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https://www.readbyqxmd.com/read/28549890/-18-f-labeled-indole-based-analogs-as-highly-selective-radioligands-for-imaging-sigma-2-receptors-in-the-brain
#1
Liang Wang, Jiajun Ye, Yingfang He, Winnie Deuther-Conrad, Jinming Zhang, Xiaojun Zhang, Mengchao Cui, Jörg Steinbach, Yiyun Huang, Peter Brust, Hongmei Jia
We have designed and synthesized a series of indole-based σ2 receptor ligands containing 5,6-dimethoxyisoindoline or 6,7-dimethoxy-1,2,3,4-tetrahydroisoquinoline as pharmacophore. In vitro competition binding assays showed that all ten ligands possessed low nanomolar affinity (Ki=1.79-5.23nM) for σ2 receptors and high subtype selectivity (Ki (σ2)/Ki (σ1)=56-708). Moreover, they showed high selectivity for σ2 receptor over the vesicular acetylcholine transporter (>1000-fold). The corresponding radiotracers [(18)F]16 and [(18)F]21 were prepared by an efficient one-pot, two-step reaction sequence with a home-made automated synthesis module, with 10-15% radiochemical yield and radiochemical purity of >99%...
May 10, 2017: Bioorganic & Medicinal Chemistry
https://www.readbyqxmd.com/read/28549090/sigma-1-receptor-regulates-mitochondrial-function-in-glucose-and-oxygen-deprived-retinal-ganglion-cells
#2
Dorette Z Ellis, Linya Li, Yong Park, Shaoqing He, Brett Mueller, Thomas Yorio
Purpose: Understanding the role of mitochondria in retinal ganglion cells (RGCs) is relevant to human disease as studies have shown mitochondrial abnormalities in primary open-angle glaucoma patients. This study seeks to determine the effects of the sigma-1 receptor (σ-1r) and its agonists on mitochondrial function in oxygen- and glucose- deprived (OGD) purified neonatal RGCs. Methods: Retinal ganglion cells were isolated from rat pups and subjected to OGD in varying conditions in the presence or absence of σ-1r agonist and antagonist and following addition of an AAV2-σ-1r vector that was used to increase σ-1r expression...
May 1, 2017: Investigative Ophthalmology & Visual Science
https://www.readbyqxmd.com/read/28548604/quorum-sensing-systems-in-the-plant-growth-promoting-bacterium-paraburkholderia-phytofirmans-psjn-exhibit-cross-regulation-and-are-involved-in-biofilm-formation
#3
Ana Zúñiga, Raúl A Donoso, Daniela Ruiz, Gonzalo A Ruz, Bernardo González
Quorum-sensing systems play important roles in host colonization and host establishment of Burkholderiales species. Beneficial Paraburkholderia species share a conserved quorum-sensing (QS) system, designated BraI/R, that controls different phenotypes. In this context, the plant growth-promoting bacterium Paraburkholderia phytofirmans PsJN possesses two different homoserine lactone QS systems BpI.1/R.1 and BpI.2/R.2 (BraI/R-like QS system). The BpI.1/R.1 QS system was previously reported to be important to colonize and produce beneficial effects in Arabidopsis thaliana plants...
May 26, 2017: Molecular Plant-microbe Interactions: MPMI
https://www.readbyqxmd.com/read/28548042/new-insights-into-reovirus-evolution-implications-from-a-newly-characterized-mycoreovirus
#4
Lijiang Liu, Jiasen Cheng, Yanping Fu, Huiquan Liu, Daohong Jiang, Jiatao Xie
We performed molecular cloning and complete genome sequencing of a novel mycoreovirus, Sclerotinia sclerotiorumreovirus 1 (SsReV1), isolated from an isolate of the phytopathogenic fungus Sclerotinia sclerotiorum. SsReV1 has a genome of 28 055 bp and is composed of 11 double-stranded RNA segments. With a combination of unique molecular features, virion shape and composition, and phylogenetic analysis, SsReV1 is significantly distinct from all known reoviruses and defines a novel genus in the family Reoviridae...
May 26, 2017: Journal of General Virology
https://www.readbyqxmd.com/read/28545064/transcriptomic-analysis-of-the-response-of-pseudomonas-fluorescens-to-epigallocatechin-gallate-by-rna-seq
#5
Xiaoxiang Liu, Bimiao Shen, Peng Du, Nan Wang, Jiaxue Wang, Jianrong Li, Aihua Sun
Epigallocatechin gallate (EGCG) is a main constituent of green tea polyphenols that are widely used as food preservatives and are considered to be safe for consumption. However, the underlying antimicrobial mechanism of EGCG and the bacterial response to EGCG are not clearly understood. In the present study, a genome-wide transcriptional analysis of a typical spoilage bacterium, Pseudomonas fluorescens that responded to EGCG was performed using RNA-seq technology. A total of 26,365,414 and 23,287,092 clean reads were generated from P...
2017: PloS One
https://www.readbyqxmd.com/read/28544475/thiazole-based-sigma-1-receptor-ligands-diversity-by-late-stage-c-h-arylation-of-thiazoles-structure-affinity-and-selectivity-relationships-and-molecular-interactions
#6
Bernhard Wünsch, Artur Kokornaczyk, Dirk Schepmann, Junichiro Yamaguchi, Kenichiro Itami, Erik Laurini, Maurizio Fermeglia, Sabrina Pricl
Spirocyclic thiophene derivatives represent promising sigma-1 ligands with high sigma-1 affinity and selectivity over the sigma-2 subtype. In order to increase ligand efficiency, the thiophene ring was replaced bioisosterically by a thiazole ring and the pyran ring was opened. Late-stage diversification by regioselective C-H arylation of thiazoles 9a-c resulted in a set of 53 compounds with high diversity. This set of compounds was analyzed with respect to sigma-1 affinity, sigma-1/sigma-2 selectivity, lipophilicity (logD7...
May 24, 2017: ChemMedChem
https://www.readbyqxmd.com/read/28538055/high-reliability-principles-must-be-tied-to-value-based-outcomes
#7
Mitchell L Wasden
WellStar Health System and the Medical University of South Carolina (MUSC), highlighted in this issue's feature articles, are two organizations seeking to drive high reliability by educating leaders and incorporating high-reliability principles into their quality improvement (QI) efforts. The organizations have taken slightly different approaches to executing on high reliability, yet both are encouraged by the apparent success of high-reliability principles in other industries.The high-reliability framework is often applied to healthcare despite the limitations of comparing healthcare organizations to nuclear reactors, commercial airlines, and aircraft carriers...
July 2017: Frontiers of Health Services Management
https://www.readbyqxmd.com/read/28537605/factors-affecting-bubble-size-in-ionic-liquids
#8
Sarah F R Taylor, Stuart A Brittle, Pratik Desai, Johan Jacquemin, Christopher Hardacre, William A Zimmerman
This study reports on understanding the formation of bubbles in ionic liquids (ILs), with a view to utilising ILs more efficiently in gas capture processes. In particular, the impact of the IL structure on the bubble sizes obtained has been determined in order to obtain design principles for the ionic liquids utilised. 11 ILs were used in this study with a range of physico-chemical properties in order to determine parametrically the impact on bubble size due to the liquid properties and chemical moieties present...
May 24, 2017: Physical Chemistry Chemical Physics: PCCP
https://www.readbyqxmd.com/read/28536573/mqsr-mqsa-toxin-antitoxin-system-regulates-persistence-and-biofilm-formation-in-pseudomonas-putida-kt2440
#9
Chenglong Sun, Yunxue Guo, Kaihao Tang, Zhongling Wen, Baiyuan Li, Zhenshun Zeng, Xiaoxue Wang
Bacterial toxin/antitoxin (TA) systems have received increasing attention due to their prevalence, diverse structures, and important physiological functions. In this study, we identified and characterized a type II TA system in a soil bacterium Pseudomonas putida KT2440. This TA system belongs to the MqsR/MqsA family. We found that PP_4205 (MqsR) greatly inhibits cell growth in P. putida KT2440 and Escherichia coli, the antitoxin PP_4204 (MqsA) neutralizes the toxicity of the toxin MqsR, and the two genes encoding them are co-transcribed...
2017: Frontiers in Microbiology
https://www.readbyqxmd.com/read/28535957/improving-oil-classification-quality-from-oil-spill-fingerprint-beyond-six-sigma-approach
#10
Hafizan Juahir, Azimah Ismail, Saiful Bahri Mohamed, Mohd Ekhwan Toriman, Azlina Md Kassim, Sharifuddin Md Zain, Wan Kamaruzaman Wan Ahmad, Wong Kok Wah, Munirah Abdul Zali, Ananthy Retnam, Mohd Zaki Mohd Taib, Mazlin Mokhtar
This study involves the use of quality engineering in oil spill classification based on oil spill fingerprinting from GC-FID and GC-MS employing the six-sigma approach. The oil spills are recovered from various water areas of Peninsular Malaysia and Sabah (East Malaysia). The study approach used six sigma methodologies that effectively serve as the problem solving in oil classification extracted from the complex mixtures of oil spilled dataset. The analysis of six sigma link with the quality engineering improved the organizational performance to achieve its objectivity of the environmental forensics...
May 20, 2017: Marine Pollution Bulletin
https://www.readbyqxmd.com/read/28531970/ultrasensitive-cholesterol-biosensor-based-on-enzymatic-silver-deposition-on-gold-nanoparticles-modified-screen-printed-carbon-electrode
#11
Yong Huang, Lijie Cui, Yewei Xue, Songbai Zhang, Nixuan Zhu, Jintao Liang, Guiyin Li
Cholesterol is one of the essential structural constituents of cell membranes. Determination of cholesterol is of great importance in clinical analysis because the level of cholesterol in serum is an indicator in the diagnosis and prevention of heart diseases. In this work, a simple and ultrasensitive cholesterol biosensor based on enzymatic silver deposition was designed by immobilizing cholesterol oxidase (CHOD) and cholesterol esterase (CHER) onto the surface of gold nanoparticles (Au NPs) modified screen-printed carbon electrode (SPE)...
August 1, 2017: Materials Science & Engineering. C, Materials for Biological Applications
https://www.readbyqxmd.com/read/28531088/influence-of-patient-mispositioning-on-sar-distribution-and-simulated-temperature-in-regional-deep-hyperthermia
#12
Bassim Aklan, Pia Gierse, Josefin Hartmann, Oliver J Ott, Rainer Fietkau, Christoph Bert
Patient positioning plays an important role in regional deep hyperthermia to obtain a successful hyperthermia treatment. In this study, the influence of possible patient mispositioning was systematically assessed on specific absorption rate (SAR) and temperature distribution. With a finite difference time domain approach, the SAR and temperature distributions were predicted for six patients at 312 positions. Patient displacements and rotations as well as the combination of both were considered inside the Sigma-Eye applicator...
May 22, 2017: Physics in Medicine and Biology
https://www.readbyqxmd.com/read/28526787/development-of-multi-well-plate-methods-using-pure-cultures-of-methanogens-to-identify-new-inhibitors-for-suppressing-ruminant-methane-emissions
#13
M R Weimar, J Cheung, D Dey, C McSweeney, M Morrison, Y Kobayashi, W B Whitman, V Carbone, L R Schofield, R S Ronimus, G M Cook
Hydrogenotrophic methanogens typically require strictly anaerobic culturing conditions in glass tubes with overpressures of H2 and CO2 that are both time-consuming and costly. To increase the throughput for screening chemical compound libraries, 96-well microtiter plate methods for the growth of a marine (environmental) methanogen Methanococcus maripaludis strain S2 and the rumen methanogen Methanobrevibacter species AbM4 were developed. A number of key parameters (inoculum size, reducing agents for media preparation, duration of assay, inhibitor solvents and culture volume) were optimised to achieve robust and reproducible growth in a high-throughput microtiter plate format...
May 19, 2017: Applied and Environmental Microbiology
https://www.readbyqxmd.com/read/28526785/effects-of-arginine-on-growth-virulence-gene-expression-and-stress-tolerance-by-streptococcus-mutans
#14
Brinta Chakraborty, Robert A Burne
Streptococcus mutans is a common constituent of oral biofilms and a primary etiologic agent of human dental caries. The bacteria associated with dental caries have a potent ability to produce organic acids from dietary carbohydrates and to grow and metabolize in acidic conditions. In contrast, many commensal bacteria produce ammonia through the arginine deiminase system (ADS), which moderates the pH of oral biofilms. Arginine metabolism by the ADS is a significant deterrent to the initiation and progression of dental caries...
May 19, 2017: Applied and Environmental Microbiology
https://www.readbyqxmd.com/read/28525360/role-of-sigma-1-receptor-in-high-fat-diet-induced-peripheral-neuropathy
#15
Tieying Song, Jianhui Zhao, Xiaojing Ma, Zaiwang Zhang, Bo Jiang, Yunliang Yang
The neurobiological mechanisms of obesity-induced peripheral neuropathy are poorly understood. We evaluated the role of Sigma-1 receptor (Sig-1R) and NMDA receptor (NMDARs) in the spinal cord in peripheral neuropathy using an animal model of high fat diet-induced diabetes. We examined the expression of Sig-1R and NMDAR subunits GluN2A and GluN2B along with postsynaptic density protein 95 (PSD-95) in the spinal cord after 24- week HFD treatment in both wild-type and Sig-1R-/- mice. Finally, we examined the effects of repeated intrathecal administrations of selective Sig-1R antagonists BD1047 in HFD-fed wild-type mice on peripheral neuropathy...
May 19, 2017: Biological Chemistry
https://www.readbyqxmd.com/read/28524089/green-synthesized-zinc-oxide-zno-nanoparticles-induce-oxidative-stress-and-dna-damage-in-lathyrus-sativus-l-root-bioassay-system
#16
Kamal K Panda, Dambaru Golari, A Venugopal, V Mohan M Achary, Ganngam Phaomei, Narasimham L Parinandi, Hrushi K Sahu, Brahma B Panda
Zinc oxide nanoparticles (ZnONP-GS) were synthesised from the precursor zinc acetate (Zn(CH₃COO)₂) through the green route using the milky latex from milk weed (Calotropis gigantea L. R. Br) by alkaline precipitation. Formation of the ZnONP-GS was monitored by UV-visible spectroscopy followed by characterization and confirmation by energy-dispersive X-ray spectroscopy (EDX), transmission electron microscopy (TEM), and X-ray diffraction (XRD). Both the ZnONP-GS and the commercially available ZnONP-S (Sigma-Aldrich) and cationic Zn(2+) from Zn(CH₃COO)₂ were tested in a dose range of 0-100 mg·L(-1) for their potency (i) to induce oxidative stress as measured by the generation reactive oxygen species (ROS: O₂(•-), H₂O₂ and (•)OH), cell death, and lipid peroxidation; (ii) to modulate the activities of antioxidant enzymes: catalase (CAT), superoxide dismutase (SOD), guaiacol peroxidase (GPX), and ascorbate peroxidase (APX); and (iii) to cause DNA damage as determined by Comet assay in Lathyrus sativus L...
May 18, 2017: Antioxidants (Basel, Switzerland)
https://www.readbyqxmd.com/read/28522802/proteome-remodelling-by-the-stress-sigma-factor-rpos-%C3%AF-s-in-salmonella-identification-of-small-proteins-and-evidence-for-post-transcriptional-regulation
#17
Magali Lago, Véronique Monteil, Thibaut Douche, Julien Guglielmini, Alexis Criscuolo, Corinne Maufrais, Mariette Matondo, Françoise Norel
The RpoS/σ(S) sigma subunit of RNA polymerase is the master regulator of the general stress response in many Gram-negative bacteria. Extensive studies have been conducted on σ(S)-regulated gene expression at the transcriptional level. In contrast, very limited information regarding the impact of σ(S) on global protein production is available. In this study, we used a mass spectrometry-based proteomics approach to explore the wide σ(S)-dependent proteome of the human pathogen Salmonella enterica serovar Typhimurium...
May 18, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28512454/new-insights-into-the-regulation-of-cell-surface-signaling-activity-acquired-from-a-mutagenesis-screen-of-the-pseudomonas-putida-iuty-sigma-anti-sigma-factor
#18
Karlijn C Bastiaansen, Cristina Civantos, Wilbert Bitter, María A Llamas
Cell-surface signaling (CSS) is a signal transfer system that allows Gram-negative bacteria to detect environmental signals and generate a cytosolic response. These systems are composed of an outer membrane receptor that senses the inducing signal, an extracytoplasmic function sigma factor (σ(ECF)) that targets the cytosolic response by modifying gene expression and a cytoplasmic membrane anti-sigma factor that keeps the σ(ECF) in an inactive state in the absence of the signal and transduces its presence from the outer membrane to the cytosol...
2017: Frontiers in Microbiology
https://www.readbyqxmd.com/read/28507242/an-rpohi-dependent-response-promotes-outgrowth-after-extended-stationary-phase-in-the-alphaproteobacterium-rhodobacter-sphaeroides
#19
B Remes, T Rische-Grahl, K M H Müller, K U Förstner, Y Sung-Huan, L Weber, A Jäger, V Peuser, G Klug
Under unfavorable growth conditions, bacteria enter stationary phase and can maintain cell viability over prolonged periods with no increase in cell number. To get insights into the regulatory mechanisms that allow bacteria to resume growth when conditions become favorable again (outgrowth) we performed global transcriptome analyses at different stages of growth for the alphaproteobacterium Rhodobacter sphaeroides The majority of genes was not differentially expressed across growth phases. After short stationary phase (about 20 h after growth starts to slow down), only 7 % of the genes showed altered expression (fold change of > 1...
May 15, 2017: Journal of Bacteriology
https://www.readbyqxmd.com/read/28507241/an-amino-acid-substitution-in-rna-polymerase-that-inhibits-the-utilization-of-an-alternative-sigma-factor
#20
Anna F Wang Erickson, Padraig Deighan, Cinthia P Garcia, Robert O J Weinzierl, Ann Hochschild, Richard Losick
Sigma (σ) factors direct gene transcription by binding to and determining the promoter recognition specificity of RNA polymerase (RNAP) in bacteria. Genes transcribed under the control of alternative sigma factors allow cells to respond to stress and undergo developmental processes such as sporulation in Bacillus subtilis, in which gene expression is controlled by a cascade of alternative sigma factors. Binding of sigma factors to RNA polymerase depends on the coiled-coil (or clamp helices) motif of the β' subunit...
May 15, 2017: Journal of Bacteriology
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