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Development Of Non-Covalent Functionalization Of Carbon Nanotubes For Sirna Delivery, King Sun Siu 2014 The University of Western Ontario

Development Of Non-Covalent Functionalization Of Carbon Nanotubes For Sirna Delivery, King Sun Siu

Electronic Thesis and Dissertation Repository

RNA interference (RNAi) therapy is promising for treating various diseases but the delivery of small interfering RNA (siRNA) is difficult. To overcome the technical difficulties of siRNA delivery, an efficient and targeted delivery of siRNA is required for efficient RNAi therapy. Single-walled carbon nanotubes (CNT) has been used for nucleic acid delivery such as siRNA delivery. It has been found that CNT can gain entry into the cells by a diffusion-like mechanism which was called “nano-needle”. However, the solubility of CNT is low in most of the solvents including water. Functionalization of CNT can be carried out to enhance the …


A Backing Device Based On An Embedded Stiffener And Retractable Insertion Tool For Thin-Film Cochlear Arrays, Radheshyam Tewari 2014 Michigan Technological University

A Backing Device Based On An Embedded Stiffener And Retractable Insertion Tool For Thin-Film Cochlear Arrays, Radheshyam Tewari

Dissertations, Master's Theses and Master's Reports - Open

Intracochlear trauma from surgical insertion of bulky electrode arrays and inadequate pitch perception are areas of concern with current hand-assembled commercial cochlear implants. Parylene thin-film arrays with higher electrode densities and lower profiles are a potential solution, but lack rigidity and hence depend on manually fabricated permanently attached polyethylene terephthalate (PET) tubing based bulky backing devices. As a solution, we investigated a new backing device with two sub-systems. The first sub-system is a thin poly(lactic acid) (PLA) stiffener that will be embedded in the parylene array. The second sub-system is an attaching and detaching mechanism, utilizing a poly(N-vinylpyrrolidone)-block-poly(d,l-lactide) (PVP-b-PDLLA) copolymer-based …


Therapeutic Efficacy Of Cerium Oxide Nanoparticles Against Sepsis Induced Multi-Organ Dysfunction Syndrome In Sprague Dawley Rats, Nandini Durga Prasanna Kumar Manne 2014 Marshall University

Therapeutic Efficacy Of Cerium Oxide Nanoparticles Against Sepsis Induced Multi-Organ Dysfunction Syndrome In Sprague Dawley Rats, Nandini Durga Prasanna Kumar Manne

Theses, Dissertations and Capstones

Sepsis is a generalized term that signifies the presence of a pathogen in the blood stream to which the body responds by eliciting a systemic inflammatory response. Although sepsis is the leading cause of death in non-coronary intensive care units in United States, there are currently no FDA approved therapeutic drugs to treat this disorder. Cerium oxide nanoparticles (CeO2) have been shown to exhibit anti-oxidant, anti-inflammatory, and anti-bacterial properties both in vitro and in vivo. Whether CeO2 nanoparticles can be used for the treatment of sepsis is currently unclear.

To investigate whether CeO2 nanoparticles can …


Dr. Who?: The Science And Culture Of Medical Wear Design, Patricia Duignan 2014 Virginia Commonwealth University

Dr. Who?: The Science And Culture Of Medical Wear Design, Patricia Duignan

Theses and Dissertations

The multi-million-dollar medical uniform industry has not utilized advancements in garment and textile technology that could positively impact the protection of healthcare professionals and patients. In most cases the uniforms meet basic requirements – they clothe the professional in a recognizable way. Little innovation in design, function and performance, has been applied to these garments. This is particularly evident in the case of the stereotypical white lab coat worn by many physicians, despite evidence indicating that these lab coats may carry contamination and play a role in the spread of deadly bacteria. Healthcare Associated Infections (HAIs) are among the most …


Modified Seed Growth Of Iron Oxide Nanoparticles In Benzyl Alcohol: Magnetic Nanoparticles For Radio Frequency Hyperthermia Treatment Of Cancer, Stanley E. Gilliland III 2014 Virginia Commonwealth University

Modified Seed Growth Of Iron Oxide Nanoparticles In Benzyl Alcohol: Magnetic Nanoparticles For Radio Frequency Hyperthermia Treatment Of Cancer, Stanley E. Gilliland Iii

Theses and Dissertations

Iron oxide nanoparticles have received sustained interest for biomedical applications as synthetic approaches are continually developed for precise control of nanoparticle properties. This thesis presents an investigation of parameters in the benzyl alcohol synthesis of iron oxide nanoparticles. A modified seed growth method was designed for obtaining optimal nanoparticle properties for magnetic fluid hyperthermia. With a one or two addition process, iron oxide nanoparticles were produced with crystallite sizes ranging from 5-20 nm using only benzyl alcohol and iron precursor. The effects of reaction environment, temperature, concentration, and modified seed growth parameters were investigated to obtain precise control over properties …


Self-Assembly Of Peptides To Nanostructures, Dindyal Mandal, Amir Nasrolahi Shirazi, Keykavous Parang 2014 KIIT University

Self-Assembly Of Peptides To Nanostructures, Dindyal Mandal, Amir Nasrolahi Shirazi, Keykavous Parang

Pharmacy Faculty Articles and Research

The formation of well-ordered nanostructures through self-assembly of diverse organic and inorganic building blocks has drawn much attention owing to their potential applications in biology and chemistry. Among all organic building blocks, peptides are one of the most promising platforms due to their biocompatibility, chemical diversity, and resemblance with proteins. Inspired from the protein assembly in biological systems, various self-assembled peptide structures have been constructed using several amino acids and sequences. This review focuses on this emerging area, the recent advances in peptide self-assembly, and formation of different nanostructures, such as tubular, fibers, vesicles, spherical, and rod coil structures. While …


In Vitro Analysis Of Nanoparticulate Hydroxyapatite/Chitosan Composites As Potential Drug Delivery Platforms For The Sustained Release Of Antibiotics In The Treatment Of Osteomyelitis, Vuk Uskoković, Tejal A. Dasai 2014 Chapman University

In Vitro Analysis Of Nanoparticulate Hydroxyapatite/Chitosan Composites As Potential Drug Delivery Platforms For The Sustained Release Of Antibiotics In The Treatment Of Osteomyelitis, Vuk Uskoković, Tejal A. Dasai

Pharmacy Faculty Articles and Research

Nanoparticulate composites of hydroxyapatite (HAp) and chitosan were synthesized by ultrasound-assisted sequential precipitation and characterized for their microstructure at the atomic scale, surface charge, drug release properties, and combined antibacterial and osteogenic response. Crystallinity of HAp nanoparticles was reduced because of the interference of the surface layers of chitosan with the dissolution/reprecipitation-mediated recrystallization mechanism that conditions the transition from the as-precipitated amorphous calcium phosphate phase to the most thermodynamically stable one—HAp. Embedment of 5–10 nm sized, narrowly dispersed HAp nanoparticles within the polymeric matrix mitigated the burst release of the small molecule model drug, fluorescein, bound to HAp by physisorption, …


Simultaneous Bactericidal And Osteogenic Effect Of Nanoparticulate Calcium Phosphate Powders Loaded With Clindamycin On Osteoblasts Infected With Staphylococcus Aureus, Vuk Uskoković, Tejal A. Dasai 2014 Chapman University

Simultaneous Bactericidal And Osteogenic Effect Of Nanoparticulate Calcium Phosphate Powders Loaded With Clindamycin On Osteoblasts Infected With Staphylococcus Aureus, Vuk Uskoković, Tejal A. Dasai

Pharmacy Faculty Articles and Research

S aureus internalized by bone cells and shielded from the immune system provides a reservoir of bacteria in recurring osteomyelitis. Its targeting by the antibiotic therapy may thus be more relevant for treating chronic bone infection than eliminating only the pathogens colonizing the bone matrix. Assessed was the combined osteogenic and antibacterial effect of clindamycinloaded calcium phosphate nanoparticles of different monophasic compositions on co-cultures comprising osteoblasts infected with S aureus. Antibiotic-carrying particles were internalized by osteoblasts and minimized the concentration of intracellular bacteria. In vitro treatments of the infected cells, however, could not prevent cell necrosis due to the …


Nanoparticulate Drug Delivery Platforms For Advancing Bone Infection Therapies, Vuk Uskoković, Tejal A. Dasai 2014 Chapman University

Nanoparticulate Drug Delivery Platforms For Advancing Bone Infection Therapies, Vuk Uskoković, Tejal A. Dasai

Pharmacy Faculty Articles and Research

Introduction—The ongoing surge of resistance of bacterial pathogens to antibiotic therapies and the consistently aging median member of the human race signal an impending increase in the incidence of chronic bone infection. Nanotechnological platforms for local and sustained delivery of therapeutics hold the greatest potential for providing minimally invasive and maximally regenerative therapies for this rare but persistent condition.

Areas covered—Shortcomings of the clinically available treatment options, including poly(methyl methacrylate) beads and calcium sulfate cements, are discussed and their transcending using calcium-phosphate/polymeric nanoparticulate composites is foreseen. Bone is a composite wherein the weakness of each component alone is …


Amphiphilic Triazolyl Peptides: Synthesis And Evaluation As Nanostructures, Naser Sayeh, Amir Nasrolahi Shirazi, Donghoon Oh, Jiadong Sun, David Rowley, Antara Banerjee, Arpita Yadav, Rakesh Tiwari, Keykavous Parang 2014 University of Rhode Island

Amphiphilic Triazolyl Peptides: Synthesis And Evaluation As Nanostructures, Naser Sayeh, Amir Nasrolahi Shirazi, Donghoon Oh, Jiadong Sun, David Rowley, Antara Banerjee, Arpita Yadav, Rakesh Tiwari, Keykavous Parang

Pharmacy Faculty Articles and Research

A new class of amphiphilic triazolyl peptides was designed and synthesized from peptide-based building blocks containing alkyne and azide functional groups namely linear (W(pG))3, cyclic[W(pG)]3, and Ac-K(N3)R-NH2,where W, R, K, and pG represent tryptophan, arginine, lysine, and propargylglycine residues, respectively. The linear (W(pG))3 and cyclic [W(pG)]3 peptides containing alkyne residues were conjugated with Ac-K(N3)R-NH2 functionalized with azide group through click chemistry in the presence of CuSO4.5H2O, Cu (powder), sodium ascorbate, and N,N-disopropylethylamine in methanol:water to afford amphiphilic triazolyl linear-linear (WG(triazole-KR-NH2))3 and cyclic-linear [WG(triazole-KR-NH2)]3 peptides, respectively. The secondary structures of both peptides were similar to a distorted α-helix as shown by …


Bovine Serum Albumin (Bsa) And Cleaved-Bsa Conjugated Ultrasmallgd2o3nanoparticles: Synthesis, Characterization, And Application To Mri Contrast Agents, Md Wasi Ahmad, Cho Rong Kim, Jong Su Baeck, Yongmin Chang, Tae Jeong Kim, Ji Eun Bae, Kwon Seok Chae, Gang Ho Lee 2013 Kyungpook National University

Bovine Serum Albumin (Bsa) And Cleaved-Bsa Conjugated Ultrasmallgd2o3nanoparticles: Synthesis, Characterization, And Application To Mri Contrast Agents, Md Wasi Ahmad, Cho Rong Kim, Jong Su Baeck, Yongmin Chang, Tae Jeong Kim, Ji Eun Bae, Kwon Seok Chae, Gang Ho Lee

Dr. Mohammad Wasi Ahmad (Md Wasi Ahmad)

No abstract provided.


Hybrid Nanostructured Textile Bioelectrode For Unobtrusive Health Monitoring, Pratyush Rai 2013 University of Arkansas, Fayetteville

Hybrid Nanostructured Textile Bioelectrode For Unobtrusive Health Monitoring, Pratyush Rai

Graduate Theses and Dissertations

Coronary heart disease, cardiovascular diseases and strokes are the leading causes of mortality in United States of America. Timely point-of-care health diagnostics and therapeutics for person suffering from these diseases can save thousands of lives. However, lack of accessible minimally intrusive health monitoring systems makes timely diagnosis difficult and sometimes impossible. To remedy this problem, a textile based nano-bio-sensor was developed and evaluated in this research. The sensor was made of novel array of vertically standing nanostructures that are conductive nano-fibers projecting from a conductive fabric. These sensor electrodes were tested for the quality of electrical contact that they made …


Combination Of Sirna-Directed Gene Silencing With Cisplatin Reverses Drug Resistance In Human Non-Small Cell Lung Cancer, Shanthi Ganesh, Arun K. Iyer, Jan Weller, David V. Morrissey, Mansoor M. Amiji 2013 Northeastern University

Combination Of Sirna-Directed Gene Silencing With Cisplatin Reverses Drug Resistance In Human Non-Small Cell Lung Cancer, Shanthi Ganesh, Arun K. Iyer, Jan Weller, David V. Morrissey, Mansoor M. Amiji

Pharmaceutical Sciences Faculty Publications

One of the most challenging aspects of lung cancer therapy is the rapid acquisition of multidrug-resistant (MDR) phenotype. One effective approach would be to identify and downregulate resistance-causing genes in tumors using small interfering RNAs (siRNAs) to increase the sensitivity of tumor cells to chemotherapeutic challenge. After identifying the overexpressed resistance-related antiapoptotic genes (survivin and bcl-2) in cisplatin-resistant cells, the siRNA sequences were designed and screened to select the most efficacious candidates. Modifications were introduced in them to minimize off-target effects. Subsequently, the combination of siRNA and cisplatin that gave the maximum synergy was identified in resistant cells. We then …


Design And Fabrication Of Nanofluidic Systems With Integrated Sensing Electrodes For Rapid Biomolecule Characterization, Taylor Bradley Busch 2013 University of Arkansas, Fayetteville

Design And Fabrication Of Nanofluidic Systems With Integrated Sensing Electrodes For Rapid Biomolecule Characterization, Taylor Bradley Busch

Graduate Theses and Dissertations

A transparent nanofluidic system with embedded sensing electrodes was designed and fabricated by integrating Atomic Force Microscopy (AFM) nanolithography, Focused Ion Beam (FIB) milling and metal deposition, and standard microfabrication processing. The fabrication process started with the evaporation of chrome/gold (Cr/Au) onto a Pyrex 7740 wafer followed by photolithography and wet etching of the microchannels. The wafer was patterned a second time to form Au microelectrodes with 15-45 micrometer separation gaps in the nanochannel region. Sensing electrodes (up to one micron wide) were then deposited using FIB to bridge the gaps. The nanochannels were realized through both AFM nanolithography and …


Synthesis And Assembly Of Dihydroindolizines On Gold Surfaces For Light Induced Work Function Alterations, Matthew Alan Bartucci 2013 Loyola University Chicago

Synthesis And Assembly Of Dihydroindolizines On Gold Surfaces For Light Induced Work Function Alterations, Matthew Alan Bartucci

Dissertations

Taking advantage of surfaces' response to interfacial dipoles, a class of photochromophores (dihydroindolizine) is demonstrated to alter the work function of the underlying substrate (170 meV). This same molecule also provides spectroscopic signatures for correlating the change in molecular structure to the induced change in the surfaces' electronic properties. Polarization modulation infrared reflection absorption spectroscopy (PM-IRRAS) allows analysis of the characteristic dihydroindolizine C=C (1559 cm-1) and pyridinium (1643 cm-1) stretch as a function of photoexcitation. Structural assignments of this photochromophore are corroborated to density function theory calculations. Conformational changes in the monolayers appear in parallel with work function changes and …


Generation Of Intracellular Reactive Oxygen Species And Genotixity Effect To Exposure Of Nanosized Polyamidoamine (Pamam) Dendrimers In Plhc-1 Cells In Vitro, Pratap Naha, Hugh Byrne 2013 University of Pennsylvania

Generation Of Intracellular Reactive Oxygen Species And Genotixity Effect To Exposure Of Nanosized Polyamidoamine (Pamam) Dendrimers In Plhc-1 Cells In Vitro, Pratap Naha, Hugh Byrne

Articles

Polyamidoamine (PAMAM) dendrimers elicit systematically variable cyto- and eco-toxic responses, promising the basis for structure activity relationships governing nanotoxicological responses. Increased production of intracellular reactive oxygen species (ROS), genotoxicity and apoptosis due to in-vitro exposure of hepatocellular carcinoma cells to dendrimer generations G-4, G-5 and G-6 is demonstrated. A generation dependent increase in ROS and genotoxicity was observed, consistent with our previous studies. The responses correlate well with the number of surface amino groups per generation. Although ROS production initially increases approximately linearly, it saturates at higher doses. Notably, normalised to molar dose of surface amino groups, the dose-dependent ROS …


Toxicological Effects Of Cerium Oxide Nanoparticle Aggregates On Caenorhabditis Elegans, Steven N. Rogers 2013 Marshall University

Toxicological Effects Of Cerium Oxide Nanoparticle Aggregates On Caenorhabditis Elegans, Steven N. Rogers

Theses, Dissertations and Capstones

Assessing the toxicity and unique reactivity of nanoparticles in biological systems has become an relevant and quickly growing area of environmental toxicology research. The broad use of nanoparticles in industrial and commercial commodities results in exposure of these nano-compounds to the environment, the ecosystems, and humans. While previous data has suggested that cerium oxide (CeO2) nanoparticles are relatively safe to cultured cells much less is known about the potential toxicity of these materials at the organismal level. In this study we employed transgenic Caenorhabditis elegans (C. elegans) strains to assess the toxicity of CeO2 nanoparticles under “real-world” …


Atomic Force Microscopy Characterization Of Collagen ‘Nanostraws’ In Human Costal Cartilage, Michael W. Stacey, Diganta Dutta, Anthony Asmar, H. Elsayed-Ali, R. Kelly Jr., A. Beskok 2013 Old Dominion University

Atomic Force Microscopy Characterization Of Collagen ‘Nanostraws’ In Human Costal Cartilage, Michael W. Stacey, Diganta Dutta, Anthony Asmar, H. Elsayed-Ali, R. Kelly Jr., A. Beskok

Bioelectrics Publications

Costal cartilage, a type of hyaline cartilage that bridges the bony ribs and sternum, is relatively understudied compared to the load bearing cartilages. Deformities of costal cartilage can result in deformation of the chest wall, where the sternum is largely pushed toward or away from the spine, pectus excavatum and pectus carinatum, respectively, with each condition having significant clinical impact. In the absence of extensive literature describing morphological features of costal cartilage, we characterized a sample from the costal margin immunohistologically and through atomic force microscopy. We had previously observed the presence of collagen ‘nanostraws’ running the length of costal …


Cell Responses Without Receptors And Ligands, Using Nanosecond Pulsed Electric Fields (Nspefs), Stephen J. Beebe 2013 Old Dominion University

Cell Responses Without Receptors And Ligands, Using Nanosecond Pulsed Electric Fields (Nspefs), Stephen J. Beebe

Bioelectrics Publications

No abstract provided.


Bioelectrics In Basic Science And Medicine: Impact Of Electric Fields On Cellular Structures And Functions, Stephen J. Beebe 2013 Old Dominion University

Bioelectrics In Basic Science And Medicine: Impact Of Electric Fields On Cellular Structures And Functions, Stephen J. Beebe

Bioelectrics Publications

Bioelectrics is a new interdisciplinary field that investigates electric field effects on cell membranes and other cellular components. It incorporates four main technologies, including electroporation, nanosecond pulsed electric fields, picosecond pulsed electric fields and cold plasmas. The parent technology in Bioelectrics is electroporation, which uses milli- and/or micro-second electric pulses to permeabilize cells and tissues, for delivery of membrane impermeable molecules. It is now being used for electro-gene delivery, with vascular endothelial growth factor, for revascularization in wound healing and cardiovascular and peripheral vascular disease. Plasmids expressing IL-12 are being delivered for immune system activation in melanoma treatment, now in …


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