• Korean Journal of Microbiology
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• v.10 no.1
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• pp.29-34
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• 1972

The present study is of ultra-fine structure of Cryptococcus neoformans by means of electron microscopy and reveals the following : 1) In constrast to the bacteria, the normal Cryptococcus neofrmans contains nuclear enveloped with nuclear menbrane, mitochondria, endoplasmic reticulum, distinct cell wall and cell membrane, vacuoles and storage granules as observed in the eucaryotic cells. 2) In apparent cell walls and cell membrane with the appearance of electron transparent area (ETA) and changes of cell morphology were observed in the ultra-violet ray irradiated cell. 2) In apparent cell walls and cell membrance with the appreance of electron transparent area (ETA) and changes of cell morphology were observed in the ultra-violet ray irradiated cell. 3) Morphology changes and cytoplasmic element abnormality was increased with irradiated time. 4) Increase of electron transparent area was thought to be associated with degradation of cell.

• Journal of Embryo Transfer
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• v.13 no.2
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• pp.159-172
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• 1998

사람 성장호르몬 수용체(hGHR) cDNA는 PCR방법에 의하여 fagment로서 보고되어진 바 있으나, liver cDNA로 부터 전장을 cloning한 보고는 없는 실정으로 본 연구에서는 기능을 가진 약 4.6kbp의 cDNA hGHR을 cloning 하는데 성공하였다. 먼저 cloning하기 위하여 human liver mRNA와 human breast cancer tissue로부터 회수한 mRNA를 RT-PCR방법에 의하여 human cDNA library와 cloning에 필요한 probe를 제작하였다. human library mRNA는 GT-PCR방법에 의하여 증폭하여 증폭되어진 산물은 λZAP Vector를 이용하여 cDNA library를 구축하였고,screeing을 위하여 임 보고 되어진 hGHR fragment native sequence를 기초로 N-terminal부분의 primer를 설계하여 950bp의 probe를 얻는데 성공하였다. 이 probe를 이용하여 준비된 human liver cDNA library로부터 2.5$\times$10 6개의 plaque로부터 6개의 positive clone을 획득하였고, 이들중 poly Asignal인 "AATAAA"를 포함하고 있는 가장 긴 약 3.8kbp의 clone을 sequencing한 결과 open reading frame을 포함하고 있었으나, 5'부분의 결손되어 있었다. 그리하여 이 부분은 human breast cancer tissue로 부터 회수한 mRNA를 RT-PCR에 의하여 증폭하였고, sequencing결과 이미 보고되어진 native hGHR와 비교한 결과 하나의 nucleotide가 silent mutation으로 판명되었다.한편 human liver cDNA library로부터 cloning한 3.8cp의 positive clone의 5'end의 결손된 부분에 silent mutation된 PCR 산물을 연결함으로써 native hGHR와 유사한 cDNA hGHR subcloning에 성공하였다. 이러한 cDNA hGHR의 clone이 function을 가지고 있는지를 검토하기 위하여 eukaryotic 발현 vector인 pCXN2에 의거 ligation한 후 chinese hamster ovary cell[CHO-KI]에 transfect를 실시하였다. Dexamethasone은 첨가하지 않고 hGH만의 존재하에서 이들 cell을 배양시키고 cell menbrane에서 발현 여부를 판정키 위하여 hGHR monocloual antibody를 사용하여 flow cytometery해석을 실시하는 한편 125I-hGH binding assay에 의하여 hGH binding activity를 측정하였다. 최종적으로 GH signal transduction의 target genedf으로 알려져 있는 serine protease inhibitor 2.1(Spi 2.1) gene의 promotor activity를 검토한 결과 hGHR을 transfect한 CHO Cell에 있어서 hGH의 농도에 의존적으로 증가되었다. 따라서 본 실험에서 cloning한 cDNA hGHR는 native hGHR와 같은 기능을 가지는 것으로 판명되었다.것으로 판명되었다.

• Journal of the Korea Organic Resources Recycling Association
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• v.21 no.3
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• pp.82-92
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• 2013

The Intermittent Aeration MBR systems have the advantage of controlling reaction time by changing aeration period and are one of economic BNR systems since these processes do not require MLSS recirculation that demands capital and operation costs. In this study, two intermittent aeration MBR systems were studied by computer simulation: an intermittent aeration MBR system that had both 1hr/1hr and 4hr/4hr aeration/unaeration periods at intermittent reactor and NEW INTERMITTENT-process that was an energy saving process and certified as a new process by Korean government. Since DO concentration reached only at 0.23mg/L at intermittent reactor when it was aerated, the Intermittent aeration MBR system having 1hr/1hr aeration/unaeration period showed simultaneous nitrification/denitrification and had the highest nitrogen and phosphorus removal efficiencies that were 57% and 55%, respectively. Since this study was based on the constant influent flow and characteristics, more studies are needed to define the operational characteristics of intermittent aeration MBR systems under dynamic influent conditions.

• 한국생물공학회:학술대회논문집
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• 2000.11a
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• pp.256-259
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• 2000

Ethanol fermentration of glucose by a strain of Zymomonas mobilis KCTC 1535 was studied in membrane recycle bioreactor, which was coupled with closs flow hollow fiber membrane. The maximum values of product yields and productivity are 0.4685g total ethanol/ g glucose, 14.05g total ethanol/ L/h, respectively The pervaporation performance of the PDMS menbrane has been investigated for the separation of binary mixtures of EtOH/water at $50^{\circ}C{\sim}70^{\circ}C$. The optimum conditions of feed concentration, temperature, feed solution flow rates is determined to be 8%, $70^{\circ}C$, 492ml/min, respectively. An ethanol permselectivity of 7.5 and flux of $0.04kg/m^2/hr$ were obtained with these membrane

• Journal of Acupuncture Research
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• v.18 no.1
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• pp.100-112
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• 2001

Objective : The purpose of this study is to investigate the immunological effect of Ramulus Cinnamomum aqua-acupuncture on the cellular immune response in mice with LPS induced arthritis. Methods : All the BALB/C mice used in this study were bred and maintaned in our pathogen-free mouse colony and were 6wk of age at the start of the experiment. The experimental model of arthritis was induced by injeciton of 300${\mu}g$/kg LPS in mice knee joint. Ramulus Cinnamomum aqua-acupuncture was injected into Yangnungchon(Gb34) of mice 2daily for 14days. Immunohistochemical analysis was carried out to assess CD4+, CD8+, CD11b, IL-$1{\beta}$, IL-2R and CD106 expression in common iliac lymph nodes and synovial menbrane after stimulation with Ramulus Cinnamomum. Electron microscopy was carried out to assess change of synovial membrane. Ramulus Cinnamomum aqua-acupuncture stimulation group was compared to control group and non stimutated with aqua-acupuncture. Resutts : At day 14 post arthritis onset, Immunohistological studies using monoclonal antibodies showed that Ramulus Cinnamomum aqua-acupuncture goup had decreased expression of CD4+, CD8+, CD11b, IL-$1{\beta}$, IL-2R and CD106 at common illiac lymph nodes and synovial membrane compared with control group. Conclusions : Ramulus Cinnamomum aqua-acupuncture stimulation inhibited the development of cellular immunity to LPS-induced arthritis in mice. Thus, aqua-acupuncture stimulation may have preventive effects on autoimmune inflammatory joint diseases. The effects of AA on immune function and disease activity in patients with RA warrant further investigation.

• Journal of Food Hygiene and Safety
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• v.7 no.1
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• pp.15-22
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• 1992

This study was conducted to determine the potential of grapefruit seed extract to support Aspergillus parasilicus growth and aflatoxin production. The grapefruit seed extract inhibited the growth and aflatoxin production of the fungi in the level of more than 4,000 ppm and 3,000 ppm in the medium, respectively. Grapefruit seed extract appears to block the conversion of acetate, averufin and versiconal acetate into aflatoxin in vitro experiments. The addition of grapefruit seed extract to the feeding experiment systems did not inhibit the incorporation of 14C-labeled versicolorin A, versicolorin A hemiacetal and sterigmatocystin into aflatoxin. In the electron microscopic examination the biocidal action of grapefruit seed extract was related to the disturbance of cell menbrane funtion, inhibiting cellular respiration.

• Applied Microscopy
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• v.32 no.2
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• pp.121-129
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• 2002

The structure of integumentary epidermis is studied in the bastard halibut, Paralichthys olivaceus based on the light and transmission electron microscope. Epidermal layer consists of supporting cells, unicellular glands and accessory cells. The supporting cells were classified into superficial cell, intermediated cell and basal cell. Superficial cell of epidermal layer is squamous or cuboidal and the surface is covered with numerous microridges. The supporting cells are connected to another cell with membrane interdigitations and desmosmes. And tonofilaments are developed in the cortical cytoplasm. Gland cells are classified into mucous cell and club cell. By the histochemical studies of the epidermal secretions the mucous materials are identified as neutral polysaccharides. Club cell has numerous vacuoles and microfilaments in the cytoplasm. Also chloride cells are observed in the epidermis, it cytoplasm is occupied numerous mitochondria.

• Korean Journal of Microbiology
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• v.22 no.4
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• pp.207-214
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• 1984

Improved methods for the isolation and purification of conidial protoplast were investigated and conidial proplast from auxotrophic mutants were fused. The reaction time for isolation of protoplasts from the swollen condiospores preincubated in liquid minimal medium supplimented with 2-deoxy-D-glucose was shorten by reaction with mixture of 2% driselase and 2% ${\beta}-glucuronidase$ (1:1). The conidial protoplast could be highly purified by using 5% Ficoll 400 as a centrifugation medium. Nucleus of the conidial protoplast was stained with Giemsa stain and the conidial protoplast had one nucleus. It was also confirmed that the conidial protoplast was true protoplast with no cell wall remnant at the outside of plasma menbrane. Fusion frequencies of the conidial protoplast from auxotrophic mutants ranged from $3.4{\times}10^{-1}\;to\;4.9{\times}10^{-1}$. These values were higher than those of mycelial protoplast by a factor of 5 to 28.

• Tuberculosis and Respiratory Diseases
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• v.39 no.4
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• pp.310-317
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• 1992

Background: Angiotensin converting enzyme is a glycoprotein peptidyldipeptide hydrolase which cleaves the c-terminal dipeptides of several oligopeptides. It is a menbrane-bound protein mainly synthesized by the endothelial cells. Since the lung has the largest capillary bed of any organ in the body, it is here that ACE acts on circulating substrates like angiotensin I and bradykinin. It is well known that ACE correlates with disease activity in sarcoidosis and also there are reports that changes in serum ACE activity are found in many acute and chronic lung diseases. So we planned this study to see if serum ACE activity can act as a prognostic factor in lung cancer. Methods: Forty-one newly diagnosed lung cancer patients were included in the study group. There were 19 patients with squamous cell lung cancer, 13 with adenocarcinoma, and 9 with small cell carcinoma. Patients were excluded from the study if they had high blood pressure, heart disease, liver disease, renal disease, or other lung disease. Serum ACE activity was analyzed according to cell type, staging, mode of treatment, and clinical response to treatment. Results: 1) There was no difference in serum ACE activity between lung cancer patients and the control group. Also no difference in serum ACE activity was found according to cancer cell type or staging. 2) In patients who underwent curative resection of lung cancer, serum ACE activity was decreased significantly after the operation. 3) In patients who were diagnosed as non-small cell lung cancer and were treated with 4 cycles of anti-cancer chemotherapy without clinical improvement, changes in serum ACE activity were not seen after the treatment. 4) In patients diagnosed as small cell lung cancer treated with 4 cycles of anti-cancer chemotherapy with clinical improvement, changes in serum ACE activity were also not observed. Conclusion: Serum ACE activity was decreased after lung resection but had no relation to cell type, staging, or clinical response to treatment in lung cancer patients. Therefore, serum ACE activity is not suitable in predicting clinical outcome of lung cancer patients.