• 제목/요약/키워드: Cell formation

검색결과 4,024건 처리시간 0.031초

Hemispherical Grain Silicon에 의한 정전용량 확보 및 공정조건 특성에 관한 연구 (A Study on Capacitance Enhancement by Hemispherical Grain Silicon and Process Condition Properties)

  • 정양희;정재영;이승희;강성준;이보희;유일현;최남섭
    • 한국정보통신학회논문지
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    • 제4권4호
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    • pp.809-815
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    • 2000
  • The box capacitor structure with HSG-Si described here reliably achieves a cell capacitance of 28fF with a cell area of a $0.4820\mum^2$ for 128Mbit DRAM. An HSG-Si formation technology with seeding method, which employs Si2H6 molecule irradiation and annealing, was applied for realizing 64Mbit and larger DRAMS. By using this technique, grain size controlled HSG-Si can be fabricated on in-situ phosphorous doped amorphous silicon electrodes. The HSG-Si fabrication technology achieves twice the storage capacitance with high reliability for the stacked capacitors.The box capacitor structure with HSG-Si described here reliably achieves a cell capacitance of 28fF with a cell area of a $0.4820\mum^2$ for 128Mbit DRAM. An HSG-Si formation technology with seeding method, which employs Si2H6 molecule irradiation and annealing, was applied for realizing 64Mbit and larger DRAMS. By using this technique, grain size controlled HSG-Si can be fabricated on in-situ phosphorous doped amorphous silicon electrodes. The HSG-Si fabrication technology achieves twice the storage capacitance with high reliability for the stacked capacitors.

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Hypericin, a Naphthodianthrone Derivative, Prevents Methylglyoxal-Induced Human Endothelial Cell Dysfunction

  • Do, Moon Ho;Kim, Sun Yeou
    • Biomolecules & Therapeutics
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    • 제25권2호
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    • pp.158-164
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    • 2017
  • Methylglyoxal (MGO) is a highly reactive metabolite of glucose which is known to cause damage and induce apoptosis in endothelial cells. Endothelial cell damage is implicated in the progression of diabetes-associated complications and atherosclerosis. Hypericin, a naphthodianthrone isolated from Hypericum perforatum L. (St. John's Wort), is a potent and selective inhibitor of protein kinase C and is reported to reduce neuropathic pain. In this work, we investigated the protective effect of hypericin on MGO-induced apoptosis in human umbilical vein endothelial cells (HUVECs). Hypericin showed significant anti-apoptotic activity in MGO-treated HUVECs. Pretreatment with hypericin significantly inhibited MGO-induced changes in cell morphology, cell death, and production of intracellular reactive oxygen species. Hypericin prevented MGO-induced apoptosis in HUVECs by increasing Bcl-2 expression and decreasing Bax expression. MGO was found to activate mitogen-activated protein kinases (MAPKs). Pretreatment with hypericin strongly inhibited the activation of MAPKs, including P38, JNK, and ERK1/2. Interestingly, hypericin also inhibited the formation of AGEs. These findings suggest that hypericin may be an effective regulator of MGO-induced apoptosis. In conclusion, hypericin downregulated the formation of AGEs and ameliorated MGO-induced dysfunction in human endothelial cells.

The Effects of Rotating Magnetic Field on Growth Rate, Cell Metabolic Activity and Biofilm Formation by Staphylococcus Aureus and Escherichia Coli

  • Fijalkowski, Karol;Nawrotek, Pawel;Struk, Magdalena;Kordas, Marian;Rakoczy, Rafal
    • Journal of Magnetics
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    • 제18권3호
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    • pp.289-296
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    • 2013
  • This work presents results of the study which concerns the influence of the rotating magnetic field (RMF) on the growth rate, cell metabolic activity and ability to form biofilms by E. coli and S. aureus. Liquid cultures of the bacteria were exposed to the RMF (RMF frequency f = 1-50 Hz, RMF magnetic induction B = 22-34 mT, time of exposure t = 60 min, temperature of incubation $37^{\circ}C$). The present study indicate the exposition to the RMF, as compared to the unexposed controls causing an increase in the growth dynamics, cell metabolic activities and percentage of biofilm-forming bacteria, in both S. aureus and E. coli cultures. It was also found that the stimulating effects of the RMF exposition enhanced with its increasing frequencies and magnetic inductions.

TSPAN12 Precedes Tumor Proliferation by Cell Cycle Control in Ovarian Cancer

  • Ji, Guohua;Liang, Hongbin;Wang, Falin;Wang, Nan;Fu, Songbin;Cui, Xiaobo
    • Molecules and Cells
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    • 제42권7호
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    • pp.557-567
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    • 2019
  • TSPAN12, a member of the tetraspanin family, has been highly connected with the pathogenesis of cancer. Its biological function, however, especially in ovarian cancer (OC), has not been well elucidated. In this study, The Cancer Genome Atlas (TCGA) dataset analysis revealed that upregulation of TSPAN12 gene expression was significantly correlated with patient survival, suggesting that TSPAN12 might be a potential prognostic marker for OC. Further exploration showed that TSPAN12 overexpression accelerated proliferation and colony formation of OVCAR3 and SKOV3 OC cells. Knockdown of TSPAN12 expression in A2780 and SKOV3 cells decreased both proliferation and colony formation. Western blot analysis showed that several cyclins and cyclin-dependent kinases (CDK) (e.g., Cyclin A2, Cyclin D1, Cyclin E2, CDK2, and CDK4) were significantly involved in the regulation of cell cycle downstream of TSPAN12. Moreover, TSPAN12 accelerated mitotic progression by controlling cell cycle. Thus, our data demonstrated that TSPAN12 could be a novel molecular target for the treatment of OC.

E-Beam evaporation을 이용한 전극 형성 공정이 결정질 실리콘 태양전지에 미치는 영향 분석 (Effect of Electrode Formation Process using E-beam Evaporation on Crystalline Silicon Solar Cell)

  • 최동진;박세진;신승현;이창현;배수현;강윤묵;이해석;김동환
    • Current Photovoltaic Research
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    • 제7권1호
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    • pp.15-20
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    • 2019
  • Most high-efficiency n-type silicon solar cells are based on the high quality surface passivation and ohmic contact between the emitter and the metal. Currently, various metalization methods such as screen printing using metal paste and physical vapor deposition are being used in forming electrodes of n-type silicon solar cell. In this paper, we analyzed the degradation factors induced by the front electrode formation process using e-beam evaporation of double passivation structure of p-type emitter and $Al_2O_3/SiN_x$ for high efficiency solar cell using n-type bulk silicon. In order to confirm the cause of the degradation, the passivation characteristics of each electrode region were determined through a quasi-steady-state photo-conductance (QSSPC).

복어(Takifugu obscurus) 균질액에 의한 MCF-7 인간 유방암세포 성장 억제 효과 (Suppression of MCF-7 Human Breast Cancer Cell Proliferation by Globefish Takifugu obscurus Homogenate)

  • 김정훈;김정호
    • 한국수산과학회지
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    • 제53권6호
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    • pp.878-885
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    • 2020
  • Previously, we reported that globefish Takifugu obscurus homogenate suppresses the growth of human colorectal cancer cells. To extend the applications of globefish homogenate, we investigated its cytotoxic effects on human breast cancer cells. To assess the effects of globefish homogenate on growth of MCF (Michigan Cancer Foundation)-7 human breast cancer cells, cell proliferation and colony formation assays were performed using the cell counting and Crystal Violet staining methods. The 50% inhibitory concentration (IC50) of globefish homogenate on MCF-7 cell proliferation was calculated from the sigmoidal dose-response curve. The colony formation assay demonstrated that MCF-7 cells treated with globefish homogenate formed up to 80% fewer colonies than control MCF-7 cells. Treatment with globefish homogenate markedly suppressed the growth of MCF-7 cells in a dose-dependent manner. The sensitivity of the cells to globefish homogenate was determined by calculating the IC50; in this case, the IC50 was 210 ㎍/mL. Furthermore, significant downregulation of Cyclin D1 expression, along with phospho-Akt and total Akt levels, was observed in MCF-7 cells treated with globefish homogenate. This study demonstrates that treatment with globefish homogenate inhibits the proliferation of MCF-7 human breast cancer cells by downregulating the expression of phosphor-Akt, total Akt, and Cyclin D1 proteins.

Efficacy of biological inhibitors in three-dimensional culture models of oral squamous cell carcinoma

  • Eun Kyoung Kim;Sook Moon;Myung-Jin Lee;Dokyeong Kim
    • International Journal of Oral Biology
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    • 제49권1호
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    • pp.18-25
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    • 2024
  • Despite advancements in therapeutic approaches, radiotherapy and cisplatin-based chemotherapy remain primary noninvasive treatments for patients with oral squamous cell carcinoma (OSCC). Moreover, the 5-year survival rate for patients with OSCC has remained almost unchanged for several decades, and many side effects of chemotherapy still exist. In this study, three-dimensional (3D) models of OSCC were established using fibroblasts, and the efficacy of various biological inhibitors was evaluated. A culture of epithelial cells with two types of fibroblasts (hTERT-hNOFs and cancer-associated fibroblasts) within a type I collagen matrix resulted in the formation of a continuous layer of tightly packed cells compared to models without fibroblasts. Furthermore, the effects of biological chemicals, including Y27632, latrunculin A, and verteporfin, on these models were investigated. The stratified formation of the epithelial layer and invasion in OSCC 3D-culture models were effectively inhibited by verteporfin, whereas invasion was weakly inhibited by Y27632 and latrunculin. Collectively, the developed OSCC 3D-culture models established with fibroblasts demonstrated the potential for drug screening, with verteporfin showing promising efficacy.