• 제목/요약/키워드: Alkylating agent

검색결과 61건 처리시간 0.027초

해양 호염성 세균 Vibrio alginolyticus가 생산하는 Extracellular Amylase의 특성 (Properties of an Extracellular Amylase Produced by the Marine Halophilic Bacterium Vibrio alginolyticus)

  • 김영재
    • 한국미생물·생명공학회지
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    • 제27권3호
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    • pp.203-207
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    • 1999
  • V. alginolyticus 138-2, a marine halophilic bacterium, produced an extracellular amylase with a molecular weight of ca. 56,000. The analysis of the digestion products of soluble starch by thin layer chromatography(TLC) revealed that the extracellular amylase of V. alginolyticus 138-2 is a saccharifying-type alpha-amylase. The alpha-amylase activity of the culture supernatant of soluble starch was optimal at pH 6.0 and 45$^{\circ}C$. Ca2+ slightly increased the alpha-amylase activity, whereas Hg2+, An2+, Cu2+, Ni2+, Fe2+, and Mn2+inhibited the enzymatic activity. Alkylating thiol group agent, iodoacetic acid did not affect the alpha-amylase activity, but reduced thiol reagents such as dithiothreitol, cysteine, and beta-mercaptoethanol stimulated theenzymatic activity. On the other hand, even if V. alginolyticus 138-2 is a marine halophilic bacterium, its alpha-amylase activity was significantly inhibited by NaCl.

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$^{32}P$-Postlabelling 방법을 이용한 미토마이신 C에 의하여 형성된 DNA adduct의 검출 (Detection of DNA Adduct Formed by Mitomycin C by $^{32}P$-Postlabelling)

  • 정혜윤;김재현;박창원;이동권
    • 약학회지
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    • 제40권4호
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    • pp.442-448
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    • 1996
  • Mitomycin C(MMC) has been used as an anticancer drug and behaves as an alkylating agent forming covalent cross-link between complementary strands of double strand DNA. The purpose of this research was to determine number of DNA adducts, formed in vivo by Mitomycin C, in mouse organs. DNAs from liver, lung, brain and pancreas were isolated and used for $^{32}P$-postlabelling. The labeled nucleotides were separated by 2D-TLC and subjected to autoradiography. Numbers of MMC-DNA adducts were 9,9,5,4 in liver, pancreas, lung and brain, respectively.

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Immunomodulatory Activity of the Water Extract from Medicinal Mushroom Inonotus obliquus

  • Kim, Yeon-Ran
    • Mycobiology
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    • 제33권3호
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    • pp.158-162
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    • 2005
  • The immunomodulatory effect of aqueous extract of Inonotus obliquus, called as Chaga, was tested on bone marrow cells from chemically immunosuppressed mice. The Chaga water extract was daily administered for 24 days to mice that had been treated with cyclophosphamide (400 mg/kg body weight), immunosuppressive alkylating agent. The number of colony-forming unit (CFU)-granulocytes/macrophages (GM) and erythroid burst-forming unit (BFU-E), increased almost to the levels seen in non-treated control as early as 8 days after treatment. Oral administration of the extract highly increased serum levels of IL-6. Also, the level of $TNF-{\alpha}$ was elevated by the chemical treatment in control mice, whereas was maintained at the background level in the extract-treated mice, indicating that the extract might effectively suppress $TNF-{\alpha}$ related pathologic conditions. These results strongly suggest the great potential of the aqueous extract from Inonotus obliquus as immune enhancer during chemotherapy.

반응성을 이용한 항암성 2-alkoxy-1-arylsufonylimidazoline 유도체의 설계 및 합성

  • 정상헌;송재신
    • 한국응용약물학회:학술대회논문집
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    • 한국응용약물학회 1992년도 제1회 신약개발 연구발표회 초록집
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    • pp.16-16
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    • 1992
  • 1940년대에 처음으로 암의 화학요법이 시도된 이래 많은 항암제들이 도입되어 사용되고 있다. 현재 항암제를 사용하여 비교적 치료율이 높은 암은 leukemia나 lymphoma와 같은 혈액암에 국한되어 있다. 고형암에 대하여는 고환암과 같은 극히 일부가 항암제에 의해 비교적 잘 치료되나 대부분은 여전히 치료가 되지 않고 있는 상태에 있다. 고형암의 발생빈도는 전체 암의 90%를 차지하고 있는 상태로 사망율이 매우 높아, 현대의 40대 이상 사망원인의 1위를 나타내고 있어 그 치료제의 개발이 매우 시급히 요구되고 있다. 이에 따라 고형암의 치료를 목적으로 많은 화합물들이 검토되어 왔다. 이중 최근 매우 큰 가능성을 보여주고 있는 diarysulfonylurea 유도체가 발견되어 임상시험에 도입됨으로서 이 화합물들에 대한 관심이 고조되고 있다. 이와 관련하여 고형암의 치료제를 개발할 목적으로 diarysulfonylurea의 특성과 강력한 항암효과를 발현하는 alkylating agent의 특성을 갖을 것으로 예상되는 새로운 2-alkoxy-1-arylsufonylimidazoline 유도체를 설계하고, 이들 유도체의 합성법을 개발하였다. 이들 유도체들은 일차적으로 생체내에서 DNA 또는 효소등에 alkylation을 일으킨후 diarysulfonylurea로 변하여 작용함으로서 보다 큰 항암효과를 발현할 것으로 기대된다.

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isopropyl acetate을 이용한 페놀의 isopropylation 반응의 Al-MCM-48 분자체 촉매반응 특성 (Catalytic performance of Al-MCM-48 molecular sieves in the isopropylation of phenol with isopropyl acetate)

  • 칸단 벤카타찰람;푸시파라지 헤마라다;팽메이메이;장현태
    • 한국산학기술학회:학술대회논문집
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    • 한국산학기술학회 2011년도 춘계학술논문집 1부
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    • pp.144-146
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    • 2011
  • Al-MCM-48 molecular sieves (Si/Al = 25, 50, 75 and 100) were synthesized hydrothermally using cetyltrimethyl ammonium bromide as the structure directing template. The orderly arrangement of mesopores was evident from the low angle X-ray diffraction patterns and TEM images. The catalytic performance was evaluated in the vapour phase isopropylation of phenol with isopropyl acetate. Phenol conversion decreased with increase in the Si/Al ratio of the catalysts. The major reaction product was 4-isopropyl phenol (selectivity: 78%). Delocalization of phenolic oxygen electron pair over the aromatic ring promoted para-selective alkylation. Such delocalization could be aided by the hydrophilic surface of the molecular sieves. Though ester was used as the alkylating agent, phenyl isopropyl ether was not formed

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Generation and Evaluation of High ${\beta}$-Glucan Producing Mutant Strains of Sparassis crispa

  • Kim, Seung-Rak;Kang, Hyeon-Woo;Ro, Hyeon-Su
    • Mycobiology
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    • 제41권3호
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    • pp.159-163
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    • 2013
  • A chemical mutagenesis technique was employed for development of mutant strains of Sparassis crispa targeting the shortened cultivation time and the high ${\beta}$-glucan content. The homogenized mycelial fragments of S. crispa IUM4010 strain were treated with 0.2 vol% methyl methanesulfonate, an alkylating agent, yielding 199 mutant strains. Subsequent screening in terms of growth and ${\beta}$-glucan content yielded two mutant strains, B4 and S7. Both mutants exhibited a significant increase in ${\beta}$-glucan productivity by producing 0.254 and 0.236 mg soluble ${\beta}$-glucan/mg dry cell weight for the B4 and S7 strains, respectively, whereas the wild type strain produced 0.102 mg soluble ${\beta}$-glucan/mg dry cell weight. The results demonstrate the usefulness of chemical mutagenesis for generation of mutant mushroom strains.

Protective effects of Ginsan against Cyclophosphamide-induced immunosuppression in mice

  • Shim, Ji-Young;Ahn, Ji-Yeon;Han, Young-Soo;Jung, In-Sung;Yun, Yeon-Sook;Song, Jie-Young
    • 대한약학회:학술대회논문집
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    • 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.1
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    • pp.206.1-206.1
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    • 2003
  • The immunomodulator Ginsan has been found previously by us to stimulate the secretion of high levels of IL -1. IL -6 and TNF-alpha in irradiated mice. These cytokines are known to induce proliferation and differentiation of hematopoietic progenitor cells from the spleen and bone marrow and to protect mice from DNA-damaging agents. The present studies were evaluated as a cytoprotective agent against toxicity of the alkylating drugs. (omitted)

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Modulation of Corydalis tuber on Glycine-induced Ion Current in Acutely Dissociated Rat Periaqueductal Gray Neuron

  • Cheong, Byung-Shik;Nam, Sang-Soo;Choi, Do-Young
    • 대한한의학회지
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    • 제24권4호
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    • pp.34-42
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    • 2003
  • This study was designed to investigate the modulation of the Corydalis tuber on glycine-activated ion current in rat periaqueductal gray (PAG) neurons. Aqueous extract from Corydalis tuber has been widely used for pain control such as dysmenorrhea, irregular menstruation or amenorrhea with abdominal cramping, neuralgia, headache and gastrointestinal spasm. The PAG region of the brain is known to be involved heavily with nociception. Modulation of the Corydalis tuber on glycine-induced ion current in rat periaqueductal gray (PAG) neurons was studied by a nystatin-perforated patch-clamp technique. High concentrations of Corydalis tuber elicited ion current, which was suppressed by strychnine application. Low concentrations of Corydalis tuber reduced glycine-induced ion currents in the PAG neurons. Inhibitory action of Corydalis tuber on glycine-activated ion current was reduced by treatment with naltrexone, a non- selective opioid antagonist. Application of N-methylmalemide (NEM), a sulfhydryl alkylating agent, also reduced the inhibitory action of Corydalis tuber on glycine-activated ion current in the PAG neurons. These results suggest that the inhibitory effect of Corydalis tuber on glycine-activated ion current in the PAG neurons is one of the analgesic mechanisms of the Corydalis tuber, which may activate descending pain control system in PAG neurons.

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하악골에 발생한 다발성골수종의 증례보고 (MULTIPLE MYELOMA OF MANDIBLE : REPORT OF A CASE)

  • 장현석;이기철
    • Maxillofacial Plastic and Reconstructive Surgery
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    • 제18권4호
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    • pp.706-711
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    • 1996
  • 다발성 골수증은 다양한 증세를 보이는 형질세포로부터 기원하는 악성종양으로 40세이상의 남성에서 호발되며 alkylating agent 단독, 혹은 corticosteroid와 병용하는 항암제 치료로 생존율이 크게 증가되기는 하였지만 치료후 평균생존기간의 20개월 내외로 완치율이 그다지 높지않은 형편이다. 악골에서의 발생은 극히 드물고 대개 늑골, 편평골, 척추, 골반, 두개골등에 광범위한 patchy destruction의 형태로 나타나는데 악골에 발생할 경우 임상증상은 장기적인 무통성 종창이 가장 흔하며 때로는 동통, 악골의 팽창, 감각이상, 치아의 동요, 악골골절등을 보이기도 한다. 전신적증상으로 무력감, 체중감소, 빈혈, 신부전, hypercalcemia, hyperiviscosity syndrome을 나타내기도 하는데 약 10%의 환자에서 전신적인 amyloidosis를 보인다. 진단은 골수생검상 골수의 plasmacytosis가 10% 이상이면서 혈장이나 뇨전기영동법에서 monoclonal globulin peak이 있을 때 가능하다. 여러 학자들은 처음에는 독립적인 고립성병소로 나타났다가 장기적으로 다발성골수종으로 이행됨을 주장하면서 장기적인 추적을 권하고 있지만 골내 고립성 형질세포종(solitary plasmacytoma in bone), 수질외 형질세포종(extramedullary plasmacytoma) 등은 다발성골수종과는 다른 질환이라 주장하는 등 아직 많은 논란이 있는 형편이다. 치료는 $4000{\sim}6000$ rad의 방사선치료와 여러 가지 약제의 복합적인 항암요법이 사용되고 있으며 국소적인 병소의 경우 외과적 절제술이 추천되기도 한다. 저자들은 59세 여자환자에서 하악골에 발생된 다발성골수종을 치험하였기에 문헌고찰과 함께 보고하는 바이다.

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