• 한국분말재료학회지
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• 제6권1호
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• pp.36-41
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• 1999

The present work has attempted to investigate the dependence of Cu infiltration kinetics on in-situ structure modification of W powder skeleton in W-Cu system. In-situ structure modification of W skeleton by addition of 0.3wt%Ni-P eutectic alloy was designed to proceed during heat-up of the W compact for Cu infiltration process. It was found that the Ni-P added W skeleton underwent remarkable stucture change only during heating-up. its structure was composed of large necks of W particles above 0.5 in the ratio of neck to particle size and smooth pore channels. The infiltration experiment showed that the infiltration kinetics for the W-Ni-P followed well the linear relationship of h vs. $t^{1/2}$ the rate constant K of which was in good agreement with the theoretical value. On the other hand, in case of the pure W skeleton a lower K value by 20% than the theoretical one was obatined. Such discrepancy is discussed in terms of skeleton structure induced infiltration mechanics.

• 대한융합한의학회지
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• 제4권1호
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• pp.19-27
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• 2022

Objectives: TSepsis and subsequent acute lung injury (ALI) is a critical state of health caused by infection or endotoxins. This study was conducted to evaluate the effect of Water Extract of Aconiti Lateralis Preparata Radix (AR) on lipopolysaccharide (LPS)-induced sepsis in C57BL/6 mice. Methods: Male C57BL/6 mice were intraperitoneally injected with LPS to induce sepsis and ALI. AR was orally fed twice at 30 min and 180 min after LPS injection. At 24 h post injection, mice were sacrificed, bronchoalveolar lavage fluid (BALF) and blood was collected, and lung tissue was harvested. Hematoxylin and eosin staining was performed in lung tissues, wet/dry ratio of the lung tissue was measured, and the serum cytokine and chemokine levels were analyzed. Results: AR revoked the LPS-induced pathological changes in lung tissues, such as abnormal histological structures, immune cell infiltration and lung edema. Also, AR suppressed the neutrophil infiltration into the lung which was greatly increased by LPS injection based on the cell content of collected BALF. Serum cytokines and chemokines were measured, and AR reversed the LPS-induced increase of cytokines such as interleukin 1 beta, interleukin 6, tumor necrosis factor alpha and chemokines including C-X-C motif chemokine ligand 1 and 2. Conclusion: TAR showed a protective effect in the pathological progress of LPS-induced ALI. Especially, AR suppressed lung edema and infiltration of neutrophils by inhibiting cytokine and chemokine expressions. Such results demonstrate the potential of AR as a therapeutic agent for sepsis and sepsis-induced ALI.

• 한국멀티미디어학회논문지
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• 제20권10호
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• pp.1678-1688
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• 2017

Infiltration is one of detrimental problems occurring in nursing or medical settings. Early detection of infiltration is essential to minimize the risk of injury from infiltration. To perform a preliminary study on the point of care and automated infiltration detection system, bioelectrical impedance was investigated using bioelectrical impedance analyzer. We would like to report experimental results that allow impedance parameters to effectively distinguish infiltration. Electrodes were attached to both sides of the transparent dressing on the fusion site where IV solution was being infused. Then, impedance parameters before and after infiltration were measured as a function of time and frequency. The experimental results are as follows. After infiltration was intentionally induced by puncturing the vein wall with a needle, the resistance gradually decreased with time. That is, when an alternating current having a frequency of 20 kHz was applied to the electrodes, the resistance gradually decreased with time, reflecting the accumulation of IV solution in the extracellular fluid since the current could not pass through the cell membrane. Impedance parameters and equivalent circuit model for human cell were used to examine the mechanism of current flow before and after infiltration, which could be used for early detection of infiltration.

• Journal of Ginseng Research
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• 제47권5호
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• pp.672-680
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• 2023

Background: Korean Red Ginseng (KRG), the steamed root of Panax ginseng, has pharmacological activities for immunological and neurodegenerative disorders. But, the role of KRGE in multiple sclerosis (MS) remains unclear. Purpose: To determine whether KRG extract (KRGE) could inhibit demyelination in corpus callosum (CC) of cuprizone (CPZ)-induced murine model of MS Methods: Male adult mice were fed with a standard chow diet or a chow diet supplemented with 0.2% (w/w) CPZ ad libitum for six weeks to induce demyelination while were simultaneously administered with distilled water (DW) alone or KRGE-DW (0.004%, 0.02 and 0.1% of KRGE) by drinking. Results: Administration with KRGE-DW alleviated demyelination and oligodendrocyte degeneration associated with inhibition of infiltration and activation of resident microglia and monocyte-derived macrophages as well as downregulation of proinflammatory mediators in the CC of CPZ-fed mice. KRGE-DW also attenuated the level of infiltration of Th1 and Th17) cells, in line with inhibited Mrna expression of IFN-γ and IL-17, respectively, in the CC. These positive effects of KRGE-DW mitigated behavioral dysfunction based on elevated plus maze and the rotarod tests. Conclusion: The results strongly suggest that KRGE-DW may inhibit CPZ-induced demyelination due to its oligodendroglial protective and anti-inflammatory activities by inhibiting infiltration/activation of immune cells. Thus, KRGE might have potential in therapeutic intervention for MS.

• 한방재활의학과학회지
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• 제21권3호
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• pp.1-11
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• 2011

Objectives : This study was performed to evaluate the effects of root of Scutellariae Radix(SR) water extract against inflammatory response in the spinal cord injury(SCI). Methods : SCI was induced by mechanical contusion following laminectomy of 10th thoracic vertebra in Sprague-Dawley rat. SR was orally given once a day for 7days after SCI. Myeloperoxidase(MPO) positive neutrophils infiltration was examined. Inducible nitric oxide synthase(iNOS) and tumor necrosis factor-${\alpha}$(TNF-${\alpha}$) expressions were observed with immunohistochemistry. Glial fibrillary acidic protein(GFAP) positive astrocytes were examined using immuno-fluorescence. Results : 1. SR reduced MPO-positive neutrophils infiltration in peri-damage regions of the contusive SCI-induced rats. 2. SR reduced iNOS positive cells in the white matter of the contusive SCI-induced rats. 3. SR reduced TNF-${\alpha}$ positive cells in the gray and white matter of the contusive SCI-induced rats. 4. SR reduced cell number and size of astrocytes in peri-damage regions of the contusive SCI-induced rats. Conclusions : These results suggest that SR plays an inhibitory role against inflammatory response in the SCI.

• 대한예방한의학회지
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• 제10권2호
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• pp.121-129
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• 2006

BACKGROUND : Socheongryong-Tang(小靑龍湯, SCRT), a herbal medicine, has been widely used for the control of respiratory disease in Eastern countries. Recent years SCRT was known as anti-allergic agent. However, its therapeutic mechanisms, especially an inhibitory effect on inflammatory cell infiltration and airway remodeling in allergic asthma are unclear. METHODS : We investigated the effects of SCRT on levels of IL-4, and IFN-g using flow cytometric analysis and infiltration of inflammatory cells in bronchoalveolar lavage fluid(BALF) using cytospin methods in allergen-induced asthma. RESULTS : SCRT decreased levels of IL-4, a Th2-driven cytokine. But INF-g, a Th1-driven cytokine, was not changed. With SCRT treatment, infiltration of inflammatory cells showed reduced tendency. CONCLUSION : In conclusion, we demonstrated that regulation of Th1/Th2 imbalance may be one of mechanism contributed to reduction of inflammatory cell infiltration.

• Geomechanics and Engineering
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• 제13권2호
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• pp.353-370
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• 2017

This paper presents a case study and numerical investigation to study the hydro-mechanical response of a shallow landslide in unsaturated slopes subjected to rainfall infiltration using a coupled model. The coupled model was interpreted in details by expressing the balance equations for soil mixture and the coupled constitutive equations. The coupled model was verified against experimental data from the shearing-infiltration triaxial tests. A real case of shallow landslide occurred on Mt. Umyeonsan, Seoul, Korea was employed to explore the influence of rainfall infiltration on the slope stability during heavy rainfall. Numerical results showed that the coupled model accurately predicted the poromechanical behavior of a rainfall-induced landslide by simultaneously linking seepage and stress-strain problems. It was also found that the coupled model properly described progress failure of a slope in a highly transient condition. Through the comparisons between the coupled and uncoupled models, the coupled model provided more realistic analysis results under rainfall. Consequently, the coupled model was found to be feasible for the stability and seepage analysis of practical engineering problems.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2006년도 춘계 학술발표회 논문집
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• pp.28-33
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• 2006

Shallow failures of slopes in weathered soils are caused by infiltration due to prolonged rainfall. These failures are mainly triggered by the deepening of the wetting band accompanied by a decrease in suction induced by the water infiltration. In this paper, hysteresis on soil-water characteristic curve(SWCC) of granite and gneiss weathered soils are investigated using transient flow analysis respectively. Each case was subjected to artificial rainfall intensities and time duration depending on the laboratory-based drying and wetting processes. The results show that the unsaturated seepage on weathered slopes are very much affected by the initial suction of soils and unsaturated permeability of the soils. In addition, a granite weathered soil has a lower air-entry value, residual matric suction, and wetting front suction and less hysteresis loop than a gneiss weathered soil.

• 한국농공학회:학술대회논문집
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• 한국농공학회 2005년도 학술발표논문집
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• pp.375-380
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• 2005

In Korea, most landslides are occurred during the rainy season from June to September and have a shallow failure plane parallel to the slope. For these types of rainfall-induced failures, the most important factors triggering slope unstability is not the increase of pore water pressure but the decrease of the matric suction of unsaturated soils by rainfall infiltration. So it is essential to landslide hazard assessment that defines the characteristics of infiltration in natural slopes. In this study, field measurements have been carried out in order to monitor in-situ volumetric water contents and ground water table, at several depths and locations on a natural slope. The results show that rainfall infiltration is correlated with antecedent water contents, rainfall intensity and total rainfall. The ground water table was varied sensitively by every rainfall event.

• 동의생리병리학회지
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• 제32권1호
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• pp.75-79
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• 2018

Animal models of atopic dermatitis (AD) are widely used to investigate therapeutic effects of candidates for AD. However, the characteristics of each model are not fully understood. This study was designed to compare the animal models of dermatitis induced by dinitrofluorobenzene (DNFB) and oxazolone (Ox). We investigated the effects of DNFB and Ox on skin thicknesses and weights as well as skin lesions associated with AD such as scale, crust and erythematous eruption, and histopathological changes such as hyperkeratosis, dermal and epidermal hyperplasia and immune cell infiltration in inflamed tissues. Multiple application of 0.5% Ox onto the skin increased skin thickness and weight compared to those of DNFB treated mice, as well as those of normal mice. In addition, topical application of DNFB induced marked scale, crust and erythematous eruption, while Ox induced erythematous eruption and mild scale and crust. Histopathological examination revealed that 0.5% Ox induced marked hyperplasia in the dermis and epidermis, large vesicles, spongiotic changes, mild hyperkeratosis and immune cell infiltration in balb/c mice. These data suggest that multiple applications of Ox can induce chronic AD like dermatitis in balb/c mice.