bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ionic determinants of exhaled breath condensate pH before and after exercise in adolescent athletes
Authors: Greenwald Roby , Ferdinands Jill M. , Teague W. Gerald 
Published: July 2009

AbstractBackgroundThe pH of exhaled breath condensate (EBC) of adolescent athletes engaged in vigorous physical activity is low compared to healthy controls; however, the ionic determinants of EBC pH and the acute effects of exercise on those determinants have not been definitively established.ObjectivesThis study had two purposes: (1) to identify the ionic composition of EBC before and after exercise, and (2) to examine the effects of sample deaeration on EBC pH and composition.MethodsEBC ionic composition was determined by ion chromatography and correlated with pH measured before and after deaeration. Bicarbonate concentration was calculated from the ion balance of other measured species and pH.ResultsEBC pH displayed a bimodal distribution, included values lower than expected for healthy individuals, and was correlated exclusively with volatile species, namely ammonia (mean concentration = 215 µM) and acetic (31.7 µM) and propionic acids (10.0 µM). Following exercise, raw EBC pH and ammonia concentration increased while propionic acid concentration fell. Following deaeration, EBC pH increased by one unit on average; however, the pH of samples with unusually low pH did not change significantly, and the concentrations of several ionic species were altered in a manner that cannot be explained in terms of volatility.ConclusionsWe conclude that in healthy adolescents, exercise results in an acute increase in raw EBC pH in association with an increase in ammonium and a decrease in propionate concentration. Since exercise increases systemic ammonia and urea (which is hydrolyzed by oral bacteria to form ammonia), we propose that the likely source of these changes is gas‐phase diffusion from epithelial and oral surface liquids and to a lesser extent, from pulmonary circulation. Pediatr Pulmonol. 2009; 44:768–777. © 2009 Wiley‐Liss, Inc.
The effects of racemic albuterol versus levalbuterol in very low birth weight infants
Authors: Mhanna Maroun J. , Patel Jigisha S. , Patel Swati , Cohn Robert 
Published: July 2009

AbstractBronchodilators have been used in premature infants. Levalbuterol (LEV) an R‐isomer of Albuterol has fewer hemodynamic side effects than Racemic Albuterol (RAC) in adults and children. In a retrospective study we sought to investigate the effects of LEV (0.31 mg) versus RAC (1.25 mg) in very low‐birth weight infants (VLBW) who were treated with a beta‐2 agonist for ≥2 weeks. Medical records (between January 2001 and December 2006) were reviewed for patients' demographics, medications use, hemodynamic and respiratory parameters, hypokalemia and hyperglycemia. Among 811 VLBW infants who were admitted to our NICU, 16 infants received RAC and 31 infants received LEV for ≥2 weeks. Infants who received RAC were younger, smaller, and received less Ipratropium Bromide (IB) than infants who received LEV [26.1 ± 1.2 weeks vs. 28.1 ± 3.7 weeks (P = 0.01), 817 ± 211 g vs. 1,127 ± 589 g (P = 0.01) and 2/16 (12%) vs. 15/31 (48%; P = 0.01); respectively]. In infants treated exclusively with RAC or LEV without IB, mean arterial blood pressures were lower in the RAC (n = 14) than the LEV group (n = 16, P = 0.05 by general linear model with repeated measures); however there were no differences in daily heart rates, oxygen supplementations, oxygen saturations, or respiratory rates. Also there were no differences between the two groups in hypokalemia or hyperglycemia. We conclude that LEV at a dose of 0.31 mg might have an indication in VLBW infants who are at risk for hemodynamic instability. Pediatr Pulmonol. 2009; 44:778–783. © 2009 Wiley‐Liss, Inc.
Influence of ventilatory settings on exhaled nitric oxide during high frequency oscillatory ventilation
Authors: Yuh Yeong‐Seng , Hua Yi‐Ming 
Published: July 2009

AbstractNitric oxide (NO), which is produced in the lower airways, diffuses from cells into the air space and can be measured in exhaled air. The influence of high frequency oscillatory ventilation on the production of exhaled NO (eNO) has not been thoroughly studied. The objectives of this study are to establish an animal model for evaluation of lower airway NO and to evaluate settings in terms of frequency, mean airway pressure (MAP), amplitude pressure (amplitude), and inspiratory time ratio (tI/tE) during high frequency oscillatory ventilation on the production of eNO. An observational animal study was performed on 12 female New Zealand White rabbits, which were anesthetized, tracheotomized and ventilated using a SensorMedics 3100A HFOV ventilator (SM3100A). The concentration of NO in exhaled gas was measured by chemiluminescence continuously from the nose and the side hole of the adaptor of endotracheal tube. The individual effects of the respiratory settings were evaluated. The results were analyzed by paired t‐test or by the generalized estimating equation method. We found that the lower airway was the main source of the eNO, that amplitude, MAP, and tI/tE were positively correlated with the level of eNO and that frequency was negatively correlated with the level of eNO. These findings fit the stretch theory for the production of endogenous NO. Monitoring of eNO during HFOV may provide insights into lung mechanics and ventilation efficiency and be used in the future as a guide during clinical practice. Pediatr Pulmonol. 2009; 44:800–805. © 2009 Wiley‐Liss, Inc.
Design of potent 9‐mer antimicrobial peptide analogs of protaetiamycine and investigation of mechanism of antimicrobial action
Authors: Shin Soyoung , Kim Jin‐Kyoung , Lee Jee‐Young , Jung Ki‐Woong , Hwang Jae‐Sam , Lee Juneyoung , Lee Dong Gun , Kim Iksoo , Shin Song Yub , Kim Yangmee 
Published: July 2009

AbstractProtaetiamycine is an insect defensin, a naturally occurring 43‐amino‐acid‐residue antimicrobial peptide derived from the larvae of the beetle Protaetia brevitarsis. In a previous work that aimed at developing short antibiotic peptides, we designed 9‐mer peptide analogs of protaetiamycine. Among them, RLWLAIGRG‐NH2 showed good antifungal activity against Candida albicans. In this study, we designed four 9‐mer peptide analogs based on the sequence of RLWLAIGRG‐NH2, in which Gly or Ile was substituted with Arg, Lys, or Trp to optimize the balance between the hydrophobicity and cationicity of the peptides and to increase bacterial cell selectivity. We measured their toxicity to bacteria and mammalian cells as well as their ability to permeabilize model phospholipid membranes. Substitution of Arg for Gly9 at the C‐terminus (9Pbw1) resulted in two‐ to fourfold improvement in antibacterial activity. Further substitution of Gly7 with Lys (9Pbw2 and 9Pbw4) caused four‐ to eightfold improvement in the antibacterial activity without increase in cytotoxocity, while substitution of Gly7 with Trp (9Pbw3) increased cytotoxicity as well as antibacterial activity. The peptides 9Pbw2 and 9Pbw4 with the highest bacterial cell selectivity were not effective in depolarizing the membrane of Staphylococcus aureus cytoplasmic membranes and showed almost no leakage of a fluorescent dye entrapped within the vesicles. Gel‐retardation experiments indicated that 9Pbw2 and 9Pbw4 inhibited the migration of DNA at concentrations >20 µM. Three positively charged residues at the C‐terminus in 9Pbw2 and 9Pbw4 may facilitate effective penetration into the negatively charged phospholipid membrane of bacteria. The results obtained in this study suggest that the bactericidal action of our potent antibacterial peptides, namely 9Pbw2 and 9Pbw4, may be attributed to the inhibition of the functions of intracellular components after penetration of the bacterial cell membrane. Copyright © 2009 European Peptide Society and John Wiley & Sons, Ltd.
Critical percolation on random regular graphs
Authors: Nachmias Asaf , Peres Yuval 
Published: July 2009

AbstractThe behavior of the random graph G(n,p) around the critical probability pc = $ {1 \over n} $ is well understood. When p = (1 + O(n1/3))pc the components are roughly of size n2/3 and converge, when scaled by n−2/3, to excursion lengths of a Brownian motion with parabolic drift. In particular, in this regime, they are not concentrated. When p = (1 ‐ ϵ(n))pc with ϵ(n)n1/3 →∞ (the subcritical regime) the largest component is concentrated around 2ϵ−2 log(ϵ3n). When p = (1 + ϵ(n))pc with ϵ(n)n1/3 →∞ (the supercritical regime), the largest component is concentrated around 2ϵn and a duality principle holds: other component sizes are distributed as in the subcritical regime.Itai Benjamini asked whether the same phenomenon occurs in a random d‐regular graph. Some results in this direction were obtained by (Pittel, Ann probab 36 (2008) 1359–1389). In this work, we give a complete affirmative answer, showing that the same limiting behavior (with suitable d dependent factors in the non‐critical regimes) extends to random d‐regular graphs. © 2009 Wiley Periodicals, Inc. Random Struct. Alg., 2010
Estimating variance parameters from multivariate normal variables subject to limit of detection: MLE, REML, or Bayesian approaches?
Authors: Nie Lei , Chu Haitao , Feng Shibao 
Published: July 2009

AbstractLikelihood‐based approaches, which naturally incorporate left censoring due to limit of detection, are commonly utilized to analyze censored multivariate normal data. However, the maximum likelihood estimator (MLE) typically underestimates variance parameters. The restricted maximum likelihood estimator (REML), which corrects the underestimation of variance parameters, cannot be easily extended to analyze censored multivariate normal data. In the light of the connection between the REML and a Bayesian approach discovered in 1974 by Dr Harville, this paper describes a Bayesian approach to censored multivariate normal data. This Bayesian approach is justified through its link to the REML via Laplace's approximation and its performance is evaluated through a simulation study. We consider the Bayesian approach as a valuable alternative because it yields less biased variance parameter estimates than the MLE, and because a solid REML is technically difficult when data are left censored. Copyright © 2009 John Wiley & Sons, Ltd.
Mesoporous‐Silica‐Coated Up‐Conversion Fluorescent Nanoparticles for Photodynamic Therapy
Authors: Qian Hai Sheng , Guo Hui Chen , Ho Paul Chi‐Lui , Mahendran Ratha , Zhang Yong 
Published: July 2009

AbstractNear‐infrared (NIR)‐to‐visible up‐conversion fluorescent nanoparticles have potential to be used for photodynamic therapy (PDT) in deep tissue because NIR light can penetrate thick tissue due to weak absorption in the optical window. Here a uniform layer of mesoporous silica is coated onto NaYF4 up‐converting nanocrystals, with a large surface area of ≈770 m2 g−1 and an average pore size of 2 nm. A photosensitizer, zinc phthalocyanine, is incorporated into the mesoporous silica. Upon excitation by a NIR laser, the nanocrystals convert NIR light to visible light, which further activates the photosensitizer to release reactive singlet oxygen to kill cancer cells. The photosensitizer encapsulated in mesoporous silica is protected from degradation in the harsh biological environment. It is demonstrated that the photosensitizers loaded into the porous silica shell of the nanoparticles are not released out of the silica while they continuously produce singlet oxygen upon excitation by a NIR laser. The nanoparticles are reusable as the photosensitizers encapsulated in the silica are removed by soaking in ethanol.
Influence of Gluten and Gum Additives and Cryogenic Treatment on Some Properties and Morphology of Wheat Starch Complex Gels
Authors: Wasserman Luybov A. , Vasil'ev Viktor G. , Motyakin Michael V. , Blaszchak Wioletta , Fornal Jozef , Damshkaln Liliya G. , Lozinsky Vladimir I. , Yuryev Vladimir P. 
Published: July 2009

AbstractThe influence of gums (guar and xanthan) and gluten additives on the physicochemical properties and structural features of wheat starch gels (8%, w/w) subjected to cryogenic treatment at various temperatures (−9°C, −20°C, −40°C) was studied. Shear modulus and breaking stress of the gels were measured, the gels' morphology was studied with optical microscopy and the local mobility of water in the gels was determined with ESR. The total concentration of polysaccharide additives did not exceed 1% (w/w), and a 65:35 (w/w) mixture of guar and xanthan gums proved to be the optimal additive, which caused a noticeable increase in rigidity and strength of the resulting complex gels. Shear modulus and breaking stress of the gels decreased with lowering the temperature of the cryogenic treatment. The heterogeneous morphology of thin sections of the gel samples was revealed via optical microscopy. ESR studies showed that the local mobility of water was much lower in the gels than in pure water.
Evaluation ofN‐benzyl‐N‐[11C]methyl‐2‐ (7‐methyl‐8‐oxo‐2‐phenyl‐7,8‐dihydro‐9H‐purin‐9‐yl)acetamide ([11C]DAC) as a novel translocator protein (18 kDa) radioligand in kainic acid‐lesioned rat
Authors: Yanamoto Kazuhiko , Yamasaki Tomoteru , Kumata Katsushi , Yui Joji , Odawara Chika , Kawamura Kazunori , Hatori Akiko , Inoue Osamu , Yamaguchi Masatoshi , Suzuki Kazutoshi , Zhang Ming‐Rong 
Published: July 2009

AbstractThe aim of this study was to evaluateN‐benzyl‐N‐[11C]methyl‐2‐(7‐methyl‐8‐oxo‐2‐phenyl‐7,8‐dihydro‐9H‐purin‐9‐yl)acetamide ([11C]DAC) as a new translocator protein (18 kDa) [TSPO, formerly known as the peripheral‐type benzodiazepine receptor (PBR)] positron emission tomography (PET) ligand in normal mice and unilateral kainic acid (KA)‐lesioned rats. DAC is a derivative of AC‐5216, which is a potent and selective PET ligand for the clinical investigation of TSPO. The binding affinity and selectivity of DAC for TSPO were similar to those of AC‐5216, and DAC was less lipophilic than AC‐5216. The distribution pattern of [11C]DAC was in agreement with TSPO distribution in rodents. No radioactive metabolite of [11C]DAC was found in the mouse brain, although it was metabolized rapidly in mouse plasma. Using small‐animal PET, we examined the in vivo binding of [11C]DAC for TSPO in KA‐lesioned rats. [11C]DAC and [11C]AC‐5216 exhibited similar brain uptake in the lesioned and nonlesioned striatum, respectively. The binding of [11C]DAC to TSPO was increased significantly in the lesioned striatum, and [11C]DAC showed good contrast between the lesioned and nonlesioned striatum (the maximum ratio was about threefold). In displacement experiments, the uptake of [11C]DAC in the lesioned striatum was eventually blocked using an excess of either unlabeled DAC or PK11195 injected. [11C]DAC had high in vivo specific binding to TSPO in the injured rat brain. Therefore, [11C]DAC is a useful PET ligand for TSPO imaging, and its specific binding to TSPO is suitable as a new biomarker for brain injury. Synapse 63:961–971, 2009. © 2009 Wiley‐Liss, Inc.
Endocannabinoid modulation of amphetamine sensitization is disrupted in a rodent model of lesion‐induced dopamine dysregulation
Authors: Eisenstein Sarah A. , Holmes Philip V. , Hohmann Andrea G. 
Published: July 2009

AbstractWe tested the hypothesis that increased dopaminergic sensitivity induced by olfactory bulbectomy is mediated by dysregulation of endocannabinoid signaling. Bilateral olfactory bulbectomy induces behavioral and neurobiological symptomatology related to increased dopaminergic sensitivity. Rats underwent olfactory bulbectomy or sham operations and were assessed 2 weeks later in two tests of hyperdopaminergic responsivity: locomotor response to novelty and locomotor sensitization to amphetamine. Amphetamine (1 mg/kg i.p.) was administered to rats once daily for 8 consecutive days to induce locomotor sensitization. URB597, an inhibitor of the anandamide hydrolyzing enzyme fatty‐acid amide hydrolase (FAAH), was administered daily (0.3 mg/kg i.p.) to sham and olfactory bulbectomized (OBX) rats to investigate the impact of FAAH inhibition on locomotor sensitization to amphetamine. Pharmacological specificity was evaluated with the CB1 antagonist/inverse agonist rimonabant (1 mg/kg i.p). OBX rats exhibited heightened locomotor activity in response to exposure either to a novel open field or to amphetamine administration relative to sham‐operated rats. URB597 produced a CB1‐mediated attenuation of amphetamine‐induced locomotor sensitization in sham‐operated rats. By contrast, URB597 failed to inhibit amphetamine sensitization in OBX rats. The present results demonstrate that enhanced endocannabinoid transmission attenuates development of amphetamine sensitization in intact animals but not in animals with OBX‐induced dopaminergic dysfunction. Our data collectively suggest that the endocannabinoid system is compromised in olfactory bulbectomized rats. Synapse 63:941–950, 2009. © 2009 Wiley‐Liss, Inc.
Differential corticosteroid receptor regulation of mesoaccumbens dopamine efflux during the peak and nadir of the circadian rhythm: A molecular equilibrium in the midbrain?
Authors: Tye Susannah J. , Miller Anthony D. , Blaha Charles D. 
Published: July 2009

AbstractCorticosteroid receptor modulation of mesoaccumbens dopamine neurotransmission is believed to be a key neurobiological mechanism mediating the effects of stress in addiction. Importantly, nucleus accumbens (NAc) subregions (core and shell) are reported to respond differentially to fluctuating basal levels of glucocorticoids, with dopaminergic responses in the core of the NAc being somewhat impervious to fluctuating levels of glucocorticoids relative to the shell. To investigate the corticosteroid receptor mechanisms mediating basal dopamine efflux in the core of the NAc, we have used chronoamperometry in combination with stearate‐modified graphite paste electrodes in urethane anesthetized male Long–Evans rats during the peak and nadir of the circadian cycle. Blockade of ventral tegmental area low‐affinity glucocorticoid (GR) or high‐affinity mineralocorticoid (MR) receptors with mifepristone (1 μg/μl) or spironolactone (0.2 μg/μl), respectively, indicated that endogenous phase‐dependent corticosteroid receptor activation (GRs during peak; MRs during nadir) facilitated extracellular NAc dopamine efflux. Conversely, the alternate receptor's actions appeared inhibitory at these time points (MRs during peak; GRs during nadir). Pharmacological activation of either the GR or MR with corticosterone (2 μg/μl) or aldosterone (0.2 μg/μl), respectively, potentiated NAc dopamine efflux, irrespective of circadian phase. Together, these data suggest that dominant corticosteroid receptor activation stimulates tonic mesoaccumbens dopamine transmission, enabling MRs and GRs to differentially maintain basal NAc dopamine release over the course of the circadian cycle. This points to an important molecular mechanism through which relatively stable NAc core dopamine extracellular levels could be maintained in the face of fluctuating corticosterone circadian rhythms. Synapse 63:982–990, 2009. © 2009 Wiley‐Liss, Inc.
Roadmap for Optimization
Authors: Said Yasmin , Wegman Edward 
Published: July 2009

AbstractThis article, first published online on July 13, 2009 in Wiley Online Library (http://www.wileyonlinelibrary.com), has been revised at the request of the Editors‐in‐Chief and the Publisher. References and links have been added to aid the reader interested in following up on any technique. Please follow the link to the Supporting Information to view the original version of this article.http://onlinelibrary.wiley.com/doi/10.1002/wics.16/suppinfoThis article is intended as a broad overview of optimization. While often considered as a subset of operations research, optimization is a central concept for statistical theory, e.g., maximum likelihood, least squares, minimum entropy, minimum loss and risk, and so on. As data set sizes become larger, the computational framework of optimization becomes more important. In this article we cover mathematical programming, linear programming, dynamic programming, calculus of variations, and metaheuristic methods. Copyright © 2009 John Wiley & Sons, Inc.This article is categorized under:Algorithms and Computational Methods > Least SquaresAlgorithms and Computational Methods > Convex OptimizationAlgorithms and Computational Methods > Linear ProgrammingAlgorithms and Computational Methods > Dynamic ProgrammingAlgorithms and Computational Methods > Quadratic and Nonlinear ProgrammingAlgorithms and Computational Methods > Genetic Algorithms and Evolutionary ComputingAlgorithms and Computational Methods > Simulated AnnealingAlgorithms and Computational Methods > Maximum Likelihood Methods
Antithetic variates
Authors: Gentle James E. 
Published: July 2009

AbstractAntithetic variates are used to reduce the experimental error in Monte Carlo experiments. Monte Carlo experiments use random numbers as the fundamental experimental units. The basic idea in antithetic variates is to introduce experimental units that are negatively correlated with other experimental units. The variance of the mean of two such units is the mean of their individual variances plus their negative covariance. Copyright © 2009 John Wiley & Sons, Inc.This article is categorized under:

Algorithms and Computational Methods > Random Number Generation
ATP‐loaded liposomes for treatment of myocardial ischemia
Authors: Hartner William C. , Verma Daya D. , Levchenko Tatyana S. , Bernstein Eugene A. , Torchilin Vladimir P. 
Published: July 2009

AbstractA major obstacle to drug therapy for treatment of potential myocardial infarction is the limited access to the ischemic myocardium by drugs in an active form. Encouraging results have been reported with liposomes loaded with ATP in a variety of in vitro and in vivo models. We describe methods for optimized encapsulation of ATP in liposomes, enhancement of their effectiveness by increasing circulation time, and targeting of injured myocardial cells with surface attached antimyosin. In isolated ischemic rat hearts, ATP‐loaded liposomes and ATP‐loaded immunoliposomes effectively protected myocardium from ischemia/reperfusion damage as measured by systolic and diastolic functional improvements. In vivo, in rabbits with induced localized myocardial ischemia, liposomal encapsulation of ATP significantly diminished the proportion of ventricular muscle at risk that was irreversibly damaged during reperfusion. Therefore, ATP encapsulated in liposomes can provide an effective exogenous source for in vivo application which can protect ischemically damaged hearts. Copyright © 2009 John Wiley & Sons, Inc.This article is categorized under:

Therapeutic Approaches and Drug Discovery > Nanomedicine for Cardiovascular Disease
Analysis of Iranian postage stamps belonging to the Qajar dynasty (18th–20th century's) by micro‐PIXE
Authors: Oliaiy P. , Agha‐Aligol D. , Shokouhi F. , Lamehi‐Rachti M. 
Published: July 2009

AbstractEighteen historical Iranian postage stamps belonging to the Qajar dynasty were analyzed by micro‐particle induced X‐ray emission (PIXE) and complementary techniques using Van de Graaff accelerator in the Nuclear Science and Technology Research Institute in Iran. The aim of this study was to determine the elemental composition of different papers and inks of Iranian stamps printed in the Netherlands, Austria, France and Iran. The results obtained in this work show differences between elemental composition of stamps printed in different places and indicate that micro‐PIXE is a suitable technique for this kind of analysis. Copyright © 2009 John Wiley & Sons, Ltd.