• Journal of Microbiology and Biotechnology
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• v.17 no.5
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• pp.712-720
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• 2007

To investigate clonal variations of recombinant Chinese hamster ovary(rCHO) clones in response to culture pH and temperature, serum-free suspension cultures of two antibody-producing CHO clones(clones A and B), which were isolated from the same parental clone by the limiting dilution method, were performed in a bioreactor at pH values in the range of 6.8-7.6, and two different temperatures, $33^{\circ}C\;and\;37^{\circ}C$. In regard to cell growth, clone A and clone B displayed similar responses to temperature, although their degree of response differed. In contrast, clones A and B displayed different responses to temperature in regard to antibody production. In the case of clone A, no significant increase in maximum antibody concentration was achieved by lowering the culture temperature. The maximum antibody concentration obtained at $33^{\circ}C$(pH 7.4) and $37^{\circ}C$(pH 7.0) were $82.0{\pm}2.6$ and $73.2{\pm}4.1{\mu}g/ml$, respectively. On the other hand, in the case of clone B, an approximately 2.5-fold increase in maximum antibody concentration was achieved by lowering the culture temperature. The enhanced maximum antibody concentration of clone B at $33^{\circ}C$($132.6{\pm}14.9{\mu}g/ml$ at pH 7.2) was due to not only enhanced specific antibody productivity but also to prolonged culture longevity. At $33^{\circ}C$, the culture longevity of clone A also improved, but not as much as that of clone B. Taken together, CHO clones derived from the same parental clone displayed quite different responses to culture temperature and pH with regards antibody production, suggesting that environmental parameters such as temperature and pH should be optimized for each CHO clone.

• Proceedings of the KSAR Conference
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• 2001.03a
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• pp.13-13
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• 2001

This study was undertaken to evaluate the effects of catalase using xanthine (X) - xanthine oxidase (XO) system on in vitro maturation and fertilization in pig. When follicular oocytes were cultured in maturation medium with X and/or XO, the maturation rates were not significantly different between in medium with and without catalase despite of different culture periods. However, significantly (P<0.05) higher maturation rates were obrained in culture with X-XO system. The rates of degenerated oocytes were increased with culture periods prolonged, and were significantly (P<0.05) higher in medium without than with catalase at 120 h of culture. On the other hand, the parthenogenetic oocytes were observed with high proportions at 72 h of culture, hut were not different in medium with and without catalase at various times of culture. In another experiment, the frozen-thawed boar spermatozoa treated with X-XO system for in vitro fertilization. The penetration rates were higher in medium with that than without catalase during the in vitro fertilization with, none (P<0.05), XO and X＋XO. On the other hand, when sperm were treated with none, X, XO and X＋XO, lipid peroxidation were higher in medium without that than with catalase. However, the changes in sperm penetration and lipid peroxidation showed opposite patterns. The sperm suspensions were also treated with X and/or XO for assay of sulfhydryl (-SH) group content. Under the above all conditions, sperm-SH group were higher detected In medium with that than without catalase. The activity of sperm binding to zona pellucida was also evaluated through binding to salt-stored porcine oocytes. In control group, sperm binding to zona pellucida were higher than in medium with X, XO and X＋XO groups. No significant differences, however, were observed between medium with and without catalase. In conclusion, the exposure of follicular oocytes and spermatozoa to X-XO system may be caused stimulating in vitro maturation and fertilization in pig. This work was supported by grant No. 2000-1-22200-001-3 from the Basic Research Program of the Korea Science & Engineering Foundation.

• Biomolecules & Therapeutics
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• v.2 no.3
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• pp.236-243
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• 1994

A splenocyte culture system supplemented with liver microsomes was developed to detect immunotoxic chemicals which require metabolic activation using cyclophosphamide as a positive standard. When liver microsomes were added to splenocyte cultures isolated from female B6C3Fl mice, the proliferation of splenocytes by lipopolysaccharide (LPS) was increased and the proliferation by concanavalin A (Con A) was decreased. However, when compared with each corresponding control, cyclophophamide was successfully activated to metabolites capable of suppressing Iymphoproliferative responses. This suppression was clearly dependent upon the amounts of microsomes added and/or the concentration of cyclophosphamide exposed. In these cultures, the proliferation of splenocytes was suppressed when the cells were exposed to cyclophosphamide on the day of culture initiation. On the other hand, microsome was responsible for the increase in LPS mitogenicity and NADPH was responsible for the decrease in Con A mitogenicity. Finally, our present culture system was compared with the hepatocyte-splenocyte coculture system which we had developed earlier. We found that the hepatocyte-splenocyte coculture was better able to activate cyclophosphamide to metabolites capable of suppressing the antibody response to sheep erythrocytes. Although our present culture system was relatively poor to activate cyclophosphamide in cultures for antibody response, it will be useful as a simple screening method to detect suppression of certain in vitro immunotoxic parameters like LPS mitogenicity by chemicals which require metabolism.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.21 no.2
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• pp.141-146
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• 2018

Nowadays, Klebsiella oxytoca is described as a causative organism for antibiotic-associated hemorrhagic colitis (AAHC). Here we report two cases of pediatric AAHC, from which K. oxytoca was cultured after starting amoxicillin-clavulanate or amoxicillin treatment. The patients developed severe abdominal pain and a large amount of bloody diarrhea. K. oxytoca was obtained in intestinal fluid culture of a boy through the colonoscopy. On the other hand, colonic tissue culture and intestinal fluid culture were negative of the other patient. K. oxytoca was detected in stool culture when he was admitted. These cases showed characteristic endoscopic findings of segmental hemorrhagic colitis, and both boys recovered spontaneously within 2-3 days after they stopped taking the antibiotics. Therefore, in children who develop relatively large amount of bloody diarrhea after antibiotic treatment, we should consider AAHC caused by K. oxytoca.

• Clinical and Experimental Reproductive Medicine
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• v.39 no.3
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• pp.95-106
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• 2012

It has been revealed that multiple cohorts of tertiary follicles develop during some animal estrous cycle and the human menstrual cycle. To reach developmental competence, oocytes need the support of somatic cells. During embryogenesis, the primordial germ cells appear, travel to the gonadal rudiments, and form follicles. The female germ cells develop within the somatic cells of the ovary, granulosa cells, and theca cells. How the oocyte and follicle cells support each other has been seriously studied. The latest technologies in genes and proteins and genetic engineering have allowed us to collect a great deal of information about folliculogenesis. For example, a few web pages (http://www.ncbi.nlm. nih.gov; http://mrg.genetics.washington.edu) provide access to databases of genomes, sequences of transcriptomes, and various tools for analyzing and discovering genes important in ovarian development. Formation of the antrum (tertiary follicle) is the final phase of folliculogenesis and the transition from intraovarian to extraovian regulation. This final step coordinates with the hypothalamic-pituitary-ovarian axis. On the other hand, currently, follicle physiology is under intense investigation, as little is known about how to overcome women's ovarian problems or how to develop competent oocytes from in vitro follicle culture or transplantation. In this review, some of the known roles of hormones and some of the genes involved in tertiary follicle growth and the general characteristics of tertiary follicles are summarized. In addition, in vitro culture of tertiary follicles is also discussed as a study model and an assisted reproductive technology model.

• Journal of Microbiology and Biotechnology
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• v.2 no.3
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• pp.209-214
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• 1992

Serratia marcescens co-cultured with various phytopathogenic fungi, including Rhizopus stolonifer, Helminthosporium allii, Pyricularia oryzae, Fusarium oxysporium and Collectothricom cassiicola, in an LB- agar medium containing 1.5% swollen chitin, significantly inhibitied fungal growth. Fungal hyphae grew rapidly outward from the culture dish center, but the hyphal extensions of the pathogenic fungi were significantly inhibited in a perimetric contact area with S. marcescens. This was especially evident in pathogenic fungi which have a high chitin content in their cell walls. The extracellular chitinase activities of S. marcescens were increased seven fold by the addition of 1.5% swollen chitin to the LB-broth, compared to chitinase activities in a culture medium without chitin. The type of induction was dependent on the various forms of chitin used. When the culture supernatant of S. marcescens or the chitinases of Streptomyces griceus purchased from Sigma Chemical Co., were incubated with the mycelium of F. oxysporium, the mycelium gradually burst as cultivation time progressed and completely lysed after incubation for 2 days. On the other hand, E. coli extract did not hydrolyze the F. oxysporium mycelium at all. These data showed that the chitinolytic activities of S. marcescens play important roles in the biochemical control of phytopathogenic fungi.

• Journal of Korean Society of Rural Planning
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• v.19 no.1
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• pp.165-177
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• 2013

This study deals with rural village development project of Gasangri, Yeongcheon city area, based on the use of the cultural factors and strengthening them in study area. Unlike other cases of today's Korean rural village development projects, this plan keenly concerns not only for tourists but also for the village people. Since culture means the quality of life also, this project especially deals with 'community', 'well-being', and 'convenience' for the inhabitants. On the other hand, it attempts to connect with "Cyan Museum", which is the first grade art gallery remodelled from closed school, to make village of culturally abundant atmosphere. In result, seven sub-projects of the expansion of basic living foundation, and two improvement of landscape in area have planned. Among stereotype of rural development projects and similar programs of tourism, the project makes difference on targeting for the meaning and resource of place culture.

• Journal of Family Resource Management and Policy Review
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• v.13 no.2
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• pp.153-167
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• 2009

This research analyzes factors of family life adjustment in mixed-culture families through a focus group and individual interviews with nine mixed-culture couples eighteen people who live in city C. First, the reason that women of other cultures wants to marry Korean men is because they find it a good opportunity, as they expect that Korean husbands will take responsibility of their family. On the other hand, Korean men also expect that they would have some similarities to each other. Also, in southeastern Asian men have more freedom than women to choose an international marriage in Southeastern Asia. Second, mixed-culture couples in everyday life are affected by communication problems, cultural differences, natural environment, financial situation, male -dominant attitude, self-adjustment pressure, house-work role and financial support from their own country. Third, wives from other cultures ask for social support to adjust in Korea and make a healthy family. These women can be important, as they have their own role in the family even though they may be far from their mother in law's strong expectation in how well she can adopt Korean culture.

• Clinical and Experimental Reproductive Medicine
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• v.23 no.3
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• pp.293-301
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• 1996

In the present study, mouse follicular oocytes and 2-cell embryos(late -zygote stage embryos included) were cultured on the electric pad for electric stimulation in the culture incubator. In addition, follicular oocytes and embryos were tested for maturation and development under higher temperature condition($39^{\circ}C$).Mouse follicular oocyte maturation were not affected by anion electric stimulation and there is no significant difference in GBVD and MI between the control and experiment group after 4hr culture. In the embryo culture, it was found that more morula and blastocyst were found in the electric stimulation group rather than the control(96hr). This may seem to be caused with cytoplasmic $Ca^{2+}$ transient rise by electric stimulation(anion pad). On the other hand higher temperature incubation ($39^{\circ}C$) on the anion pad caused all the embryos degenerated within $12h{\sim}24hr$ culture. This was quite different from large animal embryos(bovine, pig, sheep), in which beneficial effect of high temperature incubation for oocyte maturation and embryo development were found.

• Journal of the Speleological Society of Korea
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• no.92
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• pp.19-30
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• 2009

The purpose of this paper work is to establish the plans of Gyeongju' identity through the activation of various culture tourism which for literature, narrative, experience and others in company with history tourism. And so first of all we are examined thoroughly the literature related to the characteristics of urban identity and the spot marketing in our country for establishing of this work. And then also we are carried out survey about the cases of Pyeongchang-gun where built around Hyo-seok Lee and Namwon where is too well known the tale of Chunhyang and then make surveyed the actual locale on Gongju and Buyeo in which the old capital of Baekjae. On the other hand the paper work are suggested the plans that Gyeongju' identity has been settled such as the historic culture tourism city of the various culture tourism programs by using of SWOT analysis.