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Improvement in Antagonistic Ablility of Antagonistic Bacterium Bacillus sp. SH14 by Transfer of the Urease Gene. (Urease gene의 전이에 의한 길항세균 Bacillus sp. SH14의 길항능력 증가)

  • 최종규;김상달
    • Microbiology and Biotechnology Letters
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    • v.26 no.2
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    • pp.122-129
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    • 1998
  • It were reported that antifungal mechanism of Enterobacter cloacae is a volatile ammonia that produced by the strain in soil, and the production of ammonia is related to the bacterial urease activity. A powerful bacterium SH14 against soil-borne pathogen Fusarium solani, which cause root rot of many important crops, was selected from a ginseng pathogen suppressive soil. The strain SH14 was identified as Bacillus subtilis by cultural, biochemical, morphological method, and $API^{circledR}$ test. From several in vitro tests, the antifungal substance that is produced from B. subtilis SH14 was revealed as heat-stable and low-molecular weight antibiotic substance. In order to construct the multifunctional biocontrol agent, the urease gene of Bacillus pasteurii which can produce pathogenes-suppressive ammonia transferred into antifungal bacterium. First, a partial BamH I digestion fragment of plasmid pBU11 containing the alkalophilic B. pasteurii l1859 urease gene was inserted into the BamH I site of pEB203 and expressed in Escherichia coli JM109. The recombinant plasmid was designated as pGU366. The plasmid pGU366 containing urease gene was introduced into the B. subtilis SH14 with PEG-induced protoplast transformation (PIP) method. The urease gene was very stably expressed in the transformant of B. subtilis SH14. Also, the optimal conditions for transformation were established and the highest transformation frequency was obtained by treatment of lysozyme for 90 min, and then addition of 1.5 ${mu}g$/ml DNA and 40% PEG4000. From the in vitro antifungal test against F. solani, antifungal activity of B. subtilis SH14(pGu366) containing urease gene was much higher than that of the host strain. Genetical development of B. subtilis SH14 by transfer of urease gene can be responsible for enhanced biocontrol efficacy with its antibiotic action.

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A study on the Logical Reclassification of Parcel Service Tariffs (택배요금기준의 합리적 재설정에 관한 연구)

  • Cho, Yoon-Sung;Lee, Tae-Hwee
    • Journal of Distribution Science
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    • v.10 no.5
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    • pp.45-55
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    • 2012
  • In Korea, the parcel delivery service was launched officially in 1992, and the market has grown to 13.2 billion units, or 3.5 trillion won, as of 2011. The service companies accept small packages under 30 kg and deliver them on the next day in most domestic areas. This service plays an important role in business and personal activities. The parcel service companies have themselves designed the tariff for the delivery service based on two criteria: weight and the sum of three side lengths. Further, the tariff is graded in steps of three or four rate structures based on size (small, medium, large, and extra-small). However, the basic freight rate is generally decided according to the cargo's weight or measurement size, and an extra rate is added according to some factors (handling, stowability, liability, and so on). The parcel service tariff adopted by the companies is illogically designed, and this study was carried out to assess the need for redesigning the tariff structure. The cargo volume cannot be logically reflected by three side lengths. For example, two parcels measuring 160 cm based on three side lengths may have different volumes, one measuring 0.152 cbm (53.33 cm × 53.33 cm × 53.34 cm) and the other 0.05 cbm (100 cm × 50 cm × 10 cm). A small package of less than120 cm (sum of three side lengths) may have a volume of as much as 0.064 cbm (40 cm × 40 cm × 40 cm). Sample comparison showed that 17% of medium-size parcels (based on the sum of three side lengths) are small-volume packages, 24% of large-size parcels are small- or medium-volume packages, and 40% of extra-big-size parcels are big- or under-size packages. Therefore, if parcel service companies rate their services for volume cargo based on the three side lengths standard, users may have to pay higher than normal rates, particularly because a large percentage of parcels are volume cargo. According to this study, the average weight per 1 cbm is less than 300 kg. Therefore, users face an increasing risk of paying higher than logical freight charges. Generally, transportation companies are called "public interest enterprises," and parcel service companies operate as postal services. Public interest enterprises must provide the delivery service to all customers without discrimination at a reasonable service level and logical service charges. Therefore, parcels service tariffs must be designed and adopted logically. In this study, freight theories and prior research findings were used to consider the importance of freight rates, and distortion of parcel service rates based on the three side lengths system was verified through regression analysis of a parcel sample and sample comparison. In conclusion, volume sizes based on three side lengths have a higher correlation to the rate level than does the sum of three side lengths. Further, compared to the sum of three side lengths, volume size has a higher correlation to cargo weight, which is the most basic factor determining transportation cost. Therefore, the existing parcel service tariff should be changed to weight- and volume-based rates, and the tariff must be graded in steps of 8 to 10 higher rate structures for a logical freight schedule based on service cost.

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Present and Future of the Journal of Distribution Science (유통과학연구의 현재와 미래)

  • Kim, Dong-Ho;Youn, Myoung-Kil
    • Journal of Distribution Science
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    • v.10 no.5
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    • pp.7-17
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    • 2012
  • The recent announcement of the National Research Foundation of Korea (NRF) to cease journal accreditation operations as of the end of the year 2014 can easily influence the future of many research journals in Korea. Although this plan has not yet been formalized or structured, its facilitation would be the major turning point for the current Korean research and scholarly journals and publications. In addition, the NRF's plan to select and fund top 20 or more research journals over the five year period beginning 2015 suggests that the competition will most likely increase among Korean journals. Each journal would need to develop its unique strategy to improve and strengthen its competitiveness to become or maintain its position as a major research journal in Korea. The association of Korean Distribution of Science (KODISA) and its research journal, Journal of Distribution Science (JDS), has been continuously improving its reputation as a reputable journal in the distribution and related fields since its establishment in 1999. Due to demand, JDS has had to undergo several changes in its publication cycle first from semiannual publication to quarterly, then finally to monthly publications in 2012, and has become one of the major social science journals in Korea. Furthermore, with the redesigning of its webpage with English language in July of 2011, KODISA has made the published journals freely accessible and available to both domestic and foreign researchers, scholars, practitioners, and learners. These changes have resulted in the rapid increase in the bounce rate and the number of journal submissions by foreign scholars, with four research articles having been submitted by foreign scholars just in March of 2012 alone. However, although the changes and outcomes have resulted in a reasonable success so far, the achievement may only become a short-term success without continuously developing, improving, and implementing both effective and efficient strategies through critical, thorough, and frequent examinations and evaluations of both KODISA and JDS. As such, the purpose of this research is to carefully examine both KODISA and JDS to identify problematic factors and to develop appropriate strategies to change or modify those problems for further strengthening and improving their reputation and status. The paper examines and analyzes the past, present, and future of KODISA and JDS and their managerial, operational, and systematic procedures and operations. The narrow scope of research and inefficiencies in promoting the association and the journal and the improvement of impact factors are identified as the notable problems that could hinder JDS from being included in SCOPUS or SSCI in the near future. This type of examination and exploration has not been previously conducted, so the major limitation of this paper can be identified as not meticulously elaborating on the problems nor proving detailed recommendations based on the existing researches. This article asserted that solving the problem of the narrow scope of research would lead to facilitation of resolving other inefficient problems. Inclusion of international academic disciplines to the distribution and their related fields would be the viable initiation of expanding the research area, and this strategy could promote the journal as well as improve its impact factors. The narrow scope of research seems to be a good research topic and merit further exploration as an individual research project, because this kind of research could yield the creation of new understandings or theories.

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Generic Characters of Vertebrae and Pterygiophore of the Fishes of the Family Tetraodontidae (Teleostei: Tetraodontiformes) (참복과(복어목) 어류의 속별 척추골과 담기골 특징)

  • HAN Kyeong-Ho;KIM Yong Uk
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.31 no.5
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    • pp.645-653
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    • 1998
  • Twenty seven species of pufferfishes (family Tetraoaontidae) have been examined to find their generic characters based on vertebrae and pterygiophore characters of specimens collected in 20 localities along the coast of Korea from March, 1991 to March, 1994. It was divided by 3 groups based on vertebrae number as follow : the genera Lagocephalus, Pleurancanthus, Spheoides, Arothron, Chelonoeon and Canthigaster have 17$\~$19 vertebrae, genera Ephippion, Boesemanichthys and Feroxodon have 20 vertebrae, and genus Takifugu have 19$\~$25 vertebrae, The number of vertebrae ranged from 17 to 25 with the maximum of 25 in Takifugu obscurus. The modal number of vertebrae in Lagocephalus is 17 (L. lunaris), 18 (L. inermis), and 19 (L. gloveri, L. wheeleri, L. larigatus), with the lower number more specialized. Paired neural spines appear at number of the 1st$\~$5th vertebrae in Takifugu pardalis, Takifugu obscurus and at number of the 1 st$\~$4 th vertebrae in the other species and genera. All of the species of Lagocephalus and Pleurancanthus have dorsal and ventral pterygiophores processes, and flat-shaped epural, while none of the abdominal vertebrae processes complete haemal arches. The neural and haemal spines of the last few caudal vertebrae aye shorter in Pleurancanthus than in the other genera, associated with the depressed caudal peduncle. The genus Canthigaster is distinguished the first pterygiophores of the dorsal and ventral fins is always much larger than the others genera. Based on the haemal arches and spines of the abdominal vertebrae, genus Canthigaster has different characters from the other genera of the family Tetraodontidae.

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Basic Studies on Developing Equipment for Waterless Transportation of Live Fish (활어의 무수 수송 장치 개발을 위한 기초적 연구)

  • CHO Young-Je;KIM Yuck-Yong;LEE Nam-Geoul;CHOI Yeung-Joon
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.27 no.5
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    • pp.501-508
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    • 1994
  • This study was undertaken to get basic data for the cold-waterless transportation of live fish. The optimal cold temperature of plaice, Paralichthy olivaceus was determined by checking the changes of dissolved oxygen and ammonia in the sea water and the survival times during storage at various temperatures. After determination of optimal temperature for transportation, the changes of serum components and muscle components of live plaice were also carried out during storage at cold($5^{\circ}C$)-waterless conditions and the recovery conditions($10\%$ density at $15^{\circ}C$). At higher storage temperature, decreases in dissolved oxygen and the increases in ammonia in seawater were observed. In addition, the survival time was short at low temperature($0^{\circ}C\;and\;3^{\circ}C$). Almost all of the serum components(hemoglobin, glucose, LDH, GOT and GPT) of live plaice gradually increased during storage in cold-waterless conditions, and then those values decreased to the initial levels after $3{\sim}10hrs$ storage in conditions of recovery. The concentration of ATP in the muscle steadily decreased during storage in cold-waterless conditions. The contents of ADP and IMP seemed to be directly related to the extent of ATP breakdown. ADP and IMP thus showed a gradual increase during storage. The level of lactate in the muscles gradually increased during these storage times, also. On the other hand, the levels of those components in the muscle entirely recovered to their original levels within $3{\sim}6hrs$ storage after they were returned to conditions of recovery. The ratio of ATP to the ATP and its related compounds${ATP/(ATP+ADP+AMP+IMP){\times}100}$ in the muscle showed $45\%$ after 18hrs storage in cold-waterless conditions. Otherwise, ratios returned to their original levels within $3{\sim}6hrs$ of storage in recovery conditions.

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Variations of Fish Community and Fish Density on Artificial Reefs (인공어초어장의 어류 군집상과 어획량 변동)

  • LEE Jeong-Woo;KANG Young-Shil
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.27 no.5
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    • pp.535-548
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    • 1994
  • Community structures and fish densit were investigated on three different types of artificial reefs, dice, turtle artificial reef and tubes, constructed in the Korean waters. Variations of fish fauna according to type of artificial reef and the proper artificial reef in each area for optimizing harvest were discussed. Fish were captured by trammel gill net during May, June, September and November, 1988 and both identified and counted. Fourty-five fish species were found in the artificial reefs. Of these, Sebastes spp., Hexagrammos otakii, Pleuronectidae, Navodon modestus and Stephanolepis cirrhifer showed high occurrence-frequency. The dominant species groups were coastal settlement, demersal or rock fishes such as Pleuronectidae, Rajiformes, Stephanolepis cirrhifer, Navodon modestus, Hexagrammos otakii and Sebastes spp. in all of the Artificial reefs except the oceanic area of southern waters. Scomber japonicus was predominant in the oceanic area of southern waters. Composition of demersal, rock and pelagic fishes were different depending on the types of artificial reef. Dice artificial reefs were occupied by rock fish, on the other hand turtle artificial reefs were dominated by dermersal fish. Fish density was high at the dice artificial reef in all survey areas except the middle area of Eastern waters, with high fish density evident in the Tube artificial reef. Fish community structures were remarkably different between Dice and Turtle artificial reefs. The Tube artificial reef showed intermediate characteristics between the above two types of artificial reefs. The coastal areas of Southern waters and the middle and southern areas of Western waters revealed similar fish fauna. Results from the oceanic areas of Southern waters were well associated with the middle and southern areas of Eastern waters.

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Quality Improvement of Rainbow Trout with Pigments and Enzymatic Hydrolysates of Ascidian (Halocynthia roretzi) Tunic 1. Chemical Specificity of Ascidian Tunic and Its Hydrolysates (우렁쉥이 껍질의 색소 및 효소 가수분해물을 이용한 무지개 송어의 품질 향상 1. 우렁쉥이 껍질 및 효소 가수분해물의 화학적 특성)

  • CHOI Byeong-Dae;KANG Seok-Joong;LEE Kang-Ho
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.29 no.3
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    • pp.345-356
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    • 1996
  • Properties of enzymatic hydrolysates from ascidian tunic were assessed on supernatant ratio, solid yields and solid concentration. The concentartion of solid and yields in the extracts were increased as the enzyme concentration raised from $100\;{\mu}l\;to\;1000{\mu}l$ during the extraction period. The optima concentration and reaction time of each enzyme on digestion were $400\;{\mu}l$ 60 minutes, through treated with Duncan's multiple test. The percent of yields of solid, protein and carotenoids for 60 minutes extraction at $400\;{\mu}l$ were $32.32\%,\;1.34\%\;and\;74.60\;mg\%$, respectively, in Viscozyme systems. The extracts were composed with many kinds of carbohydrates such as arabinose, ribose, xylose, galactose, glucose, N-acetyl-D-galactosamine, and N-acetyl-D-glucosamine. Aspartic and glutamic arid were noted as predominant amino acids in all parts. Amino acid profiles of various ascidian tunic part were similiar to each other, but most of essential amino acids content of inter coat was higher than that of root and tunic (body). About sixty six fatty acids components were observed, and their distribution among neutral and polar lipids was compared. The main fatty acids were found to be 14:0, 16:0, 16:1n7, 18:0, 18:1n9, 18:1n7, 18:2n6, 20:5n3, and 22:6n3.

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The Spatio-Temporal Progress of Cochlodinium polykrikoides Blooms in the Coastal Waters of Korea (한국연안의 Cochlodinium polykrikoides 적조 발생과 변천)

  • KIM Hak Gyoon;JUNG Chang-Su;LIM Wol-Ae;LEE Chang-Kyu;KIM Sook-Yang;YOUN Sung-Hwa;CHO Yong-Chul;LEE Sam-Geun
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.34 no.6
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    • pp.691-696
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    • 2001
  • The first bloom of Cochlodinium polykrikoides was observed in the estuary of Nak-dong river near Pusan in Korea in 1982. Since then, there have been irregular blooms, sometimes spread over the adjoining .to Jinhae Bay even though it was confined to the bay and its vicinites until 1988. It had been outbroken frequently in the adjacent to Tongyeong, Geoje, Namhae and Yeosu coast since 1989. It became widespread along the coast of the South Sea to the East Sea of Korea in 1995. And in October in 1998 and 1999, the bloom had been taken place in Kunsan coast of Yellow Sea. According to the observations in situ, the frequency of occurrence has been increased year by year. The prevailing bloom season was from July to October with peak in September. The duration of the bloom became longer with the year, and sometimes lasted more than one month. The density of the bloom did not exceed 5,000 cells $mL^{-1}$until 1991, but it increased year by year to the highest of 43,000 cells $mL^{-1}$ in 1999. With respect to the assembleges of species in dinoflagellate blooms, C. polykrikoides was one of the important species with diatoms and the other dinoflagellates in 1980s. But since then, C. polykrikoides made an almost monospecific bloom. Based on two decadal observations of C. polykrikoides blooms, it became widespread throughout whole coast of the Korea, persistent for about one or two month long in some year, and monospecisc high density blooms. It was reported that significant fish mortalities were caused by this harmful dinoflagellate blooms especially in the fishfarms accomodating intensive fish cages such as Tongyeong, Namhae-do, Geoje, Yeosu and Geomun-do fishfarming yards. This widespread and persistent harmful algal blooms impede the development of marine aquaculture industries.

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The Characteristics and Landscape Meanings of Letters Carved on the Rocks of Mt. Sangdu (상두선(象頭山) 바위글씨의 특징과 경관의미)

  • Rho, Jae-Hyun;Lee, Jung-Han;Huh, Joon;Kim, Jeong-Moon
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.30 no.2
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    • pp.1-13
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    • 2012
  • This study aimed at learning the values and meanings of the letters carved on the rocks all over Mt. Sangdu located at the boundary between Kimje-si and Jeongeup-si of Jeollabuk-do by grasping the current state of them, investigating the patterns and contents of them, and understanding the spatial and landscape properties of the region where the rocks are scattered. The results of this study are as follows; The name of Mt. Sangdu came from the mountain with the same name located in India where Buddha were seeking the truth, and means auspicious. With the recognition of ancient maps and books, various propitious spots also made the landscape symbols of Mt. Sangdu solidify. Whoam, Chaangsuk-Kim, Weolgye Young-Cho Song and the members of Cheonggye Society like Dongcho Seok-Gon Kim led the creation of the rocks, and the 41 letter-carved rocks all over four water systems were found out and all of them were carved with Chinese characters. The letters were usually carved on flat and broad rocks, and they mainly had the shape of a small waterfall and a wide waterfall of under 1 meter height. 25(60.9%) of the carved letters were about moral training, and it seemed that they wanted to protect their pride under the shackle of the Japanese colonization over Korea. The styles of handwriting are Hangseo and Jeonseo except for names, and show various and complex styles. The mix composition of the carved letters of 'Yusubulbu(流水不腐)' of Choseo and the rocks of Takjok(濯足) is extraordinary, and the letters carved as the shape of Nakkwan(落款) have artistic value and degree of finishing. It seemed that intellectuals during the Japanese colonization over Korea in the 1930s considered Mt. Sangduasa highly valuable region because they expressed their hope and wish for the new world on the rocks. The letters on the rocks of Mt. Sangdu are invaluable cultural landscaping elements for the improvement of landscaping symbolism of Mt. Sangdu because of colliding values and spirits of the time of 'the anguish and pain of intellectuals' and 'the status of living joyfully outside of the mundane world.'

Recent Advancement in the Stem Cell Biology (Stem Cell Biology, 최근의 진보)

  • Harn, Chang-Yawl
    • Journal of Plant Biotechnology
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    • v.33 no.3
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    • pp.195-207
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    • 2006
  • Stem cells are the primordial, initial cells which usually divide asymmetrically giving rise to on the one hand self-renewals and on the other hand progenitor cells with potential for differentiation. Zygote (fertilized egg), with totipotency, deserves the top-ranking stem cell - he totipotent stem cell (TSC). Both the ICM (inner cell mass) taken from the 6 days-old human blastocyst and ESC (embryonic stem cell) derived from the in vitro cultured ICM have slightly less potency for differentiation than the zygote, and are termed pluripotent stem cells. Stem cells in the tissues and organs of fetus, infant, and adult have highly reduced potency and committed to produce only progenitor cells for particular tissues. These tissue-specific stem cells are called multipotent stem cells. These tissue-specific/committed multipotent stem cells, when placed in altered environment other than their original niche, can yield cells characteristic of the altered environment. These findings are certainly of potential interest from the clinical, therapeutic perspective. The controversial terminology 'somatic stem cell plasticity' coined by the stem cell community seems to have been proved true. Followings are some of the recent knowledges related to the stem cell. Just as the tissues of our body have their own multipotent stem cells, cancerous tumor has undifferentiated cells known as cancer stem cell (CSC). Each time CSC cleaves, it makes two daughter cells with different fate. One is endowed with immortality, the remarkable ability to divide indefinitely, while the other progeny cell divides occasionally but lives forever. In the cancer tumor, CSC is minority being as few as 3-5% of the tumor mass but it is the culprit behind the tumor-malignancy, metastasis, and recurrence of cancer. CSC is like a master print. As long as the original exists, copies can be made and the disease can persist. If the CSC is destroyed, cancer tumor can't grow. In the decades-long cancer therapy, efforts were focused on the reducing of the bulk of cancerous growth. How cancer therapy is changing to destroy the origin of tumor, the CSC. The next generation of treatments should be to recognize and target the root cause of cancerous growth, the CSC, rather than the reducing of the bulk of tumor, Now the strategy is to find a way to identify and isolate the stem cells. The surfaces of normal as well as the cancer stem cells are studded with proteins. In leukaemia stem cell, for example, protein CD 34 is identified. In the new treatment of cancer disease it is needed to look for protein unique to the CSC. Blocking the stem cell's source of nutrients might be another effective strategy. The mystery of sternness of stem cells has begun to be deciphered. ESC can replicate indefinitely and yet retains the potential to turn into any kind of differentiated cells. Polycomb group protein such as Suz 12 repress most of the regulatory genes which, activated, are turned to be developmental genes. These protein molecules keep the ESC in an undifferentiated state. Many of the regulator genes silenced by polycomb proteins are also occupied by such ESC transcription factors as Oct 4, Sox 2, and Nanog. Both polycomb and transcription factor proteins seem to cooperate to keep the ESC in an undifferentiated state, pluripotent, and self-renewable. A normal prion protein (PrP) is found throughout the body from blood to the brain. Prion diseases such as mad cow disease (bovine spongiform encephalopathy) are caused when a normal prion protein misfolds to give rise to PrP$^{SC}$ and assault brain tissue. Why has human body kept such a deadly and enigmatic protein? Although our body has preserved the prion protein, prion diseases are of rare occurrence. Deadly prion diseases have been intensively studied, but normal prion problems are not. Very few facts on the benefit of prion proteins have been known so far. It was found that PrP was hugely expressed on the stem cell surface of bone marrow and on the cells of neural progenitor, PrP seems to have some function in cell maturation and facilitate the division of stem cells and their self-renewal. PrP also might help guide the decision of neural progenitor cell to become a neuron.