• Title/Summary/Keyword: Hormones

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Endocrine Disruptors in Developing Embryo on Daphnia magna

  • Kim, Pan-Gyi;Hwang, Seong-Hee
    • Journal of Environmental Health Sciences
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    • v.28 no.4
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    • pp.17-22
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    • 2002
  • In crustaceans, as in other arthropods, the molt cycle and the physiological process of growth are controlled by molting hormones (MH) which are steroid hormones, the ecdysteroids. Ecdysteroids are major arthropod hormones which control both development (embryonic and larval molts, metamorphosis) and reproduction. The purpose of the present study was to evaluate both fenarimol and methoprene for embryotoxicity to daphnids. The embryotoxicity associated with each compound was assessed to discern whether the embryotoxicity of methoprene might be due to ecdysone agonist and the ecdysone antagonistic effects of fenarimol on Daphnia embryo. Exposure of daphnids for three weeks to 50 M methoprene resulted in a significantly high incidence of offspring that exhibited general toxicity. This exposure concentration had significant effects on the overall number of embryo death. However, exposure to 3 or 1 $\mu$M fenarimol were no significant effects on the embryo toxicity. The incidence of both of these toxicity increased with methoprene exposure. This observation suggest that methoprene showed embryonic general toxicity during embryo development, while, only fenarimol showed weak general toxicity with early stages of embryonic development.

Effects of Steroid Hormones on Collagen Biosynthesis in Rat Aorta and Uterus

  • Min, Byung-Moo;Kim, Wang-Kook;Cheong, Dong-Kyun
    • The Journal of the Korean dental association
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    • v.19 no.7 s.146
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    • pp.609-614
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    • 1981
  • Effects of steroid hormones on the collagen biosynthesis in aorta and uterus were studied with ovariectomized Sprague-Dawley rats. Effects of administration of hormones, such as estrogen, testosterone and prednisolone, to the ovariectomized animals were studied, comparing with the control. Each group was injected with ³H-proline and sacrificed, followed by removals of aorta and uterus. Separations and quantitative analyses of proline and hydroxyproline were performed by means of thin layer chromatography; and radioactivities of the separated amino acids were assayed by liquid scintillation counter. Normally the incorporation of ³H-proline into hydroxyproline was greater in uterus than in aorta, and collagen turnover rate of uterus was observed rapid as well than that of aorta. In the two tissues from ovariectomized rats, the incorporation rate of ³H-proline into hydroxypoline was markedly decreased than that of the former. Changes in the turnover rate of collagen in these tissues were not observed. Decrease in ³H-proline incorporation into collagen in ovariectomized rats was markedly antagonized by estrogen, but not influenced by prednisolone in the tissues tested.

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Plant Growth and Differentiation - Concerto for Hormones, Environment and Genes - (식물의 생장과 분화 - 유전자. 홀몬. 환경의 조화 -)

  • 맹주선
    • Proceedings of the Botanical Society of Korea Conference
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    • 1987.07a
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    • pp.117-132
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    • 1987
  • Plants are inherited spatial and temporal coordination systems in their growth and differentiation processes which are precisely governed by the two interlocked control systems; autogenous and environmental. Looking into the overall course of plant development from molecular to organismal level, it can be comparable to a concerto for plant hormones, environmental stimuli and plant genomic orchestra conducted by an unidentified virtuoso. Some of the recent significant attempts to puzzle out the mystery of the life processes of plant development are briefly reviewed. The revolutionary advances in understanding the mystic processes are contemporarily achieved by the application of various molecular techniques. The characterization of plant genomes is now attained through recombinant DNA approaches, and the sensitive detection of specific gene products during the plant development is perimitted by the immunochemical procedures. However, along with the recognition of underlying molecular events such as developmental changes in gene expression and hormone-receptor interrelation associated with tissue sensitivity to hormones, more emphasis should be placed upon the physiological approaches of organismal level for the understanding the correlative systems of the developmental processes of plants as intact eukaryotic organisms.

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Reference Interval of Serum Thyroid Hormones in Healthy Korean Adults (건강한 한국인 성인의 혈청 갑상선호르몬 참고치)

  • Jang, Yoon-Young;Kim, Chang-Yoon;Hwang, Tae-Yoon;Kim, Kyung-Dong;Lee, Chae-Hoon
    • Journal of Preventive Medicine and Public Health
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    • v.41 no.2
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    • pp.128-134
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    • 2008
  • Objectives : This study was conducted to determine the reference interval of serum thyroid hormones(TSH, $FT_3$, $FT_4$) in healthy Korean adults. Methods : Health examination data from 1,591 healthy Korean adults who visited an university hospital were analyzed. Patients with specific health conditions capable of altering laboratory results were excluded from the study. Serum thyroid hormones were measured using IMMULITE 2000 (DPC, USA, 2002). Subjects were 18-65 years old; 911 were male, and 690 were female. Results : The arithmetic means of TSH, $FT_3$, and $FT_4$ values for male subjects were $1.28{\pm}1.84\;{\mu}IU/ml$, $3.23{\pm}0.57\;pg/ml$, and $1.42{\pm}0.22\;ng/dl$, respectively. In female subjects, the arithmetic means of TSH, FT3, and FT4 values were $1.49{\pm}2.08\;{\mu}IU/ml$, $3.08{\pm}0.54\;pg/ml$, and $1.29{\pm}0.24\;ng/dl$, respectively. The arithmetic mean $FT_4$ value for males decreased with age (p<0.01). The arithmetic mean $FT_3$ value for females increased with age (p<0.01). The arithmetic mean thyroid hormone values of all study subjects differed significantly based on season. The arithmetic mean of male $FT_4$ decreased with increasing BMI (p<0.01). The arithmetic mean of female $FT_3$ increased with increasing BMI (p<0.01). The reference intervals recommended by the IMMULITE 2000 manufacturer are $0.40-4.00\;{\mu}IU/ml$ for TSH, 1.80-4.20 pg/ml for $FT_3$, and 0.80-1.90 ng/dl for $FT_4$ (same values for both genders). Conclusions : There was a significant difference in the interval of thyroid hormones between males and females, but the reference interval of IMMULITE 2000 was not established by gender. There is a need to reestablish the reference interval for thyroid hormones in Korean healthy adults.

Linkage between Trade and SPS Measure through Establishment of Reasonable-Regulator Approach to Judicial Review : Focusing on US-Hormones Suspension Case (합리적 규제자 기준의 확립을 통한 무역과 위생검역조치의 조화 - US-Hormones Suspension 사건을 중심으로 -)

  • Lee, Ju-Young;Lee, Eun-Sup
    • International Commerce and Information Review
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    • v.13 no.3
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    • pp.403-431
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    • 2011
  • The environmental issues including domestic measures to protect public life or health are generally easy to bring the tension between the WTO and its member countries. The standard of review, whether de novo review, total deference, or somewhere in between, is largely important in the WTO's adjudicating mechanism because it is closely related to the appropriate balance of power between sovereign nations and the WTO: The multilateral trading regime, through the proper standard of review, could harmoniously operated without interest conflicts among the member countries and at the same time between the WTO and the member countries. Irrespective the important function of the standard of review in the WTO judicial system, applicable standard of review has not been established in the current SPS Agreement. Furthermore, the nature of the SPS Agreement related in scientific factors, such as scientific experiment, data and assessment prevents the WTO's panel from applying consistent standard of review. Considering the judicial demand for the moderate treatment of the case under the SPS Agreement, this paper explores appropriate standard of review applicable the SPS-related environmental measures, particularly, by analysing the recent SPS-related dispute, US-Hormones Suspension.

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The Reaction of Digitoxin and Digoxin with Cyanoacetic Acid Hydrazide: Synthesis of Coumarin, Thiazole, Thiophene and Pyridine Derivatives with Potential Biological Activities

  • Doss, Senot H.;Wardakhan, Wagnat W.;Louca, Nadia A.
    • Archives of Pharmacal Research
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    • v.24 no.5
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    • pp.377-384
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    • 2001
  • The reaction of either Digitoxin or Digoxin with cyanoacetic acid hydrazide gave the hydrazone derivatives 3a and 3b respectively. The reactivity of the latter products towards chemical reagents was studied to give heterocyclic derivatives with potential biological activities.

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In vitro Studies on Hormonal Regulation of Vitellogenin Synthesis in Tilapia Hepatocytes

  • Kim, Byung-Ho;Akihiro Takemura;Lee, Young-Don
    • Proceedings of the Korean Society of Fisheries Technology Conference
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    • 2002.10a
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    • pp.216-217
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    • 2002
  • Vitellogenin (VTG) is a Precursor form of egg yolk Proteins, which appear only in the blood circulation of female fish and its synthesis in the liver is considered to be regulated by several hormones. It has been reported that in addition to estradiol-17 $\beta$ (E2) several hormones are also involved in the production site of VTG, the liver (Peyon et al., 1996; Mori et al., 1998). (omitted)

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Ginseng as a Complementary and Alternative Medicine for Postmenopausal Symptoms

  • Shim, Myeong-Kuk;Lee, Young-Joo
    • Journal of Ginseng Research
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    • v.33 no.2
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    • pp.89-92
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    • 2009
  • Ginseng is a popular herbal medicine that has been used for thousands of years. A number of its components have been isolated and characterized, including ginsenosides, polysaccharides, peptides, polyacetylenic alcohols, and fatty acids. The lipophilic characteristics of ginsenosides have raised the possibility of their efficacy as steroid hormones. Several in-vitro studies have reported their pharmacological function as steroid hormones, especially estrogen, but no human study to date has confirmed their efficacy as alternatives to synthetic estrogen.

EFFECT OF ENVIRONMENTAL TEMPERATURE AND FEED INTAKE ON PLASMA CONCENTRATION OF THYROID HORMONES IN DAIRY HEIFERS

  • Purwanto, B.P.;Fujita, M.;Nishibori, M.;Yamamoto, S.
    • Asian-Australasian Journal of Animal Sciences
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    • v.4 no.3
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    • pp.293-298
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    • 1991
  • A study was conducted to determine the effect of environmental temperature and level of food intake on plasma concentration of thyroid hormones. Three dairy heifers were used in an experiment which consisted of three levels of chamber temperature (10, 20 and $30^{\circ}C$) and three levels of food intake (100, 75 and 50% of recommended requirements). The analysis showed significant effects of environmental temperature on plasma triiodothyronine concentration, rectal temperature, respiration rate and heart rate but not on heat production. The range of plasma triiodothyronine was 2.51~1.79 ng/ml when the environmental temperature varied from 10 to $30^{\circ}C$. Effects of feed intake level were significant for heart rate and heal production. Heat production decreased from 25.9 to $20.0kJ/kg^{0.75}{\cdot}h$ when the TDN intake decreased from 66.3 to $35.1g/kg^{0.75}{\cdot}d$. There was no interactive effect of environmental temperature and feed intake level. Plasma triiodothyronine concentration decreased under high environmental temperature without any changes in heat production. The effects of environmental temperature and feed intake level on the physiological function of thyroid gland, as indicated by the relative circulating rate of thyroid hormones, were found to be clear.