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https://www.readbyqxmd.com/read/28919848/hidden-hearing-loss-no-effect-of-common-recreational-noise-exposure-on-cochlear-nerve-response-amplitude-in-humans
#1
Sarah K Grinn, Kathryn B Wiseman, Jason A Baker, Colleen G Le Prell
This study tested hypothesized relationships between noise exposure and auditory deficits. Both retrospective assessment of potential associations between noise exposure history and performance on an audiologic test battery and prospective assessment of potential changes in performance after new recreational noise exposure were completed. Methods: 32 participants (13M, 19F) with normal hearing (25-dB HL or better, 0.25-8 kHz) were asked to participate in 3 pre- and post-exposure sessions including: otoscopy, tympanometry, distortion product otoacoustic emissions (DPOAEs) (f2 frequencies 1-8 kHz), pure-tone audiometry (0...
2017: Frontiers in Neuroscience
https://www.readbyqxmd.com/read/28903506/a-population-based-assessment-of-the-impact-of-7-and-13-valent-pneumococcal-conjugate-vaccines-on-macrolide-resistant-invasive-pneumococcal-disease-emergence-and-decline-of-streptococcus-pneumoniae-serotype-19a-cc320-with-dual-macrolide-resistance-mechanisms
#2
Max R Schroeder, Scott T Chancey, Stephanie Thomas, Wan-Hsuan Kuo, Sarah W Satola, Monica M Farley, David S Stephens
Background: Macrolide efflux encoded by mef(E)/mel and ribosomal methylation encoded by erm(B) confer most macrolide resistance in Streptococcus pneumoniae. Introduction of the heptavalent pneumococcal conjugate vaccine (PCV7) in 2000 reduced macrolide-resistant invasive pneumococcal disease (MR-IPD) due to PCV7 serotypes (6B, 9V, 14, 19F, and 23F). Methods: In this study, the impact of PCV7 and PCV13 on MR-IPD was prospectively assessed. A 20-year study of IPD performed in metropolitan Atlanta, Georgia, using active, population-based surveillance formed the basis for this study...
September 15, 2017: Clinical Infectious Diseases: An Official Publication of the Infectious Diseases Society of America
https://www.readbyqxmd.com/read/28890403/sex-differences-in-respiratory-muscle-activation-patterns-during-high-intensity-exercise-in-healthy-humans
#3
Reid A Mitchell, Michele R Schaeffer, Andrew H Ramsook, Sabrina S Wilkie, Jordan A Guenette
Although women experience greater ventilatory constraints and have a higher work of breathing during exercise, they are less susceptible to diaphragm fatigue compared to men. The mechanisms for diaphragmatic fatigue resistance in women is unknown but may be related to sex differences in respiratory muscle recruitment. Accordingly, the purpose of this study was to determine if electromyography (EMG) of the diaphragm (EMGdi) and extra-diaphragmatic inspiratory muscles differ between sexes during exercise. Forty subjects (21M:19F) completed a constant load cycling test at 85% of maximum work rate until exhaustion, while instrumented with an oesophageal electrode catheter to measure EMGdi and surface electrodes to measure EMG of the sternocleidomastoid (EMGscm) and scalene (EMGsca) muscles...
September 7, 2017: Respiratory Physiology & Neurobiology
https://www.readbyqxmd.com/read/28875600/validation-of-the-world-health-organization-enzyme-linked-immunosorbent-assay-for-the-quantitation-of-immunoglobulin-g-serotype-specific-anti-pneumococcal-antibodies-in-human-serum
#4
Hyunju Lee, Soo Young Lim, Kyung Hyo Kim
The World Health Organization (WHO) enzyme-linked immunosorbent assay (ELISA) guideline is currently accepted as the gold standard for the evaluation of immunoglobulin G (IgG) antibodies specific to pneumococcal capsular polysaccharide. We conducted validation of the WHO ELISA for 7 pneumococcal serotypes (4, 6B, 9V, 14, 18C, 19F, and 23F) by evaluating its specificity, precision (reproducibility and intermediate precision), accuracy, spiking recovery test, lower limit of quantification (LLOQ), and stability at the Ewha Center for Vaccine Evaluation and Study, Seoul, Korea...
October 2017: Journal of Korean Medical Science
https://www.readbyqxmd.com/read/28872126/application-and-methodology-of-the-non-destructive-19f-time-domain-nmr-technique-to-measure-the-content-in-fluorine-containing-drug-products
#5
Maria Victoria Silva Elipe, Lan Li, Karthik Nagapudi, Alan M Kook, Carlos Cobas, Isaac Iglesias, Chen Peng
Here, we describe a protocol developed by our group that uses low-field fluorine-19 ((19)F) time-domain (TD) nuclear magnetic resonance (NMR) to measure the average content of fluorinated drugs in their formulated drug product forms: tablets or capsules. This method is specific to fluorinated drugs because it detects only the content of fluorine, avoiding interference from the excipients that lack fluorine. The advantages of measuring the active content of fluorinated drugs using low-field (19)F TD-NMR versus high-field (19)F solid-state (SS) NMR are the simplicity of the method; the low cost; and the non-destructive nature of the technique, with all samples recoverable in intact forms (e...
August 22, 2017: Journal of Visualized Experiments: JoVE
https://www.readbyqxmd.com/read/28867594/serotype-and-mlst-based-inference-of-population-structure-of-clinical-streptococcus-pneumoniae-from-invasive-and-noninvasive-pneumococcal-disease
#6
Haijian Zhou, Jiayin Guo, Tian Qin, Hongyu Ren, Yang Xu, Chuanqing Wang, Xuebin Xu
Streptococcus pneumoniae is an important human pathogen causing various diseases. In this study, S. pneumoniae from invasive (IPD) and noninvasive pneumococcal disease (NIPD) were studied by serotype and multilocus sequence typing (MLST) for population structure characteristics. A total of 169 clinical S. pneumoniae, containing 63 IPD and 106 NIPD strains, were analyzed. 19F, 19A, 6A, 6B, 1, 14 and 23F were the dominant serotypes in both IPD and NIPD strains. By MLST, 169 strains were divided into 85 sequence types (STs) with an index of discrimination (IOD) value of 0...
September 1, 2017: Infection, Genetics and Evolution
https://www.readbyqxmd.com/read/28854845/role-of-streptococcus-pneumoniae-infection-in-chronic-obstructive-pulmonary-disease-patients-in-italy
#7
Marco Mantero, Stefano Aliberti, Chiara Azzari, Maria Moriondo, Francesco Nieddu, Francesco Blasi, Marta Di Pasquale
BACKGROUND: The aim of this study was to determine the incidence of exacerbations due to Streptococcus pneumoniae in chronic obstructive pulmonary disease (COPD) patients during stable state. METHODS: We conducted a prospective, observational, cohort study including stable COPD patients, who were evaluated at least every 4 months over a 24-month period at the Respiratory Unit of the IRCCS Policlinico Hospital in Milan, Italy, from 2012 to 2015. Sputum samples were collected at enrollment during stable state to evaluate the frequency of S...
August 1, 2017: Therapeutic Advances in Respiratory Disease
https://www.readbyqxmd.com/read/28846825/use-of-fluorine-pseudocontact-shifts-to-characterize-the-protein-ligand-interaction-mode-in-the-limit-of-nmr-intermediate-exchange
#8
Jia Gao, E Liang, Rongsheng Ma, Fudong Li, Yiyang Liu, Jiuyang Liu, Ling Jiang, Conggang Li, Haiming Dai, Jihui Wu, Xuncheng Su, Wei He, Ke Ruan
The characterization of protein-ligand interaction modes becomes recalcitrant in the NMR intermediate exchange regime as the interface resonances are broadened beyond detection. Here, we determined the 19F low-populated bound-state pseudocontact shifts (PCSs) of mono- and di-fluorinated inhibitors of the BRM bromodomain using a highly-skewed protein/ligand ratio. The bound-state 19F PCSs were retrieved from 19F chemical exchange saturation transfer (CEST) in the presence of the lanthanide-labeled protein, which was termed the 19F PCS-CEST approach...
August 28, 2017: Angewandte Chemie
https://www.readbyqxmd.com/read/28841854/distribution-of-streptococcus-pneumoniae-serotypes-in-the-northeast-macro-region-of-s%C3%A3-o-paulo-state-brazil-after-the-introduction-of-conjugate-vaccine
#9
Marta Inês Cazentini Medeiros, Samanta Cristine Grassi Almeida, Maria Luiza Leopoldo Silva Guerra, Paulo da Silva, Ana Maria Machado Carneiro, Denise de Andrade
BACKGROUND: Infections caused by Streptococcus pneumoniae (Spn) still challenge health systems around the world, even with advances in vaccination programs. The present study evaluated the frequency of various Spn serotypes isolated in Regional Health Care Network 13 (RRAS 13), which includes the regional health departments (RHDs) of Araraquara, Barretos, Franca and Ribeirão Preto, especially after the introduction of 10-valent pneumococcal conjugate vaccine (PCV10) in 2010. METHODS: The analyzed Spn strains were isolated from patients with invasive pneumococcal diseases (IPDs) and then sent to Adolfo Lutz Institute (ALI) for further confirmative identification tests during the period from 1998 to 2013...
August 25, 2017: BMC Infectious Diseases
https://www.readbyqxmd.com/read/28820590/conformational-heterogeneity-in-a-fully-complementary-dna-three-way-junction-with-a-gc-rich-branchpoint
#10
Anita Toulmin, Laura E Baltierra-Jasso, Michael J Morten, Tara Sabir, Peter McGlynn, Gunnar F Schröder, Brian O Smith, Steven W Magennis
DNA three-way junctions (3WJs) are branched structures that serve as important biological intermediates and as components in DNA nanostructures. We recently derived the global structure of a fully complementary 3WJ and found that it contained unpaired bases at the branchpoint, which is consistent with previous observations of branch flexibility and branchpoint reactivity. By combining high-resolution single-molecule Förster resonance energy transfer, molecular modeling, time-resolved ensemble fluorescence spectroscopy, and the first (19)F nuclear magnetic resonance observations of fully complementary 3WJs, we now show that the 3WJ structure can adopt multiple distinct conformations depending upon the sequence at the branchpoint...
September 1, 2017: Biochemistry
https://www.readbyqxmd.com/read/28818574/antimicrobial-resistance-determinants-and-susceptibility-profiles-of-pneumococcal-isolates-recovered-in-trinidad-and-tobago
#11
Paulina A Hawkins, Patrick E Akpaka, Michele Nurse-Lucas, Rebecca Gladstone, Stephen D Bentley, Robert F Breiman, Lesley McGee, William H Swanston
INTRODUCTION: In Latin America and the Caribbean, pneumococcal infections were estimated to account for 12,000-18,000 deaths, 327,000 cases of pneumonia, 4,000 cases of meningitis and 1,229 cases of sepsis each year in children under five years old. Resistance of pneumococci to antimicrobial agents has evolved into a worldwide health problem in the last few decades. OBJECTIVE: The aim of this study was to determine the antimicrobial susceptibility profiles of 98 pneumococcal isolates collected in Trinidad and Tobago and associated genetic determinants...
August 14, 2017: Journal of Global Antimicrobial Resistance
https://www.readbyqxmd.com/read/28817670/synthesis-radiosynthesis-and-in-vitro-evaluation-of-18f-bodipy-c16-triglyceride-as-a-dual-modal-imaging-agent-for-brown-adipose-tissue
#12
Andreas Paulus, Marco Maenen, Natascha Drude, Emmani B M Nascimento, Wouter D van Marken Lichtenbelt, Felix M Mottaghy, Matthias Bauwens
BACKGROUND: Brown adipose tissue research is in the focus in the field of endocrinology. We designed a dual-modal fluorescent/PET fatty acid based tracer on commercially available Bodipy-C16, which can be synthesized to its corresponding triglyceride and which combines the benefits of fluorescent and PET imaging. METHODS: Bodipy-C16 was coupled to 1,3-diolein resulting in Bodipy-triglyceride. Bodipy-C16 and Bodipy-triglyceride compounds were radiolabeled with 18F using an 18F/19F exchange reaction to yield a dual-modal imaging molecule...
2017: PloS One
https://www.readbyqxmd.com/read/28783319/sharper-reaction-monitoring-generation-of-a-narrow-linewidth-nmr-singlet-without-x-pulses-in-an-inhomogeneous-magnetic-field
#13
Ariana B Jones, Guy C Lloyd-Jones, Dušan Uhrín
We report a new pure-shift method, termed SHARPER (Sensitive, Homogeneous, And Resolved PEaks in Real time) designed for the analysis of reactions and equilibria by NMR. By focusing on a single selected signal, SHARPER removes all heteronuclear couplings of a selected nucleus without the need to pulse on X channels, thus overcoming hardware limitations of conventional spectrometers. A more versatile decoupling scheme, termed sel-SHARPER, removes all heteronuclear and homonuclear couplings of the selected signal...
August 25, 2017: Analytical Chemistry
https://www.readbyqxmd.com/read/28780980/impact-of-the-hajj-on-pneumococcal-carriage-and-the-effect-of-various-pneumococcal-vaccines
#14
REVIEW
Sophie Edouard, Jaffar A Al-Tawfiq, Ziad A Memish, Saber Yezli, Philippe Gautret
BACKGROUND: The Islamic Hajj pilgrimage is the largest annual mass gathering in the world. The overcrowding of people promotes the acquisition, spread and transmission of respiratory pathogens, including Streptococcus pneumoniae. It is estimated that about 33% of pilgrims are at risk of invasive pneumococcal disease. METHODS: We conducted a methodological review according to the Preferred Reporting Items for Systematic Reviews and meta-Analysis guidelines. The objective was to summarize the available data regarding the prevalence of pneumococcal carriage among Hajj pilgrims and about carriage acquisition and circulation of S...
August 3, 2017: Vaccine
https://www.readbyqxmd.com/read/28777565/synthesis-and-characterization-of-pegylated-and-fluorinated-chitosans-application-to-the-synthesis-of-targeted-nanoparticles-for-drug-delivery
#15
Yamina Belabassi, Juliette Moreau, Virginia Gheran, Celine Henoumont, Anthony Robert, Maité Callewaert, Guillaume Rigaux, Cyril Cadiou, Luce Vander Elst, Sophie Laurent, Robert N Muller, Anca Dinischiotu, Sorina N Voicu, Françoise Chuburu
To synthesize chitosan nanoparticles (CS NPs), ionic gelation is a very attractive method. It relies on the spontaneous supramolecular assembly of cationic CS with anionic compounds, which leads to nanohydrogels. To extend ionic gelation to functionalized CS, the assessment of CS degree of substitution (DSCS) is a key step. In this paper, we have developed a hyphenated strategy for functionalized CS characterization, based upon (1)H, DOSY and, when relevant, 1D diffusion-filtered (19)F NMR spectroscopies. For that, we have synthesized two series of water-soluble CS via amidation of CS amino groups with mPEG2000-COOH or fluorinated synthons (TFB-COOH)...
August 24, 2017: Biomacromolecules
https://www.readbyqxmd.com/read/28777560/a-critical-cross-catalytic-relationship-determines-the-outcome-of-competition-in-a-replicator-network
#16
Tamara Kosikova, Douglas Philp
A network of two synthetic replicators exhibits a critical unidirectional cross-catalytic relationship that directs competing replication processes. In this network, nitrone N bearing a 6-methylamidopyridine recognition site can participate in 1,3-dipolar cycloaddition reactions with two maleimides that differ in the relative position of their carboxylic acid recognition site: either para (M(p)) or meta (M(m)) relative to the maleimide ring. These cycloaddition reactions create replicators trans-T(p) and trans-T(m)...
August 29, 2017: Journal of the American Chemical Society
https://www.readbyqxmd.com/read/28777495/increased-conformational-flexibility-of-a-macrocycle-receptor-complex-contributes-to-reduced-dissociation-rates
#17
Adrian Glas, Eike-Christian Wamhoff, Dennis M Krüger, Christoph Rademacher, Tom N Grossmann
Constraining a peptide in its bioactive conformation via macrocyclization represents a powerful strategy to design modulators of challenging biomolecular targets. This holds particularly true for the development of inhibitors of protein-protein interactions which often involve interfaces lacking defined binding pockets. Such flat surfaces are demanding targets for traditional small molecules rendering macrocyclic peptides promising scaffolds for novel therapeutics. However, the contribution of peptide dynamics to binding kinetics is barely understood which impedes the design process...
August 4, 2017: Chemistry: a European Journal
https://www.readbyqxmd.com/read/28776972/controlled-zn-2-triggered-drug-release-by-preferred-coordination-of-open-active-sites-within-functionalization-indium-metal-organic-frameworks
#18
Xi Du, Ruiqing Fan, Liangsheng Qiang, Kai Xing, Haoxin Ye, Xinya Ran, Yang Song, Ping Wang, Yulin Yang
Drug delivery in target regions could make extraordinary progress in chemoselective therapies. A novel preferred coordination (PC) strategy referring to proactive interacting with open active sites to replace previous occupation by ion-exchange for controlling release of drug molecules is well-constructed. Two topological types of MOF-In1 (Schläfli symbol: (4,8)-connected of (4(10)·6(15)·8(3))(4(5)·6)2) and MOF-In2 (Schläfli symbol: (4,4)-connected of (6(6))) show the specific way. Increasing node connectivity as well as the trapping of guest OH(-) anions, 5-fluorouracil (5-FU) is preferentially captured into the MOF-In1, which exhibits an outstanding loading capacity around 34...
August 30, 2017: ACS Applied Materials & Interfaces
https://www.readbyqxmd.com/read/28758387/characterization-of-heme-orientational-disorder-in-a-myoglobin-reconstituted-with-a-trifluoromethyl-group-substituted-heme-cofactor
#19
Yuki Kanai, Ayaka Harada, Tomokazu Shibata, Ryu Nishimura, Kosuke Namiki, Miho Watanabe, Shunpei Nakamura, Fumiaki Yumoto, Toshiya Senda, Akihiro Suzuki, Saburo Neya, Yasuhiko Yamamoto
The orientation of a CF3-substituted heme in sperm whale myoglobin and L29F, H64L, L29F/H64Q, and H64Q variant proteins has been investigated using (19)F NMR spectroscopy to elucidate structural factors responsible for the thermodynamic stability of the heme orientational disorder, i.e., the presence of two heme orientations differing by a 180° rotation about the 5-15 meso axis, with respect to the protein moiety. Crystal structure of the met-aquo form of the wild-type myoglobin reconstituted with 13,17-bis(2-carboxylatoethyl)-3,8-diethyl-2,12,18-trimethyl-7-trifluoromethylporphyrinatoiron(III), determined at resolution of 1...
August 29, 2017: Biochemistry
https://www.readbyqxmd.com/read/28756964/key-features-of-invasive-pneumococcal-isolates-recovered-in-lima-peru-determined-through-whole-genome-sequencing
#20
Paulina Hawkins, Erik Mercado, Sopio Chochua, Maria E Castillo, Isabel Reyes, Eduardo Chaparro, Rebecca Gladstone, Stephen D Bentley, Robert F Breiman, Benjamin J Metcalf, Bernard Beall, Theresa J Ochoa, Lesley McGee
Before PCV7 introduction, invasive pneumococcal disease (IPD) was responsible for approximately 12,000-18,000 deaths annually among children <5years in Latin America. In Peru, PCV7 was introduced in 2009. We used whole genome sequencing to deduce key features of invasive strains collected in Lima, Peru from 2006 to 2011. We sequenced 212 IPD isolates from 16 hospitals in Lima pre (2006-2009; n=133) and post (2010-2011; n=79) PCV7 introduction; 130 (61.3%) isolates were from children≤5years old. CDC's Streptococcus lab bioinformatics pipeline revealed serotypes, sequence types (STs), pilus genes, PBP types and other resistance determinants...
July 22, 2017: International Journal of Medical Microbiology: IJMM
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