bluuebunny/crossref_metadata_2025_split huggingface dataset:
Binding Modes in Metal Ion Complexes of Quinones and Semiquinone Radical Anions: Electron‐Transfer Reactivity
Authors: Yuasa Junpei , Suenobu Tomoyoshi , Fukuzumi Shunichi 
Published: March 2006

Abstract9,10‐Phenanthrenequinone (PQ) and 1,10‐phenanthroline‐5,6‐dione (PTQ) form 1:1 and 2:1 complexes with metal ions (M n+=Sc 3+, Y 3+, Mg 2+, and Ca 2+) in acetonitrile (MeCN), respectively. The binding constants of PQM n+ complexes vary depending on either the Lewis acidity or ion radius of metal ions. The one‐electron reduced species (PTQ⋅‐) forms 1:1 complexes with M n+, and PQ⋅‐ also forms 1:1 complexes with Sc3+, Mg2+, and Ca2+, whereas PQ⋅‐ forms 1:2 complexes with Y3+ and La3+, as indicated by electron spin resonance (ESR) measurements. On the other hand, semiquinone radical anions (Q⋅‐ and NQ⋅‐) derived from p‐benzoquinone (Q) and 1,4‐naphthoquinone (NQ) form Sc3+‐bridged π‐dimer radical anion complexes, Q⋅‐(Sc3+)nQ and NQ⋅‐(Sc3+)n‐NQ (n=2 and 3), respectively. The one‐electron reduction potentials of quinones (PQ, PTQ, and Q) are largely positively shifted in the presence of M n+. The rate constant of electron transfer from CoTPP (TPP2−=dianion of tetraphenylporphyrin) to PQ increases with increasing the concentration of Sc3+ to reach a constant value, when all PQ molecules form the 1:1 complex with Sc3+. Rates of electron transfer from 10,10′‐dimethyl‐9,9′‐biacridine [(AcrH)2] to PTQ are also accelerated significantly by the presence of Sc3+, Y3+, and Mg2+, exhibiting a first‐order dependence with respect to concentrations of metal ions. In contrast to the case of o‐quinones, unusually high kinetic orders are observed for rates of Sc3+‐promoted electron transfer from tris(2‐phenylpyridine)iridium(III) [Ir(ppy)3] to p‐quinones (Q): second‐order dependence on concentration of Q, and second‐ and third‐order dependence on concentration of Sc3+ due to formation of highly ordered radical anion complexes, Q⋅(Sc3+)nQ (n=2 and 3).
Habit learning and anorexia nervosa: A cognitive neuroscience hypothesis
Authors: Steinglass Joanna , Walsh B. Timothy 
Published: March 2006

AbstractObjective:Anorexia nervosa (AN) is characterized by abnormal behaviors involving eating and weight that are impressively resistant to change. The persistence of these behaviors likely plays an important role in the high relapse rate after initial treatment. Persistent, stereotyped behaviors are also characteristic of obsessive‐compulsive disorder (OCD). This article presents a neurocognitive model of AN, based on comparisons with OCD.Method:This article reviews clinical, neuropsychological, and neuroimaging findings in both OCD and AN relevant to a neurobiological understanding of a potential mechanism of the perpetuation of AN.Results:The identification of specific neurocognitive disturbances in individuals with OCD has led to a compelling hypothesis of the neural mechanisms mediating this disorder. Evidence suggests that similar disturbances, involving neural circuits between the cortex and the basal ganglia, may be present in individuals with AN.Conclusion:Research on such neurocognitive disturbances has the potential both to inform understanding of neural mechanisms underlying AN and to lead to advances in treatment. © 2006 by Wiley Periodicals, Inc., Int J Eat Disord, 2006
Girls with anorexia nervosa as young adults: Personality, self‐esteem, and life satisfaction
Authors: Halvorsen Inger , Heyerdahl Sonja 
Published: March 2006

AbstractObjective:The current study evaluated personality, self‐esteem, and life satisfaction in former patients with different outcomes of childhood and adolescent‐onset anorexia nervosa (AN).Methods:Forty‐four female patients with AN were assessed 8.5 ± SD 3.4 years after treatment start with a clinical interview and questionnaires including the Temperament and Character Inventory (TCI) and the Rosenberg Self‐Esteem Scale. Self‐esteem and general life satisfaction in former patients were compared with women in a large population study.Results:Former AN patients with no eating disorder and normal eating attitudes at follow‐up (n = 21 [48%]) had similar TCI profiles and self‐esteem as samples from normal populations, whereas participants with poorer outcome had significantly lower TCI Self Directedness, self‐esteem, and life satisfaction scores. Life satisfaction was reduced in all outcome groups and was strongly associated with self‐esteem.Conclusion:Personality, self‐esteem, and life satisfaction varied significantly between outcome groups. The results indicate that young patients with AN with a good outcome may have normal personality and self‐esteem features in young adulthood. © 2006 by Wiley Periodicals, Inc., Int J Eat Disord, 2006
Artificial sweetener use among individuals with eating disorders
Authors: Klein Diane A. , Boudreau Gillian S. , Devlin Michael J. , Walsh B. Timothy 
Published: March 2006

AbstractWomen with eating disorders report using large quantities of artificially sweetened products, but this has not been quantified.ObjectiveThe authors assessed the use of selected artificially sweetened low‐calorie products among women with eating disorders compared with controls.MethodThirty women with anorexia nervosa (18 with the restricting subtype [AN‐R] and 12 with the binge/purge subtype [AN‐B/P]), 48 women with bulimia nervosa (BN), and 32 healthy control women completed a survey of frequency and amount of consumption of chewing gum, artificially sweetened low‐calorie beverages, and packets of artificial sweetener in the previous month.ResultsA greater proportion of women with AN‐B/P and BN reported use of each product, compared with women with AN‐R and control participants. Among product users, patients with eating disorders reported using greater amounts than controls. Among patients who reported binge eating and/or purging, the quantity of each product used was inversely correlated with body mass index (BMI).ConclusionThese data suggest an increased drive for sweet orosensory stimulation in women with AN and BN. © 2006 by Wiley Periodicals, Inc., Int J Eat Disord, 2006
Death due to duodenal obstruction in a patient with an eating disorder: A case report
Authors: Ikegaya Hiroshi , Nakajima Makoto , Shintani‐Ishida Kaori , Uemura Koichi , Yoshida Ken‐ichi 
Published: March 2006

AbstractObjective:A 30‐year‐old woman with a 2‐year history of bulimia nervosa and severe abdominal pain after excessive food consumption visited our emergency room. Her abdomen showed marked generalized distension.Method:Aspiration of the gastric contents was not successful, and despite efforts to resuscitate her, the patient died.Result:An autopsy showed a markedly distended stomach containing approximately 6,500 ml of solid foods. The aortomesenteric distance was <1.0 cm and the aortomesenteric angle was <20°, suggesting superior mesenteric artery (SMA) syndrome may have been a cause of death.Conclusion:However, her condition was also consistent with duodenal obstruction due to a heavy stomach and high intra‐abdominal pressure, and her cause of death was diagnosed as intestinal obstruction due to an excessive volume of food. © 2006 by Wiley Periodicals, Inc., Int J Eat Disord, 2006
Determination of enkephalin peptides by nonaqueous capillary electrophoresis with electrochemical detection
Authors: Psurek Arndt , Matysik Frank‐Michael , Scriba Gerhard K. E. 
Published: March 2006

AbstractNonaqueous capillary electrophoresis with electrochemical detection (NACE‐ED) was applied to the analysis of enkephalin peptides. The effect of different buffer compositions on the electrophoretic behavior of methionine enkephalin, leucine enkephalin, and [D‐Ala2]‐leucine enkephalin was studied. Separation of the protonated and the deprotonated peptides was obtained using ACN/methanol‐based electrolyte systems. The electrochemical behavior of the enkephalins was studied by the capillary batch injection analysis technique. NACE‐ED yielded well‐defined signals in the oxidation mode only for the negatively charged analytes. The optimized BGE for the counterelectroosmotic separation consisted of 10 mM ammonium acetate in ACN/methanol (3:1 v/v). Using a platinum microdisk electrode set to an actual potential of +0.65 V detection limits in the submicromolar range were observed which are about one order of magnitude lower compared to UV detection. Problems concerning EOF instability and electrode fouling caused by water and other neutral sample impurities transported by the EOF can be avoided in the EOF‐inverted mode using poly(ethylene glycol)‐coated capillaries and an actual working electrode potential of +1.0 V. For the quantification of the enkephalins [D‐Ala2]leucine enkephalin was used as internal standard. The practical utility for the determination of enkephalins in spiked plasma samples after SPE was demonstrated.
High‐resolution computer simulation of the dynamics of isoelectric focusing using carrier ampholytes: Focusing with concurrent electrophoretic mobilization is an isotachophoretic process
Authors: Thormann Wolfgang , Mosher Richard A. 
Published: March 2006

AbstractFocusing of four hemoglobins with concurrent electrophoretic mobilization was studied by computer simulation. A dynamic electrophoresis simulator was first used to provide a detailed description of focusing in a 100‐carrier component, pH 6–8 gradient using phosphoric acid as anolyte and NaOH as catholyte. These results are compared to an identical simulation except that the catholyte contained both NaOH and NaCl. A stationary, steady‐state distribution of carrier components and hemoglobins is produced in the first configuration. In the second, the chloride ion migrates into and through the separation space. It is shown that even under these conditions of chloride ion flux a pH gradient forms. All amphoteric species acquire a slight positive charge upon focusing and the whole pattern is mobilized towards the cathode. The cathodic gradient end is stable whereas the anodic end is gradually degrading due to the continuous accumulation of chloride. The data illustrate that the mobilization is a cationic isotachophoretic process with the sodium ion being the leading cation. The peak height of the hemoglobin zones decreases somewhat upon mobilization, but the zones retain a relatively sharp profile, thus facilitating detection. The electropherograms that would be produced by whole column imaging and by a single detector placed at different locations along the focusing column are presented and show that focusing can be commenced with NaCl present in the catholyte at the beginning of the experiment. However, this may require detector placement on the cathodic side of the catholyte/sample mixture interface.
Flow‐through partial‐filling affinity capillary electrophoresis using a crossreactive antibody for enantiomeric separations
Authors: Grubor Nenad M. , Armstrong Daniel W. , Jankowiak Ryszard 
Published: March 2006

AbstractIt is demonstrated that the separation of diastereoisomers and enantiomers can be accomplished by the flow‐through partial‐filling affinity CE using a crossreactive mAb. This approach revealed differences in the binding strength of the (±)‐cis‐ and (±)‐trans‐benzo[a]pyrene tetrols with the anti‐polycyclic aromatic hydrocarbon mAb and demonstrated that (+)‐enantiomers are more strongly immunocomplexed than their (−)‐counterparts. It is proposed that crossreactive monoclonal antibodies (i.e. mAb raised against achiral molecule and possessing limited selectivity) could be effectively utilized for specific stereoisomeric differentiation and chiral separations.
Preparation and characterisation of dual‐layer latex‐coated columns for open‐tubular capillary electrochromatographic preconcentration of cations combined in‐line with their separation by capillary electrophoresis
Authors: Zhang Shusheng , Macka Miroslav , Haddad Paul R. 
Published: March 2006

AbstractA dual‐layer ion‐exchange latex‐coated column was prepared and characterised for on‐capillary preconcentration of cations using an open‐tubular ion‐exchange CEC format. After preconcentration, the analyte cations were eluted with a transient isotachophoretic gradient and separated by CE. The latex double layer was established by first coating the negatively charged wall of the capillary with a layer of cationic quaternary ammonium anion‐exchange Dionex AS5A latex particles (60 nm diameter), and then coating a layer of anionic sulphonated cation‐exchange Dionex CS3 latex particles (300 nm diameter) onto the underlying AS5A layer. The adhesion of layers is based on electrostatic attractions. Several dual‐layer capillaries were characterised for their EOF and ion‐exchange capacity and this showed that coatings could be prepared reproducibly by a simple flushing procedure. The dual‐layer columns exhibited a moderate, pH‐independent EOF (ca. 26×10−9 m2 V−1s−1) and an ion‐exchange capacity of 57 µequiv./g (or 2.69 nequiv./column). Using an 8 cm length of coated capillary combined with a 72 cm length of untreated capillary, a method for on‐line preconcentration and separation of monovalent organic bases, alkali metal ions and alkaline earth metal ions by CE was developed. Recoveries for the preconcentration step were 48% for 4‐methylbenzylammonium, 43% for benzylammonium, 30–32% for alkali metal ions and 71–75% for alkaline earth cations. In all cases, recoveries were reproducible with RSDs being less than 6.2%. The influences of the ion‐exchange selectivity coefficient of the analyte and the sample‐loading rate on analyte recovery were also examined. The proposed method was utilised for the determination of alkaline earth cations and low µM detection limits were obtained.
Capillary zone electrophoresis of glycopeptides under controlled electroosmotic flow conditions coupled to electrospray and matrix‐assisted laser desorption/ionization mass spectrometry
Authors: Amon Sabine , Plematl Alexander , Rizzi Andreas 
Published: March 2006

AbstractDefined conditions of EOF along with different pH values of the BGE were compared for the purpose of analyzing glycopetides by CZE coupled to MS (CZE‐MS). Hyphenation to MS involved ESI as well as MALDI, and single‐stage and multistage MS were applied. Variation of the EOF was accomplished by selecting appropriate coatings for the capillary, namely hexadimethrine bromide (HDMB) and HDMB/dextran sulfate. A high and reproducible anodic and cathodic EOF, respectively, was obtained in both approaches, allowing the detection of analytes with net positive as well as negative charge in one single run. Thus, a fast and sensitive determination of the glycopeptides in a tryptic digest of antithrombin, chosen as a test sample, was achieved. Ionization suppression effects, a phenomenon typically observed with glycopeptides in MS analysis, were minimized thanks to separation from other peptides present. The high stability of the coatings permitted the generation of mass spectra without interfering peaks originating from the coating polymers. The high EOF generated by the coatings facilitated the maintenance of a stable spray when coupling to ESI‐MS, and a stable CZE current when working with a sheath flow‐assisted analyte deposition onto MALDI targets, respectively. In conclusion, CZE‐MS could be demonstrated as a robust complementary method to capillary RP‐HPLC‐MS in combination with both soft‐ionization techniques, ESI and MALDI, generally, and particularly in the context of glycopeptide analysis.
High‐speed biomarker identification utilizing porous silicon nanovial arrays and MALDI‐TOF mass spectrometry
Authors: Finnskog David , Jaras Kerstin , Ressine Anton , Malm Johan , Marko‐Varga György , Lilja Hans , Laurell Thomas 
Published: March 2006

AbstractSpeed and accuracy are crucial prerequisites in the application of proteomic methods to clinical medicine. We describe a microfluidic‐based nanovial array for rapid proteolytic processing linked to MALDI‐TOF MS. This microscale format consumes only minute amounts of sample, and it is compatible with rapid bioanalytical protocols and high‐sensitivity readouts. Arrays of vials (300 µm in diameter and 25 µm deep), isotropically etched in silicon wafers were electrochemically porosified. Automated picoliter microdispensing was employed for precise fluid handling in the microarray format. Vials were prefilled with trypsin solution, which was allowed to dry. Porosified and nonporosified nanovials were compared for trypsin digestion and subsequent MS identification of three model proteins: lysozyme, alcohol dehydrogenase, and serum albumin at levels of 100 and 20 fmol. In an effort to assess the rapid digestion platform in a context of putative clinical applications, two prostate cancer biomarkers, prostate‐specific antigen (PSA) and human glandular kallikrein 2 (hK2), were digested at levels of 100 fmol (PSA), 20 fmol (PSA) and 8 fmol (hK2). All biomarker digestions were completed in less than 30 s, with successful MS identification in the porous nanovial setting.
Fluid flow analysis of TCP flows in a DiffServ environment
Authors: Barbera Mario , Lombardo Alfio , Schembra Giovanni , Trecarichi C. Andrea 
Published: March 2006

AbstractThe differentiated services (DiffServ) architecture allows IP networks to offer different QoS levels to different users and applications. In this architecture, routers in the core network offer the same per‐hop behaviour (PHB) to all packets classified as belonging to the same class at the edge of the network. One of the most important types of PHB is assured forwarding (AF) PHB. Within each AF class, IP packets can be marked with different drop precedence (DP) values, and treated differently in congested DS nodes. To this end, DiffServ nodes in the core network implement active queue management (AQM) mechanisms. The target of this paper is to provide network designers with an accurate fluid‐flow analytical model of a DiffServ network, where the RED with in/out and coupled average queues (RIO‐C), RED with in/out and decoupled average queues (RIO‐DC) and Weighted RED (WRED) AQM techniques are implemented. We address a network simultaneously loaded with both greedy and data‐limited TCP flows, and we consider one AF class in which two DPs are defined, one for packets complying with the negotiated profile (IN packets), and another for packets that do not respect it (OUT packets). A token bucket marking mechanism is modelled for this purpose. The proposed model is applied to a complex network topology. Comparison between model and simulation results demonstrates that the model is able to capture both transient and steady‐state network behaviour with a high degree of accuracy, even when not all network routers implement the same AQM technique. These characteristics make our modelling approach suitable to address the issue of network parameter optimisation. As an example, the link capacity dimensioning problem in a DiffServ domain by means of an iterative optimisation algorithm is presented. Copyright © 2006 AEIT
Array CGH of fusion gene–positive leukemia‐derived cell lines reveals cryptic regions of genomic gain and loss
Authors: Horsley Sharon W. , Mackay Alan , Iravani Marjan , Fenwick Kerry , Valgeirsson Haukur , Dexter Tim , Ashworth Alan , Kearney Lyndal 
Published: March 2006

AbstractHuman leukemia–derived cell lines containing characteristic chromosomal translocations and inversions have been instrumental in identifying fusion genes implicated in the pathogenesis of the corresponding leukemia. Although chimeric fusion genes usually provide early and essential steps in the development of leukemia, they are not in themselves sufficient, requiring additional genetic events. The nature of these secondary, cooperating genetic events is not known. The advent of genome wide microarray‐based methods for assessing copy number changes made it possible to search for cytogenetically invisible regions of chromosome imbalance. We used BAC microarrays with a resolution of 1 Mb to determine whether cryptic regions of deletion or gain were associated with specific leukemia‐associated fusion genes in a series of cell lines. To complement the array analysis, we also applied 24‐color karyotyping by M‐FISH. This revealed cryptic chromosomal translocations and regions of loss or gain in all the cell lines studied. The chromosomal origin of previously unidentified marker chromosomes was revealed. In all cases, chromosomes described as monosomic were shown to be involved in unbalanced translocations with concurrent loss and/or gain of chromosomal material. The extent of these amplified and deleted regions was more accurately defined. Finally, small regions of deletion and amplification, often including genes known to be involved in leukemia progression (for example MYC, TP53, CDKN2A, and KIT), were identified. © 2006 Wiley‐Liss, Inc.
The effect of managed care on use of health care services: results from two contemporaneous household surveys
Authors: Deb Partha , Li Chenghui , K. Trivedi Pravin , M. Zimmer David 
Published: March 2006

AbstractThis paper estimates treatment effects of managed care plans on the utilization of health care services using data from two contemporaneous, nationally representative household surveys from the USA. The paper exploits recent advances in simulation‐based econometrics to take the endogeneity of enrollment into managed care plans into account and identify the causal relationship between managed care enrollment and utilization. Overall, results from the two surveys are remarkably similar, lending credibility to their external validity and to the econometric model and estimation methods. There is significant evidence of self‐selection into managed care plans. After accounting for selection, an individual enrolled in an health maintenance organization (HMO) plan has 2 more visits to a doctor and has 0.1 more visits to the emergency room per year than would the same individual enrolled in a nonmanaged care plan. Copyright © 2006 John Wiley & Sons, Ltd.
Permanent vs transitory components and economic fundamentals
Authors: Garratt Anthony , Robertson Donald , Wright Stephen 
Published: March 2006

AbstractAny non‐stationary series can be decomposed into permanent (or ‘trend’) and transitory (or ‘cycle’) components. Typically some atheoretic pre‐filtering procedure is applied to extract the permanent component. This paper argues that analysis of the fundamental underlying stationary economic processes should instead be central to this process. We present a new derivation of multivariate Beveridge–Nelson permanent and transitory components, whereby the latter can be derived explicitly as a weighting of observable stationary processes. This allows far clearer economic interpretations. Different assumptions on the fundamental stationary processes result in distinctly different results, but this reflects deep economic uncertainty. We illustrate with an example using Garrattet al.'s (2003a) small VECM model of the UK economy. Copyright © 2006 John Wiley & Sons, Ltd.
Epimerization and desaturation by carbapenem synthase (CarC). A hybrid DFT study
Authors: Borowski Tomasz , Broclawik Ewa , Schofield Christopher J. , Siegbahn Per E. M. 
Published: March 2006

AbstractThe mechanism of the unusual epimerization and desaturation reactions catalyzed by carbapenem synthase was investigated using the hybrid density functional method B3LYP. Several different models have been used in the calculations to study five component reactions. Both protonated and deprotonated models for the substrate have been explored so that the effects of hydrogen bonds could be characterized. Besides the iron site, it is proposed that a some tyrosine residue, possibly Tyr67, is involved in the hydrogen abstraction step. The calculated energetics and barrier heights support this hypothesis, and are consistent with the known experimental data concerning CarC and other 2‐oxoglutarate dependent dioxygenases. © 2006 Wiley Periodicals, Inc. J Comput Chem 27: 740–748, 2006