• Title/Summary/Keyword: co-cultures

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Cloning and Strong Expression of a Bacillus subtilis WL-3 Mannanase Gene in B. subtilis

  • Yoon, Ki-Hong;Lim, Byung-Lak
    • Journal of Microbiology and Biotechnology
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    • v.17 no.10
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    • pp.1688-1694
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    • 2007
  • A gene encoding the mannanase of Bacillus subtilis WL-3, which had been isolated from Korean soybean paste, was cloned into Escherichia coli and the nucleotide sequence of a 2.7-kb DNA fragment containing the mannanase gene was subsequently determined. The mannanase gene, designated manA, consisted of 1,080 nucleotides encoding a polypeptide of 360 amino acid residues. The deduced amino acid sequence was highly homologous to those of mannanases belonging to glycosyl hydrolase family 26. The manA gene was strongly expressed in B. subtilis 168 by cloning the gene downstream of a strong B. subtilis promoter of plasmid $pJ27{\Delta}88U$. In flask cultures, the production of mannanase by recombinant B. subtilis 168 reached maximum levels of 300 units/ml and 450 units/ml in LB medium and LB medium containing 0.3% locust bean gum, respectively. Based on the zymogram ofthe mannanase, it was found that the mannanase produced by recombinant B. subtilis could be maintained stably without proteolytic degradation during the culture time.

Involvement in Child Care among Korean Fathers in Multicultural Families

  • Chung, Grace H.
    • Child Studies in Asia-Pacific Contexts
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    • v.4 no.2
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    • pp.127-136
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    • 2014
  • The number of multicultural families with children are growing in South Korea. When it comes to childrearing, co-existence of two different cultures in these families pose unique challenges as husbands and wives navigate differences in norms and practices. The goal of this study was to examine what predicts involvement in child care among South Korean fathers in multicultural families. We hypothesized that the degree of wives' adaptation to South Korea and husbands' cultural characteristics, such as family ideology and cultural competence, would influence father involvement in child care. The sample consisted of 138 Korean fathers and their wives from China. Participants completed a questionnaire. Results showed that South Korean fathers engaged in a moderate level of child care activities. As hypothesized, their Chinese wives' level of adaptation to South Korea and their own cultural characteristics were significantly associated with their involvement in child care. South Korean fathers were more likely to get involved in child care when their wives were less acculturated. Also, culturally considerate and less traditional men in terms of family ideology were more likely to perform child care.

A Study on the Effect of the Mega trend on the Modern Fashion Design (현대 패션디자인에 나타난 메가 트렌드의 영향에 관한 연구)

  • Jun, Hye-Jung;Ha, Ji-Soo
    • Journal of the Korean Society of Costume
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    • v.57 no.4 s.113
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    • pp.110-125
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    • 2007
  • The purpose of this study is to analyze efforts of the mesa trends on the modern fashion design. For the study documentary research and qualitative content analysis have been carried out. Articles in magazines, seminar reports, and news related to trends were collected and analyzed to develop mega trends nowadays. As results, $2002{\sim}2006$ mega trends were extracted to Co-divergence, Emotional tech, Bi-dentity, Private+One and $2002{\sim}2006$ design trends extracted to Camouflage, Transformation, Modular system, Blur, Ease. The influences of mega trends and design trends on the modern fashion design have been proved. Those were expressed as eclectic style, deconstructionist style, reductive style and functionalist style in fashion design. The present era could be defined as cultural pluralism blended with various cultures and styles. Fashion as the essential display of contemporary culture and society has been successfully confirmed in this study.

Engineering of a Human Skin Equivalent

  • Ghalbzouri Abdoelwaheb El
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.29 no.2 s.43
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    • pp.105-130
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    • 2003
  • Human skin equivalents, also designated as cultured skin substitute (Boyce and Warden, 2002) or organotypic co-cultures (Maas-Szabowski et al., 1999, 2000, 2003), are three-dimensional systems that are engineered by seeding fibroblasts into a three-dimensional dermal matrix. Such a dermal equivalent is then subsequently seeded with human keratinocytes. After cell attachment, the culture is kept first under submerged condition to allow keratinocyte proliferation. Thereafter, the culture is lifted the air-liquid interface (A/L) to expose the epidermal compartment to the air, and to further induce keratinocyte differentiation. During the air-exposure, nutrients from the medium will diffuse through the underlying dermal substrate towards the epidermal compartment and support keratinocyte proliferation and differentiation. Under these conditions, a HSE is formed that shows high similarity with the native tissue from which it was derived (Figure 1) (Bell et at., 1981; Boyce et al., 1988; Ponec et al., 1997;El Ghalbzouri et al.., 2002).

Screening of Edible Mushrooms for the Production of Lovastatin and its HMG-CoA Reductase Inhibitory Activity (Lovastatin을 생산하는 식용버섯 선발과 HMG-CoA reductase 저해 효과)

  • Lee Jae-Won;Lee Soo-Min;Gwak Ki-Seob;Lee Ji-Yoon;Choi In-Gyu
    • Korean Journal of Microbiology
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    • v.42 no.2
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    • pp.83-88
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    • 2006
  • This research was performed to determine the production of lovastatin and its HMG-CoA reductase activity produced by fruit bodies and mycelial liquid cultures of domestic edible mushrooms (8 fungal strains). By deter-mining TLC analysis for the confirmation of the presence of lovastatin, all the extracts from fruit bodies and mycelial liquid culture showed same Rf value (0.46), whick was identical to that of the standard lovastatin. In order to extract lovastatin from fruit body, the mixture of water/acetonitrile/methanol was chosen as the most effective solvent. Extracts from fruit body and mycelial liquid culture of pleurotus ostreatus produced the high-est lovastatin 0.98 mg/g based on dry biomass, and 21.90 mg/L, respectively. In the inhibition rate of 3-hydroxy-3-methylglutaryl-CoA (HMG-CoA) reductase, the highest was obtained in P. ostreatus as 67.8% among fruit bodies, and the rates of mycelial liquid culture extracts from P. ostreatus and Laetiporus sulphureus were 37.2% and 29.1%, respectively. Unusually L. sulphureus showed high inhibition rate with low content of lovastatin due to the contribution of campesterol and gamma-sitosterol with hypocholesterolemic activity as metabolites.

Effects of Supplementation of Synbiotic Co-cultures Manufactured with Anaerobic Microbes on In Vitro Fermentation Characteristics and In Situ Degradability of Fermented TMR (혐기성 미생물로 제조한 synbiotics 혼합배양물의 첨가가 발효 TMR의 발효특성과 소실률에 미치는 영향)

  • Lee, Shin-Ja;Shin, Nyeon-Hak;Hyun, Jong-Hwan;Kang, Tae-Won;An, Jung-Jun;Jung, Ho-Sik;Moon, Yea-Hwang;Lee, Sung-Sill
    • Journal of Life Science
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    • v.19 no.11
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    • pp.1538-1546
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    • 2009
  • This study was conducted to estimate the in vitro fermentation characteristics and in situ degradabilities of total mixed rations fermented by the synbiotic co-cultures composed of various anaerobic microorganisms in the rumen of cow. Seventy two TMR bags (4 treatments $\times$ 6 fermentation days $\times$ 3 replications) were manufactured for in vitro and in situ experiments. The experiment was composed of four treatments including the control, the mould and bacteria synbiotics (T1), the mould and yeast synbiotics (T2) and the bacteria and yeast synbiotics (T3). Each treatment had six fermentation days (1, 3, 5, 7, 14, 21 day) with three replications. Two rumen cannulated Holstein cows (550 ㎏ of mean body wt) were used for in situ trial, and a total of 96 nylon bags were retrieved from the rumen according to eight fermentation times (1, 3, 6, 9, 18, 24, 48 and 72 hr). The mean fermentation temperatures of TMRs by supplementation of anaerobic micoorganism co-cultures ranged from $22.97^{\circ}C$ to $26.07^{\circ}C$, and tended to increase steadily during the entire period. pH values of the F-TMRs ranged from 4.39 to 4.98 and tended to decrease with the extension of the fermentation period, and decreased by supplementation of synbiotics (p<0.05). The ammonia concentrations of F-TMRs were not affected by addition of synbiotic co-cultures during the early fermentation period (within 7 days), but was lowest (p<0.05) in T3 during the late fermentation periods (after 14 days). Lactic acid concentration of F-TMR was lowest in T3 at 1 day of fermentation, but was not different from treatments in the other fermentation days. Microbial growth rates of F-TMR reached a peak at 7 days of fermentation, and afterward tended to decrease. In in situ experiment, the DM disappearance rates were higher in T1 than the control during early fermentation times (within 3 hours), but was vice versa at 48 hours of fermentation (p<0.05). There was no significant difference in effective DM degradability among treatments. NDF and ADF disappearance rates in situ were similar to those of DM. From the above results, the supplementation of synbiotics, particularly the mould and bacteria synbiotics, resulted in improving the pH and concentration of lactic acid of F-TMR as parameters of fermentation compare to the control, and also had higher in situ disappearance rates of DM, NDF and ADF than the control at early fermentation time. However, effective DM degradability was not affected by supplementation of synbiotics.

A Study on the Physical Properties and Cytotoxicity of Tooth Ash and Dental Procelain (치아회분(齒牙灰粉)과 도재복합(陶材複合) 매식체(埋植體)의 물리적(物理的) 성질(性質) 및 세포배양(細胞培養)에 의(依)한 조직친화성(組織親和性)에 관(關)한 연구(硏究))

  • Hoh, Ki-Young
    • The Journal of Korean Academy of Prosthodontics
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    • v.22 no.1
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    • pp.51-68
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    • 1984
  • The purpose of this study is primarily to test the use value of tooth ash as an alternative material of the synthetic hydroxyapatite. For this purpose the author performed the experimental study to investigate the phsyical properties of sintered tooth ash and its histocompatibility in vitro. The tooth ash was made by incinerating procedure at $650^{\circ}C,\;750^{\circ}C,\;850^{\circ}C,\;950^{\circ}C\;and\;1050^{\circ}C$ respectively. The composition of tooth ash was analyzed and X-ray diffraction was done. The experimental specimens were molded to the cylinderical form 1 cm high, 1 cm in diameter under the pressure of $1000kg/cm^2$, which were divided into two groups; the one is sintered tooth ash at $1100^{\circ}C$ and the other is fired mixture of tooth ash and dental porcelain mixed to the weight ratio of 4:6, 5:5, 6:4 and 7:3. The physical propoerties of the sintered specimens were examined and their microstructure was observed under the Scanning Electron Microscope. The results obtained were as followings: 1. The difference of the tooth ash composition depending on incinerating temperature was of no significance, but the $CO_2$ disappeared from $950^{\circ}C$. 2. X-ray diffraction showed the tooth ash was mainly composed of hydroxyapatite and a small amount of - white lockite. But phase transformation was not disclosed. 3. The microstructure of the sintered specimens of the ashed tooth powder was of no difference in the structure and grain size accompanying the ashed temperature, but sintering ability seemed to be the best in the specimen incinerated at $950^{\circ}C$. 4. There was good wettability in the mixed sintered specimens of the ashed tooth powder and the porcelain powder. 5. The compressive strength of the sintered specimens of the tooth ash incinerated at $950^{\circ}C$ was the highest with $589.75kg/cm^2$ and the porosity and the absorption were the lowest as well. 6. The mixed sintered specimens of the tooth ash and porcelain powder was good in the physical properties in the case of mixed weight ratio of 6:4. 7. The animal fibroblast cultures with porcelain showed increase in the cell number, whereas the tooth ash showed a small degree of growth inhibition. But the difference of cell multiplication efficiency between control cultures and test cultures with tooth ash was not observed.

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Effects of Daejo-whan on the Ischemic Damage of Cerebral Neurons in Culture (대조환이 대뇌신경세포의 허혈성 손상에 미치는 영향)

  • Park Se Hong;Lee Kwang Ro;Bai sun jun;Cheong Sang Su;Kang Sei Young;Lee Sang Kwan;Lee Sung Keun;Yoon Ji won;Sung Kang Keyng
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.17 no.6
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    • pp.1500-1508
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    • 2003
  • This study was performed to clarify the neurotoxic mechanism of nerve cells damage by brain ischemia. The cytotoxic effect of ischemia was determined by XTT assay, NR assay, superoxide dismutase(SOD) activity, amount of malondialdehyde(MDA), lactate dehydrogenase(LDH) activity, protein synthesis and tumor necrosis factor(TNF)-α activities after cerebral neurons derived from mouse were exposed to ischemia for 1∼30 minutes. In addition, the protective effect of extract of Daejo-whan(DJW) on ischemia-induced neurotoxicity was examined in these cultures. 1. Ischemia decreased cell number and viability by XTT assay or NR assay when cultured cerebral neurons were exposed to 95% N2/5% CO₂ for 1∼20 minutes in these cultures. 2. Ischemia decreased SOD and protein syntheses, but it increased amount of MDA and, LDH and TNF-α activities in these cultures. 3. In the neuroprotective effect of DJW extracts on cerebral neurons damaged by ischemia, DJW extracts increased SOD activity and protein synthesis. While, it decreased amount of MDA and, LDH and TNF-α activities after cerebral neurons preincubated with herb extracts. It suggests that brain ischemia has neurotoxicity on cultured mouse cerebral neurons, and the herb extract such as DJW was very effective in blocking the neurotoxicity induced by ischemia in cultured mouse cerebral neurons.

Effect of Osmotic Pressure on hCTLA-lg Production in Transgenic Rice Cell Suspension Cultures (형질전환된 벼세포 배양에 있어서 삼투압 조절에 따른 hCTLA4-lg 생산성 변화)

  • Choi Sung-Hun;Lee Song-Jae;Hong Seok-Mi;Cho Ji-Suk;Kim Dong-Il
    • KSBB Journal
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    • v.20 no.4
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    • pp.278-284
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    • 2005
  • An immunosuppressive agent, human cytotoxic T lymphocyte antigen 4 (hCTLA4), is used for the prevention of graft rejection and treatment of autoimmune diseases. hCTLA4-Ig, a CTLA4-immunoglobulin fusion protein, was produced and secreted from transgenic rice cell suspension cultures using rice a-amylase (RAmy3D) expression system. In this system, hCTLA4-Ig expression was regulated metabolically by sugar starvation. For the purpose of improving hCTLA4-Ig production, the effects of osmotic pressure was investigated in suspension cultures of transgenic rice cells. The highest production level was achieved at 40 mM sorbitol $(140\;mOsm{\cdot}kg^{-1}\;H_2O)$. Using the medium with 8 mM glucose, the level of hCTLA4-Ig in the medium reached 45.3 mg/L. By adjusting the osmotic pressure of induction medium, it was found that the hCTLA4-Ig production could be increased up to 2.1-fold compared with that in batch culture.