• 한국유기농업학회지
• /
• 제8권1호
• /
• pp.69-78
• /
• 1999

Three antagonistic bacterial strains against Valsa ceratosperma, one of the apple tree pathogens, were isolated from the nature and investigated. Out of the about 3,000 species of microorganisms which was isolated from the nature, the 3 strains designated as CH219, CH220 and CH245 were selected through the test of their antagonistic activity. The antagonists showed over 50% of antifungal activity against the growth of Valsa ceratosperma on PDA plates and, by the treatment of the culture broth and the heat-treated culture filtrate of it, showed over 95% of antifungal activity. When we tested on the medium which contained their culture filtrate or heat-treated culture filtrate, the antagonists strongly inhibited Valsa ceratosperma. In bioassay on the apple trees, the antagonists also showed their antifungal activity.

• Applied Biological Chemistry
• /
• 제41권6호
• /
• pp.477-482
• /
• 1998

새로운 Leukotriene $D_4$ antagonists를 찾기 위해 구조-활성간 연구를 수행하였다. 이미 알려진 chalcone 유도체의 구조와 생물학적 활성 자료를 이용하여 구조-활성간 계산을 수행한 결과 새로운 화합물을 발견하였고, 이를 합성하여 효과를 측정한 결과를 보고하고자 한다.

• 아시안잔디학회지
• /
• 제13권3호
• /
• pp.131-138
• /
• 1999

A synergistic effect of biocontrol agent and chemicals on control of the large patch on turfgrass caused by Rhizoctonia solani AG2-2 was evaluated. Chemicals; mepronil, toclofos-methyl and iprodione inhibited 90∼100% mycelial growth of R. solani AG1 and AG2-2 in vitro. While on the other, the chemicals inhibited only 0∼5%, 18∼46% and 30∼67% of mycelial growth of the antagonists, respectively. In field application, toclofos-methyl was the best to suppress the disease in single application, however, the combination of mepronil and T. viride 41D showed highest disease control effect among combinations of antagonists and chemicals. Effect of the combination of mepronil and T. viride 41D was similar to that of toclofos-methyl and T. viride 41D stage of disease development, but became higher in six week late. Results indicated that the combined application of selected antagonistic agent and chemical increased control efficasy of turgrass large patch.

• The Korean Journal of Physiology and Pharmacology
• /
• 제4권2호
• /
• pp.105-111
• /
• 2000

Stimulation of muscarinic receptors by carbachol (CCh) in the circular smooth muscle of the guinea pig gastric antrum causes muscle contraction. In the present study, muscarinic receptor subtype controlling the muscle contraction in response to CCh was studied using putative muscarinic receptor antagonists. Isometric force of the isolated circular muscle strips was measured in an organ bath. CCh contracted the muscle in a dose-dependent way, and each of the three muscarinic receptor antagonists, 4-diphenylacetoxy- N-methylpeperdine methiodide (4-DAMP), methoctramine and pirenzepine shifted the concentration- response curves to the right without significantly reducing the maximum force. The affinities of the muscarinic antagonists $(pA_2\;values)$ obtained from Schild plot analysis were 10.15, 7.05 and 6.84 for 4-DAMP, methoctramine and pirenzepine, respectively. These results suggest that the $M_3-subtype$ mainly mediate the muscle contraction in response to CCh in guinea pig gastric antrum.

• 통합자연과학논문집
• /
• 제5권2호
• /
• pp.65-71
• /
• 2012

Neuropeptide Y (NPY), a 36-amino acid polypeptide, is a member of the pancreatic polypeptide family, which consists of NPY, peptide YY (PYY) and pancreatic polypeptide (PP). The neuropeptide Y (NPY) receptors called Y receptors belongs to G-protein coupled that are involved in a variety of physiological functions such as appetite regulation, circadian rhythm and anxiety. Five receptor subtypes have been cloned in mammals (Y1, Y2, Y4, Y5, and Y6) of which four are functional. In this short review, information about the functional NYP receptors was analyzed. Sequence analyses were done between these receptors to identify the relationships between them. Phylogram was generated between these receptors to identify the close homologue between these receptors. Our sequence analyses found that Y1 and Y4 receptors are close than the other receptors. Further structure based analysis could be useful to identify subtype selective antagonists and dual antagonists targeting Y1 and Y4 receptors.

• Archives of Pharmacal Research
• /
• 제16권4호
• /
• pp.283-288
• /
• 1993

Fourteen flavonoids were evaluated for their effects as potential bradykinin (BK) antagonists. The compounds were evaluatd in several in vitro and in vivo (oral administration) systems ; inhibition of BK induced contractions in isolated rat ileum and uterus, antagonistic effects of BK induced plasma extravasation, reduction of acetic acid induced withing nociception and protection from endotoxic shock. Skullcapflavone II (3), baicalein (5), 5-methoxyflavone (11), 6-methoxyflavone (12) and 2'-methoxyflavone (14) showed effects in all the tests although the order of potency were somewhat varied.

• 대한치과보존학회:학술대회논문집
• /
• 대한치과보존학회 2003년도 제120회 추계학술대회 제 5차 한ㆍ일 치과보존학회 공동학술대회
• /
• pp.549-550
• /
• 2003

Pulpal inflammation is a kind of neurogenic inflammation and it shows vascular changes such as vasodilation and changes in vascular leakage. Various kinds of neuropeptides including substance P (SP) are known to be involved in the pulpal inflammation. The purpose of this study was to investigate the influence of NK1 receptor antagonists on the pulpal blood flow (PBF) when applied iontophoretically through the dentinal cavity of the teeth in order to understand whether iontophoretic ally applied NK1 receptor antagonists can control the pulpal inflammation.(omitted)

• 대한약학회:학술대회논문집
• /
• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
• /
• pp.355.1-355.1
• /
• 2002

Recently. we have reported that several lipoxygenases products directly activate the capsaicin-activated channel as intracellular messengers in neuron. In particular, 12-(S)-hydroperoxyeicosatetraenoic acid turned out to be the most potent endogenous VR activator. This finding prompted us to search for a novel non-vaniloid VR agonists and antagonists. We have designed and synthesized a series of non-vanilloid VR binding ligands based on the structural simllarity between 12-HPETE and capsaicin, the natural VR agonist. Our recent studies on the development of selective vanilloid receptor agonists and antagonists will be presented.

• 대한약학회:학술대회논문집
• /
• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
• /
• pp.251.1-251.1
• /
• 2002

Capsaicin and analogues are valuable analgesic agents when administered to mammals. including humans. However. their pungency. hypothermia and the effects on the cardiovascular and respiratory systems through their general activation of primary afferents severely limit their use. So competitive antagonists have been pursued as a novel pharmacological agent for analgesics. rather than agonists. We have identified a new class of potent and selective vanilloid receptor (VR) antagonists. (omitted)

• Bulletin of the Korean Chemical Society
• /
• 제17권2호
• /
• pp.182-188
• /
• 1996

Early attempts to identify plausible conformations of a linear octapeptide hormone, angiotensin-II (Asp-Arg-Val-Tyr-Ile-His-Pro-Phe), using various theoretical and experimental methods, have led to various conformational models. So far, no consensus has been made about the solution phase structure and the receptor binding structure of angiotensin-II. The ultimate goal for the conformation study of the peptide hormone is to develop a new potent drug. Therefore, we have devised a strategy for designing the pharmacophore by studying thermodynamically possible conformations of various kinds of angiotensin-II antagonists and angiotensin-II.