(An) experimental study on nucleic acid in skin carcinogenesis process of DMBA painted white rats

치의학과/석사[한글]DMBA와 같은 Polycyclic hydrocarbon들은 생체내에서 핵산이나 단백질과 같은 거대분자와 결합을 하여 DNA나 RNA의 생합성을 억제한다. 또한 이들 polycyclic hydrocarbon은 in vitro에서도 DNA 생합성을 억제하며 피부이외의 다른 조직에서도 DNA 생합성을 억제한다. Frei등은 피부에 DMBA를 도포시 처음 초기에 DNA생합성이 억제된 후 곧 3∼4배 증가된다고 보고하였다. Slage등은 alkylating agent가 처음에는 DNA생합성을 억제하나 곧 증진시켰다고 보고하였다. 그러나 현재까지는 발암과정의 초기, 즉 initiation단계에서의 DNA나 RNA 생합성에 관한 연구는 많았으나 promotion단계 이후에서부터 암이 발생된 후까지의 DNA나 RNA생합성 능력에 대한 연구가 드물어 이에 저자는 암 발생 전 과정의 핵산생합성 능력에 대한 기초 자료를 얻고자 DMBA도포에 의한 백서의 피부암 발암과정에서 암 발생 후까지의 조직을 절제하여 DNA와 RNA의 양을 정량하여 다음과 같은 결론을 얻었다. 1. 기간에 따른 조직 9당 DNA양의 변화는 9주까지는 대조군과 실험군이 큰 차이가 없었으나 육안적으로 종양이 관찰되기 시작하는 11주째와 13주에서는 대조군에 비해 실험군이 1.65 ± O.51mg / g에서 3.01 ± 0.32mg / g으로, 1.59 ± 0.61mg / g에서 2.95 ± 0.32 mg / g으로 현저히 증가되었다. 그러나 15주 이후에서는 대조군과 실험군이 큰 차이가 나타나지 않았다. 단백질 mg당 DNA양의 변화도 9주까지는 대조군과 실험군이 큰 차이가 없었으나 육안적으로 종양이 관찰되기 시작하는 11주째는 대조군에 비해 2.61 ± 0.38mg / mg에서 3.95 ± 0.82mg / mg으로 급격히 증가하였으며 13주 이후에도 계속적인 증가상을 보였다. 2. 기간에 따른 조직g당 RNA양의 변화는 DNA에서와 같이 9주째까지는 대조군과 실험군이 큰 차이가 없었으며 육안적으로 종양이 관찰되기 시작하는 11주째와 13주에서 대조군에 비해 실험군이 1.63 ± 0.45mg / g에서 2.58 ± 0.36mg / g으로, 1.71 ± 0.73mg / g 에서 2.60 ± 0.45mg / g으로 현저히 증가되었으며 15주 이후에서도 대조군과 실험군이 큰 차이가 나타나지 않았다. 단백질 mg당 RNA 양의 변화는 9주째까지는 대조군과 실험군이 큰 차이가 없었으나 육안적으로 종양이 관찰되기 시작하는 11주째부터 대조군에 비해 실험군이 2.51 ± 0.58mg / mg에서 3.35 ± 0.53 mg / mg으로, 13주째는 2.61 ± 0.73mg / mg에서 3.51 ± 0.52mg / mg으로, 15주째는 2.38 ± 0.52mg / mg에서 6.51 ± 0.93 mg / mg으로 계속적으로 증가하다가 17주부터는 감소하기 시작했다. 이상의 결과로 보아 DMBA에 의한 피부암 발생시 육안적으로 종양이 관찰되기 시작하는 11주째에 핵산의 양이 현저히 증가되어 종양세포의 세포분열에 필요한 DNA, RNA를 공급하게되며 진행과정에서도 계속적인 세포분열에 영향을 준 것으로 생각된다. [영문]The purpose of this study was to investigate ability of nucleic acid synthesis in carcinogenesis process. About 80g weighed male White Rats were used in this experimental study, and divided into control and experimental groups. The experimental groups were painted with 0.5% DMBA in mineral oil and the control groups were painted with mineral oil only on the back skin surface two times weekly. The animals were sacrificed at every 1, 3, 5, 7, 9, 11, 13, 15, 17, 19th week and excised the painted area for extraction of nucleic acid. The obtained results were as follows; 1. In carcinogenesis process, changes of DNA amount per g tissue were not remarkable until 9th week, but markedly increased in experimental group at 11th and 13th week. However, there were not much differences after 15th week. Changes of DNA amount per mg protein were not remarkable until 9th week, but it has markedly increased in experimental group after 11th week and continuously increased. 2. In carcinogenesis process, changes of RNA amount per g tissue were not remarkable until 9th week, but markedly increased in experimental group at 11th and 13th week. However, there were not much differences after 15th week. Changes of RNA amount per mg protein were not remarkable until 9th week, but marked increased in experimental group from 11th to 15th week. However, RNA amount per mg protein were decreased after 17th week. From the above, as skin carcinogenesis induced by DMBA, the author suggest that nucleic acid were markedly increased from the detection of tumor by visual inspection and it might be supplied to DNA, RNA for tumor cell divisions. And during tumor progression, nucleic acid were continuously increased and influenced to tumor cell divisions.restrictio

적합성 시험에서 시험데이타 값 결정방법 연구

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Molecular cloning and characterization of a major egg antigen in Paragonimus westermani and its use in ELISA for the immunodiagnosis of paragonimiasis

A recombinant protein of a Paragonimus westermani egg antigen was produced and tested as an antigen for the serologic diagnosis of P. westermani infection. The P. westermani egg antigen gene contains a single open reading frame of 966 base pairs encoding 322 amino acids from 5′ methionine to the 3′ stop codon. The predicted amino acid sequence of this egg antigen was 40, 38, and was 35% identical to heat shock proteins from Schistosoma japonicum, Schistosoma mansoni, and Taenia saginata. The distribution this antigen was investigated in adult worms by indirect immunofluorescence assay, and found to be distributed in eggs and uteri. The specificity and sensitivity of the recombinant antigen were assessed by enzyme-linked immunosorbent assay (ELISA) using sera from patients infected with different parasites, which included 41 patients with paragonimiasis, and negative controls. The diagnostic positive and negative predictive absorbance value was 0.24 and the sensitivity of ELISA using the recombinant antigen was 90.2%, and its specificity 100%. Our results suggest that the developed recombinant major egg antigen-based ELISA offers a highly sensitive and specific assay for the diagnosis of paragonimiasis.ope

Molecular cloning and the allergenic characterization of tropomyosin from Tyrophagus putrescentiae

Storage mites have been recognized as a cause of asthma and rhinitis. Studies from several countries have shown that the IgE-mediated allergy to storage mites is of considerable importance, especially in rural populations. This study aimed to identify and characterize new allergens from Tyrophagus putrescentiae. A partial cDNA sequence encoding tropomyosin was isolated from the cDNA library by immunoscreening using anti-mouse IgG1 sera raised against T. putrescentiae whole body extract. The deduced amino acid sequence shares 64-94% identity with previously known allergenic tropomyosins. Its recombinant protein was produced by using a pET 28b expression system and purified by affinity chromatography using Ni-NTA agarose. The IgE reactivities of tropomyosins from T. putrescentiae and Dermatophagoides farinae were compared by enzyme linked immunosorbent assay (ELISA). Recombinant Tyr p 10 showed 12.5% (5/40) IgE-binding reactivity, whereas recombinant Der f 10 showed 25% (10/40) IgE-binding reactivity against the same sera from storage mite-sensitized and house dust mite-sensitized subjects. Both recombinant Tyr p 10 and Der f 10 showed little inhibition of IgE binding to T. putrescentiae crude extract by ELISA. Tropomyosin seems to contribute only a small portion of the cross-reactivity with house dust mites.ope