• 생명과학회지
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• 제20권12호
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• pp.1777-1783
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• 2010

식물체는 대사과정의 부산물로서 또는 생물학적으로 피해를 줄 수 있는 다양한 종류의 외부 스트레스에 직면했을 활성산소(Reactive Oxygen Species, ROS)를 생산한다. 이러한 oxidative 스트레스로부터 자신들을 보호하기 위하여 식물세포들은 다양한 종류의 항산화 단백질들을 보유하고 있다. 하지만 이들의 작용기작은 여전히 자세히 밝혀지지 않았다. Peroxiredoxins (Prxs)은 식물체에 광범위하게 존재하는 thiol-을 함유한 항산화 단백질로 N-말단에 존재하는 cysteine 잔기를 이용하여 hydrogen peroxide를 환원한다. 이러한 과정에서 peroxiredoxins의 활성부위인 cysteine 잔기는 선택적으로 cysteine sulfinic acid로 산화됨으로써 peroxidase activity의 불활성화를 일으킨다. 이러한 산화과정은 비가역적으로 일어난다. 최근 발견된 진핵생물들에 잘 보존된 sulphiredoxin (Srx1)이라 불리는 단백질은 cysteine-sulphinic acid를 환원시키는 기능을 지닌다. 본 논문에서는 애기장대에 존재하는 Prxs와 Srx의 기능에 대하여 서술할 예정이다.

• 한국식품위생안전성학회지
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• 제1권1호
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• pp.77-95
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• 1986

In 1962 the governing bodies of FAO and WHO approved the establishment of a joint FAO/WHO Food Standards Programme, the creation of a jointly sponsored body to be known as the Codex Alimentarius commission to implement the Programme. It can reasonably be claimed that the Commission has assumad the leading role in establishing internation food standards throughout the world. The Codex Committee of Food Hygiene has received much advice and assistance from other international organization which have been working in this field for a number of years. In particular, it has received valuable background documentation from the International Commission on Microbiological Specifications for Foods(ICMSF) which was set up by the International Association of Microbiological Societies(IAMS), and also from the International Organization for Standardization (ISO). Nevertheless, in spite of the information supplied by governments and research bodies in this field, microbiological standards have proved to be a highly controversial subject from the point of view of Codex standards. When it is decided to establish a microbiological standard for a food or class of foods, the following technical and administrative aspects must be considered: 1) The standard should be based on factual studies and serve one or more of the following objectives: (1) to determine the conditions of hygiene under which the food should be manufactured; (2) to minimize the hazards to public health; (3) to measure the keeping quality and storage potential of the food 2) The standard should be attainable under practicable operating and commercial conditions and should not entail the use of excessive heat treatment or the additions of extra preservatives. 3) The standard should be determined after investigation of the processing operation. 4) The standard should be as simple and inexpensive to administer as possible, the number of tests being kept to a minimum. 5) Details of methods to be used for sampling, examining and reporting should accompany all published microbiological standards. 6) In establishing tolerance levels for the permissible number of defective samples, allowance should be made for sampling and other variations due to differences in the laboratory methods. The following additional points should be kept in mind: 1) It is not satisfactory to establish one set of microbiological standards for a miscellaneous group of foods, such as“frozen foods”or“precooked foods”. 2) Microbiological standards should be applied first to the more hazardous types of food on the basis of experience of expected microbiological levels, taking into account variations in composition, processing procedures, and storage. 3) When a standard is established, there should be a definite relationship between the standard and the hazard against which it is meant to protect the public. 4) The sensitivity, reliability, and reproducibility of the sampling and analytical methods should be compared in different laboratories and the methods to be used should be specified in detail as part of the standard. 5) Tolerances should be included in the standard to account for inaccuracies of sampling and analysis. 6) Standards should be applied on a voluntary basis before compliance is made mandatory.

• 동의생리병리학회지
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• 제18권2호
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• pp.311-343
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• 2004

Various aspect of epidemics broke out continually from the middle of Joseon Dynasty due to the famine and drought caused by abnormal climate of the sixteenth century and the war. Thus the Dynasty performed sacrificial rites, isolated the patients and published plenty of medical books related epidemics in order to cure of the patients, and Heojun edited 『Byeokyeoksinbang』 as 'Dangdokyeok' broke out at Gwanbuk(關北) districts in 1613, Heojun explained the cause of Dangdokyeok as meteorology under the feudal conditions, and concluded Simhwa(心火) by fever toxin, Therefore he selected the method of puting out Simhwa by attack of fever toxin. In addition he presented emergency treatment that can maintain the airway by bleeding. To treat Dangdokyeok, Heojun presented lots of prescriptions so as Seungmagalgeuntang(升麻葛根湯), Cheongyeolhaedoksan(淸熱解毒散), Yeongyopaedok-san(連翹敗毒散), Bangpungtongsaongsan(防風通聖散), Jowiseunggitang(調胃升氣湯) and Hwangryeonhaedoktang(黃連解毒湯) etc. And he proposed Samdueum (三豆飮), Realgar(石雄黃) and so on to prevent infection from that. They presume from 120 to 150 years as the period of human adaptation to the first epidemics. Dangdokyeok put a large number of people to death at first, but it wasn't referred at the history any more after Byeokyeoksinbang. So we can say that the treatment of Heojun may be effective. Common cold and dyspeptic cold broke out in our country differently from 'Shanghan(傷寒)' in the China, so we had settled 'pestilence infectious epidemic disease(瘟疫)' while 'epidemic febrile disease(溫病)' of the China. Dangdokyeok of Heojun is similar to 'Scalet fever' belonging to 'virulent heat pathogen(溫毒)', 'newly epidemic febrile disease(新感溫病)'. As a cure of Dangdokyeok, the Korean medicine uses the treatment of removing fever state whereas the western medicine uses the antibiotics to kill the streptococcus. The symptoms of Dangdokyeok are remarkably similar to those of the Scarlatina, so this occupies a high position on the world history of medicine in aspects of the period and details of symptoms. These days we have the problems that the tolerance of antibiotics increases and disease of unknown cause is prevalent. It means the western medicine get to limits. So if we progress epidemiography based on Heojun's medicine, we may contribute to the world history of medicine.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.127-127
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• 2017

Aluminum is the most abundant metallic element in the Earth's crust and considered as the most limiting factor for plant productivity in acidic soils. The inhibition of root growth is recognized as the primary effect of Al toxicity. Seeds of wheat cv. Keumkang (Korean cultivar) were germinated on petridish for 5 days and then transferred hydroponic apparatus which was treated with $0{\mu}M$ $AlCl_3$ (control), $100{\mu}M$ $AlCl_3$ and $150{\mu}M$ $AlCl_3$ for 5 days. The length of roots, shoots and fresh weight of wheat seedlings were decreased under aluminum stress. The concentrations of $K^+$, $Mg^{2+}$ and $Ac^{2+}$ were decreased whereas $Al^{3+}$ and $P_2O_5{^-}$ concentration was increased under aluminum stress. Using confocal microscopy, the fluorescence intensity of aluminum was increased with morin staining. In this study, a proteome analysis was performed to identify proteins, which is responsible to aluminum stress in wheat roots. In 10-day-old seedlings, proteins were extracted from roots and separated by 2-DE, stained by CBB. Using image analysis, a total of 47 differentially expressed protein spots were selected, whereas 19 protein spots were significantly up-regulated such as s-adenosylmethionine, oxalate oxidase, malate dehydrogenase, cysteine synthase, ascorbate peroxidase and 28 protein spots were significantly down-regulated such as heat shock protein 70, o-methytransferase 4, enolase, amylogenin by aluminum stress following protein spots analyzed by LTQ-FTICR mass spectrometry. The results provide the global picture of Al toxicity-induced alterations of protein profiles in wheat roots, and identify the Al toxicity-responsive proteins related to various biological processes that may provide some novel clues about plant Al tolerance.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.20-20
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• 2017

Plant genomes include heterochromatic loci that consist of repetitive sequences and transposable elements. LTR retrotransposon is the major class of transposons in advanced plants in terms of proportion in plant genome. The elements contribute not only to genome size but also to genome stability and gene expression. A number of cases have been reported transposon insertions near genic regions affect crop traits such as fruit pigments, stress tolerance, and yields. Functional LTR retrotransposons produce extrachromosomal DNA from genomic RNA by reverse transcription that takes place within virus-like-particles (VLPs). DECREASED DNA METHYLATION 1 (DDM1) plays important roles in maintaining DNA methylation of heterochromatin affecting all sequence contexts, CG, CHG, and CHH. Previous studies showed that ddm1 mutant exhibits massive transcription of retrotransposons in Arabidopsis, but only few of them were able to create new insertions into the genome. RNA-dependent RNA POLYMERASE 6 (RDR6) is known to function in restricting accumulation of transposon RNA by processing the transcripts into 21-22 nt epigenetically activated small interfering RNA (easiRNA). We purified VLPs and sequence cDNA to identify functional LTR retrotransposons in Arabidopsis ddm1 and ddm1rdr6 plants. Over 20 LTR copia and gypsy families were detected in ddm1 and ddm1rdr6 sequencing libraries and most of them were not reported for mobility. In ddm1rdr6, short fragments of ATHILA gypsy elements were detected. It suggests easiRNAs might regulate reverse transcription steps. The highest enriched element among transposon loci was previously characterized EVADE element. It has been reported that active EVADE element is more efficiently silenced through female germline than male germline. By genetic analyses, we found ddm1 and rdr6 mutation affect maternal silencing of active EVADE elements. DDM1-GFP protein accumulated in megaspore mother cell but was not found in mature egg cell. The fusion protein was also found in early embryo and maternal DDM1-GFP allele was more dominantly expressed in the embryo. We observed localization of DDM1-GFP in Arabidopsis and DDM1-YFP in maize and found the proteins accumulated in dividing zone of root tips. Currently we are looking at cell cycle dependency of DDM1 expression using maize system. Among 10 AGO proteins in Arabidopsis, AGO9 is specifically expressed in egg cell and shoot meristematic cells. In addition, mutation of AGO9 and RDR6 caused failure in maternal silencing, implying 21-22 nt easiRNA pathway is important for retrotransposon silencing in female gametophyte or/and early embryo. On the other hand, canonical 24 nt sRNA-directed DNA methylation (RdDM) pathways did not contribute to maternal silencing as confirmed by this study. Heat-activated LTR retrotransposon, ONSEN, was not silenced by DDM1 but the silencing mechanisms require RdDM pathways in somatic cells. We will propose distinct mechanisms of LTR retrotransposons in germline and somatic stages.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.97-97
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• 2017

Plant genomes include heterochromatic loci that consist of repetitive sequences and transposable elements. LTR retrotransposon is the major class of transposons in advanced plants in terms of proportion in plant genome. The elements contribute not only to genome size but also to genome stability and gene expression. A number of cases have been reported transposon insertions near genic regions affect crop traits such as fruit pigments, stress tolerance, and yields. Functional LTR retrotransposons produce extrachromosomal DNA from genomic RNA by reverse transcription that takes place within virus-like-particles (VLPs). DECREASED DNA METHYLATION 1 (DDM1) plays important roles in maintaining DNA methylation of heterochromatin affecting all sequence contexts, CG, CHG, and CHH. Previous studies showed that ddm1 mutant exhibits massive transcription of retrotransposons in Arabidopsis, but only few of them were able to create new insertions into the genome. RNA-dependent RNA POLYMERASE 6 (RDR6) is known to function in restricting accumulation of transposon RNA by processing the transcripts into 21-22 nt epigenetically activated small interfering RNA (easiRNA). We purified VLPs and sequence cDNA to identify functional LTR retrotransposons in Arabidopsis ddm1 and ddm1rdr6 plants. Over 20 LTR copia and gypsy families were detected in ddm1 and ddm1rdr6 sequencing libraries and most of them were not reported for mobility. In ddm1rdr6, short fragments of ATHILA gypsy elements were detected. It suggests easiRNAs might regulate reverse transcription steps. The highest enriched element among transposon loci was previously characterized EVADE element. It has been reported that active EVADE element is more efficiently silenced through female germline than male germline. By genetic analyses, we found ddm1 and rdr6 mutation affect maternal silencing of active EVADE elements. DDM1-GFP protein accumulated in megaspore mother cell but was not found in mature egg cell. The fusion protein was also found in early embryo and maternal DDM1-GFP allele was more dominantly expressed in the embryo. We observed localization of DDM1-GFP in Arabidopsis and DDM1-YFP in maize and found the proteins accumulated in dividing zone of root tips. Currently we are looking at cell cycle dependency of DDM1 expression using maize system. Among 10 AGO proteins in Arabidopsis, AGO9 is specifically expressed in egg cell and shoot meristematic cells. In addition, mutation of AGO9 and RDR6 caused failure in maternal silencing, implying 21-22 nt easiRNA pathway is important for retrotransposon silencing in female gametophyte or/and early embryo. On the other hand, canonical 24 nt sRNA-directed DNA methylation (RdDM) pathways did not contribute to maternal silencing as confirmed by this study. Heat-activated LTR retrotransposon, ONSEN, was not silenced by DDM1 but the silencing mechanisms require RdDM pathways in somatic cells. We will propose distinct mechanisms of LTR retrotransposons in germline and somatic stages.

• 한국축산식품학회지
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• 제27권3호
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• pp.363-370
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• 2007

김치의 L. plantarum의 생균제적 특성을 조사하기 위하여 김치에서 산생산과 성장능력 등이 우수한 25종의 Lactobacillus sp.를 분리하였고, API kit 분석에 의하여 L. plantarum을 동정하고 재차 16S rDNA 염기서열(99.9% 상동성)을 비교한 후 L. plantarum JK-01로 표기하였다. L. plantarum JK-01은 MRS broth에서 배양시 18시간 후 $2.9{\times}10^{10}CFU/ml$로 최대로 증식하는 빠른 성장특성을 나타냈으며 pH도 4.5로 조속히 하강하였다. 효소활성은 xylanase, amylase, protease, phytase의 순으로 높은 활성을 포함하고 있는 것으로 예측되었다. L. plantarum JK-01은 pH 2에서도 $1.36{\times}10^5CFU/mL$가 생존하였고, 1%의 담즙산에서도 약 $10^6CFU/mL$이상이 생존하여 내산성과 내담즙산성이 강한 것으로 나타났다. 또, $60^{\circ}C$에서도 $3.3{\times}10^3$ CFU/mL 정도로 생존하는 내열성이 있었으며, 대장균과 함께 배양시 18시간 후 대장균을 사멸시키는 것으로 나타났다. 이상의 결과로부터 분리한 L. plantarum JK-01은 생균제로서 충분히 이용가치가 있는 것으로 사료되었다.

• 한국정보과학회:학술대회논문집
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• 한국정보과학회 2007년도 한국컴퓨터종합학술대회논문집 Vol.34 No.1 (B)
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• pp.273-278
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• 2007

검사점 및 복구 도구(Checkpointing & Recovery Facility)를 이용하여 임베디드 시스템에서 결함 허용(Fault Tolerance) 기법을 적용할 경우 쓰기 작업의 오버헤드로 인해 실용성이 크게 떨어지게 된다. 실시간 운영체제와 함께 어떠한 한계 상황에서 결함 허용 및 복구 도구가 오히려 시스템의 성능을 저하시키는 요인으로 작용하게 되면 이는 결국 쓸모없는 도구가 되어 사용되지 않을 것이다. 따라서 프로세스의 복구를 위해 저장하는 프로세스 이미지의 기록에 소요되는 시간을 크게 낮추어야만 비로소 검사점 도구가 그 진가를 발휘하게 될 수 있다. 본 논문에서는 NVSRAM(Non Volatile SRAM)을 검사점 및 복구 도구의 저장 장치로 활용함으로써 기존의 검사점 도구에서 성능을 저하시키는 주원인이었던 검사점 기록의 오버헤드를 개선하기 위한 연구를 수행하였다. 검사점 기록 시간을 줄이기 위한 방법으로 주 메모리에 저장된 프로세스의 복구와 관련된 데이터를 SRAM 특성을 갖는 비휘발성 저장 장치인 NVSRAM에 저장하여 디스크 접근에 소요되는 시간을 최소화시킴으로써 임베디드 시스템에서 실용적으로 사용 가능한 검사점 도구를 구현하였고, 이러한 연구의 결과를 검증하기 위해 기존 시스템에서 저장 장치로 사용되던 플래시 메모리, 주 메모리, 원격 메모리를 사용하는 경우의 성능과 NVSRAM을 활용할 때의 성능을 비교해 보았다. 본 연구에서 제안하는 결함 허용 도구는 실제 시스템에 적용하여 효과적인 성능을 발휘할 수 있을 것이며, 차세대 메모리를 이용한 결함 허용 도구의 연구에 기여를 할 수 있을 것으로 기대된다.ate첨가배지(添加培地)에서 가장 저조(低調)하였다. vitamin중(中)에서는 niacin과 thiamine첨가배지(添加培地)에서 근소(僅少)한 증가(增加)를 나타내었다.소시켜 항이뇨 및 Na 배설 감소를 초래하는 작용과, 둘째는 신경 경로를 통하지 않고, 아마도 humoral factor를 통하여 신세뇨관에서 Na 재흡수를 억제하는 작용이 복합적으로 나타내는 것을 알 수 있었다.으로 초래되는 복합적인 기전으로 추정되었다., 소형과와 기형과는 S-3에서 많이 나왔다. 이상 연구결과에서 입도분포가 1.2-5mm인 것이 바람직한 것으로 나타났다.omopolysaccharides로 확인되었다. EPS 생성량이 가장 좋은 Leu. kimchii GJ2의 평균 분자량은 360,606 Da이었으며, 나머지 두 균주에 대해서는 생성 EPS 형태와 점도의 차이로 미루어 보아 생성 EPS의 분자구조와 분자량이 서로 다른 것으로 판단하였다.TEX>개로 통계학적으로 유의한 차이가 없었다. Heat shock protein-70 (HSP70)과 neuronal nitric oxide synthase (nNOS)에 대한 면역조직화학검사에서 실험군 Cs2군의 신경세포가 대조군 12군에 비해 HSP70과 nNOS의 과발현을 보였으며, 이는 통계학적으로 유의한 차이를 보였다(p<0.05). nNOS와 HSP70의 발현은 강한 연관성을 보였고(상관계수 0.91, p=0.000), nNOS를 발현하는 세포가 동시에 HSP70도 발현함을 확인할 수 있었다. 결론: 우리는 cyclosporin A가 토끼의 25분간의 척수허혈에 대해 척수보호 효과가 있었으며 이는 HSP70의

• The Korean Journal of Physiology
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• 제4권1호
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• pp.19-28
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• 1970

In order to investigate the changes in the temperature regulation mechanism following ingestion of red pepper, twenty healthy man were given 2 gms of powdered red pepper each in 100 ml of water at room temperature, $20^{\circ}C$, Simultaneous recordings of temperature and electrical resistance of the skin of forehead were taken by means of Physiograph, using appropriate transducers. Temperature of various spots such as the cheek, upper tack and the forearm was also measured by the telethermometer at interval of two minutes. The results obtained were as follows: 1. Seventeen out of 20 subjects showed immediate rise in the skin temperature of the forehead, and 11 of them manifested the oscillating pattern of the skin temperature. The average of the largest peak amplitude was $0.58{\pm}0.355^{\circ}C$. 2. Even those who failed to show the immediate rise in the temperature did not keep the quiescence over 9 minutes, and delayed responses were revealed. 3. The rise in tile skin temperature is the favourable sign for the heat discipating mechanism only because the sweat glands are activated with the concomittant rise in the temperature of the skin. 4. There was a preceding or coincide fall in the electrical resistance of the skin, and it was also attributed to the glandular activity. 5. At rather cool room temperature, $20^{\circ}C$, no visible sweat was seen during the period of observation. Nevertheless it was obvious that latent activation of the sweat glands was triggered and the. threshold was lowered. This situation imitates the acclimatized condition in the hot environment, and it is likely to increase the tolerance in tropical climate from the view point of temperature regulation.

• 한국미생물·생명공학회지
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• 제41권1호
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• pp.119-127
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• 2013

선행연구에서 김치발효 후기의 우점종으로 알려진 Lactobacillus sakei의 생육을 저해하는 Leuconostoc 속 23균주와 Weissella 속 45 균주를 김치로부터 분리, 동정하였다. 발효 후기까지 생존할 수 있는 김치발효용 hetero 발효형 종균 선발을 위하여 이들 균주에 대한 내산성을 평가한 결과, Lc. mesenteroides CK0128, W. cibaria CK0633, W. cibaria KK0797 균주가 acetic acid와 lactic acid 혼합용액을 이용하여 pH를 4.3으로 조정한 MRS broth에서 상대적으로 높은 생존율을 보였고, 다량의 세포 외 다당류를 생산하였다. 세균주가 생산하는 항균물질의 분자량은 3,000 Da 이하로 추정되며 Staphylococcus aureus와 Lb. sakei에 대한 생육저해를 나타내었다. 분획한 3,000 Da 이하의 조항균물질 모두가 $121^{\circ}C$, 15분의 열처리에도 항균활성을 유지함으로써 항균물질의 열에 대한 높은 안정성이 확인되었다. pH의 감소에 따른 항균활성의 증가가 pH 5 이하의 산성조건에서 확인되어, 이들 항균물질은 pH 5 이하의 산성조건에서 활성을 갖는 것으로 추정된다. ${\alpha}$-amylase, lipase, pepsin, proteinase K 처리가 항균활성에 아무런 영향을 미치지 않는 것으로 보아 이들 균주가 생산하는 항균물질은 탄수화물, 지질을 포함하지 않으며, 비단백질성 물질로 추정된다. 또한, 선발균주가 생산하는 비단백질성 항균물질은 식중독균의 생육을 효과적으로 저해하였다.