at random to 6 groups (n = 4/group) and, on May 29 (day 0), received no treatment (group 1, controls), 120 micrograms (group 2), 360 micrograms (group 3), 600 micrograms (group 4), or 1,200 micrograms (group 5) of GnRH agonist/d for 28 days via a depot implanted subcutaneously. The final group of mares (group 6) was treated with 120 micrograms of GnRH agonist/d for 84 days (3 occasions at 28-day intervals). During a pretreatment period (April 19 to May 29) and for 90 days after initiation of GnRH agonist treatment, follicular development and ovulation were monitored by transrectal ultrasonography of the reproductive tract at 2- to 3-day intervals. On each occasion a blood sample was collected for determination of luteinizing hormone (LH) and progesterone. Estrous behavior was monitored by teasing of mares with a stallion. Initiation of agonist treatment was random, relative to the stage of the estrous cycle, and all mares ovulated within 11 days before or after implantation. In 3 of 4 nontreated control mares, estrous cycles were observed throughout the study, with interovulatory intervals ranging from 18 to 26 days. In the remaining mare, concentration of progesterone was high after asynchronous double ovulation during the pretreatment period, suggestive of persistent corpus luteum.(ABSTRACT TRUNCATED AT 250 WORDS)

  10. Life Cycle Assessment of Concrete

    Energy Technology Data Exchange (ETDEWEB)

    Sjunnesson, Jeannette

    2005-09-15

    This is an environmental study on concrete that follows the standard protocol of life cycle assessment (LCA). The study is done for two types of concrete, ordinary and frost-resistant concrete, and has an extra focus on the superplasticizers used as admixtures. The utilization phase is not included in this study since the type of construction for which the concrete is used is not defined and the concrete is assumed to be inert during this phase. The results show that it is the production of the raw material and the transports involved in the life cycle of concrete that are the main contributors to the total environmental load. The one single step in the raw material production that has the highest impact is the production of cement. Within the transportation operations the transportation of concrete is the largest contributor, followed by the transportation of the cement. The environmental impact of frost-resistant concrete is between 24-41 % higher than that of ordinary concrete due to its higher content of cement. Superplasticizers contribute with approximately 0.4-10.4 % of the total environmental impact of concrete, the least to the global warming potential (GWP) and the most to the photochemical ozone creation potential (POCP). Also the toxicity of the superplasticizers is investigated and the conclusion is that the low amount of leakage of superplasticizers from concrete leads to a low risk for the environment and for humans.

  11. Technology development life cycle processes.

    Energy Technology Data Exchange (ETDEWEB)

    Beck, David Franklin

    2013-05-01

    This report and set of appendices are a collection of memoranda originally drafted in 2009 for the purpose of providing motivation and the necessary background material to support the definition and integration of engineering and management processes related to technology development. At the time there was interest and support to move from Capability Maturity Model Integration (CMMI) Level One (ad hoc processes) to Level Three. As presented herein, the material begins with a survey of open literature perspectives on technology development life cycles, including published data on %E2%80%9Cwhat went wrong.%E2%80%9D The main thrust of the material presents a rational expose%CC%81 of a structured technology development life cycle that uses the scientific method as a framework, with further rigor added from adapting relevant portions of the systems engineering process. The material concludes with a discussion on the use of multiple measures to assess technology maturity, including consideration of the viewpoint of potential users.

  12. Social Life Cycle Assessment Revisited

    Directory of Open Access Journals (Sweden)

    Ruqun Wu

    2014-07-01

    Full Text Available To promote the development of Social Life Cycle Assessment (SLCA, we conducted a comprehensive review of recently developed frameworks, methods, and characterization models for impact assessment for future method developers and SLCA practitioners. Two previous reviews served as our foundations for this review. We updated the review by including a comprehensive list of recently-developed SLCA frameworks, methods and characterization models. While a brief discussion from goal, data, and indicator perspectives is provided in Sections 2 to 4 for different frameworks/methods, the focus of this review is Section 5 where discussion on characterization models for impact assessment of different methods is provided. The characterization models are categorized into two types following the UNEP/SETAC guidelines: type I models without impact pathways and type II models with impact pathways. Different from methods incorporating type I/II characterization models, another LCA modeling approach, Life Cycle Attribute Assessment (LCAA, is also discussed in this review. We concluded that methods incorporating either type I or type II models have limitations. For type I models, the challenge lies in the systematic identification of relevant stakeholders and materiality issues; while for type II models, identification of impact pathways that most closely and accurately represent the real-world causal relationships is the key. LCAA may avoid these problems, but the ultimate questions differ from those asked by the methods using type I and II models.

  13. Identification and distribution of gonadotropin-releasing hormone-like peptides in the brain of horseshoe crab Tachypleus tridentatus

    Institute of Scientific and Technical Information of China (English)

    HUANG Huiyang; LI Linming; YE Haihui; FENG Biyun; LI Shaojing

    2013-01-01

    Gonadotropin-releasing hormone (GnRH) is a crucial peptide for the regulation of reproduction.Using immunological techniques,we investigated the presence of GnRH in horseshoe crab Tachypleus tridentatus.Octopus GnRH-like immunoreactivity,tunicate GnRH-like immunoreactivity,and lamprey GnRH-I-like immunoreactivity were detected in the neurons and fibers of the protocerebrum.However,no mammal GnRH-like immunoreactivity or lamprey GnRH-Ⅲ-like immunoreactivity was observed.Our results suggest that a GnRH-like factor,an ancient peptide,existed in the brain of T.tridentatus and may be involved in the reproductive endocrine system.

  14. The effect of luteal phase gonadotropin-releasing hormone antagonist administration on IVF outcomes in women at risk of OHSS

    Science.gov (United States)

    Eftekhar, Maryam; Miraj, Sepideh; Mortazavifar, Zahrasadat

    2016-01-01

    Background: Gonadotropin-releasing hormone (GnRH) plays essential roles in embryo implantation, invasion of trophoblastic tissue, and steroid synthesis in the placenta. Objective: The aim of this study was to evaluate the effect of GnRH antagonist administration on pregnancy outcomes in early implantation period. Materials and Methods: In this retrospective study, 94 infertile women undergoing GnRH antagonist protocol who were at risk of ovarian hyperstimulation syndrome (OHSS) were included. Sixty-seven patients (group I) received Cetrorelix 0.25 mg/daily in the luteal phase for 3 days while in 27 participants (group II), it was not administered. Pregnancy outcomes were assessed based on chemical and clinical pregnancy rates. Results: The pregnancy outcomes were not significantly different between two groups (p=0.224). Conclusion: The present study proposed that luteal phase GnRH antagonist administration does not influence the chance of successful pregnancy outcomes. PMID:27679825

  15. Effects of oral contraceptives or a gonadotropin-releasing hormone agonist on ovarian carcinogenesis in genetically engineered mice.

    Science.gov (United States)

    Romero, Iris L; Gordon, Ilyssa O; Jagadeeswaran, Sujatha; Mui, Keeley L; Lee, Woo Seok; Dinulescu, Daniela M; Krausz, Thomas N; Kim, Helen H; Gilliam, Melissa L; Lengyel, Ernst

    2009-09-01

    Although epidemiologic evidence for the ability of combined oral contraception (OC) to reduce the risk of ovarian cancer (OvCa) is convincing, the biological mechanisms underlying this effect are largely unknown. We conducted the present study to determine if OC also influences ovarian carcinogenesis in a genetic mouse model and, if so, to investigate the mechanism underlying the protective effect. LSL-K-ras(G12D/+)Pten(loxP/loxP) mice were treated with ethinyl estradiol plus norethindrone, contraceptive hormones commonly used in combined OC, or norethindrone alone, or a gonadotropin-releasing hormone agonist. The combined OC had a 29% reduction in mean total tumor weight compared with placebo (epithelial tumor weight, -80%). Norethindrone alone reduced mean total tumor weight by 42% (epithelial tumor weight, -46%), and the gonadotropin-releasing hormone agonist increased mean total tumor weight by 71% (epithelial tumor weight, +150%). Large variations in tumor size affected the P values for these changes, which were not statistically significant. Nonetheless, the OC reductions are consistent with the epidemiologic data indicating a protective effect of OC. Matrix metalloproteinase-2 activity was decreased in association with OC, indicating that OC may affect ovarian carcinogenesis by decreasing proteolytic activity, an important early event in the pathogenesis of OvCa. In contrast, OC increased invasion in a K-ras/Pten OvCa cell line established from the mouse tumors, suggesting that OC hormones, particularly estrogen, may have a detrimental effect after the disease process is under way. Our study results support further investigation of OC effects and mechanisms for OvCa prevention.

  16. [Stimulation test of the adenohypophysis with arginine, gonadotropin-releasing hormone (GRH), and thyrotropin-releasing hormone (TRH) in 45, XO patients with Turner's syndrome (author's transl)].

    Science.gov (United States)

    Rudolf, K; Kyank, H; Göretzlehner, G; Kunkel, S

    1980-01-01

    Pituitary stimulation tests with arginine, gonadotropin-releasing hormone (GRH) and thyrotropin-releasing hormone (TRH) were performed in five 45, XO patients with Turner's syndrome. Their ages ranged from 12--17 years. Serum levels of LH, FSH, PRL, HGH, and TSH were measured by RIA. The hypothalamo-pituitary system appeared normal in the patients with Turner's syndrome.

  17. Life cycle of transformer oil

    Directory of Open Access Journals (Sweden)

    Đurđević Ksenija R.

    2008-01-01

    Full Text Available The consumption of electric power is constantly increasing due to industrialization and population growth. This results in much more severe operating conditions of transformers, the most important electrical devices that make integral parts of power transmission and distribution systems. The designed operating life of the majority of worldwide transformers has already expired, which puts the increase of transformer reliability and operating life extension in the spotlight. Transformer oil plays a very important role in transformer operation, since it provides insulation and cooling, helps extinguishing sparks and dissolves gases formed during oil degradation. In addition to this, it also dissolves moisture and gases from cellulose insulation and atmosphere it is exposed to. Further and by no means less important functions of transformer are of diagnostic purpose. It has been determined that examination and inspection of insulation oil provide 70% of information on transformer condition, which can be divided in three main groups: dielectric condition, aged transformer condition and oil degradation condition. By inspecting and examining the application oil it is possible to determine the condition of insulation, oil and solid insulation (paper, as well as irregularities in transformer operation. All of the above-mentioned reasons and facts create ground for the subject of this research covering two stages of transformer oil life cycle: (1 proactive maintenance and monitoring of transformer oils in the course of utilization with reference to influence of transformer oil condition on paper insulation condition, as well as the condition of the transformer itself; (2 regeneration of transformer oils for the purpose of extension of utilization period and paper insulation revitalization potential by means of oil purification. The study highlights advantages of oil-paper insulation revitalization over oil replacement. Besides economic, there are

  18. Life cycle of cytosolic prions.

    Science.gov (United States)

    Hofmann, Julia; Vorberg, Ina

    2013-01-01

    Prions are self-templating protein aggregates that were originally identified as the causative agent of prion diseases in mammals, but have since been discovered in other kingdoms. Mammalian prions represent a unique class of infectious agents that are composed of misfolded prion protein. Prion proteins usually exist as soluble proteins but can refold and assemble into highly ordered, self-propagating prion polymers. The prion concept is also applicable to a growing number of non-Mendelian elements of inheritance in lower eukaryotes. While prions identified in mammals are clearly pathogens, prions in lower eukaryotes can be either detrimental or beneficial to the host. Prion phenotypes in fungi are transmitted vertically from mother to daughter cells during cell division and horizontally during mating or abortive mating, but extracellular phases have not been reported. Recent findings now demonstrate that in a mammalian cell environment, protein aggregates derived from yeast prion domains exhibit a prion life cycle similar to mammalian prions propagated ex vivo. This life cycle includes a soluble state of the protein, an induction phase by exogenous prion fibrils, stable replication of prion entities, vertical transmission to progeny and natural horizontal transmission to neighboring cells. Our data reveal that mammalian cells contain all co-factors required for cytosolic prion propagation and dissemination. This has important implications for understanding prion-like properties of disease-related protein aggregates. In light of the growing number of identified functional amyloids, cell-to-cell propagation of cytosolic protein conformers might not only be relevant for the spreading of disease-associated proteins, but might also be of more general relevance under non-disease conditions.

  19. Different gonadotropin releasing hormone agonist doses for the final oocyte maturation in high-responder patients undergoing in vitro fertilization/intra-cytoplasmic sperm injection

    Directory of Open Access Journals (Sweden)

    Emre Goksan Pabuccu

    2015-01-01

    Full Text Available Context: Efficacy of gonadotropin releasing hormone agonists (GnRH-a for ovulation in high-responders. Aims: The aim of the current study is to compare the impact of different GnRH-a doses for the final oocyte maturation on cycle outcomes and ovarian hyperstimulation syndrome (OHSS rates in high-responder patients undergoing ovarian stimulation. Settings And Designs: Electronic medical records of a private in vitro fertilization center, a retrospective analysis. Subjects and Methods: A total of 77 high-responder cases were detected receiving GnRH-a. Group I consisted of 38 patients who received 1 mg of agonist and Group II consisted of 39 patients who received 2 mg of agonist. Statistical Analysis: In order to compare groups, Student′s t-test, Mann-Whitney U-test, Pearson′s Chi-square test or Fisher′s exact test were used where appropriate. A P < 0.05 was considered as statistically significant. Result: Number of retrieved oocytes (17.5 vs. 15.0, P = 0.510, implantation rates (46% vs. 55.1%, P = 0.419 and clinical pregnancy rates (42.1% vs. 38.5%, P = 0.744 were similar among groups. There were no mild or severe OHSS cases detected in Group I. Only 1 mild OHSS case was detected in Group II. Conclusion: A volume of 1 or 2 mg leuprolide acetate yields similar outcomes when used for the final oocyte maturation in high-responder patients.

  20. Does prolonged pituitary down-regulation with gonadotropin-releasing hormone agonist improve the live-birth rate in in vitro fertilization treatment?

    Science.gov (United States)

    Ren, Jianzhi; Sha, Aiguo; Han, Dongmei; Li, Ping; Geng, Jie; Ma, Chaihui

    2014-07-01

    To evaluate the effects of a prolonged duration of gonadotropin-releasing hormone agonist (GnRH-a) in pituitary down-regulation for controlled ovarian hyperstimulation (COH) on the live-birth rate in nonendometriotic women undergoing in vitro fertilization and embryo transfer (IVF-ET). Retrospective cohort study. University-affiliated hospital. Normogonadotropic women undergoing IVF. Three hundred seventy-eight patients receiving a prolonged pituitary down-regulation with GnRH-a before ovarian stimulation and 422 patients receiving a GnRH-a long protocol. Live-birth rate per fresh ET. In comparison with the long protocol, the prolonged down-regulation protocol required a higher total dose of gonadotropins. A lower serum luteinizing hormone (LH) level on the starting day of gonadotropin and the day of human chorionic gonadotropin (hCG) and a fewer number of oocytes and embryos were observed in the prolonged down-regulation protocol. However, the duration of stimulation and number of high-quality embryos were comparable between the two groups. A statistically significantly higher implantation rate (50.27% vs. 39.69%), clinical pregnancy rate (64.02% vs. 56.87%) and live-birth rate per fresh transfer cycle (55.56% vs. 45.73%) were observed in the prolonged protocol. Prolonged down-regulation in a GnRH-a protocol might increase the live-birth rates in normogonadotropic women. Copyright © 2014 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  1. General framework for bridge life cycle design

    Institute of Scientific and Technical Information of China (English)

    Junhai MA; Airong CHEN; Jun HE

    2009-01-01

    Based on a detailed illustration for bridge life cycle design which comprises the processes of service life design, aesthetics design, performance design, environ-mental and ecological design, inspection, maintenance and repair design as well as cost analysis, this paper presented a general framework for bridge life cycle design comprising three design phases and six design processes.

  2. Gonadotropin-releasing hormone receptor (Gnrhr) gene knock out: Normal growth and development of sensory, motor and spatial orientation behavior but altered metabolism in neonatal and prepubertal mice

    Science.gov (United States)

    Busby, Ellen R.; Sherwood, Nancy M.

    2017-01-01

    Gonadotropin-releasing hormone (GnRH) is important in the control of reproduction, but its actions in non-reproductive processes are less well known. In this study we examined the effect of disrupting the GnRH receptor in mice to determine if growth, metabolism or behaviors that are not associated with reproduction were affected. To minimize the effects of other hormones such as FSH, LH and sex steroids, the neonatal-prepubertal period of 2 to 28 days of age was selected. The study shows that regardless of sex or phenotype in the Gnrhr gene knockout line, there was no significant difference in the daily development of motor control, sensory detection or spatial orientation among the wildtype, heterozygous or null mice. This included a series of behavioral tests for touch, vision, hearing, spatial orientation, locomotory behavior and muscle strength. Neither the daily body weight nor the final weight on day 28 of the kidney, liver and thymus relative to body weight varied significantly in any group. However by day 28, metabolic changes in the GnRH null females compared with wildtype females showed a significant reduction in inguinal fat pad weight normalized to body weight; this was accompanied by an increase in glucose compared with wildtype females shown by Student-Newman-Keuls Multiple Comparison test and Student's unpaired t tests. Our studies show that the GnRH-GnRHR system is not essential for growth or motor/sensory/orientation behavior during the first month of life prior to puberty onset. The lack of the GnRH-GnRHR axis, however, did affect females resulting in reduced subcutaneous inguinal fat pad weight and increased glucose with possible insulin resistance; the loss of the normal rise of estradiol at postnatal days 15–28 may account for the altered metabolism in the prepubertal female pups. PMID:28346489

  3. Gonadotropin-releasing hormone receptor (Gnrhr) gene knock out: Normal growth and development of sensory, motor and spatial orientation behavior but altered metabolism in neonatal and prepubertal mice.

    Science.gov (United States)

    Busby, Ellen R; Sherwood, Nancy M

    2017-01-01

    Gonadotropin-releasing hormone (GnRH) is important in the control of reproduction, but its actions in non-reproductive processes are less well known. In this study we examined the effect of disrupting the GnRH receptor in mice to determine if growth, metabolism or behaviors that are not associated with reproduction were affected. To minimize the effects of other hormones such as FSH, LH and sex steroids, the neonatal-prepubertal period of 2 to 28 days of age was selected. The study shows that regardless of sex or phenotype in the Gnrhr gene knockout line, there was no significant difference in the daily development of motor control, sensory detection or spatial orientation among the wildtype, heterozygous or null mice. This included a series of behavioral tests for touch, vision, hearing, spatial orientation, locomotory behavior and muscle strength. Neither the daily body weight nor the final weight on day 28 of the kidney, liver and thymus relative to body weight varied significantly in any group. However by day 28, metabolic changes in the GnRH null females compared with wildtype females showed a significant reduction in inguinal fat pad weight normalized to body weight; this was accompanied by an increase in glucose compared with wildtype females shown by Student-Newman-Keuls Multiple Comparison test and Student's unpaired t tests. Our studies show that the GnRH-GnRHR system is not essential for growth or motor/sensory/orientation behavior during the first month of life prior to puberty onset. The lack of the GnRH-GnRHR axis, however, did affect females resulting in reduced subcutaneous inguinal fat pad weight and increased glucose with possible insulin resistance; the loss of the normal rise of estradiol at postnatal days 15-28 may account for the altered metabolism in the prepubertal female pups.

  4. Effective risk management SOGO life cycle management

    OpenAIRE

    Ali, Mohamed Omar

    2012-01-01

    After new or upgrade projects the offshore installation gets maintenance or support through the life cycle management organization at Siemens. Small to medium modification projects are executed by the life cycle management. Risk assessment on these projects show different risks when it comes to estimation and pricing of projects, planning and executing, resource management, competence and knowledge.

  5. LIFE CYCLE ASSESSMENT: PRINCIPLES AND PRACTICE

    Science.gov (United States)

    The following document provides an introductory overview of Life Cycle Assessment (LCA) and describes the general uses and major components of LCA. This document is an update and merger of two previous EPA documents on LCA ("Life Cycle Assessment: Inventory Guidelines and Princip...

  6. Effective risk management SOGO life cycle management

    OpenAIRE

    Ali, Mohamed Omar

    2012-01-01

    After new or upgrade projects the offshore installation gets maintenance or support through the life cycle management organization at Siemens. Small to medium modification projects are executed by the life cycle management. Risk assessment on these projects show different risks when it comes to estimation and pricing of projects, planning and executing, resource management, competence and knowledge.

  7. Life cycle assessment of greenhouse gas emissions

    NARCIS (Netherlands)

    Reijnders, L.; Chen, W.Y.; Seiner, J.; Suzuki, T.; Lackner, M.

    2012-01-01

    Life cycle assessments of greenhouse gas emissions have been developed for analyzing products "from cradle to grave": from resource extraction to waste disposal. Life cycle assessment methodology has also been applied to economies, trade between countries, aspects of production and to waste

  8. Life Cycle Assessment of Greenhouse Gas Emissions

    NARCIS (Netherlands)

    Reijnders, L.; Chen, W.Y.; Suzuki, T.; Lackner, M.

    2016-01-01

    Life cycle assessments of greenhouse gas emissions have been developed for analyzing products "from cradle to grave": from resource extraction to waste disposal. Life cycle assessment methodology has also been applied to economies, trade between countries, aspects of production, and waste

  9. Life-cycle assessment of semiconductors

    CERN Document Server

    Boyd, Sarah B

    2012-01-01

    Life-Cycle Assessment of Semiconductors presents the first and thus far only available transparent and complete life cycle assessment of semiconductor devices. A lack of reliable semiconductor LCA data has been a major challenge to evaluation of the potential environmental benefits of information technologies (IT). The analysis and results presented in this book will allow a higher degree of confidence and certainty in decisions concerning the use of IT in efforts to reduce climate change and other environmental effects. Coverage includes but is not limited to semiconductor manufacturing trends by product type and geography, unique coverage of life-cycle assessment, with a focus on uncertainty and sensitivity analysis of energy and global warming missions for CMOS logic devices, life cycle assessment of flash memory and life cycle assessment of DRAM. The information and conclusions discussed here will be highly relevant and useful to individuals and institutions. The book also: Provides a detailed, complete a...

  10. Effective embryo production from Holstein cows treated with gonadotropin-releasing hormone during early lactation.

    Science.gov (United States)

    Ogata, Yasuhiro; Yu, Guang-Min; Hidaka, Takemasa; Matzushige, Tadami; Maeda, Teruo

    2016-10-01

    The low efficiency of embryo production in Holstein cows during early lactation presents many challenges for animal production. To improve its efficiency, the outcomes of single GnRH injections 48 hours before each of three cycles of ovum pick up (OPU; weeks 2, 4, and 6) were compared with three cycles of unstimulated OPU (controls; weeks 1, 3, and 5) in 35 Holstein cows during 6 weeks of early lactation (40-80 days postpartum). More total follicle numbers (19.5 vs. 16.0; P controls (15.3 vs. 11.5; P controls (2.8 vs. 1.7 and 5.8 vs. 4.2, respectively; P control cycles (13.7 vs. 9.6; P controls (9.0 vs. 6.2 two-cell embryos; 4.7 vs. 3.0 four-cell embryos; 3.3 vs. 2.0 morulae; and 3.0 vs. 1.7 blastocysts, respectively). Moreover, there was no significant difference in pregnancy rate of the recipient cows after embryo transfer (57.1% vs. 42.1%; P > 0.05) no matter if the embryos came from the GnRH-treated cycles or not. Thus, GnRH-stimulated OPUs improved the efficiency of embryo production in Holstein cows during early lactation. This novel method for in vitro embryo production should benefit the dairy industry.

  11. Seasonal differences in the parameters of luteinizing hormone release to exogenous gonadotropin releasing hormone in prepubertal Holstein heifers in Sapporo.

    Science.gov (United States)

    Kadokawa, Hiroya

    2007-02-01

    Stress due to summer heat has adverse effects on reproduction in Holstein dairy cattle. Summer suppression of reproduction of Holsteins can pose an important economic problem, even in Hokkaido prefecture located in the northern region of Japan. Hokkaido is one of the most important dairy farming areas of Japan. This study is an attempt to clarify the seasonal differences in the parameters of luteinizing hormone (LH) response to exogenous gonadotropin releasing hormone (GnRH) in Sapporo, Hokkaido, Japan. A total of 12 prepubertal heifers received an injection with GnRH analogue intramuscularly in either May (n=4, May group), July (n=4, July group), or November (n=4, November group), and serial blood samples were collected to analyze the parameters of the LH response curve after GnRH injection. The parameters were as follows: the basal LH concentration, peak LH concentration, duration from the time of GnRH injection to the time of the peak LH concentration, and area under the LH response curve (AUC). There were no significant differences in the basal and peak LH concentrations or the AUC among the three groups. The July group reached the LH peak significantly (P<0.05) faster than the May group, but there was no significant difference with the November group. Therefore, the results of the present study do not demonstrate an effect of summer heat on the LH response to the exogenous GnRH in Holstein heifers.

  12. Familial idiopathic gonadotropin deficiency not linked to gene for gonadotropin-releasing hormone (GnRH) in Brazilian kindred

    Energy Technology Data Exchange (ETDEWEB)

    Faraco, J.; Francke, U.; Toledo, S. [Stanford Univ. School of Medicine, CA (United States)

    1994-09-01

    Familial idiopathic gonadotropin deficiency (FIGD) is an autosomal recessive disorder which results in failure to develop secondary sexual characteristics. The origin is a hypothalamic defect resulting in insufficient secretion of gonadotropin-releasing hormone GnRH (also called LHRH, luteinizing hormone releasing hormone) and follicle-stimuating hormone (FSH). FIGD has been determined to be a separate entity from Kallmann syndrome which presents with hypogonadism as well as anosmia. The FIGD phenotype appears to be analogous to the phenotype of the hpg (hypogonadal) mouse. Because the hpg phenotype is the result of a structurally abnormal GnRH gene, we have studied the GnRH gene in individuals from a previously reported Brazilian FIGD family. An informative dimorphic marker in the signal peptide sequence of the GnRH gene allowed assessment of linkage between the disease gene and the GnRH locus in this pedigree. We have concluded that the GnRH locus is not linked to the disease-causing mutation in these hypogonadal individuals. Recent evidence suggests that neuropeptide Y (NPY) may play a role in the initiation of puberty. We hypothesize that mutations in NPY may result in failure to secrete GnRH. We have characterized three diallelic frequent-cutter restriction fragment length polymorphisms within the human NPY locus, and are currently using these markers to determine if the NPY gene is linked to, and possibly the site of the disease mutation in this kindred.

  13. Treatment of cryptorchidism with human chorionic gonadotropin or gonadotropin releasing hormone. A double-blind controlled study of 243 boys

    DEFF Research Database (Denmark)

    Christiansen, P; Müller, J; Buhl, S;

    1988-01-01

    We have conducted a modified double-blind study on the effect of human chorionic gonadotropin (hCG), gonadotropin releasing hormone (GnRH) and placebo on bilateral and unilateral maldescended testes. One hundred and fifty-five boys with bilateral and 88 boys with unilateral cryptorchidism fulfilled...... the inclusion criteria and completed the treatment protocol. The boys were between 1 and 13 years of age. hCG was administered as intramuscular injections twice weekly for 3 weeks. GnRH and placebo were given intranasally. hCG was superior to GnRH and placebo in the treatment of bilateral maldescended testes (p......% after placebo and GnRH, respectively (p = 0.07). The testis had moved to a more distal position in 46% of the boys treated with hCG. There was no significant difference between the treatment groups with regard to age or initial position of the testes. We conclude that a success rate of 25% justifies...

  14. Treatment of idiopathic short stature: effects of gonadotropin-releasing hormone analogs, aromatase inhibitors and anabolic steroids.

    Science.gov (United States)

    Dunkel, Leo

    2011-01-01

    Modulation of sex steroid action on the growth plate can, at least theoretically, increase adult height in children and adolescents with idiopathic short stature. Gonadotropin-releasing hormone (GnRH) analog therapy during adolescence has been shown effective in a placebo-controlled study, but to obtain clinically significant increases in adult height, the treatment duration must be lengthy (several years). Furthermore, such treatment seems to compromise bone health and, because of the resulting delay in pubertal development, likely has psychosocial consequences. Therefore, GnRH analogs are no longer recommended to augment height in adolescents with short stature and normally timed puberty. Aromatase inhibitors are probably more effective than GnRH analogs in promoting increased adult height in children with short stature and, unlike GnRH analogs, do not delay pubertal development in males. However, due to a dearth of safety data with aromatase inhibitors for the treatment of short stature, their use outside a research setting is currently not recommended. Positive effects of anabolic steroids on adult height have not been documented.

  15. The role of Serine Proteases and Serine Protease Inhibitors in the migration of Gonadotropin-Releasing Hormone neurons

    Directory of Open Access Journals (Sweden)

    Silverman Ann-Judith

    2002-02-01

    Full Text Available Abstract Background Mechanisms regulating neuronal migration during development remain largely undefined. Extracellular matrix cues, target site released factors, and components of the migratory neurons themselves are likely all coordinated in time and space directing neurons to their appropriate locations. We have studied the effects of proteases and their inhibitors on the extracellular matrix and the consequences to the migration of gonadotropin releasing hormone (GnRH neurons in the embryonic chick. Chick GnRH neurons differentiate in the olfactory epithelium, migrate along the olfactory nerve and enter the forebrain. The accessibility of this coherent cell group make it amenable for studying protease/inhibitor roles in migratory processes. Results Affigel blue beads were used to deliver a serine protease inhibitor, protease nexin-1 (PN-1, and a target protease, trypsin, to the olfactory epithelium coincident with initiation of GnRH neuronal migration. PN-1 inhibited neuronal migration while trypsin accelerated their transit into the CNS. Prior to initiation of migration, neither PN-1 nor trypsin altered the timing of neuronal exit. Trypsin did, however, accelerate the timing of neuronal crossing into the nerve-forebrain junction. Conclusions These data support the hypothesis that protease activity modulates neuronal movements across barriers. Moreover, the data suggest, for the first time, that aspects of GnRH neuronal migration may be cell autonomous but modulated by ECM alterations.

  16. Factors to predict positive results of gonadotropin releasing hormone stimulation test in girls with suspected precocious puberty.

    Science.gov (United States)

    Nam, Hyo-Kyoung; Rhie, Young Jun; Son, Chang Sung; Park, Sang Hee; Lee, Kee-Hyoung

    2012-02-01

    Sometimes, the clinical findings and the results of the gonadotropin-releasing hormone (GnRH) stimulation test are inconsistent in girls with early breast development and bone age advancement. We aimed to investigate the factors predicting positive results of the GnRH stimulation test in girls with suspected central precocious puberty (CPP). We reviewed the records of 574 girls who developed breast budding before the age of 8 yr and underwent the GnRH stimulation test under the age of 9 yr. Positive results of the GnRH stimulated peak luteinizing hormone (LH) level were defined as 5 IU/L and over. Girls with the initial positive results (n = 375) showed accelerated growth, advanced bone age and higher serum basal LH, follicle-stimulating hormone, and estradiol levels, compared to those with the initial negative results (n = 199). Girls with the follow-up positive results (n = 64) showed accelerated growth and advanced bone age, compared to those with the follow-up negative results. In the binary logistic regression, the growth velocity ratio was the most significant predictive factor of positive results. We suggest that the rapid growth velocity is the most useful predictive factor for positive results in the GnRH stimulation test in girls with suspected precocious puberty.

  17. Olfactory ensheathing glia are required for embryonic olfactory axon targeting and the migration of gonadotropin-releasing hormone neurons

    Directory of Open Access Journals (Sweden)

    Perrine Barraud

    2013-06-01

    Kallmann's syndrome is caused by the failure of olfactory axons and gonadotropin-releasing hormone (GnRH neurons to enter the embryonic forebrain, resulting in anosmia and sterility. Sox10 mutations have been associated with Kallmann's syndrome phenotypes, but their effect on olfactory system development is unknown. We recently showed that Sox10 is expressed by neural crest-derived olfactory ensheathing cells (OECs. Here, we demonstrate that in homozygous Sox10lacZ/lacZ mouse embryos, OEC differentiation is disrupted; olfactory axons accumulate in the ventromedial olfactory nerve layer and fewer olfactory receptor neurons express the maturation marker OMP (most likely owing to the failure of axonal targeting. Furthermore, GnRH neurons clump together in the periphery and a smaller proportion enters the forebrain. Our data suggest that human Sox10 mutations cause Kallmann's syndrome by disrupting the differentiation of OECs, which promote embryonic olfactory axon targeting and hence olfactory receptor neuron maturation, and GnRH neuron migration to the forebrain.

  18. Aromatase inhibitors with or without gonadotropin-releasing hormone analogue in metastatic male breast cancer: a case series

    Science.gov (United States)

    Zagouri, F; Sergentanis, T N; Koutoulidis, V; Sparber, C; Steger, G G; Dubsky, P; Zografos, G C; Psaltopoulou, T; Gnant, M; Dimopoulos, M-A; Bartsch, R

    2013-01-01

    Background: Data regarding the safety and effectiveness of aromatase inhibitors (AIs) as monotherapy or combined with gonadotropin-releasing hormone (GnRH) analogue in male breast cancer are scarce. Methods: In this retrospective chart review, cases of male breast cancer patients treated with AIs with or without a GnRH analogue were evaluated. Results: Twenty-three men were included into this case series. Aromatase inhibitors in combination with or without a GnRH analogue were given as first-line therapy in 60.9% and as second-line therapy in 39.1% of patients, respectively. All patients had visceral metastases, whereas in five of them bone lesions coexisted. In all cases AIs were tolerated well, and no case of grade 3 and 4 adverse events was reported. A partial response was observed in 26.1% of patients and stable disease in 56.5%. Median overall survival (OS) was 39 months and median progression-free survival (PFS) was 13 months. Regarding OS and PFS, no significant effects of GnRH analogue co-administration or type of AI were noted. Conclusion: Our study shows that AIs with or without GnRH analogues may represent an effective and safe treatment option for hormone-receptor positive, pretreated, metastatic, male breast cancer patients. PMID:23722469

  19. Body image and depression in girls with idiopathic precocious puberty treated with gonadotropin-releasing hormone analogue

    Science.gov (United States)

    Choi, Min-Seon

    2016-01-01

    Purpose Precocious puberty (PP) is associated with psychological and behavioral problems. This study aimed to evaluate the perception of body image and depression in girls with PP receiving gonadotropin-releasing hormone (GnRH) analogue therapy. Methods From March to August 2013, 82 girls with PP receiving GnRH analogue therapy were enrolled. Height, weight, body mass index, and stages of pubertal development were assessed. Participants completed a series of questionnaires on their body image perception and pubertal self-assessment. The depression score was calculated using the Korean Kovacs' Children's Depression Inventory. Results The patients perceived their body to be more obese than the controls did. The mean depression score did not differ between the patients and controls. The mean depression scores according to Tanner stages (1: prepubertal, 2: early pubertal, and 3–5: mid to late pubertal stage) by self-assessment were 5.2±3.6, 6.8±4.9, and 11.4±10.1 (Pperception of overall body build and figure (%) and the mean depression scores in patients were: dissatisfied (25.6%, 9.7±7.8) and satisfied (74.4%, 5.5±3.4) (Pperception of pubertal status and satisfaction about height or weight are unrelated to objective physical findings. Patients with PP are prone to distorted perception about their body image and breast development. Such incorrect body image seems to contribute to depression score. PMID:27777908

  20. NiH2 Cycle Life Study

    Science.gov (United States)

    Hollandsworth, Roger P.; Armantrout, Jon D.; Rao, Gopalakrishna M.

    2002-01-01

    Cycle life studies have been performed at Eagle Picher Technologies (EPT), on HST Mantech design cells with various pedigrees of slurry and dry sinter processed electrodes, to evaluate peak load voltage performance during generic load profile testing. These tests provide information for determining voltage and capacity fade (degradation) mechanisms, and their impact on nickel hydrogen cell cycle life. Comparison of peak load voltage fade, as a function of State of Charge and cycle life, with capacity data from HST indicates that the cycle life limiting mechanism is due to impedance growth, and formation of a second discharge plateau. With a second plateau on discharge, capacity from the cell is still available, but at an unacceptable low voltage of 0.8 V per cell (17.6 V battery). Data shows that cell impedance increases with cycle number and depth of discharge, as expected.

  1. Changes in gonadotropin-releasing hormone and gonadotropin-releasing hormone receptor gene expression after an increase in carbon monoxide concentration in the cavernous sinus of male wild boar and pig crossbread.

    Science.gov (United States)

    Romerowicz-Misielak, M; Tabecka-Lonczynska, A; Koziol, K; Gilun, P; Stefanczyk-Krzymowska, S; Och, W; Koziorowski, M

    2016-06-01

    Previous studies indicate that there are at least a few regulatory systems involved in photoperiodic synchronisation of reproductive activity, which starts with the retina and ends at the gonadotropin-releasing hormone (GnRH) pulse generator. Recently we have shown indicated that the amount of carbon monoxide (CO) released from the eye into the ophthalmic venous blood depends on the intensity of sunlight. The aim of this study was to test whether changes in the concentration of carbon monoxide in the ophthalmic venous blood may modulate reproductive activity, as measured by changes in GnRH and GnRH receptor gene expression. The animal model used was mature male swine crossbred from wild boars and domestic sows (n = 48). We conducted in vivo experiments to determine the effect of increased CO concentrations in the cavernous sinus of the mammalian perihypophyseal vascular complex on gene expression of GnRH and GnRH receptors as well as serum luteinizing hormone (LH) levels. The experiments were performed during long photoperiod days near the summer solstice (second half of June) and short photoperiod days near the winter solstice (second half of December). These crossbred swine demonstrated a seasonally-dependent marked variation in GnRH and GnRH receptor gene expression and systemic LH levels in response to changes in CO concentration in ophthalmic venous blood. These results seem to confirm the hypothesis of humoral phototransduction as a mechanism for some of bright light's effects in animal chronobiology and the effect of CO on GnRH and GnRH receptor gene expression.

  2. Effects of leptin on gonadotropin-releasing hormone release from hypothalamic-infundibular explants and gonadotropin release from adenohypophyseal primary cell cultures: further evidence that fully nourished cattle are resistant to leptin.

    Science.gov (United States)

    Amstalden, M; Harms, P G; Welsh, T H; Randel, R D; Williams, G L

    2005-01-01

    In rodents and pigs, leptin stimulates the release of gonadotropin-releasing hormone (GnRH) from hypothalamus, gonadotropins from adenohypophyseal (AP) explants and cells, and luteinizing hormone (LH) from full-fed animals. In the current studies, we investigated whether leptin could stimulate the release of GnRH from bovine hypothalamic-infundibular (HYP) explants and gonadotropins from bovine adenohypophyseal cells. In Experiment 1A, HYP explants collected from 17 bulls and seven steers were incubated with Krebs-Ringer bicarbonate buffer (KRB) containing 0, 10, 100, or 1000 ng/ml recombinant ovine leptin (oleptin) for 30 min after a 3-h period of equilibration. None of the doses of leptin affected (P > 0.05) GnRH release into the media. In Experiment 1B, HYP explants collected from six steers were incubated with KRB containing 0 or 1000 ng/ml oleptin for two consecutive 30-min periods and challenged with 60 mM K(+) afterwards. Leptin did not affect (P > 0.05) basal or K(+)-stimulated release of GnRH. In Experiment 2, adenohypophyses from steers were collected at slaughter and cells dispersed and cultured for 4 days. On day 5, cells were treated with media alone (control) or media containing 10(-11), 10(-10), 10(-9), and 10(-8)M oleptin. Three independent replications were performed. None of the doses of leptin stimulated (P > 0.05) the release of LH. Although leptin at 10(-11), 10(-10), and 10(-9)M increased (P release of FSH compared to control-treated cells in one replicate, this effect was not confirmed in the other two replicates. Results support the hypothesis that leptin has limited effects on the release of GnRH and gonadotropins in full-fed cattle and reiterate important species differences in responsiveness to leptin.

  3. Life extension and life cycle management

    Energy Technology Data Exchange (ETDEWEB)

    Hoang, H., E-mail: hoa.hoang@ge.co [GE Hitachi Nuclear Energy, 3901 Castle Hayne Rd., Wilmington, NC 28402 (United States)

    2010-10-15

    To continue the effort of nuclear energy as the clean energy offsetting the increase in greenhouse gas emission that contributes to the increased global warming effect, the nuclear industry is focused on the optimization of their current nuclear generation assets. Plant life extension (Plex) and Plant life management (Plim), together with power up rate, are the key strategies for the optimization effort. Plex begins with the process to obtain the regulatory approval for an additional 20 years of operation, beyond the current 40-year limit. This highly standardized process consists of the following steps: 1) Scoping: identify the systems, structures and components for inclusion in the license renewal scope of work. 2) Screening: narrow down the selection of the in-scope systems, structures and components based on passive and long-lived characteristics. 3) Aging management review: demonstrate that aging effects will continue to be managed during the additional 20 years of operation. 4) Time limiting aging analyses: confirm the acceptability of design bases analyses that assume the 40-year plant life as a key input assumptions. To provide a consistent approach for the preparation of the license renewal application, the following are the key guidance documents: NUREG-1800: Standard review plan; NUREG-1801: Generic aging lessons learned; Nuclear Energy Institute NEI 95-10. The objectives of Plim are to focus on improving plant reliability/availability, and to plan for equipment upgrades for efficiency improvement as well as technological obsolescence. Plim is a technical evaluation combined with a risk assessment to produce a long-range business plant with a time horizon of 10 years or longer. Due to its long view nature, this plan will be reviewed on a yearly basis for any required adjustments. The technical evaluation consists of the following major steps: 1) Select systems, structures and components with performance deficiencies experience. 2) Collect operating data

  4. All about Animal Life Cycles. Animal Life for Children. [Videotape].

    Science.gov (United States)

    2000

    While watching the development from tadpole to frog, caterpillar to butterfly, and pup to wolf, children learn about the life cycles of animals, the different stages of development, and the average life spans of a variety of creatures. This videotape correlates to the following National Science Education Standards for Life Science: characteristics…

  5. Follicular atresia and infertility in rats treated with a gonadotropin-releasing hormone antagonist.

    Science.gov (United States)

    Sharpe, K L; Bertero, M C; Lyon, B P; Muse, K N; Vernon, M W

    1990-07-01

    Adverse effects of the GnRH antagonist Antide on folliculogenesis and fertility were noted when we were evaluating the therapeutic value of Antide on endometriosis in a rat model. Cyclic rats with (n = 56) and without (n = 18) surgically induced endometriosis received Antide (2 mg/kg) or vehicle at noon on days 0 (proestrus), 3, 6, and 9. Rats were killed at noon on days 0, 6, 12, 18, 24, 30, 42, and 165. The number of antral follicles and the number of atretic antral follicles evaluated did not differ (P greater than 0.05) between endometriosis and control rats. Antide-treated rats had more (P less than 0.05 ) atretic antral follicles (64.7%) than vehicle-treated rats (15.3%). Antide-treated rat ovaries contained fewer corpora lutea than those of vehicle-treated rats on days 6, 12, and 18. No corpora lutea were found in Antide-treated rat ovaries after day 18. The abnormal ovarian morphology of the Antide-treated rats persisted for the duration of the project (165 days). Fertility (rats without endometriosis) was assessed by mating vehicle-and Antide-treated rats at spontaneous proestrus (n = 8) for eight posttreatment cycles as well as after follicular stimulation (n = 2). All vehicle-treated and no Antide-treated rats became pregnant. No oocytes were found in the oviducts of Antide-treated rats after eight cycles, indicating that ovulation had not occurred. The serum FSH and estradiol concentrations in the rats treated with Antide were lower (P less than 0.05) on days 6, 12, and 18, but rose to values equal to (days 24 and 30) or greater than (day 42) those in vehicle-treated rats. Serum progesterone levels in rats treated with Antide were lower (P less than 0.05) than those in vehicle-treated rats on all days tested. In conclusion, at a dosage sufficient to suppress reproductive cyclicity (and elicit the regression of endometriosis), Antide also caused long term follicular atresia and infertility.

  6. Life Cycle Assessment of Slurry Management Technologies

    DEFF Research Database (Denmark)

    Wesnæs, Marianne; Wenzel, Henrik; Petersen, Bjørn Molt

    This report contains the results of Life Cycle Assessments of two slurry management technologies - acidification and decentred incineration. The LCA foundation can be used by the contributing companies for evaluating the environmental sustainability of a specific technology from a holistic Life...... Cycle perspective. Through this the companies can evaluate the environmental benefits and disadvantages of introducing a specific technology for slurry management. From a societal perspective the results can contribute to a clarification of which slurry management technologies (or combination...

  7. Trusted Computing Exemplar: Life Cycle Management Plan

    Science.gov (United States)

    2014-12-12

    Informal “An informal specification is written as prose in natural language...(e.g., Dutch, English, French, German). An informal specification is not...informal) prose . The restricted syntax language may be a natural language with restricted sentence structure and keywords with special meaning, or it may...accompanied by supporting explanatory (informal) prose .” [4] TCX: Life Cycle Management Plan NPS-CAG-14-002 4 2 Life Cycle Phases and Activities

  8. Fuel cell hybrid taxi life cycle analysis

    Energy Technology Data Exchange (ETDEWEB)

    Baptista, Patricia, E-mail: patricia.baptista@ist.utl.pt [IDMEC-Instituto Superior Tecnico, Universidade Tecnica de Lisboa, Av. Rovisco Pais, 1, 1049-001 Lisboa (Portugal); Ribau, Joao; Bravo, Joao; Silva, Carla [IDMEC-Instituto Superior Tecnico, Universidade Tecnica de Lisboa, Av. Rovisco Pais, 1, 1049-001 Lisboa (Portugal); Adcock, Paul; Kells, Ashley [Intelligent Energy, Charnwood Building, HolywellPark, Ashby Road, Loughborough, LE11 3GR (United Kingdom)

    2011-09-15

    A small fleet of classic London Taxis (Black cabs) equipped with hydrogen fuel cell power systems is being prepared for demonstration during the 2012 London Olympics. This paper presents a Life Cycle Analysis for these vehicles in terms of energy consumption and CO{sub 2} emissions, focusing on the impacts of alternative vehicle technologies for the Taxi, combining the fuel life cycle (Tank-to-Wheel and Well-to-Tank) and vehicle materials Cradle-to-Grave. An internal combustion engine diesel taxi was used as the reference vehicle for the currently available technology. This is compared to battery and fuel cell vehicle configurations. Accordingly, the following energy pathways are compared: diesel, electricity and hydrogen (derived from natural gas steam reforming). Full Life Cycle Analysis, using the PCO-CENEX drive cycle, (derived from actual London Taxi drive cycles) shows that the fuel cell powered vehicle configurations have lower energy consumption (4.34 MJ/km) and CO{sub 2} emissions (235 g/km) than both the ICE Diesel (9.54 MJ/km and 738 g/km) and the battery electric vehicle (5.81 MJ/km and 269 g/km). - Highlights: > A Life Cycle Analysis of alternative vehicle technologies for the London Taxi was performed. > The hydrogen powered vehicles have the lowest energy consumption and CO{sub 2} emissions results. > A hydrogen powered solution can be a sustainable alternative in a full life cycle framework.

  9. A case study by life cycle assessment

    Science.gov (United States)

    Li, Shuyun

    2017-05-01

    This article aims to assess the potential environmental impact of an electrical grinder during its life cycle. The Life Cycle Inventory Analysis was conducted based on the Simplified Life Cycle Assessment (SLCA) Drivers that calculated from the Valuation of Social Cost and Simplified Life Cycle Assessment Model (VSSM). The detailed results for LCI can be found under Appendix II. The Life Cycle Impact Assessment was performed based on Eco-indicator 99 method. The analysis results indicated that the major contributor to the environmental impact as it accounts for over 60% overall SLCA output. In which, 60% of the emission resulted from the logistic required for the maintenance activities. This was measured by conducting the hotspot analysis. After performing sensitivity analysis, it is evidenced that changing fuel type results in significant decrease environmental footprint. The environmental benefit can also be seen from the negative output values of the recycling activities. By conducting Life Cycle Assessment analysis, the potential environmental impact of the electrical grinder was investigated.

  10. A Novel Gonadotropin-Releasing Hormone 1 (Gnrh1 Enhancer-Derived Noncoding RNA Regulates Gnrh1 Gene Expression in GnRH Neuronal Cell Models.

    Directory of Open Access Journals (Sweden)

    Polly P Huang

    Full Text Available Gonadotropin-releasing hormone (GnRH, a neuropeptide released from a small population of neurons in the hypothalamus, is the central mediator of the hypothalamic-pituitary-gonadal axis, and is required for normal reproductive development and function. Evolutionarily conserved regulatory elements in the mouse, rat, and human Gnrh1 gene include three enhancers and the proximal promoter, which confer Gnrh1 gene expression specifically in GnRH neurons. In immortalized mouse hypothalamic GnRH (GT1-7 neurons, which show pulsatile GnRH release in culture, RNA sequencing and RT-qPCR revealed that expression of a novel long noncoding RNA at Gnrh1 enhancer 1 correlates with high levels of GnRH mRNA expression. In GT1-7 neurons, which contain a transgene carrying 3 kb of the rat Gnrh1 regulatory region, both the mouse and rat Gnrh1 enhancer-derived noncoding RNAs (GnRH-E1 RNAs are expressed. We investigated the characteristics and function of the endogenous mouse GnRH-E1 RNA. Strand-specific RT-PCR analysis of GnRH-E1 RNA in GT1-7 cells revealed GnRH-E1 RNAs that are transcribed in the sense and antisense directions from distinct 5' start sites, are 3' polyadenylated, and are over 2 kb in length. These RNAs are localized in the nucleus and have a half-life of over 8 hours. In GT1-7 neurons, siRNA knockdown of mouse GnRH-E1 RNA resulted in a significant decrease in the expression of the Gnrh1 primary transcript and Gnrh1 mRNA. Over-expression of either the sense or antisense mouse GnRH-E1 RNA in immature, migratory GnRH (GN11 neurons, which do not express either GnRH-E1 RNA or GnRH mRNA, induced the transcriptional activity of co-transfected rat Gnrh1 gene regulatory elements, where the induction requires the presence of the rat Gnrh1 promoter. Together, these data indicate that GnRH-E1 RNA is an inducer of Gnrh1 gene expression. GnRH-E1 RNA may play an important role in the development and maturation of GnRH neurons.

  11. Maternal behavior in transgenic mice with reduced fibroblast growth factor receptor function in gonadotropin-releasing hormone neurons

    Directory of Open Access Journals (Sweden)

    Brooks Leah R

    2012-09-01

    Full Text Available Abstract Background Fibroblast growth factors (FGFs and their receptors (FGFRs are necessary for the proper development of gonadotropin-releasing hormone (GnRH neurons, which are key activators of the hypothalamo-pituitary-gonadal axis. Transgenic mice that have the targeted expression of a dominant negative FGFR (dnFGFR in GnRH neurons (dnFGFR mice have a 30% decrease of GnRH neurons. Additionally, only 30–40% of the pups born to the transgenic dams survive to weaning age. These data raised the possibility that FGFR defects in GnRH neurons could adversely affect maternal behavior via novel mechanisms. Methods We first determined if defective maternal behavior in dnFGFR mothers may contribute to poor pup survival by measuring pup retrieval and a battery of maternal behaviors in primiparous control (n = 10–12 and dnFGFR (n = 13–14 mothers. Other endocrine correlates of maternal behaviors, including plasma estradiol levels and hypothalamic pro-oxyphysin and GnRH transcript levels were also determined using enzyme-linked immunoassay and quantitative reverse transcription polymerase chain reaction, respectively. Results Maternal behaviors (% time crouching with pups, time off pups but not feeding, time feeding, and total number of nesting bouts were not significantly different in dnFGFR mice. However, dnFGFR dams were more likely to leave their pups scattered and took significantly longer to retrieve each pup compared to control dams. Further, dnFGFR mothers had significantly lower GnRH transcripts and circulating E2, but normal pro-oxyphysin transcript levels. Conclusions Overall, this study suggests a complex scenario in which a GnRH system compromised by reduced FGF signaling leads to not only suboptimal reproductive physiology, but also suboptimal maternal behavior.

  12. Predicting the effect of gonadotropin-releasing hormone (GnRH) analogue treatment on uterine leiomyomas based on MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Matsuno, Y.; Yamashita, Y.; Takahashi, M. [Dept. of Radiology, Kumamoto Univ. School of Medicine, Kumamoto (Japan); Katabuchi, H.; Okamura, H. [Dept. of Gynecology and Obstetrics, Kumamoto Univ. School of Medicine, Kumamoto (Japan); Kitano, Y.; Shimamura, T. [Dept. of Gynecology and Obstetrics, Amakusa Chuou General Hospital, Hondo (Japan)

    1999-11-01

    Purpose: To test the hypothesis that the simple assessment of signal intensity on T2-weighted MR images is predictive of the effect of hormonal treatment with gonadotropin-releasing hormone (GnRH) analogue. Material and methods: The correlation between T2-weighted MR imaging of uterine leiomyomas and histologic findings was evaluated using 85 leiomyomas from 62 females who underwent myomectomy or hysterectomy. We also correlated the pretreatment MR images features obtained in 110 women with 143 leiomyomas with the effect of GnRH analogue treatment. The size (length x width x depth) of the leiomyoma was evaluated before and at 6 months after treatment by ultrasound. Results: The proportion of leiomyoma cell fascicles and that of extracellular matrix affected signal intensities of uterine leiomyomas on T2-weighted MR images. The amount of extracellular matrix was predominant in hypointense leiomyomas on T2-weighted images, while diffuse intermediate signal leiomyomas were predominantly composed of leiomyoma cell fascicles. Marked degenerative changes were noted in leiomyomas with heterogenous hyperintensity. The homogeneously intermediate signal intensity leiomyomas showed significant size reduction after treatment (size ratio; posttreatment volume/pretreatment volume 0.29{+-}0.11). The size ratio for the hypointense tumors was 0.82{+-}0.14, and 0.82{+-}0.18 for the heterogeneously hyperintense tumors. There was a significant difference in the response to treatment between the homogeneously intermediate signal intensity leiomyomas and the hypointense or heterogeneously hyperintense leiomyomas (both p<0.01). Conclusion: Signal intensity on T2-weighted MR images depends on the amount of leiomyoma cell fascicles and extracellular matrix. Simple assessment of the MR signal intensity is useful in predicting the effect of GnRH analogue on uterine leiomyomas. (orig.)

  13. Predictive Value of Dental Maturity for a Positive Gonadotropin-Releasing Hormone Stimulation Test Result in Girls with Precocious Puberty

    Science.gov (United States)

    2017-01-01

    Dental maturity is associated with skeletal maturity, which is advanced in girls with central precocious puberty (CPP). We investigated the performance of dental maturity as a screening method for CPP using mandibular second premolar and molar calcification stages, assessed the associated anthropometric and laboratory factors, and evaluated pubertal response predictors using the gonadotropin-releasing hormone stimulation test (GnRHST) in prepubertal and pubertal girls. A prospective case-control study was conducted in girls, aged 7.0–8.9 years, classified into pubertal (peak luteinizing hormone [LH] after GnRHST ≥ 5 IU/L), prepubertal (peak LH < 5 IU/L), and control groups. Auxological and biochemical tests, panoramic radiographs, and GnRHSTs in participants with breast development were conducted. Dental maturity was assessed using the Demirjian index (DI). We included 103 girls (pubertal, 40; prepubertal, 19; control, 44). Chronological age (CA) was not significantly different between groups. Bone age (BA) and BA advancement was higher in the pubertal and prepubertal groups. Increased DI values at the mandibular second premolar and molar were significantly associated with CA, BA, BA advancement, height standard deviation score (SDS), peak LH after GnRHST, and insulin-like growth factor-I (IGF-I) (all P < 0.05). Moreover, odds ratio (OR) of the mandibular second premolar and molar (a DI value of ≥ E) for predicting a positive response to GnRHST was 8.7 (95% confidence intervals [CI], 2.9–26.1) and 5.2 (95% CI, 2.2–12.7), respectively. Dental maturity was a strong predictor for diagnosing CPP. Determining dental maturity in girls with suspected precocious puberty might help determine the performance of GnRHSTs. PMID:28049241

  14. Effects of a gonadotropin-releasing hormone antagonist on gonadotropin levels in Masu salmon and Sockeye salmon.

    Science.gov (United States)

    Amano, Masafumi; Ikuta, Kazumasa; Kitamura, Shoji

    2007-09-01

    The salmon gonadotropin-releasing hormone (sGnRH) is considered to be involved in gonadal maturation via gonadotropin (GTH) secretion in salmonid fishes. However, there is no direct evidence for endogenous sGnRH-stimulated GTH secretion in salmonids. In this study, to clarify whether endogenous sGnRH stimulates GTH secretion, we examined the effects of the mammalian GnRH (mGnRH) antagonist [Ac-Delta(3)-Pro(1), 4FD-Phe(2), D-Trp(3,6)]-mGnRH on luteinizing hormone (LH) levels in 0-year-old masu salmon Oncorhynchus masou and sockeye salmon Oncorhynchus nerka. First, the effects of the GnRH antagonist on LH release were examined in 0-year-old precocious male masu salmon. GnRH antagonist treatment for 3 hr significantly inhibited an increase in plasma LH levels that was artificially induced by exogenous sGnRH administration, indicating that the GnRH antagonist is effective in inhibiting LH release from the pituitary. Subsequently, we examined the effect of the GnRH antagonist on LH synthesis in 0-year-old immature sockeye salmon that were pretreated with exogenous testosterone for 42 days to increase the pituitary LH contents; the testosterone treatment did not affect the plasma LH levels. GnRH antagonist treatment slightly but significantly inhibited an increase in the testosterone-stimulated pituitary LH content levels. However, no significant differences in the plasma LH levels were observed between the GnRH antagonist-treated and control groups. These results suggest that endogenous sGnRH is involved in LH secretion in salmonid fishes.

  15. Luteinizing Hormone Secretion during Gonadotropin-Releasing Hormone Stimulation Tests in Obese Girls with Central Precocious Puberty

    Science.gov (United States)

    Lee, Hae Sang; Yoon, Jong Seo; Hwang, Jin Soon

    2016-01-01

    Objective: Girls with precocious puberty have high luteinizing hormone (LH) levels and advanced bone age. Obese children enter puberty at earlier ages than do non-obese children. We analyzed the effects of obesity on LH secretion during gonadotropin-releasing hormone (GnRH) tests in girls with precocious puberty. Methods: A total of 981 subjects with idiopathic precocious puberty who had undergone a GnRH stimulation testing between 2008 and 2014 were included in the study. Subjects were divided into three groups based on body mass index (BMI). Auxological data and gonadotropin levels after the GnRH stimulation test were compared. Results: In Tanner stage 2 girls, peak stimulated LH levels on GnRH test were 11.9±7.5, 10.4±6.4, and 9.1±6.1 IU/L among normal-weight, overweight, and obese subjects, respectively (p=0.035 for all comparisons). In Tanner stage 3 girls, peak stimulated LH levels were 14.9±10.9, 12.8±7.9, and 9.6±6.0 IU/L, respectively (p=0.022 for all comparisons). However, in Tanner stage 4 girls, peak stimulated LH levels were not significantly different among normal, overweight, and obese children. On multivariate analysis, BMI standard deviation score was significantly and negatively associated with peak LH (β=-1.178, p=0.001). Conclusion: In girls with central precocious puberty, increased BMI was associated with slightly lower peak stimulated LH levels at early pubertal stages (Tanner stages 2 and 3). This association was not valid in Tanner stage 4 girls. PMID:27215137

  16. Gonadotropin-releasing hormone positively regulates steroidogenesis via extracellular signal-regulated kinase in rat Leydig cells

    Institute of Scientific and Technical Information of China (English)

    Bing Yao; Hai-Yan Liu; Yu-Chun Gu; Shan-Shan Shi; Xiao-Qian Tao; Xiao-Jun Li; Yi-Feng Ge; Ying-Xia Cui; Guo-Bin Yang

    2011-01-01

    Gonadotropin-releasing hormone (GnRH) is secreted from neurons within the hypothalamus and is necessary for reproductive function in all vertebrates. GnRH is also found in organs outside of the brain and plays an important role in Leydig cell steroidogenesis in the testis. However, the signalling pathways mediating this function remain largely unknown. In this study, we investigated whether components of the mitogen-activated protein kinase (MAPK) pathways are involved in GnRH agonist (GnRHa)-induced testis steroidogenesis in rat Leydig cells. Primary cultures of rat Leydig cells were established. The expression of 3β-hydroxysteroid dehydrogenase (3β-HSD) and the production of testosterone in response to GnRHa were examined at different doses and for different durations by RT-PCR, Western blot analysis and radioimmunoassay (RIA). The effects of GnRHa on ERK1/2, JNK and p38 kinase activation were also investigated in the presence or absence of the MAPK inhibitor PD-98059 by Western blot analysis. GnRHa induced testosterone production and upregulated 3β-HSD expression at both the mRNA and protein levels; it also activated ERK1/2, but not JNK and p38 kinase. Although the maximum effects of GnRHa were observed at a concentration of 100 nmnol L-1 after 24 h, activation of ERK1/2 by GnRHa reached peak at 5 min and it returned to the basal level within 60 min. PD-98059 completely blocked the activation of ERK1/2, the upregulation of 3β-HSD and testosterone production. Our data show that GnRH positively regulates steroidogenesis via ERK signalling in rat Leydig cells. ERK1/2 activation by GnRH may be responsible for the induction of 3β-HSDgene expression and enzyme production, which may ultimately modulate steroidogenesis in rat Leydig cells.

  17. Maternal Dexamethasone Exposure Alters Synaptic Inputs to Gonadotropin-Releasing Hormone Neurons in the Early Postnatal Rat

    Directory of Open Access Journals (Sweden)

    Wei Ling Lim

    2016-08-01

    Full Text Available Maternal dexamethasone (DEX; a glucocorticoid receptor agonist exposure delays pubertal onset and alters reproductive behaviour in the adult offspring. However, little is known whether maternal DEX exposure affects the offspring’s reproductive function by disrupting the gonadotropin-releasing hormone (GnRH neuronal function in the brain. Therefore, this study determined the exposure of maternal DEX on the GnRH neuronal spine development and synaptic cluster inputs to GnRH neurons using transgenic rats expressing enhanced green fluorescent protein (EGFP under the control of GnRH promoter. Pregnant females were administered with DEX (0.1mg/kg or vehicle (VEH, water daily during gestation day 13-20. Confocal imaging was used to examine the spine density of EGFP-GnRH neurons by three-dimensional rendering and synaptic cluster inputs to EGFP-GnRH neurons by synapsin I immunohistochemistry on postnatal day 0 (P0 males. The spine morphology and number on GnRH neurons did not change between the P0 males following maternal DEX and VEH treatment. The number of synaptic clusters within the organum vasculosum of the lamina terminalis (OVLT was decreased by maternal DEX exposure in P0 males. Furthermore, the number and levels of synaptic cluster inputs in close apposition with GnRH neurons was decreased following maternal DEX exposure in the OVLT region of P0 males. In addition, the post synaptic marker molecule, post-synaptic density 95 was observed in GnRH neurons following both DEX and VEH treatment. These results suggest that maternal DEX exposure alters neural afferent inputs to GnRH neurons during early postnatal stage, which could lead to reproductive dysfunction during adulthood.

  18. Histone deacetylases regulate gonadotropin-releasing hormone I gene expression via modulating Otx2-driven transcriptional activity.

    Directory of Open Access Journals (Sweden)

    Lu Gan

    Full Text Available BACKGROUND: Precise coordination of the hypothalamic-pituitary-gonadal axis orchestrates the normal reproductive function. As a central regulator, the appropriate synthesis and secretion of gonadotropin-releasing hormone I (GnRH-I from the hypothalamus is essential for the coordination. Recently, emerging evidence indicates that histone deacetylases (HDACs play an important role in maintaining normal reproductive function. In this study, we identify the potential effects of HDACs on Gnrh1 gene transcription. METHODOLOGY/PRINCIPAL FINDINGS: Inhibition of HDACs activities by trichostatin A (TSA and valproic acid (VPA promptly and dramatically repressed transcription of Gnrh1 gene in the mouse immortalized mature GnRH neuronal cells GT1-7. The suppression was connected with a specific region of Gnrh1 gene promoter, which contains two consensus Otx2 binding sites. Otx2 has been known to activate the basal and also enhancer-driven transcription of Gnrh1 gene. The transcriptional activity of Otx2 is negatively modulated by Grg4, a member of the Groucho-related-gene (Grg family. In the present study, the expression of Otx2 was downregulated by TSA and VPA in GT1-7 cells, accompanied with the opposite changes of Grg4 expression. Chromatin immunoprecipitation and electrophoretic mobility shift assays demonstrated that the DNA-binding activity of Otx2 to Gnrh1 gene was suppressed by TSA and VPA. Overexpression of Otx2 partly abolished the TSA- and VPA-induced downregulation of Gnrh1 gene expression. CONCLUSIONS/SIGNIFICANCE: Our data indicate that HDAC inhibitors downregulate Gnrh1 gene expression via repressing Otx2-driven transcriptional activity. This study should provide an insight for our understanding on the effects of HDACs in the reproductive system and suggests that HDACs could be potential novel targets for the therapy of GnRH-related diseases.

  19. In vitro fertility rate of 129 strain is improved by buserelin (gonadotropin-releasing hormone) administration prior to superovulation.

    Science.gov (United States)

    Vasudevan, K; Sztein, J M

    2012-10-01

    The 129 mice are well recognized for their low fertility and it is speculated that this lack of fertility may be due to the oocyte condition. In this study we investigated superovulation regimens for the 129S1/SvImJ mouse strain to improve the oocyte quality and fertility rate of in vitro fertilization (IVF). Female mice were divided into four groups based on hormone and timing of injection. Group 1 received pregnant mare serum gonadotropin (PMSG) and 48 h later human chorionic gonadotropin (hCG); using the same dose, group 2 received hCG 52 h post-PMSG and group 3, 55 h post-PMSG. Group 4 received buserelin (gonadotropin-releasing hormone agonist [GnRH]) followed 24 h later by PMSG and then hCG 55 h post-PMSG. IVF was performed using 129S1/SvImJ oocytes and sperm; C57BL/6J sperm with 129S1/SvImJ oocytes was used as fertility control. The IVF fertility rate was 1% (Groups 1 and 2), 17% (Group 3) and 55% (Group 4) for 129 oocytes fertilized with 129 sperm. For 129 oocytes fertilized with C57BL/6J sperm, the fertility rate was 5% (Group 1), 10% (Group 2), 40% (Group 3) and 59% (Group 4). These results suggest that extending the interval time between PMSG and hCG and giving GnRH in addition to the standard PMSG and hCG treatments can improve IVF fertility rate of 129S1/SvImJ mouse strains significantly.

  20. Seasonal variation in the gonadotropin-releasing hormone response to kisspeptin in sheep: possible kisspeptin regulation of the kisspeptin receptor.

    Science.gov (United States)

    Li, Qun; Roa, Alexandra; Clarke, Iain J; Smith, Jeremy T

    2012-01-01

    Kisspeptin signaling in the hypothalamus appears critical for the onset of puberty and driving the reproductive axis. In sheep, reproduction is seasonal, being activated by short days and inhibited by long days. During the non-breeding (anestrous) season, gonadotropin-releasing hormone (GnRH) and gonadotropin secretion is reduced, as is the expression of Kiss1 mRNA in the brain. Conversely, the luteinizing hormone response to kisspeptin during this time is greater. To determine whether the GnRH response to kisspeptin is increased during anestrus, we utilized hypophysial portal blood sampling. In anestrus ewes, the GnRH and LH responses to kisspeptin were greater compared to the breeding season (luteal phase). To ascertain whether this difference reflects a change in Kiss1r, we measured its expression on GnRH neurons using in situ hybridization. The level of Kiss1r was greater during the non-breeding season compared to the breeding season. To further examine the mechanism underlying this change in Kiss1r, we examined Kiss1r/GnRH expression in ovariectomized ewes (controlling for sex steroids) during the breeding and non-breeding seasons, and also ovariectomized non-breeding season ewes with or without estradiol replacement. In both experiments, Kiss1r expression on GnRH neurons was unchanged. Finally, we examined the effect of kisspeptin treatment on Kiss1r. Kiss1r expression on GnRH neurons was reduced by kisspeptin infusion. These studies indicate the kisspeptin response is indeed greater during the non-breeding season and this may be due in part to increased Kiss1r expression on GnRH neurons. We also show that kisspeptin may regulate the expression of its own receptor.

  1. Brain morphology and immunohistochemical localization of the gonadotropin-releasing hormone in the bluefin tuna, Thunnus thynnus

    Directory of Open Access Journals (Sweden)

    G Palmieri

    2009-08-01

    Full Text Available The present study was focused on the morphology of the diencephalic nuclei (likely involved in reproductive functions as well as on the distribution of GnRH (gonadotropin-releasing hormone in the rhinencephalon, telencephalon and the diencephalon of the brain of bluefin tuna (Thunnus thynnus by means of immunohistochemistry. Bluefin tuna has an encephalization quotient (QE similar to that of other large pelagic fish. Its brain exhibits well-developed optic tecta and corpus cerebelli. The diencephalic neuron cell bodies involved in reproductive functions are grouped in two main nuclei: the nucleus preopticus-periventricularis and the nucleus lateralis tuberis. The nucleus preopticus-periventricularis consists of the nucleus periventricularis and the nucleus preopticus consisting of a few sparse multipolar neurons in the rostral part and numerous cells closely packed and arranged in several layers in its aboral part. The nucleus lateralis tuberis is located in the ventral-lateral area of the diencephalon and is made up of a number of large multipolar neurones. Four different polyclonal primary antibodies against salmon (sGnRH, chicken (cGnRH-II (cGnRH-II 675, cGnRH-II 6 and sea bream (sbGnRH were employed in the immunohistochemical experiments. No immunoreactive structures were found with anti sbGnRH serum. sGnRH and cGnRH-II antisera revealed immunoreactivity in the perikarya of the olfactory bulbs, preopticus-periventricular nucleus, oculomotor nucleus and midbrain tegmentum. The nucleus lateralis tuberis showed immunostaining only with anti-sGnRH serum. Nerve fibres immunoreactive to cGnRH and sGnRH sera were found in the olfactory bulbs, olfactory nerve and neurohypophysis. The significance of the distribution of the GnRHimmunoreactive neuronal structures is discussed.

  2. Gradual reduction of testosterone using a gonadotropin-releasing hormone vaccination delays castration resistance in a prostate cancer model

    Science.gov (United States)

    Barranco, Jesús A. Junco; Millar, Robert P.; Fuentes, Franklin; Bover, Eddy; Pimentel, Eulogio; Basulto, Roberto; Calzada, Lesvia; Morán, Rolando; Rodríguez, Ayni; Garay, Hilda; Reyes, Osvaldo; Castro, Maria D.; Bringas, Ricardo; Arteaga, Niurka; Toudurí, Henio; Rabassa, Mauricio; Fernández, Yairis; Serradelo, Andrés; Hernández, Eduardo; Guillén, Gerardo E.

    2016-01-01

    In a previous study aimed to design a novel prostate cancer vaccine, the authors of the present study demonstrated the advantage of combining the adjuvants Montanide ISA 51 with very small size proteoliposomes (VSSP) to promote a significant humoral immune response to gonadotropin-releasing hormone (GnRH) in healthy animals. The present study compared the efficacy of this vaccine formulation versus the standard treatment currently available in terms of preventing the development of tumors in DD/S mice injected with Shionogi carcinoma (SC) 115 cells. The results demonstrated that 5 non-vaccinated control mice exhibited a fast tumor growth, and succumbed to the disease within 19–31 days. Mice immunized with the GnRH/Montanide ISA 51/VSSP vaccine exhibited a moderate decline in testosterone levels that was associated with a decrease in anti-GnRH antibody titers, which lead to a sustained tumor growth inhibition. In total, 2 mice in the immunized group exhibited complete remission of the tumor for the duration of the present study. In addition, castrated mice, which were used as a control for standard hormonal therapy, exhibited an accelerated decrease in tumor size. However, tumor relapse was observed between days 50 and 54, and between days 65 and 85, following the injection of SC 155 cells. Therefore, these mice were sacrificed at day 90. The present study concludes that the slow and moderate reduction of testosterone levels observed using the GnRH-based vaccine may delay the appearance of castration resistance in a Shionogi prostate cancer model. These findings suggest that this vaccine may be used to delay castration resistance in patients with prostate cancer. PMID:27446378

  3. Functional Authentication of a Novel Gastropod Gonadotropin-Releasing Hormone Receptor Reveals Unusual Features and Evolutionary Insight

    Science.gov (United States)

    Kavanaugh, Scott I.

    2016-01-01

    A gonadotropin-releasing hormone (GnRH)-like molecule was previously identified in a gastropod, Aplysia californica, and named ap-GnRH. In this study, we cloned the full-length cDNA of a putative ap-GnRH receptor (ap-GnRHR) and functionally authenticated this receptor as a bona fide ap-GnRHR. This receptor contains two potential translation start sites, each accompanied by a Kozak sequence, suggesting the translation of a long and a short form of the receptor is possible. The putative ap-GnRHR maintains the conserved structural motifs of GnRHR-like receptors and shares 45% sequence identity with the octopus GnRHR. The expression of the putative ap-GnRHR short form is ubiquitous in all tissues examined, whereas the long form is only expressed in parts of the central nervous system, osphradium, small hermaphroditic duct, and ovotestis. The cDNA encoding the long or the short receptor was transfected into the Drosophila S2 cell line and subject to a radioreceptor assay using 125I-labeled ap-GnRH as the radioligand. Further, the transfected cells were treated with various concentrations of ap-GnRH and measured for the accumulation of cAMP and inositol monophosphate (IP1). Radioreceptor assay revealed that only the long receptor bound specifically to the radioligand. Further, only the long receptor responded to ap-GnRH with an increased accumulation of IP1, but not cAMP. Our studies show that despite the more prevalent expression of the short receptor, only the long receptor is the functional ap-GnRHR. Importantly, this is only the second report on the authentication of a protostome GnRHR, and based on the function and the phylogenetic grouping of ap-GnRHR, we suggest that this receptor is more similar to protostome corazonin receptors than chordate GnRHRs. PMID:27467252

  4. Functional Authentication of a Novel Gastropod Gonadotropin-Releasing Hormone Receptor Reveals Unusual Features and Evolutionary Insight.

    Science.gov (United States)

    Kavanaugh, Scott I; Tsai, Pei-San

    2016-01-01

    A gonadotropin-releasing hormone (GnRH)-like molecule was previously identified in a gastropod, Aplysia californica, and named ap-GnRH. In this study, we cloned the full-length cDNA of a putative ap-GnRH receptor (ap-GnRHR) and functionally authenticated this receptor as a bona fide ap-GnRHR. This receptor contains two potential translation start sites, each accompanied by a Kozak sequence, suggesting the translation of a long and a short form of the receptor is possible. The putative ap-GnRHR maintains the conserved structural motifs of GnRHR-like receptors and shares 45% sequence identity with the octopus GnRHR. The expression of the putative ap-GnRHR short form is ubiquitous in all tissues examined, whereas the long form is only expressed in parts of the central nervous system, osphradium, small hermaphroditic duct, and ovotestis. The cDNA encoding the long or the short receptor was transfected into the Drosophila S2 cell line and subject to a radioreceptor assay using 125I-labeled ap-GnRH as the radioligand. Further, the transfected cells were treated with various concentrations of ap-GnRH and measured for the accumulation of cAMP and inositol monophosphate (IP1). Radioreceptor assay revealed that only the long receptor bound specifically to the radioligand. Further, only the long receptor responded to ap-GnRH with an increased accumulation of IP1, but not cAMP. Our studies show that despite the more prevalent expression of the short receptor, only the long receptor is the functional ap-GnRHR. Importantly, this is only the second report on the authentication of a protostome GnRHR, and based on the function and the phylogenetic grouping of ap-GnRHR, we suggest that this receptor is more similar to protostome corazonin receptors than chordate GnRHRs.

  5. Gonadotropin-releasing hormone (GnRH) variants in a lizard brain: is mammalian GnRH being expressed?

    Science.gov (United States)

    Montaner, A D; Gonzalez, O; Paz, D A; Affanni, J M; Somoza, G M

    2000-08-01

    In reptiles as in other vertebrates, multiple forms of gonadotropin-releasing hormone (GnRH) within a single brain have been identified. In this group the following GnRH molecular variants have been characterized either by direct or indirect methods: chicken GnRH I (cGnRH-I), chicken GnRH II (cGnRH-II), salmon GnRH (sGnRH) and several unidentified GnRH-like forms. In the present study GnRH variants were investigated in brain extracts of the lizard Tupinambis teguixin (= T. merinae) by combining high-performance liquid chromatography (RP-HPLC) followed by radioimmunoassays (RIA). Two peaks showing GnRH immunoreactivity with the elution position of synthetic mammalian GnRH (mGnRH) and cGnRH-II were detected. Both peaks were further analyzed with different radioimmunoassay systems specific for mGnRH, cGnRH-I, and cGnRH-II. Pooled fractions corresponding to the first eluting peak showed no crossreactivity when analyzed with a cGnRH-I specific assay and logit-log displacement curves were not significantly different from those of synthetic mGnRH with homologous RIA systems. The second peak showed immunological characteristics of cGnRH-II when analyzed with a specific antiserum. The first ir-GnRH peak was selected for further RP-HPLC purification showing similar chromatographic behavior as mGnRH synthetic standard. We demonstrated the absence of cGnRH-I in this lizard using well-characterized antisera.

  6. The human gonadotropin releasing hormone type I receptor is a functional intracellular GPCR expressed on the nuclear membrane.

    Directory of Open Access Journals (Sweden)

    Michelle Re

    Full Text Available The mammalian type I gonadotropin releasing hormone receptor (GnRH-R is a structurally unique G protein-coupled receptor (GPCR that lacks cytoplasmic tail sequences and displays inefficient plasma membrane expression (PME. Compared to its murine counterparts, the primate type I receptor is inefficiently folded and retained in the endoplasmic reticulum (ER leading to a further reduction in PME. The decrease in PME and concomitant increase in intracellular localization of the mammalian GnRH-RI led us to characterize the spatial distribution of the human and mouse GnRH receptors in two human cell lines, HEK 293 and HTR-8/SVneo. In both human cell lines we found the receptors were expressed in the cytoplasm and were associated with the ER and nuclear membrane. A molecular analysis of the receptor protein sequence led us to identify a putative monopartite nuclear localization sequence (NLS in the first intracellular loop of GnRH-RI. Surprisingly, however, neither the deletion of the NLS nor the addition of the Xenopus GnRH-R cytoplasmic tail sequences to the human receptor altered its spatial distribution. Finally, we demonstrate that GnRH treatment of nuclei isolated from HEK 293 cells expressing exogenous GnRH-RI triggers a significant increase in the acetylation and phosphorylation of histone H3, thereby revealing that the nuclear-localized receptor is functional. Based on our findings, we conclude that the mammalian GnRH-RI is an intracellular GPCR that is expressed on the nuclear membrane. This major and novel discovery causes us to reassess the signaling potential of this physiologically and clinically important receptor.

  7. Risk of cardiovascular thrombotic events after surgical castration versus gonadotropin-releasing hormone agonists in Chinese men with prostate cancer

    Directory of Open Access Journals (Sweden)

    Jeremy YC Teoh

    2015-06-01

    Full Text Available We investigated the cardiovascular thrombotic risk after surgical castration (SC versus gonadotropin-releasing hormone agonists (GnRHa in Chinese men with prostate cancer. All Chinese prostate cancer patients who were treated with SC or GnRHa from year 2000 to 2009 were reviewed and compared. The primary outcome was any new-onset of cardiovascular thrombotic events after SC or GnRHa, which was defined as any event of acute myocardial infarction or ischemic stroke. The risk of new-onset cardiovascular thrombotic event was compared between the SC group and the GnRHa group using Kaplan-Meier method. Multivariate Cox regression analysis was performed to adjust for other potential confounding factors. A total of 684 Chinese patients was included in our study, including 387 patients in the SC group and 297 patients in the GnRHa group. The mean age in the SC group (75.3 ± 7.5 years was significantly higher than the GnRHa group (71.8 ± 8.3 years (P < 0.001. There was increased risk of new cardiovascular thrombotic events in the SC group when compared to the GnRHa group upon Kaplan-Meier analysis (P = 0.014. Upon multivariate Cox regression analysis, age (hazard ratio [HR] 1.072, 95% confidence interval [CI] 1.04-1.11, P< 0.001, hyperlipidemia (HR 2.455, 95% CI 1.53-3.93, P< 0.001, and SC (HR 1.648, 95% CI 1.05-2.59, P= 0.031 were significant risk factors of cardiovascular thrombotic events. In conclusion, SC was associated with increased risk of cardiovascular thrombotic events when compared to GnRHa. This is an important aspect to consider while deciding on the method of androgen deprivation therapy, especially in elderly men with known history of hyperlipidemia.

  8. The human gonadotropin releasing hormone type I receptor is a functional intracellular GPCR expressed on the nuclear membrane.

    Science.gov (United States)

    Re, Michelle; Pampillo, Macarena; Savard, Martin; Dubuc, Céléna; McArdle, Craig A; Millar, Robert P; Conn, P Michael; Gobeil, Fernand; Bhattacharya, Moshmi; Babwah, Andy V

    2010-07-08

    The mammalian type I gonadotropin releasing hormone receptor (GnRH-R) is a structurally unique G protein-coupled receptor (GPCR) that lacks cytoplasmic tail sequences and displays inefficient plasma membrane expression (PME). Compared to its murine counterparts, the primate type I receptor is inefficiently folded and retained in the endoplasmic reticulum (ER) leading to a further reduction in PME. The decrease in PME and concomitant increase in intracellular localization of the mammalian GnRH-RI led us to characterize the spatial distribution of the human and mouse GnRH receptors in two human cell lines, HEK 293 and HTR-8/SVneo. In both human cell lines we found the receptors were expressed in the cytoplasm and were associated with the ER and nuclear membrane. A molecular analysis of the receptor protein sequence led us to identify a putative monopartite nuclear localization sequence (NLS) in the first intracellular loop of GnRH-RI. Surprisingly, however, neither the deletion of the NLS nor the addition of the Xenopus GnRH-R cytoplasmic tail sequences to the human receptor altered its spatial distribution. Finally, we demonstrate that GnRH treatment of nuclei isolated from HEK 293 cells expressing exogenous GnRH-RI triggers a significant increase in the acetylation and phosphorylation of histone H3, thereby revealing that the nuclear-localized receptor is functional. Based on our findings, we conclude that the mammalian GnRH-RI is an intracellular GPCR that is expressed on the nuclear membrane. This major and novel discovery causes us to reassess the signaling potential of this physiologically and clinically important receptor.

  9. Role of Gonadotropin-releasing Hormone Stimulation Test in Diagnosing Gonadotropin Deficiency in Both Males and Females with Delayed Puberty

    Institute of Scientific and Technical Information of China (English)

    Qi-Hong Sun; Yu Zheng; Xiao-Lin Zhang; Yi-Ming Mu

    2015-01-01

    Background:Delayed puberty can result either from constitutional delay of growth and puberty (CDP) or idiopathic hypogonadotropic hypogonadism (IHH).Gonadotropin-releasing hormone (GnRH) stimulation test has been generally accepted as a current method for diagnosing delayed puberty.The objective of this research was to assess the cut-off values and the efficacy of GnRH stimulation test in the diagnosis of delayed puberty in both males and females.Methods:A study of 91 IHH,27 CDP patients,6 prepubertal children,and 20 pubertal adults was undertaken.Blood samples were obtained at 0,30,60,and 120 min after GnRH administration and the levels of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) were measured.For each parameter,the sensitivities and specificities were estimated,and the receiver operating characteristic (ROC) curves were constructed.Results:The ROC curves indicated that a serum basal LH <0.6 IU/L or peak LH <9.74 IU/L resulted in moderate sensitivity (73.8% or 80.0%) and specificity (90.9% or 86.4%) in the diagnosis of HH in males.Serum basal LH <0.85 IU/L or basal FSH <2.43 IU/L resulted in moderate sensitivity (80.0% or 100.0%) and specificity (75.0% or 50.0%) in the diagnosis of HH in females.Conclusions:Our data suggest that isolated use of the gonadorelin stimulation test is almost sufficient to discriminate between HH and CDP in males,but unnecessary in females.The most useful predictor is serum basal or peak LH to differentiate these two disorders in males,but serum basal LH or FSH in females.

  10. Effects of administration of gonadotropin-releasing hormone at artificial insemination on conception rates in dairy cows.

    Science.gov (United States)

    Shephard, R W; Morton, J M; Norman, S T

    2014-01-10

    A controlled trial investigating the effect on conception of administration of 250 μg of gonadotropin-releasing hormone (GnRH) at artificial insemination (AI) in dairy cows in seasonal or split calving herds was conducted. Time of detection of estrus, body condition, extent of estrous expression, treatment, breed, age and milk production from the most recent herd test of the current lactation was recorded. Cows were tested for pregnancy with fetal aging between 35 and 135 days after AI. Sixteen herds provided 2344 spring-calved cows and 3007 inseminations. Logistic regression adjusting for clustering at herd level was used to examine the effect of treatment for first (2344) and second (579) inseminations separately. For first AI, treatment significantly improved conception rate in cows with milk protein concentrations of 3.75% or greater and for cows with milk protein concentrations between 3.00% and 3.50% and less than 40 days calved; increased conception rate from 41.2% to 53.4%. Treatment reduced conception rates in cows with milk protein concentrations of 2.75% or less. Treating only cows identified as responding positively to treatment (11% of all study cows) was estimated to increase first service conception rate in herds from 48.1% to 49.4%. There was no significant effect of treatment on conception to second AI, nor any significant interactions. These findings indicate that GnRH at AI should be limited to the sub-group cows most likely to respond. The positive effect of GnRH at AI may be mediated through improved oocyte maturation and/or improved luteal function, rather than by reducing AI-to-ovulation intervals.

  11. An integrated life cycle inventory for demolition processes in the context of life cycle sustainability assessment

    DEFF Research Database (Denmark)

    Bozhilova-Kisheva, Kossara Petrova; Hu, Mingming; van Roekel, Eric

    2012-01-01

    According to the Life Cycle Assessment in Building and Construction: State-of-the-Art Report (2003), the dismantling and demolition stage of the building life cycle is only sometimes included in the Life Cycle Inventory (LCI) when doing Life Cycle Assessments (LCA). The reason that it is less...... inventoried in a traditional LCA maybe because this stage is expected to have a negligible environmental impact comparing to other stages in the life cycle of the buildings. When doing a life cycle sustainability assessment considering not only environmental but also economic and social impacts, the impacts...... of the labor-intensive dismantling and demolition stage may not be possible to disregard anymore, due to the related process costs, health and safety of workers and the influence on the quality of the demolition materials, determining their suitability for high grade recycling. Currently, LCIs of dismantling...

  12. Life Cycle Assessment and Risk Assessment

    DEFF Research Database (Denmark)

    Olsen, Stig Irving

    Life Cycle Assessment (LCA) is a tool for environmental assessment of product and systems – over the whole life cycle from acquisition of raw materials to the end-of-life of the product – and encompassing all environmental impacts of emissions and resource usage, e.g. global warming, acidification...... and toxicity. Whereas Risk Assessment (RA) aims to identify absolute risks, LCA assess potential or relative impacts. LCA is readily applicable to nanotechnologies and several studies have been carried out, but LCA faces large problems when addressing toxic impacts of nanomaterials emitted during the life...... cycle. The models for assessing toxic impacts in LCA are to a large extent based on those developed for RA, e.g. EUSES, and require basic information about the inherent properties of the emissions like solubility, LogKow,ED50 etc. Additionally, it is a prerequisite to know how to characterize...

  13. The Life Cycle of Engineered Nanoparticles.

    Science.gov (United States)

    González-Gálvez, David; Janer, Gemma; Vilar, Gemma; Vílchez, Alejandro; Vázquez-Campos, Socorro

    2017-01-01

    The first years in the twenty-first century have meant the inclusion of nanotechnology in most industrial sectors, from very specific sensors to construction materials. The increasing use of nanomaterials in consumer products has raised concerns about their potential risks for workers, consumers and the environment. In a comprehensive risk assessment or life cycle assessment, a life cycle schema is the starting point necessary to build up the exposure scenarios and study the processes and mechanisms driving to safety concerns. This book chapter describes the processes that usually occur at all the stages of the life cycle of the nano-enabled product, from the nanomaterial synthesis to the end-of-life of the products. Furthermore, release studies reported in literature related to these processes are briefly discussed.

  14. Optimal Life Cycle Portfolio Choice with Housing Market Cycles

    DEFF Research Database (Denmark)

    Fischer, Marcel; Stamos, Michael Z.

    2013-01-01

    In recent decades U.S. households have experienced residential house prices moving persistently, that is, returns being positively serially correlated. We set up a realistically calibrated life cycle model with slow-moving time variation in expected housing returns, showing that not only age, lab...

  15. When Product Life Cycle Meets Customer Activity Cycle

    DEFF Research Database (Denmark)

    Tan, Adrian Ronald

    2007-01-01

    Manufacturing companies have traditionally focused their efforts on designing, developing and producing products to offer on the market. Today global competition and demands for greater company responsibility of products throughout their entire life cycle are driving manufacturing companies...... of products throughout their life cycle by designing integrated solutions of products and services. This approach has been dubbed ‘product/service-systems (PSS)’ (Mont, 2004). Although relationship marketing and product/service-system design have their roots in each their own research fields - marketing...... approaches can be a step on the path to sustainable development as this will enable and motivate companies to reuse, rationalise and enhance their products and services more efficiently throughout their life phases (Manzini & Vezzoli, 2002). Based on a year’s participation and observation in a development...

  16. Implementing Life Cycle Assessment in Product development

    DEFF Research Database (Denmark)

    Bhander, Gurbakhash Singh

    2003-01-01

    The overall aim of the paper is to provide an understanding of the environmental issues involved in the early stages of product development and the capacity of life cycle assessment techniques to address these issues. The paper aims to outline the problems for the designer in evaluating......, and of the opportunities for introducing environmental criteria in the design process through meeting the information requirements of the designer on the different life cycle stages, producing an in-depth understanding of the attitudes of practitioners among product developers to the subject area, and an understanding...... of possible future directions for product development. An Environmentally Conscious Design method is introduced and trade-offs are presented between design degrees of freedom and environmental solutions. Life cycle design frameworks and strategies are addressed. The paper collects experiences and ideas around...

  17. Evolution in the Cycles of Life.

    Science.gov (United States)

    Bowman, John L; Sakakibara, Keiko; Furumizu, Chihiro; Dierschke, Tom

    2016-11-23

    The life cycles of eukaryotes alternate between haploid and diploid phases, which are initiated by meiosis and gamete fusion, respectively. In both ascomycete and basidiomycete fungi and chlorophyte algae, the haploid-to-diploid transition is regulated by a pair of paralogous homeodomain protein encoding genes. That a common genetic program controls the haploid-to-diploid transition in phylogenetically disparate eukaryotic lineages suggests this may be the ancestral function for homeodomain proteins. Multicellularity has evolved independently in many eukaryotic lineages in either one or both phases of the life cycle. Organisms, such as land plants, exhibiting a life cycle whereby multicellular bodies develop in both the haploid and diploid phases are often referred to as possessing an alternation of generations. We review recent progress on understanding the genetic basis for the land plant alternation of generations and highlight the roles that homeodomain-encoding genes may have played in the evolution of complex multicellularity in this lineage.

  18. Recent developments in Life Cycle Assessment

    DEFF Research Database (Denmark)

    Finnveden, Göran; Hauschild, Michael Zwicky; Ekvall, Tomas

    2009-01-01

    Life Cycle Assessment is a tool to assess the environmental impacts and resources used throughout a product’s life cycle, i.e., from raw material acquisition, via production and use phases, to waste management. The methodological development in LCA has been strong, and LCA is broadly applied...... on Life Cycle Impact Assessment we discuss the characteristics of the modelling as well as some recent developments for specific impact categories and weighting. In relation to the Interpretation the focus is on uncertainty analysis. Finally, we discuss recent developments in relation to some...... especially discuss the distinction between attributional and consequential LCA. For the Inventory Analysis, this distinction is relevant when discussing system boundaries, data collection, and allocation. Also highlighted are developments concerning databases and Input–Output and hybrid LCA. In the sections...

  19. Life Cycle assessment of basic chemicals

    DEFF Research Database (Denmark)

    Olsen, Stig Irving

    The present report results as part of a ph.d. project aiming at developing general rules for LCA of basic chemicals. Part 1 reviews the state of the art framework for life-cycle assessment and part 2 relates that framework to the chemical industry and gives some proposals for LCAs of basic...... chemicals. A survey of the use of LCA in the European chemical industry has been conducted and is reported in appendix 1. Life cycle assessment (LCA) is a tool/process to evaluate the potential environmental impacts of a system (most often a product) through its whole life cycle by collecting input...... and output data (together interventions) from all unit processes in the system and assessing the potential environmental impact of these interventions. The LCA framework comprise four phases which are iteratively interlinked: · Goal and scope definition · Inventory · Impact assessment · Interpretation...

  20. Implementing Life Cycle Assessment in Product development

    DEFF Research Database (Denmark)

    Bhander, Gurbakhash Singh

    2003-01-01

    The overall aim of the paper is to provide an understanding of the environmental issues involved in the early stages of product development and the capacity of life cycle assessment techniques to address these issues. The paper aims to outline the problems for the designer in evaluating......, and of the opportunities for introducing environmental criteria in the design process through meeting the information requirements of the designer on the different life cycle stages, producing an in-depth understanding of the attitudes of practitioners among product developers to the subject area, and an understanding...... of possible future directions for product development. An Environmentally Conscious Design method is introduced and trade-offs are presented between design degrees of freedom and environmental solutions. Life cycle design frameworks and strategies are addressed. The paper collects experiences and ideas around...

  1. Weapons barrel life cycle determination

    Directory of Open Access Journals (Sweden)

    Nebojša Pene Hristov

    2013-10-01

    Full Text Available This article describes the dynamic processes within the gun barrel during the firing process in exploitation. It generally defines the basic principles of constructing tube elements, and shows the distortion of the basic geometry of the tube interior due to wear as well as the impact it causes during exploitation. The article also defines basic empirical models as well as a model based on fracture mechanics for the calculation of a use-life of the barrel, and other elements essential for the safe use of the barrel as the basic weapon element. Erosion causes are analysed in order to control and reduce wear and prolong the lifetime of the gun barrel. It gives directions for the reparation of barrels with wasted resources. In conclusion, the most influential elements of tube wear are given as well as possible modifications of existing systems, primarily propellant charges, with a purpose of prolonging lifetime of gun barrels. The guidelines for a proper determination of the lifetime based on the barrel condition assessment are given as well. INTRODUCTION The barrel as the basic element of each weapon is described as well as the processes occurring during the firing that have impulsive character and are accompanied by large amounts of energy. The basic elements of barrel and itheir constructive characteristics are descibed. The relation between Internal ballistics, ie calculation of the propellant gas pressure in the firing process, and structural elements defined by the barrel material resistance is shown. In general, this part of the study explains the methodology of the gun barrel structural elements calculation, ie. barrel geometry, taking into account the degrees of safety in accordance with Military Standards.   TUBE WEAR AND DEFORMATIONS The weapon barrel gradually wears out during exploitation due to which it no longer satisfies the set requirements. It is considered that the barrel has experienced a lifetime when it fails to fulfill the

  2. Pregnancy rates to timed artificial insemination in dairy cows treated with gonadotropin-releasing hormone or porcine luteinizing hormone.

    Science.gov (United States)

    Colazo, M G; Gordon, M B; Rajamahendran, R; Mapletoft, R J; Ambrose, D J

    2009-07-15

    We compared the effects of porcine luteinizing hormone (pLH) versus gonadotropin-releasing hormone (GnRH) on ovulatory response and pregnancy rate after timed artificial insemination (TAI) in 605 lactating dairy cows. Cows (mean+/-SEM: 2.4+/-0.08 lactations, 109.0+/-2.5 d in milk, and 2.8+/-0.02 body condition score) at three locations were assigned to receive, in a 2x2 factorial design, either 100 microg GnRH or 25mg pLH im on Day 0, 500 microg cloprostenol (PGF) on Day 7, and GnRH or pLH on Day 9, with TAI 14 to 18h later. Ultrasonographic examinations were performed in a subset of cows on Days 0, 7, 10, and 11 to determine ovulations, presence of corpus luteum, and follicle diameter and in all cows 32 d after TAI for pregnancy determination. In 35 cows, plasma progesterone concentrations were determined 0, 3, 4, 5, 6, 7, and 12 d after ovulation. The proportion of noncyclic cows and cows with ovarian cysts on Day 0 were 12% and 6%, respectively. Ovulatory response to first treatment was 62% versus 44% for pLH and GnRH and 78% versus 50% for noncyclic and cyclic cows (PpLH or GnRH, cyclic status, presence of an ovarian cyst, and preovulatory follicle size did not affect pregnancy rate. Plasma progesterone concentrations after TAI did not differ among treatments. Pregnancy rate to TAI was greater (PpLH group (42%) than in the other three groups (28%, 30%, and 26% for GnRH/PGF/GnRH, pLH/PGF/GnRH, and pLH/PGF/pLH, respectively). Although only 3% of cows given pLH in lieu of GnRH on Day 9 lost their embryo versus 7% in those subjected to a conventional TAI using two GnRH treatments, the difference was not statistically significant. In summary, pLH treatment on Day 0 increased ovulatory response but not pregnancy rate. Cows treated with GnRH/PGF/pLH had the highest pregnancy rate to TAI, but progesterone concentrations after TAI were not increased. In addition, preovulatory follicle diameter did not affect pregnancy rate.

  3. Comparing the Life Cycle Energy Consumption, Global ...

    Science.gov (United States)

    Managing the water-energy-nutrient nexus for the built environment requires, in part, a full system analysis of energy consumption, global warming and eutrophication potentials of municipal water services. As an example, we evaluated the life cycle energy use, greenhouse gas (GHG) emissions and aqueous nutrient releases of the whole anthropogenic municipal water cycle starting from raw water extraction to wastewater treatment and reuse/discharge for five municipal water and wastewater systems. The assessed options included conventional centralized services and four alternative options following the principles of source-separation and water fit-for-purpose. The comparative life cycle assessment identified that centralized drinking water supply coupled with blackwater energy recovery and on-site greywater treatment and reuse was the most energyand carbon-efficient water service system evaluated, while the conventional (drinking water and sewerage) centralized system ranked as the most energy- and carbon-intensive system. The electricity generated from blackwater and food residuals co-digestion was estimated to offset at least 40% of life cycle energy consumption for water/waste services. The dry composting toilet option demonstrated the lowest life cycle eutrophication potential. The nutrients in wastewater effluent are the dominating contributors for the eutrophication potential for the assessed system configurations. Among the parameters for which variability

  4. Asset Allocation Over the Life Cycle

    DEFF Research Database (Denmark)

    Fischer, Marcel; Kraft, Holger; Munk, Claus

    2013-01-01

    We study the welfare effect of tax-optimizing portfolio decisions in a life cycle model with unspanned labor income and realization-based capital gain taxation. For realistic parameterizations of our model, certainty equivalent welfare gains from fully tax-optimized portfolio decisions are less...... with strong bequest motives face substantial welfare costs when not tax-optimizing their portfolio decisions towards the end of the life cycle....... than 2% of present financial wealth and lifetime income compared to a heuristic portfolio policy ignoring the taxation of profits (capital gains, interest and dividend payments). Compared to a heuristic portfolio policy that only ignores the realization-based feature of capital gain taxation...

  5. An Integrated Framework for Life Cycle Engineering

    DEFF Research Database (Denmark)

    Hauschild, Michael Zwicky; Herrmann, Christoph; Kara, Sami

    2017-01-01

    has broadened, and as a result, LCE has evolved in parallel with other disciplines with similar aims. Currently, in addition to LCE, there exist a number of concepts such as Industrial Ecology, Cleaner Production, Life Cycle Management (LCM), Industrial Symbiosis, and Circular Economy. As a result......Life Cycle Engineering (LCE) was introduced as a concept more than 24 years ago in order to address emerging concerns about environmental sustainability in engineering. A number of methods and tools have been introduced to operationalise the LCE concept, but since then, the scope of sustainability...

  6. Life cycle assessment of renewable energy sources

    CERN Document Server

    Singh, Anoop; Olsen, Stig Irving

    2013-01-01

    Governments are setting challenging targets to increase the production of energy and transport fuel from sustainable sources. The emphasis is increasingly on renewable sources including wind, solar, geothermal, biomass based biofuel, photovoltaics or energy recovery from waste. What are the environmental consequences of adopting these other sources? How do these various sources compare to each other? Life Cycle Assessment of Renewable Energy Sources tries to answer these questions based on the universally adopted method of Life Cycle Assessment (LCA). This book introduces the concept and impor

  7. Cycle life sensor for rechargeable lithium batteries

    Science.gov (United States)

    Nanjundiah, C.; Koch, V. R.

    The problem of characterizing the state of a rechargeable Li battery as a function of cycle life history was addressed. A 50-micron dia Pt microelectrode embedded in the cell package was used as a sensing electrode. Good correlations between Li stripping currents and cycle life were achieved in Li/Li half cells. However, no systematic trends were observed in Li/TiS2 ful cells. Additionally, Li-electrolyte degradation products were found to be either insoluble or electroinactive over the available electrochemical window.

  8. Life-Cycle Cost-Benefit Analysis

    DEFF Research Database (Denmark)

    Thoft-Christensen, Palle

    2010-01-01

    The future use of Life-Cycle Cost-Benefit (LCCB) analysis is discussed in this paper. A more complete analysis including not only the traditional factors and user costs, but also factors which are difficult to include in the analysis is needed in the future.......The future use of Life-Cycle Cost-Benefit (LCCB) analysis is discussed in this paper. A more complete analysis including not only the traditional factors and user costs, but also factors which are difficult to include in the analysis is needed in the future....

  9. Two gonadotropin-releasing hormone receptor subtypes with distinct ligand selectivity and differential distribution in brain and pituitary in the goldfish (Carassius auratus)

    OpenAIRE

    Illing, Nicola; Troskie, Brigitte E.; Nahorniak, Carol S.; Janet P Hapgood; Peter, Richard E.; Millar, Robert P.

    1999-01-01

    In the goldfish (Carassius auratus) the two endogenous forms of gonadotropin-releasing hormone (GnRH), namely chicken GnRH II ([His5,Trp7,Tyr8]GnRH) and salmon GnRH ([Trp7,Leu8]GnRH), stimulate the release of both gonadotropins and growth hormone from the pituitary. This control is thought to occur by means of the stimulation of distinct GnRH receptors. These receptors can be distinguished on the basis of differential gonadotropin and growth hormone releasing activities of naturally occurring...

  10. Gonadotropin-releasing hormone receptor (Gnrhr) gene knock out: Normal growth and development of sensory, motor and spatial orientation behavior but altered metabolism in neonatal and prepubertal mice

    OpenAIRE

    Busby, Ellen R.; Sherwood, Nancy M.

    2017-01-01

    Gonadotropin-releasing hormone (GnRH) is important in the control of reproduction, but its actions in non-reproductive processes are less well known. In this study we examined the effect of disrupting the GnRH receptor in mice to determine if growth, metabolism or behaviors that are not associated with reproduction were affected. To minimize the effects of other hormones such as FSH, LH and sex steroids, the neonatal-prepubertal period of 2 to 28 days of age was selected. The study shows that...

  11. Expression of Two Gonadotropin-Releasing Hormone (GnRH) Precursor Genes in Various Tissues of the Japanese Eel and Evolution of GnRH(Endocrinology)

    OpenAIRE

    Kataaki, Okubo; Hiroaki, Suetake; KATSUMI, AIDA; Department of Aquatic Bioscience, Graduate School of Agricultural and Life Sciences, The University of Tokyo

    1999-01-01

    We isolated and characterized two distinct cDNAs for mammalian gonadotropin-releasing hormone (mGnRH) and chicken GnRH-ll (cGnRH-ll) precursors from the Japanese eel by rapid amplification of cDNA ends. Each GnRH precursors were composed of a signal peptide, a GnRH decapeptide, a processing site and a GnRH-associated peptide. Northern blot and reverse transcription-polymerase chain reaction analysis revealed that the mGnRH precursor gene is expressed in all tissues tested including the brain,...

  12. Life-cycle cost analysis of adsorption cycles for desalination

    KAUST Repository

    Thu, Kyaw

    2010-08-01

    This paper presents the thermo-economic analysis of the adsorption desalination (AD) cycle that is driven by low-temperature waste heat from exhaust of industrial processes or renewable sources. The AD cycle uses an adsorbent such as the silica gel to desalt the sea or brackish water. Based on an experimental prototype AD plant, the life-cycle cost analysis of AD plants of assorted water production capacities has been simulated and these predictions are translated into unit cost of water production. Our results show that the specific energy consumption of the AD cycle is 1.38 kWh/m3 which is the lowest ever reported. For a plant capacity of 1000 m3/d, the AD cycle offers a unit cost of $0.457/m3 as compared to more than $0.9 for the average RO plants. Besides being cost-effective, the AD cycle is also environment-friendly as it emits less CO2 emission per m3 generated, typically 85% less, by comparison to an RO process. © 2010 Desalination Publications.

  13. 10 CFR 436.12 - Life cycle cost methodology.

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 3 2010-01-01 2010-01-01 false Life cycle cost methodology. 436.12 Section 436.12 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION FEDERAL ENERGY MANAGEMENT AND PLANNING PROGRAMS Methodology and Procedures for Life Cycle Cost Analyses § 436.12 Life cycle cost methodology. The life cycle cost methodology...

  14. Managing the Life Cycle Risks of Nanomaterials

    Science.gov (United States)

    2009-07-01

    International Center for Scholars Project on Emerging Nanotechnologies (PEN) consumer products inventory, 16 is found in wound dressings, socks, and soap...acceptance authority. 8. Track hazards, their closures , and residual mishap risk throughout the system life cycle. When properly applied, the...Risks of Nanomaterials Report consumption, land use, ozone depletion, global warming, acidification, eutrophication, tropospheric ozone formation

  15. Estimating the Value Added Product Life Cycle

    OpenAIRE

    Gedikoglu, Haluk; Parcell, Joseph L.; Patterson, David J.; Randle, Richard

    2006-01-01

    This research analyzes factors affecting product and profit life-cycles for new value added products. The methodology used shows how sales and profits evolve and how exogenous factors affecting sales and profits. Results indicate that producers can increase the level of sales and profits over time through initial marketing efforts.

  16. Life Cycle Assessment in Spatial Planning

    DEFF Research Database (Denmark)

    Bidstrup, Morten; Pizzol, Massimo; Schmidt, Jannick Højrup

    2015-01-01

    the spatial boundaries of a plan to further focus on global, indirect and cumulative impacts. These impacts are referred to as “systemic impacts”. This study proposes a Life Cycle Assessment (LCA) procedure which can be adopted in SEAs of various types of planning. The procedure represents a first step...

  17. Life Cycle Assessment of Sugar Production (VB)

    DEFF Research Database (Denmark)

    Teljigovic, Mehmed; Mengiardi, Jon; Factor, Gabriela

    1999-01-01

    will be made between sugar from sugar beet produced in Denmark versus sugar produces from sugar cane in a tropical country, Brazil, and transported afterwards to Denmark. To evaluate the environmental aspects of these two product systems a Life Cycle Assessement (LCA) will be carried out.From the results...

  18. Planning Evaluation through the Program Life Cycle

    Science.gov (United States)

    Scheirer, Mary Ann; Mark, Melvin M.; Brooks, Ariana; Grob, George F.; Chapel, Thomas J.; Geisz, Mary; McKaughan, Molly; Leviton, Laura

    2012-01-01

    Linking evaluation methods to the several phases of a program's life cycle can provide evaluation planners and funders with guidance about what types of evaluation are most appropriate over the trajectory of social and educational programs and other interventions. If methods are matched to the needs of program phases, evaluation can and should…

  19. Women's Place in Man's Life Cycle.

    Science.gov (United States)

    Gilligan, Carol

    1979-01-01

    Drawing on literary and psychological sources, the author documents how theories of the life cycle, by taking men as models, have failed to account for the experience of women. She argues that this bias has promoted a concern with autonomy and achievement at the expense of attachment and intimacy. (CT)

  20. The life cycle of social media

    NARCIS (Netherlands)

    Ph.H.B.F. Franses (Philip Hans)

    2014-01-01

    markdownabstract__Abstract__ Using weekly data on the interest for 17 social media via Google trends and using quarterly data on actual users for 3 social media, it is reported in this letter that the life cycles of social media mimic those of durable consumer goods. On average, the popularity of

  1. Product Life Cycle - Quality Management Issues

    DEFF Research Database (Denmark)

    Alting, Leo; Majstorovic, Vidosav D.

    2004-01-01

    The strategic goal of our country is European and world integration. Within this context the management of sustainable development considered from the aspect of product’s life cycle and its quality management represents a real challenge for researchers, economy and educational system. The aim...

  2. Farinon microwave end of life cycle

    Energy Technology Data Exchange (ETDEWEB)

    Poe, R.C.

    1996-06-24

    This engineering report evaluates alternatives for the replacement of the Farinon microwave radio system. The system is beyond its expected life cycle and has decreasing maintainability. Principal applications supported by the Farinon system are two electrical utility monitor and control systems, the Integrated Transfer Trip System (ITTS), and the Supervisory Control and Data Acquisition (SCADA) system.

  3. Life cycle characteristics of SME’s

    NARCIS (Netherlands)

    Masurel, E.; Montfort, van K.

    2006-01-01

    Our study of professional services firms clearly revealed that firms change over the course of their life cycles. During the first three stages, diversification in sales, the differentiation in labor force, and the level of labor productivity increase. In the last stage, diversification in sales, th

  4. Semantic catalogs for life cycle assessment data

    NARCIS (Netherlands)

    Kuczenski, Brandon; Davis, Christopher B.; Rivela, Beatriz; Janowicz, Krzysztof

    2016-01-01

    Life cycle assessment (LCA) is a highly interdisciplinary field that requires knowledge from different domains to be gathered and interpreted together. Although there are relatively few major data sources for LCA, the data themselves are presented with highly heterogeneous formats, interfaces, and

  5. Semantic catalogs for life cycle assessment data

    NARCIS (Netherlands)

    Kuczenski, Brandon; Davis, Christopher B.; Rivela, Beatriz; Janowicz, Krzysztof

    2016-01-01

    Life cycle assessment (LCA) is a highly interdisciplinary field that requires knowledge from different domains to be gathered and interpreted together. Although there are relatively few major data sources for LCA, the data themselves are presented with highly heterogeneous formats, interfaces, and d

  6. Product Life Cycle - Quality Management Issues

    DEFF Research Database (Denmark)

    Alting, Leo; Majstorovic, Vidosav D.

    2004-01-01

    The strategic goal of our country is European and world integration. Within this context the management of sustainable development considered from the aspect of product’s life cycle and its quality management represents a real challenge for researchers, economy and educational system. The aim...

  7. Implementing Life Cycle Assessment in systems development

    DEFF Research Database (Denmark)

    Bhander, Gurbakhash Singh; Hauschild, Michael Zwicky; McAloone, Timothy Charles

    2003-01-01

    derived from products and system, and calculate resource consumptions. However, the complexity of LCA poses restrictions to its use in current product and system development given the need for a reduction in product development cycle time which is needed to meet the increasing competitive pressures....... The paper reviews the current environmental evaluation practices with respect to product life cycles. As a number of deficiencies in LCA are identified, strategies are presented to provide a solution to many of the deficiencies. The result of the paper is a definition of the requirements for performance...... measurement techniques and a performance measurement environment necessary to support life cycle evaluation throughout the evaluation of early stages of a product system....

  8. Implementing Life Cycle Assessment in systems development

    DEFF Research Database (Denmark)

    Bhander, Gurbakhash Singh; Hauschild, Michael Zwicky; McAloone, Timothy Charles

    2003-01-01

    derived from products and system, and calculate resource consumptions. However, the complexity of LCA poses restrictions to its use in current product and system development given the need for a reduction in product development cycle time which is needed to meet the increasing competitive pressures...... and the rapid changes in markets for many products. The overall aim of the paper is to provide an understanding of the environmental issues involved in the early stages of product development and the capacity of life cycle assessment techniques to address these issues. The paper aims to outline the problems...... of the barriers to implementation of LCA by developers of products, and of the opportunities for introducing environmental criteria in the design process through meeting the information requirements of the designer on the different life cycle stages, producing an in-depth understanding of the attitudes...

  9. Life Cycle Assessment and Risk Assessment

    DEFF Research Database (Denmark)

    Olsen, Stig Irving

    Life Cycle Assessment (LCA) is a tool for environmental assessment of product and systems – over the whole life cycle from acquisition of raw materials to the end-of-life of the product – and encompassing all environmental impacts of emissions and resource usage, e.g. global warming, acidification...... the emissions, how should they be defined and classified and what should be measured? LCA have many of these issues in common with RA. There is a need to understand which properties of nanomaterials are crucial for the assessment of their potential transformation and fate as well as their ability to cause...... adverse effects on target organisms or systems. If we want to be able to assess toxic impacts both in LCA and in RA these issues need to be addressed by the RA community and the LCA community must follow closely the progress made....

  10. Optimization of life cycle management costs

    Energy Technology Data Exchange (ETDEWEB)

    Banerjee, A.K. [Stone & Webster Engineering Corp., Boston, MA (United States)

    1994-12-31

    As can be seen from the case studies, a LCM program needs to address and integrate, in the decision process, technical, political, licensing, remaining plant life, component replacement cycles, and financial issues. As part of the LCM evaluations, existing plant programs, ongoing replacement projects, short and long-term operation and maintenance issues, and life extension strategies must be considered. The development of the LCM evaluations and the cost benefit analysis identifies critical technical and life cycle cost parameters. These {open_quotes}discoveries{close_quotes} result from the detailed and effective use of a consistent, quantifiable, and well documented methodology. The systematic development and implementation of a plant-wide LCM program provides for an integrated and structured process that leads to the most practical and effective recommendations. Through the implementation of these recommendations and cost effective decisions, the overall power production costs can be controlled and ultimately lowered.

  11. A Community Membership Life Cycle Model

    CERN Document Server

    Sonnenbichler, Andreas C

    2010-01-01

    Web 2.0 is transforming the internet: Information consumers become information producers and consumers at the same time. In virtual places like Facebook, Youtube, discussion boards and weblogs diversificated topics, groups and issues are propagated and discussed. Today an internet user is a member of lots of communities at different virtual places. "Real life" group membership and group behavior has been analyzed in science intensively in the last decades. Most interestingly, to our knowledge, user roles and behavior have not been adapted to the modern internet. In this work, we give a short overview of traditional community roles. We adapt those models and apply them to virtual online communities. We suggest a community membership life cycle model describing roles a user can take during his membership in a community. Our model is systematic and generic; it can be adapted to concrete communities in the web. The knowledge of a community's life cycle allows influencing the group structure: Stage transitions can...

  12. Chromosomal localization of the gonadotropin-releasing hormone receptor gene to human chromosome 4q13. 1-q21. 1 and mouse chromosome 5

    Energy Technology Data Exchange (ETDEWEB)

    Kaiser, U.B.; Dushkin, H.; Beier, D.R.; Chin, W.W. (Harvard Medical School, Boston, MA (United States)); Altherr, M.R. (Los Alamos National Lab., NM (United States))

    1994-04-01

    The gonadotropin-releasing hormone receptor (GRHR) is a G-protein-coupled receptor on the cell surface of pituitary gonadotropes, where it serves to transduce signals from the extracellular ligand, the hypothalamic factor gonadotropin-releasing hormone, and to modulate the synthesis and secretion of luteinizing hormone and follicle-stimulating hormone. The authors have localized the GRHR gene to the q13.1-q21.1 region of the human chromosome 4 using mapping panels of human/rodent somatic cell hybrids containing different human chromosomes or different regions of human chromosome 4. Furthermore, using linkage analysis of single-strand conformational polymorphisms, the murine GRHR gene was localized to mouse chromosome 5, linked to the endogenous retroviral marker Pmv-11. This is consistent with the evolutionary conservation of homology between these two regions, as has been previously suggested from comparative mapping of several other loci. The localization of the GRHR gene may be useful in the study of disorders of reproduction. 22 refs., 2 figs.

  13. Generalizing Agile Software Development Life Cycle

    Directory of Open Access Journals (Sweden)

    S. Bhalerao

    2009-11-01

    Full Text Available In last decade, various agile methods have been introduced and used by software industry. It has been observed that many practitioners are using hybrid of agile methods and traditional methods. The knowledge of agile software development process about the theoretical grounds, applicability in large development settings and connections to establish software engineering disciplines remain mostly in dark. It has been reported that it is difficult for average manager to implement agile method in the organization. Further, every agile method has its own development cycle that brings technological, managerial and environmental changes in organization. A proper roadmap of agile software development in the form of agile software development life cycle can be developed to address the aforesaid issues of agile software development process. Thus, there is strong need of agile software development life cycle that clearly defines the phases included in any agile method and also describes the artifacts of each phase. This generalization of agile software development life cycle provides the guideline for average developers about usability, suitability, applicability of agile methods.

  14. Uncertainty in Life Cycle Assessment of Nanomaterials

    Science.gov (United States)

    Seager, T. P.; Linkov, I.

    Despite concerns regarding environmental fate and toxicology, engineered nanostructured material manufacturing is expanding at an increasingly rapid pace. In particular, the unique properties of single walled carbon nanotubes (SWCNT) have made them attractive in many areas, including high-tech power applications such as experimental batteries, fuel cells or electrical wiring. The intensity of research interest in SWCNT has raised questions regarding the life cycle environmental impact of nanotechnologies, including assessment of: worker and consumer safety, greenhouse gas emissions, toxicological risks associated with production or product emissions and the disposition of nanoproducts at end of life. However, development of appropriate nanotechnology assessment tools has lagged progress in the nanotechnologies themselves. In particular, current approaches to life cycle assessment (LCA) — originally developed for application in mature manufacturing industries such as automobiles and chemicals — suffer from several shortcomings that make applicability to nanotechnologies problematic. Among these are uncertainties related to the variability of material properties, toxicity and risk, technology performance in the use phase, nanomaterial degradation and change during the product life cycle and the impact assessment stage of LCA. This chapter expounds upon the unique challenges presented by nanomaterials in general, specifies sources of uncertainty and variability in LCA of SWCNT for use in electric and hybrid vehicle batteries and makes recommendations for modeling and decision-making using LCA in a multi-criteria decision analysis framework under conditions of high uncertainty.1

  15. Comparative life cycle assessment and life cycle costing of lodging in the Himalaya

    DEFF Research Database (Denmark)

    Bhochhibhoya, Silu; Pizzol, Massimo; Achten, Wouter M J

    2016-01-01

    and economic burden in future construction projects. Methods The study consists of the life cycle assessment and life cycle costing of lodging in three building types: traditional, semi-modern and modern. The life cycle stages under analysis include raw material acquisition, manufacturing, construction, use......, a breakdown of the building components shows that the roof and wall of the building are the largest contributors to the production-related environmental impact. Conclusions The findings suggest that the main improvement opportunities in the lodging sector lie in the reduction of impacts on the use stage......Purpose The main aim of the study is to assess the environmental and economic impacts of the lodging sector located in the Himalayan region of Nepal, from a life cycle perspective. The assessment should support decision making in technology and material selection for minimal environmental...

  16. Confronting product life thinking with product life cycle analysis

    DEFF Research Database (Denmark)

    McAloone, Tim C.

    2001-01-01

    Industry is increasingly being confronted with the need to consider the whole life cycle effects of its products, in order to make environmental improvements of any significance. There is a danger that naive environmental decisions are made, due to apparent lack of data or actual lack of insight....... This paper describes a case study, where a class of students was presented with a product from the Danish company, Danfoss A/S, and given the task of carrying out an initial environmental evaluation of the product. This evaluation consisted of both a "life cycle check" and an exercise where the students were...... to "read" the environment out of the product, in order to systematically, quickly and efficiently come to some design recommendations for the company. The phrases "LCA" and "product life thinking" will be described and differentiated and a pattern identified for their cooperative effect in use....

  17. Life cycle assessment of electronic waste treatment

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Jinglan, E-mail: hongjing@sdu.edu.cn [Shandong Provincial Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Jinan 250100 (China); Shandong University Climate Change and Health Center, Public Health School, Shandong University, Jinan 250012 (China); Shi, Wenxiao [Shandong Provincial Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Jinan 250100 (China); Wang, Yutao [School of Life Science, Shandong University, Shanda South Road 27, Jinan 250100 (China); Chen, Wei [Shandong Provincial Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Jinan 250100 (China); Li, Xiangzhi, E-mail: xiangzhi@sdu.edu.cn [School of Medicine, Shandong University, Jinan 250012 (China)

    2015-04-15

    Highlights: • Life cycle assessment of electronic waste recycling is quantified. • Key factors for reducing the overall environmental impact are indentified. • End-life disposal processes provide significant environmental benefits. • Efficiently reduce the improper disposal amount of e-waste is highly needed. • E-waste incineration can generate significant environmental burden. - Abstract: Life cycle assessment was conducted to estimate the environmental impact of electronic waste (e-waste) treatment. E-waste recycling with an end-life disposal scenario is environmentally beneficial because of the low environmental burden generated from human toxicity, terrestrial ecotoxicity, freshwater ecotoxicity, and marine ecotoxicity categories. Landfill and incineration technologies have a lower and higher environmental burden than the e-waste recycling with an end-life disposal scenario, respectively. The key factors in reducing the overall environmental impact of e-waste recycling are optimizing energy consumption efficiency, reducing wastewater and solid waste effluent, increasing proper e-waste treatment amount, avoiding e-waste disposal to landfill and incineration sites, and clearly defining the duties of all stakeholders (e.g., manufacturers, retailers, recycling companies, and consumers)

  18. Life cycle and sustainability of abrasive tools

    CERN Document Server

    Linke, Barbara

    2016-01-01

    This monograph focuses on abrasive tools for grinding, polishing, honing, and lapping operations. The book describes the life cycle of abrasive tools from raw material processing of abrasive grits and bonding, manufacturing of monolithic or multi-layered tools, tool use to tool end-of-life. Moreover, this work highlights sustainability challenges including economic, environmental, social and technological aspects. The target audience primarily comprises research and industry experts in the field of manufacturing, but the book may also be beneficial for graduate students.

  19. Life cycle assessment of mobile phone housing

    Institute of Scientific and Technical Information of China (English)

    YANG Jian-xin; WANG Ru-song; FU Hao; LIU Jing-ru

    2004-01-01

    The life cycle assessment of the mobile phone housing in Motorola(China) Electronics Ltd. was carried out, in which materials flows and environmental emissions based on a basic production scheme were analyzed and assessed. In the manufacturing stage, such primary processes as polycarbonate molding and surface painting are included, whereas different surface finishing technologies like normal painting, electroplate, IMD and VDM etc. were assessed. The results showed that housing decoration plays a significant role within the housing life cycle. The most significant environmental impact from housing production is the photochemical ozone formation potential.Environmental impacts of different decoration techniques varied widely, for example, the electroplating technique is more environmentally friendly than VDM. VDM consumes much more energy and raw material. In addition, the results of two altemative scenarios of dematerialization showed that material flow analysis and assessment is very important and valuable in selecting an environmentally friendly process.

  20. Life cycle management in product development

    DEFF Research Database (Denmark)

    Skelton, Kristen; Pattis, Anna

    2013-01-01

    The integration of Life Cycle Thinking (LCT) and Life Cycle Management (LCM) into business operations poses great challenges, as it requires a wider range of environmental responsibility often extending beyond a company's immediate control. Simultaneously, it offers many opportunities such as the...... in the innovation and design phases. This comparative analysis explores the various approaches and challenges two companies are currently facing in their attempts to integrate LCT into their core product development processes....... such as the reduction of a product's or industry’s environmental impacts, an increase in process efficiency or the interconnectedness within the organization itself or across a supply chain. Product development has been an area where application of LCM has been discussed most, since most product impacts are determined...

  1. LIFE CYCLE COST ANALYSIS OF SOLAR PONDS

    Directory of Open Access Journals (Sweden)

    Murat ÖZTÜRK

    2008-03-01

    Full Text Available Solar ponds are the systems which collect solar energy and store it for long periods of time. For effective and efficient use of these systems in the country, concepts relating economy of solar ponds which generated hot water from the sun must be known besides their physical properties. Life cycle cost analysis is a systematic analytical method that helps identify and evaluate the environmental impacts of a specific process or competing processes. In order to quantify the costs, resource consumption, and energy use, material and energy balances are performed in a cradle-to-grave manner on the operations required to transform raw materials into useful products. In this study; life cycle cost analysis of reflecting covered and non covered solar ponds are calculated for a volume of 3.5x3.5x2 cubic meters and presented. Also the energies extractable for these solar ponds in Goller Region climatic conditions are given.

  2. Life cycle assessment of waste paper management

    DEFF Research Database (Denmark)

    Merrild, Hanna Kristina; Damgaard, Anders; Christensen, Thomas Højlund

    2008-01-01

    The significance of technical data, as well as the significance of system boundary choices, when modelling the environmental impact from recycling and incineration of waste paper has been studied by a life cycle assessment focusing oil global warming potentials. The consequence of choosing a spec...... of scientific discussion on how to best address system analysis of recycling, for paper and other recyclable materials.......The significance of technical data, as well as the significance of system boundary choices, when modelling the environmental impact from recycling and incineration of waste paper has been studied by a life cycle assessment focusing oil global warming potentials. The consequence of choosing...... a specific set of data for the reprocessing technology, the virgin paper manufacturing technology and the incineration technology, as well as the importance of the recycling rate Was Studied. Furthermore, the system was expanded to include forestry and to include fossil fuel energy substitution from saved...

  3. Methodologies for Social Life Cycle Assessment

    DEFF Research Database (Denmark)

    Jørgensen, Andreas; Le Bocq, Agathe; Nazakina, Liudmila

    2008-01-01

    Goal, Scope and Background. In recent years several different approaches towards Social Life Cycle Assessment (SLCA) have been developed. The purpose of this review is to compare these approaches in order to highlight methodological differences and general shortcomings. SLCA has several...... stage in the product life cycle. Another very important difference among the proposals is their position towards the use of generic data. Several of the proposals argue that social impacts are connected to the conduct of the company leading to the conclusion that each individual company in the product...... and formulation of indicators. The indicators address a wide variety of issues; some approaches focus on impacts created in the very close proximity of the processes included in the product system, whereas others focus on the more remote societal consequences. Only very little focus has been given to the use...

  4. Life Cycle Thinking in Impact Assessment

    DEFF Research Database (Denmark)

    Bidstrup, Morten

    2015-01-01

    It has been advocated that life cycle thinking (LCT) should be applied in impact assessment (IA) to a greater extent, since some development proposals pose a risk of significant impacts throughout the interconnected activities of product systems. Multiple authors have proposed the usage of life...... cycle assessment (LCA) for such analytical advancement, but little to no research on this tool application has been founded in IA practice so far. The aim of this article is to elaborate further on the gains assigned to application of LCA. The research builds on a review of 85 Danish IA reports, which...... reveal that LCT is appropriate for most of the IAs, but that LCA is rarely applied to provide such a perspective. Without LCA, the IAs show mixed performance in regard to LCT. Most IAs do consider the product provision of development proposals, but they rarely relate impacts to this function explicitly...

  5. Life-cycle design for sustainable architecture

    Directory of Open Access Journals (Sweden)

    Francesca Thiébat

    2013-05-01

    Full Text Available Sustainability in architecture should involve environmental and social aspects and also economic aspects. However, in a design process budget issues usually outweigh ecological aspects. How can we then drive clients and builders to put more socially responsible buildings on the market that do not exceed the fixed budget but are environmentally friendly? This paper propose an economic and environmental assessment tool to aid private or public building designers and owners to find the global sustainability value of a green building within a life cycle perspective. Sustainable life cycle tools for buildings design and construction help to achieve successfully integrated architecture. The research here presented proposes a new point of view of the “time-cost-quality triangle” of Project Management, by introducing three further aspects: environment, society and aesthetics.

  6. Learning, diffusion and the industry life cycle

    OpenAIRE

    Zhu Wang

    2006-01-01

    An industry typically experiences initial mass entry and later shakeout of producers over its life cycle. It can be explained as a competitive equilibrium outcome driven by the dynamic interaction between technology progress and demand diffusion. When a new product is introduced, high-income consumers tend to adopt it first. Technology then improves with cumulative output and demand growth generates S-shaped diffusion as the product penetrates lower-income groups. Eventually fewer new adopter...

  7. Life Cycles of Ad Hoc Task Groups

    Science.gov (United States)

    1983-10-01

    solving development raises some final questions. If groups are normally preoccupied with different issues at different times, if their capabilities change...context, and group across the group’s life cycle? If such modifications normally occur, there could be substantial implications, both for our theoretical...This, and Diane’s impatient question "What are we accomplishing then?" suggest the Iroup’s need to stop trying to coax the attractive first solucion

  8. 19 CFR 207.27 - Short life cycle products.

    Science.gov (United States)

    2010-04-01

    ... 19 Customs Duties 3 2010-04-01 2010-04-01 false Short life cycle products. 207.27 Section 207.27... SUBSIDIZED EXPORTS TO THE UNITED STATES Final Determinations, Short Life Cycle Products § 207.27 Short life... scope of the product category into which to classify the short life cycle merchandise identified by the...

  9. Conceptual Framework To Extend Life Cycle Assessment ...

    Science.gov (United States)

    Life Cycle Assessment (LCA) is a decision-making tool that accounts for multiple impacts across the life cycle of a product or service. This paper presents a conceptual framework to integrate human health impact assessment with risk screening approaches to extend LCA to include near-field chemical sources (e.g., those originating from consumer products and building materials) that have traditionally been excluded from LCA. A new generation of rapid human exposure modeling and high-throughput toxicity testing is transforming chemical risk prioritization and provides an opportunity for integration of screening-level risk assessment (RA) with LCA. The combined LCA and RA approach considers environmental impacts of products alongside risks to human health, which is consistent with regulatory frameworks addressing RA within a sustainability mindset. A case study is presented to juxtapose LCA and risk screening approaches for a chemical used in a consumer product. The case study demonstrates how these new risk screening tools can be used to inform toxicity impact estimates in LCA and highlights needs for future research. The framework provides a basis for developing tools and methods to support decision making on the use of chemicals in products. This paper presents a conceptual framework for including near-field exposures into Life Cycle Assessment using advanced human exposure modeling and high-throughput tools

  10. An ideal sealed source life-cycle

    Energy Technology Data Exchange (ETDEWEB)

    Tompkins, Joseph Andrew [Los Alamos National Laboratory

    2009-01-01

    we have today. This regulation created a new regulatory framework seen as promising at the time. However, now they recognize that, despite the good intentions, the NIJWP/85 has not solved any source disposition problems. The answer to these sealed source disposition problems is to adopt a philosophy to correct these regulatory issues, determine an interim solution, execute that solution until there is a minimal backlog of sources to deal with, and then let the mechanisms they have created solve this problem into the foreseeable future. The primary philosophical tenet of the ideal sealed source life cycle follows. You do not allow the creation (or importation) of any source whose use cannot be justified, which cannot be affordably shipped, or that does not have a well-delinated and affordable disposition pathway. The path forward dictates that we fix the problem by embracing the Ideal Source Life cycle. In figure 1, we can see some of the elements of the ideal source life cycle. The life cycle is broken down into four portions, manufacture, use, consolidation, and disposition. These four arbitrary elements allow them to focus on the ideal life cycle phases that every source should go through between manufacture and final disposition. As we examine the various phases of the sealed source life cycle, they pick specific examples and explore the adoption of the ideal life cycle model.

  11. Cotton Life Cycle Inventory & Life Cycle Assessment--A Landmark Benchmark for Cotton Sustainability

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Recently, Cotton Incorporated announced the completion of a comprehensive life cycle inventory and life cycJe analysis of cotton products. The endeavor is part of the Cotton Foundation VlSIQN 21 Project and included the participation of the National Cotton Council, Cotton Council International and Cotton Incorporated. The two-year study, managed by PE International,

  12. Life cycle assessment of electronic waste treatment.

    Science.gov (United States)

    Hong, Jinglan; Shi, Wenxiao; Wang, Yutao; Chen, Wei; Li, Xiangzhi

    2015-04-01

    Life cycle assessment was conducted to estimate the environmental impact of electronic waste (e-waste) treatment. E-waste recycling with an end-life disposal scenario is environmentally beneficial because of the low environmental burden generated from human toxicity, terrestrial ecotoxicity, freshwater ecotoxicity, and marine ecotoxicity categories. Landfill and incineration technologies have a lower and higher environmental burden than the e-waste recycling with an end-life disposal scenario, respectively. The key factors in reducing the overall environmental impact of e-waste recycling are optimizing energy consumption efficiency, reducing wastewater and solid waste effluent, increasing proper e-waste treatment amount, avoiding e-waste disposal to landfill and incineration sites, and clearly defining the duties of all stakeholders (e.g., manufacturers, retailers, recycling companies, and consumers).

  13. Life Cycle Assessment of Completely Recyclable Concrete.

    Science.gov (United States)

    De Schepper, Mieke; Van den Heede, Philip; Van Driessche, Isabel; De Belie, Nele

    2014-08-21

    Since the construction sector uses 50% of the Earth's raw materials and produces 50% of its waste, the development of more durable and sustainable building materials is crucial. Today, Construction and Demolition Waste (CDW) is mainly used in low level applications, namely as unbound material for foundations, e.g., in road construction. Mineral demolition waste can be recycled as crushed aggregates for concrete, but these reduce the compressive strength and affect the workability due to higher values of water absorption. To advance the use of concrete rubble, Completely Recyclable Concrete (CRC) is designed for reincarnation within the cement production, following the Cradle-to-Cradle (C2C) principle. By the design, CRC becomes a resource for cement production because the chemical composition of CRC will be similar to that of cement raw materials. If CRC is used on a regular basis, a closed concrete-cement-concrete material cycle will arise, which is completely different from the current life cycle of traditional concrete. Within the research towards this CRC it is important to quantify the benefit for the environment and Life Cycle Assessment (LCA) needs to be performed, of which the results are presented in a this paper. It was observed that CRC could significantly reduce the global warming potential of concrete.

  14. Life Cycle Assessment of Completely Recyclable Concrete

    Directory of Open Access Journals (Sweden)

    Mieke De Schepper

    2014-08-01

    Full Text Available Since the construction sector uses 50% of the Earth’s raw materials and produces 50% of its waste, the development of more durable and sustainable building materials is crucial. Today, Construction and Demolition Waste (CDW is mainly used in low level applications, namely as unbound material for foundations, e.g., in road construction. Mineral demolition waste can be recycled as crushed aggregates for concrete, but these reduce the compressive strength and affect the workability due to higher values of water absorption. To advance the use of concrete rubble, Completely Recyclable Concrete (CRC is designed for reincarnation within the cement production, following the Cradle-to-Cradle (C2C principle. By the design, CRC becomes a resource for cement production because the chemical composition of CRC will be similar to that of cement raw materials. If CRC is used on a regular basis, a closed concrete-cement-concrete material cycle will arise, which is completely different from the current life cycle of traditional concrete. Within the research towards this CRC it is important to quantify the benefit for the environment and Life Cycle Assessment (LCA needs to be performed, of which the results are presented in a this paper. It was observed that CRC could significantly reduce the global warming potential of concrete.

  15. Blood-brain barrier to peptides: (/sup 3/H)gonadotropin-releasing hormone accumulation by eighteen regions of the rat brain and by anterior pituitary

    Energy Technology Data Exchange (ETDEWEB)

    Ermisch, A.; Ruehle, H.J. (Karl-Marx-Universitaet, Leipzig (German Democratic Republic). Sektion Biowissenschaften); Klauschenz, E.; Kretzschmar, R. (Akademie der Wissenschaften der DDR, Berlin. Inst. fuer Wirkstofforschung)

    1984-01-01

    After intracarotid injection of (/sup 3/H)gonadotropin-releasing hormone ((/sup 3/H)GnRH) the mean accumulation of radioactivity per unit wet weight of 18 brain samples investigated and the anterior pituitary was 0.38 +- 0.11% g/sup -1/ of the injected tracer dose. This indicates a low but measurable brain uptake of the peptide. The brain uptake of (/sup 3/H)GnRH in blood-brain barrier (BBB)-protected regions is 5% of that of separately investigated (/sup 3/H)OH. In BBB-free regions the accumulation of radioactivity was more than 25-fold higher than in BBB-protected regions. The accumulation of (/sup 3/H)GnRH among regions with BBB varies less than among regions with leaky endothelia. The data presented for (/sup 3/H)GnRH are similar to those for other peptides so far investigated.

  16. Gonadotropin-releasing hormone (Gn-RH) in striped mullet (Mugil cephalus), milkfish (Chanos chanos), and rainbow trout (Salmo gairdneri): comparison with salmon Gn-RH

    Energy Technology Data Exchange (ETDEWEB)

    Sherwood, N.M.; Harvey, B.; Brownstein, M.J.; Eiden, L.E.

    1984-08-01

    Immunoreactive gonadotropin-releasing hormone (Gn-RH) was extracted from brains of striped mullet, milkfish, rainbow trout, and chum salmon with acetone/HCl and petroleum ether. High pressure liquid chromatography and cross-reactivity studies show mullet, milkfish, and trout brains to contain a peptide chromatographically and immunologically identical to synthetic salmon Gn-RH, while the mammalian form of Gn-RH is detectable in none of these fishes. Gn-RH is present in immature 7-month-old and 4-year-old milkfish. A second immunoreactive peptide is separable by HPLC in all the fish studied. This early-eluting form of Gn-RH is unlikely to be a precursor; its cross-reactivity with antisera R-42 and number185 suggests that any modification is in the C-terminal region. Several possible roles for this peptide are advanced.

  17. Gonadotropin-Releasing Hormone Analog Cotreatment for the Preservation of Ovarian Function during Gonadotoxic Chemotherapy for Breast Cancer: A Meta-Analysis.

    Directory of Open Access Journals (Sweden)

    Chuan Wang

    Full Text Available To determine by meta-analysis whether gonadotropin-releasing hormone analog (GnRHa cotreatment accompanying chemotherapy for breast cancer protects ovarian function.Randomized controlled trials (RCTs comparing GnRH cotreatment with chemotherapy alone in premenopausal women were collected by electronic and manual searches of Pubmed, MEDLINE (OVID, CENTRAL (The Coehrane Central Register of Controlled Trials, CBM, CNKI, VIP and Wanfang data bases. All the data was analyzed by Stata 11.2.Seven studies with a total of 677 participants met the inclusion criteria. The outcome of meta-analysis implied that, compared with adjuvant chemotherapy alone, the number of patients with resumption of spontaneous menstruation was statistically greater in the GnRH cotreatment patients (OR 2.83; 95% CI, 1.52-5.25.Evidence from RCTs suggests a potential benefit of GnRH cotreatment with chemotherapy in premenopausal women, producing higher rates of spontaneous resumption of menses.

  18. Detection of Messenger RNA for Gonadotropin-Releasing Hormone (GnRH) but not for GnRH Receptors in Rat Pancreas

    Institute of Scientific and Technical Information of China (English)

    王雷; 谢莉萍; 黄威权; 张荣庆

    2001-01-01

    Although gonadotropin-releasing hormone (GnRH), GnRH-like molecule, and GnRH receptor (GnRH-R) have been reported to exist in several tissues other than brain or anterior pituitary, there are no reports concerning GnRH or GnRH-R gene expression in a normal pancreatic gland. In order to define the production of GnRH as well as GnRH-R in the pancreatic gland, we examined their gene expression in various developmental stages of rat pancreas using the reverse transcriptase-polymerase chain reaction (RT-PCR).GnRH mRNA transcripts were found in pancreas of male and female rats at different ages, expressing at about the same level, whereas GnRH-R mRNA transcripts could not be detected in any rat pancreatic gland samples. These results suggest a possible biological role of GnRH in rodent pancreas.

  19. Development and Actuality of Life Cycle Cost Technique in China

    Institute of Scientific and Technical Information of China (English)

    GENG Jun-bao; JIN Jia-shan; LUO Yun; WU Yi-liang

    2012-01-01

    Life cycle cost technique is a powerful tool to make a scientific decision and a useful method of advancing the continuable development of the society. In this paper, development course, application actuality and up-to-date research trends of life cycle cost technique in China are summarized. Some suggestions are given on how to general- ize the application of life cycle cost technique which are used as the reference to study life cycle cost technique.

  20. Chain modeling for life cycle systems engineering

    Energy Technology Data Exchange (ETDEWEB)

    Rivera, J.J. [Sandia National Lab., Albuquerque, NM (United States); Shapiro, V. [Univ. of Wisconsin, Madison, WI (United States). Spatial Automation Lab.

    1997-12-01

    Throughout Sandia`s history, products have been represented by drawings. Solid modeling systems have recently replaced drawings as the preferred means for representing product geometry. These systems are used for product visualization, engineering analysis and manufacturing planning. Unfortunately, solid modeling technology is inadequate for life cycle systems engineering, which requires maintenance of technical history, efficient management of geometric and non-geometric data, and explicit representation of engineering and manufacturing characteristics. Such information is not part of the mathematical foundation of solid modeling. The current state-of-the-art in life cycle engineering is comprised of painstakingly created special purpose tools, which often are incompatible. New research on {open_quotes}chain modeling{close_quotes} provides a method of chaining the functionality of a part to the geometric representation. Chain modeling extends classical solid modeling to include physical, manufacturing, and procedural information required for life cycle engineering. In addition, chain modeling promises to provide the missing theoretical basis for Sandia`s parent/child product realization paradigm. In chain modeling, artifacts and systems are characterized in terms of their combinatorial properties: cell complexes, chains, and their operators. This approach is firmly rooted in algebraic topology and is a natural extension of current technology. The potential benefits of this approach include explicit hierarchical and combinatorial representation of physics, geometry, functionality, test, and legacy data in a common computational framework that supports a rational decision process and partial design automation. Chain modeling will have a significant impact on design preservation, system identification, parameterization, system reliability, and design simplification.

  1. Battery life-cycle cost analysis

    Energy Technology Data Exchange (ETDEWEB)

    Brown, D.R.; Humphreys, K.K.

    1988-07-01

    Life-cycle cost (LCC) estimates have been prepared for 17 combinations of battery or fuel-cell technologies and load-levelling, stand-alone power system, or electric vehicle applications. In addition, LCCs for gas-fired turbine, compressed-air energy storage, pumped hydro energy storage, and internal combustion engine technologies were estimated for comparative purposes. The objectives in preparing the estimates were to determine the relative economics among alternative battery systems and to compare battery systems economics with competing energy technologies.

  2. Aquatic ecotoxicological indicators in life cycle assessment

    DEFF Research Database (Denmark)

    Pennington, David W.; Payet, Jerome; Hauschild, Michael Zwicky

    2004-01-01

    This paper compares available options for the aquatic ecotoxicological effect factor component in life cycle assessment (LCA). The effect factor is expressed here as the change in risk per unit change in cumulative exposure, ƒ´Effect/ƒ´Exposure. The comparison is restricted to approaches linked...... mixtures (ms), ƒ´C is the change in cumulative exposure concentration of the chemical of interest, and HC50 is the median, chronic Hazardous Concentration for regional, multiple species systems. The resultant aquatic effect factors are risk-based and can be readily estimated for many chemicals using...

  3. Publication Life Cycle at CERN Document Server

    CERN Multimedia

    Witowski, Sebastian; Costa, Flavio; Gabancho, Esteban; Marian, Ludmila; Tzovanakis, Harris

    2017-01-01

    This presentation guides listeners through all the stages of publication life cycle at CERN Document Server, from the ingestion using one of the various tools, through curation and processing, until the data is ready to be exported to other systems. It describes different tools that we are using to curate the incoming publications as well as to further improve the existing data on CDS. The second part of the talk goes through various challenges we have faced in the past and how we are going to overcome them in the new version of CDS.

  4. Life Cycle Assessment of Wall Systems

    Science.gov (United States)

    Ramachandran, Sriranjani

    Natural resource depletion and environmental degradation are the stark realities of the times we live in. As awareness about these issues increases globally, industries and businesses are becoming interested in understanding and minimizing the ecological footprints of their activities. Evaluating the environmental impacts of products and processes has become a key issue, and the first step towards addressing and eventually curbing climate change. Additionally, companies are finding it beneficial and are interested in going beyond compliance using pollution prevention strategies and environmental management systems to improve their environmental performance. Life-cycle Assessment (LCA) is an evaluative method to assess the environmental impacts associated with a products' life-cycle from cradle-to-grave (i.e. from raw material extraction through to material processing, manufacturing, distribution, use, repair and maintenance, and finally, disposal or recycling). This study focuses on evaluating building envelopes on the basis of their life-cycle analysis. In order to facilitate this analysis, a small-scale office building, the University Services Building (USB), with a built-up area of 148,101 ft2 situated on ASU campus in Tempe, Arizona was studied. The building's exterior envelope is the highlight of this study. The current exterior envelope is made of tilt-up concrete construction, a type of construction in which the concrete elements are constructed horizontally and tilted up, after they are cured, using cranes and are braced until other structural elements are secured. This building envelope is compared to five other building envelope systems (i.e. concrete block, insulated concrete form, cast-in-place concrete, steel studs and curtain wall constructions) evaluating them on the basis of least environmental impact. The research methodology involved developing energy models, simulating them and generating changes in energy consumption due to the above mentioned

  5. Geothermal life cycle assessment - part 3

    Energy Technology Data Exchange (ETDEWEB)

    Sullivan, J. L. [Argonne National Lab. (ANL), Argonne, IL (United States); Frank, E. D. [Argonne National Lab. (ANL), Argonne, IL (United States); Han, J. [Argonne National Lab. (ANL), Argonne, IL (United States); Elgowainy, A. [Argonne National Lab. (ANL), Argonne, IL (United States); Wang, M. Q. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2013-11-01

    A set of key issues pertaining to the environmental performance of geothermal electric power have been addressed. They include: 1) greenhouse gas emissions (GHG) from geothermal facilities, 2) the use of supercritical carbon dioxide (scCO2) as a geofluid for enhanced geothermal systems (EGS), 3) quantifying the impact of well field exploration on the life cycle of geothermal power, and finally 4) criteria pollutant emissions for geothermal and other electric power generation. A GHG emission rate (g/kWh) distribution as function of cumulative running capacity for California has been developed based on California and U. S. government data. The distribution is similar to a global distribution for compared geothermal technologies. A model has been developed to estimate life cycle energy of and CO2 emissions from a coupled pair of coal and EGS plants, the latter of which is powered by scCO2 captured from coal plant side. Depending on the CO2 capture rate on the coal side and the CO2 consumption rate on the EGS side, significant reductions in GHG emissions were computed when the combined system is compared to its conventional coal counterpart. In effect, EGS CO2 consumption acts as a sequestration mechanism for the coal plant. The effects CO2 emissions from the coupled system, prompt on the coal side and reservoir leakage on the EGS side, were considered as well as the subsequent decline of these emissions after entering the atmosphere over a time frame of 100 years. A model was also developed to provide better estimates of the impact of well field exploration on the life cycle performance of geothermal power production. The new estimates increase the overall life cycle metrics for the geothermal systems over those previously estimated. Finally, the GREET model has been updated to include the most recent criteria pollutant emissions for a range of renewable (including geothermal) and other power

  6. Life cycle assessment of shredder residue management

    DEFF Research Database (Denmark)

    Boldrin, Alessio; Damgaard, Anders; Brogaard, Line Kai-Sørensen

    This report provides a life-cycle assessment (LCA) of the treatment of shredder residue (SR) in Denmark. The LCA was conducted for the Environmental Protection Agency by DTU Environment in the period March-July 2014, as part of a service agreement between the Danish Environmental Protection Agency...... wood waste, wood waste for recycling and district heating pipes. The LCA was conducted using the EASETECH LCA model developed by DTU Environment for the environmental assessment of waste management systems and environmental technologies. The LCA was conducted in accordance with the LCA principles...

  7. Oil Points - Life Cycle Evaluations without the Data Problem

    DEFF Research Database (Denmark)

    Bey, Niki; Lenau, Torben Anker; Larsen, Michael Holm

    1999-01-01

    Environmental aspects of products in their whole life cycle are of increasing importance in industry [1]. Therefore, several methods and tools for environmental life cycle evaluation have been developed during the last years. Formal Life Cycle Assessment (LCA), the state-of-the-art in environment...

  8. Overnight Levels of Luteinizing Hormone, Follicle-Stimulating Hormone and Growth Hormone before and during Gonadotropin-Releasing Hormone Analogue Treatment in Short Boys Born Small for Gestational Age

    NARCIS (Netherlands)

    van der Kaay, Danielle C. M.; de Jong, Frank H.; Rose, Susan R.; Odink, Roelof J. H.; Bakker-van Waarde, Willie M.; Sulkers, Eric J.; Hokken-Koelega, Anita C. S.

    2009-01-01

    Aims: To evaluate if 3 months of gonadotropin-releasing hormone analogue (GnRHa) treatment results in sufficient suppression of pubertal luteinizing hormone (LH) and follicle-stimulating hormone (FSH) profile patterns in short pubertal small for gestational age (SGA) boys. To compare growth hormone

  9. Overnight levels of luteinizing hormone, follicle-stimulating hormone and growth hormone before and during gonadotropin-releasing hormone analogue treatment in short boys born small for gestational age

    NARCIS (Netherlands)

    D.C.M. van der Kaay (Danielle); F.H. de Jong (Frank); S.R. Rose (Susan); R.J.H. Odink (Roelof); W.M. Bakker-Van Waarde (Willie); E.J. Sulkers (Eric); A.C.S. Hokken-Koelega (Anita)

    2009-01-01

    textabstractAims: To evaluate if 3 months of gonadotropin-releasing hormone analogue (GnRHa) treatment results in sufficient suppression of pubertal luteinizing hormone (LH) and follicle-stimulating hormone (FSH) profile patterns in short pubertal small for gestational age (SGA) boys. To compare gro

  10. Life cycle responses to health insurance status.

    Science.gov (United States)

    Pelgrin, Florian; St-Amour, Pascal

    2016-09-01

    This paper studies the lifetime effects of exogenous changes in health insurance coverage (e.g. Medicare, PPACA, termination of employer-provided plans) on the dynamic optimal allocation (consumption, leisure, health expenditures), status (health and wealth), and welfare. We solve, simulate, and structurally estimate a parsimonious life cycle model with endogenous exposure to morbidity and mortality risks, and exogenous health insurance. By varying coverage, we identify the marginal effects of insurance when young and/or when old on allocations, statuses, and welfare. Our results highlight positive effects of insurance on health, wealth and welfare, as well as mid-life substitution away from healthy leisure in favor of more health expenses, caused by peaking wages, and accelerating health issues.

  11. Evolution of Life Cycles in Early Amphibians

    Science.gov (United States)

    Schoch, Rainer R.

    2009-05-01

    Many modern amphibians have biphasic life cycles with aquatic larvae and terrestrial adults. The central questions are how and when this complicated ontogeny was established, and what is known about the lives of amphibians in the Paleozoic. Fossil evidence has accumulated that sheds light on the life histories of early amphibians, the origin of metamorphosis, and the transition to a fully terrestrial existence. The majority of early amphibians were aquatic or amphibious and underwent only gradual ontogenetic changes. Developmental plasticity played a major role in some taxa but was restricted to minor modification of ontogeny. In the Permo-Carboniferous dissorophoids, a condensation of crucial ontogenetic steps into a short phase (metamorphosis) is observed. It is likely that the origin of both metamorphosis and neoteny falls within these taxa. Fossil evidence also reveals the sequence of evolutionary changes: apparently, the ontogenetic change in feeding, not the transition to a terrestrial existence per se, made a drastic metamorphosis necessary.

  12. Life cycle assessment of emerging technologies

    DEFF Research Database (Denmark)

    Valsasina, Lucia; Pizzol, Massimo; Smetana, Sergiy;

    2017-01-01

    Abstract Milk is becoming a key food commodity as population grows and demand increases. The treatment of milk to extend its shelf life is thus an important step in avoiding losses and optimizing resource use. The drawbacks of the most common treatments for shelf stable milk are the loss of nutri......Abstract Milk is becoming a key food commodity as population grows and demand increases. The treatment of milk to extend its shelf life is thus an important step in avoiding losses and optimizing resource use. The drawbacks of the most common treatments for shelf stable milk are the loss...... shelf life. A life cycle assessment was performed comparing this emerging technology to the common thermal treatment: indirect ultra-high temperature sterilisation combined with non-aseptic homogenisation. The results show that high-pressure based processing has a lower environmental burden compared...... to the high-temperature based processing, already at pilot-scale, and this difference is primarily due to the lower electricity consumption. Additionally, upscaling considerations were made using power laws and scenario analysis to simulate future full-scale applications of UHPH. The upscaling shows...

  13. Combining life cycle costing and life cycle assessment for an analysis of a new residential district energy system design

    OpenAIRE

    Ristimäki, Miro; Säynäjoki, Antti; Heinonen, Jukka; Junnila, Seppo

    2013-01-01

    Due to the growing threat of climate change, we are challenged to find improved assessment practises to recognize solutions for sustainable urban development. The focus of the study is on the life cycle design of a district energy system for a new residential development in Finland. This study analyses LCC (life cycle costs) and carbon emissions (LCA (life cycle assessment)), i.e., the “viability” of different energy systems through a methodological life cycle framework. By combining LCC and ...

  14. Developing Asset Life Cycle Management capabilities through the implementation of Asset Life Cycle Plans – an Action Research project

    NARCIS (Netherlands)

    Ruitenburg, Richard; Braaksma, Anne Johannes Jan

    2017-01-01

    Asset Life Cycle Management is a strategic approach to managing physical assets over their complete life cycle. However, the literature and the recent ISO 55,000 standard do not offer guidance as to how to develop such an approach. This paper investigates the main capabilities for Asset Life Cycle

  15. Early gonadotropin-releasing hormone antagonist start improves follicular synchronization and pregnancy outcome as compared to the conventional antagonist protocol.

    Science.gov (United States)

    Park, Chan Woo; Hwang, Yu Im; Koo, Hwa Seon; Kang, Inn Soo; Yang, Kwang Moon; Song, In Ok

    2014-12-01

    To assess whether an early GnRH antagonist start leads to better follicular synchronization and an improved clinical pregnancy rate (CPR). A retrospective cohort study. A total of 218 infertile women who underwent IVF between January 2011 and February 2013. The initial cohort (Cohort I) that underwent IVF between January 2011 and March 2012 included a total of 68 attempted IVF cycles. Thirty-four cycles were treated with the conventional GnRH antagonist protocol, and 34 cycles with an early GnRH antagonist start protocol. The second cohort (Cohort II) that underwent IVF between June 2012 and February 2013 included a total of 150 embryo-transfer (ET) cycles. Forty-three cycles were treated with the conventional GnRH antagonist protocol, 34 cycles with the modified early GnRH antagonist start protocol using highly purified human menopause gonadotropin and an addition of GnRH agonist to the luteal phase support, and 73 cycles with the GnRH agonist long protocol. The analysis of Cohort I showed that the number of mature oocytes retrieved was significantly higher in the early GnRH antagonist start cycles than in the conventional antagonist cycles (11.9 vs. 8.2, p=0.04). The analysis of Cohort II revealed higher but non-significant CPR/ET in the modified early GnRH antagonist start cycles (41.2%) than in the conventional antagonist cycles (30.2%), which was comparable to that of the GnRH agonist long protocol cycles (39.7%). The modified early antagonist start protocol may improve the mature oocyte yield, possibly via enhanced follicular synchronization, while resulting in superior CPR as compared to the conventional antagonist protocol, which needs to be studied further in prospective randomized controlled trials.

  16. Life Cycle Assessment of Sugar Production (VB)

    DEFF Research Database (Denmark)

    Teljigovic, Mehmed; Mengiardi, Jon; Factor, Gabriela

    1999-01-01

    The environmental organisation NOAH has proposed carrying out an environmental assessment of two different sugar productions (using sugar beet or sugar cane) in order to illustrate which of the systems has a higher environmental impact for sugar consumption in Denmark. Therefore a comparison...... will be made between sugar from sugar beet produced in Denmark versus sugar produces from sugar cane in a tropical country, Brazil, and transported afterwards to Denmark. To evaluate the environmental aspects of these two product systems a Life Cycle Assessement (LCA) will be carried out.From the results...... obtained in the present LCA of sugar produces from sugar canes or sugar beet it is difficult to make an immediate choice between the two possibilities. Indeed, Quantitative results from the EDIP (Environmental Design of Industrial Products) software are globally similar for both ways of producing sugar...

  17. Life cycle test of the NOXSO process

    Energy Technology Data Exchange (ETDEWEB)

    Ma, W.T.; Haslbeck, J.L.; Neal, L.G.

    1990-05-01

    This paper summarizes the data generated by the NOXSO Life Cycle Test Unit (LCTU). The NOXSO process is a dry flue gas treatment system that employs a reusable sorbent. The sorbent consists of sodium carbonate impregnated on a high-surface-area gamma alumina. A fluidized bed of sorbent simultaneously removes SO{sub 2} and NO{sub x} from flue gas at a temperature of 250{degrees}F. The spent sorbent is regenerated for reuse by treatment at high temperature with a reducing gas. This regeneration reduces sorbed sulfur compounds to SO{sub 2}, H{sub 2}S, and elemental sulfur. The SO{sub 2} and H{sub 2}S are then converted to elemental sulfur in a Claus-type reactor. The sulfur produced is a marketable by-product of the process. Absorbed nitrogen oxides are decomposed and evolved on heating the sorbent to regeneration temperature.

  18. PROJECT GOVERNANCE – PHASES AND LIFE CYCLE

    Directory of Open Access Journals (Sweden)

    Robbert Titus DEENEN

    2007-01-01

    Full Text Available When talking about projects, the barrier is clear: successful and failed. Some fail due to different reasons, but lack of good project and risk management played a large part. Others succeed largely because of the rigorous and disciplined application of good project practices. But both groups illustrate many points that underline and demonstrate important concepts applicable to current projects. Systematic application of good methods leads to successful outcomes in projects of all types. All projects are fundamentally dependent on people, and human beings are not very different today than we were hundreds, or even thousands, of years ago. This paper uncovers main elements in projects area such as the concepts and governance of projects, with an underline of the main characteristics and the projects phases and life cycle that erase the uncertainty that joins all the projects built at any time.

  19. Life Cycle Assessment of Electricity Systems

    DEFF Research Database (Denmark)

    Turconi, Roberto

    a systematic framework for the life cycle assessment (LCA) of electricity systems, which aimed at providing: •Scientifically sound recommendations for decision-making processes, leading to more sustainable energy systems; •Accurate and transparent LCA data for electricity supply, thereby increasing......Electricity systems represent a major source of global pollutants. Whilst currently relying heavily on fossil fuels, electricity systems are progressively shifting towards renewable sources to mitigate climate change and enhance energy security. The goal of this PhD project was to develop...... developing data on smart grids should be a priority for future research. The environmental impacts of low-carbon electricity systems were assessed by combining LCA with power system modelling. Possible scenarios for the island of Ireland in 2025 and Denmark in 2030, with high amounts of wind power, were...

  20. 20th CIRP International Conference on Life Cycle Engineering

    CERN Document Server

    Song, Bin; Ong, Soh-Khim

    2013-01-01

    This edited volume presents the proceedings of the 20th CIRP LCE Conference, which cover various areas in life cycle engineering such as life cycle design, end-of-life management, manufacturing processes, manufacturing systems, methods and tools for sustainability, social sustainability, supply chain management, remanufacturing, etc.

  1. Effects of early vaccination with a gonadotropin releasing factor analog-diphtheria toxoid conjugate on boar taint and growth performance of male pigs.

    Science.gov (United States)

    Kantas, D; Papatsiros, V; Tassis, P; Tzika, E; Pearce, M C; Wilson, S

    2014-05-01

    The aim of this study was to evaluate safety (in terms of detecting possible adverse clinical effects attributable to vaccination), efficacy, and effects on growth performance of a gonadotropin releasing factor analog-diphtheria toxoid conjugate (commercially distributed as Improvac; Zoetis, Zaventem, Belgium) in male pigs raised in a commercial Greek farm. A total of 1,230 male pigs was enrolled in 16 weekly batches and allocated to 3 groups: barrows (castrated on the next day after birth [study Day 0]), pigs vaccinated with the above-mentioned product, and intact boars. Vaccinated pigs were injected subcutaneously with 2 mL of the anti-gonadotropin releasing factor (GnRF) vaccine at 9 to 11 wk of age (60-78 d) and 15 to 17 wk of age (102-120 d) and slaughtered at 22 to 25 wk of age (152-176 d). No clinical abnormalities or adverse events attributable to vaccination occurred. Mean BW of vaccinated pigs was 6% greater compared with barrows at slaughter (P vaccinated pigs had greater ADG than barrows from castration to slaughter (8%). In detail, a lower ADG from first to second vaccination (-12%; P vaccination to slaughter (P vaccinated pigs and intact boars was not significantly different throughout the study, except from first to second vaccination (boars greater; P = 0.0059) and second vaccination to slaughter (vaccinates greater; P = 0.0390). Feed conversion ratio of barrows was 11 and 8% greater compared with vaccinated pigs (P = 0.0005) and boars (P = 0.0062) from first to second vaccination but was 23 to 26% lower compared with vaccinated pigs (P vaccination to slaughter and 7 to 9.5% lower from the second vaccination to slaughter (P = 0.0029 and P = 0.0003 for vaccinates and intact boars, respectively). At slaughter, the belly fat androstenone concentration of all vaccinated pigs and 64% of intact boars was below 200 ng/g. Belly fat skatole concentration was below 20 ng/g in samples from all groups. In conclusion, vaccination against GnRF using the Gn

  2. Is the effect of premature elevated progesterone augmented by human chorionic gonadotropin versus gonadotropin-releasing hormone agonist trigger?

    Science.gov (United States)

    Connell, Matthew T; Patounakis, George; Healy, Mae Wu; DeCherney, Alan H; Devine, Kate; Widra, Eric; Levy, Michael J; Hill, Micah J

    2016-09-01

    To compare the effect of P on live birth rate between hCG and GnRH agonist (GnRH-a) trigger cycles. Retrospective cohort study. Large private assisted reproductive technology (ART) practice. A total of 3,326 fresh autologous ART cycles. None. Live birth. A total of 647 GnRH-a trigger cycles were compared with 2,679 hCG trigger cycles. Live birth was negatively associated with P in both the hCG trigger (odds ratio [OR] 0.62, 95% confidence interval [CI] 0.52-0.76) and the agonist trigger cohorts (OR 0.56, 95% CI 0.45-0.69). Interaction testing evaluating P and trigger medication was not significant, indicating that P had a similar negative effect on live birth rates in both cohorts. Progesterone ≥2 ng/mL occurred more commonly in GnRH-a trigger cycles compared with hCG trigger cycles (5.5% vs. 3.1%) and was negatively associated with live birth in both the hCG trigger (OR 0.28, 95% CI 0.11-0.73) and agonist trigger cohorts (OR 0.35, 95% CI 0.14-0.90). When P ≥2 ng/mL, the live birth rates were poor and similar in the hCG and GnRH-a cohorts (5.9% vs. 14.2%), indicating that P ≥2 ng/mL had a similar negative effect on live birth in both cohorts. Elevated serum P on the day of hCG was negatively associated with live birth rates in both hCG and GnRH-a trigger cycles. Published by Elsevier Inc.

  3. Estimating pesticide emissions for life cycle assessment of agricultural products

    DEFF Research Database (Denmark)

    Hauschild, Michael Zwicky; Røpke, Inge

    2004-01-01

    As the first country in Europe Denmark almost 2 years ago established an official center for Life Cycle Assessments and life cycle approaches as an element of the national IPP (Integrated Product Policy). The Danish EPA lends financial support to this important initiative, the aim of which is to:...... evaluation finished in September 2004. Important learnings for all who are engaged in dissemination of life cycle thinking in industry will be presented....

  4. 10 CFR 455.64 - Life-cycle cost methodology.

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 3 2010-01-01 2010-01-01 false Life-cycle cost methodology. 455.64 Section 455.64 Energy..., Hospitals, Units of Local Government, and Public Care Institutions § 455.64 Life-cycle cost methodology. (a) The life-cycle cost methodology under § 455.63(b) of this part is a systematic comparison of the...

  5. Life Cycle Design - a Route to the Sustainable Industrial Culture?

    DEFF Research Database (Denmark)

    Hauschild, Michael Zwicky; Wenzel, Henrik; Alting, Leo

    1999-01-01

    In the attempt to reorient Society's development in a more sustainable direction attention is focused on the environmental impact of products and systems over their entire life cycle, but how can the environmental life cycle perspective be introduced into the design of new solutions and how much...... is reviewed and the overall question of to what extent life cycle design is a route to the sustainable industrial culture is discussed....

  6. Mainstreaming life cycle thinking through a consistent approach to footprints

    DEFF Research Database (Denmark)

    Ridoutt, Brad; Pfister, Stephan; Manzardo, Alessandro

    2016-01-01

    the auspices of the UNEP/SETAC Life Cycle Initiative project on environmental Life Cycle Impact Assessment has been working to develop generic guidance for developers of footprint metrics. The initial work involved forming a consensual position on the difference between footprints and existing LCA impact......-alone and not part of a framework intended for comprehensive environmental performance assessment. Accordingly, footprints are universally defined as metrics used to report life cycle assessment results addressing an Area of Concern....

  7. Household Life Cycle: The Case Of Customer Satisfaction In Restaurants

    National Research Council Canada - National Science Library

    Cindy Erdis; Michael du Toit

    2014-01-01

    ... on customer satisfaction in restaurants. This article examines the influence of household life cycle on customer satisfaction in selected restaurants in the Tshwane area of Gauteng, South Africa...

  8. Life Cycle Engineering – from methodology to enterprise culture

    DEFF Research Database (Denmark)

    Hauschild, Michael Zwicky; Alting, Leo; Poll, Christian

    2003-01-01

    As part of a sustainable development, the environmental efficiency of industry must increase by a factor four to ten. This engenders attention to the environmental impact of products and technical systems over their entire life cycle. The last decade has seen the development of a number...... of methodologies and tools for life cycle assessment and development of more eco-efficient products, from complex to simplified, catering to the needs of especially small and medium-sized enterprizes. The tools and data are in place, but dissemination lacks behind. Propagation of life cycle thinking and life cycle...

  9. Life Cycle Design - a Route to the Sustainable Industrial Culture?

    DEFF Research Database (Denmark)

    Hauschild, Michael Zwicky; Wenzel, Henrik; Alting, Leo

    1999-01-01

    In the attempt to reorient Society's development in a more sustainable direction attention is focused on the environmental impact of products and systems over their entire life cycle, but how can the environmental life cycle perspective be introduced into the design of new solutions and how much...... can be optained through life cycle design? The authors' experience with integration of environmental considerations in product development is presented, ranging from the detailed interactive approach to the EDIP-method through various simplified approaches. The potential for environmental improvements...... is reviewed and the overall question of to what extent life cycle design is a route to the sustainable industrial culture is discussed....

  10. Anterior Pituitary Leptin Expression Changes in Different Reproductive States: Stimulation, in vitro, by Gonadotropin Releasing Hormone (GnRH)

    OpenAIRE

    Akhter, Noor; Johnson, Brandy W.; Crane, Christopher; Iruthayanathan, Mary; Zhou, Yi-Hong; Kudo, Akihiko; Childs, Gwen V.

    2006-01-01

    This study was designed to learn more about the changes in expression of rat anterior pituitary (AP) leptin during the estrous cycle. QRT-PCR assays of cycling rat AP leptin mRNA showed 2—fold increases from metestrus to diestrus followed by an 86% decrease on the morning of proestrus. Percentages of leptin cells increased in proestrus and pregnancy to 55–60% of AP cells. Dual labeling for leptin proteins and growth hormone (GH) or gonadotropins, showed that the rise in leptin protein-bearing...

  11. The Life-cycle of Operons

    Energy Technology Data Exchange (ETDEWEB)

    Price, Morgan N.; Arkin, Adam P.; Alm, Eric J.

    2007-03-15

    Operons are a major feature of all prokaryotic genomes, buthow and why operon structures vary is not well understood. To elucidatethe life-cycle of operons, we compared gene order between Escherichiacoli K12 and its relatives and identified the recently formed anddestroyed operons in E. coli. This allowed us to determine how operonsform, how they become closely spaced, and how they die. Our findingssuggest that operon evolution may be driven by selection on geneexpression patterns. First, both operon creation and operon destructionlead to large changes in gene expression patterns. For example, theremoval of lysA and ruvA from ancestral operons that contained essentialgenes allowed their expression to respond to lysine levels and DNAdamage, respectively. Second, some operons have undergone acceleratedevolution, with multiple new genes being added during a brief period.Third, although genes within operons are usually closely spaced becauseof a neutral bias toward deletion and because of selection against largeoverlaps, genes in highly expressed operons tend to be widely spacedbecause of regulatory fine-tuning by intervening sequences. Althoughoperon evolution may be adaptive, it need not be optimal: new operonsoften comprise functionally unrelated genes that were already inproximity before the operon formed.

  12. The principles of life-cycle analysis

    Energy Technology Data Exchange (ETDEWEB)

    Hill, L.J.; Hunsaker, D.B.; Curlee, T.R.

    1996-05-01

    Decisionmakers representing government agencies must balance competing objectives when deciding on the purchase and sale of assets. The goal in all cases should be to make prudent or financially {open_quotes}cost-effective{close_quotes} decisions. That is, the revenues from the purchase or sale of assets should exceed any out-of-pocket costs to obtain the revenues. However, effects external to these financial considerations such as promoting environmental quality, creating or maintaining jobs, and abiding by existing regulations should also be considered in the decisionmaking process. In this paper, we outline the principles of life-cycle analysis (LCA), a framework that allows decisionmakers to make informed, balanced choices over the period of time affected by the decision, taking into account important external effects. Specifically, LCA contains three levels of analysis for any option: (1) direct financial benefits (revenues) and out-of-pocket costs for a course of action; (2) environmental and health consequences of a decision; and (3) other economic and socio-institutional effects. Because some of the components of LCA are difficult to value in monetary terms, the outcome of the LCA process is not generally a yes-no answer. However, the framework allows the decisionmaker to at least qualitatively consider all relevant factors in analyzing options, promoting sound decisionmaking in the process.

  13. The Life-cycle of Operons

    Energy Technology Data Exchange (ETDEWEB)

    Price, Morgan N.; Arkin, Adam P.; Alm, Eric J.

    2005-11-18

    Operons are a major feature of all prokaryotic genomes, but how and why operon structures vary is not well understood. To elucidate the life-cycle of operons, we compared gene order between Escherichia coli K12 and its relatives and identified the recently formed and destroyed operons in E. coli. This allowed us to determine how operons form, how they become closely spaced, and how they die. Our findings suggest that operon evolution is driven by selection on gene expression patterns. First, both operon creation and operon destruction lead to large changes in gene expression patterns. For example, the removal of lysA and ruvA from ancestral operons that contained essential genes allowed their expression to respond to lysine levels and DNA damage, respectively. Second, some operons have undergone accelerated evolution, with multiple new genes being added during a brief period. Third, although most operons are closely spaced because of a neutral bias towards deletion and because of selection against large overlaps, highly expressed operons tend to be widely spaced because of regulatory fine-tuning by intervening sequences. Although operon evolution seems to be adaptive, it need not be optimal: new operons often comprise functionally unrelated genes that were already in proximity before the operon formed.

  14. Antimullerian hormone: prediction of cumulative live birth in gonadotropin-releasing hormone antagonist treatment for in vitro fertilization

    NARCIS (Netherlands)

    Hamdine, O.; Eijkemans, M.J.; Lentjes, E.G.; Torrance, H.L.; Macklon, N.S.; Fauser, B.C.; Broekmans, F.J.

    2015-01-01

    OBJECTIVE: To assess the accuracy of antimullerian hormone (AMH) in predicting cumulative live birth rate (CLBR) within 1 year after treatment initiation in GnRH antagonist treatment cycles for in vitro fertilization (IVF). DESIGN: Observational (retrospective) substudy as part of an ongoing

  15. Change in body mass index and insulin resistance after 1-year treatment with gonadotropin-releasing hormone agonists in girls with central precocious puberty.

    Science.gov (United States)

    Park, Jina; Kim, Jae Hyun

    2017-03-01

    Gonadotropin-releasing hormone agonist (GnRHa) is used as a therapeutic agent for central precocious puberty (CPP); however, increased obesity may subsequently occur. This study compared body mass index (BMI) and insulin resistance during the first year of GnRHa treatment for CPP. Patient group included 83 girls (aged 7.0-8.9 years) with developed breasts and a peak luteinizing hormone level of ≥5 IU/L after GnRH stimulation. Control group included 48 prepubertal girls. BMI and insulin resistance-related indices (homeostasis model assessment of insulin resistance [HOMA-IR] and quantitative insulin sensitivity check index [QUICKI]) were used to compare the groups before treatment, and among the patient group before and after GnRHa treatment. No statistical difference in BMI z-score was detected between the 2 groups before treatment. Fasting insulin and HOMA-IR were increased in the patient group; fasting glucose-to-insulin ratio and QUICKI were increased in the control group (all Presistance compared to the control group. During GnRHa treatment, normal-weight individuals showed increased BMI z-scores without increased insulin resistance; the overweight group demonstrated increased insulin resistance without significantly altered BMI z-scores. Long-term follow-up of BMI and insulin resistance changes in patients with CPP is required.

  16. Molecular cloning, characterization, and expression analysis of a gonadotropin-releasing hormone-like cDNA in the clam, Ruditapes philippinarum.

    Science.gov (United States)

    Song, Ying; Miao, Jingjing; Cai, Yuefeng; Pan, Luqing

    2015-11-01

    Gonadotropin-releasing hormone (GnRH) is a key neuropeptide regulating reproduction in vertebrates. In the present study, we have cloned and identified the cDNA sequence of the prepro-GnRH (rp-GnRH) in the Manila clam Ruditapes philippinarum. The open reading frame encodes a protein of 94 amino acids, which consists of a signal peptide, a GnRH dodecapeptide, a cleavage site, and a GnRH-associated peptide. These deduced peptides were highly homologous to that reported for other molluscs. We used temperature control to promote gonadal development of the clams. The mRNA expression of rp-GnRH in the visceral ganglia from clams at different reproductive stages was determined by quantitative RT-PCR. The levels of steroids progesterone (P), testosterone (T), and estradiol-17β (E2) in the hemolymph of the corresponding clam were measured by ELISA. The rp-GnRH mRNA was highly expressed at the gonadal early development stage. Concentrations of P, T, and E2 also increased at the early development stage in both sexes. Positive significant correlations between rp-GnRH expression and P content as well as between rp-GnRH expression and T content were observed throughout the gonadal maturation. The results from this study may help to better understand the physiological functions of the native forms of GnRH-like peptides and the actions of GnRH on sex steroids release in bivalve molluscs.

  17. Resurgence of Minimal Stimulation In Vitro Fertilization with A Protocol Consisting of Gonadotropin Releasing Hormone-Agonist Trigger and Vitrified-Thawed Embryo Transfer

    Directory of Open Access Journals (Sweden)

    Zhang John

    2016-07-01

    Full Text Available Minimal stimulation in vitro fertilization (mini-IVF consists of a gentle controlled ovarian stimulation that aims to produce a maximum of five to six oocytes. There is a misbelief that mini-IVF severely compromises pregnancy and live birth rates. An appraisal of the literature pertaining to studies on mini-IVF protocols was performed. The advantages of minimal stimulation protocols are reported here with a focus on the use of clomiphene citrate (CC, gonadotropin releasing hormone (GnRH ago- nist trigger for oocyte maturation, and freeze-all embryo strategy. Literature review and the author’s own center data suggest that minimal ovarian stimulation protocols with GnRH agonist trigger and freeze-all embryo strategy along with single embryo transfer produce a reasonable clinical pregnancy and live birth rates in both good and poor responders. Additionally, mini-IVF offers numerous advantages such as: i. Reduction in cost and stress with fewer office visits, needle sticks, and ultrasounds, and ii. Reduction in the incidence of ovarian hyperstimulation syndrome (OHSS. Mini-IVF is re-emerging as a solution for some of the problems associated with conventional IVF, such as OHSS, cost, and patient discomfort.

  18. Ovulation induction with pulsatile gonadotropin-releasing hormone (GnRH) or gonadotropins in a case of hypothalamic amenorrhea and diabetes insipidus.

    Science.gov (United States)

    Georgopoulos, N A; Markou, K B; Pappas, A P; Protonatariou, A; Vagenakis, G A; Sykiotis, G P; Dimopoulos, P A; Tzingounis, V A

    2001-12-01

    Hypothalamic amenorrhea is a treatable cause of infertility. Our patient was presented with secondary amenorrhea and diabetes insipidus. Cortisol and prolactin responded normally to a combined insulin tolerance test (ITT) and thyrotropin-releasing hormone (TRH) challenge, while thyroid-stimulating hormone (TSH) response to TRH was diminished, and no response of growth hormone to ITT was detected. Both luteinizing hormone (LH) and follicle-stimulating hormone (FSH) levels increased following gonadotropin-releasing hormone (GnRH) challenge. No response of LH to clomiphene citrate challenge was detected. Magnetic resonance imaging findings demonstrated a midline mass occupying the inferior hypothalamus, with posterior lobe not visible and thickened pituitary stalk. Ovulation induction was carried out first with combined human menopausal gonadotropins (hMG/LH/FSH) (150 IU/day) and afterwards with pulsatile GnRH (150 ng/kg/pulse). Ovulation was achieved with both pulsatile GnRH and combine gonadotropin therapy. Slightly better results were achieved with the pulsatile GnRH treatment.

  19. Testicular Dnmt3 expression and global DNA methylation are down-regulated by gonadotropin releasing hormones in the ricefield eel Monopterus albus

    Science.gov (United States)

    Zhang, Yize; Sun, Xin; Zhang, Lihong; Zhang, Weimin

    2017-01-01

    In vertebrates, DNA methyltransferase 3 (Dnmt3) homologues are responsible for de novo DNA methylation and play important roles in germ cell development. In the present study, four dnmt3 genes, dnmt3aa, dnmt3ab, dnmt3ba and dnmt3bb.1, were identified in ricefield eels. Real-time quantitative PCR analysis showed that all four dnmt3 mRNAs were detected broadly in tissues examined, with testicular expression at relatively high levels. In the testis, immunostaining for all four Dnmt3 forms was mainly localized to spermatocytes, which also contained highly methylated DNA. All three forms of Gonadotropin-releasing hormone (Gnrh) in the ricefield eel were shown to decrease the expression of dnmt3 genes in the in vitro incubated testicular fragments through cAMP and IP3/Ca2+ pathways. Moreover, in vivo treatment of male fish with three forms of Gnrh decreased significantly the testicular Dnmt3 expression at both mRNA and protein levels, and the global DNA methylation levels. These results suggest that the expression of Dnmt3 and global DNA methylation in the testis of ricefield eels are potentially down-regulated by Gnrh, and reveal a novel regulatory mechanism of testicular Dnmt3 expression in vertebrates. PMID:28225069

  20. A gonadotropin-releasing hormone-like molecule modulates the activity of diverse central neurons in a gastropod mollusk, Aplysia californica

    Directory of Open Access Journals (Sweden)

    Biao eSun

    2011-09-01

    Full Text Available In vertebrates, gonadotropin-releasing hormone (GnRH is a crucial decapeptide that activates the hypothalamic-pituitary-gonadal (HPG axis to ensure successful reproduction. Recently, a GnRH-like molecule has been isolated from a gastropod mollusk, Aplysia californica. This GnRH (ap-GnRH is deduced to be an undecapeptide, and its function remains to be explored. Our previous study demonstrated that ap-GnRH did not stimulate a range of reproductive parameters. Instead, it affected acute behavioral and locomotive changes unrelated to reproduction. In this study, we used electrophysiology and retrograde tracing to further explore the central role of ap-GnRH. Sharp electrode intracellular recordings revealed that ap-GnRH had diverse effects on central neurons that ranged from excitatory, inhibitory, to the alteration of membrane potential. Unexpectedly, extracellular recordings revealed that ap-GnRH suppressed the onset of electrical afterdischarge (AD in bag cell neurons, suggesting an inhibitory effect on female reproduction. Lastly, using immunocytochemistry (ICC coupled with nickel-backfill, we demonstrated that some ap-GnRH neurons projected to efferent nerves known to innervate the foot and parapodia, suggesting ap-GnRH may directly modulate the motor output of these peripheral tissues. Overall, our results suggested that in A. californica, ap-GnRH more likely functioned as a central modulator of complex behavior and motor regulation rather than as a conventional reproductive stimulator.

  1. Effects of MboII and BspMI polymorphisms in the gonadotropin releasing hormone receptor (GnRHR) gene on sperm quality in Holstein bulls.

    Science.gov (United States)

    Yang, Wu-Cai; Tang, Ke-Qiong; Yu, Jun-Na; Zhang, Chun-Yan; Zhang, Xiao-Xia; Yang, Li-Guo

    2011-06-01

    The hypothalamic gonadotropin-releasing hormone receptor (GnRHR) plays an essential physiological role in reproductive function, which triggers the synthesis and release of luteinizing hormone and follicle stimulating hormone in the pituitary. The objective of this study was to investigate the effects of polymorphisms of GnRHR gene on the quality of fresh and frozen semen in Holstein bulls. The PCR-RFLP method was applied to detect G286A and T340C transitions determining MboII and BspMI polymorphisms, respectively, in the exon I of bovine GnRHR gene and evaluated its associations with sperm quality traits in 131 Holstein bulls. In polymorphic locus 286, bulls with the GA genotype had significantly higher sperm motility in frozen semen (FMOT) than GG genotype (P bulls with heterozygote CT genotype had significantly higher sperm motility (MOT), semen volume per ejaculate (VOL), and lower abnormal spermatozoa rate (ASR) than homozygote TT genotype (P Bulls contained one A allele or C allele had a favorable, positive effect on sperm quality traits. These results indicate that GnRHR gene can be a potential marker for improving sperm quality traits, and imply that bulls with GA or CT genotype should be selected in breeding program.

  2. Local duplication of gonadotropin-releasing hormone (GnRH receptor before two rounds of whole genome duplication and origin of the mammalian GnRH receptor.

    Directory of Open Access Journals (Sweden)

    Fatemeh Ameri Sefideh

    Full Text Available Gonadotropin-releasing hormone (GnRH and the GnRH receptor (GnRHR play an important role in vertebrate reproduction. Although many GnRHR genes have been identified in a large variety of vertebrate species, the evolutionary history of GnRHR in vertebrates is unclear. To trace the evolutionary origin of GnRHR we examined the conserved synteny of chromosomes harboring GnRHR genes and matched the genes to linkage groups of reconstructed vertebrate ancestor chromosomes. Consistent with the phylogenetic tree, three pairs of GnRHR subtypes were identified in three paralogous linkage groups, indicating that an ancestral pair emerged through local duplication before two rounds of whole genome duplication (2R. The 2R then led to the generation of six subtypes of GnRHR. Some subtypes were lost during vertebrate evolution after the divergence of teleosts and tetrapods. One subtype includes mammalian GnRHR and a coelacanth GnRHR that showed the greatest response to GnRH1 among the three types of GnRH. This study provides new insight into the evolutionary relationship of vertebrate GnRHRs.

  3. Associations of Gonadotropin-Releasing Hormone Receptor (GnRHR) and Neuropeptide Y (NPY) Genes' Polymorphisms with Egg-Laying Traits in Wenchang Chicken

    Institute of Scientific and Technical Information of China (English)

    WU Xu; ZHU Wen-qi; LI Hui-fang; YAN Mei-jiao; TANG Qing-ping; CHEN Kuan-wei; WANG Jin-yu; GAO Yu-shi; TU Yun-jie; YU Ya-bo

    2007-01-01

    Single nucleotide polymorphisms (SNP) of chicken gonadotropin-releasing hormone receptor (GnRHR) and neuropeptide Y (NPY) were selected to identify the genotypes of Wenchang (Chinese indigenous breed) chicken with restricton fragment length polymorphisms. The associations of the SNPs with the total egg production (NE), average days of continual laying (ADCL), and number of double-yolked eggs (DYE) traits were analyzed. The frequency of restriction enzyme A/a alleles in the population was for GnRHR 0.69 (Bpu1102 Ⅰ A) and 0.31 (Bpu1102 Ⅰ a) and for NPY 0.46 (Dra Ⅰ B) and 0.54 (Dra Ⅰ b). Trait data from a total of 120 hens, which were purebred introduced from Hainan Province, China from one generation were recorded. Two significant effects of genes' marker were found: for GnRHR and number of eggs (dominant; t= 2.67, df= 116) and NPY and number of eggs (additive; t= 1.97, df= 116). The current research supports the effects of GnRHR and NPY genes on egg-laying traits of chickens.

  4. Induction of castration by immunization of male dogs with recombinant gonadotropin-releasing hormone (GnRH)-canine distemper virus (CDV) T helper cell epitope p35.

    Science.gov (United States)

    Jung, Mi-Jeong; Moon, Young-Chan; Cho, Ik-Hyun; Yeh, Jung-Yong; Kim, Sun-Eui; Chang, Wha-Seok; Park, Seung-Young; Song, Chang-Seon; Kim, Hwi-Yool; Park, Keun-Kyu; McOrist, Steven; Choi, In-Soo; Lee, Joong-Bok

    2005-03-01

    Immunocastration is a considerable alternative to a surgical castration method especially in male animal species for alleviating unwanted male behaviors and characteristics. Induction of high titer of antibody specific for gonadotropin-releasing hormone (GnRH) correlates with the regression of testes. Fusion proteins composed of canine GnRH and T helper (Th) cell epitope p35 originated from canine distemper virus (CDV) F protein and goat rotavirus VP6 protein were produced in E. coli. When these fusion proteins were injected to male dogs which were previously immunized with CDV vaccine, the fusion protein of GnRH-CDV Th cell epitope p35 induced much higher antibody than that of GnRH-rotavirus VP6 protein or GnRH alone. The degeneration of spermatogenesis was also verified in the male dogs immunized with the fusion protein of GnRH-CDV Th cell epitope p35. These results indicate that canine GnRH conjugated to CDV Th cell epitope p35 acted as a strong immunogen and the antibody to GnRH specifically neutralized GnRH in the testes. This study also implies a potential application of GnRH-based vaccines for immunocastration of male pets.

  5. The effects of serotonin, dopamine, gonadotropin-releasing hormones, and corazonin, on the androgenic gland of the giant freshwater prawn, Macrobrachium rosenbergii.

    Science.gov (United States)

    Siangcham, Tanapan; Tinikul, Yotsawan; Poljaroen, Jaruwan; Sroyraya, Morakot; Changklungmoa, Narin; Phoungpetchara, Ittipon; Kankuan, Wilairat; Sumpownon, Chanudporn; Wanichanon, Chaitip; Hanna, Peter J; Sobhon, Prasert

    2013-11-01

    Neurotransmitters and neurohormones are agents that control gonad maturation in decapod crustaceans. Of these, serotonin (5-HT) and dopamine (DA) are neurotransmitters with known antagonist roles in female reproduction, whilst gonadotropin-releasing hormones (GnRHs) and corazonin (Crz) are neurohormones that exercise both positive and negative controls in some invertebrates. However, the effects of these agents on the androgenic gland (AG), which controls testicular maturation and male sex development in decapods, via insulin-like androgenic gland hormone (IAG), are unknown. Therefore, we set out to assay the effects of 5-HT, DA, l-GnRH-III, oct-GnRH and Crz, on the AG of small male Macrobrachium rosenbergii (Mr), using histological studies, a BrdU proliferative cell assay, immunofluorescence of Mr-IAG, and ELISA of Mr-IAG. The results showed stimulatory effects by 5-HT and l-GnRH-III through significant increases in AG size, proliferation of AG cells, and Mr-IAG production (Prosenbergii, as they induce increases in AG and testicular size, IAG production, and spermatogenesis. The mechanisms by which these occur are part of our on-going research.

  6. Assessment of stress levels in girls with central precocious puberty before and during long-acting gonadotropin-releasing hormone agonist treatment: a pilot study.

    Science.gov (United States)

    Menk, Tais A S; Inácio, Marlene; Macedo, Delanie B; Bessa, Danielle S; Latronico, Ana C; Mendonca, Berenice B; Brito, Vinicius Nahime

    2017-05-23

    The objective of the study was to determine the stress levels of girls with central precocious puberty (CPP) before and during treatment with a long-acting gonadotropin-releasing hormone agonist (GnRHa). The Child Stress Scale (CSS) was used for 10 unrelated girls with CPP before and after the first year of GnRHa treatment. The CSS is divided into four subscales (physical, psychological, psychological with depressive component and psychophysiological reactions). Through a quantitative analysis, it is possible to classify stress into four stages: alarm, resistance, near-exhaustion and exhaustion. At diagnosis, 90% of the girls showed stress levels scores at the alarm or resistance stage on at least one subscale, mostly in terms of physical and psychological reactions. The mean total stress score was significantly higher before when compared to after GnRHa treatment (43.4±15.6 vs. 28.9±9.7; pstress scores obtained in all subscales, except the one on psychophysiological reactions, were significantly higher before GnRHa treatment. Higher stress levels were a common finding in girls with CPP before treatment. The significant stress level reduction after pubertal suppression reinforces the idea that sexual precocity is a stressful condition in children. The CSS might be a useful tool for psychological assessment of patients with CPP.

  7. Defining the baseline in social life cycle assessment

    DEFF Research Database (Denmark)

    Jørgensen, Andreas; Finkbeiner, Matthias; Jørgensen, Michael Søgaard

    2010-01-01

    A relatively broad consensus has formed that the purpose of developing and using the social life cycle assessment (SLCA) is to improve the social conditions for the stakeholders affected by the assessed product's life cycle. To create this effect, the SLCA, among other things, needs to provide...... valid assessments of the consequence of the decision that it is to support. The consequence of a decision to implement a life cycle of a product can be seen as the difference between the decision being implemented and 'non-implemented' product life cycle. This difference can to some extent be found...... using the consequential environmental life cycle assessment (ELCA) methodology to identify the processes that change as a consequence of the decision. However, if social impacts are understood as certain changes in the lives of the stakeholders, then social impacts are not only related to product life...

  8. A life cycle database for parasitic acanthocephalans, cestodes, and nematodes

    Science.gov (United States)

    Benesh, Daniel P.; Lafferty, Kevin D.; Kuris, Armand

    2017-01-01

    Parasitologists have worked out many complex life cycles over the last ~150 years, yet there have been few efforts to synthesize this information to facilitate comparisons among taxa. Most existing host-parasite databases focus on particular host taxa, do not distinguish final from intermediate hosts, and lack parasite life-history information. We summarized the known life cycles of trophically transmitted parasitic acanthocephalans, cestodes, and nematodes. For 973 parasite species, we gathered information from the literature on the hosts infected at each stage of the parasite life cycle (8510 host-parasite species associations), what parasite stage is in each host, and whether parasites need to infect certain hosts to complete the life cycle. We also collected life-history data for these parasites at each life cycle stage, including 2313 development time measurements and 7660 body size measurements. The result is the most comprehensive data summary available for these parasite taxa. In addition to identifying gaps in our knowledge of parasite life cycles, these data can be used to test hypotheses about life cycle evolution, host specificity, parasite life-history strategies, and the roles of parasites in food webs.

  9. Triggering ovulation with gonadotropin-releasing hormone agonist versus human chorionic gonadotropin in polycystic ovarian syndrome. A randomized trial

    Directory of Open Access Journals (Sweden)

    Amr Hassaan Farag

    2015-12-01

    Full Text Available Objectives: To compare GnRH agonist to hCG for triggering ovulation in polycystic ovarian syndrome treated with clomiphene citrate. Study design: Prospective randomized study. Materials & methods: Eighty five infertile women with PCOS participated in a randomized allocation concealed prospective trial and had induction of ovulation with clomiphene citrate. GnRH agonist 0.2 mg subcutaneously (group 1 or hCG 10,000 IU intramuscularly (group 2 was given to trigger ovulation. Primary outcome was mid-luteal serum progesterone, while secondary outcomes were ovulation rates and clinical pregnancy rates along 3 cycles. Results: No difference was found between group 1 and group 2 regarding mean serum progesterone and clinical pregnancy rates in each cycle. Cumulative pregnancy rates were similar (17.14% versus 20% respectively; P = 0.332. Ovulation rates were 80% versus 68.6% (P = 0.413; 94.3% versus 90.9% (P = 0.669; 97.1% versus 93.7% (P = 0.603 in the two groups respectively. However, a significant rise in number of patients with mid-luteal serum progesterone >10 ng/mL was noted in the 3rd cycle between both groups, (P < 0.0001 for group 1 while P = 0.007 for group 2. Conclusion: Triggering ovulation with GnRH-a after treatment with clomiphene citrate in PCOS, in view of its known protective effect against OHSS, may be an effective physiological alternative to conventional hCG without compromising luteal function and pregnancy rates after repeated cycles of treatment.

  10. Break free from the product life cycle.

    Science.gov (United States)

    Moon, Youngme

    2005-05-01

    Most firms build their marketing strategies around the concept of the product life cycle--the idea that after introduction, products inevitably follow a course of growth, maturity, and decline. It doesn't have to be that way, says HBS marketing professor Youngme Moon. By positioning their products in unexpected ways, companies can change how customers mentally categorize them. In doing so, they can shift products lodged in the maturity phase back--and catapult new products forward--into the growth phase. The author describes three positioning strategies that marketers use to shift consumers' thinking. Reverse positioning strips away"sacred" product attributes while adding new ones (JetBlue, for example, withheld the expected first-class seating and in-flight meals on its planes while offering surprising perks like leather seats and extra legroom). Breakaway positioning associates the product with a radically different category (Swatch chose not to associate itself with fine jewelry and instead entered the fashion accessory category). And stealth positioning acclimates leery consumers to a new offering by cloaking the product's true nature (Sony positioned its less-than-perfect household robot as a quirky pet). Clayton Christensen described how new, simple technologies can upend a market. In an analogous way, these positioning strategies can exploit the vulnerability of established categories to new positioning. A company can use these techniques to go on the offensive and transform a category by demolishing its traditional boundaries. Companies that disrupt a category through positioning create a lucrative place to ply their wares--and can leave category incumbents scrambling.

  11. Life cycle assessment of biogas upgrading technologies.

    Science.gov (United States)

    Starr, Katherine; Gabarrell, Xavier; Villalba, Gara; Talens, Laura; Lombardi, Lidia

    2012-05-01

    This article evaluates the life cycle assessment (LCA) of three biogas upgrading technologies. An in-depth study and evaluation was conducted on high pressure water scrubbing (HPWS), as well as alkaline with regeneration (AwR) and bottom ash upgrading (BABIU), which additionally offer carbon storage. AwR and BABIU are two novel technologies that utilize waste from municipal solid waste incinerators - namely bottom ash (BA) and air pollution control residues (APC) - and are able to store CO(2) from biogas through accelerated carbonation processes. These are compared to high pressure water scrubbing (HPWS) which is a widely used technology in Europe. The AwR uses an alkaline solution to remove the CO(2) and then the solution - rich in carbonate and bicarbonate ions - is regenerated through carbonation of APC. The BABIU process directly exposes the gas to the BA to remove and immediately store the CO(2), again by carbonation. It was determined that the AwR process had an 84% higher impact in all LCA categories largely due to the energy intensive production of the alkaline reactants. The BABIU process had the lowest impact in most categories even when compared to five other CO(2) capture technologies on the market. AwR and BABIU have a particularly low impact in the global warming potential category as a result of the immediate storage of the CO(2). For AwR, it was determined that using NaOH instead of KOH improves its environmental performance by 34%. For the BABIU process the use of renewable energies would improve its impact since accounts for 55% of the impact. Copyright © 2011 Elsevier Ltd. All rights reserved.

  12. Life cycle assessment of regional brick manufacture

    Directory of Open Access Journals (Sweden)

    López-Aguilar, H. A.

    2016-06-01

    Full Text Available This document presents a Life Cycle Assessment (LCA study to quantify the environmental cradle-to-gate impact of the manufacture of brick for the construction industry, produced with material of igneous source. Its mineral composition and thermal isolation properties were characterized for use in real estate construction. The LCA results for brick manufacture using this material identified the greatest environmental impact to be associated with material extraction and its proportional cement content. Additionally, this document presents an evaluation of the environmental impact of the manufacturing process by comparing traditional fired clay brick and brick of the material under study. In conclusion, the studied material shows thermal insulation qualities and suitability for the manufacture of bricks with low incorporated energy.Este trabajo presenta un estudio de Análisis de Ciclo de Vida (ACV para cuantificar los impactos ambientales de la cuna a la puerta de la manufactura de ladrillos para la industria de la construcción, fabricados de un material de origen ígneo. Se caracterizó su composición mineralógica y propiedades de aislamiento térmico para ser usado en la construcción de inmuebles. Los resultados ACV de la fabricación de ladrillos de este material, identificaron la mayor contribución a los impactos ambientales asociados a la extracción del material y la cantidad proporcional de cemento. Adicionalmente, se presenta una evaluación comparativa del impacto ambiental entre la manufactura de un ladrillo tradicional de arcilla cocido y de un ladrillo del material en estudio. En conclusión el material estudiado muestra cualidades de aislamiento térmico y es adecuado para la fabricación de ladrillos con baja energía incorporada.

  13. Dealing with Emergy Algebra in the Life Cycle Assessment Framework

    Science.gov (United States)

    The Life Cycle Inventory (LCI) represents one of the four steps of the Life Cycle Assessment (LCA) methodology, which is a standardized procedure (ISO 14040:2006) to estimate the environmental impacts generated by the production, use and disposal of goods and services. In this co...

  14. EDITORIAL: THE INTERNATIONAL CONFERENCE ON LIFE CYCLE ASSESSMENT

    Science.gov (United States)

    This is a special issue of Journal of Life Cycle Assessment that includes selected papers from the Internatonal Conference and Exhibition on Life Cycle Assessment (InLCA). In April 2000, the EPA, with co-organizer IERE, held the InLCA conferencethat attracted over 265 attendees (...

  15. A Game to Teach the Life Cycles of Fungi

    Science.gov (United States)

    Blum, Abraham

    1976-01-01

    Presented is a biological game utilized to teach fungi life cycles to secondary biology students. The game is designed to overcome difficulties of correlating schematic drawings with images seen through the microscope, correlating life cycles of fungi and host, and understanding cyclic development of fungi. (SL)

  16. Methods for uncertainty propagation in life cycle assessment

    NARCIS (Netherlands)

    Groen, E.A.; Heijungs, R.; Bokkers, E.A.M.; Boer, de I.J.M.

    2014-01-01

    Life cycle assessment (LCA) calculates the environmental impact of a product over its entire life cycle. Uncertainty analysis is an important aspect in LCA, and is usually performed using Monte Carlo sampling. In this study, Monte Carlo sampling, Latin hypercube sampling, quasi Monte Carlo sampling,

  17. LIFE-CYCLE IMPACT ASSESSMENT DEMONSTRATION FOR THE BGU-24

    Science.gov (United States)

    The primary goal of this project was to develop and demonstrate a life-cycle impact assessment (LCIA) approach using existing life-cycle inventory (LCI) data on one of the propellants, energetics, and pyrotechnic (PEP) materials of interest to the U.S. Department of Defense (DoD)...

  18. LIFE-CYCLE IMPACT ASSESSMENT DEMONSTRATION FOR THE GBU-24

    Science.gov (United States)

    The primary goal of this project was to develop and demonstrate a life-cycle impact assessment (LCIA) approach using existing life-cycle inventory (LCI) data on one of the propellants, energetics, and pyro-technic (PEP) materials of interest to the U.S. Department of Defense (DoD...

  19. EVALUATING THE GREENNESS OF IONIC LIQUIDS VIA LIFE CYCLE ASSESSMENT

    Science.gov (United States)

    Ionic Liquids have been suggested as "greener" replacements to traditional solvents. However, the environmental impacts of the life cycle phases have not been studied. Such a "cradle to gate" Life Cycle Assessment (LCA) for comparing the environmental impact of various solvents...

  20. From BIM to life cycle information management in infrastructure

    NARCIS (Netherlands)

    Nederveen, G.A. van; Wolfert, R.; Ruitenbeek, M. van de

    2014-01-01

    In principle, Building Information Modelling (BIM) should provide a basis for infrastructure information management during the whole life-cycle. In practice however, the use of BIM is normally limited to the design and construction phases. It seems that the use of BIM information in other life-cycle

  1. Life Cycle Thinking, Measurement and Management for Food System Sustainability.

    Science.gov (United States)

    Pelletier, Nathan

    2015-07-07

    Food systems critically contribute to our collective sustainability outcomes. Improving food system sustainability requires life cycle thinking, measurement and management strategies. This article reviews the status quo and future prospects for bringing life cycle approaches to food system sustainability to the fore.

  2. THE INTERNATIONAL WORKSHOP ON ELECTRICITY DATA FOR LIFE CYCLE INVENTORIES

    Science.gov (United States)

    A three day workshop was held in October 2001 to discuss life cycle inventory data for electricity production. Electricity was selected as the topic for discussion since it features very prominently in the LCA results for most product life cycles, yet there is no consistency in h...

  3. Dealing with Emergy Algebra in the Life Cycle Assessment Framework

    Science.gov (United States)

    The Life Cycle Inventory (LCI) represents one of the four steps of the Life Cycle Assessment (LCA) methodology, which is a standardized procedure (ISO 14040:2006) to estimate the environmental impacts generated by the production, use and disposal of goods and services. In this co...

  4. LIFE CYCLE DESIGN OF AMORPHOUS SILICON PHOTOVOLTAIC MODULES

    Science.gov (United States)

    The life cycle design framework was applied to photovoltaic module design. The primary objective of this project was to develop and evaluate design metrics for assessing and guiding the Improvement of PV product systems. Two metrics were used to assess life cycle energy perform...

  5. Effective Integration of Life Cycle Engineering in Education

    NARCIS (Netherlands)

    Oude Luttikhuis, Ellen; Toxopeus, Marten E.; Lutters, Diederick

    2015-01-01

    In practice, applying life cycle engineering in product design and development requires an integrated approach, because of the many stakeholders and variables (e.g. cost, environmental impact, energy, safety, quality) involved in a complete product life cycle. In educating young engineers, the same

  6. From BIM to life cycle information management in infrastructure

    NARCIS (Netherlands)

    Nederveen, G.A. van; Wolfert, R.; Ruitenbeek, M. van de

    2014-01-01

    In principle, Building Information Modelling (BIM) should provide a basis for infrastructure information management during the whole life-cycle. In practice however, the use of BIM is normally limited to the design and construction phases. It seems that the use of BIM information in other life-cycle

  7. The LIFE project research review: mapping the landscape, riding a life cycle

    OpenAIRE

    Watson, J

    2005-01-01

    The LIFE project research review investigates both life cycle costing and digital preservation, with a view to creating a useable life cycle costing model that can be applied to digital preservation within an HE/FE environment. The general concept of life cycle costing (LCC) is explored as a cost management tool. LCC is concerned with all stages of a life cycle, from inception to retirement. “Life cycles” are used in many arenas; this broader context is also taken into account. Although...

  8. Life cycle assessment and life cycle costing of bioethanol from sugarcane in Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Luo, Lin; Van der Voet, Ester; Huppes, Gjalt [Institute of Environmental Sciences (CML), Leiden University, P.O. Box 9518, 2300 RA, Leiden (Netherlands)

    2009-08-15

    Brazil has always been the pioneer in the application of bioethanol as a main fuel for automobiles, hence environmental and economic analyses of the Brazilian ethanol industries are of crucial importance. This study presents a comparative life cycle assessment (LCA) on gasoline and ethanol as fuels, and with two types of blends of gasoline with bioethanol, all used in a midsize car. The focus is on a main application in Brazil, sugarcane based ethanol. The results of two cases are presented: base case - bioethanol production from sugarcane and electricity generation from bagasse; future case - bioethanol production from both sugarcane and bagasse and electricity generation from wastes. In both cases sugar is co-produced. The life cycles of fuels include gasoline production, agricultural production of sugarcane, ethanol production, sugar and electricity co-production, blending ethanol with gasoline to produce E10 (10% of ethanol) and E85 (85%), and finally the use of gasoline, E10, E85 and pure ethanol. Furthermore, a life cycle costing (LCC) was conducted to give an indication on fuel economy in both cases. The results show that in the base case less GHG is emitted; while the overall evaluation of these fuel options depends on the importance attached to different impacts. The future case is certainly more economically attractive, which has been the driving force for development in the ethanol industry in Brazil. Nevertheless, the outcomes depend very much on the assumed price for crude oil. In LCC a steady-state cost model was used and only the production cost was taken into account. In the real market the prices of fuels are very much dependent on the taxes and subsidies. Technological development can help in lowering both the environmental impact and the prices of the ethanol fuels. (author)

  9. Addressing the effect of social life cycle assessments

    DEFF Research Database (Denmark)

    Jørgensen, Andreas; Dreyer, Louise Camilla; Wangel, Arne

    2012-01-01

    Purpose: In the recently published ‘Guidelines for social life cycle assessment of products’, it is stated that the ultimate objective of developing the social life cycle assessment (SLCA) is to promote improvements of social conditions for the stakeholders in the life cycle. This article addresses...... how the SLCA should be developed so that its use promotes these improvements. Methods: Hypotheses of how the use of SLCA can promote improvement of social conditions in the life cycle are formulated, after which theories and empirical findings from relevant fields of research are used to address...... the validity of these hypotheses. Results: Three in some cases potentially overlapping SLCA approaches are presented, assumed to create a beneficial effect in the life cycle in different ways. However, empirical and theoretical findings show that the beneficial effects proposed to arise from the use of each...

  10. Firm Life Cycle, Book-Tax Differences and Earnings Persistence

    Directory of Open Access Journals (Sweden)

    Antonio Lopo Martinez

    2016-06-01

    Full Text Available The objective in this study is to show if the life cycle explains the relation between the Book-Tax Differences (BTDs and earnings persistence, as well as to inform on the future gains and their relation with the BTDs. Therefore, univariate tests were applied to verify the differences between the mean BTDS, life cycle stages and regression coefficient for the Earnings Before Income Tax (EBIT. The study focused on Brazilian publicly traded companies between 2009 and 2013. The results indicated that the control of earnings persistence was related with the stages of the life cycle. The information relevance of the life cycle and the Book-Tax Differences for earnings persistence is registered. In conclusion, the firm life cycle should be included in the analysis of the relation between the BTDs and earnings persistence. The evidence registered here is crucial to identify the quality of the earnings and incorporate them into earnings valuation models.

  11. Comparative life cycle assessment and life cycle costing of lodging in the Himalaya

    DEFF Research Database (Denmark)

    Bhochhibhoya, Silu; Pizzol, Massimo; Achten, Wouter M J;

    2016-01-01

    , maintenance and material replacement. The study includes a sensitivity analysis focusing on the lifespan of buildings, occupancy rate and discount and inflation rates. The functional unit was formulated as the ‘Lodging of one additional guest per night’, and the time horizon is 50 years of building lifespan....... Both primary and secondary data were used in the life cycle inventory. Results and discussion The modern building has the highest global warming potential (kg CO2-eq) as well as higher costs over 50 years of building lifespan. The results show that the use stage is responsible for the largest share...

  12. Premenstrual Exacerbation of Life-Threatening Asthma: Effect of Gonadotrophin Releasing Hormone Analogue Therapy

    Directory of Open Access Journals (Sweden)

    Alun L Edwards

    1996-01-01

    Full Text Available Variability in the severity of asthma during various phases of the menstrual cycle has been frequently suspected. However, the hormonal changes that might affect mediators of bronchospasm have yet to be elucidated. The case of a 41-year-old woman suffering from longstanding asthma with life-threatening exacerbations is reported. The patient was treated with buserelin, a gonadotropin releasing hormone (GnRH analogue, which created a temporary chemical menopause and thus permitted diagnosis of a premenstrual exacerbation of asthma and offered insight into potential therapy. GnRH analogues may therefore be of value in assessing women with severe asthma suspected to vary with the menstrual cycle. The addition of estrogens and progestins at the same time as treatment with GnRH analogue may be of value in determining the role of these hormones in the pathogenesis of menstrually related exacerbations of asthma.

  13. Estrogen receptor beta and 2-arachydonoylglycerol mediate the suppressive effects of estradiol on frequency of postsynaptic currents in gonadotropin-releasing hormone neurons of metestrous mice: an acute slice electrophysiological study

    Directory of Open Access Journals (Sweden)

    Flóra eBálint

    2016-03-01

    Full Text Available Gonadotropin-releasing hormone (GnRH neurons are controlled by 17β-estradiol (E2 contributing to the steroid feedback regulation of the reproductive axis. In rodents, E2 exerts a negative feedback effect upon GnRH neurons throughout the estrus-diestrus phase of the ovarian cycle. The present study was undertaken to reveal the role of estrogen receptor subtypes in the mediation of the E2 signal and elucidate the downstream molecular machinery of suppression. The effect of E2 administration at low physiological concentration (10 pM on GnRH neurons in acute brain slices obtained from metestrous GnRH-GFP mice was studied under paradigms of blocking or activating estrogen receptor subtypes and interfering with retrograde 2-arachydonoylglycerol (2-AG signaling. Whole-cell patch clamp recordings revealed that E2 significantly diminished the frequency of spontaneous postsynaptic currents (sPSCs in GnRH neurons (49. 62±7.6% which effect was abolished by application of the ERα/β blocker Faslodex (1 µM. Pretreatment of the brain slices with cannabinoid receptor type 1 (CB1 inverse agonist AM251 (1 µM and intracellularly applied endocannabinoid synthesis blocker THL (10 µM significantly attenuated the effect of E2 on the sPSCs. E2 remained effective in the presence of TTX indicating a direct action of E2 on GnRH cells. The ERβ specific agonist DPN (10 pM also significantly decreased the frequency of miniature postsynaptic currents (mPSCs in GnRH neurons. In addition, the suppressive effect of E2 was completely blocked by the selective ERβ antagonist PHTPP (1 µM indicating that ERβ is required for the observed rapid effect of the E2. In contrast, the ERα agonist PPT (10 pM or the membrane-associated G protein-coupled estrogen receptor (GPR30 agonist G1 (10 pM had no significant effect on the frequency of mPSCs in these neurons. AM251 and THL significantly abolished the effect of E2 whereas AM251 eliminated the action of DPN on the mPSCs. These

  14. Life Cycle Development of Obesity and Its Determinants

    OpenAIRE

    Cavaco, Sandra; Eriksson, Tor; Skalli, Ali

    2011-01-01

    This paper is concerned with how obesity and some of its determinants develop over individuals’ life cycles. In particular we examine empirically the role and relative importance of early life conditions (parents’ education and socioeconomic status) and individuals’ own education as adults and how their impacts on the probability of overweight and obesity evolves over the life cycle. As the data set includes information about the individuals’ health behaviours (smoking and physical exercise) ...

  15. A Life-Cycle Analysis of Social Security with Housing

    OpenAIRE

    Chen, Kaiji

    2009-01-01

    This paper incorporates two features of housing in a life-cycle analysis of social security: housing as a durable good and housing market frictions. We find that with housing as a durable good unfunded social security substantially crowds out housing consumption throughout the life cycle. By contrast, aggregate non-durable consumption is higher when social security is present, although it is postponed until late in life. Moreover, in the presence of housing market frictions, social security l...

  16. Life cycle analysis of transportation fuel pathways

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-02-24

    The purpose of this work is to improve the understanding of the concept of life cycle analysis (LCA) of transportation fuels and some of its pertinent issues among non-technical people, senior managers, and policy makers. This work should provide some guidance to nations considering LCA-based policies and to people who are affected by existing policies or those being developed. While the concept of employing LCA to evaluate fuel options is simple and straightforward, the act of putting the concept into practice is complex and fraught with issues. Policy makers need to understand the limitations inherent in carrying out LCA work for transportation fuel systems. For many systems, even those that have been employed for a 100 years, there is a lack of sound data on the performance of those systems. Comparisons between systems should ideally be made using the same tool, so that differences caused by system boundaries, allocation processes, and temporal issues can be minimized (although probably not eliminated). Comparing the results for fuel pathway 1 from tool A to those of fuel system 2 from tool B introduces significant uncertainty into the results. There is also the question of the scale of system changes. LCA will give more reliable estimates when it is used to examine small changes in transportation fuel pathways than when used to estimate large scale changes that replace current pathways with completely new pathways. Some LCA tools have been developed recently primarily for regulatory purposes. These tools may deviate from ISO principles in order to facilitate simplicity and ease of use. In a regulatory environment, simplicity and ease of use are worthy objectives and in most cases there is nothing inherently wrong with this approach, particularly for assessing relative performance. However, the results of these tools should not be confused with, or compared to, the results that are obtained from a more complex and rigorous ISO compliant LCA. It should be

  17. The life-cycle squeeze: The interaction of men's occupational and family life cycles.

    Science.gov (United States)

    Oppenheimer, V K

    1974-05-01

    This paper is concerned with analyzing one structural source of pressure for wives to contribute to family income. This is the "life-cycle squeeze"-the situation where a man's resources are inadequate to meet the needs engendered by the number and ages of his children. Studies of how economic needs vary by family life-cycle stage indicate that one high point of need occurs when men are in their forties and early fifties. However, 1960 Census data on earnings patterns by age indicate that in only relatively high-level professional, managerial and sales occupations do average earnings peak at the same time family income needs are peaking. For most blue-collar and many medium- and low-level white collar occupations, median earnings are highest for younger men, and men at an age when family costs are at their maximum are earning somewhat less, on the average. As a consequence, the families of such men run the risk of a deterioration in their level of living unless an additional income is brought into the household.

  18. Life Cycle Assessment and Life Cycle Cost Analysis of Magnesia Spinel Brick Production

    Directory of Open Access Journals (Sweden)

    Aysun Özkan

    2016-07-01

    Full Text Available Sustainable use of natural resources in the production of construction materials has become a necessity both in Europe and Turkey. Construction products in Europe should have European Conformity (CE and Environmental Product Declaration (EPD, an independently verified and registered document in line with the European standard EN 15804. An EPD certificate can be created by performing a Life Cycle Assessment (LCA study. In this particular work, an LCA study was carried out for a refractory brick production for environmental assessment. In addition to the LCA, the Life Cycle Cost (LCC analysis was also applied for economic assessment. Firstly, a cradle-to-gate LCA was performed for one ton of magnesia spinel refractory brick. The CML IA method included in the licensed SimaPro 8.0.1 software was chosen to calculate impact categories (namely, abiotic depletion, global warming potential, acidification potential, eutrophication potential, human toxicity, ecotoxicity, ozone depletion potential, and photochemical oxidation potential. The LCC analysis was performed by developing a cost model for internal and external cost categories within the software. The results were supported by a sensitivity analysis. According to the results, the production of raw materials and the firing process in the magnesia spinel brick production were found to have several negative effects on the environment and were costly.

  19. Luteal phase supplementation after gonadotropin-releasing hormone agonist trigger in fresh embryo transfer: the American versus European approaches.

    Science.gov (United States)

    Humaidan, Peter; Engmann, Lawrence; Benadiva, Claudio

    2015-04-01

    The challenges in attaining an adequate luteal phase after GnRH agonist (GnRHa) trigger to induce final oocyte maturation have resulted in different approaches focused on rescuing the luteal phase insufficiency so that a fresh transfer can be carried out without jeopardizing IVF outcomes. Over the years, two different concepts have emerged: intensive luteal support with aggressive exogenous administration of E2 and P; and low-dose hCG rescue in the form of a small dose of hCG either on the day of oocyte retrieva or on the day of GnRHa trigger (the so called "dual trigger"). Both approaches have been shown to be effective in achieving pregnancy rates similar to those obtained after conventional hCG trigger and resulting in a very low risk of ovarian hyperstimulation syndrome (OHSS). Although the idea of freezing all embryos after GnRHa trigger and transferring them in a subsequent frozen-thawed cycle has been gaining momentum, a fresh transfer leading to the live birth of a healthy child is currently considered to be the goal of IVF treatment. Copyright © 2015 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  20. Response to gonadotropin-releasing hormone challenge: Seasonal variation in steroid production in a viviparous lizard, Tiliqua nigrolutea.

    Science.gov (United States)

    Edwards, Ashley; Jones, Susan M

    2017-04-01

    The hypothalamic-pituitary-gonadal axis plays a central role in the regulation of gamete maturation, sex steroid production and the stimulation of reproductive behaviours in vertebrates. In seasonal breeders, the timely activation and deactivation of this control system is important to ensure successful reproduction: this process is not well understood in species which breed irregularly. Males of the viviparous blotched blue-tongued lizard, Tiliqua nigrolutea, breed annually, while females display a multiennial cycle. We investigated seasonal variation in hypothalamic-pituitary-gonadal axis responsiveness in both sexes of T. nigrolutea. We measured changes in plasma concentrations of testosterone and estrogen in response to a single intraperitoneal injection of a GnRH agonist, chicken-II LH-RH, at three reproductively distinct times of year. Plasma testosterone concentrations in males were significantly increased during gonadal quiescence, but not initial or final spermatogenesis. There was no estrogen response in males at any time of year. Conversely, in females, there was an increase in plasma testosterone, but not estrogen, concentration, in reproductively quiescent females several months in advance of a successful pregnancy. These results indicate clear variation in HPG axis activity with sex, season and reproductive condition in this seasonally breeding viviparous lizard. This study opens the way for further investigation into the mechanisms by which internal (body condition) and external seasonal cues (temperature and photoperiod) are coordinated to regulate reproduction in irregularly-breeding reptiles.

  1. Comparing the Use of Uterine Artery Embolization to Gonadotropin-Releasing Hormone Agonists in Shrinking Fibroid Size: A Pilot Study in Kazakhstan

    Directory of Open Access Journals (Sweden)

    Balkenzhe Imankulova

    2015-09-01

    Full Text Available Introduction: Uterine fibroids are the most common benign tumor in women in Kazakhstan. In the past two decades, endoscopic surgery has played an important role in the development of gynecologic surgery, particularly in the treatment of uterine fibroids. The goal of this paper is to evaluate whether uterine artery embolization (UAE or gonadotropin-releasing hormone agonists (GnRHa prior to myomectomy was more effective in decreasing fibroid size and improving surgical outcomes in a pilot study of women in Kazakhstan.Methods: This pilot investigation included 24 patients separated into 2 groups: medication group (pre-treatment with GnRHa – 13 patients and embolization group (pre-treatment with UAE – 11 patients. All patients had uterine fibroids, 3-10 cm in diameter, and were treated with myomectomy at the National Research Center for Maternal and Child Health, Astana, Kazakhstan. All patient data were obtained by a retrospective medical records review. Descriptive statistics were utilized to characterize participant demographics data. Independent t-tests were used to analyze continuous variables, and Chi-square and Fisher’s exact tests were used where appropriate for count data.Results: The group treated with GnRHa had an operating time of 40±10 minutes longer than the group treated with UAE, due to the peri-operative difficulties encountered by surgeons in detecting the layer between the myometrium and fibroid capsule. The group treated with UAE experienced better patient outcomes (less blood loss, less surgical time, and reduced use of anesthesia and was a technically easier surgery due to visible differences in uterine layers.Conclusions: Despite the fact that both treatments (GnRHa and UAE were effective for fibroid shrinking, embolization resulted in more optimal surgical time and improved patient outcomes. Results of this pilot study need to be confirmed in a randomized clinical trial, specifically focused on Kazakhstan and the

  2. Phosphorylation substrates for protein kinase C in intact pituitary cells: characterization of a receptor-mediated event using novel gonadotropin-releasing hormone analogues

    Energy Technology Data Exchange (ETDEWEB)

    Strulovici, B.; Tahilramani, R.; Nestor, J.J. Jr.

    1987-09-22

    The involvement of protein kinase C in the signal transduction of gonadotropin-releasing hormone (GnRH) action was investigated with a GnRH superagonist, partial agonists, and antagonists in intact rat pituitary cells. Exposure of /sup 32/P-labeled cells to GnRH or to the superagonist (D-Nal(2)/sup 6/)GnRH induced the enhanced phosphorylation of 42-, 34-, 11-, and 10-kDa proteins and the dephosphorylation of a 15-kDa protein as assessed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis/autoradiography. This effect was blocked in a dose-dependent manner by potent GnRG antagonists. Downregulation of protein kinase C by prolonged incubation of the pituitary cells with high concentrations of active phorbol esters abolished protein kinase C activity and also prevented the phosphorylation induced by GnRN, or (D-Nal(2)/sup 6/)GnRH. The same effect was obtained by preincubating the cells with the protein kinase C inhibitor H-7. In this study the authors identify for the first time physiological substrates for protein kinase C in intact pituitary cells. They demonstrate a close quantitative correlation between the extent of translocation of protein kinase C, levels of phosphorylation of specific substrates in the intact cells, and the biological activity of the GnRH analogues with varying affinity for the GnRH receptor. These data strengthen the contention that the physiological effects of GnRH are primarily mediated via the phosphatidylinositol/Ca/sup 2 +/ signal transfer system and represent a first step toward defining the physiological substrates of protein kinase C and their role in the cascade of events that starts upon binding of GnRH to its receptor.

  3. Extracellular signal-regulated kinase mediates gonadotropin subunit gene expression and LH release responses to endogenous gonadotropin-releasing hormones in goldfish.

    Science.gov (United States)

    Klausen, Christian; Booth, Morgan; Habibi, Hamid R; Chang, John P

    2008-08-01

    The possible involvement of extracellular signal-regulated kinase (ERK) in mediating the stimulatory actions of two endogenous goldfish gonadotropin-releasing hormones (salmon (s)GnRH and chicken (c)GnRH-II) on gonadotropin synthesis and secretion was examined. Western blot analysis revealed the presence of ERK and phosphorylated (p)ERK in goldfish brain, pituitary, liver, ovary, testis and muscle tissue extracts, as well as extracts of dispersed goldfish pituitary cells and HeLa cells. Interestingly, a third ERK-like immunoreactive band of higher molecular mass was detected in goldfish tissue and pituitary cell extracts in addition to the ERK1-p44- and ERK2-p42-like immunoreactive bands. Incubation of primary cultures of goldfish pituitary cells with either a PKC-activating 4beta-phorbol ester (TPA) or a synthetic diacylglycerol, but not a 4alpha-phorbol ester, elevated the ratio of pERK/total (t)ERK for all three ERK isoforms. The stimulatory effects of TPA were attenuated by the PKC inhibitor GF109203X and the MEK inhibitor PD98059. sGnRH and cGnRH-II also elevated the ratio of pERK/tERK for all three ERK isoforms, in a time-, dose- and PD98059-dependent manner. In addition, treatment with PD98059 reduced the sGnRH-, cGnRH-II- and TPA-induced increases in gonadotropin subunit mRNA levels in Northern blot studies and sGnRH- and cGnRH-II-elicited LH release in cell column perifusion studies with goldfish pituitary cells. These results indicate that GnRH and PKC can activate ERK through MEK in goldfish pituitary cells. More importantly, the present study suggests that GnRH-induced gonadotropin subunit gene expression and LH release involve MEK/ERK signaling in goldfish.

  4. Effects of shortened photoperiod on gonadotropin-releasing hormone, gonadotropin, and vitellogenin gene expression associated with ovarian maturation in rainbow trout.

    Science.gov (United States)

    Choi, Sungchang; Lee, Cheul Ho; Park, Woodong; Kim, Dae-Jung; Sohn, Young Chang

    2010-01-01

    Reproductive activities of salmonids are synchronized by changes in photoperiod, which control the endocrine system via the brain-pituitary-gonadal axis. Gonadotropin-releasing hormone (GnRH) in the brain regulates synthesis and release of the pituitary gonadotropins (GTHs; FSH and LH). FSH and LH in turn stimulate the production of sex steroids for oocyte growth and maturation-Inducing steroid hormones for oocyte maturation and ovulation, respectively, in female salmonids. To clarify effects of long-term photoperiod manipulations on the reproductive activity of salmonids from early recrudescence to ovulation, we Investigated the gene expression profiles of GnRH, GTHs, and vitellogenin (VTG), and plasma sex steroids in female rainbow trout (Oncorhynchus mykiss). In addition, the percentages of eyed embryos and hatched alevins were examined together with the number of ovulated eggs to evaluate the effects of photoperiod regimes on egg quality. During late summer, the mRNA levels of GnRHs, GTHalpha, and LHbeta, and the plasma level of a maturational steroid (17alpha,20beta-dihydroxy-4-pregnen-3-one; 17,20beta-P) were significantly elevated by a gradually shortened photoperiod under constant temperature, in accordance with accelerated sexual maturation. The percentages of eyed embryos and hatched alevins from fish ovulated in August were comparable to those of control fish observed in December. These results clearly indicate that syntheses of GnRHs, LH, VTG, and 17,20beta-P are effectively accelerated by a programmed long-short photoperiod regime in early recrudescent female rainbow trout, without a marked deterioration in egg quality.

  5. Effects of lamprey PQRFamide peptides on brain gonadotropin-releasing hormone concentrations and pituitary gonadotropin-β mRNA expression.

    Science.gov (United States)

    Daukss, Dana; Gazda, Kristen; Kosugi, Takayoshi; Osugi, Tomohiro; Tsutsui, Kazuyoshi; Sower, Stacia A

    2012-06-01

    Within the RFamide peptide family, PQRFamide peptides that include neuropeptide FF and AF possess a C-terminal Pro-Gln-Arg-Phe-NH(2) motif. We previously identified PQRFamide peptides, lamprey PQRFa, PQRFa-related peptide (RP)-1 and -RP-2 by immunoaffinity purification in the brain of lamprey, one of the most ancient vertebrate species [13]. Lamprey PQRFamide peptide precursor mRNA was expressed in regions predicted to be involved in neuroendocrine regulation in the hypothalamus. However, the putative function(s) of lamprey PQRFamide peptides (PQRFa, PQRFa-RP-1 and PQRFa-RP-2) were not examined nor was the distribution of PQRFamide peptides examined in other tissues besides the brain. The objective of this study was to determine tissue distribution of lamprey PQRFamide peptide precursor mRNA, and to examine the effects of PQRFamide peptides on brain gonadotropin-releasing hormone (GnRH)-I, -II, and -III protein concentrations, and pituitary gonadotropin (GTH)-β mRNA expression in adult lampreys. Lamprey PQRFamide peptide precursor mRNA was expressed in the eye and the brain. Lamprey PQRFa at 100 μg/kg increased brain concentrations of lamprey GnRH-II compared with controls. PQRFa, PQRFa-RP-1 and PQRFa-RP-2 did not significantly change brain protein concentrations of either lamprey GnRH-I, -III, or lamprey GTH-β mRNA expression in the pituitary. These data suggest that one of the PQRFamide peptides may act as a neuroregulator of at least the lamprey GnRH-II system in adult female lamprey.

  6. Noradrenaline modulates the presence of gonadotropin-releasing hormone in ovary. The importance of its interrelation on the ovarian steroidogenesis and apoptosis on dioestrus II in rat.

    Science.gov (United States)

    Bronzi, Cynthia D; Orozco, Adriana S Vega; Rodriguez, Diego; Rastrilla, Ana María; Sosa, Zulema Y; Casais, Marilina

    2015-11-01

    The aim of this work was to investigate if noradrenaline (NA), added in the coeliac ganglion -superior ovarian nerve- ovary system (CG-SON-O) and in ovary incubation, modifies the release of ovarian progesterone (P4), gonadotropin-releasing hormone (GnRH) and oestradiol (E2), and the expression of 3β-HSD and 20α-HSD and proapoptotic bax and antiapoptotic bcl-2 on dioestrus II in the rat. The CG-SON-O system and the ovary were removed and placed in one cuvette containing Krebs-Ringer solution (control groups), and NA was added to the ganglion compartment in the ex vivo system and in the ovary compartment in the ovary incubation (experimental groups). P4, GnRH and E2 were measured by RIA, and gene expression was measured by RT-PCR. In the ex-vivo system, the release of ovarian P4 and GnRH and the expression of 3β-HSD and bax decreased; E2 and bcl-2 increased, and the bax/bcl-2 ratio decreased. However, in the ovary incubation, P4, GnRH, the expression of 3β-HSD and bax increased; E2, the expression of 20α-HSD and bcl-2 decreased while the bax/bcl-2 ratio increased, thus favoring apoptosis. The peripheral nervous system protected the ovary from the apoptotic mechanisms while in the ovary incubation the effect was reverted. Our results indicate that NA regulates ovarian steroidogenesis and apoptosis by modulating GnRH release from the coeliac ganglion and ovary, being NA a possible generator of a GnRH-gonadotropins axis in the ovary. This work is expected to contribute with new evidence of the clinical importance of catecholamines and GnRH in therapy and prevention of ovarian pathologies.

  7. Gonadotropin-releasing hormone (GnRH) receptors of cattle aggregate on the surface of gonadotrophs and are increased by elevated GnRH concentrations.

    Science.gov (United States)

    Kadokawa, Hiroya; Pandey, Kiran; Nahar, Asrafun; Nakamura, Urara; Rudolf, Faidiban O

    2014-11-30

    The presence of gonadotropin-releasing hormone (GnRH) receptors (GnRHRs) on gonadotrophs in the anterior pituitary (AP) is an important factor for reproduction control. However, little is known regarding GnRHR gene expression in gonadotrophs of cattle owing to the lack of an appropriate anti-GnRHR antibody. Therefore, an anti-GnRHR antibody for immunohistochemistry, flow cytometry, and immunocytochemistry assays was developed to characterize GnRHR gene expression in gonadotrophs. The anti-GnRHR antibody could suppress GnRH-induced LH secretion from cultured AP cells of cattle. The GnRHR, luteinizing hormone (LH), and follicle stimulating hormone (FSH) in the AP tissue was analyzed by fluorescence immunohistochemistry. The GnRHRs were aggregated on a limited area of the cell surface of gonadotrophs, possibly localized to lipid rafts. The LH secretion was stimulated with increasing amounts of GnRH; however, excessive concentrations (> 1 nM) resulted in a decrease in LH secretion. A novel method to purify gonadotrophs was developed using the anti-GnRHR antibody and fluorescence-activated cell sorting. Flow cytometric analysis using the anti-GnRHR antibody for cultured bovine AP cells, however, failed to support the hypothesis that GnRH induces GnRHR internalization and decreases GnRHR on the surface of GnRHR-positive AP cells. In contrast, immunocytochemistry using primary antibodies for cultured bovine AP cells showed that 10 nM (P < 0.05) and 100 nM (P < 0.01) GnRH, but not 0.01-1 nM GnRH, increased GnRHR in the cytoplasm of LH-positive cells. In conclusion, these data suggested that GnRHRs were aggregated on the surface of gonadotrophs and GnRHR inside gonadotrophs increased with elevated concentrations of GnRH.

  8. Cytoplasmic kinases downstream of GPR30 suppress gonadotropin-releasing hormone (GnRH)-induced luteinizing hormone secretion from bovine anterior pituitary cells.

    Science.gov (United States)

    Rudolf, Faidiban O; Kadokawa, Hiroya

    2016-01-01

    GPR30 is known as a membrane receptor for picomolar concentrations of estradiol. The GPR30-specific agonist G1 causes a rapid, non-genomic suppression of gonadotropin-releasing hormone (GnRH)-induced luteinizing hormone (LH) secretion from bovine anterior pituitary (AP) cells. A few studies have recently clarified that protein kinase A (PKA) and phosphorylated extracellular signal-regulated kinase (pERK) might be involved in cytoplasmic signaling pathways of GPR30 in other cells. Therefore, we tested the hypothesis that PKA and ERK kinase (MEK) are important cytoplasmic mediators for GPR30-associated non-genomic suppression of GnRH-induced LH secretion from bovine AP cells. Bovine AP cells (n = 8) were cultured for 3 days under steroid-free conditions. The AP cells were previously treated for 30 min with one of the following: 5000 nM of PKA inhibitor (H89), 1000 nM of MEK inhibitor (U0126), or a combination of H89 and U0126. Next, the AP cells were treated with 0.01 nM estradiol for 5 min before GnRH stimulation. Estradiol treatment without inhibitor pretreatment significantly suppressed GnRH-induced LH secretion (P < 0.01). In contrast, estradiol treatment after pretreatment with H89, U0126 or their combination had no suppressive effect on GnRH-induced LH secretion. The inhibitors also inhibited the G1 suppression of GnRH-induced LH secretion. Therefore, these data supported the hypothesis that PKA and MEK (thus, also pERK) are the intracellular mediators downstream of GPR30 that induce the non-genomic suppression of GnRH-induced LH secretion from bovine AP cells by estradiol or G1.

  9. Gonadotropin-releasing hormone for preservation of ovarian function during chemotherapy in lymphoma patients of reproductive age: a summary based on 434 patients.

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    Yaoyao Zhang

    Full Text Available BACKGROUND: Gonadotropin-releasing hormone agonists (GnRHa might play a role in preserving ovarian function in lymphoma patients by inhibiting chemotherapy-induced ovarian follicular damage. However, studies of its clinical efficacy have reported conflicting results. METHOD: We conducted a meta-analysis to determine the effect of the preservation of ovarian function by administering GnRHa in young patients with lymphoma undergoing chemotherapy. Seven studies were identified that met inclusion criteria and comprised 434 patients assigned to GnRHa combined chemotherapy or chemotherapy alone. RESULTS: The incidence of women with premature ovarian failure (POF demonstrated a statistically significant difference in favor of the use of GnRHa (OR=0.32, 95% CI 0.13-0.77. In addition, the final level of FSH in the GnRH group was significantly lower than control group. (MD= -11.73, 95% CI,-22.25- -1.20, and the final level of AMH in the GnRH group was significantly higher than control group (MD=0.80; 95% CI, 0.61-0.98. However, there was no statistically significant difference between treatment and the control groups in the incidence of a spontaneous pregnancy (OR=1.11; 95% CI, 0.55-2.26. CONCLUSION: This meta-analysis suggests that GnRHa may be effective in protecting ovarian function during chemotherapy in lymphoma patients. More well-designed prospective studies are needed to carry out for further understanding of this topic.

  10. Polymorphisms in luteinizing hormone receptor and hypothalamic gonadotropin-releasing hormone genes and their effects on sperm quality traits in Chinese Holstein bulls.

    Science.gov (United States)

    Sun, Li-Ping; Du, Qing-Zhi; Song, Ya-Pan; Yu, Jun-Na; Wang, Shu-Juan; Sang, Lei; Song, Luo-Wen; Yue, Yao-Min; Lian, Yu-Ze; Zhang, Sheng-Li; Hua, Guo-Hua; Zhang, Shu-Jun; Yang, Li-Guo

    2012-06-01

    Genes of hypothalamic-pituitary-gonadal axis play a key role in male reproductive performance. This study evaluated the polymorphisms of luteinizing hormone receptor (LHR) and hypothalamic gonadotropin-releasing hormone (GnRH) genes and their effects on sperm quality traits including semen volume per ejaculate (VOL), sperm density (SD), fresh sperm motility (FSM), thawed sperm motility (TSM), acrosome integrity rate (AIR), and abnormal sperm rate (ASR) collected from 205 Chinese Hostein bulls. The study bulls consisted of 205 mature Chinese Holstein, 27 Simmental, 28 Charolais, and 14 German yellow cattle. One single nucleotide polymorphism (SNP) (A883G) in exon 2 of GnRH and two SNPs (A51703G and G51656T) in intron 9 of LHR were identified in 274 bulls. Analysis of variance in 205 Chinese Holstein bulls showed that age had significant effect on both SD and FSM (P bulls with AG genotype had higher FSM than bulls with AA and GG genotype in LHR at 51,703 locus (P bulls with GG genotype had higher SD than bulls with TT genotype in LHR at G51656T locus (P < 0.10). Phenotypic correlation among the traits revealed that significant negative correlations were observed between ASR and AIR (r = -0.736, P < 0.01), ASR and AIR (r = -0.500, P < 0.01). There were moderate positive correlations between VOL and SD (r = 0.422, P < 0.01), as well as FSM (r = 0.411, P < 0.01). In conclusion, LHR may be a potential marker for sperm quality of SD and FSM.

  11. Rapid Anti-Inflammatory Effects of Gonadotropin-Releasing Hormone Antagonism in Rheumatoid Arthritis Patients with High Gonadotropin Levels in the AGRA Trial.

    Directory of Open Access Journals (Sweden)

    Anita Kåss

    Full Text Available Gonadotropin-releasing hormone (GnRH and pituitary gonadotropins, which appear to be proinflammatory, undergo profound secretory changes during events associated with rheumatoid arthritis (RA onset, flares, or improvement e.g. menopausal transition, postpartum, or pregnancy. Potential anti-inflammatory effects of GnRH-antagonists may be most pronounced in patients with high GnRH and gonadotropin levels. Therefore, we investigated the efficacy and safety of a GnRH-antagonist, cetrorelix, in RA patients with high gonadotropin levels.We report intention-to-treat post hoc analyses among patients with high gonadotropin levels (N = 53, i.e. gonadotropin levels>median, from our proof-of-concept, double-blind AGRA-study (N = 99. Patients with active longstanding RA, randomized to subcutaneous cetrorelix (5mg days1-2; 3mg days 3-5 or placebo, were followed through day 15. Only predefined primary and secondary endpoints were analyzed.The primary endpoint, Disease Activity Score of 28-joint counts with C-reactive protein (DAS28-CRP, improved with cetrorelix compared with placebo by day 5 (-1.0 vs. -0.4, P = 0∙010. By day 5, more patients on cetrorelix achieved at least a 20% improvement in the American College of Rheumatology scale (44% vs. 19%, P = 0.049, DAS28-CRP≤3.2 (24% vs. 0%, P = 0.012, and European League against Rheumatism 'Good-responses' (19% vs. 0%, P = 0.026. Tumor necrosis factor-α, interleukin-1β, interleukin-10, and CRP decreased with cetrorelix (P = 0.045, P = 0.034, P = 0.020 and P = 0.042 respectively compared with placebo by day 15. Adverse event rates were similar between groups.GnRH-antagonism produced rapid anti-inflammatory effects in RA patients with high gonadotropin levels. GnRH should be investigated further in RA.ClinicalTrials.gov NCT00667758.

  12. Clinical characteristics and follow-up of 5 young Chinese males with gonadotropin-releasing hormone deficiency caused by mutations in the KAL1 gene

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    Juan Li

    2016-02-01

    Full Text Available Isolated gonadotropin-releasing hormone (GnRH deficiency (IGD pertains to a group of genetic disorders consisting of anosmic hypogonadotropic hypogonadism (Kallmann syndrome, KS and normosmic idiopathic hypogonadotropic hypogonadism (nIHH. KS is genetically heterogeneous. We hereby present 5 young male patients with GnRH deficiency caused by mutations in the KAL1 gene. Their ages ranged from 9 months to 16 years. They were referred to our department for an endocrine consultation for micropenis. Hormone assays showed low circulating gonadotropins and testosterone. Molecular studies revealed KAL1 mutations in all cases, three reported nonsense sequence variants in the KAL1 gene were detected in 4 patients, respectively (c.784C > T (p.Arg 262*, c.1267C > T (p.Arg423*, and c.1270C > T (p.Arg424*, and one patient harbored a novel hemizygous sequence variant [c.227G > A (p.Trp76*]. Only one patient presented short stature without growth hormone deficiency and anosmia. Another patient had bilateral eyelid ptosis, trichiasis, and refractive error. This is the first report on the co-occurrence of a KAL1 gene mutation and tent-like upper lip in four patients. All of our cases had normal olfactory bulbs and showed no renal agenesis, cleft lip/palate, and hearing impairment. These cases expand our knowledge of the phenotype associated with KAL1 sequence variations, although the precise mechanism by which KAL1 gene influences the development of this phenotype is still unknown.

  13. Hormonal induction of spawning in 4 species of frogs by coinjection with a gonadotropin-releasing hormone agonist and a dopamine antagonist

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    Wignall Jacqui

    2010-04-01

    Full Text Available Abstract Background It is well known that many anurans do not reproduce easily in captivity. Some methods are based on administration of mammalian hormones such as human chorionic gonadotropin, which are not effective in many frogs. There is a need for simple, cost-effective alternative techniques to induce spawning. Methods Our new method is based on the injection of a combination of a gonadotropin-releasing hormone (GnRH agonist and a dopamine antagonist. We have named this formulation AMPHIPLEX, which is derived from the combination of the words amphibian and amplexus. This name refers to the specific reproductive behavior of frogs when the male mounts and clasps the female to induce ovulation and to fertilize the eggs as they are laid. Results We describe the use of the method and demonstrate its applicability for captive breeding in 3 different anuran families. We tested several combinations of GnRH agonists with dopamine antagonists using Lithobates pipiens. The combination of des-Gly10, D-Ala6, Pro-LHRH (0.4 microrams/g body weight and metoclopramide (10 micrograms/g BWt. MET was most effective. It was used in-season, after short-term captivity and in frogs artificially hibernated under laboratory conditions. The AMPHIPLEX method was also effective in 3 Argentinian frogs, Ceratophrys ornata, Ceratophrys cranwelli and Odontophrynus americanus. Conclusion Our approach offers some advantages over other hormonally-based techniques. Both sexes are injected only once and at the same time, reducing handling stress. AMPHIPLEX is a new reproductive management tool for captive breeding in Anura.

  14. The effect of dietary monensin on th luteinizing hormone response of prepuberal heifers given a multiple gonadotropin-releasing hormone challenge.

    Science.gov (United States)

    Randel, R D; Rhodes, R C

    1980-10-01

    Ten prepuberal Simmental X Brahman-Hereford heifers (average weight 208 +/- 4 kg) were randomly assigned to receive either 2.7 kg/head/day of ground milo containing 0 mg monensin sodium (C) or 2.7 kg/head/day of ground milo containing 200 mg monensin sodium (M). Both groups of animals (n = 5) received Coastal bermudagrass hay ad libitum throughout the trial. On day 21 of the feeding period all heifers were fitted with jugular cannulas. Immediately after cannulation, the heifers were injected IM with 100 microgram of gonadotropin-releasing hormone (GnRH) and blood was collected every 10 min for 4 hours. Four hours after the first GnRH challenge, a second 100-microgram GnRH injection was administered, and blood samples were collected at 10-min intervals for an additional 5 hours. Serum was stored at -20 C until radioimmunoassayed for luteinizing hormone (LH). The amount of LH released after each GnRH injection was greater in the heifers fed M than in the controls (P less than .05). Peak LH after the first GnRH challenge was greater (P less than .05) in heifers fed M than in controls. The area under th first GnRH induced LH curve tended (P less than .20) to be greater for the M group than for the controls. Peak LH concentration was greater in heifers fed M than in control heifers, as the duration (P less than .05) and area under the second GnRH-induced LH curve. In prepuberal heifers, dietary monensin appears to increase hypophyseal capability of releasing LH after a first and second GnRH challenge.

  15. Evaluation of dual trigger with gonadotropin-releasing hormone agonist and human chorionic gonadotropin in improving oocyte maturity rates: A prospective randomized study

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    Nalini Mahajan

    2016-01-01

    Full Text Available BACKGROUND: Mature oocytes are prerequisite for achieving the process of in vitro fertilization. Human chorionic gonadotropin (hCG is the standard trigger used for stimulating ovulation but is associated with ovarian hyperstimulation syndrome (OHSS. Gonadotropin-releasing hormone agonist trigger achieves oocyte maturation and lowers the incidence of OHSS, but it has limitations of higher pregnancy loss rate and miscarriage rates. Coadministration of both hormones is found to improve the pregnancy rates and the number of mature oocytes retrieved. We aimed to assess if the dual trigger is better than the conventional hCG in triggering oocyte maturation. METHODOLOGY: The study included 76 female patients aged 24–43 years who were randomly divided into two groups with 38 patients in each arm. The study included patients with antimullerian hormone (AMH 4 ng/ml and AFC/ovary >12 to avoid OHSS risk with hCG trigger. RESULTS: The study showed statistically insignificant differences between dual group versus hCG group in terms of the number of oocytes retrieved (10.0 ± 5.6 vs. 8.7 ± 5.0; P = 0.2816, the number of mature oocytes recovered (8.4 ± 5.0 vs. 7.2 ± 4.0; P = 0.2588, fertilization rate (5.9 ± 4.2 vs. 5.6 ± 3.3; P = 0.7390, and the number of usable embryos on day 3 (4.0 ± 3.0 vs. 4.0 ± 2.4; P = 0.8991. CONCLUSION: The dual trigger is equivalent to hCG in triggering oocyte maturation.

  16. Melanin-concentrating hormone (MCH) and gonadotropin-releasing hormones (GnRH) in Atlantic cod, Gadus morhua: tissue distributions, early ontogeny and effects of fasting.

    Science.gov (United States)

    Tuziak, Sarah M; Volkoff, Hélène

    2013-12-01

    Melanin-concentrating hormone (MCH) is classically known for its role in regulating teleost fish skin color change for environmental adaptation. Recent evidence suggests that MCH also has appetite-stimulating properties. The gonadotropin-releasing hormone (GnRH) peptide family has dual roles in endocrine control of reproduction and energy status in fish. Atlantic cod (Gadus morhua) are a commercially important aquaculture species inhabiting the shores of Atlantic Canada. In this study, we examine MCH and GnRH transcript expression profiles during early development as well as in central and peripheral tissues and quantify juvenile Atlantic cod MCH and GnRH hypothalamic mRNA expressions following food deprivation. MCH and GnRH3 cDNAs are maternally deposited into cod eggs, while MCH has variable expression throughout early development. GnRH2 and GnRH3 mRNAs "turn-on" during mid-segmentation once the brain is fully developed. For both MCH and GnRH, highest expression appears during the exogenous feeding stages, perhaps supporting their functions as appetite regulators during early development. MCH and GnRH transcripts are found in brain regions related to appetite regulation (telencephalon/preoptic area, optic tectum/thalamus, hypothalamus), as well as the pituitary gland and the stomach, suggesting a peripheral function in food intake regulation. Atlantic cod MCH mRNA is upregulated during fasting, while GnRH2 and GnRH3 transcripts do not appear to be influenced by food deprivation. In conclusion, MCH might be involved in stimulating food intake in juvenile Atlantic cod, while GnRHs may play a more significant role in appetite regulation during early development.

  17. Fast scan cyclic voltammetry as a novel method for detection of real-time gonadotropin-releasing hormone release in mouse brain slices.

    Science.gov (United States)

    Glanowska, Katarzyna M; Venton, B Jill; Moenter, Suzanne M

    2012-10-17

    Pulsatile gonadotropin-releasing hormone (GnRH) release is critical for the central regulation of fertility. There is no method allowing real-time GnRH detection in brain slices. We developed fast-scan cyclic voltammetry (FSCV) using carbon-fiber microelectrodes (CFME) to detect GnRH release and validated it using a biologically relevant system. FSCV parameters (holding potential, switching potential, and scan rate) were determined for stable GnRH detection in vitro, then optimized for GnRH detection in mouse brain slices. Placement of CFMEs in the median eminence (ME) near GnRH terminals allowed detection of both KCl-evoked and spontaneous GnRH release. GnRH release was also detected from GnRH fibers passing near GnRH soma and near fiber-fiber appositions in the preoptic area. No GnRH signal was detected from CFMEs in the ME of hpg mice, which lack GnRH, or in regions not containing GnRH neurons in wild-type mice; application of exogenous GnRH produced a signal similar to that observed for spontaneous/evoked endogenous GnRH release. Using an established mouse model that produces diurnal variations in GnRH neuron activity, we demonstrated corresponding changes in spontaneous GnRH release in the median eminence. These results validate FSCV to detect GnRH in brain slices and provide new information on the sites and amounts of GnRH release, providing insight into its neuromodulatory functions.

  18. Novel mechanism for gonadotropin-releasing hormone neuronal migration involving Gas6/Ark signaling to p38 mitogen-activated protein kinase.

    Science.gov (United States)

    Allen, Melissa P; Linseman, Daniel A; Udo, Hiroshi; Xu, Mei; Schaack, Jerome B; Varnum, Brian; Kandel, Eric R; Heidenreich, Kim A; Wierman, Margaret E

    2002-01-01

    Gonadotropin-releasing hormone (GnRH) is the central regulator of the reproductive axis. Normal sexual maturation depends on the migration of GnRH neurons from the olfactory placode to the hypothalamus during development. Previously, we showed restricted expression of the membrane receptor adhesion-related kinase (Ark) in immortalized cell lines derived from migratory but not postmigratory GnRH neurons. In addition, Ark and GnRH transcripts were detected along the GnRH neuron migratory route in the E13 mouse cribriform plate. In the present study, we examined the role of Ark and its ligand, Gas6 (encoded by growth arrest-specific gene 6), in GnRH neuron migration. Gas6 stimulated lamellipodial extension, membrane ruffling, and chemotaxis of immortalized NLT GnRH neuronal cells via the Ark receptor. Gas6/Ark signaling promoted activation of the Rho family GTPase Rac, and adenoviral-mediated expression of dominant negative N17Rac abolished Gas6/Ark-induced actin cytoskeletal reorganization and migration of GnRH neuronal cells. In addition, p38 MAPK was activated downstream of Ark and Rac, and inhibition of p38 MAPK with either SB203580 or adenoviral dominant negative p38alpha also blocked Gas6/Ark-mediated migration. Finally, downstream of Rac and p38 mitogen-activated protein kinase (MAPK), Gas6/Ark signaling promoted activation of MAPK-activated protein kinase 2 and induced phosphorylation of HSP25, a known regulator of cortical actin remodeling. The data are the first to demonstrate a migratory signaling pathway downstream of Ark/Axl family receptors and suggest a previously unidentified role for p38 MAPK in neuronal migration. Furthermore, these studies support a potential role for Ark in the regulation of GnRH neuronal migration.

  19. Hormonal induction of spawning in 4 species of frogs by coinjection with a gonadotropin-releasing hormone agonist and a dopamine antagonist

    Science.gov (United States)

    2010-01-01

    Background It is well known that many anurans do not reproduce easily in captivity. Some methods are based on administration of mammalian hormones such as human chorionic gonadotropin, which are not effective in many frogs. There is a need for simple, cost-effective alternative techniques to induce spawning. Methods Our new method is based on the injection of a combination of a gonadotropin-releasing hormone (GnRH) agonist and a dopamine antagonist. We have named this formulation AMPHIPLEX, which is derived from the combination of the words amphibian and amplexus. This name refers to the specific reproductive behavior of frogs when the male mounts and clasps the female to induce ovulation and to fertilize the eggs as they are laid. Results We describe the use of the method and demonstrate its applicability for captive breeding in 3 different anuran families. We tested several combinations of GnRH agonists with dopamine antagonists using Lithobates pipiens. The combination of des-Gly10, D-Ala6, Pro-LHRH (0.4 microrams/g body weight) and metoclopramide (10 micrograms/g BWt. MET) was most effective. It was used in-season, after short-term captivity and in frogs artificially hibernated under laboratory conditions. The AMPHIPLEX method was also effective in 3 Argentinian frogs, Ceratophrys ornata, Ceratophrys cranwelli and Odontophrynus americanus. Conclusion Our approach offers some advantages over other hormonally-based techniques. Both sexes are injected only once and at the same time, reducing handling stress. AMPHIPLEX is a new reproductive management tool for captive breeding in Anura. PMID:20398399

  20. Conservation of Three-Dimensional Helix-Loop-Helix Structure through the Vertebrate Lineage Reopens the Cold Case of Gonadotropin-Releasing Hormone-Associated Peptide.

    Science.gov (United States)

    Pérez Sirkin, Daniela I; Lafont, Anne-Gaëlle; Kamech, Nédia; Somoza, Gustavo M; Vissio, Paula G; Dufour, Sylvie

    2017-01-01

    GnRH-associated peptide (GAP) is the C-terminal portion of the gonadotropin-releasing hormone (GnRH) preprohormone. Although it was reported in mammals that GAP may act as a prolactin-inhibiting factor and can be co-secreted with GnRH into the hypophyseal portal blood, GAP has been practically out of the research circuit for about 20 years. Comparative studies highlighted the low conservation of GAP primary amino acid sequences among vertebrates, contributing to consider that this peptide only participates in the folding or carrying process of GnRH. Considering that the three-dimensional (3D) structure of a protein may define its function, the aim of this study was to evaluate if GAP sequences and 3D structures are conserved in the vertebrate lineage. GAP sequences from various vertebrates were retrieved from databases. Analysis of primary amino acid sequence identity and similarity, molecular phylogeny, and prediction of 3D structures were performed. Amino acid sequence comparison and phylogeny analyses confirmed the large variation of GAP sequences throughout vertebrate radiation. In contrast, prediction of the 3D structure revealed a striking conservation of the 3D structure of GAP1 (GAP associated with the hypophysiotropic type 1 GnRH), despite low amino acid sequence conservation. This GAP1 peptide presented a typical helix-loop-helix (HLH) structure in all the vertebrate species analyzed. This HLH structure could also be predicted for GAP2 in some but not all vertebrate species and in none of the GAP3 analyzed. These results allowed us to infer that selective pressures have maintained GAP1 HLH structure throughout the vertebrate lineage. The conservation of the HLH motif, known to confer biological activity to various proteins, suggests that GAP1 peptides may exert some hypophysiotropic biological functions across vertebrate radiation.

  1. Developmental programming: impact of fetal exposure to endocrine-disrupting chemicals on gonadotropin-releasing hormone and estrogen receptor mRNA in sheep hypothalamus.

    Science.gov (United States)

    Mahoney, Megan M; Padmanabhan, Vasantha

    2010-09-01

    Bisphenol-A (BPA) and methoxychlor (MXC), two endocrine-disrupting chemicals (EDCs) with estrogenic and antiandrogenic effects, disrupt the reproductive system. BPA has profound effects on luteinizing hormone (LH) surge amplitude, and MXC has profound effects on on LH surge timing in sheep. The neural mechanisms involved in the differential disruption of the LH surge by these two EDCs remain to be elucidated. We tested the hypothesis that the differential effects of BPA and MXC on LH surge system involved changes in hypothalamic gonadotropin-releasing hormone (GnRH) and estrogen receptors (ESR), ESR1 and ESR2, mRNA expression. Pregnant sheep were given daily injections of cottonseed oil (controls), MXC, or BPA (5mg/kg/day) from day 30 to 90 of gestation (term 147d). Offspring from these animals were euthanized as adults, during the late follicular phase following synchronization of estrus with prostaglandin F(2alpha), just before the expected onset of preovulatory LH surge and changes in mRNA expression of hypothalamic GnRH, ESR1, and ESR2 quantified following in situ hybridization. GnRH mRNA expression was significantly lower in both groups of EDC-treated females compared to controls. ESR1 expression was increased in prenatal BPA- but not MXC-treated females in medial preoptic area relative to controls. In contrast, ESR2 expression was reduced in the medial preoptic area of both EDC-treated groups. Differences in expression of ESR1/ESR2 receptors may contribute to the differential effects of BPA and MXC on the LH surge system. These findings provide support that prenatal exposure to EDCs alters the neural developmental trajectory leading to long-term reproductive consequences in the adult female.

  2. Effects of inorganic and organic manganese supplementation on gonadotropin-releasing hormone-I and follicle-stimulating hormone expression and reproductive performance of broiler breeder hens.

    Science.gov (United States)

    Xie, Jingjing; Tian, Chuanhuan; Zhu, Yongwen; Zhang, Liyang; Lu, Lin; Luo, Xugang

    2014-04-01

    Manganese is an essential microelement. Manganese deficiency affects reproduction performance and reproductive hormones in layers. However, little is known about its effects and the possible mechanism in regulating reproduction in broiler breeder hens. In the current study, broiler breeder hens at peak production were fed with diets supplemented with 0, 120, or 240 mg of Mn/kg as MnSO4 or Mn proteinate for 13 wk. Manganese supplementation did not alter egg laying rate, egg weight, fertility, hatchability, or hatchling weight over a 13-wk trial period. However, 240 mg of Mn/kg supplementation significantly increased serum Mn (P Manganese supplements increased the eggshell breaking strength (P < 0.05) without affecting the eggshell thickness. There was no difference in serum cholesterol and estradiol. Expression of follicle-stimulating hormone) and gonadotropin-releasing hormone-I (GnRH-I) genes was significantly elevated by 240 mg of Mn/kg (P < 0.05). Furthermore, inorganic Mn supplementation doubled GnRH-I expression compared with supplementation with the organic form (P < 0.05), although serum Mn was comparable between these 2 supplements. No obvious difference was shown in gene expression of luteinizing hormone, prolactin, GnRH-I receptor, inducible NO synthase, and dopamine receptor D1 in the pituitary as well as tyrosine hydroxylase and inducible NO synthase in the hypothalamus. This suggests that dietary Mn supplementation could improve eggshell quality in the long term. The central mechanism of nontoxic high doses of Mn suggested the transcriptional activation of GnRH-I and follicle-stimulating hormone genes. The central effect of inorganic Mn activating GnRH-I genes compared with the reduced effect by organic Mn could possibly be due to a decreased capacity of the latter passing through the blood-brain barrier.

  3. Bone mineral density and body composition in girls with idiopathic central precocious puberty before and after treatment with a gonadotropin-releasing hormone agonist

    Directory of Open Access Journals (Sweden)

    Sandra B. Alessandri

    2012-01-01

    Full Text Available OBJECTIVES: Idiopathic central precocious puberty and its postponement with a (gonadotropin-releasing hormone GnRH agonist are complex conditions, the final effects of which on bone mass are difficult to define. We evaluated bone mass, body composition, and bone remodeling in two groups of girls with idiopathic central precocious puberty, namely one group that was assessed at diagnosis and a second group that was assessed three years after GnRH agonist treatment. METHODS: The precocious puberty diagnosis and precocious puberty treatment groups consisted of 12 girls matched for age and weight to corresponding control groups of 12 (CD and 14 (CT girls, respectively. Bone mineral density and body composition were assessed by dual X-ray absorptiometry. Lumbar spine bone mineral density was estimated after correction for bone age and the mathematical calculation of volumetric bone mineral density. CONEP: CAAE-0311.0.004.000-06. RESULTS: Lumbar spine bone mineral density was slightly increased in individuals diagnosed with precocious puberty compared with controls; however, after correction for bone age, this tendency disappeared (CD = -0.74 + 0.9 vs. precocious puberty diagnosis = -1.73 + 1.2. The bone mineral density values of girls in the precocious puberty treatment group did not differ from those observed in the CT group. CONCLUSION: There is an increase in bone mineral density in girls diagnosed with idiopathic central precocious puberty. Our data indicate that the increase in bone mineral density in girls with idiopathic central precocious puberty is insufficient to compensate for the marked advancement in bone age observed at diagnosis. GnRH agonist treatment seems to have no detrimental effect on bone mineral density.

  4. Voltage-gated potassium currents are targets of diurnal changes in estradiol feedback regulation and kisspeptin action on gonadotropin-releasing hormone neurons in mice.

    Science.gov (United States)

    Pielecka-Fortuna, Justyna; DeFazio, R Anthony; Moenter, Suzanne M

    2011-11-01

    Estradiol has both negative and positive feedback actions upon gonadotropin-releasing hormone (GnRH) release; the latter actions trigger the preovulatory GnRH surge. Although neurobiological mechanisms of the transitions between feedback modes are becoming better understood, the roles of voltage-gated potassium currents, major contributors to neuronal excitability, are unknown. Estradiol alters two components of potassium currents in these cells: a transient current, I(A), and a sustained current, I(K). Kisspeptin is a potential mediator between estradiol and GnRH neurons and can act directly on GnRH neurons. We examined how estradiol, time of day, and kisspeptin interact to regulate these conductances in a mouse model exhibiting daily switches between estradiol negative (morning) and positive feedback (evening). Whole-cell voltage clamp recordings were made from GnRH neurons in brain slices from ovariectomized (OVX) mice and from OVX mice treated with estradiol (OVX+E). There were no diurnal changes in either I(A) or I(K) in GnRH neurons from OVX mice. In contrast, in GnRH neurons from OVX+E mice, I(A) and I(K) were greater during the morning when GnRH neuron activity is low and smaller in the evening when GnRH neuron activity is high. Estradiol increased I(A) in the morning and decreased it in the evening, relative to that in cells from OVX mice. Exogenously applied kisspeptin reduced I(A) regardless of time of day or estradiol status. Estradiol, interacting with time of day, and kisspeptin both depolarized I(A) activation. These findings extend our understanding of both the neurobiological mechanisms of estradiol negative vs. positive regulation of GnRH neurons and of kisspeptin action on these cells.

  5. Identification of a novel pituitary-specific chicken gonadotropin-releasing hormone receptor and its splice variants.

    Science.gov (United States)

    Shimizu, Mamiko; Bédécarrats, Grégoy Y

    2006-11-01

    In all vertebrates, GnRH regulates gonadotropin secretion through binding to a specific receptor on the surface of pituitary gonadotropes. At least two forms of GnRH exist within a single species, and several corresponding GnRH receptors (GNRHRs) have been isolated with one form being pituitary specific. In chickens, only one type of widely expressed GNRHR has previously been identified. The objectives of this study were to isolate a chicken pituitary-specific GNRHR and to determine its expression pattern during a reproductive cycle. Using a combined strategy of PCR and rapid amplification of cDNA ends (RACE), a new GNRHR (chicken GNRHR2) and two splice variants were isolated in domestic fowl (Gallus gallus domesticus). Full-length GNRHR2 and one of its splice variant mRNAs were expressed exclusively in the pituitary, whereas mRNA of the other splice variant was expressed in most brain tissues examined. The deduced amino acid sequence of full-length chicken GNRHR2 reveals a seven transmembrane domain protein with 57%-65% homology to nonmammalian GNRHRs. Semiquantitative real-time PCR revealed that mRNA levels of full-length chicken GNRHR2 in the pituitary correlate with the reproductive status of birds, with maximum levels observed during the peak of lay and 4 wk postphotostimulation in females and males, respectively. Furthermore, GnRH stimulation of GH3 cells that were transiently transfected with cDNA that encodes chicken GNRHR2 resulted in a significant increase in inositol phosphate accumulation. In conclusion, we isolated a novel GNRHR and its splice variants in chickens, and spatial and temporal gene expression patterns suggest that this receptor plays an important role in the regulation of reproduction.

  6. Life cycle assessment and the agri-food chain

    DEFF Research Database (Denmark)

    Hermansen, John Erik; Nguyen, T Lan T

    2012-01-01

    Our food consumption is responsible for a major part of the environmental impact related to our total consumption. Life cycle assessment (LCA) is a product-oriented tool that can be used efficiently to identify improvement options within the food chain covering a product’s life cycle from cradle...... of resource use and emissions associated with a product’s life cycle can be aggregated into impact categories (e.g., nonrenewable energy use, land occupation, global warming, acidification, etc.) and further aggregated into overall damage impacts (e.g., impacts on biodiversity, human health, and resource...

  7. Life cycle management. Condition monitoring of wind power plants; Life-cycle-management. Zustandsueberwachung von Windenergieanlagen

    Energy Technology Data Exchange (ETDEWEB)

    Wolff, R. [cmc GmbH, Kiel (Germany)

    2013-06-01

    The author of the contribution under consideration reports on maintenance strategies and condition monitoring in the field of wind energy. Beside the components in the drive train of wind turbines under consideration, the condition monitoring of the hardware systems and their software is explained. A brief overview of the field of machinery diagnosis and an explanation of the transmission of the measured data follow. Additional sensors such as sensors for the rotor blade monitoring, oil particles counter or oil quality sensors are described. In the field of diagnostic certainty, special follow-up studies such as video endoscopy, analysis of oil or grease, filter testing and material testing are discussed. The information from these thematic fields is used in the life-cycle management database for operationally relevant evaluations and considerations of economy of condition monitoring systems.

  8. Family influences on the career life cycle

    OpenAIRE

    Beauregard, T. Alexandra

    2007-01-01

    This chapter examines the myriad ways in which one’s family and personal life can impact an individual’s career. A review of some of the key research literature reveals that career choice is influenced by an individual’s values, attitudes, and expectations concerning how work should be balanced with the rest of life. Individuals are also susceptible to influence from their families of origin with regard to occupational choice and prioritizing work over family, or vice versa. Career opportunit...

  9. The Adult Life Cycle: Exploration and Implications.

    Science.gov (United States)

    Baile, Susan

    Most of the frameworks that have been constructed to mark off the changes in the cycle of adulthood are characterized by a particular focus such as developmental ages, the role of age and timing, or ego development. The theory of Erik Erikson, based upon his clinical observations, represents these crucial turning points in human development: ages…

  10. High-Cycle-Life Lithium Cell

    Science.gov (United States)

    Yen, S. P. S.; Carter, B.; Shen, D.; Somoano, R.

    1985-01-01

    Lithium-anode electrochemical cell offers increased number of charge/ discharge cycles. Cell uses components selected for compatibility with electrolyte solvent: These materials are wettable and chemically stable. Low vapor pressure and high electrochemical stability of solvent improve cell packaging, handling, and safety. Cell operates at modest temperatures - less than 100 degrees C - and is well suited to automotive, communications, and other applications.

  11. Life Cycle Assessment of Municipal Waste Management System ...

    African Journals Online (AJOL)

    Life Cycle Assessment of Municipal Waste Management System (Case Study: ... solid waste management systems for determine the optimum municipal solid waste ... include water pollution, air pollution, consumed energy and waste residues.

  12. Life Cycle Engineering – from methodology to enterprise culture

    DEFF Research Database (Denmark)

    Hauschild, Michael Zwicky; Alting, Leo; Poll, Christian

    2003-01-01

    of methodologies and tools for life cycle assessment and development of more eco-efficient products, from complex to simplified, catering to the needs of especially small and medium-sized enterprizes. The tools and data are in place, but dissemination lacks behind. Propagation of life cycle thinking and life cycle......As part of a sustainable development, the environmental efficiency of industry must increase by a factor four to ten. This engenders attention to the environmental impact of products and technical systems over their entire life cycle. The last decade has seen the development of a number...... engineering to larger parts of industry is attempted by strengthening the market pull through integrated product policy measures, and at the same time pushing through information activities, training and dissemination of tools. Experience hitherto shows that these forces are insufficient and that stronger...

  13. PETRI NET MODELING OF COMPUTER VIRUS LIFE CYCLE

    African Journals Online (AJOL)

    Dr Obe

    dynamic system analysis is applied to model the virus life cycle. Simulation of the .... of successful applications of Petri nets include distributed database systems, communication protocols, .... Concepts and Design". McGraw-Hill Computer.

  14. A new data architecture for advancing life cycle assessment

    Science.gov (United States)

    IntroductionLife cycle assessment (LCA) has a technical architecture that limits data interoperability, transparency, and automated integration of external data. More advanced information technologies offer promise for increasing the ease with which information can be synthesized...

  15. Life cycle human health impacts of 875 pesticides

    DEFF Research Database (Denmark)

    Fantke, Peter; Jolliet, Oliver

    2016-01-01

    Purpose Residues in field crops grown and harvested for human consumption are the main contributor to overall human exposure toward agricultural pesticides for the general population. However, exposure from crop residues is currently not considered in life cycle assessment practice. We therefore...... present a consistent framework for characterizing human toxicological impacts associated with pesticides applied to agricultural crops in the frame of life cycle impact assessment based on state-of-the-art data and methods. Methods We combine a dynamic multicrop plant uptake model designed for evaluating......-crop combinations of 10 orders of magnitude. Conclusions Our framework is operational for use in current life cycle impact assessment models, is made available for USEtox, and closes an important gap in the assessment of human exposure to pesticides. For ready use in life cycle assessment studies, we present...

  16. LIFE CYCLE DESIGN OF MILK AND JUICE PACKAGING

    Science.gov (United States)

    A life cycle design demonstration project was initiated between the U.S. Environmental Protection Agency, National Risk Management Research Laboratory, Dow Chemical Company, and the University of Michigan to investigate milk and juice packagie design. The primary objective of ...

  17. Life cycle assessment of a wind farm and related externalities

    DEFF Research Database (Denmark)

    Schleisner, Liselotte

    2000-01-01

    This paper concentrates on the assessment of energy and emissions related to the production and manufacture of materials for an offshore wind farm as well as a wind farm on land based on a life cycle analysis (LCA) model. In Denmark a model has been developed for life cycle assessments of different...... materials. The model is able to assess the energy use related to the production, transportation and manufacture of 1 kg of material. The energy use is divided into fuels used in order to estimate the emissions through the life cycle. In the paper the model and the attached assumptions are described......, and the model is demonstrated for two wind farms. The externalities for the wind farms are reported, showing the importance of life cycle assessment for renewable energy technologies. (C) 2000 Elsevier Science Ltd. All rights reserved....

  18. Estimating pesticide emissions for life cycle assessment of agricultural products

    DEFF Research Database (Denmark)

    Hauschild, Michael Zwicky; Røpke, Inge

    2004-01-01

    As the first country in Europe Denmark almost 2 years ago established an official center for Life Cycle Assessments and life cycle approaches as an element of the national IPP (Integrated Product Policy). The Danish EPA lends financial support to this important initiative, the aim of which is to: 1....... promote the use of Life Cycle Assessment and other product-oriented environmental tools in companies, 2. support companies and other in using environmental assessment of products and services, 3. ensure that the effort in the LCA area is based on a solid and scientific basis, and 4. maintain the well...... evaluation finished in September 2004. Important learnings for all who are engaged in dissemination of life cycle thinking in industry will be presented....

  19. Assessing environmental impacts in a life cycle perspective

    DEFF Research Database (Denmark)

    Hauschild, Michael Zwicky

    2005-01-01

    What are the environmental impacts from an armchairor a cellular phone or a steak, if you take into account all the activities needed to produce, maintain, use or consume and eventually dispose of it? Life cycle impact assessment is the part of life cycle assessment (LCA) where the inventory...... of material flows in the life cycle of a product are translated into environmental impacts and consumption of resources, and questions like these are given an answer. The environmental impacts may range from very local (e.g. land use) to global (like climate change). As an environmental analysis tool, LCA...... on the product system sets the frame for life cycle impact assessment (LCIA), and the bearings it has on current LCIA methodology are described in this paper together with the newest developments within this discipline....

  20. Information system life-cycle and documentation standards, volume 1

    Science.gov (United States)

    Callender, E. David; Steinbacher, Jody

    1989-01-01

    The Software Management and Assurance Program (SMAP) Information System Life-Cycle and Documentation Standards Document describes the Version 4 standard information system life-cycle in terms of processes, products, and reviews. The description of the products includes detailed documentation standards. The standards in this document set can be applied to the life-cycle, i.e., to each phase in the system's development, and to the documentation of all NASA information systems. This provides consistency across the agency as well as visibility into the completeness of the information recorded. An information system is software-intensive, but consists of any combination of software, hardware, and operational procedures required to process, store, or transmit data. This document defines a standard life-cycle model and content for associated documentation.

  1. Life-cycle of the African nightcrawler, Eudrilus eugeniae (Oligochaeta)

    African Journals Online (AJOL)

    1988-03-31

    Mar 31, 1988 ... Table 1 Published data on the life-cycle of Eudrilus eugeniae. Neuhauser. Rodriguez et al. .... reached this stage irridescent testes were discernable ventrally through the body .... animal waste products. The decrease in worm ...

  2. Understanding Life Cycle Issues: A Resource for School Leaders.

    Science.gov (United States)

    Levine, Sarah L.

    1987-01-01

    Reviews life cycle theories of developmental psychology and examines their applications in addressing the needs of adults who work in schools. Structural changes are needed if schools are to be responsive to the developmental needs of adults. (BJV)

  3. A framework for social life cycle impact assessment

    DEFF Research Database (Denmark)

    Dreyer, Louise Camilla; Hauschild, Michael Zwicky; Schierbeck, Jens

    2006-01-01

    Goal, Scope and Background. To enhance the use of life cycle assessment (LCA) as a tool in business decision-making, a methodology for Social life cycle impact assessment (LCIA) is being developed. Social LCA aims at facilitating companies to conduct business in a socially responsible manner...... by providing information about the potential social impacts on people caused by the activities in the life cycle of their product. The development of the methodology has been guided by a business perspective accepting that companies, on the one hand, have responsibility for the people affected...... of the companies along the life cycle to the product. This need is not present in Environmental LCA, where we base the connection on the physical link which exists between process and product. (2) Boundaries of the product system are determined with respect to the influence that the product manufacturer exerts...

  4. Life-cycle of the European compost worm Dendrobaena veneta ...

    African Journals Online (AJOL)

    1990-06-05

    Jun 5, 1990 ... The life-cycle of Dendrobaena veneta was studied to assess the potential ... development, growth and reproduction were investigated by rearing worms at ..... systems.Agric. Wmles 2: 43--60. RAMISCH. H. & GRAFF. o. 1985.

  5. Life cycle of the oriental compost worm Perionyx excavatus ...

    African Journals Online (AJOL)

    1989-03-21

    Mar 21, 1989 ... production, the life cycle of the vermicomposting species, Perionyx excavatus, was studied. The development, growth and reproduction of P. excavatus were investigated. ..... reproductive system of the earthworm: Perionyx.

  6. LIFE CYCLE DESIGN OF MILK AND JUICE PACKAGING

    Science.gov (United States)

    A life cycle design demonstration project was initiated between the U.S. Environmental Protection Agency, National Risk Management Research Laboratory, Dow Chemical Company, and the University of Michigan to investigate milk and juice packagie design. The primary objective of ...

  7. A new data architecture for advancing life cycle assessment

    Science.gov (United States)

    IntroductionLife cycle assessment (LCA) has a technical architecture that limits data interoperability, transparency, and automated integration of external data. More advanced information technologies offer promise for increasing the ease with which information can be synthesized...

  8. CORE COMPETENCIES AND PHASES OF THE ORGANIZATIONAL LIFE CYCLE

    OpenAIRE

    Ahmed, Selma Zone Fekih; Koubaa, Manel Belguith

    2013-01-01

    Organizations evolve according to well-defined phases during which it must raise some competencies more than others. This study discusses the importance of core competencies according to the phases of the life cycle of the organization. In this research, we mobilize the core competencies approach to explore the competence required at each stage of the organizational life cycle. The quantitative study of 50 Tunisian companies operating in the food sector shows that the importance of core ...

  9. Life-cycle analysis of renewable energy systems

    DEFF Research Database (Denmark)

    Sørensen, Bent

    1994-01-01

    An imlementation of life-cycle analysis (LCA) for energy systems is presented and applied to two renewable energy systems (wind turbines and building-integrated photovoltaic modules) and compared with coal plants......An imlementation of life-cycle analysis (LCA) for energy systems is presented and applied to two renewable energy systems (wind turbines and building-integrated photovoltaic modules) and compared with coal plants...

  10. Application of product life cycle concept to private label management

    OpenAIRE

    Sandra Horvat

    2013-01-01

    Private labels have recorded significant growth rates worldwide, becoming a serious threat to manufacturer brands. Development of private labels in many different product categories increased the complexity of their management. Therefore, this paper examines the possibility of using the product life cycle concept in private label management. Given that private labels are a specific brand type, it is necessary to adjust certain elements of the product life cycle concept, as it was developed on...

  11. Reverse food logistics during the product life cycle

    OpenAIRE

    Vlachos, IP

    2014-01-01

    This study aimed to examine reverse logistics across the food product life cycle. Based on a literature review of reverse logistics factors in food industry a set of measures were derived. A survey was conducted to examine the impact of reverse food logistics to supply chain performance across the different product life-cycle stages. A detailed questionnaire was sent to 200 practitioners with experience in food supply chain operations. In total, 48 usable questionnaires were returned, resulti...

  12. High Cycle-life Shape Memory Polymer at High Temperature

    Science.gov (United States)

    Kong, Deyan; Xiao, Xinli

    2016-09-01

    High cycle-life is important for shape memory materials exposed to numerous cycles, and here we report shape memory polyimide that maintained both high shape fixity (Rf) and shape recovery (Rr) during the more than 1000 bending cycles tested. Its critical stress is 2.78 MPa at 250 °C, and the shape recovery process can produce stored energy of 0.218 J g-1 at the efficiency of 31.3%. Its high Rf is determined by the large difference in storage modulus at rubbery and glassy states, while the high Rr mainly originates from its permanent phase composed of strong π-π interactions and massive chain entanglements. Both difference in storage modulus and overall permanent phase were preserved during the bending deformation cycles, and thus high Rf and Rr were observed in every cycle and the high cycle-life will expand application areas of SMPs enormously.

  13. The Life-Cycle Policy model

    NARCIS (Netherlands)

    Anciaux, N.L.G.; Bouganim, Luc; van Heerde, H.J.W.; Pucheral, Philippe; Apers, Peter M.G.

    2008-01-01

    Our daily life activity leaves digital trails in an increasing number of databases (commercial web sites, internet service providers, search engines, location tracking systems, etc). Personal digital trails are commonly exposed to accidental disclosures resulting from negligence or piracy and to ill

  14. The Life-Cycle Policy model

    NARCIS (Netherlands)

    Anciaux, Nicolas; Bouganim, Luc; Heerde, van Harold; Pucheral, Philippe; Apers, Peter M.G.

    2008-01-01

    Our daily life activity leaves digital trails in an increasing number of databases (commercial web sites, internet service providers, search engines, location tracking systems, etc). Personal digital trails are commonly exposed to accidental disclosures resulting from negligence or piracy and to ill

  15. The Life-Cycle Policy model

    NARCIS (Netherlands)

    Anciaux, N.L.G.; Bouganim, Luc; van Heerde, H.J.W.; Pucheral, Philippe; Apers, Peter M.G.

    Our daily life activity leaves digital trails in an increasing number of databases (commercial web sites, internet service providers, search engines, location tracking systems, etc). Personal digital trails are commonly exposed to accidental disclosures resulting from negligence or piracy and to

  16. LIFE CYCLE MANAGEMENT OF MUNICIPAL SOLID WASTE

    Science.gov (United States)

    This is a large, complex project in which a number of different research activities are taking place concurrently to collect data, develop cost and LCI methodologies, construct a database and decision support tool, and conduct case studies with communities to support the life cyc...

  17. How can a life cycle inventory parametric model streamline life cycle assessment in the wooden pallet sector?

    DEFF Research Database (Denmark)

    Niero, Monia; Di Felice, Francesco; Ren, Jingzheng

    2014-01-01

    This study discusses the use of parameterization within the life cycle inventory (LCI) in the wooden pallet sector, in order to test the effectiveness of LCI parametric models to calculate the environmental impacts of similar products. Starting from a single case study, the objectives of this paper......-linear regression allowed to define a correlation between the life cycle impact assessment (LCIA) category indicators considered and the most influencing parameters.The definition of LCI parametric model in the wooden pallet sector can effectively be used for calculating the environmental impacts of products......; these correlations can be used to improve the design of new wooden pallets.The conceptual scheme for defining the model is based on ISO14040-44 standards. First of all, the product system was defined identifying the life cycle of a generic wood pallet, as well as its life cycle stages. A list of independent...

  18. How can a life cycle inventory parametric model streamline life cycle assessment in the wooden pallet sector?

    DEFF Research Database (Denmark)

    Niero, Monia; Felice, Francesco, Di; Ren, Jingzheng

    2014-01-01

    Purpose This study discusses the use of parameterization within the life cycle inventory (LCI) in the wooden pallet sector, in order to test the effectiveness of LCI parametric models to calculate the environmental impacts of similar products. Starting from a single case study, the objectives......-based regression and one multiple non-linear regression allowed to define a correlation between the life cycle impact assessment (LCIA) category indicators considered and the most influencing parameters. Conclusions The definition of LCI parametric model in the wooden pallet sector can effectively be used......; these correlations can be used to improve the design of new wooden pallets. Methods The conceptual scheme for defining the model is based on ISO14040-44 standards. First of all, the product system was defined identifying the life cycle of a generic wood pallet, as well as its life cycle stages. A list of independent...

  19. Analysis within the systems development life-cycle

    CERN Document Server

    Rock-Evans, Rosemary

    1987-01-01

    Analysis within the Systems Development Life-Cycle: Book 1, Data Analysis-The Deliverables provides a comprehensive treatment of data analysis within the systems development life-cycle and all the deliverables that need to be collected in analysis. The purpose of deliverables is explained and a number of alternative ways of collecting them are discussed. This book is comprised of five chapters and begins with an overview of what """"analysis"""" actually means, with particular reference to tasks such as hardware planning and software evaluation and where they fit into the overall cycle. The ne

  20. LIFE CYCLE DESIGN OF A FUEL TANK SYSTEM

    Science.gov (United States)

    This life cycle design (LCD) project was a collaborative effort between the National Pollution Prevention Center at the University of Michigan, General Motors (GM), and the U.S. Environmental Protection Agency (EPA). The primary objective of this project was to apply life cyc...

  1. Models of life: epigenetics, diversity and cycles

    Science.gov (United States)

    Sneppen, Kim

    2017-04-01

    This review emphasizes aspects of biology that can be understood through repeated applications of simple causal rules. The selected topics include perspectives on gene regulation, phage lambda development, epigenetics, microbial ecology, as well as model approaches to diversity and to punctuated equilibrium in evolution. Two outstanding features are repeatedly described. One is the minimal number of rules to sustain specific states of complex systems for a long time. The other is the collapse of such states and the subsequent dynamical cycle of situations that restitute the system to a potentially new metastable state.

  2. Effect of feed restriction and initial body weight on growth performance, body composition, and hormones in male pigs immunized against gonadotropin-releasing factor.

    Science.gov (United States)

    Moore, K L; Mullan, B P; Kim, J C; Payne, H G; Dunshea, F R

    2016-09-01

    Pigs immunized against gonadotropin-releasing factor (GnRF) have increased carcass fatness compared to entire males; however, the timing of this increase in fatness after the second immunization against GnRF has not been determined. An experiment was conducted to identify and compare the growth performance, body composition, and physiological changes in immunocastrated males (IC males) at different BW and feeding levels. A total of 64 pigs were used in a 2 × 2 × 2 factorial experiment with the treatments being 1) sex (entire males or IC males), 2) initial BW (45.9 kg [light] or 78.3 kg [heavy]), and 3) feeding regime (2.5 times maintenance [restricted] or ad libitum). The pigs were individually housed, and the diets were fed for 4 wk after the second immunization against GnRF until slaughter at either 68.4 kg BW (light) or 105.8 kg BW (heavy). Immunocastrated males on a restricted feed intake had a lower ADG compared to entire males from d 15 to 28 and d 0 to 28 ( 0.011 and 0.011, respectively). Fat deposition was not affected by sex from d 0 to 14, but from d 15 to 28 IC males deposited 45 g/d more fat than entire males ( = 0.025). Immunocastrated male pigs fed ad libitum deposited 87 g/d more fat from d 15 to 28 than entire males fed ad libitum ( = 0.036). However, there was no difference in fat deposition between IC males and entire males when feed intake was restricted from d 15 to 28. Plasma urea nitrogen levels were greater in IC males compared to entire males from d 7 after the second immunization against GnRF ( 0.05 for d 7, 10, 14, 21, and 28). Plasma concentrations of IGF-1 were lower for IC males compared to entire males on d 3, 7, 10, and 28 ( 0.05 for all days). The following conclusions were made: 1) when pigs are immunized at a light BW (50 kg) and/or are on a restricted feed intake, they have a reduced propensity to deposit fat; however, the restriction in feed intake adversely affects growth rate. 2) The majority of fat deposition for males

  3. Differential regulation of two forms of gonadotropin-releasing hormone messenger ribonucleic acid by gonadotropins in human immortalized ovarian surface epithelium and ovarian cancer cells.

    Science.gov (United States)

    Choi, Jung-Hye; Choi, Kyung-Chul; Auersperg, Nelly; Leung, Peter C K

    2006-06-01

    Although gonadotropin-releasing hormone (GnRH) has been shown to play a role as an autocrine/ paracrine regulator of cell growth in ovarian surface epithelium and ovarian cancer, the factors which regulate the expression of GnRH and its receptor in these cells are not well characterized. In the present study, we employed real-time PCR to determine the potential regulatory effect of gonadotropins on the expression levels of GnRH I (the mammalian GnRH), GnRH II (a second form of GnRH) and their common receptor (GnRHR) in immortalized ovarian surface epithelial (IOSE-80 and IOSE-80PC) cells and ovarian cancer cell lines (A2780, BG-1, CaOV-3, OVCAR-3 and SKOV-3). The cells were treated with increasing concentrations (100 and 1000 ng/ml) of recombinant follicle-stimulating hormone (FSH) or luteinizing hormone (LH) for 24 h. Treatment with FSH or LH reduced GnRH II mRNA levels in both IOSE cell lines and in three out of five ovarian cancer cell lines (A2780, BG-1 and OVCAR-3). A significant decrease in GnRHR mRNA levels was observed in IOSE and ovarian cancer cells, except CaOV-3 cells, following treatment with FSH or LH. In contrast, treatment with either FSH or LH had no effect on GnRH I mRNA levels in these cells, suggesting that gonadotropins regulate the two forms of GnRH and its receptor differentially. In separate experiments, the effect of gonadotropins on the anti-proliferative action of GnRH I and GnRH II agonists in IOSE-80, OVCAR-3 and SKOV-3 cells was investigated. The cells were pretreated with FSH or LH (100 ng/ml) for 24 h after which they were treated with either GnRH I or GnRH II (100 ng/ml) for 2 days, and cell growth was assessed by the MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide] assay. Pretreatment of the cells with FSH or LH significantly reversed the growth inhibitory effect of GnRH I and GnRH II agonists in these cell types. These results provide the first demonstration of a potential interaction between gonadotropins and the

  4. Gonadotropin-releasing hormone, estradiol, and inhibin regulation of follicle-stimulating hormone and luteinizing hormone surges: implications for follicle emergence and selection in heifers.

    Science.gov (United States)

    Haughian, James M; Ginther, O J; Diaz, Francisco J; Wiltbank, Milo C

    2013-06-01

    Mechanisms regulating gonadotropin surges and gonadotropin requirements for follicle emergence and selection were studied in heifers. Experiment 1 evaluated whether follicular inhibins regulate the preovulatory luteinizing hormone (LH)/follicle-stimulating hormone (FSH) surges elicited by gonadotropin-releasing hormone (GnRH) injection (Hour = 0) and the subsequent periovulatory FSH surge. Treatments included control (n = 6), steroid-depleted bovine follicular fluid (bFF) at Hour -4 (n = 6), and bFF at Hour 6 (n = 6). Gonadotropins in blood were assessed hourly from Hours -6 to 36, and follicle growth tracked by ultrasound. Consistent with inhibin independence, bFF at Hour -4 did not impact the GnRH-induced preovulatory FSH surge, whereas treatment at Hour 6 delayed onset of the periovulatory FSH surge and impeded growth of a new follicular wave. Experiment 2 examined GnRH and estradiol (E2) regulation of the periovulatory FSH surge. Treatment groups were control (n = 8), GnRH-receptor antagonist (GnRHr-ant, n = 8), and E2 + GnRHr-ant (n = 4). GnRHr-ant (acyline) did not reduce the concentrations of FSH during the periovulatory surge and early follicle development (8.0 mm) was prevented by GnRHr-ant. Addition of E2 delayed both the onset of the periovulatory FSH surge and emergence of a follicular wave. Failure to select a dominant follicle in the GnRHr-ant group was associated with reduced concentrations of LH but not FSH. Maximum diameter of F1 in controls (13.3 ± 0.5 mm) was greater than in both GnRHr-ant (7.7 ± 0.3 mm) and E2 + GnRHr-ant (6.7 ± 0.8 mm) groups. Results indicated that the periovulatory FSH surge stems from removal of negative stimuli (follicular E2 and inhibin), but is independent of GnRH stimulation. Emergence and early growth of follicles (until about 8 mm) requires the periovulatory FSH surge but not LH pulses. However, follicular deviation and late-stage growth of a single dominant follicle requires GnRH-dependent LH pulses.

  5. Utility of gonadotropin-releasing hormone agonists for prevention of chemotherapy-induced ovarian damage in premenopausal women with breast cancer: a systematic review and meta-analysis

    Directory of Open Access Journals (Sweden)

    Shen YW

    2015-11-01

    Full Text Available Yan-Wei Shen,1 Xiao-Man Zhang,1 Meng Lv,1 Ling Chen,1 Tian-Jie Qin,1 Fan Wang,1 Jiao Yang,1 Pei-Jun Liu,2 Jin Yang1 1Department of Medical Oncology, 2Center for Translational Medicine, The First Affiliated Hospital of Xi’an Jiaotong University, Xi’an, People’s Republic of China Background: Premature ovarian failure and infertility following chemotherapy are major concerns for premenopausal women with breast cancer. A potential ovarian function preservation strategy is administration of gonadotropin-releasing hormone (GnRH agonists during adjuvant chemotherapy; however, studies of the clinical efficacy of GnRH agonists to protect chemotherapy-induced ovarian damage have shown mixed results. Objective: This meta-analysis study was designed to estimate the efficacy of GnRH agonists administered concurrently with chemotherapy to prevent chemotherapy-induced ovarian damage in premenopausal women with breast cancer. Methods: Electronic literature databases (PubMed, EMBASE, MEDLINE, Cochrane Library databases searching, China National Knowledge Infrastructure, Web of Science, and the Wanfang Data were searched for relevant randomized controlled trials (RCTs published until September 2015. Only RCTs that examined the effect of GnRH agonists for chemotherapy-induced ovarian failure in premenopausal women with breast cancer were selected. The rate of spontaneous resumption of menses and spontaneous pregnancy were collected. All data were analyzed by RevMan 5.3 (Cochrane Collaboration, Copenhagen, Denmark and Stata 12.0 (StataCorp, College Station, TX, USA. Results: Eleven RCTs with a total of 1,062 participants (GnRH agonists administered concurrently with chemotherapy, n=541; chemotherapy alone, n=521 were included in the meta-analysis. A significantly greater number of women treated with GnRH agonist experienced spontaneous resumption of menses after the adjuvant chemotherapy, yielding a pooled odds ratio of 2.57 (versus chemotherapy alone, 95

  6. Kisspeptins modulate the biology of multiple populations of gonadotropin-releasing hormone neurons during embryogenesis and adulthood in zebrafish (Danio rerio.

    Directory of Open Access Journals (Sweden)

    Yali Zhao

    Full Text Available Kisspeptin1 (product of the Kiss1 gene is the key neuropeptide that gates puberty and maintains fertility by regulating the gonadotropin-releasing hormone (GnRH neuronal system in mammals. Inactivating mutations in Kiss1 and the kisspeptin receptor (GPR54/Kiss1r are associated with pubertal failure and infertility. Kiss2, a paralogous gene for kiss1, has been recently identified in several vertebrates including zebrafish. Using our transgenic zebrafish model system in which the GnRH3 promoter drives expression of emerald green fluorescent protein, we investigated the effects of kisspeptins on development of the GnRH neuronal system during embryogenesis and on electrical activity during adulthood. Quantitative PCR showed detectable levels of kiss1 and kiss2 mRNA by 1 day post fertilization, increasing throughout embryonic and larval development. Early treatment with Kiss1 or Kiss2 showed that both kisspeptins stimulated proliferation of trigeminal GnRH3 neurons located in the peripheral nervous system. However, only Kiss1, but not Kiss2, stimulated proliferation of terminal nerve and hypothalamic populations of GnRH3 neurons in the central nervous system. Immunohistochemical analysis of synaptic vesicle protein 2 suggested that Kiss1, but not Kiss2, increased synaptic contacts on the cell body and along the terminal nerve-GnRH3 neuronal processes during embryogenesis. In intact brain of adult zebrafish, whole-cell patch clamp recordings of GnRH3 neurons from the preoptic area and hypothalamus revealed opposite effects of Kiss1 and Kiss2 on spontaneous action potential firing frequency and membrane potential. Kiss1 increased spike frequency and depolarized membrane potential, whereas Kiss2 suppressed spike frequency and hyperpolarized membrane potential. We conclude that in zebrafish, Kiss1 is the primary stimulator of GnRH3 neuronal development in the embryo and an activator of stimulating hypophysiotropic neuron activities in the adult, while

  7. Expression of salmon gonadotropin-releasing hormone (GnRH) and chicken GnRH-II precursor messenger ribonucleic acids in the brain and ovary of goldfish.

    Science.gov (United States)

    Lin, X W; Peter, R E

    1996-03-01

    The complementary DNAs (cDNA) encoding the [Trp7Leu8]gonadotropin-releasing hormone (salmon GnRH; sGnRH) precursor and the [His5Trp7Tyr8]GnRH (chicken GnRH-II; cGnRH-II) precursor of the goldfish brain were isolated and sequenced using reverse transcription and rapid amplification of cDNA ends (RACE). The sGnRH precursor cDNA consists of 540 bp, including an open reading frame of 282 bp, and the cGnRH-II precursor cDNA consists of 682 bp, including an open reading frame of 258 bp. The 94 amino acid-long goldfish sGnRH precursor and 86 amino acid-long goldfish cGnRH-II precursor have the same molecular architecture as GnRH precursors identified to date in other vertebrate species. Using two sets of primers designed to be sense and antisense to the goldfish brain sGnRH precursor cDNA sequence, reverse transcription-polymerase chain reaction (RT-PCR) amplification of total RNA from brain and ovary at gonadal recrudescent, mature ( = prespawning), and postovulatory stages resulted in two predicted sizes of PCR products. The intensities of staining signals of ethidium bromide were similar between brain and ovary samples. The same RT-PCRs were carried out with two sets of primers for cGnRH-II precursor cDNA, resulting in two PCR products of predicted size; however, the ethidium bromide staining signals are much weaker for products amplified from ovarian cDNA than that from brain cDNA. Restriction enzyme analysis verified the expected RT-PCR products. Sequence analysis of ovarian sGnRH precursor cDNA generated by RACE of total RNA from recrudescent ovarian tissue revealed the identical sequence to that of the brain sGnRH cDNA. Northern blot analysis detected a single mRNA transcript of approximately 650 bases for the sGnRH precursor in both the brain and ovary, and 750 bases for the cGnRH-II precursor in the brain. These results demonstrate that two forms of GnRH precursor (sGnRH and cGnRH-II) mRNA are expressed in goldfish brain tissue and that the sGnRH transcript and a

  8. Deletion of Vax1 from Gonadotropin-Releasing Hormone (GnRH) Neurons Abolishes GnRH Expression and Leads to Hypogonadism and Infertility.

    Science.gov (United States)

    Hoffmann, Hanne M; Trang, Crystal; Gong, Ping; Kimura, Ikuo; Pandolfi, Erica C; Mellon, Pamela L

    2016-03-23

    Hypothalamic gonadotropin-releasing hormone (GnRH) neurons are at the apex of the hypothalamic-pituitary-gonadal axis that regulates mammalian fertility. Herein we demonstrate a critical role for the homeodomain transcription factor ventral anterior homeobox 1 (VAX1) in GnRH neuron maturation and show that Vax1 deletion from GnRH neurons leads to complete infertility in males and females. Specifically, global Vax1 knock-out embryos had normal numbers of GnRH neurons at 13 d of gestation, but no GnRH staining was detected by embryonic day 17. To identify the role of VAX1 specifically in GnRH neuron development,Vax1(flox)mice were generated and lineage tracing performed in Vax1(flox/flox):GnRH(cre):RosaLacZ mice. This identified VAX1 as essential for maintaining expression of Gnrh1 The absence of GnRH staining in adult Vax1(flox/flox):GnRH(cre)mice led to delayed puberty, hypogonadism, and infertility. To address the mechanism by which VAX1 maintains Gnrh1 transcription, the capacity of VAX1 to regulate Gnrh1 transcription was evaluated in the GnRH cell lines GN11 and GT1-7. As determined by luciferase and electrophoretic mobility shift assays, we found VAX1 to be a direct activator of the GnRH promoter through binding to four ATTA sites in the GnRH enhancer (E1) and proximal promoter (P), and able to compete with the homeoprotein SIX6 for occupation of the identified ATTA sites in the GnRH promoter. We conclude that VAX1 is expressed in GnRH neurons where it is required for GnRH neuron expression of GnRH and maintenance of fertility in mice. Infertility classified as idiopathic hypogonadotropic hypogonadism (IHH) is characterized by delayed or absent sexual maturation and low sex steroid levels due to alterations in neuroendocrine control of the hypothalamic-pituitary-gonadal axis. The incidence of IHH is 1-10 cases per 100,000 births. Although extensive efforts have been invested in identifying genes giving rise to IHH, >50% of cases have unknown genetic origins

  9. Computer simulation of the free energy of peptides with the local states method: analogues of gonadotropin releasing hormone in the random coil and stable states.

    Science.gov (United States)

    Meirovitch, H; Koerber, S C; Rivier, J E; Hagler, A T

    1994-07-01

    The Helmholtz free energy F (rather than the energy) is the correct criterion for stability; therefore, calculation of F is important for peptides and proteins that can populate a large number of metastable states. The local states (LS) method proposed by H. Meirovitch [(1977) Chemical Physics Letters, Vol. 45, p. 389] enables one to obtain upper and lower bounds of the conformational free energy, FB (b,l) and FA (b,l), respectively, from molecular dynamics (MD) or Monte Carlo samples. The correlation parameter b is the number of consecutive dihedral or valence angles along the chain that are taken into account explicitly. The continuum angles are approximated by a discretization parameter l; the larger are b and l, the better the approximations; while FA can be estimated efficiently, it is more difficult to estimate FB. The method is further developed here by applying it to MD trajectories of a relatively large molecule (188 atoms), the potent "Asp4-Dpr10" antagonist [cyclo(4/10)-(Ac-delta 3Pro1-D-pFPhe2-D-Trp3-Asp4-Tyr5-D-Nal6-Leu7-Arg8 -Pro9- Dpr10-NH2)] of gonadotropin releasing hormone (GnRH). The molecule was simulated in vacuo at T = 300 K in two conformational states, previously investigated [J. Rizo et al. Journal of the American Chemical Society, (1992) Vol. 114, p. 2860], which differ by the orientation of the N-terminal tail, above (tail up, TU) and below (tail down, TD) the cyclic heptapeptide ring. As in previous applications of the LS method, we have found the following: (1) While FA is a crude approximation for the correct F, results for the difference, delta FA = FA (TD)-FA (TU) converge rapidly to 5.6 (1) kcal/mole as the approximation is improved (i.e., as b and l are increased), which suggests that this is the correct value for delta F; therefore TD is more stable than TU. (The corresponding difference in entropy, T delta SA = 1.3(2) kcal/mole, is equal to the value obtained by the harmonic approximation.) (2) The lowest approximation, which has

  10. Influence of a gonadotropin-releasing hormone vaccine and dietary standardized ileal digestible lysine level on growth performance and carcass quality of grower-finisher pigs.

    Science.gov (United States)

    Molist, F; Gerritsen, R; van der Aar, P; Prüst, H

    2014-11-01

    The aim of this study was to assess the effect of standardized ileal digestible (SID) Lys levels of the diet on the growth performance, carcass characteristics, and meat quality of entire males (EM), surgical castrates (SC), and males vaccinated with a gonadotropin-releasing hormone (GnRH) vaccine (GV). In total, 252 crossbred pigs were fed 6 different experimental diets consisting of 3 sexes (EM, SC, and GV pigs) and 2 dietary SID Lys levels (2008 CVB standard SID Lys recommendation [Std] or 15% extra SID Lys [+15]) according to a 3-phase feeding scheme (d 0 to 35, 35 to 70, and 70 to 105 of experiment) with 6 pens per treatment and 6 pigs per pen. To determine if dietary SID Lys could be reduced for GV males after the second vaccination, an additional dietary treatment was included (GV+15-Std). The GV males on the GV+15-Std were fed the diet with 15% extra SID Lys in the starter and grower phases and the standard SID Lys level in the finisher phase. First vaccination was administered to pigs at the start of the experiment (23.4 kg BW and 63.6 d of age), and the second vaccination occurred 6 wk before slaughter (77.2 kg BW and 126.6 d of age). Until the second vaccination, GV pigs showed a lower (P ≤ 0.05) ADFI than SC but similar to EM. After the second vaccination, GV pigs had an intermediate (P ≤ 0.05) G:F between EM and SC. The GV+15 pigs showed a better G:F (P ≤ 0.05) than GV pigs fed the GV+15-Std diet in the finisher phase. No differences in the growth rate of the pigs were observed. The SC had a greater (P ≤ 0.05) carcass weight and dressing percentage than EM and GV pigs. The GV-Std pigs had a lower (P ≤ 0.05) meat percentage and greater (P ≤ 0.05) backfat thickness than the GV+15 pigs. The GV pigs and SC fed the standard SID Lys diet had a greater (P ≤ 0.05) percentage of SFA in the subcutaneous fat than EM+15 pigs. On the other hand, SC showed the greatest (P ≤ 0.05) concentration of MUFA compared to EM and GV pigs. The SC and GV pigs

  11. Effect of gonadotropin-releasing hormone agonist therapy on body mass index and growth in girls with idiopathic central precocious puberty

    Directory of Open Access Journals (Sweden)

    Ahmet Anik

    2015-01-01

    Full Text Available Objective: The study aimed to assess the effect of gonadotropin-releasing hormone (GnRH agonist therapy on body mass index (BMI and growth in girls diagnosed with idiopathic central precocious puberty (CPP. Materials and Methods: Hospital records of 32 girls with idiopathic CPP who have been receiving GnRH agonist therapy for at least 12 months were retrospectively reviewed and auxological, clinical and laboratory parameters of the patients were recorded. BMI, body mass index standard deviation score (BMI SDS for chronological age body mass index standard deviation score (CA-BMI SDS, BMI SDS for bone age body mass index standard deviation score (BA-BMI SDS, ratios of obesity and overweight were assessed before treatment and on the 12 th month of therapy in patients diagnosed with idiopathic CPP. Results: The study comprised of 32 girls diagnosed with idiopathic CPP. BMI values showed statistically significant increase in the 1 st year of treatment (19.16 ± 2.8 vs. 20.7 ± 3.4, P = 0.001. Despite a mild increase in CA-BMI SDS in the 1 st year of treatment versus before treatment, it was no statistically significant (1.0 ± 0.8 vs. 1.1 ± 0.9, P = 0.061. However, significant increase was observed in BA-BMI SDS in the 1 st year of treatment versus before treatment (0.8 ± 0.7 vs. 0.4 ± 0.8, P < 0.001. Before treatment, 37.5% (12/32 of the patients were overweight and 21.9% (5/32 were obese, whereas in the 1 st year, 34.4% (11/32 of the patients were overweight and 31.3% were obese (P = 0.001. Conclusion: Whilst 1/3 of the cases diagnosed with idiopathic CPP were overweight and obese at the time of diagnosis, GnRH agonist therapy caused statistically significant weight gain in patients diagnosed with CPP. Therefore, these patients should be closely monitored and weight control should be provided by diet and exercise programs in the course of treatment.

  12. Photoperiod-independent changes in immunoreactive brain gonadotropin-releasing hormone (GnRH) in a free-living, tropical bird.

    Science.gov (United States)

    Moore, Ignacio T; Bentley, George E; Wotus, Cheryl; Wingfield, John C

    2006-01-01

    Timing of seasonal reproduction in high latitude vertebrates is generally regulated by photoperiodic cues. Increasing day length in the spring is associated with changes in the brain that are responsible for mediating reproductive activities. A primary example of this is the increased content of gonadotropin-releasing hormone (GnRH) in the preoptic area of the hypothalamus in birds as they enter the spring breeding season. Increased GnRH activity stimulates the release of luteinizing hormone and follicle-stimulating hormone from the anterior pituitary. These gonadotropins induce growth of the gonads and release of sex steroids which act on the brain to mediate reproductive behaviors. By contrast, seasonal breeding in the tropics can occur in the absence of significant changes in photoperiod. To our knowledge, no studies have investigated whether seasonal breeding in free-living tropical vertebrates is associated with seasonal changes in the GnRH system. We studied two populations of rufous-collared sparrows (Zonotrichia capensis) at the equator, separated by only 25 km, but with asynchronous reproductive phenologies associated with local climate and independent of photoperiodic cues. We collected brains and measured GnRH immunoreactivity (GnRH-ir) during each population's breeding and non-breeding periods. Breeding males had larger, but not more, GnRH-ir cells than non-breeding birds. The plasticity of the GnRH system was associated with local climate, such that the two populations exhibited asynchronous changes in GnRH-ir despite experiencing identical photoperiod conditions. Our results demonstrate that tropical birds can exhibit neural changes similar to those exhibited in higher latitude birds. However, these tropical populations appear to be using supplementary cues (e.g., rainfall, temperature, food availability) in a similar way to higher latitude species using an initial predictive cue (photoperiod). These results raise questions about the evolution of

  13. Effects of kisspeptin1 on electrical activity of an extrahypothalamic population of gonadotropin-releasing hormone neurons in medaka (Oryzias latipes).

    Science.gov (United States)

    Zhao, Yali; Wayne, Nancy L

    2012-01-01

    Kisspeptin (product of the kiss1 gene) is the most potent known activator of the hypothalamo-pituitary-gonadal axis. Both kiss1 and the kisspeptin receptor are highly expressed in the hypothalamus of vertebrates, and low doses of kisspeptin have a robust and long-lasting stimulatory effect on the rate of action potential firing of hypophysiotropic gonadotropin releasing hormone-1 (GnRH1) neurons in mice. Fish have multiple populations of GnRH neurons distinguished by their location in the brain and the GnRH gene that they express. GnRH3 neurons located in the terminal nerve (TN) associated with the olfactory bulb are neuromodulatory and do not play a direct role in regulating pituitary-gonadal function. In medaka fish, the electrical activity of TN-GnRH3 neurons is modulated by visual cues from conspecifics, and is thought to act as a transmitter of information from the external environment to the central nervous system. TN-GnRH3 neurons also play a role in sexual motivation and arousal states, making them an important population of neurons to study for understanding coordination of complex behaviors. We investigated the role of kisspeptin in regulating electrical activity of TN-GnRH3 neurons in adult medaka. Using electrophysiology in an intact brain preparation, we show that a relatively brief treatment with 100 nM of kisspeptin had a long-lasting stimulatory effect on the electrical activity of an extrahypothalamic population of GnRH neurons. Dose-response analysis suggests a relatively narrow activational range of this neuropeptide. Further, blocking action potential firing with tetrodotoxin and blocking synaptic transmission with a low Ca(2+)/high Mg(2+) solution inhibited the stimulatory action of kisspeptin on electrical activity, indicating that kisspeptin is acting indirectly through synaptic regulation to excite TN-GnRH3 neurons. Our findings provide a new perspective on kisspeptin's broader functions within the central nervous system, through its

  14. 76 FR 41525 - Hewlett Packard Global Parts Supply Chain, Global Product Life Cycles Management Unit Including...

    Science.gov (United States)

    2011-07-14

    ... Employment and Training Administration Hewlett Packard Global Parts Supply Chain, Global Product Life Cycles... Chain, Global Product Life Cycles Management Unit, including teleworkers reporting to Houston, Texas... Parts Supply Chain, Global Product Life Cycles Management Unit, including teleworkers reporting to...

  15. Moonstruck how lunar cycles affect life

    CERN Document Server

    Naylor, Ernest

    2015-01-01

    Throughout history, the influence of the full Moon on humans and animals has featured in folklore and myths. Yet it has become increasingly apparent that many organisms really are influenced indirectly, and in some cases directly, by the lunar cycle. Breeding behaviour among some marine animals has been demonstrated to be controlled by internal circalunar biological clocks, to the point where lunar-daily and lunar-monthly patterns of Moon-generated tides are embedded in their genes. Yet, intriguingly, Moon-related behaviours are also found in dry land and fresh water species living far beyond the influence of any tides. In Moonstruck, Ernest Naylor dismisses the myths concerning the influence of the Moon, but shows through a range of fascinating examples the remarkable real effects that we are now finding through science. He suggests that since the advent of evolution on Earth, which occurred shortly after the formation of the Moon, animals evolved adaptations to the lunar cycle, and considers whether, if Moo...

  16. Developmental plasticity and the evolution of animal complex life cycles.

    Science.gov (United States)

    Minelli, Alessandro; Fusco, Giuseppe

    2010-02-27

    Metazoan life cycles can be complex in different ways. A number of diverse phenotypes and reproductive events can sequentially occur along the cycle, and at certain stages a variety of developmental and reproductive options can be available to the animal, the choice among which depends on a combination of organismal and environmental conditions. We hypothesize that a diversity of phenotypes arranged in developmental sequence throughout an animal's life cycle may have evolved by genetic assimilation of alternative phenotypes originally triggered by environmental cues. This is supported by similarities between the developmental mechanisms mediating phenotype change and alternative phenotype determination during ontogeny and the common ecological condition that favour both forms of phenotypic variation. The comparison of transcription profiles from different developmental stages throughout a complex life cycle with those from alternative phenotypes in closely related polyphenic animals is expected to offer critical evidence upon which to evaluate our hypothesis.

  17. Irrational Beliefs, Life Cycles of a Couple and Divorce

    Science.gov (United States)

    Seyed-Hossein, Salimi; Reza, Karaminia; Seyed-Mahmoud, Mirzamani; Asiye, Ramezani; Reza, Taghavi Mohammad

    The present study assessed the relationships between irrational beliefs and the life cycles for couples that decided to divorce. One hundred and seventy eight people including 120 women and 58 males who were referred to the divorce court were requested to fill in The Irrational Beliefs Inventory. The results showed that the majority (37.1%) of the couples referred to Court were in the third part of the life cycle (raising children). Most divorced subjects had a life length between 1 to 5 years (44%). The highest mean scores of irrational beliefs (296.9) were found for the fifth part of the life cycle (retirement and death). Analysis showed couples in the fifth and third part of the life cycle had significantly higher irrational beliefs than the couples in the other parts of the life cycle. Irrational beliefs such as Anxious Over-concern, Frustrated Reaction and Helplessness for Change had the highest mean scores while, the Problem Avoiding, Emotional Irresponsibility and High Self-Expectation had the lowest mean scores.

  18. Life Cycle Development of Obesity and Its Determinants

    DEFF Research Database (Denmark)

    Cavaco, Sandra; Eriksson, Tor; Skalli, Ali

    their impacts on the probability of overweight and obesity evolves over the life cycle. As the data set includes information about the individuals’ health behaviours (smoking and physical exercise) at various ages we can also examine the impact of these at different stages of the persons’ life cycle. The data......This paper is concerned with how obesity and some of its determinants develop over individuals’ life cycles. In particular we examine empirically the role and relative importance of early life conditions (parents’ education and socioeconomic status) and individuals’ own education as adults and how...... used in the empirical analysis is from a common detailed questionnaire study carried out in six different European countries (Denmark, Finland, France, Greece, the Netherlands and the U.K.) and which was answered by about 6,000 individuals aged 50 to 65 at the time of the survey. Obesity indicators...

  19. 19th CIRP Conference on Life Cycle Engineering

    CERN Document Server

    Linke, Barbara

    2012-01-01

    The 19th CIRP Conference on Life Cycle Engineering continues a strong tradition of scientific meetings in the areas of sustainability and engineering within the community of the International Academy for Production Engineering (CIRP). The focus of the conference is to review and discuss the current developments, technology improvements, and future research directions that will allow engineers to help create green businesses and industries that are both socially responsible and economically successful.  The symposium covers a variety of relevant topics within life cycle engineering including Businesses and Organizations, Case Studies, End of Life Management, Life Cycle Design, Machine Tool Technologies for Sustainability, Manufacturing Processes, Manufacturing Systems, Methods and Tools for Sustainability, Social Sustainability, and Supply Chain Management.

  20. Life Cycle Reversal in Aurelia sp.1 (Cnidaria, Scyphozoa).

    Science.gov (United States)

    He, Jinru; Zheng, Lianming; Zhang, Wenjing; Lin, Yuanshao

    2015-01-01

    The genus Aurelia is one of the major contributors to jellyfish blooms in coastal waters, possibly due in part to hydroclimatic and anthropogenic causes, as well as their highly adaptive reproductive traits. Despite the wide plasticity of cnidarian life cycles, especially those recognized in certain Hydroza species, the known modifications of Aurelia life history were mostly restricted to its polyp stage. In this study, we document the formation of polyps directly from the ectoderm of degenerating juvenile medusae, cell masses from medusa tissue fragments, and subumbrella of living medusae. This is the first evidence for back-transformation of sexually mature medusae into polyps in Aurelia sp.1. The resulting reconstruction of the schematic life cycle of Aurelia reveals the underestimated potential of life cycle reversal in scyphozoan medusae, with possible implications for biological and ecological studies.

  1. Role of nondestructive evaluation in life cycle management

    Energy Technology Data Exchange (ETDEWEB)

    Martz, H.

    1997-12-18

    This paper provides an overview of some common NDE methods and several examples for the use of different NDE techniques throughout the life cycle of a product. NDE techniques are being used to help determine material properties, design new implants, extend the service life of aircraft, and help dispose of radioactive waste in a safe manner. It is the opinion of this author and others that the NDE community needs to work more closely with end users in the life cycle of a product to better incorporate NDE techniques. The NDE community needs to highlight the importance of NDE in the entire life-cycle process of a product by showing real costs savings to the manufacturing community.

  2. ECONOMIC EVALUATION: LIFE CYCLE OF THE NATIONAL GAMES ROAD

    Directory of Open Access Journals (Sweden)

    MRS. VIDYA NITIN PATIL

    2012-03-01

    Full Text Available In response to the growing importance of sustainable undertaking, purchasing and building, designers, consultants and pavement managers now tend to make more rational decisions than before when comparing the pros and cons of the construction, maintenance and management of various types of road pavements. Asphalt and concrete pavements offer specific advantages that need to be compared when selecting the most favorable option for long-life pavements. Financial decisions can be based on life cycle cost. Life Cycle Cost analysis is to arrive at such an economic equitable assessment of competing design alternatives and it further useful for budget planning. The paper describes life cycle cost analysis of the assets of road pavement byusing present worth method. The information regarding the user cost and vehicle operating cost as per IRC recommendation is also discussed in detail.

  3. Life Cycle Reversal in Aurelia sp.1 (Cnidaria, Scyphozoa.

    Directory of Open Access Journals (Sweden)

    Jinru He

    Full Text Available The genus Aurelia is one of the major contributors to jellyfish blooms in coastal waters, possibly due in part to hydroclimatic and anthropogenic causes, as well as their highly adaptive reproductive traits. Despite the wide plasticity of cnidarian life cycles, especially those recognized in certain Hydroza species, the known modifications of Aurelia life history were mostly restricted to its polyp stage. In this study, we document the formation of polyps directly from the ectoderm of degenerating juvenile medusae, cell masses from medusa tissue fragments, and subumbrella of living medusae. This is the first evidence for back-transformation of sexually mature medusae into polyps in Aurelia sp.1. The resulting reconstruction of the schematic life cycle of Aurelia reveals the underestimated potential of life cycle reversal in scyphozoan medusae, with possible implications for biological and ecological studies.

  4. Life Cycle and Suicidal Behavior among Women

    Directory of Open Access Journals (Sweden)

    Pablo Mendez-Bustos

    2013-01-01

    Full Text Available It is nowadays accepted that, independently of methodological issues, women commit fewer suicides than men but make more frequent attempts. Yet, female suicidal risk varies greatly along the lifetime and is linked to the most significant moments in it. A wide analysis of the existing literature was performed to provide a narrative description on the evolution of female suicidal rates from childhood to old age, considering the milestones in their life history. A detailed analysis of gender differences in suicidal behavior is key to establish preventive measures and priorities. More specific studies are needed to adapt future interventions on female suicide.

  5. Life-cycle-costs - reciprocating versus rotating compressors; Life-Cycle-Costs von Kolben- und Turbokompressoren

    Energy Technology Data Exchange (ETDEWEB)

    Cierniak, S. [HGC Hamburg Gas Consult GmbH, Hamburg (Germany). Compression Systems

    2001-11-01

    Modern natural gas compression is a very diversified business both globally and from application to application. This article provides a short and comprehensive comparison between two leading gas compression technologies. Due to fundamental differences in the technologies, a direct comparison is difficult and some generalisations must be made. It will be shown the principal benefits and disadvantages of both technologies and the impact of these characteristics to the operating costs of typical applications. Today's market is divided between centrifugal compressors driven by gas turbines and reciprocating compressors driven by electric motors or gas fuelled, spark ignited piston engines. The selection is based, in some degree, on either traditional application for the service type or a clear technological benefit over the other. Naturally there are many aspects with impact on the decision making process. One of the most important is reliability of the package (driver and compressor). Local norms, codes and regulations are a jungle, as well as diverse end user preferences, all of which have to be clarified on a case to case basis: and these have an impact on the investment price as well. Generally it can be said that with smaller size units the most important aspects are investment price and quick delivery. With larger units, life cycle costs take on a greater degree of significance in the process. (orig.)

  6. Triggering of final oocyte maturation with gonadotropin-releasing hormone agonist or human chorionic gonadotropin. Live birth after frozen-thawed embryo replacement cycles

    DEFF Research Database (Denmark)

    Griesinger, Georg; Kolibianakis, E M; Papanikolaou, E G

    2007-01-01

    . PATIENT(S): Patients under observation previously had been recruited into two concurrently performed, independent, randomized controlled trials (comparing hCG with GnRH-agonist for triggering final oocyte maturation in GnRH-antagonist multiple-dose protocols in normal responder patients) encompassing...

  7. Life cycle energy of single landed houses in Indonesia

    Energy Technology Data Exchange (ETDEWEB)

    Utama, Agya; Gheewala, Shabbir H. [The Joint Graduate School of Energy and Environment, King Mongkut' s University of Technology Thonburi, Bangkok (Thailand)

    2008-07-01

    Building enclosures contribute 10-50% of the total building cost and 14-17% of the total material mass. The direct as well as indirect influence of the enclosure materials plays an important role in the building life cycle energy. Single landed houses, the typical houses in Indonesia, have been chosen for this study. The life cycle energy of the house enclosures and energy consumed during their life spans shows intriguing results. The initial embodied energy of typical brick and clay roof enclosures is 45 GJ compared to the other typical walls and roof material (cement based) which is 46 GJ. However, over the 40 years life span of the houses, the clay based ones have a better energy performance than the cement based ones, 692 GJ versus 733 GJ, respectively. The material selection during the design phase is thus crucial since the buildings have at least 40-50 years' life span. (author)

  8. Life cycle assessment part 2: current impact assessment practice.

    Science.gov (United States)

    Pennington, D W; Potting, J; Finnveden, G; Lindeijer, E; Jolliet, O; Rydberg, T; Rebitzer, G

    2004-07-01

    Providing our society with goods and services contributes to a wide range of environmental impacts. Waste generation, emissions and the consumption of resources occur at many stages in a product's life cycle-from raw material extraction, energy acquisition, production and manufacturing, use, reuse, recycling, through to ultimate disposal. These all contribute to impacts such as climate change, stratospheric ozone depletion, photooxidant formation (smog), eutrophication, acidification, toxicological stress on human health and ecosystems, the depletion of resources and noise-among others. The need exists to address these product-related contributions more holistically and in an integrated manner, providing complimentary insights to those of regulatory/process-oriented methodologies. A previous article (Part 1, Rebitzer et al., 2004) outlined how to define and model a product's life cycle in current practice, as well as the methods and tools that are available for compiling the associated waste, emissions and resource consumption data into a life cycle inventory. This article highlights how practitioners and researchers from many domains have come together to provide indicators for the different impacts attributable to products in the life cycle impact assessment (LCIA) phase of life cycle assessment (LCA).

  9. Geothermal activity helps life survive glacial cycles.

    Science.gov (United States)

    Fraser, Ceridwen I; Terauds, Aleks; Smellie, John; Convey, Peter; Chown, Steven L

    2014-04-15

    Climate change has played a critical role in the evolution and structure of Earth's biodiversity. Geothermal activity, which can maintain ice-free terrain in glaciated regions, provides a tantalizing solution to the question of how diverse life can survive glaciations. No comprehensive assessment of this "geothermal glacial refugia" hypothesis has yet been undertaken, but Antarctica provides a unique setting for doing so. The continent has experienced repeated glaciations that most models indicate blanketed the continent in ice, yet many Antarctic species appear to have evolved in almost total isolation for millions of years, and hence must have persisted in situ throughout. How could terrestrial species have survived extreme glaciation events on the continent? Under a hypothesis of geothermal glacial refugia and subsequent recolonization of nongeothermal regions, we would expect to find greater contemporary diversity close to geothermal sites than in nongeothermal regions, and significant nestedness by distance of this diversity. We used spatial modeling approaches and the most comprehensive, validated terrestrial biodiversity dataset yet created for Antarctica to assess spatial patterns of diversity on the continent. Models clearly support our hypothesis, indicating that geothermally active regions have played a key role in structuring biodiversity patterns in Antarctica. These results provide critical insights into the evolutionary importance of geothermal refugia and the history of Antarctic species.

  10. Life cycle perspective of plastic recycling

    Energy Technology Data Exchange (ETDEWEB)

    Ballhorn, R. [Targeted Research on Waste Minimization and Recycling Project, Darmstadt (Germany)

    2001-07-01

    Some recent European Union directives on recycling plastics are discussed, with particular reference to the automobile industry, highlighting developing chemical technologies such as selective solution/precipitation approaches, to increase the fraction of high quality recyclates. Some promising technologies, including separation by tribo-electrical charging, sorting by optical means, separation by gasification, dissolution, hydrogenation and co-processing with heavy oil residues are described, with examples involving the conversion of mixed plastic waste by gasification, and the production of PA6 monomer from carpet waste. Conclusion based on study results to date indicate that with regard to 'end of life' vehicles the driving force for dismantling is the recovery of resalable parts and metal, not plastic. Technologies for dismantling are seen as relatively crude. Moreover, the large investment required to construct a full dismantling facility and the lack of a well-developed 'after market' for recycled products makes it unlikely that such a facility will be built in the near future. The most promising way to cope with the economic and ecological challenges appears to be a combination of chemical recycling and energy recovery, accompanied by an aggressive effort to develop the 'after market' for the recycled products. 5 refs., 9 figs.

  11. LIFE Materials: Fuel Cycle and Repository Volume 11

    Energy Technology Data Exchange (ETDEWEB)

    Shaw, H; Blink, J A

    2008-12-12

    The fusion-fission LIFE engine concept provides a path to a sustainable energy future based on safe, carbon-free nuclear power with minimal nuclear waste. The LIFE design ultimately offers many advantages over current and proposed nuclear energy technologies, and could well lead to a true worldwide nuclear energy renaissance. When compared with existing and other proposed future nuclear reactor designs, the LIFE engine exceeds alternatives in the most important measures of proliferation resistance and waste minimization. The engine needs no refueling during its lifetime. It requires no removal of fuel or fissile material generated in the LIFE engine. It leaves no weapons-attractive material at the end of life. Although there is certainly a need for additional work, all indications are that the 'back end' of the fuel cycle does not to raise any 'showstopper' issues for LIFE. Indeed, the LIFE concept has numerous benefits: (1) Per unit of electricity generated, LIFE engines would generate 20-30 times less waste (in terms of mass of heavy metal) requiring disposal in a HLW repository than does the current once-through fuel cycle. (2) Although there may be advanced fuel cycles that can compete with LIFE's low mass flow of heavy metal, all such systems require reprocessing, with attendant proliferation concerns; LIFE engines can do this without enrichment or reprocessing. Moreover, none of the advanced fuel cycles can match the low transuranic content of LIFE waste. (3) The specific thermal power of LIFE waste is initially higher than that of spent LWR fuel. Nevertheless, this higher thermal load can be managed using appropriate engineering features during an interim storage period, and could be accommodated in a Yucca-Mountain-like repository by appropriate 'staging' of the emplacement of waste packages during the operational period of the repository. The planned ventilation rates for Yucca Mountain would be sufficient for LIFE waste

  12. Early-Life Origins of Life-Cycle Well-Being: Research and Policy Implications

    Science.gov (United States)

    Currie, Janet; Rossin-Slater, Maya

    2015-01-01

    Mounting evidence across different disciplines suggests that early-life conditions can have consequences on individual outcomes throughout the life cycle. Relative to other developed countries, the United States fares poorly on standard indicators of early-life health, and this disadvantage may have profound consequences not only for population…

  13. Animal Life Cycles. Animal Life in Action[TM]. Schlessinger Science Library. [Videotape].

    Science.gov (United States)

    2000

    This 23-minute videotape for grades 5-8, presents the myriad of animal life that exists on the planet. Students can view and perform experiments and investigations that help explain animal traits and habits. The stages of life that animals pass through--birth, growth, maturation, reproduction, and death--make up the life cycle. Students learn…

  14. Life cycle assessment and life cycle costs for pre-disaster waste management systems.

    Science.gov (United States)

    Wakabayashi, Yohei; Peii, Tsai; Tabata, Tomohiro; Saeki, Takashi

    2017-10-01

    This study develops a method of environmental and economic evaluation of an integrated disaster waste management system that considers the spatial scale of removal, transport, and treatment of disaster waste. A case study was conducted on combustibles, which is a type of disaster waste derived from dwellings, in Mie Prefecture, Japan. First, we calculated the quantity and the spatial distribution of disaster waste derived from dwellings and tsunami debris produced as a result of a large-scale earthquake. The quantity of disaster waste was estimated as 7,178,000t with functioning flood-preventing facilities and 11,956,000t without functioning flood prevention facilities. Ensuring resilience in the face of earthquakes and tsunamis by renovating flood-preventing facilities is extremely important in decreasing the production of wastes, especially in coastal regions. Next, the transportation network for transporting combustibles in disaster waste to temporary storage sites, incineration plants, and landfill was constructed using an optimization model. The results showed that if flood-preventing facilities do not function properly, the installation of temporary incineration facilities becomes essential. Life-cycle emissions of CO2, SOx, NOx, and PM and the costs of removal, storage, and treatment of combustibles were calculated as 258,000t, 618t, 1705t, 7.9t, and 246millionUSD, respectively, in the case of functioning flood-preventing facilities. If flood-preventing facilities do not function, the quantity of environmentally unfriendly emissions and the costs increase. This result suggested the significance of renovation in order to maintain the conditions of flood-preventing facilities to decrease the environmental burden and costs as well as keep the production of disaster waste at a minimum. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. From life cycle assessment to sustainable production: Status and perspectives

    DEFF Research Database (Denmark)

    Hauschild, Michael Zwicky; Jeswiet, Jack; Alting, Leo

    2005-01-01

    The paper reviews the current state of Life Cycle Assessment (LCA) introducing the central elements of the methodology and the latest developments in assessment of the environmental, economic and social impacts along the product chain. The central role of LCA in Integrated Product Policy (IPP...... to the tools for design for disassembly. Life Cycle Engineering is defined, and a systematic hierarchy is presented for the different levels at which environmental impacts from industry can be addressed by the engineer in order to improve the eco-efficiency of the industry. The role of industry in meeting...... the sustainability challenge to our societies is discussed, and it is concluded that industry must include not only the eco-efficiency but also the product's environmental justification and the company ethics in a life cycle perspective in order to become sustainable. In the outlook it is concluded that current...

  16. EASEWASTE-life cycle modeling capabilities for waste management technologies

    DEFF Research Database (Denmark)

    Bhander, Gurbakhash Singh; Christensen, Thomas Højlund; Hauschild, Michael Zwicky

    2010-01-01

    Background, Aims and Scope The management of municipal solid waste and the associated environmental impacts are subject of growing attention in industrialized countries. EU has recently strongly emphasized the role of LCA in its waste and resource strategies. The development of sustainable solid...... waste management systems applying a life-cycle perspective requires readily understandable tools for modelling the life cycle impacts of waste management systems. The aim of the paper is to demonstrate the structure, functionalities and LCA modelling capabilities of the PC-based life cycle oriented...... waste management model EASEWASTE, developed at the Technical University of Denmark specifically to meet the needs of the waste system developer with the objective to evaluate the environmental performance of the various elements of existing or proposed solid waste management systems. Materials...

  17. Assessing environmental impacts in a life cycle perspective

    DEFF Research Database (Denmark)

    Hauschild, Michael Zwicky

    2005-01-01

    What are the environmental impacts from an armchairor a cellular phone or a steak, if you take into account all the activities needed to produce, maintain, use or consume and eventually dispose of it? Life cycle impact assessment is the part of life cycle assessment (LCA) where the inventory...... of material flows in the life cycle of a product are translated into environmental impacts and consumption of resources, and questions like these are given an answer. The environmental impacts may range from very local (e.g. land use) to global (like climate change). As an environmental analysis tool, LCA...... is focused on the product system which comprises all the processes which the product and its components meet throughout their lives- from the extraction of raw materials via manufacture, use and waste management to final disposal, or in short from the cradle to the grave (see Figure 1). The focus...

  18. Industrial open source solutions for product life cycle management

    Directory of Open Access Journals (Sweden)

    Jaime Campos

    2014-12-01

    Full Text Available The authors go through the open source for product life cycle management (PLM and the efforts done from communities such as the open source initiative. The characteristics of the open source solutions are highlighted as well. Next, the authors go through the requirements for PLM. This is an area where more attention has been given as the manufacturers are competing with the quality and life cycle costs of their products. Especially, the need of companies to try to get a strong position in providing services for their products and thus to make themselves less vulnerable to changes in the market has led to high interest in product life cycle simulation. The potential of applying semantic data management to solve these problems discussed in the light of recent developments. In addition, a basic roadmap is presented as to how the above-described problems could be tackled with open software solutions.

  19. Oil Points - Life Cycle Evaluations without the Data Problem

    DEFF Research Database (Denmark)

    Bey, Niki; Lenau, Torben Anker; Larsen, Michael Holm

    1999-01-01

    Environmental aspects of products in their whole life cycle are of increasing importance in industry [1]. Therefore, several methods and tools for environmental life cycle evaluation have been developed during the last years. Formal Life Cycle Assessment (LCA), the state-of-the-art in environmental...... evaluation, usually involves the handling of a considerable amount of data in order to obtain an assessment with sufficient coverage of all potential environmental impacts of the product. Obtaining these data is very often a major obstacle in conducting an LCA. Furthermore, this data intensity results...... in an equally high time consumption.Simplified, indicator-based methods have been developed to facilitate rough evaluations in relatively short periods of time [2, 3]. Unlike complex LCA methods, which are to be used by specialists, these simplified methods can be used by product developers. However, any...

  20. Implementation of Life Cycle Assessment in Product Development

    DEFF Research Database (Denmark)

    McAloone, Timothy Charles; Hauschild, M.

    2003-01-01

    The overall aim of the paper is to provide an understanding of the environmental issues involved in the early stages of product development and the capacity of life cycle assessment techniques to address these issues. The paper aims to outline the problems for the designer in evaluating......, and of the opportunities for introducing environmental criteria in the design process through meeting the information requirements of the designer on the different life cycle stages, producing an in-depth understanding of the attitudes of practitioners among product developers to the subject area, and an understanding...... of possible future directions for product development. An Environmentally Conscious Design method is introduced and trade-offs are presented between design degrees of freedom and environmental solutions. Life cycle design frameworks and strategies are addressed. The paper collects experiences and ideas around...

  1. Construction of life cycle assessment software system platform

    Institute of Scientific and Technical Information of China (English)

    ZHANG Ya-ping; ZUO Yu-hui

    2007-01-01

    There has not been life cycle assessment (LCA) software applicable to China's products. To faciliate the develop-ment of LCA software system in China, we built an object-oriented LCA software system plantform based on LCA international standards ISO 14040 to ISO 14043 and the commonness of diverse products. The system includes six modules: disassembly module, data collection module, arithmetic module, drawing module, database module and control module. It evaluates all economic and environmental impacts during the whole life cycle of a product. The integrated life cycle inventory database system allows dynamic expansion, which makes the effort required for data collection reduce with the increase of the system's application. With the improvement of human environmental-awareness, the demand of environment-friendly products is increasing, and ecological design of products has become a critical part in products development. Consummation of the LCA software system will provide a powerful tool for designing and developing Chinese ecological products.

  2. Normalisation and weighting in life cycle assessment: quo vadis?

    DEFF Research Database (Denmark)

    Pizzol, Massimo; Laurent, Alexis; Sala, Serenella

    2017-01-01

    as research gaps in normalisation and weighting. Based on this information, the article wants to provide guidance to developers and practitioners. The underlying work was conducted under the umbrella of the UNEP-SETAC Life Cycle Initiative, Task Force on Cross-Cutting issues in life cycle impact assessment...... (LCIA). Methods: The empirical work consisted in (i) an online survey to investigate the perception of the LCA community regarding the scientific quality and current practice concerning normalisation and weighting; (ii) a classification followed by systematic expert-based assessment of existing methods......Purpose: Building on the rhetoric question “quo vadis?” (literally “Where are you going?”), this article critically investigates the state of the art of normalisation and weighting approaches within life cycle assessment. It aims at identifying purposes, current practises, pros and cons, as well...

  3. Inclusion of Social Aspects in Life Cycle Assessment of Products

    DEFF Research Database (Denmark)

    Dreyer, Louise Camilla

    underlying modelling of social impacts. Concrete models for inclusion of four impact categories representing fundamental labour rights violations are developed and tested in six case studies. The results of the case studies are used to evaluate the Social LCA method and the specific models for labour rights......This Industrial PhD thesis presents the development of a social life cycle assessment (LCA) method for application in life cycle management in companies. The method aims to facilitate companies to conduct business in a socially responsible manner by enabling decisions on the basis of knowledge...... about their direct and indirect social impacts throughout the life cycle of their products. The developed methodology of Social LCA consists of (1) a framework for Social LCA (2) a method to perform quantitative Social LCA (phases, steps and activities), and (3) methods and principles to develop...

  4. A framework for social life cycle impact assessment

    DEFF Research Database (Denmark)

    Dreyer, Louise Camilla; Hauschild, Michael Zwicky; Schierbeck, Jens

    2006-01-01

    conducting responsible business. (4) A new area of protection, Human dignity and Well-being, is defined and used to guide the modelling of impact chains. (5) The Universal Declaration of Human Rights serves as normative basis for Social LCA, together with local or country norms based on socio......Goal, Scope and Background. To enhance the use of life cycle assessment (LCA) as a tool in business decision-making, a methodology for Social life cycle impact assessment (LCIA) is being developed. Social LCA aims at facilitating companies to conduct business in a socially responsible manner...... by providing information about the potential social impacts on people caused by the activities in the life cycle of their product. The development of the methodology has been guided by a business perspective accepting that companies, on the one hand, have responsibility for the people affected...

  5. Life cycle assessment applied to nanomaterials in solid waste management

    DEFF Research Database (Denmark)

    Laurent, Alexis

    for assessing engineered nanoparticles. To support the impact assessment of engineered nanoparticles in the life cycle of nanoproducts and in solid waste management systems, a comprehensive review of toxicological data for nanosilver and titanium dioxide (TiO2) particles was conducted and it enabled......-observed-adverse-effect levels and effect factors applicable in risk assessment and life cycle impact assessment, respectively. The developed effect factors for TiO2 and Ag particles were applied on two simplified LCA case studies, namely the annual consumption of food containing TiO2 nanoparticles in the United Kingdom and a T...... be negligible when compared to other contributions to human health impacts in the nanoproduct life cycle. More than the results themselves, these case studies, along with the developed methodology for investigating the relationships between the physicochemical properties of the particles and their toxic effects...

  6. Implementation of Life Cycle Assessment in Product Development

    DEFF Research Database (Denmark)

    McAloone, Timothy Charles; Hauschild, M.

    2003-01-01

    The overall aim of the paper is to provide an understanding of the environmental issues involved in the early stages of product development and the capacity of life cycle assessment techniques to address these issues. The paper aims to outline the problems for the designer in evaluating......, and of the opportunities for introducing environmental criteria in the design process through meeting the information requirements of the designer on the different life cycle stages, producing an in-depth understanding of the attitudes of practitioners among product developers to the subject area, and an understanding...... of possible future directions for product development. An Environmentally Conscious Design method is introduced and trade-offs are presented between design degrees of freedom and environmental solutions. Life cycle design frameworks and strategies are addressed. The paper collects experiences and ideas around...

  7. Life cycle assessment and the agri-food chain

    DEFF Research Database (Denmark)

    Hermansen, John Erik; Nguyen, T Lan T

    2012-01-01

    Our food consumption is responsible for a major part of the environmental impact related to our total consumption. Life cycle assessment (LCA) is a product-oriented tool that can be used efficiently to identify improvement options within the food chain covering a product’s life cycle from cradle...... of resource use and emissions associated with a product’s life cycle can be aggregated into impact categories (e.g., nonrenewable energy use, land occupation, global warming, acidification, etc.) and further aggregated into overall damage impacts (e.g., impacts on biodiversity, human health, and resource...... to grave, which is very complex for many foods, and to support choices of consumption. The LCA methodology is supported by public standards and public policy measures and has proved its value in business development for more environmentally friendly products. It is an essential feature that the effects...

  8. Life cycle Analysis of Aluminum Foil Packaging Material.

    Science.gov (United States)

    El Sebaie, Olfat; Ahmed, Manal; Hussein, Ahmed; El Sharkawy, Fahmay; Samy, Manal

    2006-01-01

    A fundamental tent of life cycle analysis (LCA) is that every material product must become a waste. To choose the greener products, it is necessary to take into account their environmental impacts from cradle to grave. LCA is the tool used to measure environmental improvements. Aluminum (Al) is the third most common element found in the earth's crust, after oxygen and silicon. Al packaging foil was chosen as the material for the study with its life cycle perspective at Alexandria. The Al packaging produced from virgin and recycled Al was investigated through life cycle stages in these two production processes; primary and secondary. The aim of this study is to evaluate the environmental impact of aluminum packaging process by using life cycle analysis of its product from two different starting raw materials (virgin and recycled aluminum). The input and output materials, energy, water, natural gas consumptions, and solid waste uses in the foil industry had been analyzed in order to identify those with significant contribution to the total environmental impacts. From the survey done on the two life cycles, it was found that in environmental terms, the most important emissions from the primary process are the emission of CO(2) and perfluorocarbon (PFC) gases, which produce the greenhouse effect, and SO(2) as well as the emission of fluorides and polyaromatic hydrocarbons (PAH compounds), which are toxic to humans and the environment. On over all material balance, it was found that the ingot shares by 45% of the feed to the casthouse furnaces at Egyptian Copper Work (ECW), net production of the casthouse is 43.76% and the yield of rotary dross furnace (RDF) is 28.8%. The net production of the foil unit represents 35% of the total input to the unit. By comparing the two life cycles, it is obvious that, for water consumption, 93.5% is used in the primary cycle, while 6.5% is used in the secondary cycle. For electricity consumption, 99.3% is used in the primary cycle

  9. Life Cycle Assessment of Willow Production; Livscykelanalys av Salixproduktion

    Energy Technology Data Exchange (ETDEWEB)

    Boerjesson, Paal

    2006-05-15

    The aim of this study is to make a life cycle assessment (LCA) of willow production (Salix) based on current cultivation practices and commercial clones. The purpose is to describe the environmental impact of the different phases in the production system and identify phases which have a significant impact on the total life cycle emissions. The production of willow is assumed to take place in southern Sweden on good agricultural soils. The results show that the production of willow is an energy efficient biomass production system which gives 20 times more energy in the form of biomass than the required energy input. In comparison with cultivation of annual energy crops, such as rape and wheat, the energy balance (energy output/energy input) of willow production is more than 3 times higher. The emissions of greenhouse gases and pollutants leading to eutrophication, acidification and creation of photochemical oxidants are often 2 to 4 times lower in willow production. The phase in willow production which requires the highest energy input, some 50 %, is fertilisation. Fertilisation also causes the highest emissions, often between 50 to 80 %, of the total life cycle emissions. Thereafter comes harvesting, with about 30 % of the energy input and 7 to 15 % of the emissions (except for the emissions leading to the creation of photochemical oxidants, some 50%), followed by establishment and transportation which normally contribute to 2 to 10 % of the total life cycle emissions. A measure to efficiently reduce the life cycle emissions of willow production is through a higher efficiency in the production of commercial fertilisers including flue-gas cleaning, leading to reduced emissions, particularly of nitrous oxide (N{sub 2}O). Other alternatives are utilising nutrient-rich organic waste products, such as sewage sludge and municipal waste water as fertilisers, which are already in practice in some willow cultivations today. Changed biomass yields, transportation distances

  10. The effects of gonadotropin-releasing hormone analogues on breast cancer and ovarian function protection%GnRH类似物在乳腺癌治疗中的应用和卵巢功能保护

    Institute of Scientific and Technical Information of China (English)

    范嘉躜; 杨振宇; 曾涛

    2012-01-01

      促性腺激素释放激素(gonadotropin-releasing hormone,GnRH)类似物治疗绝经前乳腺癌具有疗效好、停药后卵巢功能可恢复的特点,已取代手术和放疗成为治疗绝经前乳腺癌的一种主要治疗手段,现主要介绍GnRH类似物在乳腺癌内分泌治疗中的应用及其卵巢功能保护作用。%  The gonadotropin-releasing hormone (GnRH) analogues for the treatment of breast cancer has the characteristic of efficacy and menstruation recovery after treatment, which has replaced surgery and radiotherapy as a main treatment approach in the treatment of patients with premenopausal breast cancer. The effects of GnRH analogues on both the endocrine treatment of breast cancer and the protection of ovarian function are reviewed.

  11. Comparison of life cycle assessment for different volume polypropylene jars

    Directory of Open Access Journals (Sweden)

    Krkić Nevena M.

    2012-01-01

    Full Text Available When deciding what packaging is the most appropriate for a product there are many factors to be considered. One of them is the impact of the packaging on environment. In this work, life cycle inventory and life cycle assessment of two different volume packagings were compared. The data were collected on the types and amounts of materials and energy consumption in the process of packaging and distribution of hand cream packed in polypropylene jars of 200 and 350 mL. Life cycle inventory (LCI and life cycle impact assessment (LCA were calculated. It was found that the total mass flow was higher for the jars of 350 mL. After analyzing individual flows, it was found that in both cycles (polypropylene jars of 200 and 350 mL,the consumption of fresh water was a dominant flow. This fresh water flow is mostly (95% consumed in the injection molding process of manufacturing jars from polypropylene granules. The LCA analysis showed no significant difference in global warming potential between different volume jars. The process that mostly affected global warming was the production of polypropylene jars from polypropylene granules by injection molding for both jar volumes. Judging by the global warming potential, there is no difference of the environmental impact between investigated jars, but considering the mass flow and water consumption, more environmental friendly were the 200 mL jars.

  12. Improving Life-Cycle Cost Management of Spacecraft Missions

    Science.gov (United States)

    Clardy, Dennon

    2010-01-01

    This presentation will explore the results of a recent NASA Life-Cycle Cost study and how project managers can use the findings and recommendations to improve planning and coordination early in the formulation cycle and avoid common pitfalls resulting in cost overruns. The typical NASA space science mission will exceed both the initial estimated and the confirmed life-cycle costs by the end of the mission. In a fixed-budget environment, these overruns translate to delays in starting or launching future missions, or in the worst case can lead to cancelled missions. Some of these overruns are due to issues outside the control of the project; others are due to the unpredictable problems (unknown unknowns) that can affect any development project. However, a recent study of life-cycle cost growth by the Discovery and New Frontiers Program Office identified a number of areas that are within the scope of project management to address. The study also found that the majority of the underlying causes for cost overruns are embedded in the project approach during the formulation and early design phases, but the actual impacts typically are not experienced until late in the project life cycle. Thus, project management focus in key areas such as integrated schedule development, management structure and contractor communications processes, heritage and technology assumptions, and operations planning, can be used to validate initial cost assumptions and set in place management processes to avoid the common pitfalls resulting in cost overruns.

  13. Life cycle, individual thrift, and the wealth of nations.

    Science.gov (United States)

    Modigliani, F

    1986-11-01

    One theory of the determinants of individual and national thrift has come to be known as the life cycle hypothesis of saving. The state of the art on the eve of the formulation of the hypothesis some 30 years ago is reviewed. Then the theoretical foundations of the model in its original formulation and later amendment are set forth, calling attention to various implications, some distinctive to it and some counterintuitive. A number of crucial empirical tests, both at the individual and the aggregate level, are presented as well as some applications of the life cycle hypothesis of saving to current policy issues.

  14. Structural considerations for a software life cycle dynamic simulation model

    Science.gov (United States)

    Tausworthe, R. C.; Mckenzie, M.; Lin, C. Y.

    1983-01-01

    This paper presents the results of a preliminary study into the prospects for simulating the software implementation and maintenance life cycle process, with the aim of producing a computerized tool for use by management and software engineering personnel in project planning, tradeoff studies involving product, environmental, situational, and technological factors, and training. The approach taken is the modular application of a 'flow of resource' concept to the systems dynamics simulation modeling technique. The software life cycle process is represented as a number of stochastic, time-varying, interacting work tasks that each achieves one of the project milestones. Each task is characterized by the item produced, the personnel applied, and the budgetary profile.

  15. Life Cycle Assessment of the wind farm alpha ventus

    Directory of Open Access Journals (Sweden)

    Wagner H.-J.

    2013-06-01

    Full Text Available Life Cycle Assessments (LCA is an important tool for industry and policy makers, used to determine the actual emissions of a product or technology throughout its whole life cycle. In case of energy production systems or power plants, analysis of energy required to produce the materials and processes; emissions resulting from various processes for materials production and processes resulting into their Cumulated Energy Demand (CED and Global Warming Potential (GWP become important parameters when making decisions on further research, development and deployment of any technology. The method of carrying out such analysis is explained through a case study.

  16. Life Cycle Assessment in the Cereal and Derived Products Sector

    DEFF Research Database (Denmark)

    Bacenetti, Jacopo; Benedetto, Graziella; Fusi, Alessandra

    2015-01-01

    environmental improvement in such systems. Following a brief introduction to the cereal sector and supply chain, this chapter reviews some of the current cereal-based life cycle thinking literature, with a particular emphasis on LCA. Next, an analysis of the LCA methodological issues emerging from...... of the main hot spots in the cereal supply chain.......This chapter discusses the application of life cycle assessment methodologies to rice, wheat, corn and some of their derived products. Cereal product systems are vital for the production of commodities of worldwide importance that entail particular environmental hot spots originating from...

  17. Life cycle assessments of energy from solid waste

    Energy Technology Data Exchange (ETDEWEB)

    Finnveden, Goeran; Johansson, Jessica; Lind, Per; Moberg, Aasa [Stockholm Univ. (Sweden). Dept. of Systems Ecology/Natural Resoruces Management Inst.]|[Defence Research Establishment, Stockholm (Sweden). Div. of Defence Analysis

    2000-09-01

    The overall aim of the present study is to evaluate different strategies for treatment of solid waste based on a life-cycle perspective. Important goals are to identify advantages and disadvantages of different methods for treatment of solid waste, and to identify critical factors in the systems, including the background systems, which may significantly influence the results. Included in the study are landfilling, incineration, recycling, digestion and composting. The waste fractions considered are the combustible and recyclable or compostable fractions of municipal solid waste. The methodology used is Life Cycle Assessment. The results can be used for policy decisions as well as strategic decisions on waste management systems.

  18. Normalisation and weighting in life cycle assessment: quo vadis?

    DEFF Research Database (Denmark)

    Pizzol, Massimo; Laurent, Alexis; Sala, Serenella

    2017-01-01

    as research gaps in normalisation and weighting. Based on this information, the article wants to provide guidance to developers and practitioners. The underlying work was conducted under the umbrella of the UNEP-SETAC Life Cycle Initiative, Task Force on Cross-Cutting issues in life cycle impact assessment...... for normalisation and weighting according to a set of five criteria: scientific robustness, documentation, coverage, uncertainty and complexity. Results and discussion: The survey results showed that normalised results and weighting scores are perceived as relevant for decision-making, but further development...... as well as to developers of the underlying methods....

  19. An Overview of Biodiesel and Petroleum Diesel Life Cycles

    Energy Technology Data Exchange (ETDEWEB)

    Sheehan, John [National Renewable Energy Lab. (NREL), Golden, CO (United States); Camobreco, Vince [National Renewable Energy Lab. (NREL), Golden, CO (United States); Duffield, James [National Renewable Energy Lab. (NREL), Golden, CO (United States); Graboski, Michael [National Renewable Energy Lab. (NREL), Golden, CO (United States); Shapouri, Housein [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    1998-05-01

    This overview is extracted from a detailed, comprehensive report entitled Life Cycle Inventories of Biodiesel and Petroleum Diesel for Use in an Urban Bus. This report presents the findings from a study of the life cycle inventories (LCIs) for petroleum diesel and biodiesel. An LCI comprehensively quantifies all the energy and environmental flows associated with a product from “cradle to grave.” It provides information on raw materials extracted from the environment; energy resources consumed; and air, water, and solid waste emissions generated.

  20. Analysis within the systems development life-cycle

    CERN Document Server

    Rock-Evans, Rosemary

    1987-01-01

    Analysis within the Systems Development Life-Cycle: Book 4, Activity Analysis-The Methods describes the techniques and concepts for carrying out activity analysis within the systems development life-cycle. Reference is made to the deliverables of data analysis and more than one method of analysis, each a viable alternative to the other, are discussed. The """"bottom-up"""" and """"top-down"""" methods are highlighted. Comprised of seven chapters, this book illustrates how dependent data and activities are on each other. This point is especially brought home when the task of inventing new busin

  1. PRODUCT DATA PREDICTION WITH UNCERTAINTY IN PRODUCT LIFE CYCLE DESIGN

    Institute of Scientific and Technical Information of China (English)

    Yu Suiran; Wang Chengtao; Kimura Fumihiko

    2003-01-01

    Various kinds of data are used in new product design and more accurate data make the design results more reliable. Even though part of product data can be available directly from the existing similar products, there still leaves a great deal of data unavailable. This makes data prediction a valuable work. A method that can predict data of product under development based on the existing similar products is proposed. Fuzzy theory is used to deal with the uncertainties in data prediction process. The proposed method can be used in life cycle design, life cycle assessment (LCA) etc. Case study on current refrigerator is used as a demonstration example.

  2. The study of the life cycle of technology assessment model

    Institute of Scientific and Technical Information of China (English)

    SHEN Yu-Zhi; HUANG Xun-jiang

    2001-01-01

    The life cycle of technology is one of the most important indexes to weigh up the risk of the investment to neo-tech. There are so many uncertainties because it is conditioned by a lot of factors, we can not make a rational forecasting by traditional assessment method. So this paper gives a conprehensive consideration to the factors that influence production and makes some modification to production function, and establishes the life cycle of technology assessmet model by the method of fuzzy mathematics. So it quantifies the risk of investment. We can take it as one foundational index for the decision making of the investment.

  3. Life cycle assessment of capital goods related to waste incineration

    DEFF Research Database (Denmark)

    Brogaard, Line Kai-Sørensen; Christensen, Thomas Højlund

    2011-01-01

    , maintenance and demolition of capital goods. Capital goods are defined as buildings, machinery, trucks and infrastructure at the facility. A LCA was performed using two modelling programmes: Simapro and EASEWASTE. This paper assesses the importance of including capital goods when performing LCAs of waste......The environmental impacts from the life cycle of products and systems were evaluated using Life Cycle Assessment (LCA) as a tool. Today most LCAs of waste management systems only considers the impacts from the operation of the system but neglects the environmental impacts from construction...

  4. Life cycle assessment of Icelandic Atlantic salmon Aquaculture

    OpenAIRE

    2011-01-01

    This study analysed the environmental impacts of Atlantic salmon (Salmo salar) farmed in sea cages in Tálknafjörður, North West of Iceland. Methodologically the study was based on Life Cycle Assessment (LCA), and the functional unit was 1 metric tonne of the whole Atlantic salmon produced in sea cage system and delivered to a processing plant in Patreksfjörður. The life cycle model included the feed production (including feed raw materials production), hatchery, sea-cage farm, faming equipmen...

  5. Research on large equipment maintenance system in life cycle

    Science.gov (United States)

    Xu, Xiaowei; Wang, Hongxia; Liu, Zhenxing; Zhang, Nan

    2017-06-01

    In order to change the current disadvantages of traditional large equipment maintenance concept, this article plans to apply the technical method of prognostics and health management to optimize equipment maintenance strategy and develop large equipment maintenance system. Combined with the maintenance procedures of various phases in life cycle, it concluded the formulation methods of maintenance program and implement plans of maintenance work. In the meantime, it takes account into the example of the dredger power system of the Waterway Bureau to establish the auxiliary platform of ship maintenance system in life cycle.

  6. MONITORED GEOLOGIC REPOSITORY LIFE CYCLE COST ESTIMATE ASSUMPTIONS DOCUMENT

    Energy Technology Data Exchange (ETDEWEB)

    R.E. Sweeney

    2001-02-08

    The purpose of this assumptions document is to provide general scope, strategy, technical basis, schedule and cost assumptions for the Monitored Geologic Repository (MGR) life cycle cost (LCC) estimate and schedule update incorporating information from the Viability Assessment (VA) , License Application Design Selection (LADS), 1999 Update to the Total System Life Cycle Cost (TSLCC) estimate and from other related and updated information. This document is intended to generally follow the assumptions outlined in the previous MGR cost estimates and as further prescribed by DOE guidance.

  7. The data life cycle applied to our own data.

    Science.gov (United States)

    Goben, Abigail; Raszewski, Rebecca

    2015-01-01

    Increased demand for data-driven decision making is driving the need for librarians to be facile with the data life cycle. This case study follows the migration of reference desk statistics from handwritten to digital format. This shift presented two opportunities: first, the availability of a nonsensitive data set to improve the librarians' understanding of data-management and statistical analysis skills, and second, the use of analytics to directly inform staffing decisions and departmental strategic goals. By working through each step of the data life cycle, library faculty explored data gathering, storage, sharing, and analysis questions.

  8. Analysis within the systems development life-cycle

    CERN Document Server

    Rock-Evans, Rosemary

    1987-01-01

    Analysis within the Systems Development Life-Cycle: Book 2, Data Analysis-The Methods describes the methods for carrying out data analysis within the systems development life-cycle and demonstrates how the results of fact gathering can be used to produce and verify the analysis deliverables. A number of alternative methods of analysis other than normalization are suggested. Comprised of seven chapters, this book shows the tasks to be carried out in the logical order of progression-preparation, collection, analysis of the existing system (which comprises the tasks of synthesis, verification, an

  9. Sustainable Nanotechnology: Through Green Methods and Life-Cycle Thinking

    Directory of Open Access Journals (Sweden)

    Rapinder Sawhney

    2010-10-01

    Full Text Available Citing the myriad applications of nanotechnology, this paper emphasizes the need to conduct “life cycle” based assessments as early in the new product development process as possible, for a better understanding of the potential environmental and human health consequences of nanomaterials over the entire life cycle of a nano-enabled product. The importance of this reasoning is further reinforced through an illustrative case study on automotive exterior body panels, which shows that the perceived environmental benefits of nano-based products in the Use stage may not adequately represent the complete picture, without examining the impacts in the other life cycle stages, particularly Materials Processing and Manufacturing. Nanomanufacturing methods often have associated environmental and human health impacts, which must be kept in perspective when evaluating nanoproducts for their “greenness.” Incorporating life-cycle thinking for making informed decisions at the product design stage, combining life cycle and risk analysis, using sustainable manufacturing practices, and employing green chemistry alternatives are seen as possible solutions.

  10. Economy Meets Environment: An Integrated Life Cycle Approach

    OpenAIRE

    Helmut Floegl; Christina Ipser; Susanne Geissler; Hildegund Mötzl; Ulrike Radosch

    2013-01-01

    The objective of the research project LEKOECOS is to quantify the environmental and economic resources consumed by a building during planning, construction and in the utilisation and operation stage. The complexity of the utilisation process over the long life span requires a calculation model with well-orchestrated normative definitions and idealisations. The presented environmental-economical model is based on the life cycle costs model LEKOS, developed by the Danube University Krems, and t...

  11. Effects of combined gonadotropin-releasing hormone agonist and growth hormone therapy on adult height in precocious puberty: a further contribution.

    Science.gov (United States)

    Pucarelli, Ida; Segni, Maria; Ortore, Massimiliano; Arcadi, Elena; Pasquino, Anna Maria

    2003-09-01

    Out of 35 girls with idiopathic central precocious puberty (CPP) treated with gonadotropin-releasing hormone agonist (GnRHa) (depot-triptorelin) at a dose of 100 microg/kg every 21 days i.m. for at least 2-3 years whose growth velocity fell below the 25th percentile for chronological age (CA), 17 received growth hormone (GH) in addition at a dose of 0.3 mg/kg/week, s.c., 6 days per week, for 2-4 years. The other 18, matched for bone age (BA), CA and duration of GnRHa treatment, who showed the same growth pattern but refused GH treatment, remained on GnRHa alone, and were used as a control group to evaluate GH efficacy. No patient was GH deficient. Both groups discontinued treatment at a comparable BA (mean +/- SD): BA 13.4 +/- 0.6 in GnRHa plus GH group vs 13.0 +/- 0.5 years in the GnRHa alone group. The 35 patients have reached adult height (i.e. growth during the preceding year was less than 1 cm, with a BA of over 15 years). Patients of the group treated with GH plus GnRHa showed an adult height (161.2 +/- 4.8 cm) significantly higher (p < 0.001) than pre-treatment predicted adult height (PAH) calculated according to tables either for accelerated girls (153.2 +/- 5.0 cm) or for average girls (148.6 +/- 4.3 cm). The adult height of the GnRH alone treated group (156.6 +/- 5.7) was not significantly higher than pre-treatment PAH if calculated on Bayley and Pinneau tables for accelerated girls (153.9 +/- 3.8 cm), whilst it remained significantly higher if calculated on tables for average girls (149.6 +/- 4.0 cm) (p < 0.001). The gain between pre-treatment PAH and final height was 8.2 +/- 4.8 cm according to tables for accelerated girls and 12.7 +/- 4.8 cm according to tables for average girls in patients treated with GH plus GnRHa; while in patients treated with GnRH alone the gain calculated between pre-treatment PAH for accelerated girls was just 2.3 +/- 2.9 cm and 7.1 +/- 2.7 cm greater than pre-treatment PAH for average girls. The difference between the gain

  12. Indicators for human toxicity in Life Cycle Impact Assessment

    DEFF Research Database (Denmark)

    Krewitt, Wolfram; Pennington, David W.; Olsen, Stig Irving

    2002-01-01

    The main objectives of this task group under SETAC-Europe’s Second Working Group on Life Cycle Impact Assessment (LCIA-WIA2) were to identify and discuss the suitability of toxicological impact measures for human health for use in characterization in LCIA. The current state of the art of defining......, as well as potency. Quantitative severity-based indicators yield measures in terms of Years of Life Lost (YOLL), Disability Adjusted Life Years (DALY), Quality Adjusted Life Years (QALY) and other similar measures. DALYs and QALYs are examples of approaches that attempt to account for both years of life...... lost (mortality) and years of impaired life (morbidity). Qualitative severity approaches tend to arrange potency-based indicators in categories, avoiding the need to quantitatively express differences in severity. Based on the proposed criteria and current state of the knowledge, toxicological potency...

  13. The life cycle and life span of Namibian fairy circles.

    Science.gov (United States)

    Tschinkel, Walter R

    2012-01-01

    In Namibia of southwestern Africa, the sparse grasslands that develop on deep sandy soils under rainfall between 50 and 100 mm per annum are punctuated by thousands of quasi-circular bare spots, usually surrounded by a ring of taller grass. The causes of these so-called "fairy circles" are unknown, although a number of hypotheses have been proposed. This paper provides a more complete description of the variation in size, density and attributes of fairy circles in a range of soil types and situations. Circles are not permanent; their vegetative and physical attributes allow them to be arranged into a life history sequence in which circles appear (birth), develop (mature) and become revegetated (die). Occasionally, they also enlarge. The appearance and disappearance of circles was confirmed from satellite images taken 4 years apart (2004, 2008). The frequency of births and deaths as a fraction of the total population of circles allowed the calculation of an approximate turnover rate, and from this, an estimate of circle lifespan. Lifespan appeared to vary with circle size, with small circles averaging about 24 years, and larger ones 43-75 years. Overall lifespan averaged about 41 yr. A second, independent estimate of lifespan was made by revisiting circles 2 to 9 years after their clear status had been confirmed. This resulted in a lifespan estimate of about 60 years. Any causal explanation of fairy circles must include their birth, development and death, their mean lifespan and the variation of their features under different conditions.

  14. The life cycle and life span of Namibian fairy circles.

    Directory of Open Access Journals (Sweden)

    Walter R Tschinkel

    Full Text Available In Namibia of southwestern Africa, the sparse grasslands that develop on deep sandy soils under rainfall between 50 and 100 mm per annum are punctuated by thousands of quasi-circular bare spots, usually surrounded by a ring of taller grass. The causes of these so-called "fairy circles" are unknown, although a number of hypotheses have been proposed. This paper provides a more complete description of the variation in size, density and attributes of fairy circles in a range of soil types and situations. Circles are not permanent; their vegetative and physical attributes allow them to be arranged into a life history sequence in which circles appear (birth, develop (mature and become revegetated (die. Occasionally, they also enlarge. The appearance and disappearance of circles was confirmed from satellite images taken 4 years apart (2004, 2008. The frequency of births and deaths as a fraction of the total population of circles allowed the calculation of an approximate turnover rate, and from this, an estimate of circle lifespan. Lifespan appeared to vary with circle size, with small circles averaging about 24 years, and larger ones 43-75 years. Overall lifespan averaged about 41 yr. A second, independent estimate of lifespan was made by revisiting circles 2 to 9 years after their clear status had been confirmed. This resulted in a lifespan estimate of about 60 years. Any causal explanation of fairy circles must include their birth, development and death, their mean lifespan and the variation of their features under different conditions.

  15. A Robust Hybrid Zn-Battery with Ultralong Cycle Life.

    Science.gov (United States)

    Li, Bing; Quan, Junye; Loh, Adeline; Chai, Jianwei; Chen, Ye; Tan, Chaoliang; Ge, Xiaoming; Hor, T S Andy; Liu, Zhaolin; Zhang, Hua; Zong, Yun

    2017-01-11

    Advanced batteries with long cycle life and capable of harnessing more energies from multiple electrochemical reactions are both fundamentally interesting and practically attractive. Herein, we report a robust hybrid zinc-battery that makes use of transition-metal-based redox reaction (M-O-OH → M-O, M = Ni and Co) and oxygen reduction reaction (ORR) to deliver more electrochemical energies of comparably higher voltage with much longer cycle life. The hybrid battery was constructed using an integrated electrode of NiCo2O4 nanowire arrays grown on carbon-coated nickel foam, coupled with a zinc plate anode in alkaline electrolyte. Benefitted from the M-O/M-O-OH redox reactions and rich ORR active sites in NiCo2O4, the battery has concurrently exhibited high working voltage (by M-O-OH → M-O) and high energy density (by ORR). The good oxygen evolution reaction (OER) activity of the electrode and the reversible M-O ↔ M-O-OH reactions also enabled smooth recharging of the batteries, leading to excellent cycling stabilities. Impressively, the hybrid batteries maintained highly stable charge-discharge voltage profile under various testing conditions, for example, almost no change was observed over 5000 cycles at a current density of 5 mA cm(-2) after some initial stabilization. With merits of higher working voltage, high energy density, and ultralong cycle life, such hybrid batteries promise high potential for practical applications.

  16. Revisiting the life cycle of dung fungi, Including Sordaria fimicola

    Science.gov (United States)

    George Newcombe; Jason Campbell; David Griffith; Melissa Baynes; Karen Launchbaugh; Rosemary Pendleton

    2016-01-01

    Dung fungi, such as Sordaria fimicola, generally reproduce sexually with ascospores discharged from mammalian dung after passage through herbivores. Their life cycle is thought to be obligate to dung, and thus their ascospores in Quaternary sediments have been interpreted as evidence of past mammalian herbivore activity. Reports of dung fungi as endophytes would seem...

  17. Aircraft bi-level life cycle cost estimation

    NARCIS (Netherlands)

    Zhao, X.; Verhagen, W.J.C.; Curan, R.

    2015-01-01

    n an integrated aircraft design and analysis practice, Life Cycle Cost (LCC) is essential for decision making. The LCC of an aircraft is ordinarily partially estimated by emphasizing a specific cost type. However, an overview of the LCC including design and development cost, production cost, operati

  18. Life cycle assessment Part 2 : Current impact assessment practice

    NARCIS (Netherlands)

    Pennington, DW; Potting, J; Finnveden, G; Lindeijer, E; Jolliet, O; Rydberg, T; Rebitzer, G

    2004-01-01

    Providing our society with goods and services contributes to a wide range of environmental impacts. Waste generation, emissions and the consumption of resources occur at many stages in a product's life cycle-from raw material extraction, energy acquisition, production and manufacturing, use, reuse,

  19. Life cycle assessment of construction and demolition waste management

    DEFF Research Database (Denmark)

    Butera, Stefania; Christensen, Thomas Højlund; Astrup, Thomas Fruergaard

    2015-01-01

    Life cycle assessment (LCA) modelling of construction and demolition waste (C&DW) management was carried out. The functional unit was management of 1 Mg mineral, source separated C&DW, which is either utilised in road construction as a substitute for natural aggregates, or landfilled. The assessed...

  20. Life cycle impact assssment of biobased plastics from sugarcane ethanol

    NARCIS (Netherlands)

    Tsiropoulos, Ioannis; Faaij, André; Lundquist, Lars; Schenker, Urs; Biois, J.F.; Patel, M.K.

    The increasing production of bio-based plastics calls for thorough environmental assessments. Using life cycle assessment, this study compares European supply of fully bio-based high-density polyethylene and partially bio-based polyethylene terephthalate from Brazilian and Indian sugarcane ethanol

  1. Job Mobility and Earnings over the Life Cycle.

    Science.gov (United States)

    Borjas, George J.

    1981-01-01

    The prospect of a job change for any reason creates a disincentive for a worker to invest in training that is specific to the current job, and therefore those who change jobs frequently may earn less over their life cycle than those who, other things equal, seldom change jobs. (Author/CT)

  2. Life cycle impact assssment of biobased plastics from sugarcane ethanol

    NARCIS (Netherlands)

    Tsiropoulos, Ioannis; Faaij, André; Lundquist, Lars; Schenker, Urs; Biois, J.F.; Patel, M.K.

    2014-01-01

    The increasing production of bio-based plastics calls for thorough environmental assessments. Using life cycle assessment, this study compares European supply of fully bio-based high-density polyethylene and partially bio-based polyethylene terephthalate from Brazilian and Indian sugarcane ethanol w

  3. Environmentally sensitive life-cycle traits have low elasticity

    DEFF Research Database (Denmark)

    Forbes, Valery E.; Olsen, Mette; Palmqvist, Annemette

    2010-01-01

    a high sensitivity to chemical toxicants tend to have a low elasticity, meaning that changes in them have a relatively low impact on population growth rate, compared to other life-cycle traits. This makes evolutionary sense in that there should be selection against variability in population growth rate...

  4. Sustainability metrics: life cycle assessment and green design in polymers.

    Science.gov (United States)

    Tabone, Michaelangelo D; Cregg, James J; Beckman, Eric J; Landis, Amy E

    2010-11-01

    This study evaluates the efficacy of green design principles such as the "12 Principles of Green Chemistry," and the "12 Principles of Green Engineering" with respect to environmental impacts found using life cycle assessment (LCA) methodology. A case study of 12 polymers is presented, seven derived from petroleum, four derived from biological sources, and one derived from both. The environmental impacts of each polymer's production are assessed using LCA methodology standardized by the International Organization for Standardization (ISO). Each polymer is also assessed for its adherence to green design principles using metrics generated specifically for this paper. Metrics include atom economy, mass from renewable sources, biodegradability, percent recycled, distance of furthest feedstock, price, life cycle health hazards and life cycle energy use. A decision matrix is used to generate single value metrics for each polymer evaluating either adherence to green design principles or life-cycle environmental impacts. Results from this study show a qualified positive correlation between adherence to green design principles and a reduction of the environmental impacts of production. The qualification results from a disparity between biopolymers and petroleum polymers. While biopolymers rank highly in terms of green design, they exhibit relatively large environmental impacts from production. Biopolymers rank 1, 2, 3, and 4 based on green design metrics; however they rank in the middle of the LCA rankings. Polyolefins rank 1, 2, and 3 in the LCA rankings, whereas complex polymers, such as PET, PVC, and PC place at the bottom of both ranking systems.

  5. Innovative predictive maintenance concepts to improve life cycle management

    NARCIS (Netherlands)

    Tinga, T.

    2014-01-01

    For naval systems with typically long service lives, high sustainment costs and strict availability requirements, an effective and efficient life cycle management process is very important. In this paper four approaches are discussed to improve that process: physics of failure based predictive maint

  6. Life Cycle Assessment Software for Product and Process Sustainability Analysis

    Science.gov (United States)

    Vervaeke, Marina

    2012-01-01

    In recent years, life cycle assessment (LCA), a methodology for assessment of environmental impacts of products and services, has become increasingly important. This methodology is applied by decision makers in industry and policy, product developers, environmental managers, and other non-LCA specialists working on environmental issues in a wide…

  7. Life cycle assessment Part 2 : Current impact assessment practice

    NARCIS (Netherlands)

    Pennington, DW; Potting, J; Finnveden, G; Lindeijer, E; Jolliet, O; Rydberg, T; Rebitzer, G

    2004-01-01

    Providing our society with goods and services contributes to a wide range of environmental impacts. Waste generation, emissions and the consumption of resources occur at many stages in a product's life cycle-from raw material extraction, energy acquisition, production and manufacturing, use, reuse,

  8. Environmental life cycle assessment of Ethiopian rose cultivation

    NARCIS (Netherlands)

    Sahle, A.H.; Potting, J.

    2013-01-01

    A life cycle assessment (LCA) was conducted for Ethiopian rose cultivation. The LCA covered the cradle-togate production of all inputs to Ethiopian rose cultivation up to, and including transport to the Ethiopian airport. Primary data were collected about materials and resources used as inputs to, a

  9. An Examination of Operational Availability in Life Cycle Cost Models

    Science.gov (United States)

    1983-09-01

    Systems. Kenneth E. Marks, H. Garrison Massey, and Brent D. Bradley. Rand No. R-2287-AF. Santa Monica CA: The Rand Corporation, October 1978. AD...AFB OH, September 1982. AD A123045. Bryan, Noreen S.; Jacqueline J. Rosen; and Nancey T. Marland. "A New Life Cycle Cost Model: Flexible, Interactive

  10. An introduction to Life-cycle Thinking and Management

    DEFF Research Database (Denmark)

    Remmen, Arne

    This booklet descibes how enterprises can begin developing cleaner products based on a life-cycle perspective. It focuses on a simple approach to preventive environmental initiatives, where enterprises can begin at a level that matches their ambitions and their preconditions. The report is aimed...... at enterprises that, irregardless of size or sector, are interested in reducing environmental impacts from their products....

  11. DDP - a tool for life-cycle risk management

    Science.gov (United States)

    Cornford, S. L.; Feather, M. S.; Hicks, K. A.

    2001-01-01

    At JPL we have developed, and implemented, a process for achieving life-cycle risk management. This process has been embodied in a software tool and is called Defect Detection and Prevention (DDP). The DDP process can be succinctly stated as: determine where we want to be, what could get in the way and how we will get there.

  12. Life cycle assessment Part 2 : Current impact assessment practice

    NARCIS (Netherlands)

    Pennington, D.W; Potting, J; Finnveden, G; Lindeijer, E; Jolliet, O; Rydberg, T.; Rebitzer, G.

    Providing our society with goods and services contributes to a wide range of environmental impacts. Waste generation, emissions and the consumption of resources occur at many stages in a product's life cycle-from raw material extraction, energy acquisition, production and manufacturing, use, reuse,

  13. Life Cycle Assessment Software for Product and Process Sustainability Analysis

    Science.gov (United States)

    Vervaeke, Marina

    2012-01-01

    In recent years, life cycle assessment (LCA), a methodology for assessment of environmental impacts of products and services, has become increasingly important. This methodology is applied by decision makers in industry and policy, product developers, environmental managers, and other non-LCA specialists working on environmental issues in a wide…

  14. The Role of Companion Animals throughout the Family Life Cycle

    Science.gov (United States)

    Turner, Wendy G.

    2005-01-01

    This paper examines the roles that companion animals play in the lives of American families, and discusses how those roles change as families progress through the stages of the family life cycle. It highlights the importance of pets in the lives of children and the benefits they receive from such relationships. It also presents information…

  15. Analisa Life Cycle Cost pada Green Building Diamond Building Malaysia

    Directory of Open Access Journals (Sweden)

    Trixy Firsani

    2012-09-01

    Full Text Available Mengingat kenyataan bahwa seluruh emisi CO2 yang ada di dunia lebih dari sepertiganya dihasilkan oleh bangunan[1], maka dibutuhkan suatu antispasi untuk mengeliminir akan fakta tersebut, yaitu melalui penerapan suatu konsep bangunan ramah lingkungan atau biasa disebut dengan konsep green building. Salah satu bangunan yang mengadopsi konsep green building tersebut adalah Diamond Building Malaysia. Bangunan ini menghabiskan biaya yang relatif tinggi jika dibandingkan dengan biaya pada pembangunan konvensional. Namun, dengan konsep green building yang memfokuskan pada pengefisiensi energi sepanjang siklus hidup proyek, penerapan konsep tersebut tentunya akan berbalik menjadi suatu keuntungan yang berkesinambungan pada biaya operasionalnya. Oleh karena itu, perlu dilakukan suatu studi analisa Life Cycle Cost untuk melihat seberapa besar biaya yang dikeluarkan oleh suatu bangunan berkonsep green building selama periode yang ditetapkan. Dalam melakukan analisa Life Cycle Cost dibutuhkan biaya-biaya yang relevan, antara lain Biaya Awal, Biaya Operasional dan Perawatan, Biaya Energi, Biaya Penggantian, dan Nilai Sisa. Analisa dilakukan dengan menggunakan Present Worth Methode, dimana periode analisa ditentukan selama 10 tahun. Dari hasil analisa Life Cycle Cost dengan kategori biaya yang terdiri dari Biaya Awal, Biaya Energi, Biaya Operasional dan Pemeliharaan, serta Biaya Penggantian, diperoleh total biaya siklus Diamond Building Malaysia adalah sebesar RM 235.096.883atau sebesar Rp 759.290.649.000. Jika memasukkan Nilai Sisa dalam kategori biaya Life Cycle Cost tersebut, total biaya hidup Diamond Building menjadi RM 186.646.883 atau sebesar Rp 559.940.649.000.

  16. THE LIFE CYCLE OF SHOPPING CENTERS AND POSSIBLE REVITALIZATION STRATEGIES

    Directory of Open Access Journals (Sweden)

    Dabija Dan Cristian

    2009-05-01

    Full Text Available This paper addresses the concept of shopping center life cycle. The concept is considered a possible explanation for the death of certain types of shopping centers and birth of others. Of course that there are also other theories that explains this evolut

  17. Supply Chain Resilience: Assessing USAF Weapon System Life Cycle

    Science.gov (United States)

    2010-03-01

    Appendix E: Supply Chain Resilience Storyboard ........................................................... 87 Bibliography...bolt that, in March 2000, struck a Philips semiconductor plant in Albuquerque, New Mexico , created a 10-minute blaze that contaminated millions of...strategic planning of weapon systems as they mature and progress through the life cycle. 87 Appendix E: Supply Chain Resilience Storyboard 88

  18. Teaching Life Cycles: The Four-Dimensional Organism.

    Science.gov (United States)

    Harper, G. H.

    1987-01-01

    Argues that life cycles and the concept of the four-dimensional organism should be the most important idea in teaching high school biology in the United Kingdom. Presents a set of concepts and terms with a view to improving the perceived confusion in present teaching situations. (TW)

  19. Life-Cycle Costing for Training System Procurement.

    Science.gov (United States)

    Roden, Steve L.

    1984-01-01

    Discusses annual cost and present worth methods as two basic ways of calculating life-cycle cost to make purchasing decisions when replacing training systems. A training cost analysis worksheet to aid in asking comprehensive questions about training costs as they currently exist is included. (MBR)

  20. Biological catalysis of the hydrological cycle: life's thermodynamic function

    Directory of Open Access Journals (Sweden)

    K. Michaelian

    2011-01-01

    Full Text Available Darwinian theory depicts life as being overwhelmingly consumed by a fight for survival in a hostile environment. However, from a thermodynamic perspective, life is a dynamic out of equilibrium process, stabilizing and coevolving in concert with its abiotic environment. The living component of the biosphere on the surface of the Earth of greatest biomass, the plants and cyanobacteria, are involved in the transpiration of a vast amount of water. Transpiration is part of the global water cycle, and it is this cycle that distinguishes Earth from its apparently life barren neighboring planets, Venus and Mars. The dissipation of sunlight into heat by organic molecules in the biosphere and its coupling to the water cycle (as well as other abiotic processes, is by far the greatest entropy producing process occurring on Earth. Life, from this perspective, can be viewed as performing an important thermodynamic function; acting as a dynamic catalyst by aiding irreversible abiotic process such as the water cycle, hurricanes, and ocean and wind currents to produce entropy. The role of animals in this view is that of unwitting but dedicated servants of the plants and cyanobacteria, helping them to grow and to spread into initially inhospitable areas.