• 제목/요약/키워드: Single cell analysis/methods

검색결과 202건 처리시간 0.025초

제 IV병기 비소세포폐암의 예후인자 (Prognostic Factors for Survival in Patients with Stage IV non-small Cell Lung Cancer)

  • 김명훈;박희선;강현모;장필순;이연선;안진영;권선중;정성수;김주옥;김선영
    • Tuberculosis and Respiratory Diseases
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    • 제53권4호
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    • pp.379-388
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    • 2002
  • 연구배경 : 폐암 중 80%를 차지하는 비소세포폐암은 발견 당시부터 전이성 병변이 있는 IV기로 진단되는 경우가 적지 않다. 그러나 그동안 IV병기 비소세포폐암의 예후인자에 대한 조사는 충분하지 않았었다. 이에 저자들은 IV병기 비소세포폐암으로 진단을 받은 환자들을 대상으로 생존기간에 영향을 미치는 예후인자의 분석과 M1으로 평가되는 전이 장기에 따른 생존기간의 차이를 조사하고자 하였다. 방 법 : 1997년 1월부터 2000년 12월까지 충남대학교병원에 내원해서 병리조직학적으로 IV병기 비소세포폐 암으로 진단을 받은 151명을 대상으로 하였고, 의무기록을 통한 후향적인 방법으로 분석하였다. 결 과 : 1) 생존기간에 대한 단변수 분석 결과 연령, 신체 활동도, 혈청 알부민 농도, 체중감소, $FEV_1$, 전신 항암화학요법 유무, 전이 장기 개수는 생존기간에 매우 유의한 (p<0.01) 예후인자들이었으며, 혈청 LDH 농도 역시 유의한 예후인자이었다 (p<0.05). 2) 전이 장기에 따른 생존율의 단변수 분석에서 뇌전이, 간전이가 있는 경우가 그 외에 다른 장기에 전이가 있는 경우보다 생존율이 낮았다 (p<0.05). 3) 단독으로 전이된 장기에 따른 생존율의 분석에서 폐전이만 있는 경우가 폐와 다른 장기의 전이가 동시에 있는 경우나 폐 이외의 장기에 전이가 있는 경우보다 생존율이 높았다 (p=0.000). 4) 생존기간에 대한 다변수 분석 결과 ECOG (상대위험도=2.700, p=0.000), 전신 항암화학요법 유무 (상대위험도=1.944, p=0.010), 혈청 LDH 농도(상대위험도=1.819, p=0.021) 그리고 $FEV_1$ (상대위험도=1.774, p=0.022)이 생존기간에 영향을 미치는 유의한 독립적인 예후인자였다. 결 론 : 본 연구에서 IV병기 비소세포폐암 중 폐에 단독으로 전이가 있는 경우가 다른 장기에 전이가 있는 경우보다 비교적 생존율이 높았고, 뇌전이, 간전이가 있는 경우 생존율이 낮았다. 따라서 원격전이로 동일하게 평가되고 있는 M1 병기라도 전이 장기의 종류에 따라 생존기간의 차이가 있을 수 있으므로 M1 병기 시스템에서 생존율에 대하여 재해석이 고려되어야겠다. 그러나 이번 연구는 후향적 분석이며 대상환자수가 많지 않아서 이 결과에 대한 확인을 위해서 이후에 많은 수의 환자를 대상으로 전향적인 연구가 필요하다고 생각된다.

Prognosis for Pneumonic-Type Invasive Mucinous Adenocarcinoma in a Single Lobe on CT: Is It Reasonable to Designate It as Clinical T3?

  • Wooil Kim;Sang Min Lee;Jung Bok Lee;Joon Beom Seo;Hong Kwan Kim;Jhingook Kim;Ho Yun Lee
    • Korean Journal of Radiology
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    • 제23권3호
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    • pp.370-380
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    • 2022
  • Objective: To compare pneumonic-type invasive mucinous adenocarcinoma (pIMA) confined to a single lobe with clinical T2, T3, and T4 stage lung cancer without pathological node metastasis regarding survival after curative surgery and to identify prognostic factors for pIMA. Materials and Methods: From January 2010 to December 2017, 41 patients (15 male; mean age ± standard deviation, 66.0 ± 9.9 years) who had pIMA confined to a single lobe on computed tomography (CT) and underwent curative surgery were identified in two tertiary hospitals. Three hundred and thirteen patients (222 male; 66.3 ± 9.4 years) who had non-small cell lung cancer (NSCLC) without pathological node metastasis and underwent curative surgery in one participating institution formed a reference group. Relapse-free survival (RFS) and overall survival (OS) were calculated using the Kaplan-Meier method. Cox proportional hazard regression analysis was performed to identify factors associated with the survival of patients with pIMA. Results: The 5-year RFS and OS rates in patients with pIMA were 33.1% and 56.0%, respectively, compared with 74.3% and 91%, 64.3% and 71.8%, and 46.9% and 49.5% for patients with clinical stage T2, T3, and T4 NSCLC in the reference group, respectively. The RFS of patients with pIMA was comparable to that of patients with clinical stage T4 NSCLC and significantly worse than that of patients with clinical stage T3 NSCLC (p = 0.012). The differences in OS between patients with pIMA and those with clinical stage T3 or T4 NSCLC were not significant (p = 0.11 and p = 0.37, respectively). In patients with pIMA, the presence of separate nodules was a significant factor associated with poor RFS and OS {unadjusted hazard ratio (HR), 4.66 (95% confidence interval [CI], 1.95-11.11), p < 0.001 for RFS; adjusted HR, 4.53 (95% CI, 1.59-12.89), p = 0.005 for OS}. Conclusion: The RFS of patients with pIMA was comparable to that of patients with clinical stage T4 lung cancer. Separate nodules on CT were associated with poor RFS and OS in patients with pIMA.

CD4+, IL17 and Foxp3 Expression in Different pTNM Stages of Operable Non-small Cell Lung Cancer and Effects on Disease Prognosis

  • Zhang, Guo-Qing;Han, Feng;Fang, Xin-Zhi;Ma, Xiao-Mei
    • Asian Pacific Journal of Cancer Prevention
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    • 제13권8호
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    • pp.3955-3960
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    • 2012
  • Objective: To investigate the effects of $CD4^+$, IL17 and Foxp3 expression on prognosis of operable non-small cell lung cancer (NSCLC) with different pTNM stages. Methods: Expression of $CD4^+$, IL17 and Foxp3 in 102 cases of NSCLC tissues and adjacent cancer tissues was detected by immunohistochemistry and associations with prognosis with different pTNM stages were analyzed. The Chi-square test was used to compare count data. Survival differences were evaluated by Kaplan-Meier single factor analysis and the COX regression model was used to analyze the relationship between influential factors and the disease prognosis. The significance level was ${\alpha}$=0.05. Results: Expression of CD4, IL-17 and Foxp3 significantly varied in different pTNM stages of NSCLC tissues (P < 0.05). The same was true for CD4 expression (P < 0.05). The median survival time (MST) in the positive CD4 expression group was evidently higher than that in the negative group (25.8/23.9 months). Compared with stage III, the MST difference of stages I and II in the positive CD4 expression group were statistically significant (P < 0.05). The MST in positive IL-17 and Foxp3 expression groups was obviously lower than that in the corresponding negative group (P < 0.05) (25.6/35.1 months and 24/35.3 months, respectively). There was a significant difference of MST between any two of three stages of positive IL-17 expression group (P < 0.05), and it was the same with positive Foxp3 expression group. TNM stage, negative CD4 expression, and positive IL-17 and Foxp3 expression were the main risk factors for the prognosis of NSCLC. Conclusion: Surgical prognosis of NSCLC can be better assessed by the combination of clinical staging and expression of IL17 and Foxp3.

Gefitinib Alone or with Concomitant Whole Brain Radiotherapy for Patients with Brain Metastasis from Non-small-cell Lung Cancer: A Retrospective Study

  • Zeng, Yin-Duo;Zhang, Li;Liao, Hai;Liang, Ying;Xu, Fei;Liu, Jun-Ling;Dinglin, Xiao-Xiao;Chen, Li-Kun
    • Asian Pacific Journal of Cancer Prevention
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    • 제13권3호
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    • pp.909-914
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    • 2012
  • Background: Gefitinib, a tyrosine kinase inhibitor (TKI) of epidermal growth factor receptor (EGFR), is used both as a single drug and concurrently with whole brain radiotherapy (WBRT) the standard treatment for brain metastases (BM), and is reported to be effective in a few small studies of patients with BM from non-small-cell lung cancer (NSCLC). However, no study has compared the two treatment modalities. This retrospective analysis was conducted to compare the efficacy of gefitinib alone with gefitinib plus concomitant WBRT in treatment of BM from NSCLC. Methods: We retrospectively reviewed 90 patients with BM from NSCLC who received gefitinib alone (250mg/day, gefitinib group) or with concomitant WBRT (40Gy/20f/4w, gefitinib-WBRT group) between September 2005 and September 2009 at Sun Yat-Sen University Cancer Center. Forty-five patients were in each group. Results: The objective response rate of BM was significantly higher in gefitinib-WBRT group (64.4%) compared with gefitinib group (26.7%, P<0.001). The disease control rate of BM was 71.1% in gefitinib-WBRT group and 42.2% in gefitinib group (P=0.006). The median time to progression of BM was 10.6 months in gefitinib-WBRT group and 6.57 months in gefitinib group (P<0.001). The median overall survival(OS) of gefitinib-WBRT and gefitinib alone group was 23.40 months and 14.83 months, respectively (HR, 0.432, P=0.002). Conclusion: Gefitinib plus concomitant WBRT had higher response rate of BM and significant improvement in OS compared with gefitinib alone in treatment of BM from NSCLC.

Neural Growth Factor Stimulates Proliferation of Spinal Cord Derived-Neural Precursor/Stem Cells

  • Han, Youngmin;Kim, Kyoung-Tae
    • Journal of Korean Neurosurgical Society
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    • 제59권5호
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    • pp.437-441
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    • 2016
  • Objective : Recently, regenerative therapies have been used in clinical trials (heart, cartilage, skeletal). We don't make use of these treatments to spinal cord injury (SCI) patients yet, but regenerative therapies are rising interest in recent study about SCI. Neural precursor/stem cell (NPSC) proliferation is a significant event in functional recovery of the central nervous system (CNS). However, brain NPSCs and spinal cord NPSCs (SC-NPSCs) have many differences including gene expression and proliferation. The purpose of this study was to investigate the influence of neural growth factor (NGF) on the proliferation of SC-NPSCs. Methods : NPSCs ($2{\times}10^4$) were suspended in $100{\mu}L$ of neurobasal medium containing NGF-7S (Sigma-Aldrich) and cultured in a 96-well plate for 12 days. NPSC proliferation was analyzed five times for either concentration of NGF (0.02 and 2 ng/mL). Sixteen rats after SCI were randomly allocated into two groups. In group 1 (SCI-vehicle group, n=8), animals received 1.0 mL of the saline vehicle solution. In group 2 (SCI-NGF group, n=8), the animals received single doses of NGF (Sigma-Aldrich). A dose of 0.02 ng/mL of NGF or normal saline as a vehicle control was intra-thecally injected daily at 24 hour intervals for 7 days. For Immunohistochemistry analysis, rats were sacrificed after one week and the spinal cords were obtained. Results : The elevation of cell proliferation with 0.02 ng/mL NGF was significant (p<0.05) but was not significant for 2 ng/mL NGF. The optical density was increased in the NGF 0.02 ng/mL group compared to the control group and NGF 2 ng/mL groups. The density of nestin in the SCI-NGF group was significantly increased over the SCI-vehicle group (p<0.05). High power microscopy revealed that the density of nestin in the SCI-NGF group was significantly increased over the SCI-vehicle group. Conclusion : SC-NPSC proliferation is an important pathway in the functional recovery of SCI. NGF enhances SC-NPSC proliferation in vitro and in vivo. NGF may be a useful option for treatment of SCI patients pending further studies to verify the clinical applicability.

인체 암세포주에서 방사선감수성의 지표간의 상호관계 (Correlation Between the Parameters of Radiosensitivity in Human Cancer Cell Lines)

  • 박우윤;김원동;민경수
    • Radiation Oncology Journal
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    • 제16권2호
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    • pp.99-106
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    • 1998
  • 목적 : 임상에서 발생빈도가 높은 위선암, 폐선암, 망막세포종, 자궁경부 편평상피암의 4가지 인 체암세포주(MKN-45, PC-14, Y-79, HeL)를 이용하여 방사선조사후 세포생존분획 및 세포생존곡선의 모양을 결정하는 지표를 구하고 방사선조사후 손상 회복정도를 측정하여 이들 여러 지표간의 상관관계 여부를 구명하기 위하여 본실험을 시행하였다. 대상 및 방법 :각 세포주의 방사선감수성을 보기 위하여 1, 2, 3, 5, 7 및 10Gy의 방사선을 1 회 조사하였고 방사선조사후 준치사손상 회복정도를 보기 위하여 5Gy씩 2회의 방사선조사를 0, 1, 2, 3, 4, 6 및 24시간 간격으로 시행하였다. 세포의 생존분획은 $Sperman-K\"{a}rbor$ 방법으로 세포집락형성능력을 측정하여 산출하였으며 생존곡선의 수학적 분석은 linear-quadratic(LQ), multitarget-single hit(MS) 모형과 mean inactivation $dose(\v{D})$를 이용하였다. 결과 : 방사선조사후의 세포생존 실험결과 2Gy에서의 세포생존분획(SF2)은 0.174에서 0.85까지 다양하게 나타났으며 Y-79는 유의하게 낮은 SF2를, PC-14는 높은 SF2를 나타내었다(p<0.05, t-test). LQ model로 분석한 방사선 세포생존곡선의 분석결과 Y-79, MKN-45, HeLa, PC-14에서 ${\alpha}$가 각각 0.603, 0.355, 0.275, 0.102이었고 ${\beta}$는 각각 0.005, 0.016, 0.025, 0.027이었다. MS model로 분석한 결과는 Y-79, MKN-45, HeLa, PC-14에서 Do가 각각 1.59, 1.84, 1.88, 2.52였고 n은 0.97, 1.46, 1.52, 1.69를 보였다. 한편 Gauss-Laguerre방법으로 계산한 $\v{D}$는 Y-79, MKN-45, HeLa, PC-14에서 각각 1.62, 2.37, 2.61, 3.95였다. SF2가 감소함에 따라 ${\alpha}$값은 증가하였고 Do, $\v{D}$값은 감소하였으며 이들간의 Pearson 상관계수는 각각 0.953, 0.993, 0.999였다. (p<0.05). 분할조사에 의한 준치사손상 회복정도는 약 4시간 내외에 포화상태에 도달하였으며 포화상태의 recovery ratio(RR)는 2에서 3.79 사이였다. RR은 방사선감수성의 지표인 SF2, ${\alpha}$, ${\beta}$, Do, $\v{D}$과 통계학적으로 유의한 상관관계를 나타내지 않았다. 결론 : 본 연구의 결과 네가지 인체상피암세포주의 내재적 발사선감수성은 서로 상이하였으며 Y-79가 가장 민감하였고, MKN-45와 HeLa는 각각 중등도의 방사선감수성을 나타냈으며 PC-14는 방사선감수성이 가장 낮았다. 이와같은 감수성의 차이는 SF2, ${\alpha}$, Do와 $\v{D}$의 차이로 나타났으며 띠들간에는 밀접한 상관관계를 나타내었다. 방사선에 의한 준치사손상 회복력은 MKN-45와 HeLa에서 높게 나타났고 회복력과 방사선감수성과는 무관하였다. 각 암세포주에 따르는 이와같은 지표들은 향후 방사선치료 효과를 높이기 위한 방사선생물학 실험의 기초 자료로서 이용되어 질 수 있을 것이다.

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Feasibility and Efficacy of Concurrent Chemoradiotherapy in Elderly Patients with Esophageal Squamous Cell Carcinoma: a Respective Study of 116 Cases from a Single Institution

  • Li, Xue;Zhao, Lu-Jun;Liu, Ning-Bo;Zhang, Wen-Cheng;Pang, Qing-Song;Wang, Ping;Yuan, Zhi-Yong
    • Asian Pacific Journal of Cancer Prevention
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    • 제16권4호
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    • pp.1463-1469
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    • 2015
  • Background: To evaluate the safety and efficacy of combined chemoradiotherapy or radiotherapy alone in elderly patients with esophageal carcinoma to identify the best method of treatment. Materials and Methods: One hundred and sixteen patients with esophageal carcinoma aged 70 and older who received definitive radiotherapy or chemoradiotherapy entered the study. Overall survival (OS), disease-free survival (DFS) and treatment-related toxicities were assessed. Results: The median OS of the overall population was 17.9 months. For patients treated with cCRT, sCRT and radiotherapy alone, the median OS was 22.3 months, 18.0 months and 12.4 months respectively(P=0.044). Median OS for patients treated with radiotherapy dose ${\geq}60Gy$ and <60Gy was 20.2 months and 10.9 months respectively (p=0.017). By univariate analysis, Chemoradiotherapy (include cCRT and sCRT) and radiotherapy dose ${\geq}60Gy$ were found to achieve higher survival rates compared with radiotherapy alone and radiotherapy dose <60Gy (P=0.015, P=0.017). By multivariate analysis, chemoradiotherapy (HR=1.645, P=0.022) and radiotherapy dose ${\geq}60Gy$ (HR=1.642, P=0.025) were identified as independent prognostic factors of OS. Conclusions: Definitive concurrent chemoradiotherapy could be considered as a feasible and effective treatment in esophageal carcinoma patients aged 70 and older. Radiotherapy dose 60Gy is an effective treatment option compared with standard dose radiotherapy, while higher doses are not beneficial to improve survival.

감염 근관에서 혐기성 배양법과 간접 면역 형광법 및 DNA 프로브법에 의한 Porphyromonas endodontalis의 검출에 관한 비교 연구 (COMPARATIVE STUDY ON THE DETECTION OF PORPHYROMONAS ENDODONTALIS BY ANAEROBIC CULTURE, IIF AND DNA PROBE METHOD IN INFECTED ROOT CANALS)

  • 김민겸;윤수한;정종평
    • Restorative Dentistry and Endodontics
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    • 제21권1호
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    • pp.1-18
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    • 1996
  • There are many advantages when using IIF and DNA probe methods over anaerobic culture method in that they are time-and effort-saving, more precise and more sensitive. Furthermore, in IIF and DNA probe methods, the detection is possible only with small amount of bacteria, the quantitative analysis is possible, and the cell viability is not necessary. The purpose of this study is to observe the incidence of P.endodontalis by carrying out anaerobic culture, IIF and colony lift using DNA probe method respectively, and to compare these 3 methods in terms of effectiveness and sensitivity in order to identify the most effective detection method. 30 teeth with at least one clinical symptoms, with single canal, and with pulp necrosis were sampled. For sampling bacteria, access cavity was prepared after disinfecting tooth and its surroundings. Then the paper point was inserted up to the periapical area, leave there for a while, and finally it was placed into PRAS Ringer's sol. and PBS sol. In anaerobic culture method, P.endodontalis was identified by biochemical tests after subculturing black and brown colonies which were produced after 7 days of incubation on BAP and Brucella BAP in anaerobic chamber. To identify P.endodontalis in IIF method, species-specific polyclonal rabbit-antisera of P.endodontalis(ATCC 35406) was reacted with sampled PBS sol. dispensed onto glass slide, and then P.endodontalis was examined by phase contrast microscopy after incubating with Goat anti-rabbit lgG conjugated to Fluorescein isothiocyanate. For colony lift using DNA probe method, membranes were laid over colonies on the surface of BAP and were hybridized with cloned DNA probe of P.endodontalis. The existence of P.endodontalis was then identified by the methods of chemiluminescent detection and color metric detection. Black colony was found in 11 teeth out of 30 teeth and P.endodontalis was detected in 6 teeth (20 %) by anaerobic culture method, 16 teeth (53 %) by IIF method, and 7 teeth (23 %) by DNA probe method. IIF method is significantly better in detecting P.endodontalis than DNA probe method and anaerobic culture method. There was no significant differences between DNA probe method and anaerobic culture method. There was significant correlation between the formation of black colony and the existence of P.endodontalis. The probability of detecting P.endodontalis when black colony being present is 2.89 times higher than when not being present. There was significant relationship between the foul odor of clinical symptoms and P.endodontalis. The sensitivity of existing P.endodontalis when foul odor being present was 93.75 %, while the specificity of not existing P.endodontalis when foul odor not being present was 28.57 %. These results suggested that the probes of P.endodontalis will be used to decide the method and prognosis in endodontic treatments.

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BCR/ABL mRNA Targeting Small Interfering RNA Effects on Proliferation and Apoptosis in Chronic Myeloid Leukemia

  • Zhu, Xi-Shan;Lin, Zi-Ying;Du, Jing;Cao, Guang-Xin;Liu, Gang
    • Asian Pacific Journal of Cancer Prevention
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    • 제15권12호
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    • pp.4773-4780
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    • 2014
  • Background: To investigate the effects of small interference RNA (siRNA) targeting BCR/ABL mRNA on proliferation and apoptosis in the K562 human chronic myeloid leukemia (CML) cell line and to provide a theoretical rationale and experimental evidence for its potential clinical application for anti-CML treatment. Materials and Methods: The gene sequence for BCR/ABL mRNA was found from the GeneBank. The target gene site on the BCR/ABL mRNA were selected according to Max-Planck-Institute (MPI) and rational siRNA design rules, the secondary structure of the candidate targeted mRNA was predicted, the relevant thermodynamic parameters were analyzed, and the targeted gene sequences were compared with BLAST to eliminate any sequences with significant homology. Inhibition of proliferation was evaluated by MTT assay and colony-formation inhibiting test. Apoptosis was determined by flow cytometry (FCM) and the morphology of apoptotic cells was identified by Giemsa-Wright staining. Western blotting was used to analyze the expression of BCR/ABL fusion protein in K562 cells after siRNA treatment. Results: The mRNA local secondary structure calculated by RNA structure software, and the optimal design of specific siRNA were contributed by bioinformatics rules. Five sequences of BCR/ABL siRNAs were designed and synthesized in vitro. Three sequences, siRNA1384, siRNA1276 and siRNA1786, which showed the most effective inhibition of K562 cell growth, were identified among the five candidate siRNAs, with a cell proliferative inhibitory rate nearly 50% after exposure to 12.5nmol/L~50nmol/L siRNA1384 for 24,48 and 72 hours. The 50% inhibitory concentrations ($IC_{50}$) of siRNA1384, siRNA1276 and siRNA1786 for 24hours were 46.6 nmol/L, 59.3 nmol/L and 62.6 nmol/L, respectively, and 65.668 nmol/L, 76.6 nmol/L, 74.4 nmol/L for 72 hours. The colony-formation inhibiting test also indicated that, compared with control, cell growth of siRNA treated group was inhibited. FCM results showed that the rate of cell apoptosis increased 24 hours after transfecting siRNA. The results of annexinV/PI staining indicated that the rate of apoptosis imcreased (1.53%, 15.3%, 64.5%, 57.5% and 21.5%) following treamtne with siRNAs (siRNA34, siRNA372, siRNA1384, siRNA1276 and siRNA1786). Morphological analysis showed td typical morphologic changes of apoptosis such as shrunken, fragmentation nucleus as well as "apoptotic bodies" after K562 cell exposure to siRNA. Western blot analysis showed that BCR/ABL protein was reduced sharply after a single dose of 50nmol/L siRNA transfection. Conclusions: Proliferation of K562 cells was remarkbly inhibited by siRNAs (siRNA1384, siRNA1276 and siRNA1786) in a concentration-dependent manner in vitro, with effective induction of apoptosis at a concentration of 50 nmol/L. One anti-leukemia mechanism in K562 cells appeared that BCR/ABL targeted protein was highly down-regulated. The siRNAs (siRNA1384, siRNA1276 and siRNA1786) may prove valuable in the treatment of CML.

Electrodeposition of Silicon in Ionic Liquid of [bmpy]$Tf_2N$

  • 박제식;이철경
    • 한국재료학회:학술대회논문집
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    • 한국재료학회 2011년도 추계학술발표대회
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    • pp.30.1-30.1
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    • 2011
  • Silicon is one of useful materials in various industry such as semiconductor, solar cell, and secondary battery. The metallic silicon produces generally melting process for ingot type or chemical vapor deposition (CVD) for thin film type. However, these methods have disadvantages of high cost, complicated process, and consumption of much energy. Electrodeposition has been known as a powerful synthesis method for obtaining metallic species by relatively simple operation with current and voltage control. Unfortunately, the electrodeposition of the silicon is impossible in aqueous electrolyte solution due to its low oxidation-reduction equilibrium potential. Ionic liquids are simply defined as ionic melts with a melting point below $100^{\circ}C$. Characteristics of the ionic liquids are high ionic conductivities, low vapour pressures, chemical stability, and wide electrochemical windows. The ionic liquids enable the electrochemically active elements, such as silicon, titanium, and aluminum, to be reduced to their metallic states without vigorous hydrogen gas evolution. In this study, the electrodeposion of silicon has been investigated in ionic liquid of 1-butyl-3-methylpyrolidinium bis (trifluoromethylsulfonyl) imide ([bmpy]$Tf_2N$) saturated with $SiCl_4$ at room temperature. Also, the effect of electrode materials on the electrodeposition and morphological characteristics of the silicon electrodeposited were analyzed The silicon electrodeposited on gold substrate was composed of the metallic Si with single crystalline size between 100~200nm. The silicon content by XPS analysis was detected in 31.3 wt% and the others were oxygen, gold, and carbon. The oxygen was detected much in edge area of th electrode due to $SiO_2$ from a partial oxidation of the metallic Si.

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