196,015 research outputs found
Interactions Between 2D Graphene-Based Materials and the Nervous Tissue
No full textIn recent years, the scientific community has witnessed an exponential increase in the use of graphene for biomedical applications. For what concerns neuroscience, the interest raised by this material is given by the fact that graphene nanosheets can be used as carriers for biomolecule delivery to the central nervous system. In this case, an important aspect is the evaluation of their toxicity, which strongly depends on flake composition, chemical functionalization and dimensions. Furthermore, graphene can be exploited as a substrate for tissue engineering. In this application, conductivity is probably the most relevant amongst the various properties of the different graphene materials, as it may allow to instruct and interrogate neural networks, as well as to drive neural growth and differentiation.
This chapter discusses the engineering of graphene nanosheets able to cross the blood-brain-barrier to reach neural cells, and to achieve on-demand delivery of specific drugs. Moreover, the use of graphene to develop three-dimensional scaffolds, or as a component of hybrid composites/multi-layer organic electronics devices, is described. The need of an accurate theoretical modeling of the interface between graphene and biological material is also addressed, by describing the interaction of graphene with proteins and cell membranes at the nanoscale
Interactions Between 2D Graphene-Based Materials and the Nervous Tissue
No full textIn recent years, the scientific community has witnessed an exponential increase in the use of graphene for biomedical applications. For what concerns neuroscience, the interest raised by this material is given by the fact that graphene nanosheets can be used as carriers for biomolecule delivery to the central nervous system. In this case, an important aspect is the evaluation of their toxicity, which strongly depends on flake composition, chemical functionalization and dimensions. Furthermore, graphene can be exploited as a substrate for tissue engineering. In this application, conductivity is probably the most relevant amongst the various properties of the different graphene materials, as it may allow to instruct and interrogate neural networks, as well as to drive neural growth and differentiation.
This chapter discusses the engineering of graphene nanosheets able to cross the blood-brain-barrier to reach neural cells, and to achieve on-demand delivery of specific drugs. Moreover, the use of graphene to develop three-dimensional scaffolds, or as a component of hybrid composites/multi-layer organic electronics devices, is described. The need of an accurate theoretical modeling of the interface between graphene and biological material is also addressed, by describing the interaction of graphene with proteins and cell membranes at the nanoscale
Interfacing Graphene-Based Materials With Neural Cells
No full textThe scientific community has witnessed an exponential increase in the applications of graphene and graphene-based materials in a wide range of fields, from engineering to electronics to biotechnologies and biomedical applications. For what concerns neuroscience, the interest raised by these materials is two-fold. On one side, nanosheets made of graphene or graphene derivatives (graphene oxide, or its reduced form) can be used as carriers for drug delivery. Here, an important aspect is to evaluate their toxicity, which strongly depends on flake composition, chemical functionalization and dimensions. On the other side, graphene can be exploited as a substrate for tissue engineering. In this case, conductivity is probably the most relevant amongst the various properties of the different graphene materials, as it may allow to instruct and interrogate neural networks, as well as to drive neural growth and differentiation, which holds a great potential in regenerative medicine. In this review, we try to give a comprehensive view of the accomplishments and new challenges of the field, as well as which in our view are the most exciting directions to take in the immediate future. These include the need to engineer multifunctional nanoparticles (NPs) able to cross the blood-brain-barrier to reach neural cells, and to achieve on-demand delivery of specific drugs. We describe the state-of-the-art in the use of graphene materials to engineer three-dimensional scaffolds to drive neuronal growth and regeneration in vivo, and the possibility of using graphene as a component of hybrid composites/multi-layer organic electronics devices. Last but not least, we address the need of an accurate theoretical modeling of the interface between graphene and biological material, by modeling the interaction of graphene with proteins and cell membranes at the nanoscale, and describing the physical mechanism(s) of charge transfer by which the various graphene materials can influence the excitability and physiology of neural cells
Graphene nanoplatelets render poly(3-hydroxybutyrate) a suitable scaffold to promote neuronal network development
No full textThe use of composite biomaterials as innovative bio-friendly neuronal interfaces has been poorly developed so far. Smart strategies to target neuro-pathologies are currently exploiting the mixed and complementary characteristics of composite materials to better design future neural interfaces. Here we present a polymer-based scaffold that has been rendered suitable for primary neurons by embedding graphene nanoplatelets (GnP). In particular, the growth, network formation, and functionality of primary neurons on poly(3-hydroxybutyrate) [P(3HB)] polymer supports functionalized with various concentrations of GnP were explored. After growing primary cortical neurons onto the supports for 14 days, all specimens were found to be biocompatible, revealing physiological growth and maturation of the neuronal network. When network functionality was investigated by whole patch-clamp measurements, pure P(3HB) led to changes in the action potential waveform and reduction in firing frequency, resulting in decreased neuronal excitability. However, the addition of GnP to the polymer matrix restored the electrophysiological parameters to physiological values. Interestingly, a low concentration of graphene was able to promote firing activity at a low level of injected current. The results indicate that the P(3HB)/GnP composites show great potential for electrical interfacing with primary neurons to eventually target central nervous system disorders
Dr. Duane M. Jackson, Morehouse College, July 2011
No full textThis video is a conversation with Dr. Duane M. Jackson. Dr. Jackson talks about his paper, "Recall and the Serial Position Effect: The Role of Primacy and Recency on Accounting Students' Performance." Jackie Daniel, AUC Woodruff Library, is the interviewer
"Reflections on the subject of Emigration from Europe with a view to Settlement in the United States" By M. Carey.
No full text"Reflections on the subject of Emigration from Europe with a view to Settlement in the United States: containing bried sketches of the moral and political character of those states.
By M. Carey, member of the American philosophical, and of the American Antiquarian Society, and author of The Olive Branch, Cindiciae Hibernicae, essays on banking, on political economy, and on internal improvement.
To which are now added the English editor's comments on the subject; together with Important Advice to Emigrants, and Cautions Against Impositions Practiced in the Outports
Dispelling the Myths Behind First-author Citation Counts
No full textWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
Dr. Glendon Swarthout
No full textHosted by Roger M. Busfield, MSU Assistant Professor of Speech and Theater, Meet the Author is designed to introduce a general audience to a contemporary author and their work through in-depth interviews. This episode features a conversation between Dr. Glendon Swarthout, prolific author and English professor at MSU, and assistant professors Sam S. Baskett and Theodore B. Strandness
Multidisciplinary screening of toxicity induced by silica nanoparticles during sea urchin development
No full textThe aim of this study was to investigate the potential toxicity of Silica nanoparticles (SiO2 NPs) in seawater
by using the sea urchin Paracentrotus lividus as biological model. SiO2 NPs exposure effects were identified
on the sperm of the sea urchin through a multidisciplinary approach, combining developmental
biology, ecotoxicology, biochemistry, and microscopy analyses. The following responses were measured:
(i) percentage of eggs fertilized by exposed sperm; (ii) percentage of anomalies and undeveloped
embryos and larvae; (iii) enzyme activity alterations (acetylcholinesterase, AChE) in the early developmental
stages, namely gastrula and pluteus. Sperms were exposed to seawater containing SiO2 NPs suspensions
ranging from 0.0001 mg/L to 50 mg/L. Fertilization ability was not affected at any concentration,
whereas a significant percentage of anomalies in the offspring were observed and quantified by means of
EC50 at gastrula stage, including undeveloped and anomalous embryos (EC50 = 0.06 mg/L), and at pluteus
stage, including skeletal anomalies and delayed larvae (EC50 = 0.27 mg/L). Moreover, morphological
anomalies were observed in larvae at pluteus stage, by immunolocalizing molecules involved in larval
development and neurotoxicity effects – such as acetylated tubulin and choline acetyltransferase
(ChAT) – and measuring AChE activity. Exposure of sea urchins to SiO2 NPs caused neurotoxic damage
and a decrease of AChE expression in a non-dose-dependent manner.
In conclusion, through the multidisciplinary approach used in this study SiO2 NPs toxicity in sea urchin
offspring could be assessed. Therefore, the measured responses are suitable for detecting embryo- and
larval- toxicity induced by these NPs
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