• The Korean Journal of Nuclear Medicine
• /
• v.38 no.1
• /
• pp.99-108
• /
• 2004

Purpose: The ability to noninvasively track the migration of neural progenitor cells would have significant clinical and research implications. We generated stably transfected F3 human neural progenitor cells with human sodium/iodide symporter (hNIS) for noninvasively tracking F3. In this study, the expression patterns of hNIS gene in F3-NIS were examined according to the cultured time and the epigenetic modulation. Materials and Methods: F3 human neural stem cells had been obtained from Dr. Seung U. Kim (Ajou University, Suwon, Korea). hNIS and hygromycin resistance gene were linked with IRES (Internal Ribosome Entry Site) under control of CMV promoter. This construct was transfected to F3 with Liposome. To investigate the restoration of hNIS gene expression in F3-NIS, cells were treated with demethylating agent (5-Azacytidine) and Histone deacetylase inhibitor (Trichostatin A: TSA). The expression of hNIS was measured by I-125 uptake assay and RT-PCR analysis. Results: The iodide uptake of the F3-NIS was higher 12.86 times than F3 cell line. According to the cell passage number, hNIS expression in F3-NIS gradually diminished. After treatment of 5-Azacytidine and TSA with serial doses (up to $20{\mu}M$, up to 62.5nM, respectively) for 24 hours, I-125 uptake and mRNA of hNIS in F3-NIS were increased. Conclusion: These results suggest that hNIS transfected F3 might undergo a change in its biological characters by cell passage. Therefore, the gene ex[ressopm of exogenous gene transferred human stem cell might be affected to the epigenetic modulation such as promoter methylation and Histone deacetylation and to the cell culture conditions.

• Transactions of the Korean Society of Mechanical Engineers B
• /
• v.34 no.1
• /
• pp.83-87
• /
• 2010

We present here the effect of extracellular matrix (ECM) on the proliferation and physiology of HL-1 cardiac cells. HL-1 cell is from AT-1 mouse atrial cardiomyocyte tumor lineage. HL-1 cell can be serially passaged, yet they maintain the ability to contract which is a promising character of HL-1 cell for the cell based biosensors. HL-1 cells grow up on the ECM which can affect on the attachment and growth of HL-1. In this paper, we discuss HL-1 cell-ECM interactions with three different ECMs and non-treated surface. HL-1 cells are grown for 4 days after seeding then observed their attachment. Also they were immunostained by hoechst and EthD-1 for proliferation, phalloidin for Factin, and DAPI for nuclei. Fibronectin was revealed as the proper ECM material for HL-1 cell culture. This study can provide basic information for understanding the cell-ECM interactions and growth of HL-1 cells.

• Journal of Plant Biotechnology
• /
• v.34 no.3
• /
• pp.263-269
• /
• 2007

To establish a optimum culture condition in vitro for production of seedlings in Wasabia japonica, the effects of salt strength, sucrose concentration, and $NH_4/NO_3$ ratio on the shoot growth in MS medium were investigated. The full strength of MS medium was the best condition for shoot growth, and in $1/4{\sim}1/2x$ or 2x MS medium the growth was significantly suppressed. Growth of shoots was enhanced when sucrose was added in MS medium after 2 weeks of culture, and the best result was found at 3% sucrose addition. ${NH_4}^+/{NO_3}^-$ ratio of 10:50 gave the highest biomass of shoot in the liquid culture with MS medium, and increasing the ${NH_4}^+$ ratio in the medium significantly reduced the growth of shoot.

• Current Research on Agriculture and Life Sciences
• /
• v.6
• /
• pp.75-85
• /
• 1988

The concentration of 50 mM Nacl inhibited the shoot growth of P. nigra ${\times}$ maximowiczii in viro culture. The punctured leaves have produced so many individuals on MS basal medium with cytokinin. Especially MS basal medium with BAP 0.8mg/l showed the best shoot performance in which the average number of shoots were 127.6. For selection of NaCl tolerance shoot of poplar, punctured leaves were inoculated on MS basal medium with BAP 0.8mg/l and various concentrations of NaCl(from 10 mM to 100 mM graded by 10 mM). On the medium with over 50mM of NaCl, 13.7 to 15.7 shoots were obtained. Especially on the medium with go mM and 100mM. 10.7 and 8.3 shoots, respectively. The shoots derived from control medium (non-NaCl) were depressed growth, while the selected shoots from MS with NaCl showed good growth performance on MS basal medium with 50 mM of NaCl. From this results, we suggested that the possibility of in vitro selection to tolerance for inorganic salts in forest tree species.

• Journal of Plant Biotechnology
• /
• v.38 no.4
• /
• pp.258-262
• /
• 2011

Embryogenic callus was induced from the cultures of immature embryos of Camellia japonica L. on Murashige & Skoog's (MS) solid medium supplemented with 1 mg/L 2,4-dichlorophenoxy acetic acid (2,4-D), and then the embryogenic callus was proliferated on same medium for 4 weeks over. The embryogenic callus was sub-cultured on MS basal medium without 2,4-D to produce coyledonary stage of somatic embryo. The frequency (%) of somatic embryogenesis was 25.1%, and the majority of somatic embryos formed had a abnormal morphology with cupshaped cotyledon (48.3%), one cotyledon (12.6%), three cotyledons (9.4%), four cotyledons (1.9%), whereas was only normal morphology with two cotyledon (27.5%). When the somatic embryos with normal or abnormal cotyledons transfer to MS basal medium or $\frac{1}{2}$ MS medium with/or without plant growth regulators ($GA_3$, IBA) for regeneration, the frequency (%) of two-cotyledon embryos regenerated into plantlets was higher 11.1% than one cotyledon (0.0~8.3 %), three cotyledons (0.0~5.8%), four cotyledons (0.0%), cup-shaped (0.3~4.2%). These results demonstrated that the anomalous cotyledons of somatic embryos could caused to decrease the rate of plant regeneration.

• Korean Journal of Plant Tissue Culture
• /
• v.26 no.4
• /
• pp.251-257
• /
• 1999

Adventitious buds were produced from the cultures of mature zygotic embryos of Larix leptolepis with the highest frequency of 91.7% in SH medium containing 1.0 mg/L zeatin. The most effective cytokinin combination for inducing adventitious buds was 1.0 mg/L zeatin + 1.0 mg/L thidiazuron (40.3%). The highest mean number of adventitious buds induced in 1.0 mg/L zeatin + 1.0 mg/L 2iP or 1.0 mg/L zeatin + 1.0 mg/L kinetin combined treatments. Elongation of the adventitious buds occurred the best on half strength LM salts medium, on which the buds elongated upto 27 mm. Also, the supplement of activated charcoal in medium suppressed the elongation of the adventitious buds. The highest frequency (23.3%) of rooting from elongated shoots was obtained on the medium containing 5.0 mg/L IBA and 0.2 mg/L NAA. The highest number (3.5) of roots was induced on the medium containing 5.0 mg/L IBA alone.

• Reproductive and Developmental Biology
• /
• v.31 no.3
• /
• pp.145-152
• /
• 2007

Transgenic mice were generated by microinjecting a plasmid DNA containing the SV40 (simian virus 40) large T antigen (Tag) gene fused with mouse albumin promoter/enhancer sequences into fertilized one-cell mouse embryos. Among eleven founder transgenic animals, four developed hepatocellular carcinoma, two showed kidney cancer and one developed skin and brain tumors. Three stable transgenic lines, #1-2, #1-6 and #1-11 were established. Members of the lines #1-6 and #1-11 reproducibly developed liver tumors by 8 to 10 weeks of age but did not exhibit any phenotypic changes in other tissues. Histological changes loading to liver tumor formation occurred with predictable kinetics and could be classified into three distinct stages; (a) newborn to 3 weeks of age, characterized by hyperplastic hepatocytes with reduced amounts of cytoplasm without any nuclear alterations, (b) between 4 to 8 weeks of age, characterized by diffuse liver cell dysplasia without observable tumor nodules, and (c) 9 weeks of age and thereafter, characterized by hepatocellular carcinomas in the background of extensive liver dysplasia. Metastasis to the lung from a liver carcinoma was observed in #1-11 founder animal. This transgenic mouse system displays similarities with human liver cancers in a number of aspects and provides a useful model for the study of molecular events involved in hepatocarcinogenesis.

• Korean Journal of Poultry Science
• /
• v.39 no.2
• /
• pp.113-120
• /
• 2012

Newcastle disease virus (NDV) Kr005/V strain was generated through 55 serial passages of NDV Kr005 strain in Vero cells. The Kr005/V virus yielded high infective titers of $10^{7.8}$ $TCID_{50}/mL$ in Vero cells and the infected cells showed cytopathic effects such as marked cell rounding, though less frequent syncytia. The Kr005/V virus was heat-stable and classified into the lentogenic type with a Mean Death Time (MDT) of 120h or greater while the Kr005 strain was heat-labile and velogenic (MDT of 49.6 h). Only the single amino acid substitution (T to S) was observed at position 433 of the HN protein of the Kr005/V strain, whereas no amino acid change was found in the F protein. The Kr005/V input virus correlated well (correlation coefficient $r^2$=0.97) with the Kr005 virus when ten field sera were tested by virus neutralization test. The biological properties and usefulness of Vero cell-adapted Kr005/V virus were discussed.

• Korean Journal of Microbiology
• /
• v.28 no.1
• /
• pp.55-64
• /
• 1990

Cell volume and DNA contents of the fusants were similar to those of parents. Genetic stability of the fusants was increased when they were cultured on minimal medium (MM) rather than on complete medium (CM), and the fusants were stabilized by subculturing 7 generations each 7 day on MM agar. The finally selected fusants after being cultured for 6 months on CM were stable without segregation. The fusants could also form nuclein and ascospores, and show red and pink colors by the test of TTC colorization. Assimilability and fermentability of carbon sources of the fusants were similarto those of parents. The tolerance of KCl, NaCl, sodium propionate and cycloheximide showed the traits of one strain of parents. When the fusants were cultured for 72 hr and 60 hr in the medium containing 20% glucose and sucrose, respectively, the yield of ethanol for FWKS 260 was reached to 9.6 v/v% and 9.8v/v%, respectively. The sensitive strain Kyokai 7 was found to be killed entirely after cultivation of 48 hr by the killer toxin from the fusants. The recipient S 29 and Kyokai 7 were found to have neither L nor M dsRNA plasmid. However, K 52 and fusants had both L and M dsRNA plasmid of 4.7 kb and 2.5 kb, respectively. The curants treated by heat and cycloheximide did not contain M dsRNA plasmid, but had large amounts of L dsRNA plasmid of those of killer yeasts.

• Korean Journal of Plant Resources
• /
• v.21 no.5
• /
• pp.362-367
• /
• 2008

In order to investigate the effect of plant growth regulators on effective in vitro micropropagation, apical meristems of Pulsatilla cernua var. koreana were cultured on Murashige and Skoog's (MS) medium with 2,4-D, NAA, TDZ and BA. Media containing 2,4-D and kinetin, 2,4-D and TDZ, NAA and TDZ were not effective on callus induction. However, embryogenic or organogenic callus was obtained on media containing NAA and BA. Especially, on MS medium with 0.5mg/L NAA and 1.0mg/L BA was optimal for a high frequency (62%) of shoot or shoot bud obtained from callus. Callus proliferation, shoot multiplication and elongation were significantly increased by adding 10% coconut water on MS media with 0.5mg/L NAA and 1.0mg/L BA. Repeated subculturing of in vitro grown shoots resulted in propagation rate of 12.9 shoots per explant every 30 days. Root formation from the adventitious shoots was not easily achieved. However, roots were only produced through callus on MS medium with 2.0mg/L NAA alone or 0.5mg/L NAA and 1.0mg/L BA. These roots were used materials for callus and shoot production repetitively.