• Title/Summary/Keyword: active agent

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A Study of the Distinctive Characteristics of Government Funded Research Institutes Engaged in Technological Cooperation with SMEs (중소기업의 기술협력에서 출연연의 차별적 특징에 관한 연구)

  • Jun, Seung-pyo;Park, Hun;Yoo, Jae Young
    • Journal of Korea Technology Innovation Society
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    • v.20 no.3
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    • pp.607-641
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    • 2017
  • Recently, there has been an increase in government-wide demand for technological cooperation between government funded research institutes (GFRIs) and small and medium-sized enterprises (SMEs), while there remain a tension between positive and negative views regarding the support given by GFRIs to encourage the technological innovation of SMEs. Although preceding studies have found that the support given by GFRIs to SMEs tends to have the effect of enhancing the technological innovation outcomes of SMEs, this study examines the question of why the agent that provides technological cooperation to SMEs should be limited to GFRIs. To answer this question, in this study, we first examined the qualitative changes in the external technological cooperation behavior of SMEs over time, from 2007 to 2014. Next, we performed cluster analysis to examine whether there were distinctive characteristics of SMEs that engage in technological cooperation with GFRIs, compared to the various other alternatives available as technological cooperation partners for SMEs. Lastly, to help us identify the characteristics of the companies that technologically cooperate with GFRIs and to facilitate the administrative or practical effort to find companies that would be strong candidates for technological cooperation with GFRIs, we used discriminant analysis to define a discriminant formula for such companies likely to engage in technological cooperation. The results of this study were as follows. First, GFRIs were the most competitive -- as demonstrated by the highest level of satisfaction, etc. - compared to the other alternatives for external technological cooperation available to SMEs. This confirmed the necessity for GFRIs to provide technological cooperation to SMEs. Secondly, the issue of whether the small and medium-sized enterprise had engaged in technological cooperation specifically with GFRIs was found not to be a very significant factor in distinguishing these companies. It was found, however, that SMEs engaged in technological cooperation were distinctive, regardless of the type of institution involved in the technological cooperation. Thirdly, SMEs that were in technological cooperation with GFRIs had the characteristics of being already active in joint research and already familiar with utilizing the systems available for governmental support. The findings of this study offers various insights relevant to establishing national R&D strategies using GFRIs and improving the efficiency of policies and administrative practices intended to help GFRIs assist SMEs.

Antioxidative Effect and Component Analysis of Eriobotrya japonica Leaf Extracts (비파엽 추출물의 항산화 효능과 성분분석)

  • Kim, Su-Ji;Park, Jin-O;Park, Soo-Nam
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.38 no.1
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    • pp.57-65
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    • 2012
  • In the present study, the antioxidative properties, inhibitory activity on tyrosinase, and active components of Eriobotrya japonica (E. japonica) leaf extract were investigated. The free radical (1,1-diphenyl-2-picrylhydrazyl, DPPH) scavenging activity ($FSC_{50}$) of extract/fraction of E. japonica leaf was in the order 50 % ethanol extract ($22.625{\mu}g/mL$) < ethyl acetate fraction (6.75) < deglycosylated aglycone fraction (5.06). Reactive oxygen species (ROS) scavenging activities ($OSC_{50}$) of fraction/extracton ROS generated in $Fe^{3+}-EDTA/H_2O_2$ system using the luminol-dependent chemiluminescenceassay were investigated. $OSC_{50}$ of the ethyl acetate fraction, deglycosylated aglycone fraction, and ethanol extract were 0.75, 0.79, and $1.61{\mu}g/mL$, respectively. The cellular protective effects of E. japonica leaf extract on the rose-bengal sensitized photohemolysis of human erythrocytes were investigated. The protective effects of extract/fraction of E. japonica leaf were increased in a in a concentration dependent manner ($5{\sim}50{\mu}g/mL$). Especially, ${\tau}50$ of ethyl acetate fraction at concentrations of $10{\mu}g/mL$ and $50{\mu}g/mL$ showed the most protective effects at 390.8 min and 1471.5 min. The inhibitory effect ($IC_50$) on tyrosinase of E. japonica leaf extracts was higher than arbutin, known as a skin-whitening agent. The order of inhibitory effects was acetate fraction ($75.25{\mu}g/mL$) < 50 % extract (74.1) < deglycosylated aglycone fraction (43.35). TLC of the ethyl acetate fraction showed 7 bands (EJL 1 - EJL 7). HPLC of the aglycone fraction exhibited 2 peaks, kaempferol and quercetin. The amounts of kaempferol and quercetin were 53.7 and 46.3 %. respectively. Therefore, The amounts of kaempferol and its glucoside were a little bit higher than quercetin and its glucoside in E. japonica leaf extract. Accordingly, these findings suggest that extracts/fractions of E. japonica leaf can function as antioxidants in biological systems, especially skin exposed to UV radiation, and protect cellular membranes against ROS. Thus, the extract/fraction of E. japonica leaf may be used in novel functional cosmetics as antioxidants against skin photoaging.

Clinical Study of Topotecan as Second-Line Treatment in Small Cell Lung Cancer (소세포폐암의 2차요법으로서의 Topotecan의 치료효과)

  • Kim, Hak-Ryul;Yang, Sei-Hoon;Jeong, Eun-Taik
    • Tuberculosis and Respiratory Diseases
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    • v.52 no.3
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    • pp.230-240
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    • 2002
  • Background : The majority of chemotherapy-treated small cell lung cancers(SCLC) patients eventually recur. Although many patients are in excellent physical condition at the time of recurrence, few drugs or drug combinations are capable of effecting a tumor regression in this setting. Topotecan, a topoisomerase I inhibitor, is one of the more widely studied single afents in SCLC. The aim of this study was to determine the response rate, survival and toxicity of topotecan as a second line traeatment SCLC. Materials and Methods : 19 patients with measurable SCLC, progressive during the first line chemotherapy (9 cases) or recurrent after the first line chemotherpy(10 cases), were enrolled in this study. Topotecan was administered as a 30-minute daily infusion at a dose of 1.5mg/$m^2$ for 5 consecutive days, every 3 weeks. Results : The overall response rate was 26.3%(5/19, CR 2, PR 3, SD 3, PD 11). The median survival was 24 weeks. The response rate and survival were poor in the nonresponders during first chemotherapy, those who were refractory to the first chemotherapy(recurrent within 3 months after completion of first chemotherapy) and extensive disease, but the results were not statistically significant. The toxicities were mainly hematologic and anemia grade III 1/90, leukopenia grade III 6/90 IV 4/90, thrombocytopenia grade III 1/90 IV 1/90, vomiting grade III 1/90 of cycles were occurred. There was no treatment-related deaths due to severe myelosuppression. Conclusion : Topotecan can be an active second line chemotherapeutic agent for treating SCLC.

Importance of Strain Improvement and Control of Fungal cells Morphology for Enhanced Production of Protein-bound Polysaccharides(β-D-glucan) in Suspended Cultures of Phellinus linteus Mycelia (Phellinus linteus의 균사체 액상배양에서 단백다당체(β-D-glucan)의 생산성 향상을 위한 균주 개량과 배양형태 조절의 중요성)

  • Shin, Woo-Shik;Kwon, Yong Jung;Jeong, Yong-Seob;Chun, Gie-Taek
    • Korean Chemical Engineering Research
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    • v.47 no.2
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    • pp.220-229
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    • 2009
  • Strain improvement and morphology investigation in bioreactor cultures were undertaken in suspended cultures of Phellinus linteus mycelia for mass production of protein-bound polysaccharides(soluble ${\beta}$-D-glucan), a powerful immuno-stimulating agent. Phellineus sp. screened for this research was identified as Phellinus linteues through ITS rDNA sequencing method and blast search, demonstrating 99.7% similarity to other Phellinus linteus strains. Intensive strain improvement program was carried out by obtaining large amounts of protoplasts for the isolation of single cell colonies. Rapid and large screening of high-yielding producers was possible because large numbers of protoplasts ($1{\times}10^5{\sim}10^6\;protoplasts/ml$) formed using the banding filtration method with the cell wall-disrupting enzymes could be regenerated in relatively high regeneration frequency($10^{-2}{\sim}10^{-3}$) in the newly developed regeneration medium. It was demonstrated that the strains showing high performances in the protoplast regeneration and solid growth medium were able to produce 5.8~6.4%(w/w) of ${\beta}$-D-glucan and 13~15 g/L of biomass in stable manners in suspended shake-flask cultures of P. linteus mycelia. In addition, cell mass increase was observed to be the most important in order to enhance ${\beta}$-D-glucan productivity during the course of strain improvement program, since the amount of ${\beta}$-D-glucan extracted from the cell wall of P. linteus mycelia was almost constant on the unit biomass basis. Therefore we fully investigated the fungal cell morphology, generally known as one of the key factors affecting cell growth extent in the bioreactor cultures of mycelial fungal cells. It was found that, in order to obtain as high cell mass as possible in the final production bioreactor cultures, the producing cells should be proliferated in condensed filamentous forms in the growth cultures, and optimum amounts of these filamentous cells should be transferred as active inoculums to the production bioreactor. In this case, ideal morphologies consisting of compacted pellets less than 0.5mm in diameter were successfully induced in the production cultures, resulting in shorter period of lag phase, 1.5 fold higher specific cell growth rate and 3.3 fold increase in the final biomass production as compared to the parallel bioreactor cultures of different morphological forms. It was concluded that not only the high-yielding but also the good morphological characteristics led to the significantly higher biomass production and ${\beta}$-D-glucan productivity in the final production cultures.

A Clinical Study of Tuberculous Lymphadenitis (결핵성 림프절염 373 예의 임상적 고찰)

  • Park, Hye-Jung;Ryoo, Hun-Mo;Shin, Kyeong-Cheol;Park, Jong-Seon;Chung, Jin-Hong;Lee, Kwan-Ho;Kim, Chang-Ho;Park, Jae-Yong;Jung, Tae-Hoon;Han, Sung-Beom;Jeon, Young-Jun;Hyun, Dae-Sung;Lee, Sang-Chae
    • Tuberculosis and Respiratory Diseases
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    • v.48 no.5
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    • pp.730-739
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    • 2000
  • Background : The aim of this study was to analyze the clinical manifestations and efficacy of treatment regimens in order to determine the adequate combination of anti-tuberculotic agents and duration of treatment for tuberculous lymphadenitis. Methods : We made a review of 373 patients with tuberculous lymphadenitis, who were admitted to four medical college hospitals in Taegu Korea from 1989 to 1998, and their diagnoses were confirmed histologically and bacteriologically. Results : The incidence of tuberculous lymphadenitis was 71.3% in women and 57.7% were between the ages of 20 and 39 years. The most common symptom was painless swelling. The most commonly involved lymph nodes were unilateral superficial cervical lymph node groups. Tuberculous lymphadenitis was accompanied with active pulmonary tuberculosis, commonly. The sensitivity of fine needle aspiration(FNA) in tuberculous lymphadenitis was 79.6%, and 92.2% of the patients had a strong positive reaction to the tuberculin skin test. The most commonly prescribed anti-tuberculotic regimen was the combination of INH, RMP, EMB, and PZA(62.6 %). Eighty percent of patient were treated for 9-12 months. There was no significantly difference in the recurrence rate of tuberculous lymphadenitis between the combinations of anti-tuberculotic agent, including INH and RMP, and between the durations of treatment, for a period of 6 months of more. Conclusion : The combination of FNA cytologic examination and tuberculin skin test may be helpful in the diagnosis of tuberculous lymphadenitis. We propose that the combination of anti-tuberculotic agents, INH, RMP, EMB, and PZA, be prescribed to patients for 6 to 9 months.

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Anti-Inflammatory and Moisturizing Effect of Centella Extracts Fermented in Jeju Lava Water (제주용암해수로 숙성된 병풀 추출물의 항염 및 보습 효과)

  • Lee, Jeesun;Myung, Cheol Hwan;Lee, Ji Eun;Jo, Mi-Rae;Kim, Hong-Suk;Lee, Na-Young;Woo, Heedong;You, Jaeeun;Jo, Hae;Hwang, Jae Sung
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.45 no.4
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    • pp.363-372
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    • 2019
  • The leaves and stems of Centella asiatica have a long history of their usage as a medicine for the treatment of skin diseases such as ulcers and psoriasis, especially in Asia. Triterpenoids, the active components of Centella asiatica including asiaticoside, madecasosside, asiatic acid and madecassic acid, have shown to inhibit skin inflammation as well as improve skin photoaging. The main objective of this study is to investigate whether the Centella asiatica ripened with lava seawater which is rich in minerals known to be beneficial to human body can provide anti-inflammatory and moisturizing effects to skin. HPLC analysis showed that the concentration of triterpenoids increased further after ripening Centella asiatica with lava seawater. In order to confirm the inflammatory efficacy of the extract of the extract of the ripened Centella asiatica, the production of NO in LPS-activated RAW 264.7 cells and the expression of inflammatory cytokines in PM10 or UVB-induced HaCaT cells were observed. We found that the extract of the ripened Centella asiatica inhibited the expression of NO, IL-6, IL-8, and TNF-a and had higher inhibitory effect compared to the extract of the non-ripened Centella asiatica. In order to confirm the skin moisturizing effect, we investigated the synthesis of HA in HaCaT cells. The result showed HA production was enhanced in a concentration-dependent manner from the ripened group, while there was no efficacy from the non-ripened group. Taken together, it is concluded that the extract of the Centella asiatica ripened with lava seawater was effective in anti-inflammation and moisturization.

A Study on Teaching-Learning and Evaluation Methods of Environmental Studies in the Middle School (중학교 "환경" 교과의 교수.학습 및 평가 방법 연구)

  • 남상준
    • Hwankyungkyoyuk
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    • v.7 no.1
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    • pp.1-17
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    • 1994
  • This study was performed to determine appropriate teaching-learning and evaluation methods for Environmental Studies. To promote the relevance of our study to the needs of the schools and concerned educational communities of environmental education, we reviewed related literature, conducted questionnaire surveys, interviewed related teachers and administrator, held meetings with experts, and field-tested our findings. For selecting and developing teaching-learning methods of Environmental Studies, findings of educational research in general are considered. moreover, principles of environmental education, general aim of environmental education, orientations of environmental education, and developmental stages of middle school students in educational psychology were attended. In addition, relevance to the purpose of the Environmental Studies curriculum, appropriateness for value inquiry as well as knowledge inquiry, small group centered class organization, social interaction centered teaching-learning process, regional environmental situation, significance of personal environment, evaluation methods of Environmental Studies, multi- and inter-disciplinary contents of the Environmental Studies textbook, suitability to the evaluation methods of Environmental Studies, and emphasis on the social interaction in teaching-learning process were regarded. It was learned the Environmental Studies can be taught most effectively in via of holding discussion sessions, conducting actual investigation, doing experiment-practice, doing games and plate, role-playing and carrying out simulation activities, and doing inquiry. These teaching-learning methods were field-tested and proved appropriate methods for the subject. For selecting and developing evaluation method of Environmental Studies, such principles and characteristics of Environmental Studies as objective domains stated in the Environmental Studies curriculum, diversity of teaching-learning organization, were appreciated. We categorized nine evaluation methods: the teacher may conduct questionnaire surveys, testings, interviews, non-participatory observations; they may evaluate student's experiment-practice performances, reports preparation ability, ability to establish a research project, the teacher may ask the students to conduct a self-evaluation, or reciprocal evaluation. To maximize the effect of these methods, we further developed an application system. It considered three variables, that is, evaluates, evaluation objectives domains, and evaluation agent, and showed how to choose the most appropriate methods and, when necessary, how to combine uses of different methods depending on these variables. A sample evaluation instrument made on the basis of this application system was developed and tested in the classes. The system proved effective. Pilot applications of the teaching-learning methods and evaluation method were made simultaneously; and the results and their implications are as follows. Discussion program was applied in a lesson dealing with the problems of waste disposal, in which students showed active participation and creative thinking. The evaluation method used in this lesson was a multiple-choice written test for knowledge and skills. It was shown that this evaluation method and device are effective in helping students' revision of the lesson and in stimulating their creative interpretations and responces. Pupils showed great interests in the actual investigation program, and this programme was proved to be effective in enhancing students' participation. However, it was also turned out that there must be pre-arranged plans for the objects, contents and procedures of survey if this program is to effective. In this lesson, non-participatory observation methods were used with a focus on the attitudes of students. A scaled reported in general description rather than in grade. Experiment-practice programme was adopted in a lesson for purifying contaminated water and in this lesson, instruction objectives were properly established, the teaching-learning process was clearly specified and students were highly motivated. On the other hand, however, it was difficult to control the class when some groups of students require more times to complete their experiment, and sometimes different results. As regards to evaluation, performance observation test were used for assessing skills and attitudes. If teachers use well-prepared Likert scale, evaluation of all groups within a reasonablely short period of time will be possible. The most effective and successful programme in therms of students' participation and enjoyment, was the 'ah-nah-bah-dah-market' program, which is kind of game of the flea market. For better organized program of this kind, however, are essential, In this program, students appraise their own attitudes and behavior by responding to a written questionnaire. In addition, students were asked to record any anecdotes relating to self-appraisal of changes on one's own attitudes and behaviours. Even after the lesson, students keep recording those changes on letters to herself. Role-playing and simulation game programme was applied to a case of 'NIMBY', in which students should decide where to located a refuse dumping ground. For this kind of programme to e successful, concepts and words used in the script should be appropriate for students' intellectual levels, and students should by adequately introduced into the objective and the procedures of the lessons. Written questionnaire was used to assess individual students' attitudes after the lesson, but in order to acquire information on the changes of students' attitudes and skills, pre-test may have to be made. Doing inquiry programme, in which advantages in which students actually investigated the environmental influence of the areas where school os located, had advantages in developing students' ability to study the environmental problems and to present the results of their studies. For this programme to be more efficient, areas of investigation should be clearly divided and alloted to each group so that repetition or overlap in areas of study and presentation be avoided, and complementary wok between groups bee enhanced. In this programme, teacher assessed students' knowledge and attitudes on the basis of reports prepared by each group. However, there were found some difficults in assessing students' attitudes and behaviours solely on the grounds of written report. Perhaps, using a scaled checklist assessing students' attitudes while their presentation could help to relieve the difficulties.

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The current status and control measures of BSE in the worldwide (국내, 외 광우병의 발생 현황과 대응 방안)

  • Yoo, Han-Sang
    • 한국환경농학회:학술대회논문집
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    • 2009.07a
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    • pp.273-282
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    • 2009
  • The transmissible spongiform encephalopathies (TSEs) disease group are fatal neurodegenerative disorders affecting a wide range of hosts. The group includes kuru and Creutzfeldt-Jakob disease (CJD) in humans, scrapie in sheep and goats and Bovine spongiform encephalopathy (BSE) in cattle. The exact nature of the infectious agent involved in the transmission of these diseases remains controversial. However, a central event in their pathogenesis is the accumulation in infected tissues of an abnormal form of a host-encoded protein, the prion protein (PrP). Whereas the normal cellular protein is fully sensitive to protease ($PrP^{sen}$), the disease-associated prion protein ($PrP^d$) is only partly degraded ($PrP^{res}$), its amino-terminal end being removed. BSE was first reported in the mid-80s in the UK. Ten years later, a new form of human prion disease, variant CJD (vCJD) developed in the wake of the BSE epidemic, and there is now strong scientific evidence that vCJD was initiated by the exposure of humans to BSE-infected tissues, thus indicating a zoonotic disease. However, the ban on the feeding of animal-derived proteins to ruminants, and the apparent lack of vertical transmission of BSE, have led to a decline in the incidence of the disease within cattle herd and therefore, an assumed decreased risk for human contacting vCJD. The origin of the original case(s) of BSE still remains an enigma even though three hypotheses have been raised. Hypotheses are i) sheep- or goat-derived scrapie-infected tissues included in meat and bone meal fed to cattle, ii) a previously undetected sporadic or genetic bovine TSE contaminating cattle feed or iii) originating from a human TSE through animal feed contaminated with human remains. A host cellular membrane protein ($PrP^C$), which is abundant in central nervous system tissue, appear to be conformationally altered in the diseased host into a prion protein ($PrP^{Sc}$). This $PrP^{Sc}$ is detergent insoluble and partially protease-resistant ($PrP^{res}$). The term $PrP^{res}$ is normally used to describe the protein detected after protease treatment, in techniques such as Western immunoblotting, and enzyme-linked immunosorbant assay using fresh/frozen tissue. Immunohistochemistry may performed with formalin-fixed tissues. Also, clinical signs of the BSE are one of the major diagnostic indicators. Recently, atypical forms (known as H- and L-type) of BSE have appeared in several European countries, Japan, Canada and the United States. An unusual case was also reported in a miniature zebu. The atypical BSE fall into two groups based on the relative molecular mass (Mm) of the unglycosylated $PrP^{res}$ band relative to that of classical BSE, one of the higher Mm (H-type) and the other lower (L-type). Both types have been detected worldwide as rare cases in older animals, at a low prevalence consistent with the possibility of sporadic forms of prion diseases in cattle. This raises the unwelcome possibility that vCJD could increase in the human population. Now, active surveillance program against BSE is going on in Korea. In regional veterinary service lab, ELISA is applied to screen the BSE in slaughter and confirmatory tests by Western immunoblotting and immunohistochemisty are carried out if there are positive or suspect in the screening test. Also, the ruminant feed ban is rigorously enforced. Removal of specified risk materials such as brain and spinal cord from cattle is mandatory process at slaughter to prevent the infected material from entering the human food chain.

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Sagantang-induced Apoptotic Cell Death is Associated with the Activation of Caspases in AGS Human Gastric Carcinoma Cells (사간탕 처리에 의한 AGS 인체 위암세포의 caspase 활성 의존적 apoptosis 유발)

  • Park, Cheol;Hong, Su Hyun;Choi, Sung Hyun;Lee, Se-Ra;Leem, Sun-Hee;Choi, Yung Hyun
    • Journal of Life Science
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    • v.25 no.12
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    • pp.1384-1392
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    • 2015
  • Sagantang (SGT), a Korean multiherb formula comprising six medicinal herbs, Paeonia lactiflora Pall., Belamcanda chinensis (L.) DC, Gardenia jasminoides Ellis, Poria cocos Wolf, Cimicifuga heracleifolia Komarov, and Artractylodes japonica Koidzumi, was recorded in “Dongeuibogam.” The present study investigated the anticancer potential of SGT in AGS human gastric carcinoma cells. The results indicated that SGT treatment significantly inhibited the growth and viability of AGS cells in a dose-dependent manner, which was associated with the induction of apoptotic cell death, as evidenced by the formation of apoptotic bodies, in addition to chromatin condensation and DNA fragmentation, and the accumulation of annexin-V positive cells. The induction of apoptotic cell death by the SGT treatment was associated with up-regulation of Fas protein expression, truncation of Bid, and down-regulation of the anti-apoptotic Bcl-2 protein. The SGT treatment also effectively induced the loss of mitochondrial membrane potential, which was associated with the activation of caspases (caspase-3, -8, and -9) and degradation of poly (ADP-ribose) polymerase. However, a pan-caspase inhibitor significantly blocked the SGT-induced apoptosis and growth suppression in AGS cells. This study suggests that SGT induces caspase-dependent apoptosis through an extrinsic pathway by upregulating Fas, as well as through an intrinsic pathway by modulating Bcl-2 family members in AGS cells. The results suggest that SGT may be a potential chemotherapeutic agent for the control of human gastric cancer cells. However, further studies will be needed to confirm the potential of SGT in cancer prevention and therapy in an in vivo model and to identify biological active compounds of SGT.

Studies on Anisakis Type Larvae (Anisakis 형(型) 유충(幼蟲)에 관한 연구(硏究))

  • Lim, Jung Teck
    • Korean Journal of Veterinary Research
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    • v.15 no.2
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    • pp.293-307
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    • 1975
  • As it has been known recently that anisakis type larvae harbouring in marine fishes are a causal agent of zoonosis to human and probably to land living mammal animals, attention was focused on the study on the larvae in an aspect of epidemiology or epizootiology. The present work was conducted from 1966 to 1975 for i) survey on the harbouring status of anisakis type larvae in marine fishes of this country, ii) observation on the response to the experimental infestation of the larvae to the pigs, in the reason that they could well fetid raw fish viscera occasionally containing the larvae as a high protein source of swine food, and iii) observation on the larval resistance and response to vermicidal agents for the purpose of prevention of the larval infection to the mammal animals. The data obtained in the studies were summarized as follows: 1. In the survey on the status of larvae harbouring in main species of marine fishes of this country, 15 species, a total of 1,940 fishes, were observed and the result was summarized in table 2. Average number of larvae, in upper rank of 5 out of all 15 species of fishes, were as highest as 156 larvae ranging 74 to 450 in Pseudosciaena manchurica (chamjogi), 54.5 ranging 15 to 240 in Trichiurus haumela (kalchi), 35.6 ranging 8 to 112 in Trachurus japonica (junggengi), 30.6 ranging 4 to 65 in Parapristipama trilineatum (benjari) and 20.5 ranging 3 to 48 in Nibea argentata (boguchi) respectively. In morphological observation, size of the larvae in the fishes were varied, ranging from 2 to 32mm long, and a tendency to larger size and number of larvae in the fishes, which were wider sea migration, higher age and lager bodily size, was observed The favorite places harbouring the larvae in fishes were mainly around the intraperitoneal viscera such as mesentery, omentum, liver, pyloric suspensory, fat tissue and cloaca, and rarely in body muscles of fish. Fishes heartily infested with the larvae showed stunted growth decreased egg formation and severe damage of liver. 2. In the experimental infestation of the larvae to normal pigs, as illustrated in table 3, a group with large dose of larvae (a total of 1,800 larvae, 300 larvae Per dose, twice in a dart for 3 days) showed acute clinical syndrome terminatine death with a week course, whereas two groups with less dose of larvae (a total of 180~360 larvae, 10 larvae per dose, at 5 days interval for 70~180 days) showed subclinical syndrome with remarkably stunted growth as. much as approximately one half of body size in contest to the control pigs. In the pathological findings, a group with large dose of larvae showed macroscopically larvae penetrating to the gastric wall with severe gastroenteritis, and histopathologically various acute lesions caused by active larvae penetration into the wall of stomach and interstine, whereas two groups with less dose of larvae showed chronic lesions such as hypertrophy and verminous granulomatous swelling of gastric wall, suggesting strongly the possibility of natural infestation of larvae to swine. 3. In the resistance of the larvae to the chemical solutions, the larvae tolerated for 2 days in 15 percent solution of sodium chloride and acetic acid, and for 7 days in 70 percent solution of ethyl alcohol. In the resistance to the temperature, the larvae died within 1 second at $62^{\circ}C$ and tolerated for 24 hours at $-3^{\circ}C$, 12 hours $-5^{\circ}C$ respectively. 4. For the experiment on the vermicidal effect to larvae, general vermicidal drugs such as Neguvon, Combantrin, antimony Potassium, piperazine adipate and piperazine dihydrochloride, oxidizer such as potassium permanganate and potassium chlorate, and dyes such as gentian violet and crystal violet were used, and among them, as illustrated in table 6, potassium permanganate was proved as the best. In the successive test for the practical use of potassium permanganate, vermicidal effect in seawater solution of potassium permanganate and common-water solution of potassium permanganate were compared, and then retested by dipping the fish viscera including the larvae into the two different solutions of potassium permanganate. The result through these tests indicated that 0.01 percent common water and sea-water solution of potassium permanganate could be apparently recommended as a preventive vermicidal solution, having 90 to 100 percent vermicidal effect by dipping for 12 to 24 hours even though sea-water solution of potassium permanganate had a tendency to slightly less effect than the common-water solution of potassium permanganate (Table 8).

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