• KSBB Journal
• /
• 제15권2호
• /
• pp.174-180
• /
• 2000

본 연구에서는 다른 host cell 에 비하여 여러 가지 장점을 가지고 있는 Methylotrophic yeast 중 Pichia pastoris와 Hans-enula polymorpha의 fed batch 실험을 통하여 유전자 재조합 단백질 발현최적조건을 구하여 각 균주의 유전자 재조합 albumin 발현 최적화 연구를 수행하였다. 글리세롤이 두 균주의 promoter의 AOX 1과 MOX promoter repression에 미치는 영향을 확인한 바 H. polymorpha가 P. pastoris보다 promoter repression이 심함을 알 수 있었다. 두 균주의 promoter를 induction시키는 최적 메탄올 농도는 P. pastoris의 경우 메탄올 8g/L, H. polymorpha의 경우는 13 g/L임을 알 수 있었다. 또한 메탄올에 의한 induction시기는 두 균주 모두 O.D. 4 정도되는 exponential growth stage에서 메탄올을 첨가하는 경우가 초기 세포 성장단계에 메탄올을 첨가한 경우에 비해 약 20% 정도 높아짐을 확인하였다. 두 균주의 재조합 albumin 발현에 미치는 pH의 영향을 조사하였는데, p. pastoris의 경우 pH 5에서 가장 높은 albumin 생산성을 보여 약 300mg/L albumin을 발현하였고, H. polymorpha 의 경우 pH 5와 6에서 최대 약 180 mg/L의 albumin을 발현하였지만 pH 8에서는 이의 절반 수준에 그쳤다. 두 균주의 최적 fed-batch 방법을 확인하는 실험을 수행하였는데 P. pastoris의 경우의 최적 fed-batch 방법은 mixed feeding은 바람직하지 않고 글리세롤 배지를 공급하여 세포를 성장시킨 후 글리세롤 공급을 멈추고 바로 메탄올로 전환하는 방법을 효과적이며, H. polymorpha의 경우 비성장속도 제어를 통한 글리세롤 공급으로부터 메탄올 공급으로의 단계적 전환방법이 균주의 albumin 발현에 큰 영향을 준다는 것을 알 수 있었다. 이 방법을 통하여 두 균주의 고농도 배양 실험을 수행한 결과 P. pastoris의 경우는 O.D. 300에서 약 4.7g albumin/L를 발현하였다. 이와같은 결과를 바탕으로 산업체에서 methlotrophic yeast를 이용한 상업화를 계획함에 있어서 host로서의 균주를 선택할 수 있는 기본 자료를 제공함과 아울러 균주가 선택된 후에 그 균주를 이용한 재조합 단백질 최적화 방법을 제공하여 줄 것으로 생각된다.

• 대한약리학회지
• /
• 제32권1호
• /
• pp.75-82
• /
• 1996

사염화 탄소에 의한 과산화 지질 증가 및 간 손상에 calcium 및 Kupffer cell의 역할 및 calcium channel blocker의 간 손상에 대한 방어 효과를 연구하였다. 사염화 탄소는 (1 gm/kg, ig) 간의 malondialdehyde (nmole/gm liver) 및 혈중 AST와 ALT (lU/ml) 활성도의 현저한 증가를 나타내었다. 고 농도의 Retinol (250,000U/kg/day)로 인한 Kupffer cell의 활성 증가는 사염화 탄소에 의한 간 과산화 지질 증가 및 간 손상에 상승 작용을 나타낸 반면, $GdCl_3$ 전처리는 $CCl_4$로 인한 ALT의 증가를 감소시켰다. 한편 Retinol 처치군에 Diltiazem (10mg/kg/day)을 병행하여 처치한 결과, 사염화 탄소에 의한 혈중 AST 및 ALT의 증가를 Retinol 단독 처치군에 비하여 현저하게 억제시킬 수 있었다. 이 결과들이 Retinol 혹은 Diltiazem의 투여에 의한 사염화 탄소가 cytochrome P450에 의한 대사 활성 또는 GSH와 관련된 항산화 기전에 미치는 영향에 기인한 것인가를 규명하기 위하여 cytochrome P450, cytochrome P4502El 활성도, GSH reductase 및 GSH peroxidase 활성도를 측정하였다. 그 결과, Retinol 및 Diltiazem의 전처리는 이들 효소의 활성도에 미치는 영향은 대조군에 비하여 유의한 차이가 없었다. 이상의 실험 결과를 종합하여 보면, 사염화 탄소의 투여에 의한 간 손상은 세포내 calcium의 증가를 가져오며, 이는 이차적으로 Kupffer cell을 활성화 시켜 이미 손상된 간세포의 독성을 증가시켰으며, calcium channel blocker인 Diltiazem의 투여는 사염화 탄소의 간독성을 현저하게 감소시키는 효과를 나타내었다.

• 한국식품조리과학회지
• /
• 제23권5호
• /
• pp.731-748
• /
• 2007

In this study, we investigated e kinds and names of side dishes along with their recipes and ingredients occuring in Korean cookbooks published before the 17th century. The side dishes were classified 79 kinds of Guk, 23 kinds of Jjim and Seon, 15 kinds of Gui, 3 kinds of Jeon, 7 kinds of Nureumi, 3 kinds of Bokkeum, 30 kinds of Chae, 11 kinds of Hoe, 7 kinds of Jwaban, 6 kinds of Mareunchan, 12 kinds of Pyeonyuk and 5 kinds of Jeonyak, Jokpyeon and Sundae. The earliest records were found on Guk, Jjim, Jwaban, Po and Pyeonyuk Gui, Namul and Hoe were recorded after the 1500's and Nureumi, Jeon, Jeonyak, Jokpyeon and Sundae were developed relatively late in the late 17th century. As to the kinds of side dishes, Guk was the most common. Guks cooked before the 17th century used different recipes and more types of ingredients than today, including some that are not used today. For Jjim, various seasonings were added to main ingredients such as poultry, meat, seafood and vegetable. Most of the records found for Jjim used chicken as the main ingredient. Gui was recorded as Jeok or Gui and there weren't many ingredients for Gui before the 17th century. Gui was usually seasoned with salt or soy bean sauce and broiled after applying oil. Vegetables were broiled after a applying flour-based sauce. The Jeon cooked at that time was different from the one that is cooked today in that cow organs or sparrows were soaked in oily soy bean sauce before being stewed. Nureumi, which was popular in the 17th century, but rarely made today, was a recipe consisting of adding a flour or starch-based sauce to stewed or broiled main ingredients. Chae was a side dish prepared with edible plants, tree sprouts or leaves. Chaes like Donga and Doraji were colored with Mandrami or Muroo. Hoe was a boiled Hoe and served after boiling seafood. Jwaban was cooked by applying oil to and then broiling sparrows, dudeok, and mushrooms that had been seasoned and dried. For dried Chans, beef or fish was thin-sliced, seasoned and dried or sea tangle was broiled with pine nuts juice. There are some recipes from the 17th century whose names are gone or the recipes or ingredients have changed. Thus we must to try to rebuild three recipes and develop recipes using our own foods of today.

• Journal of Acupuncture Research
• /
• 제22권4호
• /
• pp.1-12
• /
• 2005

Objectives : The Purpose of this study is to report in patient with common peroneal nerve palsy, who improved by oriental medical treatament. Methods : We Checked the temperature of a leg by Digital Infrared Thermal Imaging(DITI) at intervals of 10 days, angle of active dorsiflexion and range of active motion for estimating the improvement of symptoms. We used the Visual Analogue Scale(VAS) for estimating the degree of pain, too. Results : After 4 weeks treatment, the movement and power of ankle joint improved to nearly normal range. The degree of active dorsiflexion of the ankle increased from $-40^{\circ}\;to\;15^{\circ}$ and range of active motion increased from Gr III to Gr I. The difference of temperature between the both legs decreased remarkably. Conclusion : In this case we experienced improvement of symptoms by conservative oriental medical therapy, e.g acupuncture stimulation, herbal medication, physical therapy. It should be needed further investigation on common peroneal nerve palsy and its symptoms in order to set up a reasonable standard about a surgical operation.

• 한국식품저장유통학회지
• /
• 제14권3호
• /
• pp.323-327
• /
• 2007

본 연구는 PME 처리가 미생물의 생리변화에 미치는 영향을 중심으로 PME의 항균작용을 규명하기 위해서 소수성 분획과 친수성 분획으로 분리하고, 공시균주를 사용하여 미생물의 성장 및 에너지대사 관련효소의 활성에 미치는 영향을 조사하였다. 매실추출물 분획별 항균활성은 변패미 생물인 C. fragariae를 대상으로 paper disk법으로 관찰하였다. 총 추출물(PME)의 소수성 분획은 C. fragariae의 성장을 저해하기는 하나 그 효과가 총 추출물 보다 약한 반면, 친수성 분획은 총 추출물보다 더 뚜렷한 저해 효과를 보였다. 이와 같은 매실추출물의 분획별 미생물의 생육억제효과는 다른 식품부패미생물 군에서도 동일한 패턴을 보여 주었다. B. cereus, E, coli 및 Fusarium sp.에 대해서는 PME의 친수성 분획은 뚜렷한 항균효과를 보여 주었으며, 총 추출물 또한, 항균력을 나타내었으나, 소수성 분획은 낮은 항균력을 보여 본 실험의 공시균주인 C. fragariae에 대한 매실추출물의 분획별 항균효과를 확인할 수 있었다. 매실 추출물첨가 배지 상에서 C. fragariae의 생육이 크게 억제된다는 실험결과를 토대로 매실추출물의 항균활성물질이 미생물 세포내의 효소계의 효소활성을 저해에 기인한 것인가를 알아보기 위하여, 에너지생성대사에 관여하는 몇 가지 효소 활성(glucose-6-phosphate dehydrogenase, succinate dehydrogenase, malate dehydrogenase, hexokinase)에 미치는 매실추출물의 영향을 살펴보았다. 이 결과로 매실추출물은 총 추출물 및 친수성 분획이 일부 에너지 생성대사 효소계의 효소활성에 영향을 미치는 것으로 나타나(12-40%), 매실 추출물의 항균물질이 세포내로 침투되어 membrane에 존재하는 효소의 활성을 억제하는 것으로 추정할 수 있었다. 본 연구결과를 토대로 미루어, 매실추출물의 항균 작용은 세포내 에너지 생성에 관여하는 효소의 활성을 감소시키는 현상에 기인하는 것으로 추정되었다.

• 한국생명과학회:학술대회논문집
• /
• 한국생명과학회 2001년도 제32회 학술심포지움
• /
• pp.67-86
• /
• 2001

A strain producing strongly fibrinolytic enzyme was isolated from soil and was identified to be Bacillus subtilis by biochemical and physiological characterization. The optimal culture conditions for the production of fibrinolytic enzyme was determined to be 1.0% tryptone, 1.5% soluble starch, 0.5% Peptone, 0.5% NaCl, $(NH_{4})_{3}PO_4.3H_{2}O, and MgSO_{4}.7H_{2}O.$ Initial pH and temperature were pH 8.0 and $30^{\circ}C$ , respectively, The highest enzyme production was observed at 30 hours of cultivation at $30^{\circ}C$ The fibrinolytic enzyme was purified to homogeneity by DEAE Sephadex A-50 ion exchange column chromatography, 70% ammonium sulfate precipitation, Sephadex G-200 and G-75 gel filtration column chromatography. The molecular weight of the purified enzyme was 28,000 as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. A gene encoding the fibrinolytic enzyme was cloned into a plasmid vector pBluescript, transforming E.coli XL-1 Blue. The clone was able to degrade fibrin, This indicated that the gene could encode a fibrinolytic enzyme. The nucleotide sequence of the 2.7 kb insert was determined in both direction. One open reading frame composed of 1023 nucleotides was found to be a potential protein coding region. There was the putative Shine-Dalgano sequence and TATA box upstream of the open reading frame. The homology search data in the genome database showed that both the 2.7 kb insert and 1 kb open reading frame carried no significance in the nucleotide sequence of known fibrinolytic enzyme from Bacillus serovars. The recombinant cell harboring the novel gene involved in fibrinolysis was subjected to protein purification. The molecular mass of the purified fibrinolytic enzyme was determined to be 31864 Dalton, which was highly in accordance with the molecular mass(33 kDa) of the fibrinolytic gene deduced from the insert. The fibrinolytic enzyme was Purified 50.5 folds to homogeneity in overall yield of 10.7% by DEAE Sephadex A-50 ion exchange, 85% ammonium sulfate precipitation, Sephadex G-50, Superdex 75 HR FPLC gel filtration. In conclusion, a novel fibrinolytic gene from Bacillus subtilis was identified and characterized by cloning a genomic library of Bacillus subtilis into pBleuscript. For the soybean fermented by this strain, it is found that there increased assistant protein about 20% compared to the soybean not fermented and increased about 30% according to amino acid analysis and, in particular, essential amino acid increased about 40%. When keeping this fermented soybean powder at room temperature for about 70days, it showed very high stability maintaining almost perfect activity and, therefore, it gave us great suggestion its possibility of development as a new functional food.

• Clinical Psychopharmacology and Neuroscience
• /
• 제16권4호
• /
• pp.398-406
• /
• 2018

Objective: Hospitalization of patients with delirium after visiting the emergency department (ED) is often required. However, the readmission risk after discharge from the ED should also be considered. This study aimed to explore whether (i) immediate hospitalization influences the readmission risk of patients with delirium; (ii) the readmission risk is affected by various risk factors; and (iii) the healthcare cost differs between groups within 28 days of the first ED visit. Methods: Using the National Health Insurance Research Database, the data of 2,780 subjects presenting with delirium at an ED visit from 2000 to 2008 were examined. The readmission risks of the groups of patients (i.e., patients who were and were not admitted within 24 hours of an ED visit) within 28 days were compared, and the effects of the severities of different comorbidities (using Charlson's comorbidity index, CCI), age, gender, diagnosis and differences in medical healthcare cost were analyzed. Results: Patients without immediate hospitalization had a higher risk of readmission within 3, 7, 14, or 28 days of discharge from the ED, especially subjects with more severe comorbidities ($CCI{\geq}3$) or older patients (${\geq}65years$). Subjects with more severe comorbidities or older subjects who were not admitted immediately also incurred a greater healthcare cost for re-hospitalization within the 28-day follow-up period. Conclusion: Patients with delirium with a higher CCI or of a greater age should be carefully considered for immediate hospitalization from ED for further examination in order to reduce the risk of re-hospitalization and cost of healthcare.

• 한국농공학회지
• /
• 제16권1호
• /
• pp.3225-3262
• /
• 1974

The purposes of this thesis are to clarify experimentally the variation of ground water temperature in tube wells during the irrigation period of paddy rice, and the effect of ground water irrigation on the growth, grain yield and yield components of the rice plant, and, furthermore, when and why the plant is most liable to be damaged by ground water, and also to find out the effective ground water irrigation methods. The results obtained in this experiment are as follows; 1. The temperature of ground water in tube wells varies according to the location, year, and the depth of the well. The average temperatures of ground water in a tubewells, 6.3m, 8.0m deep are $14.5^{\circ}C$ and $13.1^{\circ}C$, respercively, during the irrigation period of paddy rice (From the middle of June to the end of September). In the former the temperature rises continuously from $12.3^{\circ}C$ to 16.4$^{\circ}C$ and in the latter from $12.4^{\circ}C$ to $13.8^{\circ}C$ during the same period. These temperatures are approximately the same value as the estimated temperatures. The temperature difference between the ground water and the surface water is approximately $11^{\circ}C$. 2. The results obtained from the analysis of the water quality of the "Seoho" reservoir and that of water from the tube well show that the pH values of the ground water and the surface water are 6.35 and 6.00, respectively, and inorganic components such as N, PO4, Na, Cl, SiO2 and Ca are contained more in the ground water than in the surface water while K, SO4, Fe and Mg are contained less in the ground water. 3. The response of growth, yield and yield components of paddy rice to ground water irrigation are as follows; (l) Using ground water irrigation during the watered rice nursery period(seeding date: 30 April, 1970), the chracteristics of a young rice plant, such as plant height, number of leaves, and number of tillers are inferior to those of young rice plants irrigated with surface water during the same period. (2) In cases where ground water and surface water are supplied separately by the gravity flow method, it is found that ground water irrigation to the rice plant delays the stage at which there is a maximum increase in the number of tillers by 6 days. (3) At the tillering stage of rice plant just after transplanting, the effect of ground water irrigation on the increase in the number of tillers is better, compared with the method of supplying surface water throughout the whole irrigation period. Conversely, the number of tillers is decreased by ground water irrigation at the reproductive stage. Plant height is extremely restrained by ground water irrigation. (4) Heading date is clearly delayed by the ground water irrigation when it is practised during the growth stages or at the reproductive stage only. (5) The heading date of rice plants is slightly delayed by irrigation with the gravity flow method as compared with the standing water method. (6) The response of yield and of yield components of rice to ground water irrigation are as follows: \circled1 When ground water irrigation is practised during the growth stages and the reproductive stage, the culm length of the rice plant is reduced by 11 percent and 8 percent, respectively, when compared with the surface water irrigation used throughout all the growth stages. \circled2 Panicle length is found to be the longest on the test plot in which ground water irrigation is practised at the tillering stage. A similar tendency as that seen in the culm length is observed on other test plots. \circled3 The number of panicles is found to be the least on the plot in which ground water irrigation is practised by the gravity flow method throughout all the growth stages of the rice plant. No significant difference is found between the other plots. \circled4 The number of spikelets per panicle at the various stages of rice growth at which_ surface or ground water is supplied by gravity flow method are as follows; surface water at all growth stages‥‥‥‥‥ 98.5. Ground water at all growth stages‥‥‥‥‥‥62.2 Ground water at the tillering stage‥‥‥‥‥ 82.6. Ground water at the reproductive stage ‥‥‥‥‥ 74.1. \circled5 Ripening percentage is about 70 percent on the test plot in which ground water irrigation is practised during all the growth stages and at the tillering stage only. However, when ground water irrigation is practised, at the reproductive stage, the ripening percentage is reduced to 50 percent. This means that 20 percent reduction in the ripening percentage by using ground water irrigation at the reproductive stage. \circled6 The weight of 1,000 kernels is found to show a similar tendency as in the case of ripening percentage i. e. the ground water irrigation during all the growth stages and at the reproductive stage results in a decreased weight of the 1,000 kernels. \circled7 The yield of brown rice from the various treatments are as follows; Gravity flow; Surface water at all growth stages‥‥‥‥‥‥514kg/10a. Ground water at all growth stages‥‥‥‥‥‥428kg/10a. Ground water at the reproductive stage‥‥‥‥‥‥430kg/10a. Standing water; Surface water at all growh stages‥‥‥‥‥‥556kg/10a. Ground water at all growth stages‥‥‥‥‥‥441kg/10a. Ground water at the reproductive stage‥‥‥‥‥‥450kg/10a. The above figures show that ground water irrigation by the gravity flow and by the standing water method during all the growth stages resulted in an 18 percent and a 21 percent decrease in the yield of brown rice, respectively, when compared with surface water irrigation. Also ground water irrigation by gravity flow and by standing water resulted in respective decreases in yield of 16 percent and 19 percent, compared with the surface irrigation method. 4. Results obtained from the experiments on the improvement of ground water irrigation efficiency to paddy rice are as follows; (1) When the standing water irrigation with surface water is practised, the daily average water temperature in a paddy field is 25.2$^{\circ}C$, but, when the gravity flow method is practised with the same irrigation water, the daily average water temperature is 24.5$^{\circ}C$. This means that the former is 0.7$^{\circ}C$ higher than the latter. On the other hand, when ground water is used, the daily water temperatures in a paddy field are respectively 21.$0^{\circ}C$ and 19.3$^{\circ}C$ by practising standing water and the gravity flow method. It can be seen that the former is approximately 1.$0^{\circ}C$ higher than the latter. (2) When the non-water-logged cultivation is practised, the yield of brown rice is 516.3kg/10a, while the yield of brown rice from ground water irrigation plot throughout the whole irrigation period and surface water irrigation plot are 446.3kg/10a and 556.4kg/10a, respectivelely. This means that there is no significant difference in yields between surface water irrigation practice and non-water-logged cultivation, and also means that non-water-logged cultivation results in a 12.6 percent increase in yield compared with the yield from the ground water irrigation plot. (3) The black and white coloring on the inside surface of the water warming ponds has no substantial effect on the temperature of the water. The average daily water temperatures of the various water warming ponds, having different depths, are expressed as Y=aX+b, while the daily average water temperatures at various depths in a water warming pond are expressed as Y=a(b)x (where Y: the daily average water temperature, a,b: constants depending on the type of water warming pond, X; water depth). As the depth of water warning pond is increased, the diurnal difference of the highest and the lowest water temperature is decreased, and also, the time at which the highest water temperature occurs, is delayed. (4) The degree of warming by using a polyethylene tube, 100m in length and 10cm in diameter, is 4~9$^{\circ}C$. Heat exchange rate of a polyethylene tube is 1.5 times higher than that or a water warming channel. The following equation expresses the water warming mechanism of a polyethylene tube where distance from the tube inlet, time in day and several climatic factors are given: {{{{ theta omega (dwt)= { a}_{0 } (1-e- { x} over { PHI v })+ { 2} atop { SUM from { { n}=1} { { a}_{n } } over { SQRT { 1+ {( n omega PHI) }^{2 } } } } LEFT { sin(n omega t+ { b}_{n }+ { tan}^{-1 }n omega PHI )-e- { x} over { PHI v }sin(n omega LEFT ( t- { x} over {v } RIGHT ) + { b}_{n }+ { tan}^{-1 }n omega PHI ) RIGHT } +e- { x} over { PHI v } theta i}}}}{{{{ { theta }_{$\infty$ }(t)= { { alpha theta }_{a }+ { theta }_{ w'} +(S- { B}_{s } ) { U}_{w } } over { beta } , PHI = { { cpDU}_{ omega } } over {4 beta } }}}} where $\theta$$\omega$; discharged water temperature($^{\circ}C$) $\theta$a; air temperature ($^{\circ}C$) $\theta$$\omega$';ponded water temperature($^{\circ}C$) s ; net solar radiation(ly/min) t ; time(tadian) x; tube length(cm) D; diameter(cm) ao,an,bn;constants determined from $\theta$$\omega$(t) varitation. cp; heat capacity of water(cal/$^{\circ}C$ ㎥) U,Ua; overall heat transfer coefficient(cal/$^{\circ}C$ $\textrm{cm}^2$ min-1) $\omega$;1 velocity of water in a polyethylene tube(cm/min) Bs ; heat exchange rate between water and soil(ly/min)

• 한국토양비료학회지
• /
• 제43권3호
• /
• pp.315-321
• /
• 2010

시설재배는 폐쇄된 환경에서 제한적인 물관리로 인하여 작기 중에는 외부에 영향을 미치지 않으나, 작물 생산 이후 토양 중 집적된 염류를 제거하기 위해 담수처리를 하게 되는데, 이 때 토양 중 염류가 지표유출 및 용탈을 통하여 주변 수질에 영향을 직접 미치고 있어서 이에 대한 정량적인 평가를 하였다. 입지조건이 다른 두 시설재배지인 경북 상주시 서곡동에 위치한 시설하우스에서 2008년 7월 중순부터 9월 중순까지 시험 전 후의 토양 화학성, 관개량 및 관개수질, 침투수량 및 침투수질, 표면수질, 그리고 조사기간 동안 주변 하천 수질을 조사하였다. 하성평탄지에서는 담수직후의 제염률은 60.4%로 곡간지에 비해 훨씬 높았으며 76.6%까지 높아졌다가 담수 20일 후에는 66.7%이었다. 담수초기부터 곡간지의 표면수중 $NH_4$-N과 $PO_4$-P 농도가 하성평탄지보다 높았으며, 곡간지에서 담수직후와 담수종료 후의 토양깊이별 $Cl^-$과 ${SO_4}^{2-}$ 농도는 큰 차이가 있었으나, 하성평탄지에서는 토양깊이별 ${SO_4}^{2-}$ 농도만 차이가 있었다. 침투수중 $NO_3$-N 농도 변화는 곡간지에 비해 하성평탄지에서 변화의 폭이 컸으며, 시간이 경과할수록 그리고 토양이 깊어질수록 그 농도도 높았다. 또한, 곡간지와 하성평탄지에 있는 시설재배지에서 담수제염에 의한 질소와 인수지를 비교 평가해 본 결과 곡간지와 하성평탄지 모두 유입 부하량보다 유출 부하량이 많아 외부 수계의 영향을 주는 것으로 평가되었다. 특히, 곡간지에 비해 하성평탄지에서의 양분 부하량이 더 많은 것으로 평가되었는데, 곡간지에서는 지하용탈만으로 제염을 하여 지하수의 수질에 영향을 주고 하성평탄지에서는 지하용탈뿐만 아니라 지표용탈에 의한 제염으로 인해 하천수의 수질에 영향을 주는 것으로 평가되었다.

• 한국수정란이식학회지
• /
• 제19권2호
• /
• pp.101-112
• /
• 2004

본 연구는 포유류인 $Cl^-$통로의 존재 여부를 확인하기 위하여 수행되었다. $Cl^-$통로는 비흥분성 세포에서 용적변화와 pH 조절, 이온운반계 등에 중요한 역할을 수행하므로 활발한 세포분화가 이루어지는 난자의 생존과 기능에 필수적 $Cl^-$통로 존재 여부를 확인하고자 하였다. 단일통로 전류를 기록하는 patch clamp 기법을 이용하였다. 세포외(pipette) 용액을 140 mM NaCl로 하고 세포내(bath) 용액을 70 mM, 140 mM, 280 mM NaCl로 바꾸어 주었을 때, 역전압($E_{rev}$) 은 $Cl^-$평형전압을 반영하는 -9.8${\pm}$0.5mV, 0mV, 11.5${\pm}$0.2mV로 변화하였다(n=4). 이런 결과는 이론치와 약간의 편차를 보이고 있으므로 이를 보정하기 위항 Goldman-Hodgkin-Katz(GHK) 식을 이용한 결과 $Cl^-$에 대한 $Na^+$의 투과성 ($P_{Na}$/$P_{Cl}$/)은 0.25로 추측할 수 있었다. Inside out patch mode에서 Pipette 용액과 bath 용액에 imperment인 NMDG-Cl로 구성하였을 경우 단일 통로가 기록되었다.(n=22). 막전압이 증가함에 따라 전도도(conductance)가 같이 증가하였으며 전류-전압 관계는 outward rectification을 보였다. 이런 특성을 나타내는 단일통로로 전류는 선택적 $Cl^-$통로 차단제인 IAA-94(indanyloxyacetic acid 94)에 의해 농도 의존적으로 차단되었으며 가역적으로 회복되었다. IAA의 $IC_{50}$은 32.6$\mu\textrm{M}$이었다. DIDS(4,4'-diisothiocyan ostillben-2-2'disulfonic acid)에 의해서는 전류크기가 감소 되는 빠른 억제기전을 나타내는 차단효과를 보였으며 시간경과에 따라 seblevel로 감소되는 subconductance block 이 나타났다. 이상의 결과는 햄스터 난자에서 chloride 통로가 존재하여, 물질이동과 pH 조절기능을 나타내는 외향성 전류-전압관계를 보이는 $Cl^-$ 통로의 성상으로 미루어 볼 때 난자의 pH 조절과 용적조절과 같은 생리적 환경 조성에 관여할 것으로 추정된다.