• 제목/요약/키워드: Activation Products

검색결과 644건 처리시간 0.024초

천연물로부터 항암면역증강물질 탐색연구 (Screening of Antineoplastic Immunomodulator from Herbal Medicines)

  • 송지영;양현옥;표석능;박신영;김기환;손은화;강남성;윤연숙
    • 약학회지
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    • 제42권2호
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    • pp.132-139
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    • 1998
  • Currently, cancer is the primary cause of death and 50% of cancer patients are incurable by surgery, radiotherapy and chemotherapy. Therefore, immunotherpy is interested as the fourth remedy. Biological response modifier (BRM), such as organometallic compounds, glycoproteins, polysaccharides and other natural products. Is the one which can enhance the immune response against cancer cell. To develop new BRM from natural sources, we investigated 63 species Korean traditional medicines by observing the mitogenic activity to splenocytes, generation of activated killer cells and activation of macrophages. Finally, we selected 9 species including Angelicae gigantis Radix, Mori Cortex Radicis, Arisaematis Tuber, Salviae Radix, Cnidii Rhizoma, Ligusti Fructus, Pasoraliae Semen, Loranthi Ramulus, Ginseng Radix. Bioassay-guided fractionation and purification is undergoing.

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Kinetics and Mechanistic Chemistry of Oxidation of Butacaine Sulfate by Chloramine-B in Acid Medium

  • Shubha, Jayachamarajapura Pranesh;Kotabagi, Vinutha;Puttaswamy, Puttaswamy
    • Bulletin of the Korean Chemical Society
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    • 제33권11호
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    • pp.3539-3543
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    • 2012
  • Butacaine sulfate is an ester of p-aminobenzoic acid which has been widely used as a local anaesthetic and it is a long standing agent particularly for spinal anaesthesia. For this reason, a kinetic study of oxidation of butacaine sulfate by sodium N-chlorobenzenesulfonamide (chloramine-B or CAB) has been carried out in $HClO_4$ medium at 303 K in order to explore this redox system mechanistic chemistry. The rate shows a first-order dependence on both $[CAB]_o$, and $[substrate]_o$, and a fractional-order dependence on acid concentration. Decrease of dielectric constant of the medium, by adding methanol, increases the rate of the reaction. Variation of ionic strength and addition of benzenesulfonamide or NaCl have no significant effect on the rate. The reaction was studied at different temperatures and the activation parameters have been evaluated. The stoichiometry of the reaction has been found to be 1:2 and the oxidation products have been identified by spectral analysis. The observed results have been explained by plausible mechanism and the related rate law has been deduced.

Kinetic and Mechanistic Studies of Oxidation of an Antiallergic Drug with Bromamine-T in Acid and Alkaline Media

  • Puttaswamy, Puttaswamy;Sukhdev, Anu
    • Bulletin of the Korean Chemical Society
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    • 제33권11호
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    • pp.3544-3550
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    • 2012
  • Cetrizine dihydrochloride (CTZH) is widely used as an anti-allergic drug. Sodium N-bromo-p-toluenesulfonamide or bromamine-T (BAT) is the bromine analogue of chloramine-T (CAT) and is found to be a better oxidizing agent than CAT. In the present research, the kinetics of oxidation of CTZH with BAT in acid and alkaline media was studied at 313 K. The experimental rate laws obtained are: -d[BAT]/dt=$k[BAT][CTZH]^{0.80}[H^+]^{-0.48}$ in acid medium and -d[BAT]/dt=$k[BAT][CTZH]^{0.48}[OH^-]^{0.52}[PTS]^{-0.40}$ in alkaline medium where PTS is p-toluenesulfonamide. Activation parameters and reaction constants were evaluated. The solvent isotope effect was studied using $D_2O$. The dielectric effect is positive. The stoichiometry of the reaction was found to be 1:1 and the oxidation products were identified as 4-chlorobenzophenone and (2-piperazin-1-yl-ethoxy)-acetic acid in both media. The rate of oxidation of CTZH is faster in acid medium. Suitable mechanisms and related rate laws have been worked out.

Ginsenoside Rd and ischemic stroke; a short review of literatures

  • Nabavi, Seyed Fazel;Sureda, Antoni;Habtemariam, Solomon;Nabavi, Seyed Mohammad
    • Journal of Ginseng Research
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    • 제39권4호
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    • pp.299-303
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    • 2015
  • Panax ginseng is a well-known economic medical plant that is widely used in Chinese traditional medicine. This species contains a unique class of natural products-ginsenosides. Recent clinical and experimental studies have presented numerous lines of evidence on the promising role of ginsenosides on different diseases including neurodegenerative diseases, cardiovascular diseases, and certain types of cancer. Nowadays, most of the attention has focused on ginsenoside Rd as a neuroprotective agent to attenuate ischemic stroke damages. Some of the evidence showed that ginsenoside Rd ameliorates ischemic stroke-induced damages through the suppression of oxidative stress and inflammation. Ginsenoside Rd can prolong neural cells' survival through the upregulation of the endogenous antioxidant system, phosphoinositide-3-kinase/AKT and extracellular signal-regulated protein kinase 1/2 pathways, preservation of mitochondrial membrane potential, suppression of the nuclear factor-kappa B, transient receptor potential melastatin, acid sensing ion channels 1a, poly(ADP-ribose) polymerase-1, protein tyrosine kinase activation, as well as reduction of cytochrome c-releasing and apoptosis-inducing factor. In the current work, we review the available reports on the promising role of ginsenoside Rd on ischemic stroke. We also discuss its chemistry, source, and the molecular mechanism underlying this effect.

$BaTiO_3$고상반응 합성시 분해 반응의 고찰 (A Study on Decomposition in Synthesis of $BaTiO_3$ by Soild-solid Reaction)

  • 김종옥;임대영
    • 자연과학논문집
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    • 제4권
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    • pp.85-93
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    • 1991
  • $BaCO_3$$TiO_2$ 등 mole비 혼합물의 고상반응은 $BaCO_3 + TiO_2\longrightarrow$ $BaTiO_3 + CO_2$의 반응식에 따라 $CO_2$ gas가 발생된다. 이 분해과정을 DTA-TG를 사용하여 속도론적으로 고찰하였다. 그 결과는 다음과 같다. 1. $TiO_2$와 공존하는 $BaCO_3$는 순수한 $BaCO_3$보다 낮은 온도에서 분해된다. 그 이유는 생성물의 free energy가 감소되기 때문이다. 2. $BaCO_3$ 분해과정의 속도론적 고찰에 사용되는 식은 Jander's식보다는 Carter's식이 더욱 의미가 있으며 Carter's식에 의해 구해진 분해 활성화 에너지는 42.8Kcal/mol이다.

스마트워크 지원기술과 산업유형 분석 연구 (A Study on the Analysis of Supporting Technologies and the Industry Types for Smart Work)

  • 노규성;유승엽;조현주
    • 디지털융복합연구
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    • 제9권4호
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    • pp.9-18
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    • 2011
  • 본 연구는 스마트워크 산업의 경쟁력 분석을 통해 스마트워크 산업증진 전략을 세우기 위해 이루어졌다. 이를 위해 스마트워크 산업지원 기술에 대한 분석을 시도하였으며, 또한 스마트워크 산업유형을 구분하였다. 연구목적을 위해 스마트워크 분야 40명의 전문가를 대상으로 전문가 심층면접을 실시하여 자료를 수집하였다. 분석결과 스마트워크 2.0 개념에 대한 타당성을 확인하였으며, 또한 스마트워크 산업에 대한 인식을 알아보았다. 연구결과 스마트워크 2.0개념은 타당성이 높게 나타났으며, 11개 스마트워크 산업군을 도출하였다. 이러한 결과를 통해 스마트워크 산업에 대한 활성화 정책을 제안하고자 하였다.

Porphyromonas gingivalis의 각종 표면성분이 싸이토카인 형성에 미치는 영향 (The cytokine-inducing activities of surface components of the periodontopathogenic bacterium Porphyromonas gingivalis)

  • 김성조
    • Journal of Periodontal and Implant Science
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    • 제35권3호
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    • pp.799-811
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    • 2005
  • This study was carried out to examine the potency of the three surface compo- nents from Porphyromonas gingivalis to stimulate the murine macrophage cell line RAW264.7 to synthesize the pro-inflammatory cytokine tumor necrosis factor alpha($TNF-{\alpha}$) and nitric oxide (NO). Lipopolysaccharide(LPS). lipid A-associated proteins(LAP) and saline-extractable surface -associated material(SAM) were isolated from P. gingivalis 381. $TNF-{\alpha}$ release into culture supernatants was determined by two-site ELISA. NO production was assayed by measuring the accumulation of nitrite in culture supernatants. Western blot analysis of iNOS and analysis of reverse transcription(RT)-PCR products were carried out. The surface components extracted from this bacterium were almost equally potent in stimulating release of $TNF-{\alpha}$ and NO by RAW264.7 cells. $TNF-{\alpha}$ that was being measured immunologically was due to activation of $TNF-{\alpha}$ gene transcription. The present study clearly shows that P. gingivalis surface components fully induced iNOS expression in RAW264.7 cells in the absence of other stimuli. The ability of P. gingivalis surface components to promote the production of $TNF-{\alpha}$ and NO may be important in the pathogenesis of inflammatory periodontal disease.

HDPE의 열분해에 의한 액화 특성 (Liquefaction Characteristics of HDPE by Pyrolysis)

  • 유홍정;이봉희;김대수
    • 폴리머
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    • 제27권1호
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    • pp.84-89
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    • 2003
  • 열분해 온도 및 열분해 시간이 HDPE의 열분해에 미치는 영향을 해석하였다. HDPE 열분해의 시작온도와 활성화에너지는 가열속도가 증가함에 따라 증가하였다. 전환율과 액체수율은 열분해 온도와 시간이 증가함에 따라 계속 증가하였고, 특히 45$0^{\circ}C$에서 열분해 시간에 매우 민감하게 변하였다. 전환율에 있어 열분해 온도가 열분해 시간보다 더 큰 영향을 주었다. 열분해 과정에서 생성된 각각의 액체성분을 한국석유품질검사소 석유제품 품질기준에 기초하여 증류온도에 따라 가솔린, 등유, 경유, 왁스로 분류하여 본 결과, 450 $^{\circ}C$에서는 경유 > 왁스 > 등유 > 가솔린 순이었고, 475$^{\circ}C$와 50$0^{\circ}C$에서는 왁스 > 경유 > 등유 > 가솔린 순이었다.

고장력강의 부식피로에 미치는 용액온도의 영향에 관한 연구 (Study on effect of solution temperature on corrosion fatigue of high strength steel)

  • 유헌일
    • 오토저널
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    • 제8권1호
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    • pp.40-51
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    • 1986
  • A study has been made of the corrosion fatigue of high strength low alloy steel in 3.5% NaCl solution under tension stress for solution temperature being 25.deg. C, 55.deg. C and 85 .deg. C. The main results obtained are as follows; 1) The corrosion fatigue crack growth rate curve could be divided into the First Region, the Second Region and the Third Region. 2) The corrosion fatigue crack growth rates in the First Region and the Second Region were Arrhenius temperature-dependent in this test range. The apparent activation energies for the corrosion fatigue cack growth rate were found to be 2000cal/mol in the First Region and 3700 cal/mol in the Second Region. 3) Hematite (Fe$_{2}$O$_{3}$) as the hexahedral crystal and magnetite (Fe$_{3}$O$_{4}$) as the octahedral crystal were observed in the corrosion products on the corrosion fatigue fracture surface at 85.deg. C and the anode fusion seem to be generated in the crack tip region at high temperature. 4) The complex environment effect ratio which was defined by the ratio of fatigue crack growth rate in corrosion environment to that in air might be considered not only a criterion estimating the effect of environment quantitatively but also an important parameter in the selection of the design stress for the fail safe design. The complex environment effect was not greater than ten in this test.

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Osteoclast Activity and Osteoporosis

  • Kim, Hong-Hee
    • 한국응용약물학회:학술대회논문집
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    • 한국응용약물학회 2001년도 춘계학술대회
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    • pp.103-112
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    • 2001
  • Bone homeostasis is maintained by a balance between activities of osteoblasts(bone forming cells) and osteoclasts (bone resorbing cells). The activities of these cells are closely regulated by multiple factors including hormones and cytokines. The cessation of estrogen at menopause disrupts the balanced regulation and is the main cause of osteoporosis in postmenopausal women. Recent molecular biological studies led to a discovery of tumor necrosis factor(TNF) and TNF receptor families genes that play critical roles in the regulation of osteoclast formation and function. RANKL (receptor activator of nuclear factor kappa B ligand; also called ODF, TRANCE, and OPGL) expressed on cells supporting osteoclast is essential for osteoclast differentiation, activation, and survival. RANK, the counter-receptor for RANKL, is expressed on progenitor and mature osteoclasts. The interaction between RANKL and RANK is requlated by a soluble decoy receptor OPG (osteoprotegerin). Gene knock out studies of these molecules showed profound effects on bone. These results prompted development of new strategies for treatment of bone diseases. Inhibition of osteoclast activity by blocking the RANKL-RANK interaction using OPG is being attempted. Research on the signaling pathways of RANK is also actively carried out. Screening natural products that inhibit the RANKL-RANK interaction or the activity of obteoclasts would be another effective means to a new drug target for bone resorbing diseases.

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