• BMB Reports
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• v.50 no.9
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• pp.437-444
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• 2017

Different types of eukaryotic cells may adopt seemingly distinct modes of directional cell migration. However, several core aspects are regarded common whether the movement is either ameoboidal or mesenchymal. The region of cells facing the attractive signal is often termed leading edge where lamellipodial structures dominates and the other end of the cell called rear end is often mediating cytoskeletal F-actin contraction involving Myosin-II. Dynamic remodeling of cell-to-matrix adhesion involving integrin is also evident in many types of migrating cells. All these three aspects of cell migration are significantly affected by signaling networks of TorC2, TorC1, and PP2A/B56. Here we review the current views of the mechanistic understanding of these regulatory signaling networks and how these networks affect eukaryotic cell migration.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.15
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• pp.6749-6751
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• 2015

Background: Laryngeal cancer is an important malignancy in head and neck area and squamous cell carcinoma (SCC) is the most common type accounting for 95% of cases. Increase in matrix metalloproteinases (MMPs) in different tumors and their correlation with tumor invasiveness has been documented. However, most studies have evaluated MMP-2 and MMP-9 expression and few have evaluated serum levels. The aim of current study was to evaluate serum levels in patients with laryngeal SCC compared to normal subjects and assess any relation with tumor clinicopathological findings. Materials and Methods: In this case control study, 20 patients with oral SCC and 20 healthy subjects were included. Serum levels of MMP-2 and MMP-9 were compared between groups and correlations with findings including grade (T) and node involvement (N) were evaluated. Results: Patients with laryngeal SCC had significantly higher serum levels of MMP-2 (p=0.01) and MMP-9 (p=0.03) compared to healthy subjects. Patients with higher T stage (T3,4) had significantly higher MMP-2 (p=0.04) and MMP-9 (p=0.01). There was significant positive correlation between serum levels of MMP-2 with T stage (r=0.45, p=0.04) and lymph node involvement (r=0.563, p=0.01) and between levels of MMP-9 with T stage (r=0.527, p=0.01). Conclusions: Our results showed that compared to healthy subjects, both MMP-2 and MMP-9 are significantly increased in serum of laryngeal SCC cases. MMP-2 was correlated with lymph node involvement while MMP-9 has stronger correlation with T stage compared to MMP-2.

• Journal of Information Display
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• v.7 no.1
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• pp.35-40
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• 2006

Organic light-emitting diode (OLED) display panel using the charge-pump (CP) pixel addressing scheme was fabricated, and the results show that it is applicable for information display. A CP-OLED panel with 64 ${\times}$ 64 pixels consisting of thin-film capacitors and amorphous silicon Schottky diodes was fabricated using conventional thin-film processes. The pixel drive circuit passes electrical current into the OLED cell during most of the frame period as in the thin-film transistor (TFT)-based active-matrix (AM) OLED displays. In this study, the panel was operated at a voltage level of below 4 V, and this operation voltage can be reduced by eliminating the overlap capacitance between the column bus line and the common electrode.

• The Transactions of the Korea Information Processing Society
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• v.1 no.4
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• pp.469-478
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• 1994

In this paper, a high speed, high resolution information processing digital- analog converter was designed for high definition color graphic, digital image signal processing, HDTV. For high speed operation, matrix type current cell array, latch which is not use pipelined, and two dimensional structure decoder using transmission gate were designed. It is adopted to fast-conversion, low-power implementation and exhibited high performance at linearity and accuracy. To reduce silicon area and to maintain resolution, current cell array composed of weighted and non-weighted current cells. In this paper, deglitching current cell design for high accuracy, new switching algorithm assert to reduce switching error. It's This circuit dissipates 130W with a 5-V power supply, and operate above 100MHz with 10 bit resolution.

• Membrane and Water Treatment
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• v.11 no.2
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• pp.131-139
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• 2020

The current study focused on the preparation of low-cost PVC-based adsorbing membrane. Metakaolin, as available adsorbent, was embedded into the PVC matrix via solution blending method. The as-prepared PVC/metakaolin mixed matrix membranes were characterized using scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy, atomic force microscopy (AFM), pure water permeability and contact angle measurements. The results confirmed the improvement of PWP and hydrophilicity due to the presence of metakaolin in the PVC matrix. Additionally the structure of PVC membrane was changed due to the incorporation of metakaolin in the polymer matrix. The static adsorption capacity of all samples was determined through dye removal. The effect of metakaolin dosage (0-7%) and pH (4, 8, 12) on dye adsorption capacity was investigated. The results depicted that the highest adsorption capacity was achieved at pH of 4 for all samples. Additionally, adsorption data were fitted on Langmuir, Freundlich, and Temkin models to determine the appropriate governing isotherm model. Finally, the dynamic adsorption capacity of the optimum PVC/metakaolin membrane was studied using dead-end filtration cell. The dye removal efficiency was determined for pure PVC and PVC/metakaolin membrane. The results demonstrated that PVC/metakaolin mixed matrix membrane had a high adsorption capacity for dye removal from aqueous solution.

• BMB Reports
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• v.43 no.5
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• pp.305-310
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• 2010

Syndecans, cell surface heparansulfate proteoglycans, have been proposed to act as cell surface receptors and/or coreceptors to play critical roles in multiple cellular functions. However, recent reports suggest that the function of syndecans can be further extended through shedding, a cleavage of extracellular domain. Shedding constitutes an additional level for controlling the function of syndecans, providing a means to attenuate and/or regulate amplitude and duration of syndecan signals by modulating the activity of syndecans as cell surface receptors. Whether these remaining cleavage products are still capable of functioning as cell surface receptors to efficiently transduce signals inside of cells is not clear. However, shedding transforms cell surface receptor syndecans into soluble forms, which, like growth factors, may act as novel ligands to induce cellular responses by association with other cell surface receptors. It is becoming interestingly evident that shed syndecans also contribute significantly to syndecan functions in cancer biology. This review presents current knowledge about syndecan shedding and its functional significance, particularly in the context of cancer.

• Proceedings of the IEEK Conference
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• 1999.11a
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• pp.689-692
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• 1999

This paper describes a 10-bit 75-MHz CMOS current-mode DAC designed for 0.8${\mu}{\textrm}{m}$ double-poly double-metal CMOS technology. This D/A converter is implemented using a current cell matrix that can drive a resistive load without output buffer. In the DAC. a current source is proposed to reduce the linearity error caused by the threshold-voltage variations over a wafer and the glitch energy caused by the time lagging, The integral and differential linearity error are founded to be within $\pm$0.35 LSB and $\pm$0.31 LSB respectively. The maximum conversion rate is about 80 MS/s. The total power dissipation is 160 ㎽ at 75 MS/s conversion rate.

• Nutritional Sciences
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• v.8 no.4
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• pp.242-249
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• 2005

It is well established that zinc plays an important role in bone metabolism and mineralization. The role of zinc in bone formation is well documented in animal models, but not much reported in cell models. In the present study, we evaluated zinc deficiency effects on osteoblastic cell proliferation, alkaline phosphatase activity and expression, and extracellular matrix bone nodule formation and bone-related gene expression in osteoblastic MC3T3-E1 cells. To deplete cellular zinc, chelexed-FBS and interpermeable zinc chelator TPEN were used. MC3T3-E1 cells were cultured in zinc concentration-dependent (0-15 ${\mu}M\;ZnCl_2$) and time-dependent (0-20 days) manners. MC3T3-E1 cell proliferation by MTT assay was increased as medium zinc level increased (p<0.05). Cellular Ca level and alkaline phosphatase activity were increased as medium zinc level increased (p<0.05). Alkaline phosphatase expression, a marker of commitment to the osteoblast lineage, measured by alkaline phosphatase staining was increased as medium zinc level increased. Extracellular calcium deposits measured by von Kossa staining for nodule formation also appeared higher in Zn+(15 ${\mu}M\;ZnCl_2$) than in Zn-(0 ${\mu}M\;ZnCl_2$). Bone formation marker genes, alkaline phosphatase and osteocalcin, were also expressed higher in Zn+ than in Zn-. The current work supports the beneficial effect of zinc on bone mineralization and bone-related gene expression. The results also promote further study as to the molecular mechanism of zinc deficiency for bone formation and thus facilitate to design preventive strategies for zinc-deficient bone diseases.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.6
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• pp.2187-2191
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• 2015

Background: Protrusive structures formed by migrating and invading cells are termed lamellipodia, filopodia, invadopodia and podosomes. Lamellipodia and filopodia appear on the leading edges of migrating cells and function to command the direction of the migrating cells. Invadopodia and podosomes are special F-actin-rich matrix-degrading structures that arise on the ventral surface of the cell membrane. Invadopodia are found in a variety of carcinomatous cells including squamous cell carcinoma of head and neck region whereas podosomes are found in normal highly motile cells of mesenchymal and myelomonocytic lineage. Invadopodia-associated protein markers consisted of 129 proteins belonging to different functional classes including WASP, NWASP, cortactin, Src kinase, Arp 2/3 complex, MT1-MMP and F-actin. To date, our current understanding on the role(s) of these regulators of actin dynamics in tumors of the orofacial region indicates that upregulation of these proteins promotes invasion and metastasis in oral squamous cell carcinoma, is associated with poor/worst prognostic outcome in laryngeal cancers, contributes to the persistent growth and metastasis characteristics of salivary gland adenoid cystic carcinoma, is a significant predictor of increased cancer risk in oral mucosal premalignant lesions and enhances local invasiveness in jawbone ameloblastomas.

• The Korean Journal of Urological Oncology
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• 제15권3호
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• pp.103-110
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• 2017

Cancer is the tissue complex consisted with heterogeneous cellular compositions, and microenvironmental cues. During the various stages of cancer initiation, development, and metastasis, cell-cell interactions as well as cell-extracellular matrix play major roles. Conventional cancer models both 2-dimensional and 3-dimensional (3D) present numerous limitations, which restrict their use as biomimetic models for drug screening and fundamental cancer biology studies. Recently, bioprinting biofabrication platform enables the creation of high-resolution 3D structures. Moreover this platform has been extensively used to model multiple organs and diseases, and this versatile technique has further found its creation of accurate models that figure out the complexity of the cancer microenvironment. In this review we will focus on cancer biology and limitations with current cancer models and we discuss vascular structures bioprinting that are critical to the construction of complex 3D cancer organoids. We finally conclude with current literature on bioprinting cancer models and propose future perspectives.