• Title/Summary/Keyword: re-induction

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Inhibition of Proliferation and Induction of Apoptosis by EGCG in Human Osteogenic Sarcoma (HOS) Cells

  • Ji Sang-Jin;Han Dong-Hoon;Kim Jeong-Hee
    • Archives of Pharmacal Research
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    • v.29 no.5
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    • pp.363-368
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    • 2006
  • EGCG [(-)-epigallocatechin-3-gallate], a major component of green tea has been considered as a major antioxidant constituent. In addition to having been considered for cancer treatment as a chemopreventive and chemotherapeutic agent, EGCG has recently been attributed an anti-proliferative effect. We re-examined the latter finding in this study and added specific focus on the ability of EGCG to induce apoptosis in human osteogenic sarcoma (HOS) cells. Antiproliferative action of EGCG $(IC_{50}=35.3{\pm}6.0{\mu}g/mL)$ appeared to be linked to apoptotic cell death based on morphological changes, chromosomal DNA degradation, and an increase in the $sub-G_1$ apoptotic cell population. Treatment of HOS cells with EGCG gradually activated caspase-3, an established inducer of apoptotic cell death.

Pulse Multiplication in Autotransformer Based AC-DC Converters using a Zigzag Connection

  • Singh, Bhim;Gairola, Sanjay
    • Journal of Power Electronics
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    • v.7 no.3
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    • pp.191-202
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    • 2007
  • This paper deals with pulse multiplication in zigzag connected autotransformer based 12-pulse AC-DC converters feeding vector controlled induction motor drives (VCIMD) for improving the power quality at the point of common coupling (PCC) without using a Zero-Sequence-Blocking-Transformer (ZSBT). The proposed 24-pulse AC-DC converter is based on the principle of DC ripple re-injection technique for pulse multiplication and harmonic mitigation. The design of the autotransformer is carried out for the proposed AC-DC converter and the effect of load variation on VCIMD is also studied to demonstrate the effectiveness of the proposed AC-DC converter. Test results from a laboratory developed prototype, along with simulated results, are presented to validate the design and model of the proposed 24-pulse AC-DC converter.

Characteristics Evaluation of a Zoysiagrass Line '232'in the Tissue Culture and Field (종자 다수확계통'232'의 조직배양 및 포장에서의 특성 평가)

  • 이재필;김종보;임성희;주영규;김두환
    • Asian Journal of Turfgrass Science
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    • v.11 no.4
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    • pp.321-326
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    • 1997
  • A high seed yield '232' was evaluated for morphological characteristics and tissue culture re-sponse. The effect of mowing and urea application on coverage in '232' was also studied and the results were as follows ;1.'232' produced high seed yield than any other lines, but its other characteristics such as coverage, establishment rate, stolon length, stolon number and colour change were not good. 2.Callus induction of '232'(52.9%) was relatively high, and higher than that of Z. sinica(49.0%). However, embryogenic callus formation of '232' was not as good as that of Z. japonica and Z. sinica. 3.Coverage of '232' was very much enhanced by mowing on July 18, but not at all by mowing on May 29 and September 4. 4.Urea application did not increase the coverage in '232',Therefore, it can be used as a breeding material rather than direct use.

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Re-array of Piezoelectric Ceramic Grains by Electromagnetic Induced Thermal Radiation (전자기유도 열복사 영향 압전세라믹 입자 재배열 연구)

  • Hwang, InJoo;Shin, Dong Chul;Kim, Young Bae;Kim, Dae Weon
    • Journal of the Korean Society for Heat Treatment
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    • v.35 no.2
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    • pp.82-87
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    • 2022
  • The PZT piezoelectric ceramic on the copper alloy plate shows a extraordinary pattern resulted from the electromagnetic and thermal radiation induced by copper coil. The Eddy current or magnetic field by the polarization of PZT grains contained Pb, Zr, Ti with oxide is performed to show the change of array pattern at piezoelectric grains, especially wave-shaped or wrinkled configuration along with lines of electromagnetic field are becoming larger than before while applying the coil induction.

Effects of Ginseng Saponins on the Induction of Differentiation in Mammary Epithelial Cells and Mammary tumor Cells (홍삼 사포닌에 의한 유선상피 및 유선암세포의 분화 유도 효과 연구)

  • 오미숙;백기주;전성실;김규원;최강주;김남득
    • Journal of Ginseng Research
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    • v.24 no.4
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    • pp.188-195
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    • 2000
  • Using Ginseng saponins (crude saponin and total saponin) and ginsenoside Rbl Rb2, Rc, Rd, Re, Rhl, and Rh2 in this study, we have examined the effects of the compounds on the induction of differentiation in normal rat mammary epithelial cells and 7,12-dimethylbenz[a]anthracene (DMBA)-induced mammary tumor cells in culture. When normal rat mammary organoids were cultured in 100-mm culture plates in the presence or absence of ginseng saponins, there were four different cell colonies after two weeks in culture: cobble stone, spindle, honey comb, and senescence type colonies. Ginseng saponins showed different effects on the development of each colonies. Scrape-loading dye transfer tech-nique was performed to measure the effects of total saponin, Rhl, and Rh2 on intercellular junctional communication. Intercellular communication was not observed at short cultilral time, e.g., four or seven days, but when it cultured it up to two weeks, cell to cell communication was observed in saponin-treated cells. Reconstituted basement membrane, Matrigel, supported the growth and development several different multicellular structures from normal mammary organoids (e.g., ductal, webbed, stellate, and squamous colonies) or DMBA-induced mammary tumor (e.g., alveolar unit, foamy alveolar unit, squamous metaplasia, lobule-ductal, stellate, and webbed colony). In ginseng saponin-treated groups, webbed colonies were more and squamous colonies were less than control group. Moreover, the ductal colonies, marker tructure of well-differentiate mammary epithelial cells, were developed more in saponin-treated group than in control group. In conclusion, ginseng saponins affected on the differentiation of normal rat mammary epithelial cells and DMBA-induced mammary tumor cells in culture.

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High-level Production of Recombinant Human IFN-$\alpha2a$ with Co-expression of $tRNA^{Arg(AFF/AGA)}$ in High-cell-density Cultures of Escherichia coli

  • Shin, Chul-Soo;Hong, Min-Seon;Shin, Hang-Chel;Lee, Jeewon
    • Biotechnology and Bioprocess Engineering:BBE
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    • v.6 no.4
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    • pp.301-305
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    • 2001
  • The co-expression of the arg U gene in a double-vector expression system of recombi-nant Escherichia coli BL22(DE3)[pET-IEN2a+pAC-argU] significantly enhanced the production level of reconminant human interferon -$\alpha$2a(rhIFN-$\alpha$2a) in high cell density cultures, compared to a recombinant E. coli culture containing only the single expression vector, pET-IEN2a. The dry cell mass concentration increased to almost 100 g/L, and more than 4 g/L of rhIFN-$\alpha$2a was accumu-lated in the culture broth. Evidently, the synthesis of rhIFN-$\alpha$2a was strongly dependent on the pre-induction growtih rate and more efficient at a higher specific growth rate. The additional sup-ply of tRN $A^{Arg(AGG/AGA)}$ enhanced the expression level of the rhIFN-$\alpha$2a gene in the early stage of the post-induction phase, yet thereafter the specific production rate of rhIFN-$\alpha$2a rapidly de-creased due to severe segregational instability of plasmid vector pET-IEN2a. It would appear that the plasmid instability with only occurred to pET-IEN2a in the double vector system, was re-lated to the effect of translational stress due to the over expression of rhIFN-$\alpha$2a.

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Induction of CEA-specific Cytotoxic T Lymphocytes by Murine Dendritic Cells Expressing CEA (CEA 발현 수지상 세포를 이용한 CEA 특이 살해 T 세포의 유도)

  • Won, Eun-Ha;Kim, Chang-Hyun;Park, Mi-Young;Cho, Hyun-Il;Oh, Seong-Taek;Hong, Yong-Kil;Kim, Tai-Gyu
    • IMMUNE NETWORK
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    • v.3 no.4
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    • pp.295-301
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    • 2003
  • Background: Carcinoembryonic antigen (CEA) is well-known soluble tumor marker frequently detectable in peripheral blood of carcinoma patients and considered as good target for antigen-specific immunotherapy. In this study, we used a replication-deficient adenovirus containing CEA to study CTL induction in vitro after adenovirus-mediated gene transfer into DC. Methods: DC were obtained from mouse bone marrow and cultured with IL-4 and GM-CSF. For measuring CTL activity, splenocytes were harvested from the mice, which were immunized with DC that had been infected AdV-CEA or pulsed with CEA peptide. Untreated DC was used as a control. Splenocytes were re-stimulated in vitro with DC pulsed with CEA peptide for 7 days and CTL activity with CEA peptide-pulsed EL-4 cells were assessed in a standard $^{51}Cr$-release assay. The frequencies of antigen-specific cytokine-secreting T cell were determined with $mIFN-{\gamma}$ELISPOT. Results: DC infected with recombinant adenovirus expressing CEA induced CEA-specific CTL responses in vivo. Splenocyte induced from mice immunized with AdV-CEA-infected DC increase in the number of $IFN-{\gamma}$ secreting T cells compared with those from mice immunized with CEA peptide-pulsed DC. Conclusion: These results suggested that DC infected with recombinant adenovirus has advantages over other forms of vaccination and could provide an alternative approach vaccination therapies.

Concurrent Cisplatin and Radiotherapy in Refractory Patients to Induction Chemotherapy and Recurrent Head and Neck Cancer (유도항암요법에 반응치 않는 환자와 재발한 두경부암환자에서 Cisplatin과 방사선 동시치료)

  • Kim Hoon-Kyo;Kang Jin-Hyoung;Lee Kyung-Sik;Kim Dong-Jip;Chang Hong-Suk;Yoon Sei-Chul;Cho Seung-Ho;Sub Byung-Do
    • Korean Journal of Head & Neck Oncology
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    • v.8 no.1
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    • pp.21-24
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    • 1992
  • In patients with locally advanced head and neck cancers who do not respond to induction chemotherapy and who have locoregional recurrence after local treatment subsequent radiotherapy alone does not have any additative effect. The theoretical rationale and promising clinical response of concurrent chemoradiotherapy in patients with the head and neck cancers have been recently conducted Ten patients(9 stage IV, q stage III) were treated with concurrent chemoradiotherapy(radiotherapy start from day 1 of chemotherapy; cisplatin $100mg/m^2$ intravenously every 3 weeks for $3{\sim}4$ cycles on day 1.22 and 43..). Four patients achieved complete response(CR) and overall response rate was 80% (8/10). The major toxicities we re leukopenia (90%), nausea/vomiting(80%), stomatitis(80%) and peripheral neuropathy(30%). Most of these side effects were mild to moderate and reversible.

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Comparison of cytokine genes related with immune responses in canine macrophages using different culture models after infection with Brucella canis

  • Park, Woo Bin;Kim, Suji;Shim, Soojin;Yoo, Han Sang
    • Journal of Preventive Veterinary Medicine
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    • v.43 no.4
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    • pp.214-220
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    • 2019
  • Although canine brucellosis has been known to be an important re-emerging zoonosis, the pathophysiological mechanisms of Brucella canis infection remains clues to be solved. Different culture models, single and co-culture models, were constructed with canine epithelial cells, D17 and macrophage, DH82 to investigate the induction of immune responses in in vivo B. canis infection. Expression of genes related with induction of immune responses, Th1, Th2 and Th17, was compared in the two different models after the bacterial infection. In this study, expression of cytokine genes, IL-1β, IL-5, IL-6, IL-10, IL-23, and TNF-α was quantified in the DH82 at different time points using RT-qPCR in the two different culture systems after the infection. Cytokine genes related with Th1, IL-1β and TNF-α and Th17, IL-6 and IL-23 were expressed with time-dependent manners in the both systems (p<0.05). However, increase of Th2-related cytokine genes expression was not detectable in the both systems by comparison with control. The expression of Th1 and Th17 related cytokine genes was earlier in single cell culture than those in co-culture model (p<0.05). In general, amounts of the expressed genes were shown higher in single cell model than those in co-culture models. This study indicate that Th1 and Th17-associated immune responses are central to B. canis infection in dogs. In addition, it suggests a specific role of epithelial cells in the B. canis infection in vivo, which should resolved in the further study.

Antioxidant Activity and Neuroprotective Effect of Psoralea corylifolia Linne Extracts (파고지 (Psoralea corylifolia Linne) 추출물의 항산화 작용에 의한 신경세포 보호효과)

  • Yoon, Mi-Young;Lee, Bo-Bae;Kim, Ju-Young;Kim, Yong-Seong;Park, Eun-Ju;Lee, Seung-Cheol;Park, Hae-Ryong
    • Korean Journal of Pharmacognosy
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    • v.38 no.1
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    • pp.84-89
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    • 2007
  • The present study describes the preliminary evaluation of the antioxidant activities and the neuroprotective effect of methanolic extracts from Psoralea corylifolia Linne (PCE). The antioxidant activities and neuroprotective effect of the PCE were evaluated by total phenolic contents (TPC), DPPH radical scavenging activity (RSA), reducing power (RP), MTT reduction assay, and LDH release assay. TPC, DPPH RSA, and RP of the extract at concentration of 100 ${\mu}g$ was 125.93 ${\mu}g$, 63.81%, 0.138, respectively, and those were concentration dependent. The treatment of PC12 and N18-RE-105 cells with various PCE concentrations under $H_2O_2$ resulted in the induction of protective effect in a dose-dependent manner, as determined by the results of an MTT reduction assay and LDH release assay. Therefore, these results suggest that PCE could be a new potential candidate as an antioxidant against neuronal diseases.