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https://www.readbyqxmd.com/read/28214778/thiol-disulfide-homeostasis-in-untreated-schizophrenia-patients
#1
Canan Topcuoglu, Abdurrahim Bakirhan, Fatma Meric Yilmaz, Salim Neselioglu, Ozcan Erel, Safak Yalcin Sahiner
BACKROUND: The aim of the study was to investigate dynamic thiol/disulfide (SH/SS) homeostasis in untreated schizophrenia. METHODS: Blood thiol/disulfide homeostasis status, which reflects native thiol-disulfide exchanges, was investigated in 87 untreated patients (52 males, 35 females), and the obtained results were compared with 86 healthy controls. Blood serum native thiol and total thiol (ToSH) concentrations were measured in a paired test. The half value of the difference between native thiol and ToSH concentrations was calculated as the disulfide bond amount...
February 7, 2017: Psychiatry Research
https://www.readbyqxmd.com/read/28214776/the-metabolic-impact-of-extracellular-nitrite-on-aerobic-metabolism-of-paracoccus-denitrificans
#2
K R Hartop, M J Sullivan, G Giannopoulos, A J Gates, P L Bond, Z Yuan, T A Clarke, G Rowley, D J Richardson
Nitrite, in equilibrium with free nitrous acid (FNA), can inhibit both aerobic and anaerobic growth of microbial communities through bactericidal activities that have considerable potential for control of microbial growth in a range of water systems. There has been much focus on the effect of nitrite/FNA on anaerobic metabolism and so, to enhance understanding of the metabolic impact of nitrite/FNA on aerobic metabolism, a study was undertaken with a model denitrifying bacterium Paracoccus denitrificans PD1222...
February 7, 2017: Water Research
https://www.readbyqxmd.com/read/28214718/alkyl-substituent-effect-on-photosensitized-inactivation-of-escherichia-coli-by-pyridinium-bonded-p-porphyrins
#3
Jin Matsumoto, Yusaku Suemoto, Hiroki Kanemaru, Kyosuke Takemori, Masato Shigehara, Akari Miyamoto, Haruhiko Yokoi, Masahide Yasuda
Activity of singlet oxygen sensitizers for photoinactivation of bacteria and photodynamic therapy of tumor cells has been evaluated using nonpathogenic model cells, such as Escherichia coli, Saccharomyces cerevisiae, and HeLa cells. Among them, E. coli, gram-negative bacterium, has complex membrane structures in the cell wall, resulting in an impermeable barrier to antimicrobial agents. Therefore, few singlet oxygen sensitizers have photoinactivation activities toward E. coli at low concentrations. Recently polycationic porphyrins have received much attention as a new type of singlet oxygen sensitizers because they have strong binding affinities for DNA and proteins...
February 6, 2017: Journal of Photochemistry and Photobiology. B, Biology
https://www.readbyqxmd.com/read/28214629/effects-of-metal-ion-replacement-on-pyrazinamidase-activity-a-quantum-mechanical-study
#4
Mahmoud Khadem-Maaref, Faramarz Mehrnejad, Arash Phirouznia
Pyrazinamidase (PZase), a metalloenzyme, is responsible for acidic modification of pyrazinamide (PZA), a drug used in tuberculosis treatment. The metal coordination site of the enzyme is able to coordinate various divalent metal cofactors. Previous experimental studies have demonstrated that metal ions, such as Co(2+), Mn(2+), and Zn(2+), are able to reactivate metal-depleted PZase, while others including Cu(2+), Fe(2+), and Mg(2+), cannot restore activity. In this study, we investigated binding of various metal ions to the metal coordination site (MCS) of the enzyme using quantum mechanical calculations...
February 2, 2017: Journal of Molecular Graphics & Modelling
https://www.readbyqxmd.com/read/28214513/molecular-dynamics-simulation-study-of-the-effect-of-glycerol-dialkyl-glycerol-tetraether-hydroxylation-on-membrane-thermostability
#5
Carme Huguet, Susanne Fietz, Antoni Rosell-Melé, Xavier Daura, Lionel Costenaro
Archaeal tetraether membrane lipids span the whole membrane width and present two C40 isoprenoid chains bound by two glycerol groups (or one glycerol and calditol). These lipids confer stability and maintain the membrane fluidity in mesophile to extremophile environments, making them very attractive for biotechnological applications. The isoprenoid lipid composition in archaeal membranes varies with temperature, which has placed these lipids in the focus of paleo-climatological studies for about a decade. Non-hydroxylated isoprenoid archaeal lipids are typically used as paleo-thermometry proxies, but recently identified hydroxylated (OH) derivatives have also been proposed as temperature proxies...
February 15, 2017: Biochimica et Biophysica Acta
https://www.readbyqxmd.com/read/28214511/identification-of-a-degradation-signal-sequence-within-substrates-of-the-mitochondrial-i-aaa-protease
#6
Anthony J Rampello, Steven E Glynn
The i-AAA protease is a component of the mitochondrial quality control machinery that regulates respiration, mitochondrial dynamics, and protein import. The protease is required to select specific substrates for degradation from among the diverse complement of proteins present in mitochondria, yet the rules that govern this selection are unclear. Here, we reconstruct the yeast i-AAA protease, Yme1p, to examine the in vitro degradation of two intermembrane space chaperone subunits, Tim9 and Tim10. Yme1p degrades Tim10 more rapidly than Tim9 despite high sequence and structural similarity, and loss of Tim10 is accelerated by disruption of conserved disulfide bonds within the substrate...
February 15, 2017: Journal of Molecular Biology
https://www.readbyqxmd.com/read/28214428/metal-metal-bond-excitation-in-colloidal-solution-of-nbs3
#7
Sofya B Artemkina, Ekaterina D Grayfer, Mariia N Kozlova, Svetlana G Kozlova, Maxim R Ryzhikov, Igor R Shein, Vladimir E Fedorov
For the first time the comparison of the theoretical and experimental data have shown that UV-vis absorption in the region of 600nm in colloidal solution of NbS3 can be described by the d-d electronic transitions to the antibonding molecular orbital. It is proved that the process leads to excitation of metal-metal bond.
February 5, 2017: Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
https://www.readbyqxmd.com/read/28214336/evidence-to-show-that-acetonitrile-is-sensitive-to-different-interactions-sites-of-ionic-liquids-as-unveiled-by-excess-spectroscopy
#8
Yu Zhou, Yan-Zhen Zheng, Tian Zhang, Geng Deng, Zhi-Wu Yu
By studying the interactions between an ionic liquid (IL), 1-ethyl-3-methylimidazolium bis (trifluoromethylsulfonyl) imide ([Emim][Tf2N]) and a co-solvent acetonitrile, C≡N stretching vibration was found to be very sensitive to different interaction sites as unveiled by excess infrared spectroscopy. Four existing forms of acetonitrile molecules were identified and the detailed transformation process of the ionic liquid upon dilution was obtained. Such characteristic of nitrile group is discussed from the view point of its ability to form hydrogen bonds with proton donors...
February 18, 2017: Chemphyschem: a European Journal of Chemical Physics and Physical Chemistry
https://www.readbyqxmd.com/read/28214230/synthesis-and-cytotoxic-activities-of-goniothalamins-and-derivatives
#9
Anja Weber, Katja Döhl, Julia Sachs, Anja C M Nordschild, Dennis Schröder, Andrea Kulik, Thomas Fischer, Lutz Schmitt, Nicole Teusch, Jörg Pietruszka
Substituted goniothalamins containing cyclopropane-groups were efficiently prepared in high yields and good selectivity. Antiproliferative activity was measured on three human cancer cell lines (A549, MCF-7, HBL-100), to show which of the structural elements of goniothalamins is mandatory for cytotoxicity. We found that the configuration of the stereogenic centre of the δ-lactone plays an important role for cytotoxicity. In our studies only (R)-configured goniothalamins showed antiproliferative activity, whereby (R)-configuration accords to natural goniothalamin (R)-1...
February 6, 2017: Bioorganic & Medicinal Chemistry
https://www.readbyqxmd.com/read/28213935/effect-of-a-one-step-self-etch-adhesive-on-endogenous-dentin-matrix-metalloproteinases
#10
Fabianni M Apolonio, Annalisa Mazzoni, Valeria Angeloni, Polliana M C Scaffa, Spartaco Santi, Vicente de Paulo A Saboia, Franklin R Tay, David H Pashley, Lorenzo Breschi
Degradation of the hybrid layer created in dentin by dentin adhesives is caused by enzyme activities present within the dentin matrix that destroy unprotected collagen fibrils. The aim of the present study was to evaluate the effect of a one-step self-etch adhesive system on dentinal matrix metalloproteinases 2 and 4 (MMP-2 and MMP-9, respectively) using in situ zymography and an enzymatic activity assay. The null hypothesis tested was that there are no differences in the activities of dentinal MMPs before and after treatment with a one-step adhesive system...
February 17, 2017: European Journal of Oral Sciences
https://www.readbyqxmd.com/read/28213894/controllable-rotating-behavior-of-individual-dielectric-micro-rod-in-a-rotating-electric-field
#11
Weiyu Liu, Yukun Ren, Ye Tao, Yanbo Li, Xiaoming Chen
We report herein controllable rotating behavior of an individual dielectric micro-rod driven by a background rotating electric field. By disposing or removing structured floating microelectrode, the rigid rod suspended in electrolyte solution accordingly exhibits co-field or anti-field rotating motion. In the absence of the ideally polarizable metal surface, the dielectric rod rotates opposite to propagation of electric field, with the measured rotating rate much larger than predicted by Maxwell-Wager interfacial polarization theory incorporating surface conduction of fixed bond charge...
February 18, 2017: Electrophoresis
https://www.readbyqxmd.com/read/28213824/an-approach-to-the-research-on-ion-and-water-properties-in-the-interphase-between-the-plasma-membrane-and-bulk-extracellular-solution
#12
REVIEW
Hiroshi Hibino, Madoka Takai, Hidenori Noguchi, Seishiro Sawamura, Yasufumi Takahashi, Hideki Sakai, Hitoshi Shiku
In vivo, cells are immersed in an extracellular solution that contains a variety of bioactive substances including ions and water. Classical electrophysiological analyses of epithelial cells in the stomach and small intestine have revealed that within a distance of several hundred micrometers above their apical plasma membrane, lies an extracellular layer that shows ion concentration gradients undetectable in the bulk phase. This "unstirred layer", which contains stagnant solutes, may also exist between the bulk extracellular solution and membranes of other cells in an organism and may show different properties...
February 17, 2017: Journal of Physiological Sciences: JPS
https://www.readbyqxmd.com/read/28213709/high-efficiency-removal-of-triclosan-by-structure-directing-agent-modified-mesoporous-mil-53-al
#13
Rongni Dou, Junya Zhang, Yuancai Chen, Siyuan Feng
In order to expand the potential applications of metal-organic frameworks (MOFs), structure directing agents modified mesoporous MIL-53(Al) (MIL-53(Al)-1) was investigated to adsorb triclosan (TCS) with two different initial concentrations. MIL-53(Al)-1 with high mesoporosity and total pore volume exhibited higher adsorption capacity and 4.4 times faster adsorption of TCS at low concentration (1 mg L(-1)) than that of microporous MIL-53(Al). Also, mesoporous as well as microporous MIL-53(Al) showed significant higher adsorption capacity and two orders of magnitude greater fast uptake of TCS than two kinds of mesoporous-activated carbon...
February 18, 2017: Environmental Science and Pollution Research International
https://www.readbyqxmd.com/read/28213673/individual-placement-and-support-ips-for-methadone-maintenance-therapy-patients-a-pilot-randomized-controlled-trial
#14
Carrie E Lones, Gary R Bond, Mark P McGovern, Kathryn Carr, Teresa Leckron-Myers, Tim Hartnett, Deborah R Becker
Individual Placement and Support (IPS) is an evidence-based employment model for people with severe mental illness, but it has not been evaluated for clients enrolled in substance abuse treatment programs. This study evaluated the effectiveness of IPS for people with opioid use disorders enrolled in an opioid treatment program. Within a randomized controlled experiment, 45 patients receiving methadone maintenance therapy were assigned to either IPS or a 6-month waitlist. The waitlist group received IPS after 6 months...
February 17, 2017: Administration and Policy in Mental Health
https://www.readbyqxmd.com/read/28213625/8-nitro-cgmp-a-novel-protein-reactive-cnmp-and-its-emerging-roles-in-autophagy
#15
Hirokazu Arimoto, Daiki Takahashi
Nitric oxide (NO) raises the intracellular 3',5'-cyclic guanosine monophosphate (cGMP) level through the activation of soluble guanylate cyclase and, in the presence of reactive oxygen species (ROS), reacts with biomolecules to produce nitrated cGMP derivatives. 8-Nitro-cGMP was the first endogenous cGMP derivative discovered in mammalian cells (2007) and was later found in plant cells. Among the six nitrogen atoms in this molecule, the one in the nitro group (NO2) comes from NO. This chapter asserts that this newly found cGMP is undoubtedly one of the major physiological cNMPs...
February 18, 2017: Handbook of Experimental Pharmacology
https://www.readbyqxmd.com/read/28213537/ketoacylsynthase-domains-of-a-pufa-synthase-in-thraustochytrium-can-effectively-function-as-stand-alone-enzymes-in-escherichia-coli
#16
Xi Xie, Dauenpen Meesapyodsuk, Xiao Qiu
Thraustochytrium sp. 26185 accumulates a high level of docosahexaenoic acid (DHA), a nutritionally important ω-3 very long chain unsaturated fatty acid (VLCPUFA) synthesized primarily by polyunsaturated fatty acid (PUFA) synthase, a Type I polyketide synthase-like mega-enzyme. The PUFA synthase in this species comprises three large subunits each with multiple catalytic domains. It was hypothesized that among these domains, ketoacylsynthase (KS) domains might be critical for catalyzing the condensation of specific unsaturated acyl-ACPs with malonyl-ACP, whereby retaining double bonds in an extended acyl chain...
February 17, 2017: Applied and Environmental Microbiology
https://www.readbyqxmd.com/read/28213286/investigation-of-silicon-carbon-nitride-nanocomposite-films-as-a-wear-resistant-layer-in-vitro-and-in-vivo-for-joint-replacement-applications
#17
Y Liang, D G Liu, W Q Bai, J P Tu
Silicon-contained CNx nanocomposite films were prepared using the ion beam assisted magnetron sputtering under different nitrogen gas pressure. With increase of the nitrogen pressure, silicon and nitrogen content of the CNx films drastically increase, and is saturated as the PN2 reach about 40%. Surface roughness and the contact angle are increase, while the friction coefficient decreased. The CNx film with 5.7at.% Si content possess the lowest friction coefficient of only 0.07, and exhibited the best tribological properties...
February 10, 2017: Colloids and Surfaces. B, Biointerfaces
https://www.readbyqxmd.com/read/28213139/antimycobacterial-antimicrobial-activity-experimental-ft-ir-ft-raman-nmr-uv-vis-dsc-and-dft-transition-state-chemical-reactivity-nbo-nlo
#18
Poonam Rawat, R N Singh, Alok Ranjan, Sartaj Ahmad, Rajat Saxena
As part of a study of pyrrole hydrazone, we have investigated quantum chemical calculations, molecular geometry, relative energy, vibrational properties and antimycobacterial/antimicrobial activity of pyrrole-2-carboxaldehyde isonicotinyl hydrazone (PCINH), by applying the density functional theory (DFT) and Hartree Fock (HF). Good reproduction of experimental values is obtained and with small percentage error in majority of the cases in comparison to theoretical result (DFT). The experimental FT-IR and Raman wavenumbers were compared with the respective theoretical values obtained from DFT calculations and found to agree well...
February 11, 2017: Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
https://www.readbyqxmd.com/read/28213132/surveillance-or-engagement-children-s-conflicts-during-health-maintenance-visits
#19
Sarah Polk, Russell Horwitz, Shaina Longway, Alfonso Bonilla, Kate Fothergill, Marc Karver, Peter Salmon, Lawrence Wissow
OBJECTIVE: School-aged health maintenance visits seek to prevent or intervene early with health issues of life-long importance. Little is known about what children expect to happen in these visits or how they experience them, factors related to their engagement as active collaborators in care. METHODS: Thirty children (53% Latino, 27% African-American and 20% White) age 7-11 years were video recorded during a health maintenance visit and then interviewed while reviewing the videos...
February 14, 2017: Academic Pediatrics
https://www.readbyqxmd.com/read/28212929/structural-analysis-of-a-homogeneous-polysaccharide-from-achatina-fulica
#20
Jie Liu, Feigneng Shang, Zengming Yang, Mingyi Wu, Jinhua Zhao
Edible snails have been widely used as a health food and medicine in many countries. In our study, a water-soluble polysaccharide (AF-1) was isolated and purified from Achatina fulica by papain enzymolysis, alcohol precipitation and strong anion exchange chromatography. Structural of the polysaccharide was analyzed and characterized by chemical and instrumental methods, such as Fourier transform infrared spectroscopy, high performance liquid chromatography, analysis of monosaccharide composition, methylation analysis, and nuclear magnetic resonance (NMR) spectroscopy ((1)H, (13)C, COSY, TOCSY, NOESY, HSQC and HMBC)...
February 14, 2017: International Journal of Biological Macromolecules
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