• 한국균학회소식:학술대회논문집
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• 한국균학회 2014년도 추계학술대회 및 정기총회
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• pp.13-13
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• 2014

Species belonging to the genus Fusarium are widely distributed and cause diseases in many plants. Isolation of fungal strains from air or cereals is necessary for disease forecasting, disease diagnosis, and population genetics [1]. Previously we showed that Fusarium species are resistant to toxoflavin produced by the bacterial rice pathogen Burkholderia glumae while other fungal genera are sensitive to the toxin, resulting in the development of a selective medium for Fusarium species using toxoflavin [2]. In this study, we have tried to elucidate the resistant mechanism of F. graminearum against toxoflavin and interaction between the two pathogens in nature. To test whether B. glumae affects the development of F. graminearum, the wild-type F. graminearum strains were incubated with either the bacterial strain or supernatant of the bacterial culture. Both conditions increased the conidial production five times more than when the fungus was incubated alone. While co-incubation resulted in dramatic increase of conidial production, conidia germination delayed by either the bacterial strain or supernatant. These results suggest that certain factors produced by B. glumae induce conidial production and delay conidial germination in F. graminearum. To identify genes related to toxoflavin resistance in F. graminearum, we screened the transcriptional factor mutant library previously generated in F. graminearum [3] and identified one mutant that is sensitive to toxoflavin. We analyzed transcriptomes of the wild-type strain and the mutant strain under either absence or presence of toxoflavin through RNAseq. Expression level of total genes of 13,820 was measured by reads per kilobase per million mapped reads (RPKM). Under the criteria with more than two-fold changes, 1,440 genes were upregulated and 1,267 genes were down-regulated in wild-type strain than mutant strain in response to toxoflavin treatment. A comparison of gene expression profiling between the wild type and mutant through gene ontology analysis showed that genes related to metabolic process and oxidation-reduction process were highly enriched in the mutant strain. The data analyses will focus on elucidating the resistance mechanism of F. graminearum against toxoflavin and the interaction between the two pathogens in rice. Further evolutionary history will be traced through figuring out the gene function in populations and in other filamentous fungi.

• 대한한의학회지
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• 제23권1호
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• pp.120-132
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• 2002

Objectives : The purpose of this investigation was to evaluate the effect of Goomicheongsim-won Extracts on E20 corticells and P7 cerebellar cells exposed to hypoxia, and the effect on neuronal protection by elimination of Rhinoceros unicornis L. and/or Orpiment $As_2S_3$. Methods : P7 cerebellar cells were grown in various concentrations of KM-A, KM-B, KM- C and KM-D. On 7 DIV (day in vitro), cells were exposed to hypoxia (98% $N_2/5%{;}CO_2,{\;}3{\;}hr,{\;}37^{\circ}C$) and normoxia, and then further incubated for 3 days. Neuronal viabilities were expressed as percentages of control. E20 cortical cells were grown in various concentrations of KM-A, KM-B, KM-C, and KM-D. On 7 DIV, cells were exposed to hypoxia and normoxia, and then further incubated for 3 and 7 days. Results : I. The effect of KM-A on neuronal protection was significantly increased P7 cerebellar granule cells and E20 cortical cells on normoxia and hypoxia. 2. The effect of KM-B on neuronal protection was increased P7 cerebellar granule cells on normoxia, but was significantly decreased P7 cerebellar granule cells on hypoxia. The effect of KM-B on neuronal protection was non-significantly increased E20 cortical cells on normoxia and hypoxia. 3. The effect of KM-C on neuronal protection was non-significantly increased P7 cerebellar granule cells on normoxia and hypoxia and was decreased (p=0.058) on hyperconcentration of the extracts in normoxia. The effect of KM-C on neuronal protection was significantly increased P7 cerebellar granule cells and E20 cortical cells on normoxia and hypoxia (10 DIV), and the effect was E20 cortical cells on normoxia (14 DIV), non-significantly increased E20 cortical cells on hypoxia (14DIV). 4. The effect of KM-D on neuronal protection was increased P7 cerebellar granule cells on normoxia but was not on hyperconcentration of the extracts, was significantly decreased on hyperconcentration of the extracts in hypoxia. The effect of KM-D on neuronal protection was significantly increased E20 cortical cells on normoxia and was significantly increased E20 cortical cells increased on hypoxia (10 DIV). Conclusions : Goomicheongsim-won extracts had applicable effect on E20 corticells and P7 cerebellar cells exposed to hypoxia. The effect on neuronal protection by elimination of Rhinoceros unicornis L. and/or Orpiment $As_2S_3$ was changed.

• The Korean Journal of Physiology
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• 제2권1호
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• pp.23-30
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• 1968

Tissue homogenates of 12 kinds of human cancer tissues were incubated separately in medium containing $C^{14}-1-glucose$ and $C^{14}-6-glucose$ as a substrate in order to observe the oxidative pathway of glucose in the tumor tissues. At the end of 3 hours incubation in the Dubnuff metabolic shaking incubator, respiratory $CO_2$ samples trapped by alkaling which was placed in the center well of incubation flask were analysed for total $CO_2$ production rates and their radioactivities. The tissue homogenate samples after incubation were analyzed for their concentrations of glucose, lactate and pyruvate. Calculations were made on the glucose consumption rate and accumulation rates of lactate and pyruvate. Fractionation of oxidative pathway of glucose was carried out by calculating $C^{14}O_2 yields from C-1 and C-6 carbon of glucose. The following results were obtained. 1. In 12 kinds of human cancer, total $CO_2$ production rates were less than $8{\mu}M/gm$ except 2 cases. These lower values impressed that oxidative metabolism in the tumor tissues generally inhibited as compared with that in normal tissues. On the other hand, fractions of $CO_2$ derived from glucose to total $CO_2$ production rates (RSA) were less than 10% in every case. These facts showed that oxidation of glucose into $CO_2$ was remarkably inhibited in the tumor tissues. 2. Factions of glucose disappeared into $CO_2\;(RGD_{CO_2})$, lactate $(RGD_L)$, pyruvate $(RGD_P)$ to glucose consumption rates were as follows. $RGD_{CO_2}$ were less than 2% in cases of in this experiment and $RGD_L$ showed more than 5% except in 2 cases. These facts showed that anaerobic degradation of glucose into 3 carbon compounds was easily proceeded but further degradation into $CO_2$ via the TCA cycle was greatly inhibited resulting in accumulation of lactate. There are large variation in values of $RGD_P$ in different kinds of tumor tissue but relatively higher values in $RGD_{CO_2}$ were obtained in the tumor tissues as compared with those of normal tissues. 3. The oxidative pathway of glucose in tumor tissues were analyzed from the values of RSA which were obtained in $C^{14}-1\;and\;C^{14}-6-glucose$ incubation experiments. It was found that 3% of $CO_2$ derived from glucose were oxidized via the principal EMP-TCA cycle and the remainder were via alternate pathway such as HMP in the liver cancer and values in other cancer tissues were as follows; 4% in the tongue cancer, 6% in the colon cancer, 6% in the lung cancer, 9% in the stomach cancer, 11% in the ovarian cancer, 12% in the neck tumor, 22% in the uterine cancer, 22% in the bladder tumor, 32% in the spindle cell sarcoma and 65% in the brain tumor. These values except later 2 cases showed less than 30% which is the lowest value among the normal tissues. Even in the brain tumor in which showed highest value in the tumor group. It is reasonable to suppose that this fraction was remarkably decreased because values in normal brain tissue was more than 90%. From the above data, it was concluded that in tumor tissues, oxidation of glucose via TCA cycle was greatly inhibited but correlation between degree of inhibited oxidation of glucose via TCA cycle and malignancy of tumor were not clarified in this experiments.

• 한국버섯학회지
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• 제2권4호
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• pp.184-191
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• 2004

표고버섯은 Trichoderma spp.의 침입을 받으면 두 균이 접하는 부위에 다량의 laccase을 분비하여 갈색 대치선을 형성하는 것으로 알려져 있다. 하지만, 어떤 경우에는 이러한 갈변현상이 전혀 혹은 거의 나타나지 않거나 상대적으로 늦게 발현되기도 한다. 또한, 현장에서는 Trichoderma spp.의 종류에 의해 오염이 된 톱밥배지에서 갈색 대치선이 형성되지 않은 채 표고버섯에 따라 그리고 두 길항균이 처한 사항에 따라 표고버섯의 laccase 유도정도 및 갈변현상의 형성 및 변화 정도가 다른 것으로 나타났다. 본 연구는 표고버섯과 Trichoderma spp.의 균사가 서로 접한 부위에서 발생하는 두 균의 상호작용에 대해 다양하게 조사하였다. 1. YME 배지에서 표고버섯의 laccase 활성은 주로 10일 이후에 증가되기 시작하였고 20일을 기점으로 급격히 증가하였으며 30일을 전후하여 다시 감소하기 시작했다. 또한, laccase 활성도는 균체량 상관이 있었다. 2. 본 연구에 사용된 모든 Trichoderma spp.는 표고버섯의 laccase 활성을 촉진시켰으며 균주별로 약간의 차이가 있었다. 3. YMEA 배지에서 대치배양된 표고버섯은 모든 Trichoderma spp.의 침투에 대해 brown-line을 형성함으로써 길항작용을 보이면서 두 길항균은 서로의 균사생장을 억제하였으며 표고버섯의 균사생장이 더 억제되는 것으로 나타났다. 하지만, T12균주의 경우 6일 이하로 배양된 표고버섯의 영양균사의 갈색 대치선의 형성을 유도하지 못했다. 4. Brown-line 형성 이후 Trichoderma spp.의 영양균사는 표고버섯의 영양균사 위로 계속해서 생장을 하였으며 이때, 갈색 대치선은 Trichoderma spp. 영양균사의 정단부위 직전에 형성되면서 이동하였다. 하지만, T4와 표고버섯의 영양균사가 서로 근접했을 경우 뚜렷한 갈색 대치선이 먼저 형성되고 그 이후 서로의 영역을 침범(over-growing)하지 못했으며 갈색 대치선은 이동하지 않고 안정적이었다. 5. 두 길항균이 서로 대치한 지역의 laccase 활성율을 부위별로 조사한 결과 laccase 활성율은 Trichoderma류의 종류에 상관없이 모든 처리구에서 B, C, A의 순으로 나타났다. 6. 두 길항균이 서로 대치한 지역의 pH를 조사한 결과 표고버섯의 균사 분포지역의 pH는 4.3~4.4, T12, T13의 경우 pH 4.5~5.0, T1, T2, T5의 경우 pH 5.5~6.7의 범위였으며 두 길항균의 길항작용 지역의 경우 두 균이 갖는 pH 범위의 중간정도의 값을 나타냈다. 이러한 결과는, T12, T13의 경우 표고버섯의 갈변 현상 유도가 느리거나 거의 유도하지 않는 점을 고려한다면, 갈변 현상 형성에 있어서 길항균의 pH 범위가 중요한 역할을 하는 것을 추정할 수 있었다. 7. 미강이 첨가된 톱밥배지 상에 3, 6, 9cm 기배양된 표고버섯에 접종된 Trichoderma spp.는 모든 처리구에서 갈색 대치선을 형성하였다. 하지만, 한천배지에서와는 상반되게 대치 후 2~3일이 지나면 표고버섯의 영양균사는 Trichoderma spp.의 균사 위로 생장을 하였다. 또한, 이때 배지의 pH는 표고버섯의 점유지역의 경우 pH 4.0~4.5, Trichoderma spp.의 경우 pH 5.0~6.0, 그리고 갈색 대치선을 형성지역의 경우 pH 4.5~5.5의 범위였으나 표고버섯이 Trichoderma spp. 위로 생장한 지역의 pH는 4.3~4.8의 범위를 나타냈다.

• 대한한방종양학회지
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• 제6권1호
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• pp.81-97
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• 2000

Objectives: This experimental study was carried out to evaluate the effects of aqueous and methanol extracts of Hedyotis diffusa which has long been used for cancer treatment in oriental medicines on the induction of apoptotic cell death in human lymphoid leukemia cell line, HL-60. Methods: Cells were treated with various concentrations (200 to $0.4{\mu}g$) and periods (6 to 30 hr) of $H_2O$ and methanol extracts of Hedyotis diffusa. Then, cells were tested for viability by MTT assay. Cells wrere treated with $200{\mu}g/ml$ of methanol extract fork various periods. Genomic DNA was isolated, separated, on 1.5% agarose gels, stained with ethidium bromide and visualized under UV light. Cells were treated with $200{\mu}g/ml$ of each extract for 16 hr. Then, cells were treated with Hoechst dye 33342 and observed by fluorescence microscopy. Cells were treated with various doses of each for 12 hr and $100{\mu}g/ml$ of methanol extract for various periods. Lysate from the cells used to measure the activity of Caspase-1 and-3 proteases by using fluorogenic peptide substrates including acetyl-YVAD-AMC and acetyl-DEVD-AMC, respectively. Cells were treated with $200{\mu}g/ml$ of each extract for various periods. Cell lysates were immunoprecipated with anti-JNKl antibodies. The immune complex was reacted with $32^p-ATP$ and c-Jun as a substrate. The phosphotransferase activity of JNKI was measured by using PhosphoImage analyzer (Fuji Co., Japan). Nuclear extracts were isolated and incubated with oligonucleotide probe of $NF-{\kappa}B$. Transcriptional activation of ${\kappa}B$ was measured by using EMSA and visualized by PhosphoImage analyzer (Fuji Co, Japan). Cell lysates were prepared and analyzed by Western blotting with anti-Bc12 antibodies and anti-Bax antibodies. Cells were pretreated with various doses of methanol extract for 2 hr. Then, the extract was removed by centrifugation. Cells were resuspended with RPMI-1640 media containing 0.3% agarose, 10% FBS, overlayred onto bottom layer agarose and incubated at $CO_2$ incubator for 6 days. The number of colony was counted under light microscopy ($\time100$). Results: The death of HL-60 cells was markedly induced by the addition of methanol extract of Hedyotis diffusa in a dose and time-dependent manners. The apoptotic characteristic ladder pattern of DNA strand break was observed in death of HL-60 cells. In addition, it was shown nucleus chromatin condensation and fragmentation under Hoechst staining. Therefore, Hedyotis diffusa extract-induced death of HL-60 cells is mediated by apoptotic signaling processes. The activity of Caspase 3-like proteases remained in a basal level in HL-60 cells treated with aqueous extract of Hedyotis diffusa. However, it was markedly increased in HL-60 cells treated with methanol extract of Hedyotis diffusa. In addition, the phosphotransferase activity of JNKl was increased in HL-60 cells treated with methanol extract of Hedyotis diffusa. Furthermore, the activation of transcriptional activator, $NF-{\kappa}B$ was markedly induced by methanol extract of Hedyotis diffusa. Anti-apoptotic Bc12 was cleaved into 23Kda fragment by treatment of methanol extract of Hedyotis diffusa. However, expression of proapoptotic Bax protein was increased by treatment of methanol extract of Hedyotis diffusa in a time-dependent manner. Furthermore, methanol extract markedly inhibited the colony forming efficiency of HL-60 cells in semisolid agar culture. Conclusions: Above results suggest that methanol extract of Hedyotis diffusa induces the apoptotic death of human leukemic HL-60 cells via activations of Caspase-3 proteases, JNKI, transcriptional activator $NF-{\kappa}B$, In addition, our results also suggest that methanol extract of Hedyotis diffusa reduces the malignant potential of HL-60 cells via down regulation of colony forming effciency through cleavage of Bc12 as well as induction of Bax.

• 대한치과마취과학회지
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• 제14권1호
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• pp.49-56
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• 2014

Background: Propofol (2.6-diisopropylphenol) is a widely used intravenous anesthetic agent for the induction and maintenance of anesthesia during surgeries and sedation for ICU patients. Propofol has a structural similarity to the endogenous antioxidant vitamin E and exhibits antioxidant activities.13) However, the mechanism of propofol on hypoxia/reoxygenation (H/R) injury has yet to be fully elucidated. We investigated how P-PostC influences the autophagy and cell death, a cellular damage occurring during the H/R injury. Methods: The groups were randomly divided into the following groups: Control: cells were incubated in normoxia (5% CO2, 21% O2, and 74% N2) without propofol treatment. H/R: cells were exposed to 24 h of hypoxia (5% CO2, 1% O2, and 94% N2) followed by 12 h of reoxygenation (5% CO2, 21% O2, and 74% N2). H/R + P-PostC: cells post-treated with propofol were exposed to 24 h of hypoxia followed by 12 h of reoxygenation. 3-MA + P-PostC: cells pretreated with 3-MA and post-treated propofol were exposed to 24 h of hypoxia followed by 12 h of reoxygenation Results: The results of our present study provides a new direction of research on mechanisms of propofol-mediated cytoprotection. There are three principal findings of these studies. First, the application of P-PostC at the onset of reoxygenation after hypoxia significantly increased COS-7 cell viability. Second, the cellular protective effect of P-PostC in H/R induced COS-7 cells was probably related to activation of intra-cellular autophagy. And third, the autophagy pathway inhibitor 3-MA blocked the protective effect of P-PostC on cell viability, suggesting a key role of autophagy in cellular protective effect of P-PostC. Conclusions: These data provided evidence that P-PostC reduced cell death in H/R model of COS-7 cells, which was in agreement with the protection by P-PostC demonstrated in isolated COS-7 cells exposed to H/R injury. Although the this study could not represent the protection by P-PostC in vivo, the data demonstrate another model in which endogenous mechanisms evoked by P-PostC protected the COS-7 cells exposed to H/R injury from cell death.

• 한국환경농학회지
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• 제19권4호
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• pp.300-308
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• 2000

혐기적 토양조건하에서 제초제 $^{14}C-bifenox$의 분해를 조사하고자 하였다. $^{14}C-bifenox$를 미사질양토와 사양토에 각각 2.1 mg/kg 수준으로 처리한 후, 180일 동안 $25^{\circ}C$의 혐기적 조건하에서 배양하였다. 배양기간동안 bifenox의 무기화, 유기용매 추출성 및 추출불가 잔류량, 그리고 분해산물 등을 조사하였다. 배양기간 180일 동안 방출된 약제의 $^{14}CO_2$는 미사질양토와 사양토에서 각각 1.97%와 0.9% 수준이었다. 사양토에서의 추출불가 잔류량은 시험기간동안 표지된 $^{14}C$가 79.12%까지 눈에 띠게 증가하였고, 미사질양토에서 보다 그 양이 더 많았으며 이는 두 토양이 갖는 서로 다른 물리화학적 특성과 유기물 함량의 차이에서 기인된 것으로 판단되었다. 또한 추출불가 잔류량은 주로 humin에 분포하였으며 배양시간에 따라 증가하였다. 토양 중 bifenox의 주요 분해산물은 최종산물인 nitrofen, 5-(2,4-dichlorophenoxy)-2-nitrobenzoate 2,4-dichlorophenoxy aniline 그리고 methyl 5-(2,4-dichlorophenoxy) anthranilate으로 확인되었다. Bifenox의 토양 중 휘발성 물질 및 $CO_2$ 생성량과 잔류 및 분해독성은 이 화합물이 화학적 및 생물학적 분해에 안정함을 시사하였다.

• 한국식품과학회지
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• 제22권4호
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• pp.421-425
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• 1990

본 실험에서는 균주의 특성에 따른 유산균수 시험방법의 적합 여부를 알아보기 위해 액상요구르트 제품들을 유효기간 중 여러 실험조건으로 비교 검토하였다. 비교한 실험조건은 배지(BCP, Elliker agar), 배양상태(aerobic, anaerobic), 희석수(saline, phosphate buffer), 희석방법 (10배, 100배)이었으며 $37^{\circ}C$에서 72시간 배양하였다. L. acidophilus 균주를 사용한 액상요구르트의 경우, 배지와 희석방법에 따른 차이는 거의 없었고 희석수와 배양상태에서는 약간의 차이가 있었다. L. jugurti 균주와 L. acidophilus +L. casei 혼합균주의 생우 배지 배양상태, 희석수에서 차이가 있었고 희석방법에는 거의 차이가 없었다. L. casei의 경우 배지, 희석방법에서 약간의 차이를 나타했으며 배양상태는 유산균수에 영향이 없었다. L. bulgaricus의 경우는 배지, 배양상태, 희석방법에 따라 차이가 있었고 희석수는 차이가 없었다. 그러므로 요구르트의 유산균수 측정은 균주의 종류에 따라 가장 좋은 실험조건을 선택하여 실시하는 것이 효과적인 시험방법으로 사료된다.

• 농약과학회지
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• 제18권4호
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• pp.258-268
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• 2014

OECD Test guideline 307에 따라 확립한 토양대사 시험법으로, 호기성 토양 조건에서 [$^{14}C$]butachlor의 토양대사 시험을 실시하였다. 시험토양은 국내 밭토양의 대표적인 토성인 양토였으며, 비멸균 및 멸균토양에 [$^{14}C$]butachlor ($6.83mgKg^{-1}$)을 처리하고 flow-through system에서 60일간 배양하였다. 시험기간 동안 mass balance는 비멸균 토양과 멸균토양에서 각 처리방사능 대비 91.1~95.5%, 93.0~97.7% 수준이었다. 비멸균 토양의 경우 처리 후 60일 경과 시 처리방사능의 8.4%로 감소하였으며, $DT_{50}$과 $DT_{90}$은 10.4일과 34.6일이었다. 토양 추출액 중 주요대사산물 2-chloro-2',6'-diethylacetanilide이 검출되었다. $^{14}CO_2$ 및 비추출성 토양잔류물은 3.5%와 43.5% 수준이었다. 시험기간 중 멸균 토양 내 [$^{14}C$]butachlor의 분해는 거의 일어나지 않았다. 따라서 butahclor는 호기성 토양에서 미생물에 의해 빠르게 분해되어 주요 대사산물 2-chloro-2',6'-diethylacetanilide와 $CO_2$를 생성하거나 토양에 강하게 흡착되어 비추출성 잔류물로 존재하는 것으로 판단된다. 이를 통해 OECD guideline TG 307에 확립한 호기성토양대사 시험법은 농약의 위해성 평가를 위한 토양 동태 예측 있어 국내 활용에 적합할 것으로 판단된다.

• Journal of Korean Neurosurgical Society
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• 제29권9호
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• pp.1161-1170
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• 2000

Objective : The transverse hippocampal slice is one of the most commonly studied in vitro models of mammalian brain physiology. However, despite its broad usage, there has been no standardization of slice preparation techniques or recording condition. It is well known that variations in recording conditions can result in profound different effects to neuronal responses. Evoked field potentials, recorded extracellularly, were used to investigate the effects of variations in hippocampal slice preparation protocol on hypoxia responses of CA1 neurones. Material & Methods : Before hypoxic injury, hippocampal slices were incubated for 4 hours. During incubation period, the slices were placed in a incubation chamber($21^{\circ}C$) for recovery from preparation injury and then transferred to recording chamber($34^{\circ}C$) for more recovery and baseline electric recording with current stimulation(0.1Hz). Various time periods in incubation chamber and recording chamber were applied to each experimental group(group 1=60min : 180min, group 2=90min : 150min, group 3=180min : 60min, time in incubation chamber : time in recording chamber) before 10 min hypoxia produced by replacing 95% $O_2$+5% $CO_2$ mixed gas to 95% $N_2$+5% $CO_2$ gas. Calcium, Magnesium ions and several drugs effecting on glutamate receptor also were studied. Recoveries from hypoxic injury of hippocampal slices were estimated by percent recovery of population spike(PS). Statistic analysis of study were performed using paired t-test. Results : The percent recovery of PS after 10min hypoxia was considerably enhanced by increasing the period of current stimulation during incubation period before hypoxic injury. Temperature effect on the result of this experiment was also studied(group 4) but the result from this showed no statistic significance. Low magnesium ion concentration of artificial CSF(Mg-free aCSF) during incubation period enhanced the recovery of PS but low calcium (calcium-free) and high magnesium ion concentration(2mM) reduced it after hypoxic injury. L-glutamate($100{\mu}M$) and AP-5($50{\mu}M$) had no effect on the recovery of PS but CNQX($10{\mu}M$) in artificial CSF during incubation period markedly enhanced the recovery of PS. Co-treatment of AP-5($50{\mu}M$), CNQX($10{\mu}M$) and high magnesium concentration(2mM) enhanced recovery of PS in immediate following period of hypoxic injury but the effect of cotreatment after then decayed rapidly and lost statistic significance. Conclusions : Judging from above results, the condition of baseline recording is important in observing the recovery of population spike after hypoxia, and the time and the condition should be controled more strictly to obtain reliable results.