• Title/Summary/Keyword: Dose enhancement

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Enhancement of Immunological Activities in Mice by Oral Administration of Pectic Polysaccharides from Eleutherococcus senticosus

  • Sung, Ji-Yun;Yoon, Taek-Joon;Yu, Kwang-Won;Lee, Kwang-Ho;Lee, Ho
    • Food Science and Biotechnology
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    • v.15 no.1
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    • pp.117-121
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    • 2006
  • Ability of pectic polysaccharides isolated from Eleutherococcus senticosus EN-3 to inhibit tumor metastasis and induce antigen-specific immune response after oral administration in mice was assessed. Consecutive oral administration of EN-3 before tumor inoculation dramatically inhibited tumor metastasis produced by colon26-M3.1 and B16-BL6 cells. When Peyer's patch cells isolated from mouse intestine were co-cultured with EN-3, proliferation of Peyer's patch cells was induced. Mice co-administered with EN-3 and ovalbumin (OVA) showed significantly higher production of OVA-specific IgA in intestinal washing as well as IgG in serum than those administered with OVA alone. Payer's patch cells of mice immunized with OVA plus EN-3 showed much higher proliferating activity than those of mice immunized with OVA alone. Proliferating activity increased dose-dependently, indicating EN-3 specifically enhanced mucosal immune response to OVA. These results suggested EN-3 could significantly stimulate Peyer's patch cells either non-specifically or antigen-specifically, possibly playing important role in enhancement of mucosal and systemic immune systems.

Enhancement of Paracellular Transport of Heparin Disaccharide Across Caco-2 Cell Monolayers

  • Kim, Yeong-Shik;Cho, So-Yean;Kim, Jong-Sik;Li, Hong;Shim, Chang-Koo;Linhardt, Robert-J.
    • Archives of Pharmacal Research
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    • v.25 no.1
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    • pp.86-92
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    • 2002
  • The enhancement of paracellular transport of heparin disaccharide using several absorption enhancers across Caco-2 cell monolayers was tested . The cytotoxicity of these enhancers was also examined. The enhancing effects by Quillaja saponin, diponin glycyrrhizinate, $18{\beta}-glycyrrhetinic$ acid, sodium caprate and taurine were determined by changes in transepithelial electrical resistance (TEER) and the amount of heparin disaccharide transported across Caco-2 cell monolayers. Among the absorption enhancers, $18{\beta}-glycyrrhetinic$ acid arid taurine decreased TEER and increased the permeability of heparin disaccharide in a dose-dependent and time-dependent manner with little or negligible cytotoxicity. Our results indicate that these absorption enhancers can widen the tight junction, which is a dominant paracellular absorption route of hydrophilic compounds . It is highly possible that these absorption enhancers can be applied as pharmaceutical excipients to improve the transport of macromolecules and hydrophilic drugs having difficulty in permeability across the intestinal epithelium.

Inhibitory Effect of Bee Venom Toxin on Lung Cancer NCI H460 Cells Growth Through Induction of Apoptosis via Death Receptor Expressions

  • Hur, Keun Young;Song, Ho Sueb
    • Journal of Acupuncture Research
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    • v.31 no.1
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    • pp.121-130
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    • 2014
  • Objectives : I investigated whether bee venom inhibit cell growth through enhancement of death receptor expressions in the human lung cancer cells, NCI-H460. Methods : Bee venom(1-5 ${\mu}g/ml$) inhibited the growth of NCI-H460 lung cancer cells by the induction of apoptotic cell death in a dose dependent manner. Results : Consistent with apoptotic cell death, expression of TNF-R1, TNF-R2, FAS, death receptors(DR) 3, 4, 5 and 6 was increased in the cells. Expression of DR downstream pro-apoptotic proteins including Caspase-8, -3, -9 was upregulated and Bax was concomitantly overwhelmed the expression of Bcl-2. NF-kB were inhibited by treatment with bee venom in NCI-H460 cells through TNF response change led by TNF-R1 and TNF-R2. Conclusions : These results suggest that bee venom should exert anti-tumor effect through induction of apoptotic cell death in NCI-H460 human lung cancer cells via enhancement of death receptor expression, and that bee venom could be a promising agent for preventing and treating lung cancer.

Inhibitory Effects of Bee Venom on Growth of A549 Lung Cancer Cells via Induction of Death Receptors

  • Jang, Dong Min;Song, Ho Sueb
    • Journal of Acupuncture Research
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    • v.30 no.1
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    • pp.57-70
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    • 2013
  • This study was to investigated the effects of the bee venom on inhibition of cell growth via upregulation of death receptor expression in the A549 human lung cancer cells. Bee venom(1-5 ${\mu}g$/ml) inhibited the growth of A549 lung cancer cells by the induction of apoptotic cell death in a dose dependent manner. Consistent with apoptotic cell death, expression of TNFR1, Fas, death receptors(DR) 3, 4 and 6 was increased in the cells. Expression of DR downstream pro-apoptotic proteins including caspase-3, -9 and Bax was concomitantly increased, but the expression of Bcl-2, NF-${\kappa}B$ were inhibited by treatment with bee venom in A549 cells. Moreover, deletion of DR3, DR4 by small interfering RNA significantly reversed bee venom-induced cell growth inhibitory effect, whereas Apo3L strengthened anti-proliferative effect of bee venom through enhancement of DR3 expression. These results suggest that bee venom should exert anti-tumor effect through induction of apoptotic cell death in lung cancer cells via enhancement of death receptor expression, and that bee venom could be a promising agent for preventing and treating lung cancer.

Design and development of enhanced criticality alarm system for nuclear applications

  • Srinivas Reddy, Padi;Kumar, R. Amudhu Ramesh;Mathews, M. Geo;Amarendra, G.
    • Nuclear Engineering and Technology
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    • v.50 no.5
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    • pp.690-697
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    • 2018
  • Criticality alarm systems (CASs) are mandatory in nuclear plants for prompt alarm in the event of any criticality incident. False criticality alarms are not desirable as they create a panic environment for radiation workers. The present article describes the design enhancement of the CAS at each stage and provides maximum availability, preventing false criticality alarms. The failure mode and effect analysis are carried out on each element of a CAS. Based on the analysis, additional hardware circuits are developed for early fault detection. Two different methods are developed, one method for channel loop functionality test and another method for dose alarm test using electronic transient pulse. The design enhancement made for the external systems that are integrated with a CAS includes the power supply, criticality evacuation hooter circuit, radiation data acquisition system along with selection of different soft alarm set points, and centralized electronic test facility. The CAS incorporating all improvements are assembled, installed, tested, and validated along with rigorous surveillance procedures in a nuclear plant for a period of 18,000 h.

Up-Regulation of RANK Expression via ERK1/2 by Insulin Contributes to the Enhancement of Osteoclast Differentiation

  • Oh, Ju Hee;Lee, Na Kyung
    • Molecules and Cells
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    • v.40 no.5
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    • pp.371-377
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    • 2017
  • Despite the importance of the receptor activator of nuclear factor (NF)-kappaB ligand (RANKL)-RANK signaling mechanisms on osteoclast differentiation, little has been studied on how RANK expression is regulated or what regulates its expression during osteoclastogenesis. We show here that insulin signaling increases RANK expression, thus enhancing osteoclast differentiation by RANKL. Insulin stimulation induced RANK gene expression in time- and dose-dependent manners and insulin receptor shRNA completely abolished RANK expression induced by insulin in bone marrow-derived monocyte/macrophage cells (BMMs). Moreover, the addition of insulin in the presence of RANKL promoted RANK expression. The ability of insulin to regulate RANK expression depends on extracellular signal-regulated kinase 1/2 (ERK1/2) since only PD98059, an ERK1/2 inhibitor, specifically inhibited its expression by insulin. However, the RANK expression by RANKL was blocked by all three mitogen-activated protein (MAP) kinases inhibitors. The activation of RANK increased differentiation of BMMs into tartrate-resistant acid phosphatase-positive ($TRAP^+$) osteoclasts as well as the expression of dendritic cell-specific transmembrane protein (DC-STAMP) and d2 isoform of vacuolar ($H^+$) ATPase (v-ATPase) Vo domain (Atp6v0d2), genes critical for osteoclastic cell-cell fusion. Collectively, these results suggest that insulin induces RANK expression via ERK1/2, which contributes to the enhancement of osteoclast differentiation.

Effects of Swainsonine on the Humoral Immune Response of Lipopolysaccharide

  • Chae, Byeong-Suk;Ahn, Young-Keun;Kim, Joung-Hoon
    • Archives of Pharmacal Research
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    • v.20 no.6
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    • pp.545-549
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    • 1997
  • Effects of swainsonine (SW;8${\alpha}$, ${\beta}$-indolizidine-${\alpha}$, $2{\alpha}$8-triol from Locoweed) on the humoral immune responses of lipopolysaccharide (LPS) wer studied in ICR mice. Mice were divided into 4 groups (10 mice/group), and LPS was given to each mouse 1 hr after i.p. injection with 3.7 mg/kg of swainsonine, by i.p. injection twice a week for 14 days at a dose of 2 mg/kg. Humoral immune responses were evaluated by hemagglutination (HA) titer and splenic plaque forming cells (PFC). The results of this study were summarized as follows: Mice administrated each of LPS and SW showed significant enhancement of the weight ratios of spleen to body, HA titer, 2-mercaptoethanol-resistant HA(MER-HA) titer and PFC compared with those in controls. However, the LPS plus SW treatment decreased HA titer, MER-HA titer and PFC corresponding to humoral immunity, as compared with those in the mice treated with LPS alone. These findings indicated that LPS significantly enhanced humoral immune responses, but their enhancement effects were lowered somewhat by SW.

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Abdominal Digital Radiography with a Novel Post-Processing Technique: Phantom and Patient Studies (새로운 후처리 기술을 이용한 복부 디지털 방사선 촬영: 팬텀과 환자 연구)

  • Hyein Kang;Eun Sun Lee;Hyun Jeong Park;Byung Kwan Park;Jae Yong Park;Suk-Won Suh
    • Journal of the Korean Society of Radiology
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    • v.81 no.4
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    • pp.920-932
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    • 2020
  • Purpose The aim of this study was to evaluate the diagnostic image quality of low dose abdominal digital radiography processed with a new post-processing technique. Materials and Methods Abdominal radiographs from phantom pilot studies were post-processed by the novel and conventional post-processing methods of our institution; the proper dose for the subsequent patient study of 49 subjects was determined by comparing image quality of the two preceding studies. Two radiographs of each patient were taken using the conventional and derived dose protocols with the proposed post-processing method. The image details and quality were evaluated by two radiologists. Results The radiation dose for the patient study was derived to be half of the conventional method. Overall half-dose image quality with the proposed method was significantly higher than that of the conventional method (p < 0.05) with moderate inter-rater agreement (κ = 0.60, 0.47). Conclusion By applying the new post-processing technique, half-dose abdominal digital radiography can demonstrate feasible image quality compared to the full-dose images.

Evaluation of superficial dose for Postmastectomy using several treatment techniques (유방전절제술을 시행한 환자에서 치료기법에 따른 피부선량 평가)

  • Song, Yong Min;Choi, Ji Min;Kim, Jin Man;Kwon, Dong Yeol;Kim, Jong Sik;Cho, Hyun Sang;Song, Ki Won
    • The Journal of Korean Society for Radiation Therapy
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    • v.26 no.2
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    • pp.225-232
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    • 2014
  • Purpose : The purpose of this study was to evaluate the surface and superficial dose for patients requiring postmastectomy radiation therapy(PMRT) with different treatment techniques. Materials and Methods : Computed tomography images were acquired for the phantom(I'mRT, IBA) consisting of tissue equivalent material. Hypothetical chestwall and lung were outlined and modified. Five treatment techniques(Wedged Tangential; WT, 4-field IMRT, 7-field IMRT, TOMO DIRECT, TOMO HELICAL) were evaluated using only 6MV photon beam. GafChromic EBT3 film was used for dose measurements at the surface and superficial dose. Surface dose profiles around the phantom were obtained for each treatment technique. For superficial dose measurements, film were used inside the phantom and analyzed superficial region for depth from 1-6mm. Results : TOMO DIRECT showed the highest surface dose by 47~70% of prescribed dose, while 7-field IMRT showed the lowest by 35~46% of prescribed dose. For the WT, 4-field IMRT and 7-field IMRT, superficial dose were measured over 60%, 70%, and 80% for 1mm, 2mm, and 5mm depth, respectively. In case of TOMO DIRECT and TOMO HELICAL, over 75%, 80%, and 90% of prescribed dose was measured, respectively. Surface and superficial dose range were uniform in overall chestwall for the 7-field IMRT and TOMO HELICAL. In contrast, Because of the dose enhancement effect with oblique incidence, The dose was gradually increased toward the obliquely tangential angle for the WT and TOMO DIRECT. Conclusion : For PMRT, TOMO DIRECT and TOMO HELICAL deliver the higher surface and superficial doses than treatment techniques based linear accelerator. It showed adequate dose(over 75% of prescribed dose) at 1mm depth in skin region.

Immunostimulant and Anti-Tumor Activity of Crude Extracts of Galium aparine L. (팔선초 물 추출물의 면역자극 및 항종양 활성)

  • Yoon, Taek-Joon;Lee, Chang-Kwon;Park, Tae-Kyu;Lee, Kwang-Ho
    • Korean Journal of Pharmacognosy
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    • v.36 no.4 s.143
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    • pp.332-337
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    • 2005
  • We here demonstrate the evidence of increased anti-tumor and immunostimulating activities of crude extracts (GAL) from Galium. aparine L. In experimental lung metastasis of colon26-M3.1 carcinoma or B16-BL6 melanoma cells, prophylactically intravenous (i.v) administration of GAL significantly inhibited lung metastasis in a dose-dependant manner. In an in vitro cytotoxicity analysis, GAL at the concentration up to $500\;{\mu}g/ml$ did not affect the growth of B16-BL6 melanoma cells. In contrast, GAL showed the enhancement of splenocyte proliferating activity in a dose-dependent manner. Peritoneal macrophages stimulated with GAL produced various cytokines such as $1L-1{\beta},\;TNF-{\alpha},\;IFN-{\gamma}$ and IL-12. These data suggest that GAL has an antitumor activity to inhibit tumor metastasis, and its antitumor effects is associated with activation of nonspecific immnune related cells.