bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ancillary testing in children with rotavirus gastroenteritis
Authors: Rowinsky Peter A. , Steenhoff Andrew P. , Kung Shiang‐Ju , Arbeter Allan , Shah Samir S. 
Published: September 2009

AbstractOBJECTIVES:Costly microbiological assays are frequently performed in patients with rotavirus gastroenteritis (RGE) to exclude concurrent serious bacterial infection (SBI). The incidence of concurrent SBI in this population is unknown but estimated to be low. The primary objective was to describe the incidence of SBI in children with RGE. The secondary objective was to elucidate risk factors for prolonged length of stay (LOS) in the cohort.METHODS:All children ≤18 years seen at a community hospital for laboratory‐confirmed RGE over a 4‐year period were included in a retrospective cohort study to describe the incidence of concurrent SBI and to identify risk factors for prolonged LOS. Prolonged LOS was defined as hospitalization for ≥3 days.RESULTS:Ninety‐four cases of RGE were identified; 58 (61.7%) males and 80 (85.1%) African Americans. The median age was 8 months (interquartile range [IQR], 1 month to 16 years) and 83 patients (88.3%) required admission. There were no cases of SBI. The median LOS was 2 days. Age ≤ 6 months (adjusted odds ratio [OR], 3.0; 95% confidence interval [CI], 1.2‐7.7; P = 0.022) and collection of a peripheral blood culture (adjusted OR, 2.7; 95% CI, 1.0‐7.1; P = 0.043) were associated with LOS ≥ 3 days.CONCLUSIONS:In children evaluated at a community hospital with laboratory‐confirmed RGE, no episodes of SBI occurred. This finding challenges the need to perform invasive, costly, microbiological assays to exclude concurrent SBI in this population. Children 6 months and younger were at increased risk of prolonged hospitalization from RGE. Journal of Hospital Medicine 2009;4:E36–E40. © 2009 Society of Hospital Medicine.
Polar phonon mode selection rules in tip‐enhanced Raman scattering
Authors: Berweger Samuel , Raschke Markus B. 
Published: September 2009

AbstractWe discuss the use of the symmetry selectivity of phonon Raman scattering to determine nanocrystallographic information of solids using tip‐enhanced Raman scattering (TERS). The necessary degrees of freedom arise from the combination of the Raman selection rules reflecting crystal symmetry superimposed by the polarization and k‐vector‐dependent field enhancement and scattering of the scanning probe tip. The resulting phonon TERS selection rules are discussed, including the use of the crystal Raman tensor and momentum conservation for polar phonon modes. We demonstrate the selection rules for both far‐field and tip‐enhanced near‐field Raman scattering from bulk and nanocrystalline LiNbO3. Copyright © 2009 John Wiley & Sons, Ltd.
Raman and SERS study of metoclopramide at different pH values
Authors: Leopold Nicolae , Cîntǎ‐Pînzaru Simona , Szabó László , Ileşan Daniela , Chiş Vasile , Cozar Onuc , Kiefer Wolfgang 
Published: September 2009

AbstractConjugate acid–base forms of the drug metoclopramide were investigated by Raman spectroscopy in aqueous solutions and by surface‐enhanced Raman scattering (SERS), when the molecules were adsorbed on colloidal silver surfaces. Raman spectra were recorded at pH values below 8, metoclopramide being poorly water soluble at higher pH values. The SERS spectra of metoclopramide were recorded in the 3–11 pH range, even in spite of its low solubility at basic pH values. The Raman and SERS spectra were assigned by means of density functional theory (DFT) calculations. By monitoring several SERS marker bands, the protonated, neutral or the coexistence of both molecular species adsorbed on the colloidal silver particles could be evidenced. The adsorbate orientation was deduced to be perpendicular to the metal surface for the protonated molecular species and tilted for the neutral metoclopramide molecular species. Copyright © 2009 John Wiley & Sons, Ltd.
Raman spectra of organic acids obtained using a portable instrument at −5 °C in a mountain area at 2000 m above sea level
Authors: Jehlička J. , Vítek P. , Edwards H. G. M. 
Published: September 2009

AbstractWell‐resolved Raman spectra of organic acids were obtained with 785 nm excitation using a portable Raman instrument (Ahura First Defender XL) under low temperature −5 °C atmospheric conditions at an altitude of 2000 m (Axamer Lizum, Innental, Austria). The portable Raman spectrometer tested in this setting permits fast and unambiguous detection of solid forms of these organic acids (formic, acetic, valeric, hexanoic, heptanoic, isophthalic, ascorbic and mellitic) under field conditions. This demonstrates the possibility to use a miniaturized Raman spectrometer as a key instrument for investigating the presence of organic compounds and biomolecules under low temperature conditions. These results are important for future missions focusing not only on Mars, where Raman spectroscopy will be a key non‐destructive analytical tool for the in situ identification of organic compounds relevant to life detection on planetary surfaces or near sub‐surfaces. Copyright © 2009 John Wiley & Sons, Ltd.
Effect of temperature, pH and film thickness on nisin release from antimicrobial whey protein isolate edible films
Authors: Rossi‐Márquez Giovanna , Han Jung H , García‐Almendárez Blanca , Castaño‐Tostado Eduardo , Regalado‐González Carlos 
Published: September 2009

AbstractBACKGROUND:An active packaging film based on whey protein isolate (WPI) was developed by incorporating nisin to promote microbial food safety. The effect of temperature and pH on the release of nisin from edible films of different thickness was investigated. The film mechanical properties and inhibitory effect were also evaluated.RESULTS:Nisin release was significantly favoured by low pH, with the highest release after 24 h (1325 IU), which was not significantly affected by temperature (5 or 10 °C). Thickness significantly affected film elongation, with thicker films showing the highest elongation (54.3 ± 2.7%). Water vapour permeability (0.15 ± 0.4 g mm m−2kPa−1h−1) and elastic modulus were not significantly affected by thickness. The highest nisin effective diffusivity (5.88 × 10−14m2s−1) was obtained using a solution at pH 4, 112 µm film thickness and a temperature of 5 °C. More than four log cycles ofBrochotrix thermosphactawere reduced from the surface of a ham sample after 8 days of incubation at 4 °C by the active WPI film containing 473 IU cm−2nisin.CONCLUSION:Nisin diffusivity from WPI edible films was favoured at lower pH and film thickness. This active packaging film may be used to preserve the quality and safety of meat products. Copyright © 2009 Society of Chemical Industry
LC‐MS of streptomycin following desalting of a nonvolatile mobile phase and pH gradient
Authors: Pendela Murali , Hoogmartens Jos , Van Schepdael Ann , Adams Erwin 
Published: September 2009

AbstractStreptomycin (SM) is composed of streptidine, streptose and N‐methyl glucosamine sugar moieties. For the determination of SM and its related substances, an ion‐pair LC‐UV detection method using a Supelcosil LC‐ABZ column was developed previously. While analyzing commercial samples, several unknown compounds were detected. Most of these compounds are not yet characterized. In this study, the above LC method was coupled to MS for impurity profiling in a selected commercial sample. However, it could not be directly coupled to MS due to the presence of the nonvolatile salt, buffer and ion‐pair reagent in the mobile phase. So, for structural characterization, each peak eluted from the nonvolatile eluent system was collected and transferred to MS after the desalting process. In total, 16 compounds were studied, 15 compounds including 12 unknowns could be identified.
Rapid screening of beta‐adrenergic agents and related compounds in human urine for anti‐doping purpose using capillary electrophoresis with dynamic coating
Authors: Mazzarino Monica , de la Torre Xavier , Mazzei Franco , Botrè Francesco 
Published: September 2009

AbstractThis paper presents a capillary electrophoresis method, developed for the detection, in human urine, of beta‐adrenergic agents and phenolalkylamines. The electrophoretic separation is achieved in less than 10 min and is based on the use of CEofix kit, for the dynamic capillary coating. The effects of accelerator buffer pH and separation voltage were investigated. The optimum buffer pH was found to be 2.5 for beta2‐agonists and 6.2 for beta‐blockers and phenoalkylamines with a separation voltage of 15 kV. Urine samples spiked with the compounds here studied were treated according to the standard procedure (SPE and evaporation to dryness) and analyzed by CE interfaced with an UV diode‐array, set at 195 and 210 nm. The quantitative validation results, obtained analyzing samples at three different concentrations, show a good precision of peak areas that do not exceed 5% for intra‐day assays and 10% for inter‐day assays. Good linearity (r2 > 0.995) was obtained within the 50–500 ng/mL concentration range. The qualitative validation data show a relative migration times (MTs) variation lower than 1%. The analytes were clearly distinguishable in urine, with LOD and LOQ in the range of 10–80 and 40–100 ng/mL, respectively.
Kinetic and thermodynamic characterization of camptothecin hydrolysis at physiological pH in the absence and presence of human serum albumin
Authors: Thakur Rishi , Kunadharaju Sasank , Savva Michalakis 
Published: September 2009

AbstractTo accurately derive the kinetic and thermodynamic parameters governing the hydrolysis of the lactone ring at physiological pH, a derivative spectrophotometric technique was used for the simultaneous estimation of lactone and carboxylate forms of camptothecin (CPT). The hydrolysis of the CPT‐lactone and the lactonization of CPT‐carboxylate at 310.15 K followed a first‐order decay with apparent rate constants equal to 0.0279 ± 0.0016 min−1 and 0.0282 ± 0.0024 min−1, respectively. The activation energy associated with the hydrolysis of the CPT‐lactone and the lactonization of the CPT‐carboxylate as calculated from the Arrhenius equation was 89.18 ± 0.84 and 86.49 ± 2.7 kJ mol−1, respectively. The enthalpy and entropy of the thermodynamically favored hydrolysis reaction were on average 10.49 kJ mol−1 and 48.00 J K−1 mol−1, respectively. The positive enthalpy and entropy values of the CPT‐lactone hydrolysis indicate that the reaction is endothermic and entropically driven. The stability of CPT‐lactone in the presence of human serum albumin (HSA) was also analyzed. Notwithstanding the much faster hydrolysis of the CPT‐lactone in the presence of HSA at various temperatures, the energy of activation was determined to be similar to the one estimated in the absence of HSA, suggesting that HSA does not catalyze the hydrolysis reaction, but it merely binds, sequesters, and stabilizes the CPT‐carboxylate species. © 2009 Wiley Periodicals, Inc. Int J Chem Kinet 41: 704–715, 2009
Ab initio chemical kinetics for the NH2 + HNOx Reactions, Part I: Kinetics and Mechanism for NH2 + HNO
Authors: Xu Shucheng , Lin M. C. 
Published: September 2009

AbstractThe kinetics and mechanism for the reaction of NH2 with HNO have been investigated by ab initio calculations with rate constant prediction. The potential energy surface of this reaction has been computed by single‐point calculations at the CCSD(T)/6‐311+G(3df, 2p) level based on geometries optimized at the CCSD/6‐311++G(d, p) level. The major products of this reaction were found to be NH3 + NO formed by H‐abstraction via a long‐lived H2N⋅⋅⋅HNO complex and the H2NN(H)O radical intermediate formed by association with 26.9 kcal/mol binding energy. The rate constants for formation of primary products in the temperature range of 300–3000 K were predicted by variational transition state or RRKM theories. The predicted total rate constants at the 760 Torr Ar pressure can be represented by ktotal = 3.83 × 10−20 × T+2.47exp(1450/T) at T = 300–600 K; 2.58 × 10−22 × T+3.15 exp(1831/T) cm3 molecule−1 s−1 at T = 600−3000 K. The branching ratios of major channels at 760 Torr Ar pressure are predicted: k1 + k3 + k4 producing NH3 + NO accounts for 0.59–0.90 at T = 300–3000 K peaking around 1000 K, k2 accounts for 0.41–0.03 at T = 300–600 K decreasing with temperature, and k5 accounts for 0.07–0.27 at T > 600 K increasing gradually with temperature. The NH3 + NO formation rate constant was found to be a factor of 3–10 smaller than that of the isoelectronic reaction CH3 + HNO producing CH4 + NO, which has been shown to take place by barrierless H‐abstraction without involving a hydrogen‐bonding complex as in the NH2 case. © 2009 Wiley Periodicals, Inc. Int J Chem Kinet 41: 677–677, 2009
Advances in protein turnover analysis at the global level and biological insights
Authors: Li Qingbo 
Published: September 2009

AbstractThe concept of a dynamic state of body constituents, a precursor of the modern term of proteome dynamics, was conceived over a century ago. But, not until recently can we examine the dynamics of individual “constituents” for example, proteins at a truly global level. The path of advancement in our understanding of protein turnover at the global level is marked by the introduction of some key technological innovations. These methods include the isotopic tracer technique in the 1930s, the two‐dimensional gel electrophoresis technique in the 1970s, the sector mass spectrometer that could analyze isotopomers of peptides in the early 1990s, the 2D gel/MALDI‐TOF proteomics technology in the late 1990s, the booming liquid chromatography/mass spectrometry proteomics technology in this decade, and the recently emerging protein‐tagging approaches that offer single‐cell resolution for protein turnover measurements. The long‐standing inquiry raised in the 1950s about the existence of a dynamic state in different organisms at different physiological conditions can now be answered with an individual “constituent” resolution on a truly global scale. Now it appears that protein degradation is not necessarily an end to the protein function. Rather, it can be the start of a new function because protein degradation clears the way for the action of other proteins. Protein turnover participates in a multi‐layer complex regulatory network and shares equal importance with gene transcription and protein translation. The advances in technologies for protein turnover analysis and the improved understanding of the biological role of protein turnover will likely help to solve some long‐standing biomedical problems such as the tuberculosis disease that at the present day still affects one‐third of the world population. © 2009 Wiley Periodicals, Inc., Mass Spec Rev 29:717–736, 2010
Influence of apple polyphenols on inflammatory gene expression
Authors: Jung Mathias , Triebel Sven , Anke Timm , Richling Elke , Erkel Gerhard 
Published: September 2009

AbstractApples (Malusspp., Rosaceae) and products thereof contain high amounts of polyphenols which show diverse biological activities and may contribute to beneficial health effects, like protecting the intestine against inflammation initiated by chronic inflammatory bowel diseases (IBD). IBD are characterized by an excessive release of several proinflammatory cytokines and chemokines by different cell types which results consequently in an increased inflammatory response. In the present study we investigated the preventive effectiveness of polyphenolic juice extracts and single major constituents on inflammatory gene expression in immunorelevant human cell lines (DLD‐1, T84, MonoMac6, Jurkat) induced with specific stimuli. Besides the influence on proinflammatory gene expression, the effect on NF‐κB‐, IP‐10‐, IL‐8‐promoter‐, STAT1‐dependent signal transduction, and the relative protein levels of multiple released cytokines and chemokines were studied. DNA microarray analysis of several genes known to be strongly regulated during gastrointestinal inflammation, combined with quantitative real‐time PCR (qRT‐PCR) revealed that the apple juice extract AE04 (100–200 μg/mL) significantly inhibited the expression of NF‐κB regulated proinflammatory genes (TNF‐α, IL‐1β, CXCL9, CXCL10), inflammatory relevant enzymes (COX‐2, CYP3A4), and transcription factors (STAT1, IRF1) in LPS/IFN‐γ stimulated MonoMac6 cells without significant effects on the expression of house‐keeping genes. A screening of some major compounds of AE04 revealed that the flavan‐3‐ol dimer procyanidin B2is mainly responsible for the anti‐inflammatory activity of AE04. Furthermore, the dihydrochalcone aglycone phloretin and the dimeric flavan‐3‐ol procyanidin B1significantly inhibited proinflammatory gene expression and repressed NF‐κB‐, IP‐10‐, IL‐8‐promoter‐, and STAT1‐dependent signal transduction in a dose‐dependent manner. The influence on proinflammatory gene expression by the applied polyphenols thereby strongly correlated with the increased protein levels investigated by human cytokine array studies. In summary, we evaluated selected compounds responsible for the anti‐inflammatory activity of AE04. In particular, procyanidin B1, procyanidin B2, and phloretin revealed anti‐inflammatory activitiesin vitroand therefore may serve as transcription‐based inhibitors of proinflammatory gene expression.
Important roles of the hyphenated HPLC‐DAD‐MS‐SPE‐NMR technique in metabonomics
Authors: Tang Huiru , Xiao Chaoni , Wang Yulan 
Published: September 2009

AbstractMetabolite identification is a key step for metabonomics study. A fully automated hyphenation of HPLC‐diode‐array detector (DAD) mass spectrometry (MS) solid phase extraction (SPE)–NMR spectroscopy (HPLC‐DAD‐MS‐SPE‐NMR) is one of the most efficient methods to determine the structure of a given unknown metabolite in a complex mixture (metabonome) and hence represents one of the most important analytical techniques for the further development of metabonomics. In this review, some recent applications of this technique in identifying novel and trace metabolites in plant extracts and drug metabolism have been discussed. Modification of this hyphenated technique, enabling multiple trappings of strong polar metabolites for biofluids, needs further development. Copyright © 2009 John Wiley & Sons, Ltd.
Pure and mixed gas permeation through a composite polydimethylsiloxane membrane
Authors: Sadrzadeh Mohtada , Amirilargani Mohammad , Shahidi Kazem , Mohammadi Toraj 
Published: September 2009

AbstractA thin polydimethylsiloxane (PDMS) layer on polyethersulfone (PES) support was synthesized and pure and mixed gas permeation of C3H8, CH4, and H2 through it was measured. At first, a macroporous PES support was prepared by using the phase inversion method and characterized. Then, a thin layer of PDMS was coated over the support. Finally, permeation behavior of the synthesized composite membrane was investigated by pure and mixed gas experiments under various operating conditions. The synthesized PDMS/PES membrane showed much better gas permeation performance than others reported in the literature. Pure gas experiments showed that increase in the transmembrane pressure increases the permeability coefficient of heavier gases, C3H8, while decreases those of lighter ones, CH4 and H2. Exactly opposite behavior was observed in mixed gas experiments due to the competitive sorption and diffusion in the plasticized polymer matrix. Temperature was realized to induce similar effects on the permeability of pure and mixed gases. As expected, in rubbery membranes such as PDMS, permeability values of more condensable gases decrease with increasing temperature, whereas those of permanent gases increase. In the case of mixed gas experiments, increase in the C3H8 concentration in feed led to increase in the permeabilities of all the components due to the C3H8‐induced swelling of the PDMS film. High C3H8/H2 and C3H8/CH4 ideal selectivities of 22.1 and 14.7, respectively, at a transmembrane pressure of 7 atm as well as reasonable C3H8 separation factor (SF) values for all mixed gas experiments (in the range of 8.1–16.8) demonstrated the ability of the synthesized PDMS/PES membrane for the separation of organic vapors from permanent gases. Copyright © 2009 John Wiley & Sons, Ltd.
Data mining on electronic health record databases for signal detection in pharmacovigilance: which events to monitor?
Authors: Trifirò Gianluca , Pariente Antoine , Coloma Preciosa M. , Kors Jan A. , Polimeni Giovanni , Miremont‐Salamé Ghada , Catania Maria Antonietta , Salvo Francesco , David Anaelle , Moore Nicholas , Caputi Achille Patrizio , Sturkenboom Miriam , Molokhia Mariam , Hippisley‐Cox Julia , Acedo Carlos Diaz , van der Lei Johan , Fourrier‐Reglat Annie 
Published: September 2009

AbstractPurposeData mining on electronic health records (EHRs) has emerged as a promising complementary method for post‐marketing drug safety surveillance. The EU‐ADR project, funded by the European Commission, is developing techniques that allow mining of EHRs for adverse drug events across different countries in Europe. Since mining on all possible events was considered to unduly increase the number of spurious signals, we wanted to create a ranked list of high‐priority events.MethodsScientific literature, medical textbooks, and websites of regulatory agencies were reviewed to create a preliminary list of events that are deemed important in pharmacovigilance. Two teams of pharmacovigilance experts independently rated each event on five criteria: ‘trigger for drug withdrawal’, ‘trigger for black box warning’, ‘leading to emergency department visit or hospital admission’, ‘probability of event to be drug‐related’, and ‘likelihood of death’. In case of disagreement, a consensus score was obtained. Ordinal scales between 0 and 3 were used for rating the criteria, and an overall score was computed to rank the events.ResultsAn initial list comprising 23 adverse events was identified. After rating all the events and calculation of overall scores, a ranked list was established. The top‐ranking events were: cutaneous bullous eruptions, acute renal failure, anaphylactic shock, acute myocardial infarction, and rhabdomyolysis.ConclusionsA ranked list of 23 adverse drug events judged as important in pharmacovigilance was created to permit focused data mining. The list will need to be updated periodically as knowledge on drug safety evolves and new issues in drug safety arise. Copyright © 2009 John Wiley & Sons, Ltd.
Systematic reviews of adverse effects of drug interventions: a survey of their conduct and reporting quality
Authors: Cornelius V. R. , Perrio M. J. , Shakir S. A.W. , Smith L. A. 
Published: September 2009

AbstractPurposeThere is a need for high quality evidence on the adverse effects of medical interventions to inform policy, practice and research. Methods to systematically review adverse effects have not been fully developed. We aimed to assess the current methods and reporting used by such reviews.MethodsSurvey of general medical, drug safety and pharmacology journals published in 2006. Methods including: searching, inclusion criteria, quality assessment and meta‐analysis were assessed.ResultsForty three systematic reviews from 2704 abstracts in 16 journals were included. The search strategy was not reported by 10 (23%) of reviews. The collection and reporting of the adverse effects from primary studies was described by 4/37 (12%) reviews and the quality of included studies was assessed by 15 (35%) of reviews. Meta‐analysis on rare outcomes and handing of zero event data were inconsistent. A polarity in the standard of reporting between reviews was observed. The reporting standard we found was similar to another survey of systematic reviews.ConclusionReporting was poor with respect to searching and definition/collection of adverse effects and guidelines such as QUOROM and MOOSE could be employed by authors. Comprehensive and clear reporting should be enforced by journals. The low proportion of reviews assessing quality, and the inconsistencies observed when modelling rare event data reflect the need for empirical research to underpin methods in these areas. Copyright © 2009 John Wiley & Sons, Ltd.