• Fisheries and Aquatic Sciences
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• v.1 no.1
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• pp.24-29
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• 1998

Effect of extracellular calcium in vitellogenin (VTG) production in response to estradiol-17 $\beta$ $(E_2,\;2\times10^{-6}M)$ was examined in primary hepatocyte culture of rainbow trout, Onchorhynchus mykiss. Total calcium in estrogenized sera significantly increased, compared with the control, while diffusible calcium was insignificant. However, diffusible calcium in the incubation medium with $E_2$ was significantly reduced, compared with the control. The uptake of extracellular calcium by cultured hepatocytes signifIcantly increased 90 min after $E_2$ addition. Moreover, the accumulation of intracellular calcium increased in the cultures with $E_2$, regardless of the calcium concentrations in the incubation media. In addition, $E_2-primed $ VTG production was significantly decreased by withdrawal of E_2$ from the incubation medium. Moreover, VTG production by $E_2-primed$ hepatocytes was reduced by removing calcium from the incubation medium with or without $E_2$. These results suggest that the entry of extracellular calcium into the cytoplasm is an important step for VTG production in primary hepatocyte cultures in rainbow trout.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2003.11a
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• pp.159-164
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• 2003

Effects of Al on vitellogenin (VTG) and VTG mRNA induction by estradiol-17 $\beta$($E_2$) were examined in primary hepatocyte culture of rainbow trout. Hepatocytes were precultured for 2 days and then E2 ($2{\times}10^{-6}$M) and Al ($10^{-6}-10^{-4}$M) were simultaneously added to the incubation medium. Hepatocytes were cultured for 5 more days. Media and hepatocytes were then analyzed by SDS-PAGE and Northern blotting for VTG and VTG mRNA, respectively. These metal had no appreciable effect on the viability of hepatocytes in culture. However, Al interfered with VTG production and VTG mRNA expression. Al reduced VTG production in a concentration-dependent way and a significant reduction accurred at Al concentrations greater than $5{\times}10^{-5}$M. VTG mRNA expression also decreased with a negative correlation with Al concentration (r＝-0.98). These results suggest that Al inhibit VTG production at the transcriptional level to reduce VTG mRNA expression.

• Journal of Aquaculture
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• v.11 no.4
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• pp.557-564
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• 1998

Vitellogenin (VTG) induction in response estradiol-17${\beta}$ ($E_2$) were electrophoretically examined in primary hepatocyte cultures in rainbow trout. The hepatocytes were maintained as monolayers on positively charged dishes for up to 7 days. The viability of hepatocytes on Day 7 in cultures decreased about 20.7% and 23.6% with and without $E_2$, respecitively. The amount of DNA per dish also decreased to 13.7% and 14.0% with and without $E_2$, respectively. There were no differences in viability and DNA content between the control and $E_2$-treated culture. Moreover, the rate of VTG to total protein concentrations reached the maxium level at the addition of $10^{-6}$ M E2, to the incubation medium. However, the higher concentration of $10^{-5}$ M $E_2$ rater depressed the level.

• Korean Journal of Heritage: History & Science
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• v.36
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• pp.87-104
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• 2003

The Chungdo-type Pottery Culture, distributed through the middle part of the Korean peninsula, is chronologically located in the very former stage of the advent of ancient states. It has two different traditions of pottery manufacturing technique which are totally different in choosing raw materials, shaping, fixing and firing. It seems that two different traditions had been selectively applied by pottery type. In order to understand this peculiar cultural aspect, the pottery typology needs to be different from those applied to cultures where pottery was made and used under the single manufacturing tradition. This study tries to find the new pottery typology which best fits for the understanding the chronology of the Chungdo-Type Pottery Culture. For this purpose, I examined existing typologies, recognized their problems, and then build a new typology. As a result, I found that the former typologies misinterpreted the relative frequencies of each pottery type as different function or region. In this article, I propose the new pottery typology as building a primary classification within each function and region, and then synthesizing all of primary classifications. This new typology eliminates the factors of function and region in understanding the chronology of the Chungdo-Type Pottery Culture, and assorts the regional distinction by comparing pottery types in each region.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.29 no.6
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• pp.909-911
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• 1996

• Journal of Microbiology and Biotechnology
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• v.18 no.6
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• pp.1115-1120
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• 2008

A novel cathepsin B inhibitor-producing bacterium was isolated from marine sediments and identified based on its 16S rDNA sequence as Pseudomonas sp. strain PB01 (Accession No. EU126129). The growth and enzyme inhibitor production were investigated under various culture conditions. A mixture of organic nitrogen source was required for the optimal production, whereas both glucose and maltose proved to be the effective carbon sources for cathepsin B inhibitor production. Other optimal culture conditions included temperature range between 25 and $28^{\circ}C$, initial medium pH of 6.6, and shaking speed of 200 rpm. Under these optimal conditions, the maximum inhibitory activity from culture broth was approximately 50% after 30 h of cultivation. Additionally, kinetic study revealed that inhibitor production paralleled with cell growth, which suggested that the inhibitor may be a primary metabolite of that bacterium.

• Journal of Microbiology and Biotechnology
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• v.11 no.2
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• pp.186-192
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• 2001

A primary culture of human fetal hepatocytes was obtained through a therapeutic abortion process at 26 weeks of gestation period. More than $10^8$ cells were seeded on a plastic plate. These hepatocytes were infected with hepatitis B virus (HBV). The HBV was purified from serum of one chronic HBV carrier. Transformed hepatocytes were subcultured in a 10% FBS-supplemented medium. The morphology of the transformed cell was epithelial-like. The cells from the first pass showed signs of early proliferation and had a latent period of more than 3 months after 6-7 passages. After the rest period, the transformed cell proliferated actively and they were subcultured every three days. Transformed hepatocytes were characterized by detection of the HBV transcript by RT-PCR. The secretion of virions from transformed cells was investigated by PCR with the cell medium. Two types of virions secreted into the culture medium were examined by using the transmission electron microscope. Another approach to study the secretion of virions in to culture medium was carried out with HBV antibody. HBsAg was detected in the culture medium of transformed cells using ELISA and Western blot analyses. These data suggested that the human fetal hepatocyte cell line has been established by infection of HBV, in which this cell line secreted viral particles into the culture medium.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.8
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• pp.1102-1107
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• 2003

The ES cell can provide a useful system for studying differentiation and development in vitro and a powerful tool for producing transgenic animalds. To investigate the culture condition of chicken embryonic stem (CES) cells which can retain their multipotentiality or totipotency, three kinds of feeder layer cells, SNL cells, primary mice embryonic fibroblasts (PMEF) cells and primary chicken embryonic fibroblasts (PCEF) cells, were used as the feeder cells in media of DMEM supplemented with leukemia inhibitory factor (LIF), basic fibroblast growth factor (bFGF) and stem cell factor (SCF) for co-culture with blastoderm cells from stage X embryos of chicken. The alkaline phosphatase (AKP) test, differentiation experiment in vitro and chimeric chicken production were carried out. The results showed that culture on feeder layer of PMEF yielded high quality CES cell colonies. The typical CES cells clone shape revealed as follows: nested aggregation (clone) with clear edge and round surface as well as close arrangement within the clone. Strong alkaline phosphatase (AKP) reactive cells were observed in the fourth passage cells. On the other hand, the fourth passage CES cells could differentiate into various cells in the absence of feeder layer cells and LIF in vitro. The third and fourth passage cells were injected into the subgerminal cavity of recipient embryos at stage X. Of 269 Hailan embryos injected with CES cells of Shouguang Chickens, 8.2% (22/269) survived to hatching, 5 feather chimeras had been produced. This suggests that an effective culture system established in this study can promote the growth of CES cells and maintain them in the state of undifferentiated and development, which lays a solid foundation for the application of CES cells and may provide an alternative tool for genetic modification of chickens.

• International Journal of Computer Science & Network Security
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• v.22 no.4
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• pp.59-66
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• 2022

Students can successfully connect with one another thanks to the introduction of Web 2.0 and the tools and technology linked with it. The fact that rising digital tools are systematically influencing the education system is not a secret. The purpose of the research article efficiently evaluates the influence of incorporation of media in the activities of the scientific library of the higher education institution. The research Methodology is the Concepts, techniques, and procedures to effectively inculcate primary and secondary data to conduct the research effortlessly. It's worth noting that in this case, quantitative primary research was provided in the form of a survey. The researchers have proposed a survey in order to successfully instil a comprehensive view on the "incorporation of media in the operations of the scientific library of higher education institutions." As a result, fifty-one higher education institution principals were asked to attend this session. This is necessary to understand that they are both well-educated and cognizant of the impact of technology innovation on schooling. As a result, the researchers were able to gain a comprehensive view of this situation thanks to this survey. The results effectively showed that most of the participants believe that social media plays a vital role in shaping up higher education and at the same time they believe that the libraries of famous educational institutions must adapt as per the new educational trend so that teachers and students both can tap into its benefit.The practical significance of the result is manoeuvred by the efficient survey analysis and at the same time, peer-reviewed journals have been employed to put forward authentic information. Therefore, efficient insight regarding this topic has been gathered by the researchers.

• East Asian Journal of Business Economics (EAJBE)
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• v.9 no.4
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• pp.57-67
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• 2021

Purpose - The corporate culture's energy is recognized to go through the company and facilitate a new balance to realize success, which means that the culture in an environment of various organizations affects the performance of its employees. The purpose of the current research is to investigate the impact of organizational culture on employee performance. Research design, data, and methodology - The current research conducted a qualitative content analysis. The primary research approach applied by qualitative content analysis is an inductive methodology, and this approach is a type of reasoning that seeks the application of logic, which later helps develop a theory that will guide the future research. Result - Research findings of the present study indicated that five solutions to the problems encountered through the execution of culture are attached to how effective the organizational culture are when workers execute. Thus, culture is realized to boost structure, because the structure of an organization elevates the behavior of the organization. Conclusion - Workers will be aware of both the negative and positive implications of executing culture in the organization. Therefore, organization managers must learn that various employees are vital people in their vicinity, and creating a culture that would make a good rapport with them is vital.