• Title/Summary/Keyword: induced current

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Chitosan Microspheres Containing Bordetella bronchiseptica Antigens as Novel Vaccine Against Atrophic Rhinitis in Pigs

  • Kang, Mi-Lan;Kang, Sang-Gyun;Jiang, Hu-Lin;Guo, Ding-Ding;Lee, Deog-Yong;Rayamahji, Nabin;Seo, Yeon-Soo;Cho, Chong-Su;Yoo, Han-Sang
    • Journal of Microbiology and Biotechnology
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    • v.18 no.6
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    • pp.1179-1185
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    • 2008
  • The immune-stimulating activities of Bordetella bronchiseptica antigens containing dermonecrotoxin (BBD) loaded in chitosan microspheres (CMs) have already been reported in vitro and in vivo with a mouse alveolar macrophage cell line (RAW264.7) and mice. Therefore, this study attempted to demonstrate the successful induction of mucosal immune responses after the intranasal administration of BBD loaded in CMs (BBD-CMs) in colostrum-deprived pigs. The BBD was introduced to the CMs using an ionic gelation process involving tripolyphosphate (TPP). Colostrum-deprived pigs were then directly immunized through intranasal administration of the BBD-CMs. A challenge with a field isolate of B. bronchiseptica was performed ten days following the final immunization. The BBD-specific IgG and IgA titers, evident in the nasal wash and serum from the vaccinated pigs, increased with time (p<0.05). Following the challenge, the clinical signs of infection were about 6-fold lower in the vaccinated pigs compared with the nonvaccinated pigs. The grades for gross morphological changes in the turbinate bones from the vaccinated pigs were also significantly lower than the grades recorded for the nonvaccinated pigs (p<0.001). Therefore, the mucosal and systemic immune responses induced in the current study would seem to indicate that the intranasal administration of BBD-CMs may be an effective vaccine against atrophic rhinitis in pigs.

Groundwater inflow rate estimation considering excavation-induced permeability reduction in the vicinity of a tunnel (터널 굴착으로 인한 터널인접 절리암반 투수계수 감소를 고려한 터널 내 지하수 유입량 산정방법)

  • Moon, Joon-Shik
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.15 no.3
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    • pp.333-344
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    • 2013
  • This paper discussed about the effect of permeability reduction of the jointed rock mass in the vicinity of a tunnel which is one of the reasons making large difference between the estimated ground-water inflow rate and the measured value. Current practice assumes that the jointed rock mass around a tunnel is a homogeneous, isotropic porous medium with constant permeability. However, in actual condition the permeability of a jointed rock mass varies with the change of effective stress condition around a tunnel, and in turn effective stress condition is affected by the ground water flow in the jointed rock mass around the tunnel. In short time after tunnel excavation, large increase of effective tangential stress around a tunnel due to stress concentration and pore-water pressure drop, and consequently large joint closure followed by significant permeability reduction of jointed rock mass in the vicinity of a tunnel takes place. A significant pore-water pressure drop takes place across this ring zone in the vicinity of a tunnel, and the actual pore-water pressure distribution around a tunnel shows large difference from the value estimated by an analytical solution assuming the jointed rock mass around the tunnel as a homogeneous, isotropic medium. This paper presents the analytical solution estimating pore-water pressure distribution and ground-water inflow rate into a tunnel based on the concept of hydro-mechanically coupled behavior of a jointed rock mass and the solution is verified by numerical analysis.

Topology Optimization Application for Initial Platform Design of 10 MW Grade Floating Type Wave-wind Hybrid Power Generation System (10MW급 부유식 파력-풍력 복합발전 시스템 플랫폼 초기설계를 위한 위상최적화 응용)

  • Song, Chang Yong;Lee, Kangsu;Hong, Keyyong
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.19 no.3
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    • pp.194-202
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    • 2016
  • This study aims to review a topology optimization based on finite element analysis (FEA) for conceptual design of platform in the 10MW class floating type wave-wind hybrid power generation system (WHPGS). Two topology optimization theories, density method (DM) and homogenization design method (HDM) were used to check which one is more effective for a simplified structural design problem prior to the topology optimization of platform of WHPGS. From the results of the simplified design problem, the HDM was applied to the topology optimization of platform of WHPGS. For the conceptual platform design of WHPGS, FEA model was created and then the structural analysis was performed considering offshore environmental loads at installation site. Hydrodynamics analysis was carried out to calculate pressure on platform and tension forces in mooring lines induced from the offshore environmental loads such as design wave and current. Loading conditions for the structural analysis included the analysis results from the hydrodynamic analysis and the weights of WHPGS. Boundary condition was realized using inertia relief method. The topology optimization of WHPGS platform was performed using the HDM, and then the conceptual arrangement of main structural members was suggested. From the results, it was confirmed that the topology optimization might be a useful tool to design the conceptual arrangement of main structural members for a newly developed offshore structure such as the floating type WHPGS.

Active hexose correlated compound potentiates the antitumor effects of low-dose 5-fluorouracil through modulation of immune function in hepatoma 22 tumor-bearing mice

  • Cao, Zhiyun;Chen, Xuzheng;Lan, Lan;Zhang, Zhideng;Du, Jian;Liao, Lianming
    • Nutrition Research and Practice
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    • v.9 no.2
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    • pp.129-136
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    • 2015
  • BACKGROUND/OBJECTIVES: A variety of immunomodulators can improve the efficacy of low-dose chemotherapeutics. Active hexose correlated compound (AHCC), a mushroom mycelia extract, has been shown to be a strong immunomodulator. Whether AHCC could enhance the antitumor effect of low-dose 5-fluorouracil (5-FU) via regulation of host immunity is unknown. MATERIALS/METHODS: In the current study Hepatoma 22 (H22) tumor-bearing mice were treated with PBS, 5-FU ($10mg{\cdot}kg^{-1}{\cdot}d^{-1}$, i.p), or AHCC ($360mg{\cdot}kg^{-1}{\cdot}d^{-1}$, i.g) plus 5-FU, respectively, for 5 d. $CD^{3+}$, $CD^{4+}$, $CD^{8+}$, and NK in peripheral blood were detected by flow cytometry. ALT, AST, BUN, and Cr levels were measured by biochemical assay. IL-2 and $TNF{\alpha}$ in serum were measured using the RIA kit and apoptosis of tumor was detected by TUNEL staining. Bax, Bcl-2, and TS protein levels were measured by immunohistochemical staining and mRNA level was evaluated by RT-PCR. RESULTS: Diet consumption and body weight showed that AHCC had no apparent toxicity. AHCC could reverse liver injury and myelosuppression induced by 5-FU (P < 0.05). Compared to mice treated with 5-FU, mice treated with AHCC plus 5-FU had higher thymus index, percentages of $CD^{3+}$, $CD^{4+}$, and NK cells (P < 0.01), and ratio of $CD^{4+}$/$CD^{8+}$ (P < 0.01) in peripheral blood. Radioimmunoassay showed that mice treated with AHCC plus 5-FU had the highest serum levels of IL-2 and $TNF{\alpha}$ compared with the vehicle group and 5-FU group. More importantly, the combination of AHCC and 5-FU produced a more potent antitumor effect (P < 0.05) and caused more severe apoptosis in tumor tissue (P < 0.05) compared with the 5-FU group. In addition, the combination of AHCC and 5-FU further up-regulated the expression of Bcl-2 associated X protein (Bax) (P < 0.01), while it down-regulated the expression of B cell lymphoma 2 (Bcl-2) (P < 0.01). CONCLUSIONS: These results support the claim that AHCC might be beneficial for cancer patients receiving chemotherapy.

A study on the behaviour of pre-existing single piles to adjacent shield TBM tunnelling from three-dimensional finite element analyses (3차원 유한요소해석을 통한 shield TBM 터널 근접시공에 의한 인접 단독말뚝의 거동에 대한 연구)

  • Jeon, Young-Jin;Jeon, Seung-Chan;Jeon, Sang-Joon;Lee, Cheol-Ju
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.22 no.1
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    • pp.23-46
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    • 2020
  • In the current work, a series of three-dimensional finite element analyses have been carried out to understand the behaviour of pre-existing single piles to adjacent tunnelling by considering the tunnel face pressures and the relative location of pile tips with respect to the tunnel. The numerical modelling has analysed the effect of the face pressures on the pile behaviour. The analyses concentrate on the ground settlements, the pile head settlements, the axial pile forces and the shear stress transfer mechanism at the pile-soil interface. The head settlements of the pile (the vertical distance between the pile and the tunnel: 0.25D, where D is the tunnel diameter) directly above the tunnel crown with the face pressure 50% of the in-situ horizontal soil stress at the tunnel springline decreased by about 38% compared to corresponding settlements with a face pressure 25% of the in-situ horizontal soil stress at the tunnel springline. Furthermore, it was found that the smaller the face pressure, the larger the tunnelling-induced ground movements and the axial pile forces were and the higher the degree of the shear strength mobilisation at the pile-soil interface. When the piles were outside the tunnel influence zone, compressive pile forces were developed due to tunnelling. It has been found that the ground settlements and the pile settlements are heavily affected by the face pressures and the position of the pile tip relative to the tunnel. In addition, the computed results have been compared with relevant studies previously reported in literature. The behaviour of the piles has been extensively examined and analysed by considering the key features in great detail.

Artist and History: Looking at the current problems of teaching art history in art school (미술가와 역사-미술사 교육의 한계와 전망)

  • Cho, Eun-Jung
    • The Journal of Art Theory & Practice
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    • no.2
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    • pp.49-74
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    • 2004
  • It has been frequently pointed out that the established art history with the stylistic and iconographic interpretations and monographic analysis is fallen behind the currency of modern art. Among those who claimed the crisis in the discipline of art history, there is a suggestion that the art historical study should be fostered by other factors in the fields of the humanities. The so called New Art History or 'visual Culture Studies' insists that art history has to be restructured to integrate the broader study of culture and society, and by now, such an opinion is not a novelty at all. One of the most significant yet overlooked elements that induced the new currency of art history is properties of contemporary art that conflict the traditional claim of art historians. Although the idea that art is not purely aesthetic but that it has many other functions has been brought up by the art historians, it was the artists that provoked such a perception. When Arthur C. Danto and Hans Belting proclaimed the End of Art and Art History in the 1980s, the concept of art has been changed radically through the avant-garde tendency of Modernism and a new pluralism of Postmodernism. One dominant concern that strikes art historians is to find a new approach to art, since the traditional method and goal of analysis for past art and past art history seem unavailable. The perplexity arising from the situation is intensified in the field of teaching art, especially for those who teach art history in art school. Basically art history is a pursuit of learning of art in history, and its purpose is to reconcile the present with the past and the future as well. Since Modernism, as it is confusing sometimes because it implies the present state, somehow art became considered 'tradition-less'. It does not mean that a work of art stands aloof from the past attainments, hut modern art imposed itself on a task seeking after the new for its own sake, turning its back on the tradition. And now in the era of Postmodernism, an historians face the requirement to revaluate the whole history of art including modernism. The necessity of art history in art education is indisputable, but methods and contents in the academic courses should he reexamined now. Because artists' concept of history and past art has been altered, and art history as a humanistic discipline can only maintain its identity through incorporation with art itself. Academics teaching art history, or, strictly speaking, past works of art and history, to the student in art school, confront with the need to rethink the object of art history and its meaning to the artists.

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Inhibitory Effects of Ginsenoside Metabolites, Compound K and Protopanaxatriol, on $GABA_C$ Receptor-Mediated Ion Currents

  • Lee, Byung-Hwan;Hwang, Sung-Hee;Choi, Sun-Hye;Kim, Hyeon-Joong;Lee, Joon-Hee;Lee, Sang-Mok;Ahn, Yun Gyong;Nah, Seung-Yeol
    • The Korean Journal of Physiology and Pharmacology
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    • v.17 no.2
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    • pp.127-132
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    • 2013
  • Ginsenosides, one of the active ingredients of Panax ginseng, show various pharmacological and physiological effects, and they are converted into compound K (CK) or protopanaxatriol (M4) by intestinal microorganisms. CK is a metabolite derived from protopanaxadiol (PD) ginsenosides, whereas M4 is a metabolite derived from protopanaxatriol (PT) ginsenosides. The ${\gamma}$-aminobutyric acid $receptor_C$ ($GABA_C$) is primarily expressed in retinal bipolar cells and several regions of the brain. However, little is known of the effects of ginsenoside metabolites on $GABA_C$ receptor channel activity. In the present study, we examined the effects of CK and M4 on the activity of human recombinant $GABA_C$ receptor (${\rho}$ 1) channels expressed in Xenopus oocytes by using a 2-electrode voltage clamp technique. In oocytes expressing $GABA_C$ receptor cRNA, we found that CK or M4 alone had no effect in oocytes. However, co-application of either CK or M4 with GABA inhibited the GABA-induced inward peak current ($I_{GABA}$). Interestingly, pre-application of M4 inhibited $I_{GABA}$ more potently than CK in a dose- dependent and reversible manner. The half-inhibitory concentration ($IC_{50}$) values of CK and M4 were $52.1{\pm}2.3$ and $45.7{\pm}3.9{\mu}M$, respectively. Inhibition of $I_{GABA}$ by CK and M4 was voltage-independent and non-competitive. This study implies that ginsenoside metabolites may regulate $GABA_C$ receptor channel activity in the brain, including in the eyes.

RhGLP-1 (7-36) protects diabetic rats against cerebral ischemia-reperfusion injury via up-regulating expression of Nrf2/HO-1 and increasing the activities of SOD

  • Fang, Yi;Liu, Xiaofang;Zhao, Libo;Wei, Zhongna;Jiang, Daoli;Shao, Hua;Zang, Yannan;Xu, Jia;Wang, Qian;Liu, Yang;Peng, Ye;Yin, Xiaoxing
    • The Korean Journal of Physiology and Pharmacology
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    • v.21 no.5
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    • pp.475-485
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    • 2017
  • The present study aimed to explore the neuroprotective effect and possible mechanisms of rhGLP-1 (7-36) against transient ischemia/reperfusion injuries induced by middle cerebral artery occlusion (MCAO) in type 2 diabetic rats. First, diabetic rats were established by a combination of a high-fat diet and low-dose streptozotocin (STZ) (30 mg/kg, intraperitoneally). Second, they were subjected to MCAO for 2 h, then treated with rhGLP-1 (7-36) (10, 20, $40{\mu}g/kg$ i.p.) at the same time of reperfusion. In the following 3 days, they were injected with rhGLP-1 (7-36) at the same dose and route for three times each day. After 72 h, hypoglycemic effects were assessed by blood glucose changes, and neuroprotective effects were evaluated by neurological deficits, infarct volume and histomorphology. Mechanisms were investigated by detecting the distribution and expression of the nuclear factor erythroid-derived factor 2 related factor 2 (Nrf2) in ischemic brain tissue, the levels of phospho-PI3 kinase (PI3K)/PI3K ratio and heme-oxygenase-1 (HO-l), as well as the activities of superoxide dismutase (SOD) and the contents of malondialdehyde (MDA). Our results showed that rhGLP-1 (7-36) significantly reduced blood glucose and infarction volume, alleviated neurological deficits, enhanced the density of surviving neurons and vascular proliferation. The nuclear positive cells ratio and expression of Nrf2, the levels of P-PI3K/PI3K ratio and HO-l increased, the activities of SOD increased and the contents of MDA decreased. The current results indicated the protective effect of rhGLP-1 (7-36) in diabetic rats following MCAO/R that may be concerned with reducing blood glucose, up-regulating expression of Nrf2/HO-1 and increasing the activities of SOD.

Effect of Subculture on Plant Regeneration in Rice Callus Culture (벼 Callus의 계대배양(繼代培養)이 식물체(植物體) 재분화(再分化)에 미치는 영향(影響))

  • Sohn, Jae Keun;Lee, Seong Mok;Kim, Kyung Min
    • Current Research on Agriculture and Life Sciences
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    • v.9
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    • pp.21-28
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    • 1991
  • The effect of subculture intervals and passages on plant regeneration from seed-derived callus was determined. Regeneration capacity of callus varied with rice cultivars and subculture intervars tested. The callus subcultured every 2 weeks produced more plants than that of 4 weeks. The calli from a Tongil-type rice cultivar, Milyang 23, lost easily their regeneration ability when the calli were subcultured every 2 weeks and 4 weeks. The callus induced from a japonica cultivar, "Yeongdeogbyeo", showed to maintain high frequency(>70%) of plant regeneration when it was subcultured every 2-week intervals. Casein hydrolysate supplemented in callus induction medium enhanced callus growth and its regeneration. High frequency of plant regeneration was obtained from the calli transferred on $N_6$ medium supplemented with kinetin(2mg/1) and NAA(1mg/1). The subcultured calli in the medium supplemented with casein hydrolysate(2 g/1), myo-inositol(200mg/1) and thiamine-HCl(2mg/1) increased the frequency of embryogenic callus formation and plant regeneration.

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Treatment Strategies for Primary Central Nervous System Lymphoma (원발성 중추신경계 림프종의 치료전략)

  • Kim, Il-Man;Lee, Chang Young;Son, Eun Ik;Kim, Dong Won;Yim, Man Bin;Kim, Sang Pyo
    • Journal of Korean Neurosurgical Society
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    • v.30 no.3
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    • pp.334-341
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    • 2001
  • Objective : We have currently changed treatment strategies to methotrexate(MTX)-based preirradiation chemotherapy with subsequent planned radiation for the initial therapy of primary central nervous system lymphoma (PCNSL). The aim of this study was to evaluate the results of treating PCNSL with chemotherapy plus radiotherapy (CRT) or radiotherapy(RT) alone. Method and Material : This study involved 10 females and 3 males patients with a mean age of 54.2 years. All patients underwent surgery, open(8 cases) or stereotactic biopsy(5 cases) for histological diagnosis. Eleven tumors were diffuse large B-cell lymphomas. Tumor volume change in the follow-up images and survival time were evaluated in patients treated with CRT and RT alone. In the beginning, two patients received ProMACE-Cytabom chemotherapeutic regimen, but did not complete the course and died of progressive tumor 8 and 9 months after diagnosis, respectively. One patient died at 6 months before chemotherapy. These three were excluded from the survival analysis. Five patients(RT group) completed full courses of cranial irradiation with or without boost. For the current combined modality treatment, high-dose MTXbased chemotherapy(systemic and intrathecal MTX, IV vincristine, and oral procarbazine) followed by whole brain irrdiation to 45Gy to tumor was introduced in 5 patients of CRT group. Result : A complete response was achieved in three of five who received RT only and in all of five who received CRT. All patients in CRT groups are in disease free status at a mean 23 months following therapy. The RT group patients refused any additional salvage therapy at tumor relapse and survived at mean 20 months from diagnosis. The Karnofsky performance status improved in eight of ten patients with treatment. The treatment toxicity included leukoencephalopathy in RT group and severe leukopenia, transient hepatitis, avascular necrosis of femoral head, hearing loss, and amenorrhea in CRT group, respectively. Conclusion : The combined modality therapy of MTX-based chemotherapy plus radiotherapy for PCNSL may enhance tumor response and improve patient survival. The patients who received CRT should be carefully followed up because of the higher risk of treatment-induced late neurotoxicity.

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