• Archives of Pharmacal Research
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• 제14권2호
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• pp.147-159
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• 1991

Effects of twenty-one different flavonoids and their related compounds on the phagocytosis of colloidal carbon by macrophages in liver and spleen humoral immune responses against bacterial $\alpha$-amylase and cellular immune responses against oxazolone and dinitrofluorobenzene were studied in vivo and in vitro. It was shown that most of the flavonoids accelerated significantly the phagocytosis, and they suppressed significantly not only humoral and cellular immune responses but also the development of immunological memory after the antigenic stimulation. Especially, malvin was the most active in phagocysis, and disodium cromoglycate and morin were the most active in humoral and cellular immunosuppression, respectively. Daidzuin had the most potent inhibitory activity in the development of memory cells. The structure-activity relationships of the flavonoids in immunosuppression became apparant from these results: 1. The presence of $C_{2-3}$ double bond and $C_4$ Ketone group in C-ring was important for their immunosuppressive activity. 2. Flavonoids with benzene ring at 2 or 3 position in C-ring showed the almost same activities. 3. The opening of C-ring did not affect their immunosuppressive activity. 4. The glycosylated flavonoids at 3 position in C-ring were less less potent than their aglycones. 5. Di-or tri-hydroxylated flavonoids in B-ring were more potent than mono-hydroxylated. 6. Chromanochromanone also had the immunosuppressive activity.

• 대한치과보철학회지
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• 제42권3호
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• pp.307-326
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• 2004

Statement of problem. The long-term success of implants is the development of a stable direct connection between bone and implant surface, which must be structural and functional. To improve a direct implant fixation to the bone, various strategies have been developed focusing on the surface of materials. Among them, altering the surface properties can modify cellular responses such as cell adhesion, cell motility and bone deposition. Purpose. This study was to evaluate the cellular behaviors on the surface-modified titanium by morphological observation, cellular proliferation and differentiation. Material and methods. Specimens were divided into five groups, depending on their surface treatment: electropolishing(EP) anoclizing(AN), machining(MA), blasting with hydroxyapatite particle(RBM) and electrical discharge machining(EDM). Physicochemical properties and microstructures of the specimens were examined and the responses of osteoblast-like cells were investigated. The microtopography of specimens was observed by scanning electron microscopy(SEM). Surface roughness was measured by a three-dimensional roughness measuring system. The microstructure was analyzed by X-ray diffractometer(XRD) and scanning auger electron microscopy(AES). To evaluate cellular responses to modified titanium surfaces, osteoblasts isolated from neonatal rat were cultured. The cellular morphology and total protein amounts of osteoblast-like cell were taken as the marker for cellular proliferation, while the expression of alkaline phosphatase was used as the early differentiation marker for osteoblast. In addition, the type I collagen production was determined to be a reliable indicator of bone matrix synthesis. Results. 1. Each prepared specimen showed specific microtopography at SEM examination. The RBM group had a rough and irregular pattern with reticulated appearance. The EDM-treated surface had evident cracks and was heterogeneous consisting of broad sheet or plate with smooth edges and clusters of small grains, deep pores or craters. 2. Surface roughness values were, from the lowest to the highest, electropolished group, anodized group, machined group, RBM group and EDM group. 3. All groups showed amorphous structures. Especially anodized group was found to have increased surface oxide thickness and EDM group had titaniumcarbide(TiC) structure. 4. Cells on electropolished, anodized and machined surfaces developed flattened cell shape and cells on RBM appeared spherical and EDM showed both. After 14 days, the cells cultured from all groups were formed to be confluent and exhibited multilayer proliferation, often overlapped or stratified. 5. Total protein amounts were formed to be quite similar among all the group at 48 hours. At 14 days, the electropolished group and the anodized group induced more total protein amount than the RBM group(P<.05). 6. There was no significant difference among five groups for alkaline phosphatase(ALP) activity at 48 hours. The AN group showed significantly higher ALP activity than any other groups at 14 days(P<.05). 7. All the groups showed similar collagen synthesis except the EDM group. The amount of collagen on the electropolished and anodized surfaces were higher than that on the EDM surface(P<.05).

• Molecules and Cells
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• 제39권3호
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• pp.179-185
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• 2016

Posttranscriptional regulation of RNA metabolism, including RNA processing, intron splicing, editing, RNA export, and decay, is increasingly regarded as an essential step for fine-tuning the regulation of gene expression in eukaryotes. RNA-binding proteins (RBPs) are central regulatory factors controlling posttranscriptional RNA metabolism during plant growth, development, and stress responses. Although functional roles of diverse RBPs in living organisms have been determined during the last decades, our understanding of the functional roles of RBPs in plants is lagging far behind our understanding of those in other organisms, including animals, bacteria, and viruses. However, recent functional analysis of multiple RBP family members involved in plant RNA metabolism and elucidation of the mechanistic roles of RBPs shed light on the cellular roles of diverse RBPs in growth, development, and stress responses of plants. In this review, we will discuss recent studies demonstrating the emerging roles of multiple RBP family members that play essential roles in RNA metabolism during plant growth, development, and stress responses.

• 한국산학기술학회논문지
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• 제12권6호
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• pp.2463-2469
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• 2011

이동전화기의 낙하 충격 시 디스플레이 모듈의 파손은 이동전화기의 재료, 강성 및 형상에 의하여 많은 영향을 받는다. 이동전화기 개발의 초기 단계에서는, 디스플레이 모듈의 내구성을 판단하기 위하여 모듈을 지그에 장착하여 낙하시험을 수행한다. 본 연구에서는 OLED 모듈의 충격 시험을 수행하기 위한 지그를 개발하였다. 지그의 재료, 두께 및 리브의 개수와 방향 등을 설계변수로 고려하여 실제 이동전화기가 낙하할 때 OLED 모듈이 받는 충격 응력과 가장 유사한 응력이 발생하도록 지그를 개발하였다. ABAQUS/Explicit를 사용한 1.5m 높이 충격 해석에서, 개발된 지그에 장착된 OLED 모듈의 유리에서 발생하는 최대주응력은 이동전화기에 장착된 동일 모듈의 유리에서 발생하는 최대주응력과 유사함을 확인할 수 있었다.

• IMMUNE NETWORK
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• 제9권6호
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• pp.265-273
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• 2009

Foot-and-mouth disease virus (FMDV) is a small single-stranded RNA virus which belongs to the family Picornaviridae, genus Apthovirus. It is a principal cause of FMD which is highly contagious in livestock. In a wild type virus infection, infected animals usually elicit antibodies against structural and non-structural protein of FMDV. A structural protein, VP1, is involved in neutralization of virus particle, and has both B and T cell epitopes. A RNA-dependent RNA polymerase, 3D, is highly conserved among other serotypes and strongly immunogenic, therefore, we selected VP1 and 3D as vaccine targets. VP1 and 3D genes were codon-optimized to enhance protein expression level and cloned into mammalian expression vector. To produce recombinant protein, VP1 and 3D genes were also cloned into pET vector. The VP1 and 3D DNA or proteins were co-immunized into 5 weeks old BALB/C mice. Antigen-specific serum antibody (Ab) responses were detected by Ab ELISA. Cellular immune response against VP1 and 3D was confirmed by ELISpot assay. The results showed that all DNA- and protein-immunized groups induced cellular immune responses, suggesting that both DNA and recombinant protein vaccine administration efficiently induced Ag-specific humoral and cellular immune responses.

• Journal of Microbiology
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• 제40권1호
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• pp.38-42
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• 2002

The strain KKI isolated from soil contaminated with polycyclic aromatic hydrocarbons was identified as Pseundomonas sp. based on analyses by MIDI and Biolog Identification System. Cellular and physiological responses of strain KKI to two-ring polycyclic aromatic hydrocarbon, naphthalene were evaluated using radiorespirometry, PLFAs and sequence analysis of Rieske-type iron sulfur center of dioxygenase. KKI was found to be able to rapidly mineralize naphthalene. Notably, KKI cells pregrown on phenanthrene were able to mineralize naphthalene much more rapidly than naphthalenepregrown cells. The total cellular fatty acids of KKI were comprised of eleven C-even and two C-odd fatty acids (fatty acids < 0.2% in abundance were not considered in this calculation). Lipids 12:0 2OH, 12:03 OH, 16:0, 18:1 6c, 18:0 increased for naphthalene-exposed cells, while lipids 18:1 7c1/15:0 ism 2OH, 17:0 cyclo, 18:1 7c, 19:0 cyclo decreased. Data from Northern hybridization using a naphthalene dixoygenase gene fragment cloned out from KKI as a probe provided the information that naphthalene dioxygenase gene was more highly expressed in cells grown on phenanthrene than naphthalene.

• Environmental Analysis Health and Toxicology
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• 제4권1_2호
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• pp.1-10
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• 1989

Experiments were performed on mice to investigate the influences of doxycycine and ethanol on the immune responses. Doxycycline was injected intraperitoneally and ethanol was administered in the drinking water. Mice were sensitized and challenged with sheep red blood cells. Immune responses were evaluated by humoral immunity, cellular immunity, peripheral circulating white blood cell and phagocyte activity. Pathotoxicological influences were measured by serum protein and albumin. The weight of spleen, thymus and liver were measured. Doxycline and ethanol combined administration decreased the weight of thymus and spleen. Humoral and cellular immune response were reduced by doxycycline administration. Especially ethanol combined administration significantly reduced humoral and cellular immune response. Phagocyte activity was increased by ethanol combined administration and peripheral circulating white blood cell was significantly increased by ethanol adminstration. Ethanol combined administration decreased serum A/G ratio.

• Biomolecules & Therapeutics
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• 제19권4호
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• pp.390-397
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• 2011

G protein-coupled receptor kinases (GRKs) and ${\beta}$-arrestins have been known as regulators of G protein-coupled receptors. However, it has been recently reported that GRKs and ${\beta}$-arrestins mediate receptor-mediated cellular responses in a G proteinin-dependent manner. In this scheme, GRKs work as a mediator or a scaffold protein. Among 7 members of the GRK family (GRK1-GRK7), GRK2 is the most extensively studied in vitro and in vivo. GRK2 is involved in cellular migration, insulin signaling, and cardiovascular disease. GRK6 in concert with ${\beta}$-arrestin 2 mediates chemoattractant-stimulated chemotaxis of T and B lymphocytes. GRK5 shuttles between the cytosol and nucleus, and regulates the activities of transcription factors. GRK3 and GRK4 do not seem to have striking effects on cellular responses other than receptor regulation. GRK1 and GRK7 play specific roles in regulation of rhodopsin function. In this review, these newly discovered functions of GRKs are briefly described.

• Molecules and Cells
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• 제40권2호
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• pp.83-89
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• 2017

Error-free replication and repair of DNA are pivotal to organisms for faithful transmission of their genetic information. Cells orchestrate complex signaling networks that sense and resolve DNA damage. Post-translational protein modifications by ubiquitin and ubiquitin-like proteins, including SUMO and NEDD8, are critically involved in DNA damage response (DDR) and DNA damage tolerance (DDT). The expression of interferon-stimulated gene 15 (ISG15), the first identified ubiquitin-like protein, has recently been shown to be induced under various DNA damage conditions, such as exposure to UV, camptothecin, and doxorubicin. Here we overview the recent findings on the role of ISG15 and its conjugation to target proteins (e.g., p53,$ {\Delta}Np63{\alpha}$, and PCNA) in the control of cellular responses to genotoxic stress, such as the inhibition of cell growth and tumorigenesis.

• Journal of Periodontal and Implant Science
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• 제32권4호
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• pp.827-836
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• 2002

The present study was performed to evaluate how cellular and humoral immune responses were perturbed by immunization of mixed periodontal bacterial biofilms. Each group of mice was immunizared with 1) Poqhyromonas gingivalis (P. gingivaliis) grown as a planktonic culture, 2) Fusobacterium nucleatum (F. nucleatum), 3) P. gingivalis grown as a biofilm, or 4) mixed P. gingivalis plus F. nucleatum grown as a biofilm culture, respectively. Immune mouse sera were collected from each mouse. Spleens were harvested to isolate T cells and consequently stimulated with antigen presenting cells and P. gingivalis whole cell antigen to establish P. gingivalis-specific T cell lines. There were no significant differences in the mean anti- gingivalis IgG antibody titers among mouse groups. Immunization of mice with pure P. gingivalis biofilm or mixed P gingivalis plus F. nucleatum biofilm resulted in significant reduction o f antibody avidity and opsonophagocytois function. INF-$\gamma$production by P. gingivalis-specific T cell lines was also substantially recluced in mouse groups immunized with the biofilm. It was concluded that P. gingivalis biofilm perturbs the cellular and humoral immune responses in periodontal disease.