• YAKHAK HOEJI
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• v.50 no.3
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• pp.184-190
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• 2006

We investigated the effect of fresh Rehmanniae radix methanol extracts (RGMeOH) on the in vitro production of cytokines by splenocytes and peritoneal macrophages isolated from C57BL/6 mice. Peritoneal macrophages and splenocytes were incubated with various concentrations of RGMeOH in the presence of $10\;{\mu}g/ml$ of lipopolysaccharide (LPS) $1\;{\mu}g/ml$ of concanavalin A (Con A) for cytokine assay, These results showed that RGMeOH remarkably attenuated LPS-increased production of $TNF-{\alpha}$ but not IL-6 by peritoneal macrophages and enhanced LPS-stimulated production of IL-10 in a dose-dependent manner RGMeOH significantly augmented the LPS- or Con A-stimulated production of IL-2 and $IFN-{\gamma}$ by splenocytes. These findings suggest that RGMeOH may attenuate inflammatory responses through down-regulation of $TNF-{\alpha}$ and up-regulation of IL-10, and that RGMeOH may up-regulate cell-mediated immune responses through increase in IL-2 and $IFN-{\gamma}$ production.

• Korean Journal of Food Science and Technology
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• v.52 no.6
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• pp.622-626
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• 2020

Recent studies have suggested that Canavalia gladiate, a dietary food and traditional folk medicine, has promising pharmaceutical potential, but the effects have mostly been demonstrated using its organo-soluble extract. To date, its immunomodulatory effect depending on the extraction method is unclear. Here, the immune responses of macrophages to C. gladiate and the underlying mechanisms were studied. C. gladiate hot water extract (CGW) induced cytokine production in bone marrow-derived macrophages (BMDMs) in a dose-dependent manner, whereas its ethanolic extract (CGE) did not. Immunoblotting analysis also showed that CGW activated nuclear factor (NF)-κB and mitogen-activated protein kinases (MAPKs). Moreover, an inhibitor assay revealed the involvement of NF-κB, p38, and JNK, but not ERK, in CGW-induced cytokine production. CGE inhibited lipopolysaccharide-stimulated production of pro-inflammatory cytokines and activation of NF-κB and MAPKs in BMDMs. The results suggest that C. gladiate regulates the immune responses of macrophages differently depending on the extraction method.

• Structural Engineering and Mechanics
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• v.89 no.3
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• pp.265-281
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• 2024

The sound radiation responses of multi-layer composite plates subjected to harmonic mechanical excitation in hygrothermal environment is numerically investigated. A homogenized micromechanical finite element (FE) based on the higher-order mid-plane kinematics replicating quadratic function as well as the through the thickness stretching effect together with the indirect boundary element (IBE) scheme has been first time employed. The isoparametric Lagrangian element (ten degrees of freedom per node) is used for discretization to attain the hygro-thermo-elastic natural frequencies and the modes of the plate via Hamilton's principle. The effective material properties under combined hygrothermal loading are considered via a micromechanical model. An IBE method is then implemented to attain structure-surrounding coupling and the Helmholtz wave equation is solved to compute the sound radiation responses. The effectiveness of the model is tested by converging it with the similar analytical/numerical results as well as the experimentally acquired data. The present scheme is further hold out for solving diverse numerical illustrations. The results revealed the relevance of the current higher-order FE-IBE micromechanical model in realistic estimation of hygro-thermo-acoustic responses. The geometrical parameters, volume fraction of fiber, layup, and support conditions alongside the hygrothermal load is found to have significant influence on the vibroacoustic characteristics.

• Proceedings of the Korean Society of Toxicology Conference
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• 2003.10b
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• pp.161-161
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• 2003

Different circling preference of mice is a reference of inter-individual differences in their endogenous neuroimmune circuits. I have investigated relationship between differential immune responses in mice, who have same age, gender, and genetic background, and circling behavior preference.(omitted)

• Journal of Microbiology and Biotechnology
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• v.25 no.11
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• pp.1787-1795
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• 2015

The transition from primary to secondary metabolism in antibiotic-producing Streptomyces correlates with expression of genes involved in stress responses. Consequently, regulatory pathways that regulate specific stress responses are potential targets to manipulate to increase antibiotic titers. In this study, genes encoding key proteins involved in regulation of the osmotic stress response in Streptomyces avermitilis, the industrial producer of avermectins, are investigated as targets. Disruption of either osaB_Sa, encoding a response regulator protein, or osaC_Sa, encoding a multidomain regulator of the alternative sigma factor SigB, led to increased production of both oligomycin, by up to 200%, and avermectin, by up to 37%. The mutations also conditionally affected morphological development; under osmotic stress, the mutants were unable to erect an aerial mycelium. In addition, we demonstrate the delivery of DNA into a streptomycete using biolistics. The data reveal that information on stress regulatory responses can be integrated in rational strain improvement to improve yields of bioactive secondary metabolites.

• KSBB Journal
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• v.13 no.4
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• pp.424-430
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• 1998

Immunositmulation effects of the mice fed with the cell lysate of Lactobacillus plantarum isolated from Kimchi were studied. The mice group fed with cell lysate was different from the control group on the degree of immune responses, e.g. 1) proliferation of splenocytes and Peyer's patch cells, 2) production of nitric oxide (NO) by peritoneal macrophages, 3) production of intestinal secretory lgA (slgA), 4) variation of TNF-${\alpha}$ and IL-2 concentration in blood, 5) production of specific lgG against sheep red blood cells. A general enhancement in enteric and systemic immune responses was observed with a simple oral administration of immunostimulators. With the oral feeding of L. plantarum, not only the total amount of gut secretion antibody, but also the binding capacity of antibodies to the enteric microorganisms including L. plantarum was increased. These experimental results clearly showed that the oral feeding of immunostimulators gave multifunctional effects on the mucosal and systemic immune systems of mice.

• YAKHAK HOEJI
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• v.51 no.4
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• pp.270-276
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• 2007

Silybin is known to be a major active flavonoid component isolated from Silybum marianum, a hepatoprotective medicinal plant. In this study, we examined the immunomodulatory role of silybin on T cell and macrophage-mediated immune responses. To do this, the proliferation of splenic lymphocytes and CD8+ CTLL-2 cells under mitogenic stimulation with lipopolysaccharide (LPS), concanavalin (Con) A and interleukin (IL)-2 and the production of $TNF-{\alpha}$ and NO from LPS- and $IFN-{\gamma}$-activated macrophages was evaluated under silybin treatment. The mitogenic proliferation of splenic lymphocytes induced by LPS and Con A was strongly diminished by silybin in a dose-dependent manner. Moreover, the proliferation of CD8+ CTLL-2 cells was also negatively modulated by the compound. In contrast, silybin did not strongly suppress the proliferation of normal splenocytes and T cell line Sup-T1 cells, indicating that the inhibitory effect of silybin may be due to blocking only mitogenic responses of splenic lymphocytes. In addition, silybin inhibited $TNF-{\alpha}$ production in LPS-stimulated RAW264.7 cells. Effect of silybin however was distinct, according to NO-inducing stimuli. Thus, silybin only blocked NO production induced by $IFN-{\gamma}$ but not LPS and the inhibition was increased when PMA was co-treated with $IFN-{\gamma}$. Unlike NO inhibition, however, this compound protected the cytotoxic damage of RAW264.7 cells induced by both LPS and $IFN-{\gamma}$. Therefore, our data suggest that silybin may participate in host immune responses mediated by T cells and macrophages via regulating mitogenic proliferation, and the production of $TNF-{\alpha}$ and NO, depending on cellular stimuli.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.5
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• pp.625-629
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• 2000

Six yearling Suffolk ewes were used to study the effect of different roughage proportion diets (30%=LR, and 70%=HR) and intake levels (0.7 M and 1.3 M) on heat production and thermoregulatory responses in sheep exposed to different ambient temperatures (20 and $30^{\circ}C$). Sheep fed HR had higher heat production (HP) and time spent eating (TSE) and lower time spent standing (TSS) than those fed LR. But effect of roughage proportion on vaginal temperature (Tv) was obvious only at high intake and at $30^{\circ}C$. Sheep fed high intake had higher Tv, HP, TSS, and TSE than those fed low intake. Roughage proportion and intake level did not have an effect on respiration rate (RR), but ambient temperature did. Ambient temperature did not have an effect on HP, TSS and TSE. At $30^{\circ}C$ sheep had higher Tv and RR than those at $20^{\circ}C$. There were interactions between intake level and ambient temperature in TSS, between intake level and roughage proportion in TSE, and between roughage proportion and ambient temperature in HP. Results indicate that high roughage diet imposes a greater potential heat load on animals than low roughage diet when given at high ambient temperature, but not at low ambient temperature. And the effects is more pronounced at high intake.

• Asian-Australasian Journal of Animal Sciences
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• v.8 no.6
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• pp.533-555
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• 1995

Direct-fed microbials (DFM) have been used to enhance milk production in lactating cattle and to increase feed efficiency and body weight gain in growing ruminants. Primary microorganisms that have been used as DFM for ruminants are fungal cultures including Aspergillus oryzae and Saccharomyces cerevisiae and lactic acid bacteria such as Lactobacillus or Streptococcus. Attempts have been made to determine the basic mechanisms describing beneficial effects of DFM supplements. Various modes of action for DFM have been suggested including : stimulation of ruminal microbial growth, stabilization of ruminal pH, changes in ruminal microbial fermentation pattern, increases in digestibility of nutrients ingested, greater nutrient flow to the small intestine, greater nutrient retention and alleviation of stress, however, these responses have not been observed consistently. Variations in microbial supplements, dosage level, production level and age of the animal, diet and environmental condition or various combinations of the above may partially explain the inconsistencies in response. This review summarizes production responses that have been observed under various conditions with supplemental DFM and also corresponding modification of ruminal fermentation and other changes in the gastrointestinal tract of ruminant animals.

• Korean Journal of Plant Resources
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• v.31 no.6
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• pp.597-603
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• 2018

Inhibitory effect of colchicine on growth and gravitropic responses in Arabidopsis root was explored to find whether there was an involvement of ethylene production. It has been known that cytoskeleton components are implicated in sedimentation of statoliths to respond to gravitropism and growth. The root growth was inhibited by 25% and 40% over control for 8 hr treatment of colchicine at a concentration of $10^{-5}M$ and $10^{-7}M$, respectively. The roots treated with colchicine at the concentration of $10^{-7}M$ showed the same pattern as control in 3 hr, however, gravitropic response was decreased in the next 5 hr. The colchicine treatment at the concentration of $10^{-5}M$ inhibited the gravitropic response resulting in $60^{\circ}$ of curvature. In order to better understand the role of colchicine, the production of ethylene was measured with and without the treatment of colchicine. Colchicine increased the ethylene production by 20% when compared to control via the activation of ACC oxidase and ACC synthase activity. These results suggest that the inhibition of the growth and gravitropic responses of Arabidopsis roots by the treatment of colchicine could be attributed to the rearrangement of microtubule, and increase of ethylene production.