Physical Sciences and Mathematics Commons^™

Nicotine Exploits A Copi-Mediated Process For Chaperone-Mediated Up-Regulation Of Its Receptors, Brandon J. Henderson, Rahul Srinivasan, Weston A. Nichols, Crystal N. Dilworth, Diana F. Gutierrez, Elisha D. W. Mackey, Sheri Mckinney, Ryan M. Drenan, Christopher I. Richards, Henry A. Lester

Chemistry Faculty Publications

Chronic exposure to nicotine up-regulates high sensitivity nicotinic acetylcholine receptors (nAChRs) in the brain. This up-regulation partially underlies addiction and may also contribute to protection against Parkinson's disease. nAChRs containing the α6 subunit (α6* nAChRs) are expressed in neurons in several brain regions, but comparatively little is known about the effect of chronic nicotine on these nAChRs. We report here that nicotine up-regulates α6* nAChRs in several mouse brain regions (substantia nigra pars compacta, ventral tegmental area, medial habenula, and superior colliculus) and in neuroblastoma 2a cells. We present evidence that a coat protein complex I (COPI)-mediated process mediates this …

Conversion Of Iodide To Hypoiodous Acid And Iodine In Aqueous Microdroplets Exposed To Ozone, Elizabeth A. Pillar, Marcelo I. Guzman, Jose M. Rodriguez

Chemistry Faculty Publications

Halides are incorporated into aerosol sea spray, where they start the catalytic destruction of ozone (O₃) over the oceans and affect the global troposphere. Two intriguing environmental problems undergoing continuous research are (1) to understand how reactive gas phase molecular halogens are directly produced from inorganic halides exposed to O₃ and (2) to constrain the environmental factors that control this interfacial process. This paper presents a laboratory study of the reaction of O₃ at variable iodide (I^–) concentration (0.010–100 μM) for solutions aerosolized at 25 °C, which reveal remarkable differences in the reaction intermediates …

Thimerosal Exposure And The Role Of Sulfation Chemistry And Thiol Availability In Autism, Janet K. Kern, Boyd E. Haley, David A. Geier, Lisa K. Sykes, Paul G. King, Mark R. Geier

Chemistry Faculty Publications

Autism spectrum disorder (ASD) is a neurological disorder in which a significant number of the children experience a developmental regression characterized by a loss of previously acquired skills and abilities. Typically reported are losses of verbal, nonverbal, and social abilities. Several recent studies suggest that children diagnosed with an ASD have abnormal sulfation chemistry, limited thiol availability, and decreased glutathione (GSH) reserve capacity, resulting in a compromised oxidation/reduction (redox) and detoxification capacity. Research indicates that the availability of thiols, particularly GSH, can influence the effects of thimerosal (TM) and other mercury (Hg) compounds. TM is an organomercurial compound (49.55% Hg …

Amyloid Β-Peptide (1–42)-Induced Oxidative Stress In Alzheimer Disease: Importance In Disease Pathogenesis And Progression, D. Allan Butterfield, Aaron M. Swomley, Rukhsana Sultana

Chemistry Faculty Publications

Significance: Alzheimer disease (AD) is an age-related neurodegenerative disease. AD is characterized by progressive cognitive impairment. One of the main histopathological hallmarks of AD brain is the presence of senile plaques (SPs) and another is elevated oxidative stress. The main component of SPs is amyloid beta-peptide (Aβ) that is derived from the proteolytic cleavage of amyloid precursor protein.

Recent Advances: Recent studies are consistent with the notion that methionine present at 35 position of Aβ is critical to Aβ-induced oxidative stress and neurotoxicity. Further, we also discuss the signatures of oxidatively modified brain proteins, identified using redox proteomics approaches, during …

Single-Step Electrochemical Functionalization Of Double-Walled Carbon Nanotube (Dwcnt) Membranes And The Demonstration Of Ionic Rectification, Xin Zhan, Ji Wu, Zhiqiang Chen, Bruce J. Hinds

Chemistry Faculty Publications

Carbon nanotube (CNT) membranes allow the mimicking of natural ion channels for applications in drug delivery and chemical separation. Double-walled carbon nanotube membranes were simply functionalized with dye in a single step instead of the previous two-step functionalization. Non-faradic electrochemical impedance spectra indicated that the functionalized gatekeeper by single-step modification can be actuated to mimic the protein channel under bias. This functional chemistry was proven by a highly efficient ion rectification, wherein the highest experimental rectification factor of ferricyanide was up to 14.4. One-step functionalization by electrooxidation of amine provides a simple and promising functionalization chemistry for the application of …

2,2',5',6-Tetrachloro-4-[(1S)-1-Methylpropoxy]Biphenyl, Hans-Joachim Lehmler, Huimin Wu, Sean Parkin

Chemistry Faculty Publications

In the title molecule, C₁₆H₁₄Cl₄O, the dihedral angle between the least-square planes of the benzene rings is 84.40 (7)°. No unusual intermolecular interactions are present.

Topography-Guided Spreading And Drying Of 6,13-Bis(Triisopropylsilylethynyl)-Pentacene Solution On A Polymer Insulator For The Field-Effect Mobility Enhancement, Chang-Min Keum, Jin-Hyuk Bae, Min-Hoi Kim, Hea-Lim Park, Marcia M. Payne, John E. Anthony, Sin-Doo Lee

Chemistry Faculty Publications

We report on the enhancement of the field-effect mobility of solution-processed 6,13-bis(triisopropylsilylethynyl)-pentacene (TIPS-pentacene) by unidirectional topography (UT) of an inkjet-printed polymer insulator. The UT leads to anisotropic spreading and drying of the TIPS-pentacene droplet and enables to spontaneously develop the ordered structures during the solvent evaporation. The mobility of the UT-dictated TIPS-pentacene film (0.202 ± 0.012 cm²/Vs) is found to increase by more than a factor of two compared to that of the isotropic case (0.090 ± 0.032 cm²/Vs). The structural arrangement of the TIPS-pentacene molecules in relation to the mobility enhancement is described within an …

5,5'-Dichloro-2,2'-Dimethoxybiphenyl, Hans-Joachim Lehmler, Huimin Wu, Sean Parkin

Chemistry Faculty Publications

In the title molecule, C₁₄H₁₂Cl₂O₂, the dihedral angle between the least-square planes of the benzene rings is 62.17 (6)°. Both methoxy groups are slightly out of the plane of the benzene rings to which they are attached, making dihedral angles of 4.22 (18) and 18.82 (16)°.

3,4',5-Trichlorobiphenyl-4-Yl 2,2,2-Trichloroethyl Sulfate, Hans-Joachim Lehmler, Xianran He, Michael W. Duffel, Sean Parkin

Chemistry Faculty Publications

Crystals of the title compound, C₁₄H₈Cl₆O₄S, are twinned by inversion, with unequal components [0.85 (3):0.15 (3)]. The asymmetric unit contains two independent molecules that are related by a pseudo-inversion center. The C_ar-O [1.393 (9) and 1.397 (9) Å] and ester S-O bond lengths [1.600 (5) and 1.590 (5) Å] of both molecules are comparable to the structurally related 2,3,5,5-trichlorobiphenyl-4-yl 2,2,2-trichloroethyl sulfate. The dihedral angles between the benzene rings in the two molecules are 37.8 (2) and 35.0 (2)°.

Oxidative Modification Of Lipoic Acid By Hne In Alzheimer Disease Brain, Sarita S. Hardas, Rukhsana Sultana, Amy M. Clark, Tina L. Beckett, Luke I. Szweda, M. Paul Murphy, D. Allan Butterfield

Chemistry Faculty Publications

Alzheimer disease (AD) is an age-related neurodegenerative disease characterized by the presence of three pathological hallmarks: synapse loss, extracellular senile plaques (SP) and intracellular neurofibrillary tangles (NFTs). The major component of SP is amyloid β-peptide (Aβ), which has been shown to induce oxidative stress. The AD brain shows increased levels of lipid peroxidation products, including 4-hydroxy-2-nonenal (HNE). HNE can react covalently with Cys, His, or Lys residues on proteins, altering structure and function of the latter. In the present study we measured the levels of the HNE-modified lipoic acid in brain of subjects with AD and age-matched controls. Lipoic acid …