• Title/Summary/Keyword: Reverse cycle

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Expression of Luteinizing Hormone (LH) and Its Receptor Gene in Uterus from Cycling Rats (발정 주기중 흰쥐 자궁에서의 Luteinizing Hormone (LH)과 수용체 유전자 발현)

  • Kim, Sung-Rye;Lee, Sung-Ho
    • Clinical and Experimental Reproductive Medicine
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    • v.26 no.3
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    • pp.383-387
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    • 1999
  • Objective: There is increasing evidence for the expression of rat in gene in several extrapituitary sites including testis and ovary. We also have demonstrated that the local LH expression in the rat epididymis and uterus, the major accessory sex organs in male and female reproductive system, respectively. Design: The present study was undertaken to elucidate whether the gene for LH receptor is expressed in rat uterus and whether the expressions of uterine LH and its receptor are differentially regulated during estrous cycle. Presence of the transcripts for rat LH receptor in the rat uterine tissue were confirmed by touchdown reverse transcription-polymerase chain reaction (RT-PCR). Results: In $LH{\beta}$ semi-quantitative RT-PCR, the highest expression level was shown in estrus stage. The level of ill receptor transcripts was also fluctuated during estrous cycle. In ovariectomized rats (OVX + Oil), the expressions of both uterine LH and LH-R were markedly reduced when compared to those from normal rats. Supplement with estradiol $17{\beta}$ to the ovariectomized rats (OVX + $E_2$) restored the expression levels of LH and its receptor to the levels in uteri from normal rats. Conclusion: Our findings indicated that 1) LH and its receptor gene are expressed in the rat uterus from cycling rats, 2) the expression of uterine LH and its receptor is mainly, if not all, under the control of ovarian sex steroid(s). These results suggested that the uterine LH may act as a local regulator with auto and/or paracrine manner, though the posibility that the pituitary LH may act directly on the regulation of uterine functions could not be discarded.

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Effect of Progesterone on Expression of Prostaglandin Synthases and Plasminogen Activator in Bovine Endometrium during Estrous Cycle (발정주기의 소 자궁내막에서 Progesterone이 Prostaglandin 합성효소와 Plasminogen Activator 발현에 미치는 영향)

  • Choi, Su-Bin;Hwangbo, Yong;Cheong, Hee-Tae;Yang, Boo-Keun;Park, Choon-Keun
    • Journal of Embryo Transfer
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    • v.31 no.1
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    • pp.53-59
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    • 2016
  • This study was to investigate effect of progesterone ($P_4$) on prostaglandin (PG) synthases and plasminogen activators (PAs) system in bovine endometrium during estrous cycle. Endometrium tissues were collected from bovine uterus on follicular and luteal phase and were incubated with culture medium containing 0 (Control), 0.2, 2, 20 and 200 ng/ml $P_4$ for 24 h. The $PGF_{2{\alpha}}$ synthase (PGFS), $PGE_2$ synthase (PGES), cyclooxygenase-2 (COX-2), urokinase PA (uPA), and PA inhibitors 1 (PAI-1) mRNA in bovine endometrium were analyzed using reverse transcription PCR and PA activity was measured using spectrophotometry. In results, COX-2 was higher at 2 ng/ml $P_4$ group than control group in luteal phase (p<0.05), but, it did not change in follicular phase. Contrastively, PGES was significantly increased in 2 ng/ml $P_4$ group compared to control group in follicular phase, but there were no significant differ among the treatments in luteal phase. uPA was no significant difference between $P_4$ treatment groups and control group in both of different phase. PAI-1 was decreased in 20 ng/ml $P_4$ group compared to control group in follicular phase (p<0.05). PA activity was decreased in 2 ng/ml $P_4$ group compared to other groups in follicular and luteal phase (p<0.05). In conclusion, we suggest that $P_4$ may influence to translation and post-translation process of PG production and PA activation in bovine endometrium.

Anti-Cancer Effect of IN-2001 in MDA-MB-231 Human Breast Cancer

  • Min, Kyung-Nan;Joung, Ki-Eun;Kim, Dae-Kee;Sheen, Yhun-Yhong
    • Biomolecules & Therapeutics
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    • v.20 no.3
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    • pp.313-319
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    • 2012
  • In recent years, inhibition of HDACs has emerged as a potential strategy to reverse aberrant epigenetic changes associated with cancer, and several classes of HDAC inhibitors have been found to have potent and specific anticancer activities in preclinical studies. But their precise mechanism of action has not been elucidated. In this study, a novel synthetic inhibitor of HDAC, 3-(4-dimethylamino phenyl)-N-hydroxy-2-propenamide [IN-2001] was examined for its antitumor activity and the underlying molecular mechanisms of any such activity on human breast cancer cell lines. IN-2001 effectively inhibited cellular HDAC activity ($IC_{50}$ = 0.585 nM) inMDA-MB-231 human breast cancer cells. IN-2001 caused a significant dose-dependent inhibition of cell proliferation in estrogen receptor (ER) negative MDA-MB-231human breast cancer cells. Cell cycle analysis revealed that the growth inhibitory effects of IN-2001 might be attributed to cell cycle arrest at $G_0/G_1$ and/or $G_2$/Mphase and subsequent apoptosis in human breast cancer cells. These events are accompanied by modulating several cell cycle and apoptosis regulatory genes such as CDK inhibitors $p21^{WAF1}$ and $p27^{KIP1}$ cyclin D1, and other tumor suppressor genes such as cyclin D2. Collectively, IN-2001 inhibited cell proliferation and induced apoptosis in human breast cancer cells and these findings may provide new therapeutic approaches, combination of antiestrogen together with a HDAC inhibitor, in the hormonal therapy-resistant ER-negative breast cancers. In summary, our data suggest that this histone deacetylase inhibitor, IN-2001, is a novel promising therapeutic agent with potent antitumor effects against human breast cancers.

Effect of Pulse and Pulse-Reverse Current on Surface Morphology and Resistivity of Electrodeposited Copper (정펄스 및 역펄스 방법을 이용하여 구리 전해도금 시 전착층의 표면 형상과 고유저항에 미치는 효과)

  • Woo, Tae-Gyu;Park, Il-Song;Seol, Kyeong-Won
    • Korean Journal of Materials Research
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    • v.17 no.1
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    • pp.56-59
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    • 2007
  • Recently, requirement for the ultra thin copper foil increases with smaller and miniaturized electronic components. In this study, we evaluated the surface morphology, crystal phase ana surface roughness of the copper film electrodeposited by pulse method without using additives. Homogeneous and dense copper crystals were formed on the titanium substrate, and the optimum condition was 25% duty cycle. Moreover, the surface roughness(Ra), $0.295{\mu}m$, is the smallest value in this condition. It is thought that this copper foil is good for electromigration inhibition due to the preferential crystal growth of Cu (111)

Research Trend of an International IMS RPD Project (국제 IMS RPD 프로젝트의 연구 동향)

  • 최병욱
    • Journal of the Korean Society for Precision Engineering
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    • v.17 no.3
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    • pp.15-21
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    • 2000
  • The Intelligent Manufacturing Systems (IMS) Rapid Product Development (RPD) Project is an international partnership formed to build a pre-competitive research and development program that will address the integration of new technologies in manufacturing and provide an infrastructure for industry to cooperate much more closely in the product development cycle. In this explanatory paper, a research trend of the RPD project is briefly presented, together with its background and state-of-the-art, focusing on objectives and target results of its sub-projects which include rapid development of functional parts and tools, validation and reverse engineering, and information logistic system.

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cDNA Cloning of Farnesoic Acid-Induced Genes in Candida albicans by Differential Display Analysis

  • CHUNG SOON-CHUN;LEE JI-YOON;OH KI-BONG
    • Journal of Microbiology and Biotechnology
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    • v.15 no.5
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    • pp.1146-1151
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    • 2005
  • The yeast Candida albicans has a distinguishing feature, dimorphism, which is the ability to switch between two morphological forms: a budding yeast form and a multicellular invasive filamentous form. This ability has been postulated to contribute to the virulence of this organism. Previously, we reported that the yeast-to-hypha transition in this organism is suppressed by farnesoic acid, a morphogenic autoregulatory substance that accumulates in the medium as the cells proliferate. In this study, using a differential display reverse transcription polymerase chain reaction (DDRT-PCR) technique, we have identified several genes induced in C. albicans by farnesoic acid treatment. These observations indicate that farnesoic acid can alter the expressivity of multiple genes, including the DNA replication machinery and cell-cycle-control proteins.

Buckling and postbuckling behavior of solid superelastic shape memory alloy shafts

  • Rahman, Muhammad Ashiqur;Qiu, Jinhao;Tani, Junji
    • Structural Engineering and Mechanics
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    • v.23 no.4
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    • pp.339-352
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    • 2006
  • Observing the unique stress-strain curves of the superelastic shape memory alloy (SMA) in tension and compression, the primary intention of this study is to investigate the behavior of the shafts made of the same material, under torsional loading-unloading cycles for large angle of twist. Experiments have been performed for the superelastic SMA shafts with different unsupported lengths and angles of twist and the results are compared with those of stainless steel (SUS304) shafts under similar test conditions. As expected for the superelastic SMA, the residual strains are small enough after each cycle and consequently, the hysteresis under loading-reverse loading is much narrower than that for the SUS304. For large angle of twists, the torsional strength of the superelastic SMA increases nonlinearly and exceeds that of SUS304. Most interestingly, the slender solid superelastic SMA shafts are found to buckle when acted upon torsion for large angle of twist.

High frequency Linked Grid-Connected PV System for Residential Use (고주파링크 방식의 계통연계형 태양광발전시스템)

  • Jung, Y.S.;Yu, G.J.;Lee, S.H.
    • Proceedings of the KIEE Conference
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    • 2001.07b
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    • pp.1281-1283
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    • 2001
  • An investigation into power conditioners that interface with photovoltaic array and utilities has been completed. The rating for this investigation is residential system(3-5kW) that interface with a 220V single phase utility connection. As the result of this investigation, a 3kW high frequency PWM IGBT inverter feeding a high frequency isolation transformer with a sinusoidal current wave was selected. The output of the transformer rectified with a diode bridge rectifier four IGBT, used as 60Hz switched, reverse the polarity of the rectified current on every other half cycle of the utility voltage. Even though the high frequency link system used more power semiconductors a net size, weight, and parts cost saying result compared to the other systems due to elimination of 60Hz transformer.

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A Spirulina maxima-derived peptide inhibits HIV-1 infection in a human T cell line MT4

  • Jang, In-Seung;Park, Sun Joo
    • Fisheries and Aquatic Sciences
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    • v.19 no.9
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    • pp.37.1-37.5
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    • 2016
  • Human immunodeficiency virus (HIV) is the causative agent of acquired immune deficiency syndrome (AIDS). Anti-HIV agents targeting various steps in HIV life cycle have been developed; however, so far, no effective drugs have been found. We show here that a peptide isolated from Spirulina maxima (SM-peptide) inhibits HIV-1 infection in a human T cell line MT4. SM-peptide inhibited $HIV-1_{IIIB}$-induced cell lysis with a half-maximal inhibitory concentration ($IC_{50}$) of 0.691 mM, while its 50 % cytotoxic concentration ($CC_{50}$) was greater than 1.457 mM. Furthermore, the SM-peptide inhibited the HIV-1 reverse transcriptase activity and p24 antigen production. This suggests that SM-peptide is a novel candidate peptide, which may be developed as a therapeutic agent for acquired immunodeficiency syndrome patients.

A Study on the Si-SiO$_2$Interface Traps of the Degraded SONOSFET Nonveolatile Memories with the Charge Pumping Techniques (Charge Pumping 기술을 응용한 열화된 SONOSFET 비휘발성 기억소자의 Si-SiO$_2$ 계면트랩에 관한 연구)

  • 김주열;김선주;이성배;이상배;서광열
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1994.11a
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    • pp.59-64
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    • 1994
  • The Si-SiO$_2$interface trpas of the degraded short-channel SONOSFET memory devices were investigated using the charge pumping techniques. The degradation of devices with write/erase cycle appeared as the increase of the Si-SiO$_2$interface trap density. In order to determine the capture cross-section of the interface trap. I$\_$CP/-V$\_$GL/ characteristic curves were measured at different temperatures. Also, the spatial distributions of Si-SiO$_2$interface trap were examined by the variable-reverse bias boltage method.