468 results on '"Gimzewski, James K"'
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2. Controlled Vertical Transfer of Individual Au Atoms Using a Surface Supported Carbon Radical for Atomically Precise Manufacturing
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Bothra, Pallavi, Stieg, Adam Z, Gimzewski, James K, and Sautet, Philippe
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- 2023
3. NANO: Bottom up and in Between
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Vesna, Victoria, primary and Gimzewski, James K., additional
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- 2023
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4. Nonequilibrium Casimir effects of nonreciprocal surface waves
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Khandekar, Chinmay, Buddhiraju, Siddharth, Wilkinson, Paul R., Gimzewski, James K., Rodriguez, Alejandro W., Chase, Charles, and Fan, Shanhui
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Quantum Physics ,Condensed Matter - Mesoscale and Nanoscale Physics ,Physics - Optics - Abstract
We show that an isotropic dipolar particle in the vicinity of a substrate made of nonreciprocal plasmonic materials can experience a lateral Casimir force and torque when the particle's temperature differs from that of the slab and the environment. We connect the existence of the lateral force to the asymmetric dispersion of nonreciprocal surface polaritons and the existence of the lateral torque to the spin-momentum locking of such surface waves. Using the formalism of fluctuational electrodynamics, we show that the features of lateral force and torque should be experimentally observable using a substrate of doped Indium Antimonide (InSb) placed in an external magnetic field, and for a variety of dielectric particles. Interestingly, we also find that the directions of the lateral force and the torque depend on the constituent materials of the particles, which suggests a sorting mechanism based on lateral nonequilibrium Casimir physics.
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- 2021
5. Pacemaker translocations and power laws in 2D stem cell-derived cardiomyocyte cultures
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Dunham, Christopher S, Mackenzie, Madelynn E, Nakano, Haruko, Kim, Alexis R, Juda, Michal B, Nakano, Atsushi, Stieg, Adam Z, and Gimzewski, James K
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Physical Sciences ,Condensed Matter Physics ,Cardiovascular ,Stem Cell Research ,Cell Culture Techniques ,Myocytes ,Cardiac ,Pacemaker ,Artificial ,Stem Cells ,General Science & Technology - Abstract
Power laws are of interest to several scientific disciplines because they can provide important information about the underlying dynamics (e.g. scale invariance and self-similarity) of a given system. Because power laws are of increasing interest to the cardiac sciences as potential indicators of cardiac dysfunction, it is essential that rigorous, standardized analytical methods are employed in the evaluation of power laws. This study compares the methods currently used in the fields of condensed matter physics, geoscience, neuroscience, and cardiology in order to provide a robust analytical framework for evaluating power laws in stem cell-derived cardiomyocyte cultures. One potential power law-obeying phenomenon observed in these cultures is pacemaker translocations, or the spatial and temporal instability of the pacemaker region, in a 2D cell culture. Power law analysis of translocation data was performed using increasingly rigorous methods in order to illustrate how differences in analytical robustness can result in misleading power law interpretations. Non-robust methods concluded that pacemaker translocations adhere to a power law while robust methods convincingly demonstrated that they obey a doubly truncated power law. The results of this study highlight the importance of employing comprehensive methods during power law analysis of cardiomyocyte cultures.
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- 2022
6. Cardio PyMEA: A user-friendly, open-source Python application for cardiomyocyte microelectrode array analysis
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Dunham, Christopher S, Mackenzie, Madelynn E, Nakano, Haruko, Kim, Alexis R, Nakano, Atsushi, Stieg, Adam Z, and Gimzewski, James K
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Information and Computing Sciences ,Applied Computing ,Cardiovascular ,Cardiac Electrophysiology ,Microelectrodes ,Myocytes ,Cardiac ,Software ,General Science & Technology - Abstract
Open source analytical software for the analysis of electrophysiological cardiomyocyte data offers a variety of new functionalities to complement closed-source, proprietary tools. Here, we present the Cardio PyMEA application, a free, modifiable, and open source program for the analysis of microelectrode array (MEA) data obtained from cardiomyocyte cultures. Major software capabilities include: beat detection; pacemaker origin estimation; beat amplitude and interval; local activation time, upstroke velocity, and conduction velocity; analysis of cardiomyocyte property-distance relationships; and robust power law analysis of pacemaker spatiotemporal instability. Cardio PyMEA was written entirely in Python 3 to provide an accessible, integrated workflow that possesses a user-friendly graphical user interface (GUI) written in PyQt5 to allow for performant, cross-platform utilization. This application makes use of object-oriented programming (OOP) principles to facilitate the relatively straightforward incorporation of custom functionalities, e.g. power law analysis, that suit the needs of the user. Cardio PyMEA is available as an open source application under the terms of the GNU General Public License (GPL). The source code for Cardio PyMEA can be downloaded from Github at the following repository: https://github.com/csdunhamUC/cardio_pymea.
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- 2022
7. Spoken Digit Classification by In-Materio Reservoir Computing with Neuromorphic Atomic Switch Networks
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Lilak, Sam, Woods, Walt, Scharnhorst, Kelsey, Dunham, Christopher, Teuscher, Christof, Stieg, Adam Z., and Gimzewski, James K.
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Computer Science - Emerging Technologies ,Condensed Matter - Disordered Systems and Neural Networks ,Condensed Matter - Mesoscale and Nanoscale Physics ,Condensed Matter - Materials Science - Abstract
Atomic Switch Networks (ASN) comprising silver iodide (AgI) junctions, a material previously unexplored as functional memristive elements within highly-interconnected nanowire networks, were employed as a neuromorphic substrate for physical Reservoir Computing (RC). This new class of ASN-based devices has been physically characterized and utilized to classify spoken digit audio data, demonstrating the utility of substrate-based device architectures where intrinsic material properties can be exploited to perform computation in-materio. This work demonstrates high accuracy in the classification of temporally analyzed Free-Spoken Digit Data (FSDD). These results expand upon the class of viable memristive materials available for the production of functional nanowire networks and bolster the utility of ASN-based devices as unique hardware platforms for neuromorphic computing applications involving memory, adaptation and learning., Comment: 11 pages, 7 figures
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- 2021
8. Monomolecular covalent honeycomb nanosheets produced by surface-mediated polycondensation between 1,3,5-triamino benzene and benzene-1,3,5-tricarbox aldehyde on Au(111)
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Kunitake, Masashi, Tanoue, Ryota, Higuchi, Rintaro, Yoshimoto, Soichiro, Haraguchi, Ryusei, Uemura, Shinobu, Kimizuka, Nobuo, Stieg, Adam Z, and Gimzewski, James K
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Fabrication of a two-dimensional covalent network of honeycomb nanosheets comprising small 1,3,5-triamino benzene and benzene-1,3,5-tricarboxaldehyde aromatic building blocks was conducted on Au(111) in a pH-controlled aqueous solution. In situ scanning tunneling microscopy revealed a large defect-free and homogeneous honeycomb π-conjugated nanosheet at the Au(111)/liquid interface. An electrochemical potential dependence indicated that the nanosheets were the result of thermodynamic self-assembly based not only on the reaction equilibrium but also on the adsorption (partition) equilibrium, which was controlled by the building block surface coverage as a function of electrode potential.
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- 2020
9. Single Cell Mechanotype and Associated Molecular Changes in Urothelial Cell Transformation and Progression
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Yu, Weibo, Lu, Qing-Yi, Sharma, Shivani, Ly, Chau, Di Carlo, Dino, Rowat, Amy C, LeClaire, Michael, Kim, Donghyuk, Chow, Christine, Gimzewski, James K, and Rao, Jianyu
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Biochemistry and Cell Biology ,Biomedical and Clinical Sciences ,Biological Sciences ,Bioengineering ,Women's Health ,Biotechnology ,Cancer ,Aetiology ,2.1 Biological and endogenous factors ,cell mechanotype ,bladder cancer ,cell stiffness ,cell deformability ,cancer progression ,EMT ,Biological sciences ,Biomedical and clinical sciences - Abstract
Cancer cell mechanotype changes are newly recognized cancer phenotypic events, whereas metastatic cancer cells show decreased cell stiffness and increased deformability relative to normal cells. To further examine how cell mechanotype changes in early stages of cancer transformation and progression, an in vitro multi-step human urothelial cell carcinogenic model was used to measure cellular Young's modulus, deformability, and transit time using single-cell atomic force microscopy, microfluidic-based deformability cytometry, and quantitative deformability cytometry, respectively. Measurable cell mechanotype changes of stiffness, deformability, and cell transit time occur early in the transformation process. As cells progress from normal, to preinvasive, to invasive cells, Young's modulus of stiffness decreases and deformability increases gradually. These changes were confirmed in three-dimensional cultured microtumor masses and urine exfoliated cells directly from patients. Using gene screening and proteomics approaches, we found that the main molecular pathway implicated in cell mechanotype changes appears to be epithelial to mesenchymal transition.
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- 2020
10. Emergent dynamics of neuromorphic nanowire networks.
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Diaz-Alvarez, Adrian, Higuchi, Rintaro, Sanz-Leon, Paula, Marcus, Ido, Shingaya, Yoshitaka, Stieg, Adam Z, Gimzewski, James K, Kuncic, Zdenka, and Nakayama, Tomonobu
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Neuromorphic networks are formed by random self-assembly of silver nanowires. Silver nanowires are coated with a polymer layer after synthesis in which junctions between two nanowires act as resistive switches, often compared with neurosynapses. We analyze the role of single junction switching in the dynamical properties of the neuromorphic network. Network transitions to a high-conductance state under the application of a voltage bias higher than a threshold value. The stability and permanence of this state is studied by shifting the voltage bias in order to activate or deactivate the network. A model of the electrical network with atomic switches reproduces the relation between individual nanowire junctions switching events with current pathway formation or destruction. This relation is further manifested in changes in 1/f power-law scaling of the spectral distribution of current. The current fluctuations involved in this scaling shift are considered to arise from an essential equilibrium between formation, stochastic-mediated breakdown of individual nanowire-nanowire junctions and the onset of different current pathways that optimize power dissipation. This emergent dynamics shown by polymer-coated Ag nanowire networks places this system in the class of optimal transport networks, from which new fundamental parallels with neural dynamics and natural computing problem-solving can be drawn.
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- 2019
11. Piezoelectric needle sensor reveals mechanical heterogeneity in human thyroid tissue lesions.
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Sharma, Shivani, Aguilera, Renato, Rao, JianYu, and Gimzewski, James K
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Palpable thyroid lesions are common, and although mostly benign, lethal malignant nodules do occur and may be difficult to differentiate. Here, we introduce the use of a piezoelectric system called Smart-touch fine needle (or STFN) mounted directly onto conventional biopsy needles, to evaluate abnormal tissues, through quantitative real-time measurements of variations in tissue stiffness as the needle penetrates tissue. Using well-characterized biomaterials of known stiffness and explanted animal tissue models, we first established experimental protocols for STFN measures on biological tissues, as well as optimized device design for high signal-to-noise ratio. Freshly excised patient thyroids with varying fibrotic and malignant potential revealed discrete variations in STFN based tissue stiffness/stiffness heterogeneity and correlated well with final histopathology. Our piezoelectric needle sensor reveals mechanical heterogeneity in thyroid tissue lesions and provides a foundation for the design of hand-held tools for the rapid, mechano-profiling of malignant lesions in vivo while performing fine needle aspiration (FNA).
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- 2019
12. Potential role of MRN-100, an iron-based compound, in upregulating production of cytokine IL-10 in human dendritic cells to promote an anti-inflammatory response in vitro
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Ghoneum, Mamdooh H, Gimzewski, James K, Ghoneum, Aya D, and Agrawal, Sudhanshu
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Biomedical and Clinical Sciences ,Immunology ,Emerging Infectious Diseases ,Infectious Diseases ,5.1 Pharmaceuticals ,Aetiology ,2.1 Biological and endogenous factors ,Development of treatments and therapeutic interventions ,Inflammatory and immune system ,Anti-Inflammatory Agents ,Antioxidants ,CD4-Positive T-Lymphocytes ,Cells ,Cultured ,Cytokines ,Dendritic Cells ,Humans ,Iron Compounds ,anti-inflammatory ,CD4+T cells ,dendritic cells ,hydroferrate fluid ,MRN-100 ,CD4+ T cells ,Pharmacology and Pharmaceutical Sciences ,Pharmacology and pharmaceutical sciences - Abstract
The hydroferrate fluid MRN-100, an iron-based compound with potent antioxidant characteristics, was examined to identify its possible anti-inflammatory effects on human dendritic cells (DCs) in vitro. Human monocyte-derived DCs were treated with MRN-100 at two concentrations (50 and 100 μL/mL) for 24 h and then stimulated with or without lipopolysaccharides (LPS). The expression of DC maturation markers was assessed by flow cytometry and the production of cytokines was determined by enzyme-linked immunosorbent assay (ELISA). Functional assay was performed by co-culturing MRN-100-treated and untreated DCs with allogeneic naïve CD4+ T cells and assaying the T cells' cytokine production. Results show that treatment with MRN-100 significantly upregulated the co-stimulatory molecules CD80 and CD86 and increased human leukocyte antigen-DR (HLA-DR) though not significantly. MRN-100 treatment also significantly increased the production of the anti-inflammatory cytokine interleukin (IL)-10. On the other hand, MRN-100 significantly induced the secretion of pro-inflammatory cytokines such as IL-6 only at high concentrations. Furthermore, DCs pretreated with MRN-100 and either stimulated or not with LPS were able to prime CD4+ T cells to secrete significant amounts of IL-10 while inhibiting the secretion of pro-inflammatory cytokine tumor necrosis factor (TNF)-α. These results indicate that MRN-100 is a powerful anti-inflammatory agent that promotes the generation of an anti-inflammatory immune response in vitro. MRN-100 could be beneficial for treating patients with inflammatory diseases, including arthritis and type 1 diabetes, and its potential benefits should be examined in clinical trials.
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- 2019
13. Inhibition of TRPV1 Channel Activity in Human CD4⁺ T Cells by Nanodiamond and Nanoplatinum Liquid, DPV576.
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Ghoneum, Mamdooh H, Gimzewski, James K, Ghoneum, Aya, Katano, Hideki, Paw U, Clarissa Nila, and Agrawal, Anshu
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CD4+ T cells ,TRPV1 ,capsaicin ,nanodiamond ,CD4(+) T cells ,Chronic Pain ,Pain Research ,2.1 Biological and endogenous factors ,Pain Conditions - Chronic ,Materials Engineering ,Nanotechnology - Abstract
Background: Transient receptor potential vanilloid (TRPV) channels act as sensors of pain, temperature, and other external stimuli. We have recently shown that DPV576, an aqueous mixture of nanodiamond (ND) and nanoplatinum (NP), can modulate the activity of TRPV on human primary keratinocytes, suggesting their potential as a possible pain modulator. Here, we sought to examine the effect of DPV576 in modulating the functions of human CD4⁺ T lymphocytes and whether the modulation is mediated via TRPV channels. Materials and methods: Human primary CD4⁺ T cells were activated with anti CD3/CD28 with and without DPV576 at 1:10 and 1:100 dilutions for 24 h in vitro. TRPV receptor expression (TRPV1 and TRPV4) on CD4⁺ T cells were examined by flow cytometry. The capacity of DPV576 to modulate the activity of TRPV1 agonist capsaicin in CD4⁺ T cells was also determined. Activation of CD4⁺ T cells was determined by production of cytokines TNF-α, IFN-γ, and IL-10 using specific ELISA kits. Results: DPV576 treatment of CD4⁺ T cells that were activated with anti CD3/CD28 resulted in decreased expression of the TRPV1 channel, but had no effect on TRPV4. This was accompanied by decreased secretion of IFN-γ and reduced expression of TRPV1 in capsaicin activated CD4⁺ T cells. In addition, DPV576 inhibited the capsaicin, induced the production of IFN-γ, and enhanced the secretion of IL-10. Conclusion: We conclude that short term exposure to DPV576 inhibits the activity of TRPV1 channels in CD4⁺ T lymphocytes, which may suggest its possible beneficial use for pain management.
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- 2018
14. Cancer cell mechanobiology: a new frontier for cancer research
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Yu, Weibo, Sharma, Shivani, Rao, Elizabeth, Rowat, Amy C., Gimzewski, James K., Han, Dong, and Rao, Jianyu
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- 2022
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15. Programmable Fading Memory in Atomic Switch Systems for Error Checking Applications
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Aguilera, Renato, Sillin, Henry O., Stieg, Adam Z., Gimzewski, James K., Bäck, Thomas, Series Editor, Kari, Lila, Series Editor, Nakajima, Kohei, editor, and Fischer, Ingo, editor
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- 2021
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16. Modulation of TRPV1 Function in Human CD4+ T Cells by Nanodiamond and Nanoplatinum Liquid, DPV576
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Ghoneum, Mamdooh H, Gimzewski, James K, Ghoneum, Aya D, Katano, Hideki, and Agrawal, Anshu
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Biomedical and Clinical Sciences ,Clinical Sciences ,Immunology ,Pain Research ,Chronic Pain ,2.1 Biological and endogenous factors ,Aetiology ,Inflammatory and immune system - Abstract
Transient receptor potential vanilloid (TRPV) channels act as sensors of pain, temperature, and other external stimuli. We have recently shown that DPV576, an aqueous mixture of nanodiamond (ND) and nanoplatinum (NP), can modulate the activity of TRPV on human primary keratinocytes, suggesting their potential as a possible pain modulator [1]. CD4+ T lymphocytes also express TRPV channels, and we sought with special interest to examine the effect of DPV576 in modulating the functions of TRPV channel expression and secretion of cytokines on human CD4+ T lymphocytes. Human primary CD4+ T cells were activated with anti CD3/CD28 with and without DPV576 at 1:25 and 1:100 dilutions for 24 hours in vitro. TRPV Receptor expression (TRPV1 and TRPV4) on CD4+ T cells was examined by flow cytometry. The capacity of DPV576 to modulate the activity of TRPV1 agonist capsaicin in CD4+ T cells was also determined. Activation of CD4+ T cells was determined by production of cytokines TNF-α, IFN-γ, and IL-10 using specific ELISA kits. DPV576 treatment of CD4+ T cells that were activated with anti CD3/CD28, resulted in increased expression of TRPV1 channel but had no effect on TRPV4. This was accompanied by increased secretion of IFN-g and reduced expression of TRPV1 in capsaicin activated CD4+ T cells. In addition, DPV576 inhibited the capsaicin, induced the production of both IFN-g and TNF-α, and enhanced the secretion of IL-10. We conclude that short term exposure to DPV576 inhibits the activity of TRPV1 channels in CD4+ T lymphocytes, which may suggest its possible beneficial use for pain management.
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- 2018
17. Marina crystal minerals (MCM) activate human dendritic cells to induce CD4+ and CD8+ T cell responses in vitro.
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Ghoneum, Mamdooh H, Ogura, Takeshi, Gimzewski, James K, Ghoneum, Aya D, Henary, Michael C, and Agrawal, Sudhanshu
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Dendritic Cells ,CD4-Positive T-Lymphocytes ,CD8-Positive T-Lymphocytes ,Cells ,Cultured ,Humans ,Minerals ,Adjuvants ,Immunologic ,HLA-DR Antigens ,Cytokines ,Crystallization ,Coculture Techniques ,Lymphocyte Activation ,Seawater ,Paracrine Communication ,Signal Transduction ,Lysosomal-Associated Membrane Protein 1 ,B7-1 Antigen ,B7-2 Antigen ,CD4+ T cells ,CD8+ T cells ,DCs ,MCM ,CD4+T cells ,CD8+T cells ,Cells ,Cultured ,Adjuvants ,Immunologic ,Pharmacology and Pharmaceutical Sciences ,Immunology - Abstract
Marina crystal minerals (MCM) are a mixture that contains crystallized minerals along with trace elements extracted from seawater. It is a nutritional supplement that is capable of enhancing natural killer (NK) cell activity and increasing T and B cell proliferation in humans post ingestion. However, its effect on dendritic cells (DCs), the cells that bridge innate and adaptive immunity, is not yet known. In this study, we examine the stimulatory effects of MCM on DCs' maturation and function in vitro. Human monocyte-derived DCs were treated with MCM at two different concentrations (10 and 20 µg/mL) for 24 h. Results showed that MCM treatment activated DCs in a dose-dependent fashion. It caused the upregulation of costimulatory molecules CD80, CD86, and HLA-DR, and prompted the production of DC cytokines, including interleukin (IL)-6, IL-10, tumor necrosis factor (TNF)-α, and IL-1β, and chemokines (monocyte chemotactic protein-1 (MCP-1)) and interferon-gamma-inducible protein-10 (IP-10). In addition, activated DCs primed CD4+ T cells to secrete significant amounts of interferon gamma (IFN-γ), and they also stimulated CD8+ T cells to express higher amounts of CD107a. These results indicate that MCM is a potentially powerful adjuvant, from natural materials, that activates human DCs in vitro and therefore may suggest its possible use in immune-based therapies against cancer and viral infections.
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- 2018
18. Glucose inhibits cardiac muscle maturation through nucleotide biosynthesis.
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Nakano, Haruko, Minami, Itsunari, Braas, Daniel, Pappoe, Herman, Wu, Xiuju, Sagadevan, Addelynn, Vergnes, Laurent, Fu, Kai, Morselli, Marco, Dunham, Christopher, Ding, Xueqin, Stieg, Adam Z, Gimzewski, James K, Pellegrini, Matteo, Clark, Peter M, Reue, Karen, Lusis, Aldons J, Ribalet, Bernard, Kurdistani, Siavash K, Christofk, Heather, Nakatsuji, Norio, and Nakano, Atsushi
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Myocardium ,Myocytes ,Cardiac ,Animals ,Mice ,Inbred C57BL ,Humans ,Mice ,Nucleotides ,Glucose ,Sweetening Agents ,Gene Expression Profiling ,Cell Differentiation ,Muscle Development ,Pregnancy ,Female ,Pentose Phosphate Pathway ,Embryonic Stem Cells ,cardiac ,developmental biology ,diabetes ,human ,human pluripotent stem cell ,mouse ,stem cells ,Diabetes ,Cardiovascular ,Pediatric ,Stem Cell Research ,Perinatal Period - Conditions Originating in Perinatal Period ,Conditions Affecting the Embryonic and Fetal Periods ,Nutrition ,Stem Cell Research - Induced Pluripotent Stem Cell - Human ,Heart Disease ,Stem Cell Research - Induced Pluripotent Stem Cell ,2.1 Biological and endogenous factors ,1.1 Normal biological development and functioning ,5.1 Pharmaceuticals ,Reproductive health and childbirth ,Biochemistry and Cell Biology - Abstract
The heart switches its energy substrate from glucose to fatty acids at birth, and maternal hyperglycemia is associated with congenital heart disease. However, little is known about how blood glucose impacts heart formation. Using a chemically defined human pluripotent stem-cell-derived cardiomyocyte differentiation system, we found that high glucose inhibits the maturation of cardiomyocytes at genetic, structural, metabolic, electrophysiological, and biomechanical levels by promoting nucleotide biosynthesis through the pentose phosphate pathway. Blood glucose level in embryos is stable in utero during normal pregnancy, but glucose uptake by fetal cardiac tissue is drastically reduced in late gestational stages. In a murine model of diabetic pregnancy, fetal hearts showed cardiomyopathy with increased mitotic activity and decreased maturity. These data suggest that high glucose suppresses cardiac maturation, providing a possible mechanistic basis for congenital heart disease in diabetic pregnancy.
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- 2017
19. DNA nanomapping using CRISPR-Cas9 as a programmable nanoparticle.
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Mikheikin, Andrey, Olsen, Anita, Leslie, Kevin, Russell-Pavier, Freddie, Yacoot, Andrew, Picco, Loren, Payton, Oliver, Toor, Amir, Chesney, Alden, Gimzewski, James K, Mishra, Bud, and Reed, Jason
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Humans ,Lymphoma ,Follicular ,Translocation ,Genetic ,Proto-Oncogene Proteins c-bcl-2 ,DNA ,Microscopy ,Atomic Force ,Chromosome Mapping ,Genomics ,Nanotechnology ,Image Processing ,Computer-Assisted ,Immunoglobulin Heavy Chains ,Nanoparticles ,High-Throughput Nucleotide Sequencing ,CRISPR-Cas Systems ,Bioengineering ,Biotechnology ,Genetics ,Human Genome ,Lymphoma ,Follicular ,Translocation ,Genetic ,Microscopy ,Atomic Force ,Image Processing ,Computer-Assisted - Abstract
Progress in whole-genome sequencing using short-read (e.g.,
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- 2017
20. Identification of a Human Airway Epithelial Cell Subpopulation with Altered Biophysical, Molecular, and Metastatic Properties
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Pagano, Paul C, Tran, Linh M, Bendris, Nawal, O'Byrne, Sean, Tse, Henry T, Sharma, Shivani, Hoech, Jonathan W, Park, Stacy J, Liclican, Elvira L, Jing, Zhe, Li, Rui, Krysan, Kostyantyn, Paul, Manash K, Fontebasso, Yari, Larsen, Jill E, Hakimi, Shaina, Seki, Atsuko, Fishbein, Michael C, Gimzewski, James K, Carlo, Dino Di, Minna, John D, Walser, Tonya C, and Dubinett, Steven M
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Biomedical and Clinical Sciences ,Clinical Sciences ,Oncology and Carcinogenesis ,Lung Cancer ,Cancer ,Lung ,Clinical Research ,2.1 Biological and endogenous factors ,Aetiology ,Animals ,Bronchi ,Cell Line ,Tumor ,Cell Movement ,Cell Proliferation ,Cell Survival ,Epithelial Cells ,Gene Expression Profiling ,Humans ,Lung Neoplasms ,Mice ,Mice ,Inbred NOD ,Specific Pathogen-Free Organisms ,Xenograft Model Antitumor Assays ,rac1 GTP-Binding Protein ,Oncology & Carcinogenesis ,Clinical sciences ,Oncology and carcinogenesis - Abstract
Lung cancers are documented to have remarkable intratumoral genetic heterogeneity. However, little is known about the heterogeneity of biophysical properties, such as cell motility, and its relationship to early disease pathogenesis and micrometastatic dissemination. In this study, we identified and selected a subpopulation of highly migratory premalignant airway epithelial cells that were observed to migrate through microscale constrictions at up to 100-fold the rate of the unselected immortalized epithelial cell lines. This enhanced migratory capacity was found to be Rac1-dependent and heritable, as evidenced by maintenance of the phenotype through multiple cell divisions continuing more than 8 weeks after selection. The morphology of this lung epithelial subpopulation was characterized by increased cell protrusion intensity. In a murine model of micrometastatic seeding and pulmonary colonization, the motility-selected premalignant cells exhibit both enhanced survival in short-term assays and enhanced outgrowth of premalignant lesions in longer-term assays, thus overcoming important aspects of "metastatic inefficiency." Overall, our findings indicate that among immortalized premalignant airway epithelial cell lines, subpopulations with heritable motility-related biophysical properties exist, and these may explain micrometastatic seeding occurring early in the pathogenesis of lung cancer. Understanding, targeting, and preventing these critical biophysical traits and their underlying molecular mechanisms may provide a new approach to prevent metastatic behavior. Cancer Prev Res; 10(9); 514-24. ©2017 AACRSee related editorial by Hynds and Janes, p. 491.
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- 2017
21. Advanced Interferometry with 3-D Structured Illumination Reveals the Surface Fine Structure of Complex Biospecimens
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Matsuzaki, Takahisa, primary, Kawamura, Ryuzo, additional, Yamamoto, Akihisa, additional, Takahashi, Hozumi, additional, Fujii, Mai, additional, Togo, Shodai, additional, Yoneyama, Yosuke, additional, Hakuno, Fumihiko, additional, Takahashi, Shin-Ichiro, additional, Suganuma, Masami, additional, Nakabayashi, Seiichiro, additional, Sharma, Shivani, additional, Gimzewski, James K., additional, and Yoshikawa, Hiroshi Y., additional
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- 2024
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22. Artificial Synapses Realized by Atomic Switch Technology
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Tsuruoka, Tohru, Ohno, Takeo, Nayak, Alpana, Yang, Rui, Hasegawa, Tsuyoshi, Terabe, Kazuya, Gimzewski, James K., Aono, Masakazu, Joachim, Christian, Series Editor, and Aono, Masakazu, editor
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- 2020
- Full Text
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23. Atomic force microscopy correlates antimetastatic potentials of HepG2 cell line with its redox/energy status: effects of curcumin and Khaya senegalensis
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Olugbami, Jeremiah Olorunjuwon, Damoiseaux, Robert, France, Bryan, Gbadegesin, Michael A, Stieg, Adam Z, Sharma, Shivani, Odunola, Oyeronke A, and Gimzewski, James K
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Health Sciences ,Traditional ,Complementary and Integrative Medicine ,Cancer ,Complementary and Integrative Health ,Adenosine Triphosphate ,Antineoplastic Agents ,Phytogenic ,Apoptosis ,Cell Proliferation ,Curcuma ,Curcumin ,Elasticity ,Glutathione ,Hep G2 Cells ,Humans ,Meliaceae ,Microscopy ,Atomic Force ,Neoplasm Invasiveness ,Neoplasm Metastasis ,Oxidation-Reduction ,Phytotherapy ,Plant Extracts ,Khaya senegalensis ,atomic force microscopy ,glutathione ,adenosine triphosphate ,metasis ,carcinoma ,hepatocellular ,Traditional ,complementary and integrative medicine - Abstract
ObjectiveThe fatality of cancer is mostly dependent on the possibility of occurrence of metastasis. Thus, if the development of metastasis can be prevented through novel therapeutic strategies targeted against this process, then the success of cancer treatment will drastically increase. In this study, therefore, we evaluated the antimetastatic potentials of an extract of Khaya senegalensis and curcumin on the metastatic liver cell line HepG2, and also assessed the anticancer property of the extract.MethodsCells were cultured and treated with graded concentrations of test substances for 24, 48, or 72 h with provisions made for negative controls. Treated cells were assessed as follows: nanotechnologically - atomic force microscopy (AFM) was used to determine cell stiffness; biochemically - cell cytotoxicity, glutathione level and adenosine triphosphate status, caspase activation and mitochondrial toxicity were considered; and microbiologically - a carrot disk assay was used to assess the anticancer property of the extract of K. senegalensis.ResultsCurcumin and K. senegalensis increased the cell stiffness by 2.6- and 4.0-fold respectively, indicating their antimetastatic effects. Corresponding changes in redox (glutathione level) and energy (adenosine triphosphate) status of the cells were also demonstrated. Further mechanistic studies indicated that curcumin was not mitotoxic in HepG2 cells unlike the K. senegalensis extract. In addition, the extract potently inhibited the Agrobacterium tumefaciens-induced genetic transformation based on carrot disk assay.ConclusionCell elasticity measurement data, using AFM, strongly suggested, for the first time, that both curcumin and the extract of K. senegalensis exhibited antimetastatic properties on HepG2 cells.
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- 2017
24. Two dimensional electrophysiological characterization of human pluripotent stem cell-derived cardiomyocyte system.
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Zhu, Huanqi, Scharnhorst, Kelsey S, Stieg, Adam Z, Gimzewski, James K, Minami, Itsunari, Nakatsuji, Norio, Nakano, Haruko, and Nakano, Atsushi
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Myocytes ,Cardiac ,Pluripotent Stem Cells ,Humans ,Cell Culture Techniques ,Cell Differentiation ,Electrophysiological Phenomena ,Myocytes ,Cardiac - Abstract
Stem cell-derived cardiomyocytes provide a promising tool for human developmental biology, regenerative therapies, disease modeling, and drug discovery. As human pluripotent stem cell-derived cardiomyocytes remain functionally fetal-type, close monitoring of electrophysiological maturation is critical for their further application to biology and translation. However, to date, electrophysiological analyses of stem cell-derived cardiomyocytes has largely been limited by biologically undefined factors including 3D nature of embryoid body, sera from animals, and the feeder cells isolated from mouse. Large variability in the aforementioned systems leads to uncontrollable and irreproducible results, making conclusive studies difficult. In this report, a chemically-defined differentiation regimen and a monolayer cell culture technique was combined with multielectrode arrays for accurate, real-time, and flexible measurement of electrophysiological parameters in translation-ready human cardiomyocytes. Consistent with their natural counterpart, amplitude and dV/dtmax of field potential progressively increased during the course of maturation. Monolayer culture allowed for the identification of pacemaking cells using the multielectrode array platform and thereby the estimation of conduction velocity, which gradually increased during the differentiation of cardiomyocytes. Thus, the electrophysiological maturation of the human pluripotent stem cell-derived cardiomyocytes in our system recapitulates in vivo development. This system provides a versatile biological tool to analyze human heart development, disease mechanisms, and the efficacy/toxicity of chemicals.
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- 2017
25. Self-organization and Emergence of Dynamical Structures in Neuromorphic Atomic Switch Networks
- Author
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Stieg, Adam Z., Avizienis, Audrius V., Sillin, Henry O., Aguilera, Renato, Shieh, Hsien-Hang, Martin-Olmos, Cristina, Sandouk, Eric J., Aono, Masakazu, Gimzewski, James K., Chua, Leon, editor, Sirakoulis, Georgios Ch., editor, and Adamatzky, Andrew, editor
- Published
- 2019
- Full Text
- View/download PDF
26. Glucose inhibits cardiac muscle maturation through nucleotide biosynthesis
- Author
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Nakano, Haruko, Minami, Itsunari, Braas, Daniel, Pappoe, Herman, Wu, Xiuju, Sagadevan, Addelynn, Vergnes, Laurent, Fu, Kai, Morselli, Marco, Dunham, Christopher, Ding, Xueqin, Stieg, Adam Z, Gimzewski, James K, Pellegrini, Matteo, Clark, Peter M, Reue, Karen, Lusis, Aldons J, Ribalet, Bernard, Kurdistani, Siavash K, Christofk, Heather, Nakatsuji, Norio, and Nakano, Atsushi
- Subjects
Biochemistry and Cell Biology ,Biomedical and Clinical Sciences ,Biological Sciences ,Cardiovascular Medicine and Haematology ,Reproductive Medicine ,Congenital Structural Anomalies ,Heart Disease ,Diabetes ,Pediatric ,Cardiovascular ,Congenital Heart Disease ,Stem Cell Research - Induced Pluripotent Stem Cell ,Perinatal Period - Conditions Originating in Perinatal Period ,Stem Cell Research ,Rare Diseases ,Stem Cell Research - Induced Pluripotent Stem Cell - Human ,Pregnancy ,Women's Health ,Regenerative Medicine ,5.1 Pharmaceuticals ,1.1 Normal biological development and functioning ,2.1 Biological and endogenous factors ,Reproductive health and childbirth ,Animals ,Cell Differentiation ,Embryonic Stem Cells ,Female ,Gene Expression Profiling ,Glucose ,Humans ,Mice ,Mice ,Inbred C57BL ,Muscle Development ,Myocardium ,Myocytes ,Cardiac ,Nucleotides ,Pentose Phosphate Pathway ,Sweetening Agents ,cardiac ,developmental biology ,diabetes ,human ,human pluripotent stem cell ,mouse ,stem cells ,Biological sciences ,Biomedical and clinical sciences ,Health sciences - Abstract
The heart switches its energy substrate from glucose to fatty acids at birth, and maternal hyperglycemia is associated with congenital heart disease. However, little is known about how blood glucose impacts heart formation. Using a chemically defined human pluripotent stem-cell-derived cardiomyocyte differentiation system, we found that high glucose inhibits the maturation of cardiomyocytes at genetic, structural, metabolic, electrophysiological, and biomechanical levels by promoting nucleotide biosynthesis through the pentose phosphate pathway. Blood glucose level in embryos is stable in utero during normal pregnancy, but glucose uptake by fetal cardiac tissue is drastically reduced in late gestational stages. In a murine model of diabetic pregnancy, fetal hearts showed cardiomyopathy with increased mitotic activity and decreased maturity. These data suggest that high glucose suppresses cardiac maturation, providing a possible mechanistic basis for congenital heart disease in diabetic pregnancy.
- Published
- 2016
27. Thermodynamic Self Assembly of Two-Dimensional pi-Conjugated Metal-Porphyrin Covalent Organic Frameworks by On-Site Equilibrium Polymerization
- Author
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Tanoue, Ryota, Higuchi, Rintaro, Ikebe, Kiryu, Uemura, Shinobu, Kimizuka, Nobuo, Stieg, Adam Z., Gimzewski, James K., and Kunitake, Masashi
- Subjects
Condensed Matter - Materials Science - Abstract
Two dimensional pi conjugated metal porphyrin covalent organic frameworks were produced in aqueous solution on an iodine-modified Au(111) surface by on site azomethine coupling of Fe(III) 5,10,15,20 tetrakis(4 aminophenyl)porphyrin (FeTAPP) with terephthal dicarboxaldehyde and investigated in detail using in-situ scanning tunneling microscopy. Mixed covalent organic porphyrin frameworks consisting of FeTAPP and metal-free TAPP (H2TAPP) were prepared through simultaneous adsorption in a mixed solution as well as partial replacement of FeTAPP by H2TAPP in an as prepared metal porphyrin framework. In the mixed framework, the relative distribution of FeTAPP to H2TAPP was not random and revealed a preference for homo-connection rather than heteroconnection. The construction of substrate-supported, pi conjugated covalent frameworks from multiple building blocks, including metal centers, will be of significant utility in the design of functional molecular nanoarchitectures., Comment: 7 pages, 5 figures
- Published
- 2013
- Full Text
- View/download PDF
28. Multistate resistive switching in silver nanoparticle films.
- Author
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Sandouk, Eric J, Gimzewski, James K, and Stieg, Adam Z
- Subjects
memory ,nanomaterials ,resistive switching ,Materials ,Condensed Matter Physics ,Optical Physics ,Materials Engineering - Abstract
Resistive switching devices have garnered significant consideration for their potential use in nanoelectronics and non-volatile memory applications. Here we investigate the nonlinear current-voltage behavior and resistive switching properties of composite nanoparticle films comprising a large collective of metal-insulator-metal junctions. Silver nanoparticles prepared via the polyol process and coated with an insulating polymer layer of tetraethylene glycol were deposited onto silicon oxide substrates. Activation required a forming step achieved through application of a bias voltage. Once activated, the nanoparticle films exhibited controllable resistive switching between multiple discrete low resistance states that depended on operational parameters including the applied bias voltage, temperature and sweep frequency. The films' resistance switching behavior is shown here to be the result of nanofilament formation due to formative electromigration effects. Because of their tunable and distinct resistance states, scalability and ease of fabrication, nanoparticle films have a potential place in memory technology as resistive random access memory cells.
- Published
- 2015
29. Mitochondrial Ca(2+) uptake by the voltage-dependent anion channel 2 regulates cardiac rhythmicity.
- Author
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Shimizu, Hirohito, Schredelseker, Johann, Huang, Jie, Lu, Kui, Naghdi, Shamim, Lu, Fei, Franklin, Sarah, Fiji, Hannah Dg, Wang, Kevin, Zhu, Huanqi, Tian, Cheng, Lin, Billy, Nakano, Haruko, Ehrlich, Amy, Nakai, Junichi, Stieg, Adam Z, Gimzewski, James K, Nakano, Atsushi, Goldhaber, Joshua I, Vondriska, Thomas M, Hajnóczky, György, Kwon, Ohyun, and Chen, Jau-Nian
- Subjects
Heart ,Mitochondria ,Myocytes ,Cardiac ,Animals ,Zebrafish ,Calcium ,Zebrafish Proteins ,Calcium Signaling ,Amino Acid Sequence ,Heart Rate ,Myocardial Contraction ,Video Recording ,Molecular Sequence Data ,Voltage-Dependent Anion Channel 2 ,Embryo ,Mammalian ,VDAC ,arrhythmia ,calcium handling ,cell biology ,developmental biology ,fibrillation ,heart ,human ,mitochondria ,mouse ,stem cells ,zebrafish ,Myocytes ,Cardiac ,Embryo ,Mammalian ,Cardiovascular ,Heart Disease ,2.1 Biological and endogenous factors ,5.1 Pharmaceuticals ,Biochemistry and Cell Biology - Abstract
Tightly regulated Ca(2+) homeostasis is a prerequisite for proper cardiac function. To dissect the regulatory network of cardiac Ca(2+) handling, we performed a chemical suppressor screen on zebrafish tremblor embryos, which suffer from Ca(2+) extrusion defects. Efsevin was identified based on its potent activity to restore coordinated contractions in tremblor. We show that efsevin binds to VDAC2, potentiates mitochondrial Ca(2+) uptake and accelerates the transfer of Ca(2+) from intracellular stores into mitochondria. In cardiomyocytes, efsevin restricts the temporal and spatial boundaries of Ca(2+) sparks and thereby inhibits Ca(2+) overload-induced erratic Ca(2+) waves and irregular contractions. We further show that overexpression of VDAC2 recapitulates the suppressive effect of efsevin on tremblor embryos whereas VDAC2 deficiency attenuates efsevin's rescue effect and that VDAC2 functions synergistically with MCU to suppress cardiac fibrillation in tremblor. Together, these findings demonstrate a critical modulatory role for VDAC2-dependent mitochondrial Ca(2+) uptake in the regulation of cardiac rhythmicity.
- Published
- 2015
30. Benchtop Fabrication of Memristive Atomic Switch Networks
- Author
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Sillin, Henry O., Sandouk, Eric J., Avizienis, Audrius V., Aono, Masakazu, Stieg, Adam Z., and Gimzewski, James K.
- Subjects
Condensed Matter - Materials Science ,Condensed Matter - Disordered Systems and Neural Networks - Abstract
Recent advances in nanoscale science and technology provide possibilities to directly self-assemble and integrate functional circuit elements within the wiring scheme of devices with potentially unique architectures. Electroionic resistive switching circuits comprising highly interconnected fractal electrodes and metal-insulator-metal interfaces, known as atomic switch networks, have been fabricated using simple benchtop techniques including solution-phase electroless deposition. These devices are shown to activate through a bias-induced forming step that produces the frequency dependent, nonlinear hysteretic switching expected for gapless-type atomic switches and memristors. By eliminating the need for complex lithographic methods, such an approach toward device fabrication provides a more accessible platform for the study of ionic resistive switches and memristive systems., Comment: 8 pages, 8 figures
- Published
- 2013
- Full Text
- View/download PDF
31. Nanomechanical Analysis of Cells from Cancer Patients
- Author
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Cross, Sarah E., primary, Jin, Yu-Sheng, additional, Rao, Jianyu, additional, and Gimzewski, James K., additional
- Published
- 2020
- Full Text
- View/download PDF
32. Nanostructured Self-Assembly of Inverted Formin 2 (INF2) and F‑Actin–INF2 Complexes Revealed by Atomic Force Microscopy
- Author
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Sharma, Shivani, Grintsevich, Elena E, Woo, JungReem, Gurel, Pinar S, Higgs, Henry N, Reisler, Emil, and Gimzewski, James K
- Subjects
Actins ,Microfilament Proteins ,Microscopy ,Atomic Force ,Protein Binding ,Chemical Physics - Abstract
Self-organization of cytoskeletal proteins such as actin and tubulin into filaments and microtubules is frequently assisted by the proteins binding to them. Formins are regulatory proteins that nucleate the formation of new filaments and are essential for a wide range of cellular functions. The vertebrate inverted formin 2 (INF2) has both actin filament nucleating and severing/depolymerizing activities connected to its ability to encircle actin filaments. Using atomic force microscopy, we report that a formin homology 2 (FH2) domain-containing construct of INF2 (INF2-FH1-FH2-C or INF2-FFC) self-assembles into nanoscale ringlike oligomeric structures in the absence of actin filaments, demonstrating an inherent ability to reorganize from a dimeric to an oligomeric state. A construct lacking the C-terminal region (INF2-FH1-FH2 or INF2-FF) also oligomerizes, confirming the dominant role of FH2-mediated interactions. Moreover, INF2-FFC domains were observed to organize into ringlike structures around single actin filaments. This is the first demonstration that formin FH2 domains can self-assemble into oligomers in the absence of filaments and has important implications for observing unaveraged decoration and/or remodeling of filaments by actin binding proteins.
- Published
- 2014
33. Atomic Force Microscopic Detection Enabling Multiplexed Low-Cycle-Number Quantitative Polymerase Chain Reaction for Biomarker Assays
- Author
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Mikheikin, Andrey, Olsen, Anita, Leslie, Kevin, Mishra, Bud, Gimzewski, James K, and Reed, Jason
- Subjects
Biotechnology ,Detection ,screening and diagnosis ,4.1 Discovery and preclinical testing of markers and technologies ,Gene Expression ,Humans ,Microscopy ,Atomic Force ,Multiplex Polymerase Chain Reaction ,RNA ,Analytical Chemistry ,Other Chemical Sciences - Abstract
Quantitative polymerase chain reaction is the current "golden standard" for quantification of nucleic acids; however, its utility is constrained by an inability to easily and reliably detect multiple targets in a single reaction. We have successfully overcome this problem with a novel combination of two widely used approaches: target-specific multiplex amplification with 15 cycles of polymerase chain reaction (PCR), followed by single-molecule detection of amplicons with atomic force microscopy (AFM). In test experiments comparing the relative expression of ten transcripts in two different human total RNA samples, we find good agreement between our single reaction, multiplexed PCR/AFM data, and data from 20 individual singleplex quantitative PCR reactions. This technique can be applied to virtually any analytical problem requiring sensitive measurement concentrations of multiple nucleic acid targets.
- Published
- 2014
34. Nanofilaments on glioblastoma exosomes revealed by peak force microscopy
- Author
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Sharma, Shivani, Das, Kingshuk, Woo, JungReem, and Gimzewski, James K
- Subjects
Cancer ,Brain Cancer ,Brain Disorders ,Rare Diseases ,Biomechanical Phenomena ,Biophysics ,Cell Communication ,Cell Line ,Tumor ,Cytoskeleton ,Exosomes ,Glioblastoma ,Humans ,Microscopy ,Atomic Force ,Models ,Biological ,nanoparticles ,glioblastoma exosomes ,nanofilaments ,intercellular communication ,nanotechnology ,General Science & Technology - Abstract
Exosomes are sub-100 nm extracellular vesicles secreted by normal and cancer cells. We present a high-resolution structure of previously unidentified nanofilaments on glioblastoma-derived exosomes, using nanoscale peak force imaging. These stiff, adhesive, trypsin- and RNAse-resistant surface nanofilaments add a new dimension to the current structural knowledge of exosome-mediated intercellular communication.
- Published
- 2014
35. Artificial Synapses Realized by Atomic Switch Technology
- Author
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Tsuruoka, Tohru, primary, Ohno, Takeo, additional, Nayak, Alpana, additional, Yang, Rui, additional, Hasegawa, Tsuyoshi, additional, Terabe, Kazuya, additional, Gimzewski, James K., additional, and Aono, Masakazu, additional
- Published
- 2020
- Full Text
- View/download PDF
36. Rigid microenvironments promote cardiac differentiation of mouse and human embryonic stem cells.
- Author
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Arshi, Armin, Nakashima, Yasuhiro, Nakano, Haruko, Eaimkhong, Sarayoot, Evseenko, Denis, Reed, Jason, Stieg, Adam Z, Gimzewski, James K, and Nakano, Atsushi
- Subjects
Cardiac Differentiation ,Drug-selected cardiomyocyte ,Matrix elasticity ,Mechanical interferometry ,Pluripotent Embryonic Stem Cell ,Synchronization ,cardiac differentiation pluripotent embryonic stem cell matrix elasticity ,drug-selected cardiomyocyte ,synchronization ,mechanical interferometry ,Materials ,Condensed Matter Physics ,Optical Physics ,Materials Engineering - Abstract
While adult heart muscle is the least regenerative of tissues, embryonic cardiomyocytes are proliferative, with embryonic stem (ES) cells providing an endless reservoir. In addition to secreted factors and cell-cell interactions, the extracellular microenvironment has been shown to play an important role in stem cell lineage specification, and understanding how scaffold elasticity influences cardiac differentiation is crucial to cardiac tissue engineering. Though previous studies have analyzed the role of the matrix elasticity on the function of differentiated cardiomyocytes, whether it affects the induction of cardiomyocytes from pluripotent stem cells is poorly understood. Here, we examined the role of matrix rigidity on the cardiac differentiation using mouse and human ES cells. Culture on polydimethylsiloxane (PDMS) substrates of varied monomer-to-crosslinker ratios revealed that rigid extracellular matrices promote a higher yield of de novo cardiomyocytes from undifferentiated ES cells. Using an genetically modified ES system that allows us to purify differentiated cardiomyocytes by drug selection, we demonstrate that rigid environments induce higher cardiac troponin T expression, beating rate of foci, and expression ratio of adult α- to fetal β- myosin heavy chain in a purified cardiac population. M-mode and mechanical interferometry image analyses demonstrate that these ES-derived cardiomyocytes display functional maturity and synchronization of beating when co-cultured with neonatal cardiomyocytes harvested from a developing embryo. Together, these data identify matrix stiffness as an independent factor that instructs not only the maturation of the already differentiated cardiomyocytes but also the induction and proliferation of cardiomyocytes from undifferentiated progenitors. Manipulation of the stiffness will help direct the production of functional cardiomyocytes en masse from stem cells for regenerative medicine purposes.
- Published
- 2013
37. DNA builds and strengthens the extracellular matrix in Myxococcus xanthus biofilms by interacting with exopolysaccharides.
- Author
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Hu, Wei, Li, Lina, Sharma, Shivani, Wang, Jing, McHardy, Ian, Lux, Renate, Yang, Zhe, He, Xuesong, Gimzewski, James K, Li, Yuezhong, and Shi, Wenyuan
- Subjects
Cell Membrane ,Chromosomes ,Bacterial ,Extracellular Matrix ,Biofilms ,Myxococcus xanthus ,Polysaccharides ,DNA ,Bacterial ,Microscopy ,Confocal ,Chromosomes ,Bacterial ,DNA ,Microscopy ,Confocal ,General Science & Technology - Abstract
One intriguing discovery in modern microbiology is the extensive presence of extracellular DNA (eDNA) within biofilms of various bacterial species. Although several biological functions have been suggested for eDNA, including involvement in biofilm formation, the detailed mechanism of eDNA integration into biofilm architecture is still poorly understood. In the biofilms formed by Myxococcus xanthus, a Gram-negative soil bacterium with complex morphogenesis and social behaviors, DNA was found within both extracted and native extracellular matrices (ECM). Further examination revealed that these eDNA molecules formed well organized structures that were similar in appearance to the organization of exopolysaccharides (EPS) in ECM. Biochemical and image analyses confirmed that eDNA bound to and colocalized with EPS within the ECM of starvation biofilms and fruiting bodies. In addition, ECM containing eDNA exhibited greater physical strength and biological stress resistance compared to DNase I treated ECM. Taken together, these findings demonstrate that DNA interacts with EPS and strengthens biofilm structures in M. xanthus.
- Published
- 2012
38. Neuromorphic atomic switch networks.
- Author
-
Avizienis, Audrius V, Sillin, Henry O, Martin-Olmos, Cristina, Shieh, Hsien Hang, Aono, Masakazu, Stieg, Adam Z, and Gimzewski, James K
- Subjects
Humans ,Neurosciences ,Electricity ,Models ,Neurological ,Computers ,Neural Networks ,Computer ,Models ,Neurological ,Neural Networks ,Computer ,General Science & Technology - Abstract
Efforts to emulate the formidable information processing capabilities of the brain through neuromorphic engineering have been bolstered by recent progress in the fabrication of nonlinear, nanoscale circuit elements that exhibit synapse-like operational characteristics. However, conventional fabrication techniques are unable to efficiently generate structures with the highly complex interconnectivity found in biological neuronal networks. Here we demonstrate the physical realization of a self-assembled neuromorphic device which implements basic concepts of systems neuroscience through a hardware-based platform comprised of over a billion interconnected atomic-switch inorganic synapses embedded in a complex network of silver nanowires. Observations of network activation and passive harmonic generation demonstrate a collective response to input stimulus in agreement with recent theoretical predictions. Further, emergent behaviors unique to the complex network of atomic switches and akin to brain function are observed, namely spatially distributed memory, recurrent dynamics and the activation of feedforward subnetworks. These devices display the functional characteristics required for implementing unconventional, biologically and neurally inspired computational methodologies in a synthetic experimental system.
- Published
- 2012
39. Nanoscale Visualization and Characterization of Myxococcus xanthus Cells with Atomic Force Microscopy
- Author
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Pelling, Andrew E., Li, Yinuo, Shi, Wenyuan, Gimzewski, James K., and Quate, Calvin F.
- Published
- 2005
40. Nanocharacterization in dentistry.
- Author
-
Sharma, Shivani, Cross, Sarah E, Hsueh, Carlin, Wali, Ruseen P, Stieg, Adam Z, and Gimzewski, James K
- Subjects
Cell Wall ,Cytoplasmic Vesicles ,Dental Plaque ,Dental Enamel ,Dentin ,Humans ,Biofilms ,Streptococcus mutans ,Mouth Neoplasms ,Tooth Demineralization ,Bacterial Proteins ,Biocompatible Materials ,Dental Implants ,Anti-Infective Agents ,Microscopy ,Atomic Force ,Dentistry ,Bacterial Adhesion ,Mutation ,Nanotechnology ,Biomarkers ,afm ,bacterial adhesins ,biofilms ,dentine tubule ,dentistry ,implants ,interferometry ,nano-characterization ,nanodentistry ,Biological Markers ,Microscopy ,Atomic Force ,Other Chemical Sciences ,Genetics ,Other Biological Sciences ,Chemical Physics - Abstract
About 80% of US adults have some form of dental disease. There are a variety of new dental products available, ranging from implants to oral hygiene products that rely on nanoscale properties. Here, the application of AFM (Atomic Force Microscopy) and optical interferometry to a range of dentistry issues, including characterization of dental enamel, oral bacteria, biofilms and the role of surface proteins in biochemical and nanomechanical properties of bacterial adhesins, is reviewed. We also include studies of new products blocking dentine tubules to alleviate hypersensitivity; antimicrobial effects of mouthwash and characterizing nanoparticle coated dental implants. An outlook on future "nanodentistry" developments such as saliva exosomes based diagnostics, designing biocompatible, antimicrobial dental implants and personalized dental healthcare is presented.
- Published
- 2010
41. Local Nanomechanical Motion of the Cell Wall of Saccharomyces cerevisiae
- Author
-
Pelling, Andrew E., Sehati, Sadaf, Gralla, Edith B., Valentine, Joan S., and Gimzewski, James K.
- Published
- 2004
42. Data from Identification of a Human Airway Epithelial Cell Subpopulation with Altered Biophysical, Molecular, and Metastatic Properties
- Author
-
Pagano, Paul C., primary, Tran, Linh M., primary, Bendris, Nawal, primary, O'Byrne, Sean, primary, Tse, Henry T., primary, Sharma, Shivani, primary, Hoech, Jonathan W., primary, Park, Stacy J., primary, Liclican, Elvira L., primary, Jing, Zhe, primary, Li, Rui, primary, Krysan, Kostyantyn, primary, Paul, Manash K., primary, Fontebasso, Yari, primary, Larsen, Jill E., primary, Hakimi, Shaina, primary, Seki, Atsuko, primary, Fishbein, Michael C., primary, Gimzewski, James K., primary, Carlo, Dino Di, primary, Minna, John D., primary, Walser, Tonya C., primary, and Dubinett, Steven M., primary
- Published
- 2023
- Full Text
- View/download PDF
43. Tables S1-5, Figures S1-S6, 3 Methods from Identification of a Human Airway Epithelial Cell Subpopulation with Altered Biophysical, Molecular, and Metastatic Properties
- Author
-
Pagano, Paul C., primary, Tran, Linh M., primary, Bendris, Nawal, primary, O'Byrne, Sean, primary, Tse, Henry T., primary, Sharma, Shivani, primary, Hoech, Jonathan W., primary, Park, Stacy J., primary, Liclican, Elvira L., primary, Jing, Zhe, primary, Li, Rui, primary, Krysan, Kostyantyn, primary, Paul, Manash K., primary, Fontebasso, Yari, primary, Larsen, Jill E., primary, Hakimi, Shaina, primary, Seki, Atsuko, primary, Fishbein, Michael C., primary, Gimzewski, James K., primary, Carlo, Dino Di, primary, Minna, John D., primary, Walser, Tonya C., primary, and Dubinett, Steven M., primary
- Published
- 2023
- Full Text
- View/download PDF
44. Self-Organization and Emergence of Dynamic Systems
- Author
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Gimzewski, James K., Stieg, Adam Z., Vesna, Victoria, Bainbridge, William Sims, editor, and Roco, Mihail C., editor
- Published
- 2016
- Full Text
- View/download PDF
45. Atomic Force Microscopy for Medicine
- Author
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Sharma, Shivani, primary and Gimzewski, James K., additional
- Published
- 2019
- Full Text
- View/download PDF
46. Nanoscale Science of Single Molecules Using Local Probes
- Author
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Gimzewski, James K. and Joachim, Christian
- Published
- 1999
47. Surface Stress in the Self-Assembly of Alkanethiols on Gold
- Author
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Berger, Rüdiger, Delamarche, Emmanuel, Lang, Hans Peter, Gerber, Christoph, Gimzewski, James K., Meyer, Ernst, and Güntherodt, Hans-Joachim
- Published
- 1997
48. Self-organization and Emergence of Dynamical Structures in Neuromorphic Atomic Switch Networks
- Author
-
Stieg, Adam Z., Avizienis, Audrius V., Sillin, Henry O., Aguilera, Renato, Shieh, Hsien-Hang, Martin-Olmos, Cristina, Sandouk, Eric J., Aono, Masakazu, Gimzewski, James K., Adamatzky, Andrew, editor, and Chua, Leon, editor
- Published
- 2014
- Full Text
- View/download PDF
49. Fine Needle Elastography (FNE) device for biomechanically determining local variations of tissue mechanical properties
- Author
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Wickramaratne, Dayan, Wilkinson, Paul, Rao, JianYu, Ragavendra, Nagesh, Sharma, Shivani, and Gimzewski, James K.
- Published
- 2015
- Full Text
- View/download PDF
50. Optimizing Methods for ICP-MS Analysis of Mercury in Fish: An Upper-Division Analytical Chemistry Laboratory Class
- Author
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Jung, Wonhyeuk, primary, Dunham, Christopher S., additional, Perrotta, Katie A., additional, Chen, Yu, additional, Gimzewski, James K., additional, and Loo, Joseph A., additional
- Published
- 2022
- Full Text
- View/download PDF
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