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Full-Text Articles in Chemistry

Catechin And Other Catechol-Containing Secondary Metabolites: Bacterial Biotransformation And Regulation Of Carbohydrate Metabolism, Sara Knezevic, Asma Ghafoor, Samaneh Mehri, Ali Barazi, Maksymilian Dziura, John F. Trant, Christopher A. Dieni Sep 2021

Catechin And Other Catechol-Containing Secondary Metabolites: Bacterial Biotransformation And Regulation Of Carbohydrate Metabolism, Sara Knezevic, Asma Ghafoor, Samaneh Mehri, Ali Barazi, Maksymilian Dziura, John F. Trant, Christopher A. Dieni

Chemistry and Biochemistry Publications

Background: Catechol, 1,2-dihydroxybenzene, prepared through bacterial biotransformation from higher order polyphenols, has been proposed to regulate carbohydrate metabolism, especially in the context of type 2 diabetes. This review aims to contextualize this finding. It describes the bacterial biosynthesis of catechol both from glucose, and as a degradation product of higher order natural products through bacterial transformation. The review then considers the mechanism of action of glycemic-regulating catechol-containing materials and the complications arising from balancing their inherent activity with that of catechol, their common degradation product. It then enumerates potential dietary sources of catechin from common foods. Methods: Articles were found …


The Formation Of Benzoxacin-3-Ones Via Intramolecular Nicholas Reactions And Synthesis Of 8-Membered Heliannuols, Brent St. Onge, James R. Green Aug 2021

The Formation Of Benzoxacin-3-Ones Via Intramolecular Nicholas Reactions And Synthesis Of 8-Membered Heliannuols, Brent St. Onge, James R. Green

Chemistry and Biochemistry Publications

The γ-carbonyl cations generated from propargyl ether-Co2(CO)6 complexes undergo intramolecular Nicholas reactions to give dehydrobenzoxacin-3-one-Co2(CO)6 complexes in good yields. Reductive decomplexation and subsequent manipulation allows the synthesis of (±)-heliannuol K methyl ether and the formal syntheses of (±)-heliannuol K, (±)-heliannuol A, and (−)-heliannuol L.


Simulated Breathing: Application Of Molecular Dynamics Simulations To Pulmonary Lung Surfactant, Maksymilian Dziura, Basel Mansour, Mitchell Dipasquale, P. Charukeshi Chandrasekera, James W. Gauld, Drew Marquardt Jul 2021

Simulated Breathing: Application Of Molecular Dynamics Simulations To Pulmonary Lung Surfactant, Maksymilian Dziura, Basel Mansour, Mitchell Dipasquale, P. Charukeshi Chandrasekera, James W. Gauld, Drew Marquardt

Chemistry and Biochemistry Publications

In this review, we delve into the topic of the pulmonary surfactant (PS) system, which is present in the respiratory system. The total composition of the PS has been presented and explored, from the types of cells involved in its synthesis and secretion, down to the specific building blocks used, such as the various lipid and protein components. The lipid and protein composition varies across species and between individuals, but ultimately produces a PS monolayer with the same role. As such, the composition has been investigated for the ways in which it imposes function and confers peculiar biophysical characteristics to …


Ready-To-Wear Strain Sensing Gloves For Human Motion Sensing, Sara S. Mechael, Yunyun Wu, Yiting Chen, Tricia Breen Carmichael Jun 2021

Ready-To-Wear Strain Sensing Gloves For Human Motion Sensing, Sara S. Mechael, Yunyun Wu, Yiting Chen, Tricia Breen Carmichael

Chemistry and Biochemistry Publications

Integrating soft sensors with wearable platforms is critical for sensor-based human augmentation, yet the fabrication of wearable sensors integrated into ready-to-wear platforms remains underdeveloped. Disposable gloves are an ideal substrate for wearable sensors that map hand-specific gestures. Here, we use solution-based metallization to prepare resistive sensing arrays directly on off-the-shelf nitrile butadiene rubber (NBR) gloves. The NBR glove acts as the wearable platform while its surface roughness enhances the sensitivity of the overlying sensing array. The NBR sensors have a sheet resistance of 3.1 ± 0.6 Ω/sq and a large linear working range (two linear regions ≤70%). When stretched, the …


Fragment-Based In Silico Design Of Sars-Cov-2 Main Protease Inhibitors, Sarfraz Ahmad, Muhammad Usman Mirza, Lee Yean Kee, Mamoona Nazir, Noorsaadah Abd Rahman, John F. Trant, Iskandar Abdullah Jun 2021

Fragment-Based In Silico Design Of Sars-Cov-2 Main Protease Inhibitors, Sarfraz Ahmad, Muhammad Usman Mirza, Lee Yean Kee, Mamoona Nazir, Noorsaadah Abd Rahman, John F. Trant, Iskandar Abdullah

Chemistry and Biochemistry Publications

3CLpro is essential for SARS-CoV-2 replication and infection; its inhibition using small molecules is a potential therapeutic strategy. In this study, a comprehensive crystallography-guided fragment-based drug discovery approach was employed to design new inhibitors for SARS-CoV-2 3CLpro. All small molecules co-crystallized with SARS-CoV-2 3CLpro with structures deposited in the Protein Data Bank were used as inputs. Fragments sitting in the binding pocket (87) were grouped into eight geographical types. They were interactively coupled using various synthetically reasonable linkers to generate larger molecules with divalent binding modes taking advantage of two different fragments' interactions. In total, 1,251 compounds were proposed, and …


Propargyl Radicals In Organic Synthesis, Marcus Muresan, Hariharaputhiran Subramanian, Mukund P. Sibi, James R. Green Jun 2021

Propargyl Radicals In Organic Synthesis, Marcus Muresan, Hariharaputhiran Subramanian, Mukund P. Sibi, James R. Green

Chemistry and Biochemistry Publications

The appearance of propargyl radicals as synthetic intermediates has increased in recent years from a structural curiosity to a frequent occurrence. This minireview covers the synthetically relevant organic chemistry involving the intermediacy of propargyl radicals. The review is organized by the process employed in radical generation, including H-atom abstraction, propargyl-X homolyses, radical addition to enynes, reduction of polar C=X bonds, reductions of stable carbocations, and metal-mediated coupling reactions. The relevant mechanisms of generation and reaction are discussed, as are applications in syntheses of target molecules of interest.


The 2021 Flexible And Printed Electronics Roadmap, Yvan Bonnassieux, Christoph J. Brabec, Yong Cao, Tricia Breen Carmichael, Michael L. Chabinyc, Kwang Ting Cheng, Gyoujin Cho, Anjung Chung, Corie L. Cobb, Andreas Distler, Hans Joachim Egelhaaf, Gerd Grau, Xiaojun Guo, Ghazaleh Haghiashtiani, Tsung Ching Huang, Muhammad M. Hussain, Benjamin Iniguez, Taik Min Lee, Ling Li, Yuguang Ma, Dongge Ma, Michael C. Mcalpine, Tse Nga Ng, Ronald Österbacka Jun 2021

The 2021 Flexible And Printed Electronics Roadmap, Yvan Bonnassieux, Christoph J. Brabec, Yong Cao, Tricia Breen Carmichael, Michael L. Chabinyc, Kwang Ting Cheng, Gyoujin Cho, Anjung Chung, Corie L. Cobb, Andreas Distler, Hans Joachim Egelhaaf, Gerd Grau, Xiaojun Guo, Ghazaleh Haghiashtiani, Tsung Ching Huang, Muhammad M. Hussain, Benjamin Iniguez, Taik Min Lee, Ling Li, Yuguang Ma, Dongge Ma, Michael C. Mcalpine, Tse Nga Ng, Ronald Österbacka

Chemistry and Biochemistry Publications

This roadmap includes the perspectives and visions of leading researchers in the key areas of flexible and printable electronics. The covered topics are broadly organized by the device technologies (sections 1–9), fabrication techniques (sections 10–12), and design and modeling approaches (sections 13 and 14) essential to the future development of new applications leveraging flexible electronics (FE). The interdisciplinary nature of this field involves everything from fundamental scientific discoveries to engineering challenges; from design and synthesis of new materials via novel device design to modelling and digital manufacturing of integrated systems. As such, this roadmap aims to serve as a resource …


Conducting Materials As Building Blocks For Electronic Textiles, Anja Lund, Yunyun Wu, Benji Fenech-Salerno, Felice Torrisi, Tricia Breen Carmichael, Christian Müller Jun 2021

Conducting Materials As Building Blocks For Electronic Textiles, Anja Lund, Yunyun Wu, Benji Fenech-Salerno, Felice Torrisi, Tricia Breen Carmichael, Christian Müller

Chemistry and Biochemistry Publications

Abstract: To realize the full gamut of functions that are envisaged for electronic textiles (e-textiles) a range of semiconducting, conducting and electrochemically active materials are needed. This article will discuss how metals, conducting polymers, carbon nanotubes, and two-dimensional (2D) materials, including graphene and MXenes, can be used in concert to create e-textile materials, from fibers and yarns to patterned fabrics. Many of the most promising architectures utilize several classes of materials (e.g., elastic fibers composed of a conducting material and a stretchable polymer, or textile devices constructed with conducting polymers or 2D materials and metal electrodes). While an increasing number …


A Concise Synthesis Of A Methyl Ester 2-Resorcinarene: A Chair-Conformation Macrocycle, Michael R. Reynolds, Fraser S. Pick, John J. Hayward, John F. Trant Apr 2021

A Concise Synthesis Of A Methyl Ester 2-Resorcinarene: A Chair-Conformation Macrocycle, Michael R. Reynolds, Fraser S. Pick, John J. Hayward, John F. Trant

Chemistry and Biochemistry Publications

Anions are important hydrogen bond acceptors in a range of biological, chemical, environ-mental and medical molecular recognition processes. These interactions have been exploited for the design and synthesis of ditopic resorcinarenes as the hydrogen bond strength can be tuned through the modification of the substituent at the 2-position. However, many potentially useful compounds, especially those incorporating electron-withdrawing functionalities, have not been prepared due to the challenge of their synthesis: their incorporation slows resorcinarene formation that is accessed by electrophilic aromatic substitution. As part of our broader campaign to employ resorcinarenes as selective recognition elements, we need access to these specialized …


A Dft Study Of The Adsorption Of Deep Eutectic Solvents Onto Graphene And Defective Graphene Nanoflakes, Mehdi Shakourian-Fard, S. Maryamdokht Taimoory, Hamid Reza Ghenaatian, Ganesh Kamath, John F. Trant Apr 2021

A Dft Study Of The Adsorption Of Deep Eutectic Solvents Onto Graphene And Defective Graphene Nanoflakes, Mehdi Shakourian-Fard, S. Maryamdokht Taimoory, Hamid Reza Ghenaatian, Ganesh Kamath, John F. Trant

Chemistry and Biochemistry Publications

The interaction of four deep choline chloride-derived eutectic solvents (DESs) with both graphene nanoflakes (GNF) and its defective double-vacancy and Stone–Wales forms (DV-GNF and SW-GNF), was evaluated using density functional theory (DFT). The presence of defects increases the adsorption energy of DESs, following the order DES∩DV-GNF > DES∩SW-GNF > DES∩GNF. Non-covalent interaction and energy decomposition analyses show that the interactions are noncovalent and dominated by dispersive forces. Furthermore, we find that the presence of aromatic moieties in the DESs increases the van der Waals interactions with the surfaces. These interactions decrease the HOMO-LUMO (Eg) energy gap of the surfaces and thus increase …


Carbon Dots For Specific “Off-On” Sensing Of Co2+ And Edta For In Vivo Bioimaging, Xiangping Wen, Guangming Wen, Wenyan Li, Zhonghua Zhao, Xine Duan, Wenjun Yan, John F. Trant, Yingqi Li Apr 2021

Carbon Dots For Specific “Off-On” Sensing Of Co2+ And Edta For In Vivo Bioimaging, Xiangping Wen, Guangming Wen, Wenyan Li, Zhonghua Zhao, Xine Duan, Wenjun Yan, John F. Trant, Yingqi Li

Chemistry and Biochemistry Publications

Fluorescent carbon dots (CDs) were hydrothermally synthesized from a mixture of frozen tofu, ethylenediamine and phosphoric acid in an efficient 64% yield. The resulting CDs exhibit good water solubility, low cytotoxicity, high stability, and excellent biocompatibility. The CDs selectively and sensitively detect Co2+ through fluorescent quenching with a detection limit of 58 nM. Fluorescence can be restored through the introduction of EDTA, and this phenomenon can be used to quantify EDTA in solution with a detection limit of 98 nM. As both analytes are detected by the same CD platform, this is an “off-on” fluorescence sensor for Co2+ and EDTA. …


The Biosynthesis Of The Cannabinoids, M. Nazir Tahir, Fred Shahbazi, Simon Rondeau-Gagne, John F. Trant Mar 2021

The Biosynthesis Of The Cannabinoids, M. Nazir Tahir, Fred Shahbazi, Simon Rondeau-Gagne, John F. Trant

Chemistry and Biochemistry Publications

Cannabis has been integral to Eurasian civilization for millennia, but a century of prohibition has limited investigation. With spreading legalization, science is pivoting to study the pharmacopeia of the cannabinoids, and a thorough understanding of their biosynthesis is required to engineer strains with specific cannabinoid profiles. This review surveys the biosynthesis and biochemistry of cannabinoids. The pathways and the enzymes’ mechanisms of action are discussed as is the non-enzymatic decarboxylation of the cannabinoic acids. There are still many gaps in our knowledge about the biosynthesis of the cannabinoids, especially for the minor components, and this review highlights the tools and …


Not-So-Innocent Anions Determine The Mechanism Of Cationic Alkylators, S. Maryamdokht Taimoory, Vincenzo Alessandro Cataldo, Andreas Schäfer, John F. Trant, Ryan Guterman Feb 2021

Not-So-Innocent Anions Determine The Mechanism Of Cationic Alkylators, S. Maryamdokht Taimoory, Vincenzo Alessandro Cataldo, Andreas Schäfer, John F. Trant, Ryan Guterman

Chemistry and Biochemistry Publications

Alkylating reagents based on thioimidazolium ionic liquids were synthesized and the influence of the anion on the alkylation reaction mechanism explored in detail using both experimental and computational methods. Thioimidazolium cations transfer alkyl substituents to nucleophiles, however the reaction rate was highly dependent on anion identity, demonstrating that the anion is not innocent in the mechanism. Detailed analysis of the computationally-derived potential energy surfaces associated with possible mechanisms indicated that this dependence arises from a combination of anion induced electronic, steric and coordinating effects, with highly nucleophilic anions catalyzing a 2-step process while highly non-nucleophilic, delocalized anions favor a 1-step …


Time-Resolved Sans Reveals Pore-Forming Peptides Cause Rapid Lipid Reorganization, Michael H.L. Nguyen, Mitchell Dipasquale, Brett W. Rickeard, Caesar G. Yip, Kaity N. Greco, Elizabeth G. Kelley, Drew Marquardt Jan 2021

Time-Resolved Sans Reveals Pore-Forming Peptides Cause Rapid Lipid Reorganization, Michael H.L. Nguyen, Mitchell Dipasquale, Brett W. Rickeard, Caesar G. Yip, Kaity N. Greco, Elizabeth G. Kelley, Drew Marquardt

Chemistry and Biochemistry Publications

Cells depend on proper lipid transport and their precise distribution for vital cellular function. Disruption of such lipid organization can be initiated by external agents to cause cell death. Here, we investigate two antimicrobial pore-forming peptides, alamethicin and melittin, and their influence on lipid intervesicular exchange and transverse lipid diffusion (i.e. flip-flop) in model lipid vesicles. Small angle neutron scattering (SANS) and a strategic contrast matching scheme show the mixing of two isotopically distinct dimyristoylphosphocholine (DMPC) vesicle populations is promoted upon the addition of high (1/40) and low (1/150, 1/1000) peptide-to-lipid (P/L) molar ratios. Parsing out the individual exchange and …


A Prototype Compact Accelerator-Based Neutron Source (Cans) For Canada, Robert Laxdal, Dalini D. Maharaj, Mina Abbaslou, Zin Tun, Daniel Banks, Alexander Gottberg, Marco Marchetto, Eduardo Rodriguez, Zahra Yamani, Helmut Fritzsche, Ronald Rogge, Ming Pan, Oliver Kester, Drew Marquardt Jan 2021

A Prototype Compact Accelerator-Based Neutron Source (Cans) For Canada, Robert Laxdal, Dalini D. Maharaj, Mina Abbaslou, Zin Tun, Daniel Banks, Alexander Gottberg, Marco Marchetto, Eduardo Rodriguez, Zahra Yamani, Helmut Fritzsche, Ronald Rogge, Ming Pan, Oliver Kester, Drew Marquardt

Chemistry and Biochemistry Publications

Canada's access to neutron beams for neutron scattering was significantly curtailed in 2018 with the closure of the National Research Universal (NRU) reactor in Chalk River, Ontario, Canada. New sources are needed for the long-term; otherwise, access will only become harder as the global supply shrinks. Compact Accelerator-based Neutron Sources (CANS) offer the possibility of an intense source of neutrons with a capital cost significantly lower than spallation sources. In this paper, we propose a CANS for Canada. The proposal is staged with the first stage offering a medium neutron flux, linear accelerator-based approach for neutron scattering that is also …


Acid-Triggered Self-Assembled Egg White Protein-Coated Gold Nanoclusters For Selective Fluorescent Detection Of Fe3+, No2-, And Cysteine, Wenyan Li, Xiangping Wen, Hemiao Zhao, Wenjun Yan, John F. Trant, Yingqi Li Dec 2020

Acid-Triggered Self-Assembled Egg White Protein-Coated Gold Nanoclusters For Selective Fluorescent Detection Of Fe3+, No2-, And Cysteine, Wenyan Li, Xiangping Wen, Hemiao Zhao, Wenjun Yan, John F. Trant, Yingqi Li

Chemistry and Biochemistry Publications

Herein, we present a simple and economical synthesis for the first multianalyte probe able to selectively quantify the concentrations of Fe3+, NO2-, and cysteine. It comprises H+-triggered self-assembled gold nanoclusters (AuNCs@EW/H+, AuEHs), showing enhanced red fluorescence at 640 nm. The AuEH is a good fluorescent nanosensor for Fe3+ and NO2- with detection limits of 1.40 and 2.82 nM, respectively. Iron detection, through fluorescence quenching, occurs because of nanocluster aggregation elicited by the complexation of Fe3+ with amino acids on the surface of AuEH; nitrite detection likely proceeds through fluorescence quenching via the disassembly of the nanoclusters following irreversible oxidation by …


An In Silico Approach To Enzymatic Synthesis Of Fucooligosaccharides Using Α-L-Fucosidase From Thermotoga Maritima, Emmanuel Pérez-Escalante, Luis Guillermo González-Olivares, Araceli Castañeda-Ovando, Alma Elizabeth Cruz-Guerrero, John F. Trant, Wendolyne López-Orozco, Luis Humberto Mendoza-Huizar, Sergio Alatorre-Santamaría Nov 2020

An In Silico Approach To Enzymatic Synthesis Of Fucooligosaccharides Using Α-L-Fucosidase From Thermotoga Maritima, Emmanuel Pérez-Escalante, Luis Guillermo González-Olivares, Araceli Castañeda-Ovando, Alma Elizabeth Cruz-Guerrero, John F. Trant, Wendolyne López-Orozco, Luis Humberto Mendoza-Huizar, Sergio Alatorre-Santamaría

Chemistry and Biochemistry Publications

Abstract: Fucooligosaccharides comprise the primary group of human milk oligosaccharides. Due to their beneficial properties, a series of synthetic methods have been proposed to obtain them. Enzy- matic methods show great promise, and α-L-fucosidase from Thermotoga maritima has emerged as a powerful catalyst for their production. Nonetheless, the enzyme’s limited substrate scope has de- layed its wider application. The present work aims to compare the relative reactivity of fucose, pNP-fucose, and ethyl-fucose, while also exploring the molecular interactions of these fucosyl-donors with the enzyme through a combination DFT and docking analysis. The HOMO-LUMO band gaps range from −7.14571 to −4.24429 …


A Mechanical Mechanism For Vitamin E Acetate In E-Cigarette/Vaping-Associated Lung Injury, Mitchell Dipasquale, Omotayo Gbadamosi, Michael H.L. Nguyen, Stuart R. Castillo, Brett W. Rickeard, Elizabeth G. Kelley, Michihiro Nagao, Drew Marquardt Sep 2020

A Mechanical Mechanism For Vitamin E Acetate In E-Cigarette/Vaping-Associated Lung Injury, Mitchell Dipasquale, Omotayo Gbadamosi, Michael H.L. Nguyen, Stuart R. Castillo, Brett W. Rickeard, Elizabeth G. Kelley, Michihiro Nagao, Drew Marquardt

Chemistry and Biochemistry Publications

Copyright © 2020 American Chemical Society. The outbreak of electronic-cigarette/vaping-Associated lung injury (EVALI) has made thousands ill. This lung injury has been attributed to a physical interaction between toxicants from the vaping solution and the pulmonary surfactant. In particular, studies have implicated vitamin E acetate as a potential instigator of EVALI. Pulmonary surfactant is vital to proper respiration through the mechanical processes of adsorption and interface stability to achieve and maintain low surface tension at the air-liquid interface. Using neutron spin echo spectroscopy, we investigate the impact of vitamin E acetate on the mechanical properties of two lipid-only pulmonary surfactant …


Detecting Mercury (Ii) And Thiocyanate Using “Turn-On” Fluorescence Of Graphene Quantum Dots, Faezeh Askari, Abbas Rahdar, Mohadeseh Dashti, John F. Trant Sep 2020

Detecting Mercury (Ii) And Thiocyanate Using “Turn-On” Fluorescence Of Graphene Quantum Dots, Faezeh Askari, Abbas Rahdar, Mohadeseh Dashti, John F. Trant

Chemistry and Biochemistry Publications

In this work, 1.8 nm graphene quantum dots (GQDs), exhibiting bright blue fluorescence, were prepared using a bottom-up synthesis from citric acid. The fluorescence of the GQDs could be almost completely quenched (about 96%) by adding Hg2+. Quenching was far less efficient with other similar heavy metals, Tl+, Pb2+ and Bi3+. Fluorescence could be near quantitatively restored through the introduction of thiocyanate. This “turn-on” fluorescence can thus be used to detect both or either environmental and physiological contaminants mercury and thiocyanate and could prove useful for the development of simple point-of-care diagnostics in the future. [Figure not available: see fulltext.].


The Synthesis Of Methotrexate-Loaded F127 Microemulsions And Their In Vivo Toxicity In A Rat Model, Abbas Rahdar, Mohammad Reza Hajinezhad, Sarah Nasri, Hamid Beyzaei, Mahmood Barani, John F. Trant Sep 2020

The Synthesis Of Methotrexate-Loaded F127 Microemulsions And Their In Vivo Toxicity In A Rat Model, Abbas Rahdar, Mohammad Reza Hajinezhad, Sarah Nasri, Hamid Beyzaei, Mahmood Barani, John F. Trant

Chemistry and Biochemistry Publications

Methotrexate (MTX) has been often formulated as nano and micro-emulsions, nominally to address its poor solubility and off-target effects. Nanoformulated MTX is universally reported to be a more efficacious anti-cancer agent than direct-dissolved drug; however, these investigations generally fail to screen for in vivo toxicity. This study aims to remedy this oversight. MTX was formulated as a standard Pluronic oil-in-water microemulsion with good drug encapsulation efficiency (73.0% ± 8.4). Preliminary in vitro free radical scavenging studies found that formulation reduces drug oxidation four-fold. The toxic effects of formulated and unformulated MTX were investigated in a Wistar rat model. Rats received …


Cannabinoids And Cannabinoid Receptors: The Story So Far, Fred Shahbazi, Victoria Grandi, Abhinandan Banerjee, John F. Trant Jul 2020

Cannabinoids And Cannabinoid Receptors: The Story So Far, Fred Shahbazi, Victoria Grandi, Abhinandan Banerjee, John F. Trant

Chemistry and Biochemistry Publications

Like most modern molecular biology and natural product chemistry, understanding cannabinoid pharmacology centers around molecular interactions, in this case, between the cannabinoids and their putative targets, the G-protein coupled receptors (GPCRs) cannabinoid receptor 1 (CB1) and cannabinoid receptor 2 (CB2). Understanding the complex structure and interplay between the partners in this molecular dance is required to understand the mechanism of action of synthetic, endogenous, and phytochemical cannabinoids. This review, with 91 references, surveys our understanding of the structural biology of the cannabinoids and their target receptors including both a critical comparison of the extant crystal structures and the computationally derived …


The Structures Of Polyunsaturated Lipid Bilayers By Joint Refinement Of Neutron And X-Ray Scattering Data, Drew Marquardt, Frederick A. Heberle, Jianjun Pan, Xiaolin Cheng, Georg Pabst, Thad A. Harroun, Norbert Kučerka, John Katsaras Jul 2020

The Structures Of Polyunsaturated Lipid Bilayers By Joint Refinement Of Neutron And X-Ray Scattering Data, Drew Marquardt, Frederick A. Heberle, Jianjun Pan, Xiaolin Cheng, Georg Pabst, Thad A. Harroun, Norbert Kučerka, John Katsaras

Chemistry and Biochemistry Publications

© 2020 Elsevier B.V. We present the detailed structural analysis of polyunsaturated fatty acid-containing phospholipids namely, 1-palmitoyl-2-docosahexaenoyl-sn-glycero-3-phosphocholine (PDPC) and 1-stearoyl-2-docosahexaenoyl-sn-glycero-3-phosphocholine (SDPC). A newly developed molecular dynamics (MD) simulation parsing scheme for lipids containing fatty acids with multiple double bonds was implemented into the scattering density profile (SDP) model to simultaneously refine differently contrasted neutron and X-ray scattering data. SDP analyses of scattering data at 30 °C yielded lipid areas of 71.1 Å2 and 70.4 Å2 for PDPC and SDPC bilayers, respectively, and a model free analysis of PDPC at 30 °C resulted in a lipid area of 72 Å2. In …


Differential Expression Of Glucose Transporters And Hexokinases In Prostate Cancer With A Neuroendocrine Gene Signature: A Mechanistic Perspective For 18 F-Fdg Imaging Of Psma-Suppressed Tumors, Martin K. Bakht, Jessica M. Lovnicki, Janice Tubman, Keith F. Stringer, Jonathan Chiaramonte, Michael R. Reynolds, Iulian Derecichei, Rosa Maria Ferraiuolo, Bre Anne Fifield, Dorota Lubanska, So Won Oh, Gi Jeong Cheon, Cheol Kwak, Chang Wook Jeong, Keon Wook Kang, John F. Trant, Colm Morrissey, Ilsa M. Coleman, Yuzhuo Wang, Hojjat Ahmadzadehfar Jun 2020

Differential Expression Of Glucose Transporters And Hexokinases In Prostate Cancer With A Neuroendocrine Gene Signature: A Mechanistic Perspective For 18 F-Fdg Imaging Of Psma-Suppressed Tumors, Martin K. Bakht, Jessica M. Lovnicki, Janice Tubman, Keith F. Stringer, Jonathan Chiaramonte, Michael R. Reynolds, Iulian Derecichei, Rosa Maria Ferraiuolo, Bre Anne Fifield, Dorota Lubanska, So Won Oh, Gi Jeong Cheon, Cheol Kwak, Chang Wook Jeong, Keon Wook Kang, John F. Trant, Colm Morrissey, Ilsa M. Coleman, Yuzhuo Wang, Hojjat Ahmadzadehfar

Chemistry and Biochemistry Publications

Although the incidence of de novo neuroendocrine prostate cancer (PC) is rare, recent data suggest that low expression of prostatespecific membrane antigen (PSMA) is associated with a spectrum of neuroendocrine hallmarks and androgen receptor (AR) suppression in PC. Previous clinical reports indicate that PCs with a phenotype similar to neuroendocrine tumors can be more amenable to imaging by 18F-FDG than by PSMA-targeting radioligands. In this study, we evaluated the association between neuroendocrine gene signature and 18F-FDG uptake-associated genes including glucose transporters (GLUTs) and hexokinases, with the goal of providing a genomic signature to explain the reported 18F-FDG avidity of PSMA …


Stretchable Ultrasheer Fabrics As Semitransparent Electrodes For Wearable Light-Emitting E-Textiles With Changeable Display Patterns, Yunyun Wu, Sara S. Mechael, Cecilia Lerma, R. Stephen Carmichael, Tricia Breen Carmichael Apr 2020

Stretchable Ultrasheer Fabrics As Semitransparent Electrodes For Wearable Light-Emitting E-Textiles With Changeable Display Patterns, Yunyun Wu, Sara S. Mechael, Cecilia Lerma, R. Stephen Carmichael, Tricia Breen Carmichael

Chemistry and Biochemistry Publications

Despite the development throughout human history of a wealth of textile materials and structures, the porous structures and non-planar surfaces of textiles are often viewed as problematic for the fabrication of wearable e-textiles and smart clothing. Here, we demonstrate a new textile-centric design paradigm in which we use the textile structure as an integral part of wearable device design. We coat the open framework structure of an ultrasheer knitted textile with a conformal gold film using solution-based metallization to form gold-coated ultrasheer electrodes that are highly conductive (3.6 ± 0.9 Ω/sq) and retain conductivity to 200% strain with R/R0 < 2. The ultrasheer electrodes produce wearable, highly stretchable light-emitting e-textiles that function to 200% strain. Stencil printing a wax resist provides patterned electrodes for patterned light emission; furthermore, incorporating soft-contact lamination produces light-emitting textiles that exhibit, for the first time, readily changeable patterns of illumination.


A Theoretical First Principles Computational Investigation Into The Potential Of Aluminum-Doped Boron Nitride Nanotubes For Hydrogen Storage, Mehdi Noura, Abbas Rahdar, S. Maryamdokht Taimoory, John J. Hayward, S. Iraj Sadraei, John F. Trant Mar 2020

A Theoretical First Principles Computational Investigation Into The Potential Of Aluminum-Doped Boron Nitride Nanotubes For Hydrogen Storage, Mehdi Noura, Abbas Rahdar, S. Maryamdokht Taimoory, John J. Hayward, S. Iraj Sadraei, John F. Trant

Chemistry and Biochemistry Publications

Hydrogen storage remains a largely unsolved problem facing the green energy revolution. One approach is physisorption on very high surface area materials incorporating metal atoms. Boron nitride nanotubes (BNNTs) are a promising material for this application as their behaviour is largely independent of the nanoscopic physical features providing a greater degree of tolerance in their synthesis. Aluminum doping has been shown to be a promising approach for carbon nanotubes but has been underexplored for BNNTs. Using first principles density functional theory, the energetics, electronics and structural impacts of aluminum adsorption to both zigzag and armchair polymorphs of BNNTs was investigated …


Transverse Lipid Organization Dictates Bending Fluctuations In Model Plasma Membranes, Brett W. Rickeard, Michael H.L. Nguyen, Mitchell Dipasquale, Caesar G. Yip, Hamilton Baker, Frederick A. Heberle, Xiaobing Zuo, Elizabeth G. Kelley, Michihiro Nagao, Drew Marquardt Jan 2020

Transverse Lipid Organization Dictates Bending Fluctuations In Model Plasma Membranes, Brett W. Rickeard, Michael H.L. Nguyen, Mitchell Dipasquale, Caesar G. Yip, Hamilton Baker, Frederick A. Heberle, Xiaobing Zuo, Elizabeth G. Kelley, Michihiro Nagao, Drew Marquardt

Chemistry and Biochemistry Publications

© 2020 The Royal Society of Chemistry. Membrane undulations play a vital role in many biological processes, including the regulation of membrane protein activity. The asymmetric lipid composition of most biological membranes complicates theoretical description of these bending fluctuations, yet experimental data that would inform any such a theory is scarce. Here, we used neutron spin-echo (NSE) spectroscopy to measure the bending fluctuations of large unilamellar vesicles (LUV) having an asymmetric transbilayer distribution of high- and low-melting lipids. The asymmetric vesicles were prepared using cyclodextrin-mediated lipid exchange, and were composed of an outer leaflet enriched in egg sphingomyelin (ESM) and …


The Antioxidant Vitamin E As A Membrane Raft Modulator: Tocopherols Do Not Abolish Lipid Domains, Mitchell Dipasquale, Michael H.L. Nguyen, Brett W. Rickeard, Nicole Cesca, Christopher Tannous, Stuart R. Castillo, John Katsaras, Elizabeth G. Kelley, Frederick A. Heberle, Drew Marquardt Jan 2020

The Antioxidant Vitamin E As A Membrane Raft Modulator: Tocopherols Do Not Abolish Lipid Domains, Mitchell Dipasquale, Michael H.L. Nguyen, Brett W. Rickeard, Nicole Cesca, Christopher Tannous, Stuart R. Castillo, John Katsaras, Elizabeth G. Kelley, Frederick A. Heberle, Drew Marquardt

Chemistry and Biochemistry Publications

© 2020 Elsevier B.V. The antioxidant vitamin E is a commonly used vitamin supplement. Although the multi-billion dollar vitamin and nutritional supplement industry encourages the use of vitamin E, there is very little evidence supporting its actual health benefits. Moreover, vitamin E is now marketed as a lipid raft destabilizing anti-cancer agent, in addition to its antioxidant behaviour. Here, we studied the influence of vitamin E and some of its vitamers on membrane raft stability using phase separating unilamellar lipid vesicles in conjunction with small-angle scattering techniques and fluorescence microscopy. We find that lipid phase behaviour remains unperturbed well beyond …


A Review And Critique Of Academic Lab Safety Research, A. Dana Ménard, John F. Trant Jan 2020

A Review And Critique Of Academic Lab Safety Research, A. Dana Ménard, John F. Trant

Chemistry and Biochemistry Publications

Over the past ten years, there have been several high-profile accidents in academic laboratories around the world, resulting in significant injuries and fatalities. The aftermath of these incidents is often characterized by calls for reflection and re-examination of the academic discipline’s approach to safety research and policy. However, the study of academic lab safety is still underdeveloped and necessary data about changes in safety attitudes and behaviours has not been gathered. This Review article critically examines the state of academic chemical safety research from a multifactorial stance, including research on the occurrence of lab accidents, contributors to lab accidents, the …


Photophysical And Optical Properties Of Semiconducting Polymer Nanoparticles Prepared From Hyaluronic Acid And Polysorbate 80, Adam Langlois, Gage T. Mason, Michael H.L. Nguyen, Mehdi Rezapour, Paul Ludovic Karsenti, Drew Marquardt, Simon Rondeau-Gagné Dec 2019

Photophysical And Optical Properties Of Semiconducting Polymer Nanoparticles Prepared From Hyaluronic Acid And Polysorbate 80, Adam Langlois, Gage T. Mason, Michael H.L. Nguyen, Mehdi Rezapour, Paul Ludovic Karsenti, Drew Marquardt, Simon Rondeau-Gagné

Chemistry and Biochemistry Publications

Copyright © 2019 American Chemical Society. A nanoprecipitation procedure was utilized to prepare novel diketopyrrolopyrrole-based semiconducting polymer nanoparticles (SPNs) with hyaluronic acid (HA) and polysorbate 80. The nanoprecipitation led to the formation of spherical nanoparticles with average diameters ranging from 100 to 200 nm, and a careful control over the structure of the parent conjugated polymers was performed to probe the influence of π-conjugation on the final photophysical and thermal stability of the resulting SPNs. Upon generation of a series of novel SPNs, the optical and photophysical properties of the new nanomaterials were probed in solution using various techniques including …


Covalently Functionalized Sawdust For The Remediation Of Phosphate From Agricultural Wastewater, Daniel Meister, David Ure, Angela Awada, Jean-Claude Barrette, Joel Gagnon, Bluent Mutus, John F. Trant Nov 2019

Covalently Functionalized Sawdust For The Remediation Of Phosphate From Agricultural Wastewater, Daniel Meister, David Ure, Angela Awada, Jean-Claude Barrette, Joel Gagnon, Bluent Mutus, John F. Trant

Chemistry and Biochemistry Publications

Phosphate remediation from wastewater is rapidly becoming an ever more attractive process due to a combination of both the economic pressure of increasing phosphate scarcity and the environmental damage caused by untreated agricultural runoff. Ideally, remediated phosphate will be recoverable and would be able to be reused as fertilizer. Many different resins have been investigated, but due to the scale of the challenge, any feasible solution will involve the use of very inexpensive waste products as the solid support. Sawdust, functionalized with iron-binding ligands, is such a potential resin. Sawdust alone binds 0.3 g/kg of phosphate which is insufficient. Iron …