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Full-Text Articles in Engineering

Nanoroughened Surfaces For Efficient Capture Of Circulating Tumor Cells Without Using Capture Antibodies, Weiqiang Chen, Shinuo Weng, Feng Zhang, Steven Allen, Xiang Li, Liwei Bao, Raymond H. W. Lam, Jill A. Macoska, Sofia D. Merajver, Jianping Fu Nov 2012

Nanoroughened Surfaces For Efficient Capture Of Circulating Tumor Cells Without Using Capture Antibodies, Weiqiang Chen, Shinuo Weng, Feng Zhang, Steven Allen, Xiang Li, Liwei Bao, Raymond H. W. Lam, Jill A. Macoska, Sofia D. Merajver, Jianping Fu

Weiqiang Chen

Circulating tumor cells (CTCs) detached from both primary and metastatic lesions represent a potential alternative to invasive biopsies as a source of tumor tissue for the detection, characterization and monitoring of cancers. Here we report a simple yet effective strategy for capturing CTCs without using capture antibodies. Our method uniquely utilized the differential adhesion preference of cancer cells to nanorough surfaces when compared to normal blood cells and thus did not depend on their physical size or surface protein expression, a significant advantage as compared to other existing CTC capture techniques.


Effect Of Paired Apertures In A Periodic Hole Array On Higher Order Plasmon Modes, Fang-Tzu Chuang Nov 2012

Effect Of Paired Apertures In A Periodic Hole Array On Higher Order Plasmon Modes, Fang-Tzu Chuang

Fang-Tzu Chuang

We demonstrate that the transmission of higherorder surface plasmon modes in the mid-infrared range can be enhanced through rectangular hole array on the basis of paired apertures. Experiments prove that enhanced high-order transmission can be generated by either identical shapes or combinations of different hole shapes in pairs. The structure factor is adopted to explain the observed intensity of enhanced transmission. Numerical simulations of the enhanced secondorder mode verify a significant field enhancement in a unit cell of pairs. It is clarified that the separation between the paired apertures and the paired resonance is the key to determine certain higher-order …


Two Infrared Emission Modes With Different Wavelengths And Orthogonal Polarization In A Waveguide Thermal Emitter, Fang-Tzu Chuang Oct 2012

Two Infrared Emission Modes With Different Wavelengths And Orthogonal Polarization In A Waveguide Thermal Emitter, Fang-Tzu Chuang

Fang-Tzu Chuang

This study investigates a Au/SiO2/Au waveguide thermal emitter incorporating a metallic grating embedded in the SiO2 layer. The metal grating acts as a beam splitter, dividing the device into two waveguide structures determined by the polarization of the waveguide modes. The thermal radiation spectrum exhibits two peaks with orthogonal polarization. The emitted wavelengths of the two waveguide modes can be adjusted by controlling the thickness of the SiO2 layers on both sides of the metallic grating during the fabrication process. The emission peaks have ratios of the full width at half maximum to the peak wavelength of 0.057 and 0.05 …


Real-Time Analysis Of Brain Tumor Cell Dynamics: Novel Thermoelectric Detection Of L-Glutamate And Cell Metabolism Using Microfluidics, Siva Mahesh Tangutooru Oct 2012

Real-Time Analysis Of Brain Tumor Cell Dynamics: Novel Thermoelectric Detection Of L-Glutamate And Cell Metabolism Using Microfluidics, Siva Mahesh Tangutooru

Doctoral Dissertations

This study describes the design, fabrication and applications of a novel thermoelectric microfluidic bio-sensor. The bio-sensor is used for real time detection of the L-glutamate (L-glu) dynamics and metabolism for brain tumor cells immobilized in a microfluidic device. The microfluidic device is fabricated using a polymer/glass laminating technique (Xurography). An antimony-bismuth thin-film thermopile (primary sensing element) is integrated to the microfluidic device. The brain tumor cells are immobilized over the thermopile covering measuring and reference junctions of the thermopile using a poly-l-lysine coating layer. L-glutamate oxidase (L-GLOD) is immobilized over the measuring junctions of the thermopile prior to the immobilization …


Rapid Temporal Changes In The Expression Of A Set Of Neuromodulatory Genes During Alcohol Withdrawal In The Dorsal Vagal Complex: Molecular Evidence Of Homeostatic Disturbance., Kate Freeman, Mary M. Staehle, Zeynep H Gümüş, Rajanikanth Vadigepalli, Gregory E Gonye, Carmen N Nichols, Babatunde A Ogunnaike, Jan B Hoek, James S Schwaber Oct 2012

Rapid Temporal Changes In The Expression Of A Set Of Neuromodulatory Genes During Alcohol Withdrawal In The Dorsal Vagal Complex: Molecular Evidence Of Homeostatic Disturbance., Kate Freeman, Mary M. Staehle, Zeynep H Gümüş, Rajanikanth Vadigepalli, Gregory E Gonye, Carmen N Nichols, Babatunde A Ogunnaike, Jan B Hoek, James S Schwaber

Faculty Scholarship for the College of Science & Mathematics

BACKGROUND: Chronic alcohol exposure produces neuroadaptation, which increases the risk of cellular excitotoxicity and autonomic dysfunction during withdrawal. The temporal progression and regulation of the gene expression that contributes to this physiologic and behavioral phenotype is poorly understood early in the withdrawal period. Further, it is unexplored in the dorsal vagal complex (DVC), a brainstem autonomic regulatory structure.

METHODS: We use a quantitative polymerase chain reaction platform to precisely and simultaneously measure the expression of 145 neuromodulatory genes in more than 100 rat DVC samples from control, chronically alcohol-exposed, and withdrawn rats. To gain insight into the dynamic progression and …


Peptoid Based Slide Coatings For Disease Detection Via Elisa Microarray Analysis, Melissa Lea Hebert Aug 2012

Peptoid Based Slide Coatings For Disease Detection Via Elisa Microarray Analysis, Melissa Lea Hebert

Graduate Theses and Dissertations

Poly-N-substituted glycines (peptoids) are a very versatile family of synthetic molecules that can be customized for any number of applications. In this study, we chose to use peptoids as a foundation for sandwich ELISA microarray analysis with a long term goal of creating an early detection device for complex diseases such as cancer. The peptoids were designed to self-assemble into microspheres to be used in coatings on the surface of the microarray substrates to increase the surface area available for antibody attachment. This increased antibody density would lead to an increase in the microarray analysis sensitivity and dynamic range. Studies …


Nanoprojection Lithography Using Self-Assembled Interference Modules For Manufacturing Plasmonic Gratings, Fang-Tzu Chuang Jun 2012

Nanoprojection Lithography Using Self-Assembled Interference Modules For Manufacturing Plasmonic Gratings, Fang-Tzu Chuang

Fang-Tzu Chuang

Abstract—A new nanoprojection lithography (NPL) is proposed to manufacture plasmonic nanogratings. Here, low-cost self-assembly elastomeric polydimethylsiloxane wavy structures are used as the interference modules, with their periods and amplitudes largely controlled by the applied mechanical strain in the synthesis process. Well defined plasmonic grating couplers with desired feature sizes and wavelengths of operation were obtained. This NPL may enable large-area and flash manufacturing of plasmonic nanogratings with tunable array periods.


Electrospun Polycaprolactone Nanofiber Scaffolds For Tissue Engineering, Andreas Haukas May 2012

Electrospun Polycaprolactone Nanofiber Scaffolds For Tissue Engineering, Andreas Haukas

Graduate Theses and Dissertations

Stem cell and tissue engineering offer us with a unique opportunity to research and develop new therapies for treating various diseases that are otherwise incurable using traditional medicines. However, development of these new therapies replies upon the establishment of in vitro cell culture and differentiation systems that mimic in vivo microenvironments required for cell-cell and cell-ECM interaction. The development of these cell culture systems depends upon the identification of appropriate biomaterials and cell sources. Biomaterials should be carefully selected and fabricated into scaffolds for supporting cell growth and differentiation. In this study, we explored the fabrication of 3D electrospun nanofiber …


Nanotopography Influences Adhesion, Spreading, And Self-Renewal Of Human Embryonic Stem Cells, Weiqiang Chen, Luis G. Villa-Diaz, Yubing Sun, Shinuo Weng, Jin Koo Kim, Raymond H. W. Lam, Lin Han, Rong Fan, Paul H. Krebsbach, Jianping Fu Apr 2012

Nanotopography Influences Adhesion, Spreading, And Self-Renewal Of Human Embryonic Stem Cells, Weiqiang Chen, Luis G. Villa-Diaz, Yubing Sun, Shinuo Weng, Jin Koo Kim, Raymond H. W. Lam, Lin Han, Rong Fan, Paul H. Krebsbach, Jianping Fu

Weiqiang Chen

Human embryonic stem cells (hESCs) have great potentials for future cell-based therapeutics. However, their mechanosensitivity to biophysical signals from the cellular microenvironment is not well characterized. Here we introduced an effective microfabrication strategy for accurate control and patterning of nanoroughness on glass surfaces. Our results demonstrated that nanotopography could provide a potent regulatory signal over different hESC behaviors, including cell morphology, adhesion, proliferation, clonal expansion, and self-renewal. Our results indicated that topological sensing of hESCs might include feedback regulation involving mechanosensory integrin-mediated cell matrix adhesion, myosin II, and E-cadherin. Our results also demonstrated that cellular responses to nanotopography were cell-type …


Nonosecond Pulsed Electric Field Induced Changes In Dielectric Properties Of Biological Cells, Jie Zhuang Apr 2012

Nonosecond Pulsed Electric Field Induced Changes In Dielectric Properties Of Biological Cells, Jie Zhuang

Electrical & Computer Engineering Theses & Dissertations

Nanosecond pulsed electric field induced biological effects have been a focus of research interests since the new millennium. Promising biomedical applications, e.g. tumor treatment and wound healing, are emerging based on this principle. Although the exact mechanisms behind the nanosecond pulse-cell interactions are not completely understood yet, it is generally believed that charging along the cell membranes (including intracellular membranes) and formation of membrane pores trigger subsequent biological responses, and the number and quality of pores are responsible for the cell fate. The immediate charging response of a biological cell to a nanosecond pulsed electric field exposure relies on the …


Forisome Performance In Artificial Sieve Tubes, Michael Knoblauch, Mike Stubenrauch, Aart J.E. Van Bel, Winfried S. Peters Mar 2012

Forisome Performance In Artificial Sieve Tubes, Michael Knoblauch, Mike Stubenrauch, Aart J.E. Van Bel, Winfried S. Peters

Winfried S. Peters

In the legume phloem, sieve element occlusion (SEO) proteins assemble into Ca2+-dependent contractile bodies. These forisomes presumably control phloem transport by forming reversible sieve tube plugs. This function, however, has never been directly demonstrated, and appears questionable as forisomes were reported to be too small to plug sieve tubes, and failed to block flow efficiently in artificial microchannels. Moreover, plugs of SEO-related proteins in Arabidopsis sieve tubes do not affect phloem translocation. We improved existing procedures for forisome isolation and storage, and found that the degree of Ca2+-driven deformation that is possible in forisomes of Vicia faba, the standard …


Conclusion Panel, Allison Marsh Jan 2012

Conclusion Panel, Allison Marsh

Section 6: Conclusion

No abstract provided.


Why Do We Collect?, Allison Marsh Jan 2012

Why Do We Collect?, Allison Marsh

Section 2: Imaging the Microscopic

No abstract provided.


Imaging And Aesthetics, Allison Marsh Jan 2012

Imaging And Aesthetics, Allison Marsh

Section 2: Imaging the Microscopic

No abstract provided.


Capturing Motion, Allison Marsh Jan 2012

Capturing Motion, Allison Marsh

Section 3: Imaging the Fast Moving

No abstract provided.


Understanding Fracture, Allison Marsh Jan 2012

Understanding Fracture, Allison Marsh

Section 3: Imaging the Fast Moving

No abstract provided.


Listen, Allison Marsh Jan 2012

Listen, Allison Marsh

Section 3: Imaging the Fast Moving

No abstract provided.


Photographic Evidence, Allison Marsh Jan 2012

Photographic Evidence, Allison Marsh

Section 3: Imaging the Fast Moving

No abstract provided.


Spotlight On Usc: Mechanical Engineering, Allison Marsh Jan 2012

Spotlight On Usc: Mechanical Engineering, Allison Marsh

Section 3: Imaging the Fast Moving

No abstract provided.


Influencing Art, Allison Marsh Jan 2012

Influencing Art, Allison Marsh

Section 3: Imaging the Fast Moving

No abstract provided.


Spotlight On Usc: A.C. Moore Herbarium, Allison Marsh Jan 2012

Spotlight On Usc: A.C. Moore Herbarium, Allison Marsh

Section 2: Imaging the Microscopic

No abstract provided.


Enhanced Killing Effect Of Nanosecond Pulse Electric Fields On Panc1 And Jurkat Cell Lines In The Presence Of Tween 80, Gaurav Basu, Bhargava Subhash Kalluri, Ahmet Can Sabuncu, Christopher J. Osgood, Michael W. Stacey Jan 2012

Enhanced Killing Effect Of Nanosecond Pulse Electric Fields On Panc1 And Jurkat Cell Lines In The Presence Of Tween 80, Gaurav Basu, Bhargava Subhash Kalluri, Ahmet Can Sabuncu, Christopher J. Osgood, Michael W. Stacey

Bioelectrics Publications

We investigated the effects of nanosecond pulse electric fields (nsPEFs) on Jurkat and PANC1 cells, which are human carcinoma cell lines, in the presence of Tween 80 (T80) at a concentration of 0.18% and demonstarted an enhanced killing effect. We used two biological assays to determine cell viability after exposing cells to nsPEFs in the presence of T80 and observed a significant increase in the killing effect of nsPEFs. We did not see a toxic effect of T80 when cells were exposed to surfactant alone. However, we saw a synergistic effect when cells exposed to T80 were combined with the …


Decorin Expression, Straw-Like Structure, And Differentiation Of Human Costal Cartilage, Michael W. Stacey, Janna Grubb, Anthony Asmar, Julie Pryor, Hani Elsayed-Ali, Ali Beskok, Diganta Dutta, Annie Fecteau, Alice Werner, Dennis A. Darby, Robert Kelly Jan 2012

Decorin Expression, Straw-Like Structure, And Differentiation Of Human Costal Cartilage, Michael W. Stacey, Janna Grubb, Anthony Asmar, Julie Pryor, Hani Elsayed-Ali, Ali Beskok, Diganta Dutta, Annie Fecteau, Alice Werner, Dennis A. Darby, Robert Kelly

Bioelectrics Publications

Costal cartilage is much understudied compared with the load-bearing cartilages. Abnormally grown costal cartilages are associated with the inherited chest wall deformities pectus excavatum and pectus carinatum resulting in sunken and pigeon chests, respectively. A lack of understanding of the ultrastructural and molecular biology of costal cartilage is a major confounder in predicting causes and outcomes of these disorders. This study analyzed the structure of marginal human costal cartilage (ribs 6-10) through scanning electron and atomic force microscopes and identified the presence of straw-like structures running longitudinally. We also demonstrated that chondrocytes tend to occur singly or as doublets and …


Oxidative Effects Of Nanosecond Pulsed Electric Field Exposure In Cells And Cell-Free Media, Olga N. Pakhomova, Vera A. Khorokhorina, Angela M. Bowman, Raminta Rodaitė-Riševičienė, Gintautas Saulis, Shu Xiao, Andrei G. Pakhomov Jan 2012

Oxidative Effects Of Nanosecond Pulsed Electric Field Exposure In Cells And Cell-Free Media, Olga N. Pakhomova, Vera A. Khorokhorina, Angela M. Bowman, Raminta Rodaitė-Riševičienė, Gintautas Saulis, Shu Xiao, Andrei G. Pakhomov

Bioelectrics Publications

Nanosecond pulsed electric field (nsPEF) is a novel modality for permeabilization of membranous structures and intracellular delivery of xenobiotics. We hypothesized that oxidative effects of nsPEF could be a separate primary mechanism responsible for bioeffects. ROS production in cultured cells and media exposed to 300-ns PEF (1–13 kV/cm) was assessed by oxidation of 2′, 7′-dichlorodihydrofluoresein (H2DCF), dihidroethidium (DHE), or Amplex Red. When a suspension of H2DCF-loaded cells was subjected to nsPEF, the yield of fluorescent 2′,7′dichlorofluorescein (DCF) increased proportionally to the pulse number and cell density. DCF emission increased with time after exposure in nsPEF-sensitive Jurkat …


A Preliminary Study On The Potential Of Manuka Honey And Platelet-Rich Plasma In Wound Healing, Scott A. Sell, Patricia S. Wolfe, Andrew J. Spence, Isaac A. Rodriguez, Jennifer M. Mccoll, Rebecca L. Petrella, Koyal Garg, Jeffery J. Ericksen, Gary L. Bowlin Jan 2012

A Preliminary Study On The Potential Of Manuka Honey And Platelet-Rich Plasma In Wound Healing, Scott A. Sell, Patricia S. Wolfe, Andrew J. Spence, Isaac A. Rodriguez, Jennifer M. Mccoll, Rebecca L. Petrella, Koyal Garg, Jeffery J. Ericksen, Gary L. Bowlin

Nursing Faculty Publications

Aim. The purpose of this study was to determine the in vitro response of cells critical to the wound healing process in culture media supplemented with a lyophilized preparation rich in growth factors (PRGF) and Manuka honey. Materials and Methods. This study utilized cell culture media supplemented with PRGF, as well as whole Manuka honey and the medical-grade Medihoney (MH), a Manuka honey product. The response of human fibroblasts (hDF), macrophages, and endothelial cells (hPMEC) was evaluated, with respect to cell proliferation, chemotaxis, collagen matrix production, and angiogenic potential, when subjected to culture with media containing PRGF, MH, Manuka honey, …


Probing Nanoparticle Interactions In Cell Culture Media, Ahmet C. Sabuncu, Janna Grubbs, Shizhi Qian, Tarek M. Abdel-Fattah, Michael W. Stacey, Ali Beskok Jan 2012

Probing Nanoparticle Interactions In Cell Culture Media, Ahmet C. Sabuncu, Janna Grubbs, Shizhi Qian, Tarek M. Abdel-Fattah, Michael W. Stacey, Ali Beskok

Bioelectrics Publications

Nanoparticle research is often performed in vitro with little emphasis on the potential role of cell culture medium. In this study, gold nanoparticle interactions with cell culture medium and two cancer cell lines (human T-cell leukemia Jurkat and human pancreatic carcinoma PANC1) were investigated. Gold nanoparticles of 10, 25, 50, and 100 nm in diameter at fixed mass concentration were tested. Size distributions and zeta potentials of gold nanoparticles suspended in deionized (DI) water and Dulbecco's Modified Eagle's Media (DMEM) supplemented with fetal calf serum (FCS) were measured using dynamic light scattering (DLS) technique. In DI water, particle size distributions …