• 제목/요약/키워드: Biological information

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Maintenance of cellular tetrahydrobiopterin homeostasis

  • Kim, Hye-Lim;Park, Young-Shik
    • BMB Reports
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    • 제43권9호
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    • pp.584-592
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    • 2010
  • Tetrahydrobiopterin (BH4) is a multifunctional cofactor of aromatic amino acid hydroxylases and nitric oxide synthase (NOS) as well as an intracellular antioxidant in animals. Through regulation of NOS activity BH4 plays a pivotal role not only in a variety of normal cellular functions but also in the pathogenesis of cardiovascular and neurodegenerative diseases, which develop under oxidative stress conditions. It appears that a balanced interplay between BH4 and NOS is crucial for cellular fate. If cellular BH4 homeostasis maintained by BH4 synthesis and regeneration fails to cope with increased oxidative stress, NOS is uncoupled to generate superoxide rather than NO and, in turn, exacerbates impaired BH4 homeostasis, thereby leading to cell death. The fundamental biochemical events involved in the BH4-NOS interplay are essentially the same, as revealed in mammalian endothelial, cardiac, and neuronal cells. This review summarizes information on the cellular BH4 homeostasis in mammals, focusing on its regulation under normal and oxidative stress conditions.

인공면역망에 의한 자율이동로봇의 행동 선택 (Action Selections for an Autonomous Mobile Robot by Artificial Immune Network)

  • 한상현;윤중선
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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    • pp.532-532
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    • 2000
  • Conventional artificial intelligence systems are not properly responding under dynamically changing environments. To overcome this problem, reactive planning systems implementing new Al principles, called behavior-based Al or emergent computation, have been proposed and confirmed their usefulness. As another alternative, biological information processing systems may provide many feasible ideas to these problems. Immune system, among these systems, plays important roles to maintain its own system against dynamically changing environments. Therefore, immune system would provide a new paradigm suitable for dynamic problem dealing with unknown environments. In this paper, a new approach to behavior-based Al by paying attention to biological immune system is investigated. The feasibility of this method is confirmed by applying to behavior control of an autonomous mobile robot in cluttered environment.

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Estimation of Relative Potency with the Parallel-Line Model

  • Lee, Tae-Won
    • 응용통계연구
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    • 제25권4호
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    • pp.633-640
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    • 2012
  • Biological methods are described for the assay of certain substances and preparations whose potency cannot be adequately assured by chemical or physical analysis. The principle applied through these assays is of a comparison with a standard preparation to determine how much of the examined substance produces the same biological effects as a given quantity (the Unit) of the standard preparation. In these dilution assays, to estimate the relative potencies of the unknown preparations to the standard preparations, it is necessary to compare dose-response relationships of standard and unknown preparations. The dose-response relationship in the dilution assay is non-linear and sigmoid when a wide range of doses is applied. The parallel line model (applied to the dose region with the steepest slope) is used to estimate the relative potency. In this paper, the statistical theory in the parallel line model is explained with an application to a dilution assay data. The parallel line method is implemented in a SAS program and is available at the author's homepage(http://cafe.daum.net/go.analysis).

Isolation of a Pestalotiopsis Species Degrading Mucilage from Fruit of Opuntia ficus-indica var. Saboten

  • Huh, Yoon-Hee;Ko, Young-Hwan
    • Journal of Applied Biological Chemistry
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    • 제50권4호
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    • pp.221-226
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    • 2007
  • The high molecular-weight mucilage extracted and purified from cactus fruit of Opuntia ficus-indica var. Saboten was degraded by the cell-free culture filtrate of a fungus isolated from soil. TLC analysis of the polymeric mucilage after incubation with the fungal culture filtrate confirmed its degradation. When the degradation products were tested for their qualitative reactions with ninhydrin and phenol-sulfuric acid, only phenol-sulfuric acid gave positive development, and ninhydrin did not show any observable color reaction. This coloring reaction suggested the presence of a carbohydrate without an amino group within the mucilage. Analyses by HPLC and liquid gel permeation chromatography on sephadex G-100 also provided additional information on degradation of the mucilage by the fungal culture filtrate. The sequences of ITS-5.8S rDNA from the fungal isolate that was cultivated for the preparation of mucilage-degrading enzyme showed 99% similarity to those of Pestalotiopsis aquatica.

Transgenic plants with cyanobacterial genes

  • Park, Youn-Il;Choi, Sang-Bong;Liu, Jang R.
    • Plant Biotechnology Reports
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    • 제3권4호
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    • pp.267-275
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    • 2009
  • Over the years, cyanobacteria have been regarded as ideal model systems for studying fundamental biochemical processes like oxygenic photosynthesis and carbon and nitrogen assimilation. Additionally, they have been used as human foods, sources for vitamins, proteins, fine chemicals, and bioactive compounds. Aiming to increase plant productivity as well as nutritional values, cyanobacterial genes involved in carbon metabolism, fatty acid biosynthesis, and pigment biosynthesis have been intensively exploited as alternatives to homologous gene sources. In this short review, transgenic plants with cyanobacterial genes generated over the last two decades are examined, and the future prospects for transgenic crops using cyanobacterial genes obtained from functional genomics studies of numerous cyanobacterial genomes information are discussed.

식물의 생물학적 시스템에 대한 방사선의 상호작용 (Effect of Irradiation on the Biological System in Plants)

  • 최종일;김진규
    • Journal of Plant Biotechnology
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    • 제40권3호
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    • pp.111-124
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    • 2013
  • Research on the basic interaction of radiation with biological systems has contributed to human society through various applications in pharmaceutical, medicine, agriculture and other technological developments. In the agricultural sciences and food technology sectors, the last few decades have witnessed a large number of pertinent works regarding the utilization of radiation for evolution of superior varieties of agricultural crops of economic importance. This review presents general information about the effect of radiation on plant specificity, dose response, and benefits. There has been summarized of the effects observed after exposure and influenced by several factors including plant characteristics and radiation features. We also report on the effect of ${\gamma}$-irradiations on plants, focusing on metabolic alterations, modifications of growth and development and changes in biochemical pathways.

Integrate-and-Fire Neuron Circuit and Synaptic Device with Floating Body MOSFETs

  • Kwon, Min-Woo;Kim, Hyungjin;Park, Jungjin;Park, Byung-Gook
    • JSTS:Journal of Semiconductor Technology and Science
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    • 제14권6호
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    • pp.755-759
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    • 2014
  • We propose an integrate-and-fire neuron circuit and synaptic devices with the floating body MOSFETs. The synaptic devices consist of a floating body MOSFET to imitate biological synaptic characteristics. The synaptic learning is performed by hole accumulation. The synaptic device has short-term and long-term memory in a single silicon device. I&F neuron circuit emulate the biological neuron characteristics such as integration, threshold triggering, output generation, and refractory period, using floating body MOSFET. The neuron circuit sends feedback signal to the synaptic transistor for long-term memory.

일 도시지역 노인의 고혈압과 우울 간의 관계 (A Study on the Relationship between Hypertension and Depression among the Elderly in Urban Areas)

  • 김명희
    • Journal of Korean Biological Nursing Science
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    • 제12권3호
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    • pp.186-194
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    • 2010
  • Purpose: This study was designed to identify the correlation among perceived health status, health behavior, activities of daily living and depression among the elderly with hypertension. Methods: The subjects consisted of 238 person aged over 65 with hypertension who live in house located in BukGu Daegu city. The Data was collected through interview with questionnaire from July, to August 10, 2010. Results: There was a significant relation between perceived health status & ADL (r=.328, p=.000) and between depression & ADL (r=-.293, p=.000). There was s significant relation between depression & perceived health status (r=-.199, p=.002). The general characteristics which significantly affected depression was sex (t=2.49, p=.013), age (F=5.882, p=.001) education (F=6.550, p=.000), occupation (t=-6.990, p=.000). Conclusion: The findings of this study provide useful information for constructing an intervention program and care for the elderly with hypertension.

정신분열증의 신경 해부학 (Neuroanatomy in Schizophrenia)

  • 민성길
    • 생물정신의학
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    • 제3권1호
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    • pp.3-13
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    • 1996
  • Many studies have been conducted to search for the anatomical abnormalities in the brain which ore etiologically related with schizophrenia. Generally schizophrenia in known to be related with decreased brain tissue, hypofrontality and abnormalities in the temporal lobe including the hippocamypus, the agmygdala and the entorhinal cortex. Other areas related with the disorder ore basal ganglia, thalamus, brain stem, pons and nucleus accumbens. Abnormality in brain asymmetry is one of the new areas of interest which needs further study. The results so for ore inconsistent and it is unlikely that the abnormality in one structure is the only cause of the disorder. Rather, schizophrenia develops from the impairment of the parallel processing of integrated and reciprocal information which is distributed to the multiple structures. Histopathologic studies in the postmortem brain suggest that schizophrenia is related with neurodevelopmental abnormality rather than neurodegenerative abnormality.

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BDNF가 ADHD의 병인과 치료에 미치는 영향 (Association between the Brain-Derived Neurotropic Factor and Attention Deficit Hyperactivity Disorder)

  • 강나리;송재민;곽영숙
    • 생물정신의학
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    • 제25권2호
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    • pp.21-30
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    • 2018
  • Attention deficit hyperactivity disorder (ADHD) is a common childhood psychiatric disorder. Recently, it has been suggested that brain-derived neurotropic factor (BDNF) may play a role in the pathogenesis of ADHD. Our aim of this review is to understand the physiological functions of BDNF and its potential relationship with ADHD and therapeutic approaches of ADHD. Searches were conducted in Pubmed and Research Information Service System (RISS). In this review, we summarized important literatures for the physiological functions of BDNF in neurodevelopment, change of serum BDNF level in ADHD, association of BDNF polymorphism and ADHD and potential association of treatment of ADHD with serum BDNF level. Further studies are required to more clearly understand the source and the role of BDNF in ADHD and to develop BDNF based-ADHD treatement.

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