• Animal cells and systems
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• v.2 no.1
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• pp.21-26
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• 1998

Three species of Poecilosclerid sponge (class Demospongiae, subclass Ceractinomorpha) are newly described from the waters around Cheju Island Keomun Island and Keoje Island. They are Antho (Plocamia) bakusi, Clathria (clathria) koreana and Oxymycale rhoi.

• Animal cells and systems
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• v.4 no.3
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• pp.231-237
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• 2000

The effects of microgravity and hypergravity on aging are still poorly documented, particularly in mammals. However, there is a growing interest for the use of the fruit fly, Drosophila melanogaster, and this species may be now considered as a model organism in gravitational biology studies dealing with aging.

• Journal of Microbiology and Biotechnology
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• v.23 no.8
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• pp.1140-1146
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• 2013

Bioelectrochemical systems (BESs) have been suggested as a new technology for wastewater treatment while accomplishing energy and chemical generation. This study describes the performance of BESs based on mixed culture that are capable of reducing carbon dioxide to acetate. The cathode potential was a critical factor that affected the performance of the BESs. The rate of acetate production increased as the electrode potential became more negative, from 0.38 mM $d^{-1}$ (-900 mV vs. Ag/AgCl) to 2.35 mM $d^{-1}$ (-1,100 mV), while the electron recovery efficiency of carbon dioxide reduction to acetate increased from 53.6% to 89.5%. The microbial population was dominated by relatives of Acetobacterium woodii when a methanogenic inhibitor was added to the BESs initially.

• Journal of the Korean Chemical Society
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• v.59 no.2
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• pp.188-193
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• 2015

• Interdisciplinary Bio Central
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• v.3 no.2
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• pp.8.1-8.6
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• 2011

Background: Thanks to the development of the mathematical/statistical reverse engineering and the high-throughput measuring biotechnology, lots of biologically meaningful genegene interaction networks have been revealed. Steady-state analysis of these systems provides an important clue to understand and to predict the systematic behaviours of the biological system. However, modeling such a complex and large-scale system is one of the challenging difficulties in systems biology. Results: We introduce a new stochastic modeling approach that can describe gene regulatory mechanisms by dividing two (DNA and protein) layers. Simple queuing system is employed to explain the DNA layer and the protein layer is modeled using G-networks which enable us to account for the post-translational protein interactions. Our method is applied to a transcription repression system and an active protein degradation system. The steady-state results suggest that the active protein degradation system is more sensitive but the transcription repression system might be more reliable than the transcription repression system. Conclusions: Our two layer stochastic model successfully describes the long-run behaviour of gene regulatory networks which consist of various mRNA/protein processes. The analytic solution of the G-networks enables us to extend our model to a large-scale system. A more reliable modeling approach could be achieved by cooperating with a real experimental study in synthetic biology.

• Journal of the Korean Society of Combustion
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• v.8 no.1
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• pp.46-56
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• 2003

The present paper is concerned with the development of the computational biology in the past half century and its relationship with combustion. The modem computational biology is considered to be initiated by the work of Alan Turing on the morphogenesis in 1952. This paper first touches the life and scientific achievement of Alan Turing and his theory on the morphogenesis based on the reactive-diffusive instability, called the Turing instability. The theory of Turing instability was later extended to the nonlinear realm of the reactive-diffusive systems, which is discussed in the framework of the excitable media by using the Oregonator model. Then, combustion analogies of the Turing instability and excitable media are discussed for the cellular instability, pattern forming combustion phenomena and flame edge. Finally, the recent efforts on numerical simulations of biological systems, employing the detailed bio-chemical knietic mechanism is discussed along with the possibility of applying the numerical combustion techniques to the computational cell biology.

• Molecules and Cells
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• v.39 no.6
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• pp.439-446
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• 2016

Clearing and labeling techniques for large-scale biological tissues enable simultaneous extraction of molecular and structural information with minimal disassembly of the sample, facilitating the integration of molecular, cellular and systems biology across different scales. Recent years have witnessed an explosive increase in the number of such methods and their applications, reflecting heightened interest in organ-wide clearing and labeling across many fields of biology and medicine. In this review, we provide an overview and comparison of existing clearing and labeling techniques and discuss challenges and opportunities in the investigations of large-scale biological systems.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2003.09a
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• pp.353-357
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• 2003

Although it is more and more well accepted that modeling is a help for experimental biology, little is known about how to integrate physiological processes in general. The fact that no general theory exist in biology has big consequences, the most important being the difficulty to integrate biological phenomena. 1 will present a solution for the three dependent following issues: i) in an appropriate theoretical framework, integration consists in coupling models that each describe physiological mechanisms (formalization is a necessary condition to integration); ii) a biological theory with its own concepts leads to unifying principles in biology that are different from and complementary to physical principles; iii) such a formalized theory consists in a representation in terms of functional interactions and a specific formalism(S-Propagator). Hence a biological theory is of a topological and geometrical nature, in contrast to physical theories that are of a geometrical nature. An application to the interpretation of intelligence is proposed, based on the "intelligence"of movement.

• IMMUNE NETWORK
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• v.20 no.6
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• pp.44.1-44.19
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• 2020

The human body is continuously threatened by pathogens, and the immune system must maintain a balance between fighting infection and becoming over-activated. Mucosal surfaces cover several anatomically diverse organs throughout the body, such as the respiratory and gastrointestinal tracts, and are directly exposed to the external environment. Various pathogens invade the body through mucosal surfaces, making the mucosa the frontline of immune defense. The immune systems of various mucosal tissues display distinctive features that reflect the tissues' anatomical and functional characteristics. This review discusses the cellular components that constitute the respiratory and gastrointestinal tracts; in particular, it highlights the complex interactions between epithelial and immune cells to induce Ag-specific immune responses in the lung and gut. This information on mucosal immunity may facilitate understanding of the defense mechanisms against infectious agents that invade mucosal surfaces, such as severe acute respiratory syndrome coronavirus 2, and provide insight into effective vaccine development.

• Molecules and Cells
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• v.39 no.2
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• pp.149-155
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• 2016

In the heart, excitation-contraction (E-C) coupling is mediated by $Ca^{2+}$ release from sarcoplasmic reticulum (SR) through the interactions of proteins forming the $Ca^{2+}$ release unit (CRU). Among them, calsequestrin (CSQ) and histidine-rich $Ca^{2+}$ binding protein (HRC) are known to bind the charged luminal region of triadin (TRN) and thus directly or indirectly regulate ryanodine receptor 2 (RyR2) activity. However, the mechanisms of CSQ and HRC mediated regulation of RyR2 activity through TRN have remained unclear. We first examined the minimal KEKE motif of TRN involved in the interactions with CSQ2, HRC and RyR2 using TRN deletion mutants and in vitro binding assays. The results showed that CSQ2, HRC and RyR2 share the same KEKE motif region on the distal part of TRN (aa 202-231). Second, in vitro binding assays were conducted to examine the $Ca^{2+}$ dependence of protein-protein interactions (PPI). The results showed that TRN-HRC interaction had a bell-shaped $Ca^{2+}$ dependence, which peaked at pCa4, whereas TRN-CSQ2 or TRN-RyR2 interaction did not show such $Ca^{2+}$ dependence pattern. Third, competitive binding was conducted to examine whether CSQ2, HRC, or RyR2 affects the TRN-HRC or TRN-CSQ2 binding at pCa4. Among them, only CSQ2 or RyR2 competitively inhibited TRN-HRC binding, suggesting that HRC can confer functional refractoriness to CRU, which could be beneficial for reloading of $Ca^{2+}$ into SR at intermediate $Ca^{2+}$ concentrations.