• Title/Summary/Keyword: node activity

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Hypermethylation and Clinicopathological Significance of RASAL1 Gene in Gastric Cancer

  • Chen, Hong;Pan, Ying;Cheng, Zheng-Yuan;Wang, Zhi;Liu, Yang;Zhao, Zhu-Jiang;Fan, Hong
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.11
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    • pp.6261-6265
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    • 2013
  • Background: Recent studies have suggested that expression of the RAS protein activator like-1 gene (RASAL1) is decreased in gastric carcinoma tissues and cell lines, indicated a role in tumorigenesis and development of gastric cancer. Reduced expression of RASAL1 could result in aberrant increase of activity of RAS signaling pathways in cancer cells. However, the exact mechanism which induces down-regulation of the RASAL1 gene remains unclear. This study aimed to determine the methylation status and regulation of RASAL1 in gastric cancer. Materials and Methods: Using the methylation-specific polymerase chain reaction (MSP), the methylation status of CpG islands in the RASAL1 promoter in gastric cancers and paired adjacent non-cancerous tissues from 40 patients was assessed and its clinicopathological significance was analyzed. The methylation status of RASAL1 in gastric cancer lines MKN-28, SGC-790l, BGC-823, as well as in normal gastric epithelial cell line GES-l was also determined after treatment with a DNA methyltransferase inhibitor, 5-aza-2'-doexycytidine (5-Aza-CdR). RAS activity (GAS-GTP) was assessed through a pull-down method, while protein levels of ERK1/2, a downstream molecule of RAS signaling pathways, were determined by Western blotting. Results: The frequencies of RASAL1 promoter methylation in gastric cancer and paired adjacent non-cancerous tissues were 70% (28/40) and 30% (12/40) respectively (P<0.05). There were significantly correlations between RASAL1 promoter methylation with tumor differentiation, tumor size, invasive depth and lymph node metastasis in patients with gastric cancer (all P<0.05), but no correlation was found for age or gender. Promoter hypermethylation of the RASAL1 gene was detected in MKN-28, SGC-790l and BGC-823 cancer cells, but not in the normal gastric epithelial cell line GES-1. Elevated expression of the RASAL1 protein, a decreased RAS-GTP and p-ERK1/2 protein were detected in three gastric cancer cell lines after treatment with 5-Aza-CdR. Conclusions: Aberrant hypermethylation of the RASAL1 gene promoter frequently occurs in gastric cancer tissues and cells. In addition, the demethylating agent 5-Aza-CdR can reverse the hypermethylation of RASAL1 gene and up-regulate the expression of RASAL1 significantly in gastric cancer cells in vivo. Our study suggests that RASAL1 promoter methylation may have a certain relationship with the reduced RASAL1 expression in gastric cancer.

Respiratory Sinus Arrhythmia: Methods of Measurement and Interpretations of Tonic and Dynamic Vagal Cardiac Drive Index in Psychophysiology of Emotions

  • Estate M.Sokhadze;Lee, Jong-Mi;Park, Mi-Kyung;Sohn, Jin-Hun
    • Proceedings of the Korean Society for Emotion and Sensibility Conference
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    • 2000.11a
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    • pp.81-87
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    • 2000
  • Beat-to-beat changes in heart period (heart period variability, HPV) are mediated by fluctuations in autonomic activity. Spectral analysis is used to quantify such fluctuations in the range of 0.15-0.40 Hz (high frequency, HF), which are influenced primarily by parasympathetic factors. These fluctuations are often referred to as RSA (respiratory sinus arrhythmia), the physiological phenomenon extracted by spectral analysis and other methods including histograms of heart rate ( HR), deviations of HR etc. Respiratory sinus arrhythmia indexing with peak-to-valley method suggested by Grossman et at., (1981) yields a simple range statistic and is quantified on breath-by-breath basis, thus being quite sensitive and less dependent on recording time as compared to spectral analysis. It is strongly recommended to use at least 1 min epoch to asses HF component of HPV and at least 2 min fer low frequency (LF) of HPV and even 5 min far valid clinical assessment. Peak-to-valley statistic is limited to RSA index only, but has its pragmatic advantages. Most important is possibility of its application far relatively small epoch analysis. We used short periods (20,30, 40 sec only) and off-line analysis of RSA using ECG and respiration curve this method of assessment and proved that this method is more practically effective. The RSA index was not so far dependent on respiration pattern differences and reflected actual vagal control of HR and were accompanied by low HR under some high stress conditions and in an aversive affective visual stimulation experiments. Another factor that might modulate cardiac chronotropic response is the interaction of sympathetic and parasympathetic inputs on sino-atrial (SA) node level, because responses to vagal influences are known to be proportional to ongoing sympathetic activity, that is so called accentuated antagonism. Since sympathetic outflow (increment of influences on SA) under negative emotions or stress was high in almost all physiological responses, vagal effects on HR could be therefore potentiated, leading to masking of output cardiac response seen in HPV, In the case of moderate sympathetic activation, on the other hand, autonomic interactions in cardiac control appear to be minimal. Thus RSA index appears to be an effective alternative method to assess and measure spectral HPV.

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Inhibitory Effects of Deer Antler Herbal-Acupuncture Solution on Cathepsin S and L Activity in RA Model Mice

  • Ahn, Hyung-Jun;Yoon, Jong-Hwa;Kim, Kyung-Ho;Lee, Seung-Deok;Kim, Kap-Sung
    • Journal of Acupuncture Research
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    • v.22 no.2
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    • pp.71-81
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    • 2005
  • Objective : Dear antler (Cervus korean TEMMINCK var. mantchuricus Swinhoe) used for traditional immunosuppressive and immuno-activating action. The effect of deer antler herbal-acupuncture(DAH) solution, prepared by water extract method, on cathepsin activities in bone tissues (cartilage and synovial) cells from mouse rheumatoid arthritis (RA) model was studied. The cysteine endoprotease cathepsin mediates degradation of the MHC class II invariant chain (Ii) in human and mouse antigen-presenting cells. The studies described here examine the functional significance of cathepsin inhibition on autoantigen presentation and organ-specific autoimmune diseases in a murine model for RA. Methods : An animal model for RA in BALB/c mice thymectomized 3 days after birth (3d-Tx) was constructed All 3d-Tx BALB/c mice developed autoimmune lesions in the bone tissue cells, starting at 3 weeks of age, and the disease mediated by CD4+ T cells was chronic and progressive. Significant inhibitory effects of DAH solution on cathepsin S and L were observed in each organ in a dose-dependent manner. Moreover, we confirmed that cathepsin S and L activity in each organ were clearly inhibited by DAB solution. When we examined the inhibitory effects of DAH solution against autoantigen-specific T cell responses in vitro, in regional lymph node cells, but not in spleens, from model mice, a significant inhibitory effect of DAB solution was observed in a dose-dependent manner. DAH solution do not block T cell proliferation to Con A, indicated that the dose of DAB solution 10 to $20\;{\mu}g/m{\ell}$ was sufficient to inactivate the autoantigen-specific T cell responses in vitro. In vivo therapeutic effects of DAB solution were examined in a murine model for RA, autoantigen-specific (C-II-specific) T cell response were significantly inhibited in LNCs from DAH solution-treated mice. Results : Iinhibition of cathepsin S and L in vivo alters autoantigen presentation and development of organ-specific autoimmunity in RA model. Conclusion : These data identify selective inhibition of cysteine protease cathepsin S and L as a potential therapeutic strategy for autoimmune disease process such RA. Thus, DAH solution will served as a potent anti-inflammatory and anti-arthritic agents for treatment of human RA.

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Development of Predictive Models for Rights Issues Using Financial Analysis Indices and Decision Tree Technique (경영분석지표와 의사결정나무기법을 이용한 유상증자 예측모형 개발)

  • Kim, Myeong-Kyun;Cho, Yoonho
    • Journal of Intelligence and Information Systems
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    • v.18 no.4
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    • pp.59-77
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    • 2012
  • This study focuses on predicting which firms will increase capital by issuing new stocks in the near future. Many stakeholders, including banks, credit rating agencies and investors, performs a variety of analyses for firms' growth, profitability, stability, activity, productivity, etc., and regularly report the firms' financial analysis indices. In the paper, we develop predictive models for rights issues using these financial analysis indices and data mining techniques. This study approaches to building the predictive models from the perspective of two different analyses. The first is the analysis period. We divide the analysis period into before and after the IMF financial crisis, and examine whether there is the difference between the two periods. The second is the prediction time. In order to predict when firms increase capital by issuing new stocks, the prediction time is categorized as one year, two years and three years later. Therefore Total six prediction models are developed and analyzed. In this paper, we employ the decision tree technique to build the prediction models for rights issues. The decision tree is the most widely used prediction method which builds decision trees to label or categorize cases into a set of known classes. In contrast to neural networks, logistic regression and SVM, decision tree techniques are well suited for high-dimensional applications and have strong explanation capabilities. There are well-known decision tree induction algorithms such as CHAID, CART, QUEST, C5.0, etc. Among them, we use C5.0 algorithm which is the most recently developed algorithm and yields performance better than other algorithms. We obtained data for the rights issue and financial analysis from TS2000 of Korea Listed Companies Association. A record of financial analysis data is consisted of 89 variables which include 9 growth indices, 30 profitability indices, 23 stability indices, 6 activity indices and 8 productivity indices. For the model building and test, we used 10,925 financial analysis data of total 658 listed firms. PASW Modeler 13 was used to build C5.0 decision trees for the six prediction models. Total 84 variables among financial analysis data are selected as the input variables of each model, and the rights issue status (issued or not issued) is defined as the output variable. To develop prediction models using C5.0 node (Node Options: Output type = Rule set, Use boosting = false, Cross-validate = false, Mode = Simple, Favor = Generality), we used 60% of data for model building and 40% of data for model test. The results of experimental analysis show that the prediction accuracies of data after the IMF financial crisis (59.04% to 60.43%) are about 10 percent higher than ones before IMF financial crisis (68.78% to 71.41%). These results indicate that since the IMF financial crisis, the reliability of financial analysis indices has increased and the firm intention of rights issue has been more obvious. The experiment results also show that the stability-related indices have a major impact on conducting rights issue in the case of short-term prediction. On the other hand, the long-term prediction of conducting rights issue is affected by financial analysis indices on profitability, stability, activity and productivity. All the prediction models include the industry code as one of significant variables. This means that companies in different types of industries show their different types of patterns for rights issue. We conclude that it is desirable for stakeholders to take into account stability-related indices and more various financial analysis indices for short-term prediction and long-term prediction, respectively. The current study has several limitations. First, we need to compare the differences in accuracy by using different data mining techniques such as neural networks, logistic regression and SVM. Second, we are required to develop and to evaluate new prediction models including variables which research in the theory of capital structure has mentioned about the relevance to rights issue.

Antioxidant and antiproliferating effects of Setaria italica, Panicum miliaceum and Sorghum bicolor extracts on prostate cancer cell lines (조, 기장, 수수 추출물의 항산화 효과 및 전립선 암세포주 증식 억제 효능)

  • Kim, Jeong-Ho;Cho, Hyun-Dong;Hong, Seong-Min;Lee, Ju-Hye;Lee, Yong-Seok;Kim, Du-Hyun;Seo, Kwon-Il
    • Food Science and Preservation
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    • v.23 no.7
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    • pp.1033-1041
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    • 2016
  • In this study, we evaluated antioxidant and antiproliferating effects of Setaria italica extract (SIE), Panicum miliaceum extract (PME) and Sorghum bicolor extract (SBE). Antioxidant effects of these extracts were determined by assessing DPPH radical scavenging activity, $ABTS^+$ radical scavenging activity, reducing power and superoxide dismutase (SOD)-like activity. From high concentrations ($1,000{\mu}g/mL$) of each extract at DPPH radical scavenging activities of SIE, PME and SBE were 10.5%, 5.5% and 86.8% respectively, $ABTS^+$ radical activities were 4.92%, 5.9% and 62.3% respectively, reducing powers (OD 700) were 0.15, 0.18 and 1.7 respectively, and SOD-like activities were 17.0%, 15.9% and 38.6% respectively. In addition, SBE significantly decreased the cell viability of androgen-sensitive lymph node metastasis type of prostate cancer (LNCaP) cells in a dose-dependent manner. Morphological study of SBE-treated LNCaP cells revealed distorted and shrunken cell masses. SBE-induced cell death was confirmed by observation of nuclear condensation and increased formation of apoptotic bodies. The antiproliferative effect of SBE seems to be associated with the antioxidant activity of its polyphenol content. The results of this study indicate that SBE can exert antioxidant and antiproliferative effects and may be as a useful food material.

Response of the Growth Characteristics and Phytochemical Contents of Pepper (Capsicum annuum L.) Seedlings with Supplemental LED Light in Glass House (LED 보광처리가 고추(Capsicum annuum) 묘의 생장과 Phytochemical 함량에 미치는 영향)

  • Azad, Md. Obyedul Kalam;Chun, Ik-Jo;Jeong, Jeong-Hak;Kwon, Soon-Tae;Hwang, Jae-Moon
    • Journal of Bio-Environment Control
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    • v.20 no.3
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    • pp.182-188
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    • 2011
  • This research was conducted to evaluate the effect of supplemental light-emitting diode (LED) light on growth characteristics and phytochemical content of pepper (Capsicum annuum L.) seedling using LED blue (470 nm, B), red (660 nm, R), blue + red (BR), far red (740 nm, FR) and UV-B (300 nm) light treatment, and without artificial light. Photon flux of LED light was 49, 16, 40, 5.0 and $0.82{\mu}mol\;m^{-2}s^{-1}$ for B, R, BR, FR, and UV-B light, respectively, during experiment. Supplemental LED light duration was $16hr\;day^{-1}$ and UV-B light duration was 10 min. per day after sunset up to 15 days (12 days after germination) of plants age. In our research, growth characteristics and phytochemical content of pepper seedlings were greatly influenced by supplemental LED light compare to control treatment. Red light increased the number of leaves, number of nodes, leaf width and plant fresh weight by 34%, 27%, 50% and 40%, respectively. Blue light increased the leaf length by 13%, and stem length and length of inter node were increased by 17% and 34%, respectively under grown far red light. After 15 days of light treatments phytochemical concentrations of pepper plants were significantly changed. Blue light enhanced the total anthocyanin and chlorophyll concentration by 6 times and 2 times, respectively. Red light increased the total phenolic compound at least two folds meanwhile far red light reduced the ascorbic acid and antioxidant activity 31% and 66%, respectively compared to control treatment.

A Critical Path Search and The Project Activities Scheduling (임계경로 탐색과 프로젝트 활동 일정 수립)

  • Lee, Sang-Un
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.12 no.1
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    • pp.141-150
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    • 2012
  • This paper suggests a critical path search algorithm that can easily draw PERT/GANTT chart which manages and plans a project schedule. In order to evaluate a critical path that determines the project schedule, Critical Path Method (CPM) is generally utilized. However, CPM undergoes 5 stages to calculate the critical path for a network diagram that is previously designed according to correlative relationship and execution period of project execution activities. And it may not correctly evaluate $T_E$ (The Earliest Time), since it does not suggest the way how to determine the sequence of the nodes activities that calculate the $T_E$. Also, the sequence of the network diagram activities obtained from CPM cannot be visually represented, and hence Lucko suggested an algorithm which undergoes 9 stages. On the other hand, the suggested algorithm, first of all, decides the sequence in advance, by reallocating the nodes into levels after Breadth-First Search of the network diagram that is previously designed. Next, it randomly chooses nodes of each level and immediately determines the critical path only after calculation of $T_E$. Finally, it enables the representation of the execution sequence of the project activity to be seen precisely visual by means of a small movement of $T_E$ of the nodes that are not belonging to the critical path, on basis of the $T_E$ of the nodes which belong to the critical path. The suggested algorithm has been proved its applicability to 10 real project data. It is able to get the critical path from all the projects, and precisely and visually represented the execution sequence of the activities. Also, this has advantages of, firstly, reducing 5 stages of CPM into 1, simplifying Lucko's 9 stages into 2 stages that are used to clearly express the execution sequence of the activities, and directly converting the representation into PERT/GANTT chart.

Microtuberization and Morphological Development by Culture Condition In Vitro Node Culture of Potato (감자절간 기내배양에서 소괴경의 형성과 형태적 발달)

  • Hwang, Hye-Yeon;Lee, Young-Bok
    • Journal of Plant Biotechnology
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    • v.34 no.4
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    • pp.331-338
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    • 2007
  • One-node stem pieces ca. 1 cm in length containing a axillary bud and a fully expanded leaf were obtained from it in vitro plants of potato (Solanum tuberosum L.). Leaves were removed and the nodes were cultured on the MS medium to investigate the effects of temperature, day length, sucrose, and CCC in microtuber formation and development. The fresh weight of microtubers after 80 days increased significantly at 8% sucrose and $20^{\circ}C$ compared with $28^{\circ}C$. The tuberization and development were reduced at $28^{\circ}C$ except short-day treatment of 8 hours at 8% sucrose. The fresh weight and diameter were increased on the culture medium added CCC 500 mg/L. The potato tuberization was promoted under short daylength, and it showed great effect by treatment with the CCC. Though the tuberization was promoted at low temperature of $20^{\circ}C$ in a histologic change of an axillary bud part cell of a potato, the cells were able to observe the swelling growth. Swelling growth of tissue was stimulated in the darkness and was more remarkable by addition of CCC. In particular, in the visual ratio of cell division for each position in the tissue, the cortex part showed larger ratio of cell expansion than that of the pith part. The effect of CCC was identified at 8% sucrose in the darkness. The effect of CCC was not showed in sucrose 3% under long daylength of 16 hours. As a result, the fact of a substance with AGPase important for starch composition was certified by the result with the inclose of AGPase activity on high concentration of sucrose, CCC, and dark treatment by which tuber formation and development are promoted.

Effect of Panax ginseng on the Graft-versus-Host Reaction, Production of Leucocyte Migration Inhibitory Factor and Expulsion of Adult Trichinella spiralis in Mice (인삼이 이식편대숙주반응, 대식세포유주저지반응 및 Trichinella spiralis의 expulsion에 미치는 영향)

  • Ha, Tai-You;Lee, Jeong-Ho;Kim, Sang-Hyung
    • The Journal of the Korean Society for Microbiology
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    • v.21 no.1
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    • pp.133-144
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    • 1986
  • This study was undertaken to assess the effect of ginseng administration on T lymphocyte induced local xenogenic graft-versus-host(GVM) reactions which were induced with thymocyte, spleen cell and lymph node cell of ICR mice. Mice received daily 10mg of 70% alcohol ginseng extract oral1y for 100days and control mice remained untreated for the same period of time. The cells from donor mice were injected intradermally into the closely shaven abdominal skin of Sprague-Dawley rats for GVH tests. The thymocyte from control(ginseng-untreated) mice showed a negative local GVH reaction, whereas thymocyte from experimental(ginseng-treated) mice showed a positive reaction with the rate of 17.4%. When spleen cells were injected, the incidence of positive local GVH reaction was 66.7% among ginseng-treated mice, as opposed to incidence of 45.5% of positive local GVH reaction among control mice. The incidence of positive local GVH reaction of the lymph node cells when injected into a recipient was 71.4% among ginseng-treated mice as compared with that of 18.9% among control mice. The relationship between spleen cell inoculum and intensity of the local GVH reaction was assessed in ginseng-untreated mice. The intensity of GVH reaction clearly appears to be dose related. In ginseng-treated mice, a minimum of $1{\times}10^7$ spleen cell was required for production of positive local GVH reaction with almost linear relationship up to an inoculum of $5{\times}10^8$ cells. In control mice, however, a minimum of $1{\times}10^8$ spleen cells was required for positive GVH reaction. These results strongly suggest that the ginseng administration augments significantly the local xenogenic GVH reaction which was used to assess T lymphocyte function and immunocompetence of mice and in addition to this, these results appear to support previous suggestions that the local GVH reaction consitutes a qualitative test of the functional activity of T lymphocytes. These results may be the first to induce local GVH reaction, employing rats as recipient and mice as donor. This study was also desingned to investigate some of the effects of ginseng extract on lymphocyte-macrophage interactions. This was accomplished by in vitro quantification of 1) migratory inhibitory factor(MIF) synthetic capacity of splenic lymphocytes in mice previously primed with ginseng 2) MIF responsiveness of mouse peritoneal macrophages or chicken peripheral leucocytes under the presence of ginseng extract 3) migration ability of chicken peripheral leucocytes by direct stimulation of ginseng extract or ginseng saponin and 4) immunosuppressive effects of immunosuppressants such as cyclophosphamide, cyclosporin A or dexamethasone. Mice divided equally into the ginseng and the saline groups, which received intraperitoneally daily 0.2ml of ginseng absolute alcohol-extract(5mg/ml) and same amount of saline for 15 days, respectively. The cellular immune responsiveness of these mice was assayed 15 days after ginseng pretreatment. Splenic lymphocytes of mice treated with ginseng, when stimulated with sensitized specific-antigen such as sheep red blood cells or toxoplasmin, or with polyclonal activator concanavalin A, produced significantly more MIF than those of control saline group. MIF responsiveness of normal mouse macrophages was significantly augmented when assayed under the presence of ginseng extract (1mg/ml). The migratory ability of normal chicken leucocytes in the absence of MIF was significantly decreased by the stimulation of ginseng extract alone. MIF response was significantly decreased by immunosuppressants and this impaired response was not restored by ginseng pretreatment. This study was additionally performed to evaluate the effect of ginseng on the expulsion of adult Trichinella spiralis in mice. ICR mice were infected experimentally by esophageal incubation of 300 T. spiralis infective muscle larvae prepared by acid-pepsin digestion of infected mice. and received oral administration of 70% alcohol ginseng extract(10mg/mouse/day) for the indicated days plus 4 days before infection. At various times after infection, the number of adult T. spiralis worms in small intestines was determined. Interestingly, ginseng-treatment was accompanied by accelerated expulson of T. spiralis. These results led to the conclusion that Panax ginseng caused some enhancing effect on GVH reaction, macrophage migration inhibition reaction and expulsion of T. spiralis. In addition these results suggested that the mechanisms responsible for this enhancement of ginseng may be chiefly or partially due to nonspecific stimulation of cell-mediated immune response.

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Change of FDG Uptake According to Radiation Dose on Squamous Cell Carcinoma of the Head and Neck (두경부종양에서 방사선조사량에 타른 FDG-PET의 변화양상)

  • Lee Sang-wook;Kim Jae-Seung;Im Ki Chun;Ryu Jin Sook;Lee Hee Kwan;Kim Jong Hoon;Ahn Seung Do;Shin Seong Soo;Yoon Sang Min;Song Siyeol;Park Jin-hong;Moon Dae Hyuk;Choi Eun Kyung
    • Radiation Oncology Journal
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    • v.22 no.2
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    • pp.98-105
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    • 2004
  • Purpose : To evaluate whether positron omission tomography (PET) with 2-[F-18]fluoro-2-deoxy-D-giucose(FDG) can be used to predict of early response to definitive aim radlotherapy (RT) in squamous cell carcinoma of the head and neck using response rate and locoreglonal control as study endpoints. Materials and Methods : Twenty-two patients with head and neck cancer underwent a FDG-PET study before RT, after a flrst dose of 45 Gy, and after a second dose on more 4han 70 Gy. Standard uptake value (SUV) was calculated for primary tumor (n=22) and neck lymph node (n:10). Attenuation corrected PET scans acquired 60 min after tracer injection were used for evaluation of FDG uptake In tumors. A quantitative FDG uptake index was expressed as Suvlean (corrected for iean body mass). The follow-up time was at least 5 months (range S-1 S months). Results : A total of 22 primary tumors and 10 metastatic lymph nodes were analyzed In FDG-PET. In the first PET study the mean SUVlean the primary tumors and nodes were 5.4 (SD, 2.5) and 4.6 (SD, 2.3), respectively. In the second PET, study peformed after 46 Gy RT the mean SUV in primary tumor and node decreased to 2.9 (SD, 1.9, p<0.001) and 1.7 (SD, 1.3) respectively. in the third PET study peformed at the full dose (more than 70 Gy), RT the mean SUV In the primary tumors and nodes decreased to 2.3 (SD, 1.5, p<0.001) and 1.5 (SD, 1 .1) respectively. Conclusions: FDG uptake In tumors showed a significant decrease after the 45 Gy and more than 70 Gy of RT for squamous cell carcinoma of the head and neck. Reduction of metabolic activity after 46 Gy of radiotherapy Is closely correlated with radiation response.