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https://www.readbyqxmd.com/read/27897327/high-performance-liquid-chromatography-evaluation-of-the-enantiomeric-purity-of-amino-acids-by-means-of-automated-precolumn-derivatization-with-ortho-phthalaldehyde-and-chiral-thiols
#1
Raphael Kühnreich, Ulrike Holzgrabe
The use of ortho-phthalaldehyde (OPA) for the derivatization of amino acids (AA) is well known. It enables the separation of the derivatives on common reversed phase columns and improves the sensitivity with fluorescence detection. With the use of a chiral thiol an indirect enantioseparation of chiral amines and AAs is feasible. The major drawback of the OPA-derivatization is the poor stability of the products. Here, a method with an in-needle derivatization procedure is optimized to facilitate a quantitative conversion of the AA with OPA and the chiral thiols N-acetyl-L-cysteine or N-isobutyryl-L-cysteine, followed by a subsequent analysis, eluding the stability issue...
December 2016: Chirality
https://www.readbyqxmd.com/read/27879283/infant-videofluoroscopic-swallow-study-testing-swallowing-interventions-and-future-acute-respiratory-illness
#2
Eric R Coon, Rajendu Srivastava, Gregory J Stoddard, Sheena Reilly, Christopher G Maloney, Susan L Bratton
OBJECTIVES: Tube feedings are commonly prescribed to infants with swallowing abnormalities detected by videofluoroscopic swallow study (VFSS), but there are no studies demonstrating efficacy of these interventions to reduce risk of acute respiratory illness (ARI). We sought to measure the association between swallowing interventions and future ARI, among VFSS-tested infants. METHODS: Retrospective cohort of all infants (<12 months) tested with VFSS at a children's hospital between January 1, 2010, and January 1, 2012...
December 2016: Hospital Pediatrics
https://www.readbyqxmd.com/read/27878110/discontinuation-of-antimicrobial-prophylaxis-ap-in-children-with-spina-bifida-a-case-series-analysis
#3
Kevin G Couloures, Michael Anderson, Michael Machiorlatti, Olivera Marsenic, Lawrence Opas
BACKGROUND: Spina bifida increases the risk for urinary tract infections (UTI). Antimicrobial prophylaxis (AP) reduces symptomatic UTI's but selects resistant organisms. Measures to ensure regular and complete emptying of the bladder combined with treatment of constipation reduce the risk for UTI. OBJECTIVES: Demonstrate that close adherence to a catheterization regimen in children with spina bifida (Selective Treatment - ST) reduces the need for antimicrobial prophylaxis...
September 2016: Nephro-urology Monthly
https://www.readbyqxmd.com/read/27871251/epidemiology-and-rapd-pcr-typing-of-thermophilic-campylobacters-from-children-under-five-years-and-chickens-in-morogoro-municipality-tanzania
#4
Idrissa S Chuma, Hezron E Nonga, Robinson H Mdegela, Rudovick R Kazwala
BACKGROUND: Campylobacter species are gram negative and flagellated bacteria under the genus Campylobacter, family Campylobacteriaceae. These pathogens cause zoonotic infections among human and animal populations. This study was undertaken between December 2006 and May 2007 to determine prevalence, risk factors and genetic diversity of thermophilic Campylobacter isolates from children less than 5 years and chickens in Morogoro Municipality, Tanzania. METHODS: The Skirrow's protocol was used for isolation and identification of Campylobacter from 268 human stool specimens and 419 chicken cloacal swabs...
November 21, 2016: BMC Infectious Diseases
https://www.readbyqxmd.com/read/27866765/safety-tolerability-and-immunogenicity-of-a-single-dose-4-antigen-or-3-antigen-staphylococcus-aureus-vaccine-in-healthy-older-adults-results-of-a-randomised-trial
#5
C Buddy Creech, Robert W Frenck, Eric A Sheldon, David J Seiden, Martin K Kankam, Edward T Zito, Douglas Girgenti, Joseph M Severs, Frederick W Immermann, Lisa K McNeil, David Cooper, Kathrin U Jansen, William Gruber, Joseph Eiden, Annaliesa S Anderson, James Baber
BACKGROUND: The decline in immune function with age is a challenge to vaccine development. Following an initial study in adults aged 18-64years, this study evaluated the safety and immunogenicity of Staphylococcus aureus (S. aureus) 4-antigen (SA4Ag) and 3-antigen (SA3Ag) vaccine in older adults. SA3Ag included capsular polysaccharide serotypes 5 and 8 (CP5 and CP8) conjugated to the nontoxic mutant form of diphtheria toxin (CRM197) and a recombinant version of clumping factor A (ClfA)...
November 17, 2016: Vaccine
https://www.readbyqxmd.com/read/27864433/effect-of-occupational-physical-activities-on-vertebral-dimensions-in-midlife-in-the-northern-finland-birth-cohort-1966
#6
Petteri Oura, Markus Paananen, Jaakko Niinimäki, Juha Auvinen, Leena Ala-Mursula, Juho-Antti Junno, Jaro Karppinen
OBJECTIVES: The vertebral cross-sectional area (CSA) is a major determinant of vertebral strength. Since leisure-time physical activity (LTPA) is known to affect vertebral CSA, we hypothesised that engagement in physical activity at work might have similar effects on vertebral size. We aimed to examine the association between various adulthood occupational physical activities (OPA) and vertebral CSA, and to evaluate the association between OPA intensity and vertebral CSA. METHODS: We used the prospective population-based Northern Finland Birth Cohort 1966...
November 18, 2016: Occupational and Environmental Medicine
https://www.readbyqxmd.com/read/27847709/intermittent-oroesophageal-tube-feeding-via-the-airway-in-patients-with-dysphagia
#7
Hyo Kyung Shin, Kyo In Koo, Chang Ho Hwang
OBJECTIVE: To investigate the feasibility of the use of the oropharyngeal airway (OPA) during intermittent oroesophageal tube (IOET) feeding. METHODS: Ten patients, who were evaluated using the videofluoroscopic swallowing study (VFSS), were enrolled. One patient withdrew from the study during the study period. Tube insertion time with and without OPA use was recorded in the same patients in a random order during the VFSS. Patients who could safely undergo IOET feeding were then randomly allocated to 2 groups (OPA and non-OPA)...
October 2016: Annals of Rehabilitation Medicine
https://www.readbyqxmd.com/read/27847176/association-of-serum-bactericidal-antibody-and-opsonic-antibody-levels-after-neisseria-meningitidis-serogroup-c-conjugate-vaccine-in-brazilian-children-and-adolescents-infected-or-not-infected-with-hiv
#8
Wânia F Pereira-Manfro, Raquel M Alvino, Aline C Cruz, Giselle P Silva, Raquel B N Castro, Bianca Ferreira, Daniella M Barreto, Ana Cristina C Frota, Cristina B Hofer, Lucimar G Milagres
Neisseria meningitidis serogroup C (MenC) is the main causative agent of meningitis in Brazil. HIV infection affects the quality of the immune system. HIV(+) children have an increased risk of infection to encapsulated bacteria such as N. meningitidis. We evaluated the opsonic antibody (OPA) levels and its correlation with serum bactericidal antibody (SBA) levels induced by one and two doses of a MenC conjugate vaccine in children and adolescents HIV(+) and HIV-exposed but uninfected children (HEU) group. Overall the data show the importance of two doses of vaccine for HIV(+) individuals...
December 7, 2016: Vaccine
https://www.readbyqxmd.com/read/27828439/high-energy-two-cycle-pulses-at-3-2-%C3%AE-m-by-a-broadband-pumped-dual-chirped-optical-parametric-amplification
#9
Yanchun Yin, Jie Li, Xiaoming Ren, Yang Wang, Andrew Chew, Zenghu Chang
A design for efficient generation of mid-infrared pulses at 3.2 μm is presented, which is based on numerical simulations of the broadband-pumped dual-chirped optical parametric amplification (DC-OPA) in LiNbO<sub>3</sub> doped with 5 mol.% MgO (MgO:LiNbO<sub>3</sub>). The broadband seed can be generated by difference frequency generation in KTA using spectrally-broadened Ti:Sapphire lasers. The broad DC-OPA phase-matching bandwidth-spanning from 2.4 μm to 4.0 μm-is achieved by chirping both the broadband Ti:Sapphire pump pulses and the seed pulses in such a way that the individual temporal slice of pump spectrum is able to phase match that of seed spectrum...
October 31, 2016: Optics Express
https://www.readbyqxmd.com/read/27828229/theoretical-investigations-of-broadband-mid-infrared-optical-parametric-amplification-based-on-a-la-sub-3-sub-ga-sub-5-5-sub-nb-sub-0-5-sub-o-sub-14-sub-crystal
#10
Jingui Ma, Jing Wang, Dongxia Hu, Peng Yuan, Guoqiang Xie, Heyuan Zhu, Haohai Yu, Huaijin Zhang, Jiyang Wang, Liejia Qian
Recent progress in strong-field physics has stimulated the quest for intense mid-infrared ultrashort light sources. Optical parametric amplification (OPA) is one promising method to build up such sources, however, its development significantly relies on the availability of suitable nonlinear crystals. Here, we introduce a positive uniaxial crystal La<sub>3</sub>Ga<sub>5.5</sub>Nb<sub>0.5</sub>O<sub>14</sub> (LGN), which exhibits a favorable set of optical properties for the application in a mid-IR OPA...
October 17, 2016: Optics Express
https://www.readbyqxmd.com/read/27807421/cancer-and-chemotherapy-contribute-to-muscle-loss-by-activating-common-signaling-pathways
#11
Rafael Barreto, Giorgia Mandili, Frank A Witzmann, Francesco Novelli, Teresa A Zimmers, Andrea Bonetto
Cachexia represents one of the primary complications of colorectal cancer due to its effects on depletion of muscle and fat. Evidence suggests that chemotherapeutic regimens, such as Folfiri, contribute to cachexia-related symptoms. The purpose of the present study was to investigate the cachexia signature in different conditions associated with severe muscle wasting, namely Colon-26 (C26) and Folfiri-associated cachexia. Using a quantitative LC-MS/MS approach, we identified significant changes in 386 proteins in the quadriceps muscle of Folfiri-treated mice, and 269 proteins differentially expressed in the C26 hosts (p < 0...
2016: Frontiers in Physiology
https://www.readbyqxmd.com/read/27806200/an-investigation-into-biological-environments-through-non-linear-optics-a-multiscale-study-of-laurdan-derivatives
#12
Silvio Osella, Natarajan Arul Murugan, Naresh Kumar Jena, Stefan Knippenberg
The fluorescent marker Laurdan and its new derivative, C-Laurdan, have been investigated by means of theoretical calculations in a DOPC lipid bilayer membrane at room temperature and a comparison is made with results from fluorescence experiments. Experimentally, the latter probe is known to have a higher sensitivity to the membrane polarity at the lipid head-group region and has higher water solubility. Results from Molecular Dynamics (MD) simulations show that C-Laurdan is oriented with the carboxyl group towards the head of the membrane, with an angle of 50° between the molecular backbone and the normal to the bilayer, in contrast to the orientation of the Laurdan head-group whose carbonyl group is oriented towards the polar regions of the membrane and which describes an angle of ca...
November 2, 2016: Journal of Chemical Theory and Computation
https://www.readbyqxmd.com/read/27798013/safety-and-immunogenicity-of-a-new-13-valent-pneumococcal-conjugate-vaccine-versus-a-licensed-7-valent-pneumococcal-conjugate-vaccine-a-study-protocol-of-a-randomised-non-inferiority-trial-in-china
#13
Jing Jing Chen, Lin Yuan, Zhen Huang, Nian Min Shi, Yu Liang Zhao, Sheng Li Xia, Guo Hua Li, Rong Cheng Li, Yan Ping Li, Shu Yuan Yang, Jie Lai Xia
INTRODUCTION: The invasive pneumococcal diseases (IPDs) caused by Streptococcus pneumoniae pose an enormous threat to children under 5 years of age. However, routine use of pneumococcal conjugate vaccines could aid in reducing the incidence of IPDs. The purpose of this clinical trial is to assess the non-inferiority of the investigational 13-valent pneumococcal conjugate vaccine (PCV13) to the currently licensed 7-valent pneumococcal conjugate vaccine (PCV7). METHODS AND ANALYSIS: 1040 infants will receive a three-dose series of either PCV13 or PCV7 at ages 3, 4 and 5 months, respectively, and a booster dose at 12-15 months...
October 19, 2016: BMJ Open
https://www.readbyqxmd.com/read/27792338/base-promoted-4-1-3-1-1-bicyclization-of-for-accessing-functionalized-indeno-1-2-c-furans
#14
Wen-Juan Hao, Qian Gao, Bo Jiang, Feng Liu, Shu-Liang Wang, Shu-Jiang Tu, Guigen Li
A novel three-component bicyclization strategy for the metal-free synthesis of densely functionalized indeno[1,2-c]furans with generally good yields has been established from readily accessible o-phthalaldehydes (OPA), isocyanides and alpha-diazoketones. The reaction pathway involves aldol-type addition, 1,2-hydride shift, 5-exo-trig cyclization, and 1,4-addition as well as oxo-5-exo-dig cyclization sequence, resulting in continuous multiple bond-forming events including C-C and C-O bonds to rapidly build up functional oxo-heterocycle...
October 28, 2016: Journal of Organic Chemistry
https://www.readbyqxmd.com/read/27780630/effect-of-tdap-when-administered-before-with-or-after-the-13-valent-pneumococcal-conjugate-vaccine-coadministered-with-the-quadrivalent-meningococcal-conjugate-vaccine-in-adults-a-randomised-controlled-trial
#15
M Tashani, M Alfelali, O Barasheed, A S Alqahtani, L Heron, M Wong, H Rashid, R Booy
Sequential or co-administration of vaccines has potential to alter the immune response to any of the antigens. Existing literature suggests that prior immunisation of tetanus/diphtheria-containing vaccines can either enhance or suppress immune response to conjugate pneumococcal or meningococcal vaccines. We examined this interaction among adult Australian travellers before attending the Hajj pilgrimage 2014. We also investigated tolerability of these vaccines separately and concomitantly. We randomly assigned each participant to one of three vaccination schedules...
October 22, 2016: Vaccine
https://www.readbyqxmd.com/read/27774124/varying-chirality-across-nicotinic-acetylcholine-receptor-subtypes-selective-binding-of-quinuclidine-triazole-compounds
#16
Jiradanai Sarasamkan, Matthias Scheunemann, Nattayaporn Apaijai, Siripong Palee, Warisara Parichatikanond, Kuntarat Arunrungvichian, Steffen Fischer, Siriporn Chattipakorn, Winnie Deuther-Conrad, Gerrit Schüürmann, Peter Brust, Opa Vajragupta
The novel quinuclidine anti-1,2,3-triazole derivatives T1-T6 were designed based on the structure of QND8. The binding studies revealed that the stereochemistry at the C3 position of the quinuclidine scaffold plays an important role in the nAChR subtype selectivity. Whereas the (R)-enantiomers are selective to α7 over α4β2 (by factors of 44-225) and to a smaller degree over α3β4 (3-33), their (S)-counterparts prefer α3β4 over α4β2 (62-237) as well as over α7 (5-294). The (R)-derivatives were highly selective to α7 over α3β4 subtypes compared to (RS)- and (R)-QND8...
October 13, 2016: ACS Medicinal Chemistry Letters
https://www.readbyqxmd.com/read/27763507/transmit-power-allocation-for-physical-layer-security-in-cooperative-multi-hop-full-duplex-relay-networks
#17
Jong-Ho Lee, Illsoo Sohn, Yong-Hwa Kim
In this paper, we consider a transmit power allocation problem for secure transmission in multi-hop decode-and-forward (DF) full-duplex relay (FDR) networks, where multiple FDRs are located at each hop and perform cooperative beamforming to null out the signal at multiple eavesdroppers. For a perfect self-interference cancellation (PSIC) case, where the self-interference signal at each FDR is completely canceled, we derive an optimal power allocation (OPA) strategy using the Karush-Kuhn-Tucker (KKT) conditions to maximize the achievable secrecy rate under an overall transmit power constraint...
October 17, 2016: Sensors
https://www.readbyqxmd.com/read/27757056/epiglottis-cross-sectional-area-and-oropharyngeal-airway-length-in-male-and-female-obstructive-sleep-apnea-patients
#18
Melinda A Ma, Rajesh Kumar, Paul M Macey, Frisca L Yan-Go, Ronald M Harper
INTRODUCTION: Obstructive sleep apnea (OSA) is a male-predominant condition, characterized by repeated upper-airway collapse with continued diaphragmatic efforts during sleep, and is accompanied by severe physiological consequences. Multiple morphological aspects, including epiglottis cross-sectional area (CSA) and oropharyngeal airway length (OPAL), can contribute to airway collapsibility in the condition. This study focused on the effects of OSA severity, sex, and race on OPA dimensions...
2016: Nature and Science of Sleep
https://www.readbyqxmd.com/read/27747885/rapid-labelling-of-amino-neurotransmitters-with-a-fluorescent-thiol-in-the-presence-of-o-phthalaldehyde
#19
Naveen Maddukuri, Qiyang Zhang, Ning Zhang, Maojun Gong
Laser-induced fluorescence (LIF) detection often requires labelling of analytes with fluorophores; and fast fluorescent derivatization is valuable for high-throughput analysis with flow-gated capillary electrophoresis (CE). Here, we report a fast fluorescein-labelling scheme for amino neurotransmitters, which were then rapidly separated and detected in flow-gated CE. This scheme was based on the reaction between primary amines and o-phthalaldehyde (OPA) in the presence of a fluorescent thiol, 2-[(5-fluoresceinyl)aminocarbonyl]ethyl mercaptan (FACE-SH)...
October 17, 2016: Electrophoresis
https://www.readbyqxmd.com/read/27746550/a-prospective-randomized-control-study-comparing-classic-laryngeal-mask-airway-with-guedel-s-airway-for-tracheal-tube-exchange-and-smooth-extubation
#20
Shruti Jain, Nazia Nazir, Rashid M Khan, Syed M Ahmed
INTRODUCTION: Extubation in deep plane of anesthesia followed by Guedel's oropharyngeal airway (OPA™) insertion is a routine method to avoid hemodynamic changes associated with tracheal extubation. Exchange of endotracheal tube (ETT) with Classic laryngeal mask airway (LMA™) prior to emergence from anesthesia also serves similar purpose. We had compared the hemodynamic changes involved during this ETT/LMA™ and ETT/OPA™ exchange technique. MATERIAL AND METHODS: This was a randomized prospective study on ASA I and 2 patients undergoing elective surgery under general anesthesia...
September 2016: Anesthesia, Essays and Researches
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