• Proceedings of the Korean Society of Toxicology Conference
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• 2001.10a
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• pp.185-185
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• 2001

The CD95 (Fas, APO-1) is known to play a key role as a transmembrane cell surface receptor that mediates apoptosis of many cell types through binding with Fas ligand or cross-linking to agonistic anti-Fas antibody. Activation of CD95 provokes a potent and rapid responses in a variety of cell types by unknown mechanism.(omitted)

• Archives of Pharmacal Research
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• v.28 no.2
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• pp.142-150
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• 2005

The synthesis and structure-activity relationships of a novel series of substituted quercetins that activates peroxisome proliferator-activated receptor gamma ($PPAR{\gamma}$) are reported. The $PPAR{\gamma}$ agonistic activity of the most potent compound in this series is comparable to that of the thiazolidinedione-based antidiabetic drugs currently in clinical use.

• Bulletin of the Korean Chemical Society
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• v.31 no.6
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• pp.1501-1505
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• 2010

We report design and synthesis of the novel TRPV1 ligands through a rational approach. Simplified analogues of 12(S)-HPETE showing TRPV1 agonistic effect are disclosed. Biological evaluation revealed that substitution of functional groups without any change in conformation converted agonist into antagonist. Our work provided key information with regard to TRPV1 agonist/antagonist switching.

• Proceedings of the Korea Inteligent Information System Society Conference
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• 2005.05a
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• pp.169-185
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• 2005

신경계의 뉴런 구조는 흥분 뉴런과 억제 뉴런으로 구성되며 각각의 흥분 뉴런과 억제 뉴런은 주동근 뉴런(agonistic neuron)에 의해 활성화되며 길항근 뉴런(antagonist neuron)에 의해 비활성화 된다. 본 논문에서는 인간 신경계의 생리학적 뉴런 구조를 분석하여 퍼지 논리를 이용한 생리학적 퍼지 신경망을 제안한다. 제안된 구조는 주동근 뉴런에 의해 흥분 뉴런이 될 수 있는 뉴런들을 선택하여 흥분시켜 출력층으로 전달하고 나머지 뉴런들을 억제시켜 출력층에 전달시키지 않는다. 신경계를 기반으로 한 제안된 생리학적 퍼지 신경망의 학습구조는 입력층, 학습 데이터의 특징을 분류하는 중간층, 그리고 출력층으로 구성된다. 제안된 퍼지 신경망의 학습 및 인식 성능을 평가하기 위해 정확성이 요구되는 의학의 한 분야인 기관지 편평암 영상인식과 영상 인식의 주요 응용 분야인 차량 번호판 인식에 적용하여 기존의 신경망과 성능을 비교 분석하였다. 실험 결과에서는 제안된 생리학적 퍼지 신경망이 기존의 신경망보다 학습 시간과 수렴성이 개선되었을 뿐만 아니라, 인식에 있어서도 우수한 성능이 있음을 확인하였다.

• Translational and Clinical Pharmacology
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• v.26 no.3
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• pp.115-117
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• 2018

This tutorial explains the basic principles of mechanistic ligand-receptor interaction model, which is an operational model of agonism. A growing number of agonist drugs, especially immune oncology drugs, is currently being developed. In this tutorial, time-dependent ordinary differential equation for simple $E_{max}$ operational model of agonism was derived step by step. The differential equation could be applied in a pharmacodynamic modeling software, such as NONMEM, for use in non-steady state experiments, in which experimental data are generated while the interaction between ligand and receptor changes over time. Making the most of the non-steady state experimental data would simplify the experimental processes, and furthermore allow us to identify more detailed kinetics of a potential drug. The operational model of agonism could be useful to predict the optimal dose for agonistic drugs from in vitro and in vivo animal pharmacology experiments at the very early phase of drug development.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.135.2-135.2
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• 2003

Plasma membrane blebs are observed in many types of apoptotic cells, but their processes of formation remain to be clarified. In the present study, we investigated whether there is a relationship between change of intracellular phosphotyrosine levels and biochemical apoptotic events in Jurkat T cells undergoing apoptosis by agonistic anti-Fas antibody. When Jurkat cells were treated with Fas-antibody in the presence or absence of pretreatment with sodium orthovanadate ($Na_3${VO}_4$), a phosphotyrosine phosphatase (PTPase) inhibitor, membrane blebs disappeared in orthovanadate-treated cells. (omitted)

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.350.1-350.1
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• 2002

A series of diaralkylthiourea derivatives was prepared and tested for its antagonistic activity against vanilloid receptor. In this study we explored the possibility of selected compound type (Ⅰ) with tetrahydronaphthyl group as rigid pendant moiety. Our premise for antagonistic activity of molecules was modeled on the capsazepine. the first antagonist for vanilloid receptor. These compounds (Ⅰ) showed less potent antagonistic activity than that of capsazepine. but they were devoid of agonistic activity. (omitted)

• The Korean Journal of Pharmacology
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• v.26 no.2
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• pp.167-176
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• 1990

In the present study, we examined the effects of tamoxifen and LY117018 on various parameters for the estrogenic actions in order to understand the mechanism by which tamoxifen and LY117018 act on the uterine cells in 21-23 day old immature rats. Tamoxifen and LY117018 stimulated uterine weight and uterine contents of DNA, protein, and peroxidase activity in the absence of estradiol while inhibited above parameters in the presence of estradiol. Both cytosolic and nuclear progesterone receptors were increased by the treatment of tamoxifen and LY117018 as well as estradiol, but estradiol-induced increase in the progesterone receptors were reduced by the treatment of antiestrogens. These effects were enhanced by the multiple injections of antiestrogens. It seemed that tamoxifen was more agonistic than LY117018 but less antagonistic than LY117018, judged by their effects on various parameters for the estrogenic action. The affinities of estradiol, tamoxifen, and LY117018 for the estrogen receptor were $0.17{\pm}0.01nM(100%)$, $1.10{\pm}0.01nM(6.3%)$, and $0.23{\pm}0.01nM(77%)$, respectively. Furthermore, LY117018 was the competitive ligand for the estrogen receptor in dose-related manner but tamoxifen was not. Following estradiol treatment, nuclear estrogen receptor was sharply increased by 1 h, reaching the maximum by 16 h, while tamoxifen and LY117018 slightly increased nuclear estrogen receptor by 1 h and then decreased thereafter. It is therefore concluded that LY117018 is a competitive antagonist for the estrogen receptor with less estrogenic activity, compared to tamoxifen with low affinity to the estrogen receptor, and tamoxifen may act through other binding site than the estrogen receptor.

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.5
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• pp.707-712
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• 2011

The objective of the present study was to determine gender-related and month-related behavioral differences in captive alpine musk deer. The study was conducted at Xinglongshan Musk Deer Farm (XMDF) of Xinglongshan National Nature Reserve in Gansu Province of western China. The integrated method of focal sampling and all occurrence recording was utilized to quantify the behavioural patterns of 45 captive alpine musk deer (Moschus sifanicus) during non-mating season (from August $1^{st}$ to October $25^{th}$), and the behavioural durations of 12 behavioural patterns such as standing-gazing were recorded. The behavioural modes were compared to explore the potential differences between females and males, and the monthly behavioural modes for males and females were analyzed. Our results showed that the captive female deer in XMDF could compensate the energy lost in pregnancy, parturition and lactation through improving its ingestive efficiency. In order to be more sensitive to the changing environment, females expressed more standing-gazing (SG: $67.38{\pm}12.69\;s$) and moving (MO; $27.41{\pm}5.02\;s$), but less bedding (BE: $42.32{\pm}11.35\;s$) than male deer (SG: $56.43{\pm}9.19\;s$; MO: $19.23{\pm}4.64\;s$; BE: $96.14{\pm}15.71\;s$). Furthermore, females perform more affinitive interaction (AI: $7.89{\pm}4.81\;s$) but less ano-genital sniffing (AS: $0.24{\pm}0.13\;s$) and agonistic behaviour (CI: $0.57{\pm}0.26\;s$) than males (AI: $1.45{\pm}1.09\;s$; AS: $0.45{\pm}0.29\;s$; CI: $1.42{\pm}0.67\;s$). The females expressed ingestion more in October ($132.31{\pm}27.47\;s$) than in August ($28.80{\pm}18.44\;s$) and September ($45.1{\pm}10.84\;s$), and the males performed Ano-genital sniffing (AS: $1.79{\pm}1.14\;s$) and self-directed behaviour (SD: $12.61{\pm}5.03\;s$) significantly more in October than in August (AS: 0 s; SD: $0.62{\pm}0.17\;s$) and September (AS: $0.02{\pm}0.01\;s$; SD: $0.17{\pm}0.15\;s$). Moreover, male musk deer increased the intension of ano-genital sniffing, agonistic behaviour and tail rubbing behaviour, which were related to sexual activities.

• Development and Reproduction
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• v.20 no.4
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• pp.315-329
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• 2016

Fas ligand (FasL) and its receptor Fas have been implicated in granulosa cell apoptosis during follicular atresia. Although interferon-gamma (IFN-${\gamma}$) is believed to be involved in the regulation Fas expression in differentiated granulosa or granulosa-luteal cells, the expression of this cytokine and its role in the regulation of the granulosa cell Fas/FasL system and apoptosis during follicular maturation have not been thoroughly investigated. In the present study, we have examined the presence of IFN-${\gamma}$ in ovarian follicles at different stage of development by immunohistochemistry and related their relative intensities with follicular expression of Fas and FasL, and with differences in granulosa cell sensitivity to Fas activation by exogenous agonistic Anti-Fas monoclonal antibody (Fas mAb). Although IFN-${\gamma}$ immunostaining was detectable in oocyte and granulosa cells in antral follicles, most intense immunoreactivity for the cytokine was observed in these cells of preantral follicles. Intense immunoreactivity for IFN-${\gamma}$ was most evident in granulosa cells of atretic early antral follicles where increased Fas and FasL expression and apoptosis were also observed. Whereas low concentrations of IFN-${\gamma}$ (10-100 U/mL) significantly increased Fas expression in undifferentiated granulosa cells (from preantral or very early antral follicles) in vitro, very higher concentrations (${\geq}1,000U/mL$) were required to up-regulate of Fas in differentiated cells isolated from eCG-primed (antral) follicles. Addition of agonistic Fas mAb to cultures of granulosa cells at the two stages of differentiation and pretreated with IFN-${\gamma}$ (100 U/mL) elicited morphological and biochemical apoptotic features which were more prominent in cells not previously exposed to the gonadotropin in vivo. These findings suggested that IFN-${\gamma}$ is an important physiologic intra-ovarian regulator of follicular atresia and plays a pivotal role in regulation of expression of Fas receptor and subsequent apoptotic response in undifferentiated (or poorly differentiated) granulosa cells at an early (penultimate) stage of follicular development.