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Results 201 - 250 of 1679
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Tarantola Marco - - 2010
Early determination of the metastatic potential of cancer cells is a crucial step for successful oncological treatment. Besides the remarkable progress in molecular genomics- or proteomics-based diagnostics, there is a great demand for in vitro biosensor devices that allow rapid and selective detection of the invasive properties of tumor cells. ...
Butterworth Karl T - - 2010
The delivery of spatially modulated radiation fields has been shown to impact on in vitro cell survival responses. To study the effect of modulated fields on cell survival, dose response curves were determined for human DU-145 prostate, T98G glioma tumour cells and normal primary AGO-1552 fibroblast cells exposed to modulated ...
Ramasamy Easwaramoorthi - - 2010
A counter-electrode comprised of large-pore sized mesoporous carbon exhibits low charge transfer resistance in iodide/triiodide redox electrolyte, thus liquid and quasi-solid dye sensitized solar cells show 8.18% and 3.61% solar to electric energy conversion efficiency, respectively.
Hernández Rosa M A - - 2010
In recent years, the use of transplanted living cells pumping out active factors directly at the site has proven to be an emergent technology. However a recurring impediment to rapid development in the field is the immune rejection of transplanted allo- or xenogeneic cells. Immunosuppression is used clinically to prevent ...
Lombardini Marta - - 2010
We present the structure of an open microwell, i.e. a microwell open at both the top and bottom ends, which enables single-cells to be handled, processed and recovered after the experiment. The microwell has a novel architecture which allows particles to be trapped and forced to interact by means of ...
Zakin Lise - - 2010
In the developing organism, cells differentiate, divide and die as part of groups of hundreds or thousands of cells called 'morphogenetic fields'. Fields have the remarkable property of self-regulation: for example, if the forelimb field is bisected, each half can give rise to a complete limb after transplantation, as discovered ...
Zeitoun Ramsey I - - 2010
Procedures requiring precise and accurate positioning of particles and cells have impacted a broad range of research interests including molecular detection, self-assembly and tissue and cell engineering. These fields would be greatly aided by more advanced, yet straightforward, micro-object positioning methods that are precise, scalable, responsive and flexible. We have ...
Henighan T - - 2010
A platform of discrete microscopic magnetic elements patterned on a surface offers dynamic control over the motion of fluid-borne cells by reprogramming the magnetization within the magnetic bits. T-lymphocyte cells tethered to magnetic microspheres and untethered leukemia cells are remotely manipulated and guided along desired trajectories on a silicon surface ...
Hirose Hideki - - 2010
Given the widespread use of the cellular phone today, investigation of potential biological effects of radiofrequency (RF) fields has become increasingly important. In particular, much research has been conducted on RF effects on brain function. To examine any biological effects on the central nervous system (CNS) induced by 1950 MHz ...
Bombelli Cecilia - - 2010
Liposomes formulated with dimyristoyl-sn-glycero-phosphatidylcholine, DMPC, and either one of the cationic gemini surfactants (S,S)-2,3-dimethoxy-1,4-bis(N-hexadecyl-N,N-dimethylammonio)butane bromide, 1a, and (S,R)-2,3-dimethoxy-1,4-bis(N-hexadecyl-N,N-dimethylammonio)butane bromide, 1b, were investigated as vehicles of the photosensitizer m-tetrahydroxyphenylchlorin, m-THPC, to cell models of malignant glioma. The delivery efficiency of DMPC/1a and DMPC/1b liposome formulations were evaluated on the murine glioblastoma ...
Zhu Tao - - 2010
Microfluidics-based cell electroporation has many advantages in delivering small molecules into cells. In this study, hydrodynamic focusing of fluids with different conductivities has been used for high through-put cell electroporation at low voltage (<3 V) of continuous direct current (dc) power. Simulation results showed that an input voltage of only ...
Toivola Minna - - 2010
Stainless steel based dye solar cells have been upscaled from small, laboratory size test cells of 0.32 cm2 active area to 6 cm x 6 cm "mini-modules" with active areas ca. 15 cm2. Stainless steel works as the photoelectrode substrate whilst the counter electrode is prepared on indium-doped tin oxide ...
Loomis Kristin - - 2010
The CD22 antigen is a viable target for therapeutic intervention for B-cell lymphomas. Several therapeutic anti-CD22 antibodies as well as an anti-CD22-based immunotoxin (HA22) are currently under investigation in clinical settings. Coupling of anti-CD22 reagents with a nano-drug delivery vehicle is projected to significantly improve treatment efficacies. Therefore, we generated ...
Thein Myo - - 2010
The underlying sensing mechanism of single-cell-based integrated microelectrode array (IMA) biosensors was investigated via experimental and modeling studies. IMA chips were microfabricated and single-cell-level manipulation was achieved through surface chemistry modification of IMA chips. Individual fibroblast cells (NIH3T3) were immobilized on either lysine-arginine-glycine-aspartic acid (KRGD) short peptide-modified or fibronectin extracellular-cell-adhesion-molecule-modified ...
Shafiee Hadi - - 2010
Contactless dielectrophoresis (cDEP) is a recently developed method of cell manipulation in which the electrodes are physically isolated from the sample. Here we present two microfluidic devices capable of selectively isolating live human leukemia cells from dead cells utilizing their electrical signatures. The effect of different voltages and frequencies on ...
Kobel Stefan - - 2010
The poor efficiency of microfluidic single cell trapping is currently restricting the full potential of state-of-the-art single cell analyses. Using fluid dynamics simulations in combination with particle image velocimetry to systematically optimize trap architectures, we present a microfluidic chip with enhanced single cell trapping and on-chip culture performance. Upon optimization ...
Ciesielski Peter N - - 2010
Photosynthesis is the process by which Nature coordinates a tandem of protein complexes of impressive complexity that function to harness staggering amounts of solar energy on a global scale. Advances in biochemistry and nanotechnology have provided tools to isolate and manipulate the individual components of this process, thus opening a ...
Burks Scott R SR Medical Biotechnology Center, University of Maryland Biotechnology Institute, 725 W Lombard St, Baltimore, MD 21201, - - 2010
Electron paramagnetic resonance (EPR) imaging is an emerging modality that can detect and localize paramagnetic molecular probes (so-called spin probes) in vivo. We previously demonstrated that nitroxide spin probes can be encapsulated in liposomes at concentrations exceeding 100 mM, at which nitroxides exhibit a concentration-dependent quenching of their EPR signal ...
Gagnon Zachary - - 2010
We integrate electrothermally induced micro-pumps and dielectrophoretic (DEP) traps into micro-circulating fluidic channel loops for yeast cell concentration and separation, two important on-chip cell manipulation tasks, with the same embedded electrodes on-chip. Each fluidic loop design contains well-defined high and low field regions that serve for both fluid transport and ...
Fondell Amelie - - 2010
PURPOSE: For the treatment of cancer, the therapeutic potential of short-range, low-energy Auger-electron emitters, such as (125)I, is getting progressively wider recognition. The potency of Auger-electron emitters is strongly dependent on their location in close vicinity to DNA. We have developed a new two-step targeting strategy to transport (125)I into ...
Kamps Jan A - - 2010
Liposome-cell interactions have been assessed for over 30 years now by an enormous variety of approaches and methods. In-depth knowledge of liposome-cell interaction is still very relevant since new concepts and applications applying liposomes are being developed every day. This chapter does not aim to give a complete overview on ...
Church Christopher - - 2010
Lysing cells is an important step in the analysis of intracellular contents. Concentrating cells is often required in order to acquire adequate cells for lysis. This work presents an integrated concentration and lysis of mammalian cells in a constriction microchannel using dc-biased ac electric fields. By adjusting the dc component, ...
Zhu Ke - - 2010
The dielectrophoretic behavior of active, dead, and dormant Mycobacterium smegmatis bacterial cells was studied. It was found that the 72-h-old dormant cells had a much higher effective particle conductivity (812+/-10 muS cm(-1)), almost double that of active cells (560+/-20 muS cm(-1)), while that of dead (autoclaved) M. smegmatis cells was ...
Sekijima Masaru - - 2010
We investigated the mechanisms by which radiofrequency (RF) fields exert their activity, and the changes in both cell proliferation and the gene expression profile in the human cell lines, A172 (glioblastoma), H4 (neuroglioma), and IMR-90 (fibroblasts from normal fetal lung) following exposure to 2.1425 GHz continuous wave (CW) and Wideband ...
Hoettges Kai F - - 2010
Dielectrophoresis (DEP) is a technique which offers label-free measurement of cell electrophysiology by monitoring its movement in non-uniform electric fields. In this chapter, the theory underlying DEP is explored, as are the implications of the development of equipment for taking such measurements. Practical considerations such as the selection of a ...
Jun Bong-Hyun - - 2010
In this study, surface-enhanced Raman spectroscopy (SERS)-encoded magnetic nanoparticles (NPs) are prepared and utilized as a multifunctional tagging material for cancer-cell targeting and separation. First, silver-embedded magnetic NPs are prepared, composed of an 18-nm magnetic core and a 16-nm-thick silica shell with silver NPs formed on the surface. After simple ...
Mendon?a Liliana S - - 2010
The present work aimed at the development and application of transferrin receptor (TrfR)-targeted sterically stabilized liposomes encapsulating anti-BCR-ABL siRNA or asODN. Transferrin was coupled to the surface of liposomes encapsulating siRNA or asODN through the postinsertion method. Cell association and internalization were assessed by flow cytometry and confocal microscopy, respectively. ...
Fei Zhengzheng - - 2010
Electroporation is one of the most popular nonviral gene transfer methods for embryonic stem cell transfection. Bulk electroporation techniques, however, require a high electrical field and provide a nonuniform electrical field distribution among randomly distributed cells, leading to limited transfection efficiency and cell viability, especially for a low number of ...
Santos Edorta - - 2010
The field of cell encapsulation is advancing rapidly. This cell-based technology permits the local and long-term delivery ofa desired therapeutic product reducing or even avoiding the need ofimmunosuppressant drugs. The choice of a suitable material preserving the viability and functionality of enclosed cells becomes fundamental if a therapeutic aim is ...
Mykhaylyk Olga - - 2010
In a magnetofection procedure, self-assembling complexes of enhancers like cationic lipids with plasmid DNA or small interfering RNA (siRNA) are associated with magnetic nanoparticles and are then concentrated at the surface of cultured cells by applying a permanent inhomogeneous magnetic field. This process results in a considerable improvement in transfection ...
Wiegering V - - 2010
Juvenile Idiopathic Arthritis (JIA) is the most common cause of chronic arthritis in childhood and adolescents and encompasses a heterogeneous group of different diseases. Due to the promising results of B-cell depleting therapies in rheumatoid arthritis the role of B-cells in autoimmune diseases has to be discussed in a new ...
Thomas Rupert S W - - 2010
We describe a system for the isolation, concentration, separation, and recovery of human osteoblast-like cells from a heterogeneous population using dielectrophoretic ring traps. Cells flowing in a microfluidic channel are immobilized inside an electric field cage using negative dielectrophoresis. A planar ring electrode creates a closed trap while repelling surrounding ...
Orive Gorka - - 2010
The exciting developments in the field of drug delivery have already had an enormous impact on medical technology, facilitating the administration of many drugs and improving the pharmacokinetics of many others. The past few years have also seen several firsts, including the design of novel tissue engineered approaches, intriguing advances ...
Sawan M M Polystim Neurotechnologies Laboratory, Dept. of Elec. Eng., Polytechnique Montréal, - - 2010
We describe in this paper cells sensing and manipulation methods, as well as platforms based on Lab-on-chip devices. Among other contributions, new circuit and microfluidic techniques, and packaging methods are proposed for efficient cells manipulation and detection. The proposed devices include high-sensitivity sensing circuits (200 mV/fF), low-pressure liquid injection interfaces ...
Fatoyinbo Henry O HO Centre for Biomedical Engineering, Faculty of Engineering and Physical Sciences, University of Surrey, Duke of Kent Building (L5), Guildford, GU2 7XH, United Kingdom. - - 2010
In this paper, the use of non-uniform ac electric fields on biological cells for bioanalysis, through multiple, independently configurable channels is presented. The programmable system has been used to obtain the dielectrophoretic spectra of cells in near real time, within 90 seconds. This is a significant improvement on existing dielectrophoretic ...
Braeken Dries D Bioelectronics Group, Imec, Kapeldreef 75, 3001 Leuven, Belgium. - - 2010
In drug screening and pharmaceutical research, high-throughput systems that are able to perform single-cell measurements are highly desired. Micro-electrode arrays try to answer this need but still suffer from significant drawbacks such as a small amount of electrodes and the inability to address single cells. Here, we present a novel ...
Minnikanti S S Electrical and Computer Engineering Dept. of George Mason University, Fairfax VA, USA. - - 2010
While there have been many attempts at patterning cells onto substrates, a reliable method for trapping cell clusters and forming cell arrays in a predefined geometry remains to be demonstrated. We intend to develop a multielectrode array platform to initially trap cells via dielectrophoresis (DEP) and to later measure their ...
Saczko Jolanta - - 2010
The effectiveness of the photodynamic therapy (PDT), a low-invasive and targeted therapy of cancer, could be intensified by increasing the intracellular transport of a photosensitizer. The electroporation is used to generate non-specific transient nanopores that facilitate local drug delivery into cells. Photodynamic therapy assisted by electroporation was tested in vitro ...
Lee Seung Won - - 2010
A single-compartmented microbial fuel cell composed of a graphite felt anode modified with Neutral Red (NR-anode) and a porous Fe(II)-carbon cathode (FeC-cathode) were compared for electricity generation from Microbacterium sp. and Pseudomonas sp. under identical conditions. Pseudomonas sp. was more than four times the size of Microbacterium sp. based on ...
Santos Adriana O - - 2010
Anticancer systemic gene silencing therapy has been so far limited by the inexistence of adequate carrier systems that ultimately provide an efficient intracellular delivery into target tumor cells. In this respect, one promising strategy involves the covalent attachment of internalizing-targeting ligands at the extremity of PEG chains grafted onto liposomes. ...
Pan Yuliang - - 2010
A novel method for selective collection and detection of human acute leukemia cells has been proposed using aptamer-conjugated magnetic beads (apt-MBs) and a magnet-quartz crystal microbalance (QCM) system. The sgc8c aptamer-conjugated MBs specifically binding to CCRF-CEM cells were used for target cell extraction from complex matrixes, and the magnet-QCM system ...
Dekker Arjan - - 2009
Scaling up microbial fuel cells (MFCs) is inevitable when power outputs have to be obtained that can power electrical devices other than small sensors. This research has used a bipolar plate MFC stack of four cells with a total working volume of 20 L and a total membrane surface area ...
Ul Haque Aeraj - - 2009
Advancements in microfabrication technology have lead to the development of planar micro-pore electroporation technology. This technology has been shown to provide greater control in single cell manipulation, and electroporation which is independent from cell size. In this work we report direct and spatially resolved characterization of electric currents within a ...
McCaig Colin D - - 2009
Cells undergo a variety of physiological processes, including division, migration and differentiation, under the influence of endogenous electrical cues, which are generated physiologically and pathologically in the extracellular and sometimes intracellular spaces. These signals are transduced to regulate cell behaviours profoundly, both in vitro and in vivo. Bioelectricity influences cellular ...
Mykhaylyk Olga - - 2009
The magnetic labeling of living cells has become of major interest in the areas of cell therapy and tissue engineering. Magnetically labeled cells have been reported to allow increased and controlled seeding, tracking, and targeting of cells. In this work, we comprehensively characterize magnetic nanoparticles (MNPs) possessing a magnetite core ...
Chen Chin-Yu - - 2009
For this study, twisted nematic liquid crystals (TN-LCs) are sandwiched between two cross-embedded wire-grid polarizers (WGPs) as alignment and electrodes for projection displays. In the proposed device, the WGPs replace not only the sheet polarizers in a conventional TN-LC cell, but also the front and rear alignment layers and transparent ...
Pérez-Castejón C - - 2009
Common concern about the biological effects of electromagnetic fields (EMF) is increasing with the expansion of X-band microwaves (MW). The purpose of our work was to determine whether exposure to MW pulses in this range can induce toxic effects on human astrocytoma cells. Cultured astrocytoma cells (Clonetics line 1321N1) were ...
Kim Dong-Hyun - - 2010
Nanomagnetic materials offer exciting avenues for probing cell mechanics and activating mechanosensitive ion channels, as well as for advancing cancer therapies. Most experimental works so far have used superparamagnetic materials. This report describes a first approach based on interfacing cells with lithographically defined microdiscs that possess a spin-vortex ground state. ...
Upadhyaya Sarvesh - - 2010
Cell based screening assays are increasingly used in drug discovery due to the physiological significance of the results and high content information obtained from them. Miniaturization of this format, currently carried out in microwell plates, is at its limit due to increased unnatural interaction of cells with walls inside micro-wells. ...
Robert Damien - - 2010
The in vitro generation of engineered tissue constructs involves the seeding of cells into porous scaffolds. Ongoing challenges are to design scaffolds to meet biochemical and mechanical requirements and to optimize cell seeding in the constructs. In this context, we have developed a simple method based on a magnetic tweezer ...
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