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https://www.readbyqxmd.com/read/29036718/glutamatergic-response-to-heat-pain-stress-in-schizophrenia
#1
Joshua Chiappelli, Qiaoyun Shi, Sarah Andrea Wijtenburg, Raimi Quiton, Krista Wisner, Frank Gaston, Priyadurga Kodi, Christopher Gaudiot, Peter Kochunov, Laura M Rowland, Liyi Elliot Hong
Regulation of stress response involves top-down mechanisms of the frontal-limbic glutamatergic system. As schizophrenia is associated with glutamatergic abnormalities, we hypothesized that schizophrenia patients may have abnormal glutamatergic reactivity within the dorsal anterior cingulate cortex (dACC), a key region involved in perception of and reaction to stress. To test this, we developed a somatic stress paradigm involving pseudorandom application of safe but painfully hot stimuli to the forearm of participants while they were undergoing serial proton magnetic resonance spectroscopy to measure changes in glutamate and glutamine levels in the dACC...
September 23, 2017: Schizophrenia Bulletin
https://www.readbyqxmd.com/read/29036696/radiation-protection-measurements-with-the-variance-covariance-method-in-the-stray-radiation-fields-from-photon-and-proton-therapy-facilities
#2
J Lillhök, L Persson, C E Andersen, A Dasu, O Ardenfors
The microdosimetric variance-covariance method was used to study the stray radiation fields from the photon therapy facility at the Technical University of Denmark and the scanned proton therapy beam at the Skandion Clinic in Uppsala, Sweden. Two TEPCs were used to determine the absorbed dose, the dose-average lineal energy, the dose-average quality factor and the dose equivalent. The neutron component measured by the detectors at the proton beam was studied through Monte Carlo simulations using the code MCNP6...
September 29, 2017: Radiation Protection Dosimetry
https://www.readbyqxmd.com/read/29036685/nuclear-heating-in-lif-dosemeters-in-a-fusion-neutron-field-trial-of-direct-comparison-of-experimental-and-simulated-results
#3
Wladyslaw Pohorecki, Barbara Obryk
The results of nuclear heating measured by means of thermoluminescent dosemeters (TLD-LiF) in a Cu block irradiated by 14 MeV neutrons are presented. The integral Cu experiment relevant for verification of copper nuclear data at neutron energies characteristic for fusion facilities was performed in the ENEA FNG Laboratory at Frascati. Five types of TLDs were used: highly photon sensitive LiF:Mg,Cu,P (MCP-N), 7LiF:Mg,Cu,P (MCP-7) and standard, lower sensitivity LiF:Mg,Ti (MTS-N), 7LiF:Mg,Ti (MTS-7) and 6LiF:Mg,Ti (MTS-6)...
September 29, 2017: Radiation Protection Dosimetry
https://www.readbyqxmd.com/read/29036607/endoscopic-and-histopathologic-reflux-associated-mucosal-damage-in-the-remnant-esophagus-following-transthoracic-esophagectomy-for-cancer-5-year-long-term-follow-up
#4
H F Fuchs, H M Schmidt, M Meissner, S Brinkmann, M Maus, M Bludau, W Schröder, A H Hölscher, J M Leers
Gastroesophageal reflux is a common problem following esophagectomy and reconstruction with gastric interposition. Despite a routine prescription of proton pump inhibitors, reflux-associated mucosal damage in the remnant esophagus is frequently observed. Purpose of this study is to evaluate mucosal damage in the esophageal remnant during long-term follow-up and to compare the prevalence of this damage between the subgroups of esophageal squamous cell and adenocarcinoma. All patients undergoing transthoracic Ivor-Lewis esophagectomy were prospectively entered in our IRB approved database...
September 21, 2017: Diseases of the Esophagus: Official Journal of the International Society for Diseases of the Esophagus
https://www.readbyqxmd.com/read/29036585/ambulatory-ph-impedance-pressure-monitoring-as-a-diagnostic-tool-for-the-reflux-cough-syndrome
#5
T V K Herregods, A Pauwels, J Jafari, D Sifrim, A J P M Smout, A J Bredenoord, J Tack
Gastroesophageal reflux is considered to be a significant contributing factor to chronic unexplained cough. Patients are often presumed to have reflux-induced cough and are exposed to high-dose and long-term empirical therapy with proton pump inhibitors (PPIs) despite the limited treatment efficacy in this population. We aimed to assess the diagnostic value of 24-hour ambulatory pH-impedance-pressure monitoring for the diagnosis of reflux-induced chronic cough. In this multicenter study, we evaluated 192 patients with chronic cough using 24-hour pH-impedance-pressure monitoring off PPIs...
September 27, 2017: Diseases of the Esophagus: Official Journal of the International Society for Diseases of the Esophagus
https://www.readbyqxmd.com/read/29036565/long-term-risk-of-acute-myocardial-infarction-stroke-and-death-with-outpatient-use-of-clarithromycin-a-retrospective-cohort-study
#6
Andrew D Mosholder, Joo-Yeon Lee, Esther H Zhou, Elizabeth M Kang, Mayurika Ghosh, Rima Izem, Jacqueline M Major, David J Graham
This retrospective cohort study of subjects enrolled in the United Kingdom Clinical Practice Research Datalink from 2000-2013 evaluated long-term risks of death, stroke, and acute myocardial infarction (AMI) in adults prescribed clarithromycin. Subjects were outpatients aged 40-85 years prescribed clarithromycin, doxycycline, or erythromycin (287,748, 267,729, and 442,999 patients, respectively), or H. pylori eradication therapy with a proton pump inhibitor, amoxicillin, and either clarithromycin (27,639 patients) or metronidazole (14,863 patients)...
September 20, 2017: American Journal of Epidemiology
https://www.readbyqxmd.com/read/29036364/nanodosimetry-towards-a-new-concept-of-radiation-quality
#7
V Conte, A Selva, P Colautti, G Hilgers, H Rabus, A Bantsar, M Pietrzak, S Pszona
The biological action of ionizing charged particles is initiated at the DNA level, and the effectiveness with which the initial physical effect changes into measurable biological damage is likely ruled by the stochastics of ionizations produced by the incident ions in subcellular nanometric volumes. Based on this hypothesis, experimental nanodosimetry aims at establishing a new concept of radiation quality that builds on measurable characteristics of the particle track structure at the nanometer scale. Three different nanodosimetric detection systems have been developed to date that allow measurements of the number of ionizations produced by the passage of a primary particle in a nanometer-size gas volume (in unit density scale)...
September 23, 2017: Radiation Protection Dosimetry
https://www.readbyqxmd.com/read/29035543/speciated-monitoring-of-gas-phase-organic-peroxy-radicals-by-chemical-ionization-mass-spectrometry-cross-reactions-between-ch3o2-ch3-co-o2-ch3-3co2-and-c-c6h11o2
#8
Barbara Noziere, David R Hanson
Organic peroxy radicals ("RO2", with R organic) are key intermediates in most oxygen-rich systems where organic compounds are oxidized (natural environment, flames, combustion engines, living organisms…). But, until recently, techniques able to monitor simultaneously and distinguish between RO2 species ("speciated" detection) have been scarce, which has limited the understanding of complex systems containing these radicals. Mass Spectrometry using proton transfer ionization has been shown previously to detect individual gas-phase RO2 separately...
October 16, 2017: Journal of Physical Chemistry. A
https://www.readbyqxmd.com/read/29035522/cobalt-ion-promoted-redox-cascade-a-route-to-spiro-oxazine-oxazepine-derivatives-and-a-dinuclear-cobalt-iii-complex-of-an-n-1-4-naphthoquinone-o-aminophenol-derivative
#9
Sandip Mondal, Sachinath Bera, Suvendu Maity, Prasanta Ghosh
The study discloses that the redox activity of N-(1,4-naphthoquinone)-o-aminophenol derivatives (L(R)H2) containing a (phenol)-NH-(1,4-naphthoquinone) fragment is notably different from that of a (phenol)-NH-(phenol) precursor. The former is a platform for a redox cascade. L(R)H2 is redox noninnocent and exists in Cat-N-(1,4-naphthoquinone)(2-) (L(R 2-)) and SQ-N-(1,4-naphthoquinone) (L(R •-)) states in the complexes. Reactions of L(R)H2 with cobalt(II) salts in MeOH in air promote a cascade affording spiro oxazine-oxazepine derivatives ((OX)L(R)) in good yields, when R = H, Me, (t)Bu...
October 16, 2017: Inorganic Chemistry
https://www.readbyqxmd.com/read/29035503/comparison-between-short-and-long-echo-time-magnetic-resonance-spectroscopic-imaging-at-3t-and-7t-for-evaluating-brain-metabolites-in-patients-with-glioma
#10
Yan Li, Marisa Lafontaine, Susan Chang, Sarah J Nelson
Three-dimensional proton magnetic resonance spectroscopic imaging (MRSI) is a powerful non-invasive tool for characterizing spatial variations in metabolic profiles for patients with glioma. Metabolic parameters obtained using this technique have been shown to predict treatment response, disease progression, and transformation to a more malignant phenotype. The availability of ultra-high-field MR systems has the potential to improve the characterization of metabolites. The purpose of this study was to compare the metabolite profiles acquired with conventional long echo time (TE) MRSI at 3T with those obtained with short TE MRSI at 3T and 7T in patients with glioma...
October 16, 2017: ACS Chemical Neuroscience
https://www.readbyqxmd.com/read/29035049/exceptionally-high-proton-and-lithium-cation-gas-phase-basicity-of-the-anti-diabetic-drug-metformin
#11
Ewa Daniela Raczynska, Jean-Francois Gal, Pierre-Charles Maria, Piotr Michalec, Marcin Zalewski
Substituted biguanides are known for their biological effect and a few of them are used as drugs, the most prominent example being metformin (1,1-dimethylbiguanide, IUPAC name: N,N-dimethylimidodicarbonimidic diamide). Owing to the presence of hydrogen atoms at the amino groups, biguanides exhibit a multiple tautomerism. This aspect of their structures was examined in detail for unsubstituted biguanide and metformin in the gas phase. At the DFT level {essentially B3LYP/6-311+G(d,p)}, the most stable structures correspond to the conjugated, push-pull, system (NR2)(NH2)C=N-C(=NH)NH2 (R= H, CH3), further stabilized by an internal hydrogen bond...
October 16, 2017: Journal of Physical Chemistry. A
https://www.readbyqxmd.com/read/29035047/electrocatalytic-water-oxidation-by-a-water-soluble-copper-ii-complex-with-a-copper-bound-carbonate-group-acting-as-a-potential-proton-shuttle
#12
Fangfang Chen, Ni Wang, Haitao Lei, Dingyi Guo, Hongfei Liu, Zongyao Zhang, Wei Zhang, Wenzhen Lai, Rui Cao
Water-soluble copper(II) complexes of the dianionic tridentate pincer ligand N,N'-2,6-dimethylphenyl-2,6-pyridinedicarboxamidate (L) are catalysts for water oxidation. In [L-Cu(II)-DMF] (1, DMF = dimethylformamide) and [L-Cu(II)-OAc](-) (2, OAc = acetate), ligand L binds Cu(II) through three N atoms, which define an equatorial plane. The fourth coordination site of the equatorial plane is occupied by DMF in 1 and by OAc(-) in 2. These two complexes can electrocatalyze water oxidation to evolve O2 in 0.1 M pH 10 carbonate buffer...
October 16, 2017: Inorganic Chemistry
https://www.readbyqxmd.com/read/29034950/spectroscopic-characteristics-of-rubricoccus-marinus-xenorhodopsin-rmxer-and-a-putative-model-for-its-inward-h-transport-mechanism
#13
Saki Inoue, Susumu Yoshizawa, Yu Nakajima, Keiichi Kojima, Takashi Tsukamoto, Takashi Kikukawa, Yuki Sudo
A new group of microbial rhodopsins named xenorhodopsins (XeR), which are closely related to the cyanobacterial Anabaena sensory rhodopsin, show a light-driven "inward" proton transport activity, as reported for one representative of this group from Parvularcula oceani (PoXeR). In this study, we functionally and spectroscopically characterized a new member of the XeR clade from a marine bacterium Rubricoccus marinus SG-29(T) (RmXeR). Escherichia coli cells expressing recombinant RmXeR showed a light-induced alkalization of the cell suspension, which was strongly impaired by a protonophore, suggesting that RmXeR is a light-driven "inward" proton pump as is PoXeR...
October 16, 2017: Physical Chemistry Chemical Physics: PCCP
https://www.readbyqxmd.com/read/29034914/local-water-sensing-water-exchange-in-bacterial-photosynthetic-reaction-centers-embedded-in-a-trehalose-glass-studied-using-multiresonance-epr
#14
Anna Nalepa, Marco Malferrari, Wolfgang Lubitz, Giovanni Venturoli, Klaus Möbius, Anton Savitsky
Using isotope labeled water (D2O and H2(17)O) and pulsed W-band (94 GHz) high-field multiresonance EPR spectroscopies, such as ELDOR-detected NMR and ENDOR, the biologically important question of detection and quantification of local water in proteins is addressed. A bacterial reaction center (bRC) from Rhodobacter sphaeroides R26 embedded into a trehalose glass matrix is used as a model system. The bRC hosts the two native radical cofactor ions (primary electron donor) and (primary electron acceptor) as well as an artificial nitroxide spin label site-specifically attached to the surface of the H-protein domain...
October 16, 2017: Physical Chemistry Chemical Physics: PCCP
https://www.readbyqxmd.com/read/29034913/a-proton-hopping-charge-storage-mechanism-of-ionic-one-dimensional-coordination-polymers-for-high-performance-supercapacitors
#15
Nutthaphon Phattharasupakun, Juthaporn Wutthiprom, Surasak Kaenket, Thana Maihom, Jumras Limtrakul, Michael Probst, Sanjog S Nagarkar, Satoshi Horike, Montree Sawangphruk
A proton-conducting coordination polymer of anionic one-dimensional (1D) chains of Zn(2+) phosphate and protonated imidazole with the formula of [Zn(HPO4)(H2PO4)2](ImH2)2 has been used as a novel supercapacitor material in aqueous electrolytes. This material stores charges via a proton-hopping mechanism.
October 16, 2017: Chemical Communications: Chem Comm
https://www.readbyqxmd.com/read/29034790/minimal-toxicity-after-proton-beam-therapy-for-prostate-and-pelvic-nodal-irradiation-results-from-the-proton-collaborative-group-reg001-09-trial
#16
Michael D Chuong, William Hartsell, Gary Larson, Henry Tsai, George E Laramore, Carl J Rossi, J Ben Wilkinson, Adeel Kaiser, Carlos Vargas
BACKGROUND: Proton beam therapy (PBT) reduces normal organ dose compared to intensity modulated radiation therapy (IMXT) for prostate cancer patients who receive pelvic radiation therapy. It is not known whether this dosimetric advantage results in less gastrointestinal (GI) and genitourinary (GU) toxicity than would be expected from IMXT. MATERIAL AND METHODS: We evaluated treatment parameters and toxicity outcomes for non-metastatic prostate cancer patients who received pelvic radiation therapy and enrolled on the PCG REG001-09 trial...
October 14, 2017: Acta Oncologica
https://www.readbyqxmd.com/read/29034505/in-vivo-characterization-of-the-downfield-part-of-1-h-mr-spectra-of-human-brain-at-9-4-t-magnetization-exchange-with-water-and-relation-to-conventionally-determined-metabolite-content
#17
Nicole D Fichtner, Ioannis-Angelos Giapitzakis, Nikolai Avdievich, Ralf Mekle, Daniel Zaldivar, Anke Henning, Roland Kreis
PURPOSE: To perform exchange-rate measurements on the in vivo human brain downfield spectrum (5-10 ppm) at 9.4 T and to compare the variation in concentrations of the downfield resonances and of known upfield metabolites to determine potential peak labels. METHODS: Non-water-suppressed metabolite cycling was used in combination with an inversion transfer technique in two brain locations in healthy volunteers to measure the exchange rates and T1 values of exchanging peaks...
October 16, 2017: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
https://www.readbyqxmd.com/read/29034122/methanol-on-anatase-tio2-101-mechanistic-insights-into-photocatalysis
#18
Martin Setvin, Xiao Shi, Jan Hulva, Thomas Simschitz, Gareth S Parkinson, Michael Schmid, Cristiana Di Valentin, Annabella Selloni, Ulrike Diebold
The photoactivity of methanol adsorbed on the anatase TiO2 (101) surface was studied by a combination of scanning tunneling microscopy (STM), temperature-programmed desorption (TPD), X-ray photoemission spectroscopy (XPS), and density functional theory (DFT) calculations. Isolated methanol molecules adsorbed at the anatase (101) surface show a negligible photoactivity. Two ways of methanol activation were found. First, methoxy groups formed by reaction of methanol with coadsorbed O2 molecules or terminal OH groups are photoactive, and they turn into formaldehyde upon UV illumination...
October 6, 2017: ACS Catalysis
https://www.readbyqxmd.com/read/29034088/emerging-dilemmas-in-the-diagnosis-and-management-of-gastroesophageal-reflux-disease
#19
REVIEW
Peter Kahrilas, Rena Yadlapati, Sabine Roman
Gastroesophageal reflux disease (GERD) is common, but less so than widely reported because of inconsistencies in definition. In clinical practice, the diagnosis is usually based on a symptom assessment without testing, and the extent of diagnostic testing pursued should be limited to that which guides management or which protects the patient from the risks of a potentially morbid treatment or an undetected early (or imminent) esophageal adenocarcinoma or which does both. When testing is pursued, upper gastrointestinal endoscopy is the most useful initial diagnostic test because it evaluates for the major potential morbidities (Barrett's, stricture, and cancer) associated with GERD and facilitates the identification of some alternative diagnostic possibilities such as eosinophilic esophagitis...
2017: F1000Research
https://www.readbyqxmd.com/read/29033900/weak-organic-acids-decrease-borrelia-burgdorferi-cytoplasmic-ph-eliciting-an-acid-stress-response-and-impacting-rpon-and-rpos-dependent-gene-expression
#20
Daniel P Dulebohn, Crystal L Richards, Hua Su, Kevin A Lawrence, Frank C Gherardini
The spirochete Borrelia burgdorferi survives in its tick vector, Ixodes scapularis, or within various hosts. To transition between and survive in these distinct niches, B. burgdorferi changes its gene expression in response to environmental cues, both biochemical and physiological. Exposure of B. burgdorferi to weak monocarboxylic organic acids, including those detected in the blood meal of fed ticks, decreased the cytoplasmic pH of B. burgdorferi in vitro. A decrease in the cytoplasmic pH induced the expression of genes encoding enzymes that have been shown to restore pH homeostasis in other bacteria...
2017: Frontiers in Microbiology
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