keyword
MENU ▼
Read by QxMD icon Read
search

19F

keyword
https://www.readbyqxmd.com/read/28324771/synthesis-and-conformational-analysis-of-a-simplified-inositol-model-of-the-streptococcus-pneumoniae-19f-capsular-polysaccharide-repeating-unit
#1
Giorgio Catelani, Felicia D'Andrea, Lorenzo Guazzelli, Alessio Griselli, Nicola Testi, Maria Assunta Chiacchio, Laura Legnani, Lucio Toma
Carbohydrate mimics have been studied for a long time as useful sugar substitutes, both in the investigation of biological events and in the treatment of sugar-related diseases. Here we report further evaluation of the capabilities of inositols as carbohydrate substitutes. The conformational features of an inositol-model of a simplified repeating unit corresponding to the capsular polysaccharide of Streptococcus pneumoniae 19F has been evaluated by computational analysis, and compared to the native repeating unit...
March 14, 2017: Carbohydrate Research
https://www.readbyqxmd.com/read/28318766/bacille-calmette-gu%C3%A3-rin-bcg-vaccination-at-birth-and-antibody-responses-to-childhood-vaccines-a-randomised-clinical-trial
#2
Thomas Nørrelykke Nissen, Nina Marie Birk, Gaby Smits, Dorthe Lisbeth Jeppesen, Lone Graff Stensballe, Mihai G Netea, Fiona van der Klis, Christine Stabell Benn, Ole Pryds
INTRODUCTION: BCG vaccination has been associated with beneficial non-specific effects on child health. Some immunological studies have reported heterologous effects of vaccines on antibody responses to heterologous vaccines. Within a randomised clinical trial of Bacille Calmette-Guérin (BCG) vaccination at birth, The Danish Calmette Study, we investigated the effect of BCG at birth on the antibody response to the three routine vaccines against DiTeKiPol/Act-Hib and Prevenar 13 in a subgroup of participants...
March 15, 2017: Vaccine
https://www.readbyqxmd.com/read/28303826/prevalence-of-pneumococcal-serotypes-in-adults-%C3%A2-50-years-of-age
#3
Chand Wattal, Neeraj Goel, S P Byotra
CONTEXT: Currently, majority of studies on antibiotic resistance and serotype prevalence in Streptococcus pneumoniae are in paediatric population and there is limited epidemiologic data pertaining to elderly Indian population. AIMS: This study was undertaken to assess antibiotic resistance pattern and the coverage of the polysaccharide vaccine 23 (PPV23) in the elderly population. SETTINGS AND DESIGN: This was a prospective 2-year pneumococcal surveillance study in patients with community-acquired pneumococcal infections of ≥50 years' age group on fifty isolates of S...
January 2017: Indian Journal of Medical Microbiology
https://www.readbyqxmd.com/read/28267311/model-free-analysis-of-critical-micellar-concentrations-for-detecting-demixing-in-surfactant-mixtures
#4
Erik Frotscher, Jonas Höring, Grégory Durand, Carolyn Vargas, Sandro Keller
Aqueous mixtures of two or more surfactants are often employed for research or industrial purposes because such mixtures offer advantages over single-surfactant systems. This is particularly true for mixtures of fluorocarbon (FC) and hydrocarbon (HC) surfactants, which display a broad range of mutual miscibilities in mixed micelles. Unfortunately, the prediction and even the experimental elucidation of the micellar mixing behavior of surfactant mixtures remain challenging, as evidenced by conflicting results and conclusions derived from diverse, and often complex, mixing models...
March 21, 2017: Analytical Chemistry
https://www.readbyqxmd.com/read/28264733/pneumococcal-nasopharyngeal-carriage-among-children-in-brazil-prior-to-the-introduction-of-the-10-valent-conjugate-vaccine-a-culture-and-pcr-based-survey
#5
H G Rodrigues, T C A Pinto, R R Barros, L M Teixeira, F P G Neves
We performed two different approaches (broth enrichment step prior to culture (BEC) and PCR (BEPCR)) for detecting Streptococcus pneumoniae from nasopharyngeal specimens collected from 242 children aged <6 years attending one hospital (n = 140) and one childcare centre (n = 102) in a major urban area in Brazil. These specimens were collected immediately before the introduction of the 10-valent pneumococcal conjugate vaccine (PCV10) and the 13-valent vaccine (PCV13) for routine use in Brazil. Results were compared with previous findings obtained with direct culture (DC) on a selective medium...
March 7, 2017: Epidemiology and Infection
https://www.readbyqxmd.com/read/28261176/nasopharyngeal-and-oropharyngeal-colonization-by-staphylococcus-aureus-and-streptococcus-pneumoniae-and-prognostic-markers-in-children-with-sickle-cell-disease-from-the-northeast-of-brazil
#6
Larissa C Rocha, Magda O S Carvalho, Valma M L Nascimento, Milena S Dos Santos, Tânia F Barros, Elisângela V Adorno, Joice N Reis, Caroline C da Guarda, Rayra P Santiago, Marilda de Souza Gonçalves
We investigated the nasopharynx and oropharynx microbiota in sickle cell disease (SCD) to identify the microorganisms, antibiotic sensitivity, prevalent serotypes, and association of with laboratorial markers. Oropharynx/nasopharynx secretions were investigated in 143 SCD children aging 6 months to 17 years. Pathogens were isolated using standard procedures, and laboratorial markers were performed by automated methods. Staphylococcus aureus (S. aureus) was isolated from nasopharynx and oropharynx of 64 and of 17 SCD children respectively...
2017: Frontiers in Microbiology
https://www.readbyqxmd.com/read/28246190/phosphorylation-of-g-protein-coupled-receptors-from-the-barcode-hypothesis-to-the-flute-model
#7
Zhao Yang, Fan Yang, Daolai Zhang, Zhixin Liu, Amy Lin, Chuan Liu, Peng Xiao, Xiao Yu, Jin-Peng Sun
Seven transmembrane G protein-coupled receptors (GPCRs) are often phosphorylated at the C-terminus and on intracellular loops in response to various extracellular stimuli. Phosphorylation of GPCRs by GPCR kinases (GRKs) and certain other kinases can promote the recruitment of arrestin molecules. The arrestins critically regulate GPCR functions, not only by mediating receptor desensitization and internalization, but also by redirecting signalling to G protein-independent pathways via interactions with numerous downstream effector molecules...
February 28, 2017: Molecular Pharmacology
https://www.readbyqxmd.com/read/28230365/catalytic-enantioselective-2-3-rearrangements-of-allylic-ammonium-ylides-a-mechanistic-and-computational-study
#8
Thomas H West, Daniel M Walden, James E Taylor, Alexander C Brueckner, Ryne C Johnston, Paul Ha-Yeon Cheong, Guy C Lloyd-Jones, Andrew D Smith
A mechanistic study of the isothiourea-catalyzed enantioselective [2,3]-rearrangement of allylic ammonium ylides is described. Reaction kinetic analyses using (19)F NMR and density functional theory computations have elucidated a reaction profile and allowed identification of the catalyst resting state and turnover-rate limiting step. A catalytically relevant catalyst-substrate adduct has been observed, and its constitution elucidated unambiguously by (13)C and (15)N isotopic labeling. Isotopic entrainment has shown the observed catalyst-substrate adduct to be a genuine intermediate on the productive cycle toward catalysis...
March 10, 2017: Journal of the American Chemical Society
https://www.readbyqxmd.com/read/28224673/orthogonal-click-postfunctionalization-of-alternating-copolymers-prepared-by-nitroxide-mediated-polymerization
#9
Matthias Tesch, Sergej Kudruk, Matthias Letzel, Armido Studer
Nitroxide Mediated Polymerization (NMP) was applied to prepare alternating copolymers using 1,1,1,3,3,3-hexafluoroisopropyl acrylate (HFIPA) 1 and ((6-trimethylsilyl)-hex-5-yn-1-yl)vinyl ether (THVE) 2 as monomers. The alternating sequence of the resulting poly(HFIPA-alt-THVE) 3 was proved via tandem mass spectrometry (MS/MS) and further supported by 1H NMR spectroscopy. Alternating alkyne and activated ester moieties of copolymer 3 were further functionalized with organic azides and amines using sequential Cu-catalyzed azide-alkyne click (CuAAC) and amidation reactions, providing dually functionalized poly(acrylamide-alt-triazole) polymers 5...
February 22, 2017: Chemistry: a European Journal
https://www.readbyqxmd.com/read/28221772/desleucyl-oritavancin-with-a-damaged-d-ala-d-ala-binding-site-inhibits-the-transpeptidation-step-of-cell-wall-biosynthesis-in-whole-cells-of-staphylococcus-aureus
#10
Sung Joon Kim, Manmilan Singh, Shasad Sharif, Jacob Schaefer
We have used solid-state nuclear magnetic resonance to characterize the exact nature of the dual mode of action of oritavancin in preventing cell-wall assembly in Staphylococcus aureus. Measurements performed on whole cells labeled selectively in vivo have established that des-N-methylleucyl-N-4-(4-fluorophenyl)benzyl-chloroeremomycin, an Edman degradation product of [(19)F]oritavancin, which has a damaged d-Ala-d-Ala binding aglycon, is a potent inhibitor of the transpeptidase activity of cell-wall biosynthesis...
March 14, 2017: Biochemistry
https://www.readbyqxmd.com/read/28216405/design-synthesis-and-biological-evaluation-of-nonsecosteroidal-vitamin-d3-receptor-ligands-as-anti-tumor-agents
#11
Bin Wang, Meixi Hao, Can Zhang
1α,25-dihydroxyvitamin D3 (1,25-(OH)2D3, also known as calcitriol), the active form of vitamin D3, is being increasingly recognized for cancer therapy. Our previous work showed that phenyl-pyrrolyl pentane analogs, which mimicked anti-proliferative activities against several cancer cell lines of the natural secosteroidal ligand 1,25-(OH)2D3. Here, in order to optimize the structural features and discover more potent derivative, a series of nonsecosteroidal vitamin D3 receptor (VDR) ligands bearing acetylene bond linker was designed, synthesized and evaluated...
February 1, 2017: Bioorganic & Medicinal Chemistry Letters
https://www.readbyqxmd.com/read/28215915/serotype-distribution-and-antimicrobial-susceptibility-of-streptococcus-pneumoniae-isolates-from-adult-patients-in-jakarta-indonesia
#12
Wahyu Finasari Said, Edy Sukoto, Miftahuddin Majid Khoeri, July Kumalawati, Dodi Safari
Currently, the data on pneumococcal invasive disease in the Indonesian population are limited. In this study, we investigated the serotype distribution and antimicrobial susceptibility of Streptococcus pneumoniae. These samples were isolated from the sputum of adult patients with non-specific clinical symptoms aged 18-87 years in Jakarta, Indonesia, from August to October 2014. Of the 349 sputum specimens, thirteen isolates were identified as S. pneumoniae strains (4%), with two strains each for serotype 19F, 3, and 15A, and one strain each for serotype/serogroup 13, 23A, 6, 34, 17F, 16F, and untypeable...
February 16, 2017: Journal of Infection and Public Health
https://www.readbyqxmd.com/read/28198587/hexaphyrin-as-a-potential-theranostic-dye-for-photothermal-therapy-and-19f-magnetic-resonance-imaging
#13
Tomohiro Higashino, Hirotaka Nakatsuji, Ryosuke Fukuda, Haruki Okamoto, Hirohiko Imai, Tetsuya Matsuda, Hidehito Tochio, Masahiro Shirakawa, Nikolai Tkachenko, Mitsuru Hashida, Tatsuya Murakami, Hiroshi Imahori
meso-Aryl substituted expanded porphyrins have two potential key features suitable for theranostic agents, excellent absorption in near infrared (NIR) region and possible introduction of multiple fluorine atoms at structurally nearly equivalent positions. Herein, hexaphyrin (hexa) was synthesized using 2,6-bis(trifluoromethyl)-4-formyl benzoate and pyrrole and evaluated as a novel theranostic expanded porphyrin possessing the above key features. Under NIR light illumination hexa showed intense photothermal and weak photodynamic effects, which were most likely due to its low-lying excited states close to a singlet oxygen...
February 15, 2017: Chembiochem: a European Journal of Chemical Biology
https://www.readbyqxmd.com/read/28195380/small-molecule-mixture-analysis-by-heteronuclear-nmr-under-spin-diffusion-conditions-in-viscous-dmso-water-solvent
#14
Pedro Lameiras, Solène Patis, Jouda Jakhlal, Stéphanie Castex, Pascale Clivio, Jean-Marc Nuzillard
Spin diffusion in NMR occurs for small- and medium-sized molecules when their tumbling rate reduces in solution so that magnetization exchange by longitudinal cross relaxation becomes highly efficient. Composite DMSO-water viscous solvents were used for the first time to access the individual NMR spectra of a mixture components in spin diffusion conditions. The easy handling and high dissolution power of [D6 ]DMSO/H2 O offers a wide range of potential applications for polar and moderately apolar mixture analysis...
February 13, 2017: Chemistry: a European Journal
https://www.readbyqxmd.com/read/28187060/risk-factors-in-children-older-than-5-years-with-pneumococcal-meningitis-data-from-a-national-network
#15
Fanny Hénaff, Corinne Levy, Robert Cohen, Capucine Picard, Emmanuelle Varon, Christèle Gras Le Guen, Elise Launay
INTRODUCTION: The occurrence of meningitis in children > 5 years old may be associated with specific predisposing factors that can be anatomic, such as cerebrospinal fluid (CSF) fistula or breach, or related to genetic susceptibility or N inborn or acquired immunologic defect. This study aimed to assess the anatomical and immunologic risk factors in children > 5 years old with pneumococcal meningitis and prospectively enrolled in the French national meningitis network. METHODS: We analyzed all data for children 5 to 15 years old with a diagnosis of pneumococcal meningitis between 2001 and 2013...
December 13, 2016: Pediatric Infectious Disease Journal
https://www.readbyqxmd.com/read/28180296/characterization-of-human-telomere-rna-g-quadruplex-structures-in-vitro-and-in-living-cells-using-19f-nmr-spectroscopy
#16
Hong-Liang Bao, Takumi Ishizuka, Takashi Sakamoto, Kenzo Fujimoto, Tamayo Uechi, Naoya Kenmochi, Yan Xu
No abstract text is available yet for this article.
February 9, 2017: Nucleic Acids Research
https://www.readbyqxmd.com/read/28178935/pneumococcal-carriage-among-hiv-infected-children-in-accra-ghana
#17
Eric S Donkor, Jennifer A Annan, Ebenezer V Badoe, Nicholas T K D Dayie, Appiah-Korang Labi, Hans-Christian Slotved
BACKGROUND: Pneumococcal carriage is the precursor for development of pneumococcal disease, and is also responsible for transmission of the organism from person-to-person. In Africa, little is known about the pneumococcus in relation to people with HIV infection. The aim of the study was to investigate the epidemiology of pneumococcal carriage among HIV infected children visiting a tertiary hospital in Ghana, including the carriage prevalence, risk factors and serotype distribution. METHOD: This was a cross sectional study carried out from February to May, 2015 at the HIV Paediatric Clinic of the Korle-Bu Teaching Hospital in Accra, Ghana...
February 8, 2017: BMC Infectious Diseases
https://www.readbyqxmd.com/read/28178138/etiology-of-acute-otitis-media-and-serotype-distribution-of-streptococcus-pneumoniae-and-haemophilus-influenzae-in-chilean-children-5-years-of-age
#18
Andres Rosenblut, Carla Napolitano, Angelica Pereira, Camilo Moreno, Devayani Kolhe, Alejandro Lepetic, Eduardo Ortega-Barria
The impact of bacterial conjugate vaccines on acute otitis media (AOM) is affected by several factors including population characteristics, bacterial etiology and vaccine conjugation method, carrier, and coverage. This study estimated the baseline etiology, distribution, and antibiotic susceptibility of bacterial serotypes that causes AOM in children aged <5 years in a public setting in Santiago, Chile.Children aged ≥3 months and <5 years referred to the physician for treatment of AOM episodes (with an onset of symptoms <72 h) were enrolled between September 2009 and September 2010...
February 2017: Medicine (Baltimore)
https://www.readbyqxmd.com/read/28165731/novel-experimental-modeling-approach-for-characterizing-perfluorinated-surfactants-in-soils
#19
Denis Courtier-Murias, Eric Michel, Stéphane Rodts, François Lafolie
Soil contamination is still poorly understood and modeled in part because of the difficulties of looking inside the "black box" constituted by soils. Here, we investigated the application of a recently developed (1)H NMR technique to (19)F NMR relaxometry experiments and utilized the results as inputs for an existing model. This novel approach yields (19)F T2 NMR relaxation values of any fluorinated contaminant, which are among the most dangerous contaminants, allowing us to noninvasively and directly monitor their fate in soils...
February 16, 2017: Environmental Science & Technology
https://www.readbyqxmd.com/read/28165218/perfluoro-tert-butyl-homoserine-is-a-helix-promoting-highly-fluorinated-nmr-sensitive-aliphatic-amino-acid-detection-of-the-estrogen-receptor%C3%A2-coactivator-protein-protein-interaction-by-19-f-nmr
#20
Caitlin M Tressler, Neal J Zondlo
Highly fluorinated amino acids can stabilize proteins and complexes with proteins, via enhanced hydrophobicity, and provide novel methods for identification of specific molecular events in complex solutions, via selective detection by (19)F NMR and the absence of native (19)F signals in biological contexts. However, the potential applications of (19)F NMR in probing biological processes are limited both by the strong propensities of most highly fluorinated amino acids for the extended conformation and by the relatively modest sensitivity of NMR spectroscopy, which typically constrains measurements to mid-micromolar concentrations...
February 15, 2017: Biochemistry
keyword
keyword
20161
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"